DEVICE FOR PERFORMING POWERED THREADING OPERATIONS AND METHOD THEREFOR
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority from US provisional application serial No.
61/374,038 filed on August 16, 201 0 and US non-provisional application serial No.
13/207,610 filed August 11, 201 1 both of which herein are incorporated by specific
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to powered devices for performing a
variety of operations upon workpieces and particularly, devices for cutting,
reaming, and threading pipe ends. The invention also relates to powered devices
for cutting, removing, and/or forming workpiece materials.
BACKGROUND OF THE INVENTION
[0003] Threads are used on a wide array of mechanical components, piping,
and conduit for engaging components together and/or to provide a sealing
connection between components. Numerous thread sizes and thread
configurations are known, such as tapered threads and non-tapered or "straight"
threads. Within each class, a variety of different thread forms have been
developed and used depending upon the application, type of workpiece, customs
of the locale, and preferences of the user.
[0004] Devices for forming threads on pipe ends are well known in the art.
Such devices use one or more dies that form a helical thread extending from one
region of the pipe to another region. The die is orbited about the axis of the pipe
and/or the pipe is rotated while the die is engaged with a select region of the pipe
to form the thread.
[0005] When assembling piping systems or when forming custom piping
layouts, sections of pipe are typically cut and threaded at a construction or
assembly site. As a result, portable or semi-portable pipe threading devices have
been developed which can be used at the job site to prepare threaded pipe ends.
Many of these devices are powered by electric motors and include one or more
accessories for performing other operations typically associated with threading,
such as cutting and reaming operations. As far as is known, these previous
threading devices were relatively inefficient in terms of power consumption and
limited in the extent of control features. As a result, relatively low productivity
levels were associated with previously known devices. Additionally, previously
known threading devices had relatively low durability as a result of the use of
components susceptible to wear, i.e. brushes.
[0006] Although most currently available threading devices are satisfactory, it
would be desirable to provide an improved device. Specifically, it would be
beneficial to provide a threading device which operated with greater efficiency
than currently known devices. It would also be desirable to provide a threading
device that would enable gains in productivity. And, it would be desirable to
provide a device that exhibits a high level of durability.
SUMMARY OF THE INVENTION
[0007] The difficulties and drawbacks associated with previously known
systems are addressed by the present devices, systems and methods for
performing one or more operations on a workpiece such as pipe or conduit.
[0008] In one aspect, the present invention provides a powered threader
device comprising a frame assembly, a selectively releasable chuck assembly
adapted for retaining and rotating a workpiece about a workpiece central axis, a
selectively positionable die assembly for forming threads in the workpiece, and a
brushless DC electric motor supported by the frame assembly. The brushless
motor provides a powered rotary output in selectable engagement with the chuck
assembly to thereby selectively rotate the workpiece.
[0009] In another aspect, the present invention provides a powered threader
device comprising a frame assembly, a brushless DC electric motor supported on
the frame assembly providing a powered rotary output, a selectively releasable
chuck assembly supported on the frame assembly and adapted for retaining and
rotating a workpiece about a workpiece central axis, a drive train for transmitting
rotary motion from the rotary output of the brushless motor to the chuck assembly,
a selectively positionable die assembly supported on the frame assembly for
forming threads in the workpiece, and control provisions for controlling rotation of
the workpiece and position of the die assembly.
[0010] In still another aspect, the present invention provides a method of
forming a thread in a workpiece. The method comprises releasably securing a
workpiece in a chuck assembly adapted for retaining and rotating the workpiece
about a workpiece central axis. The method also comprises contacting a
selectively positionable thread forming die with the workpiece. And, the method
additionally comprises rotating the workpiece by use of a brushless DC electric
motor. Upon rotation of the workpiece about the workpiece central axis, the
thread forming die is contacted with the workpiece to thereby form a thread in the
workpiece.
[001 1] In yet another aspect, the present invention provides a method for
monitoring operation of a powered threader device. The method comprises
activating the threader device such that the device is placed in electrical
communication with a source of electrical power. The method also comprises
comparing the incoming electrical current to a threshold value, whereby if the
incoming current is less than the threshold value the method is placed in a hold
state, and if the incoming current is greater than the threshold value the method
proceeds to an integrating operation. The method additionally comprises
integrating electrical current consumed by the threader device as a function of
time during at least a portion of operation of the threader device, to thereby
produce an integration value. The method further comprises comparing the
integration value to at least one benchmark or archived value stored in an
electronic memory unit of the threader device, the benchmark or archived value
selected from the group consisting of a value representative of a cutting operation,
a value representative of a reaming operation, and a value representative of a
threading operation. And, the method also comprises identifying the type of
operation performed by the threader device by determining which of the
benchmark or archived values most closely corresponds to the integration value.
[0012] In still another aspect, the present invention provides a method for
monitoring operation of a powered threader device. The method comprises
activating the threader device such that the device is placed in electrical
communication with a source of electrical power. The method additionally
comprises comparing the incoming electrical current to a first threshold value,
whereby if the incoming current is less than the first threshold value the method is
placed in a hold state, and if the incoming current is greater than the first threshold
value the method proceeds to a sensor monitoring operation. The method also
comprises monitoring at least one sensor output of the threader device, the
sensor selected from the group consisting of a cutter sensor, a reamer sensor,
and a thread or die sensor. The method additionally comprises comparing
magnitude of instantaneous electrical current consumed to a second threshold
value, whereby if the instantaneous current magnitude is greater than the second
threshold value, the method proceeds to another comparing operation. The
method also comprises comparing an output of the at least one sensor and the
instantaneous electrical current to at least one set of benchmarks or archived
values selected from the group consisting of values representative of a cutting
operation, values representative of a reaming operation, and values
representative of a threading operation. And, the method further comprises
identifying the type of operation performed by the threader device by determining
which of the benchmark or archived values most closely correspond to the output
of the at least one sensor and the instantaneous electrical current.
[0013] In another aspect, the present invention provides a method for
performing a threading operation on a workpiece using a powered threader
device. The method comprises securing the workpiece in the threader device,
obtaining parameters for the desired threading operation, determining the target
thread length, and confirming existence of appropriate conditions thereby enabling
the threading operation. The method also comprises rotating the workpiece while
secured in the threader device. The method additionally comprises contacting
and engaging a threading die or tool with the workpiece. The method also
comprises linearly displacing the threading die or tool alongside the workpiece to
thereby form a helical thread. The method further comprises monitoring the
distance of linear displacement of the threading die or tool. And, the method
comprises comparing the distance of linear displacement of the threading die or
tool to the target thread length. The method further comprises concluding the
threading operation upon the distance of linear displacement of the threading die
or tool being equal to or greater than the target thread length.
[0014] In still another aspect, the present invention provides a method for
performing a threading operation on a workpiece using a powered threader device
including a brushless DC electric motor. The method comprises securing the
workpiece in the threader device. The method also comprises obtaining
parameters for the desired threading operation. The method additionally
comprises determining the target thread revolutions. The method also comprises
confirming existence of appropriate conditions thereby enabling the threading
operation. The method then involves rotating the workpiece while secured in the
threader device by activating the brushless DC electric motor. The method
comprises contacting and engaging a threading die or tool with the workpiece.
The method comprises linearly displacing the threading die or tool alongside the
workpiece to thereby form a helical thread. The method also comprises
monitoring the angular displacement of the brushless DC electric motor. The
method additionally comprises comparing the angular displacement of the
brushless DC electric motor to the target thread revolutions. And, the method
further comprises concluding the threading operation upon the angular
displacement of the brushless DC electric motor being equal to or greater than,
the target thread revolutions.
[0015] As will be realized, the invention is capable of other and different
embodiments and its several details are capable of modifications in various
respects, all without departing from the invention. Accordingly, the drawings and
description are to be regarded as illustrative and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 is a perspective view of a preferred embodiment thread
forming device in accordance with the present invention.
[0017] Figure 2 is a detailed and partial cut-away view of the preferred
embodiment thread forming device depicted in Figure 1.
[0018] Figure 3 is another detailed view of the preferred embodiment thread
forming device depicted in Figure 1.
[0019] Figure 4 is yet another detailed view of a front region of the preferred
embodiment thread forming device shown in Figure 1.
[0020] Figure 5 is a full cross sectional side elevational view of the preferred
thread forming device of Figure 1.
[0021] Figure 6 is a partial cross section of the preferred embodiment thread
forming device depicted in Figure 1 showing a preferred drive and gear assembly.
[0022] Figure 7 is a schematic illustration of a functional configuration of the
preferred embodiment thread forming device in accordance with the present
invention.
[0023] Figure 8 is a flowchart illustrating a preferred operation sequence of the
preferred embodiment thread forming device in accordance with the invention.
[0024] Figure 9 is a flowchart illustrating another aspect of a simultaneous
preferred operation of the preferred embodiment thread forming device.
[0025] Figure 10 is a flowchart illustrating another aspect of the simultaneous
preferred operation of the preferred embodiment thread forming device.
[0026] Figure 11 is a flowchart illustrating yet another aspect of the
simultaneous preferred operation of the preferred embodiment thread forming
device.
[0027] Figure 12 is a flowchart illustrating still further another aspect of the
simultaneous preferred operation of the preferred embodiment thread forming
device.
[0028] Figure 13 is a graph of electrical current over time illustrating various
profiles of current draw for three operations using the preferred embodiment
thread forming device.
[0029] Figure 14 is a flowchart illustrating an operational aspect relating to
nominal thread data storage of the preferred embodiment thread forming device.
[0030] Figure 15 is a flowchart illustrating another operational aspect relating
to machine diagnostics of the preferred embodiment thread forming device.
[0031] Figure 16 is a graph illustrating current or torque as a function of time
and representative profiles for (i) a nominal state, and (ii) a worn component state.
[0032] Figure 17 is a flowchart illustrating menu operation pertaining to the
preferred embodiment thread forming device.
[0033] Figure 18 is a graph illustrating total efficiency of a brushless motor
compared to a universal motor over a range of torque loads.
[0034] Figure 19 is a graph illustrating power consumed by a preferred
embodiment thread forming device using a brushless motor compared to a thread
forming device using a universal motor while performing a threading operation.
[0035] Figure 20 is a graph illustrating torque outputs at various rotational
speeds of a brushless motor with a rectifier, a brushless motor with a controller
having a power factor correction function unit, and a universal motor.
[0036] Figure 2 1 is a graph of temperature increases for a vented motor with
an internal fan, and an enclosed motor with an external fan.
[0037] Figure 22 is a graph of line voltage and current over time for a
brushless motor using a rectifier.
[0038] Figure 23 is a graph of line voltage for a brushless motor using a
controller with a power factor correction function.
[0039] Figure 24 is a graph illustrating effects of torque current limiting on
RPM for a brushless motor and a universal motor.
[0040] Figure 25 is a graph illustrating typical stresses and deflections as
increasing levels of torque are applied to a threading machine component.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0041] The present invention provides various devices, systems, and methods
for performing various operations. For purposes of understanding the invention,
the invention will be described in terms of thread forming devices. However, it will
be understood that in no way is the invention limited to these particular
embodiments.
[0042] The present invention threader device provides significantly increased
levels of operating efficiency and productivity gains as compared to previous
devices. As explained in greater detail herein, by enabling control of threading,
cutting, and reaming operations using information obtained by associated
sensors, the threader device provides significant improvements in productivity.
The present invention threader device also exhibits greater durability as compared
to previous devices.
[0043] As explained herein, certain versions of the present invention threader
device include various features that enable improved operator control over the
device and its components. For example, multiple modes of operation are
provided whereby a threading operation can be performed in which one or more
parameters relating to electrical current consumption, cycle counting, and sensor
feedback are utilized to control the operation of the device. Moreover, the device
may be operated at relatively high efficiency levels due at least in part to
operational gains from the use of certain motors, and user selected controls.
Brushless Motor
[0044] In accordance with the present invention, the various devices and
systems described herein preferably utilize a brushless DC electric motor.
Preferably, the electric motor is a brushless direct current (DC) electric motor,
sometimes referred to in the art as a BLDC motor. A brushless DC (BLDC) motor
is a synchronous electric motor powered by direct current (DC) electricity using an
electronic commutation system, rather than a mechanical commutator and
brushes.
[0045] Two types of BLDC motors exist. A stepper or servo motor type may
have multiple poles on the rotor, which is generally in the form of a fixed
permanent magnet. This type is referred to herein as a permanent magnet
brushless DC electric motor. The second type of BLDC motor is a reluctance
motor. This second type may not have permanent magnets, but instead use
salient poles that are pulled into alignment by a timed drive. This type is referred
to herein as a switched reluctance brushless DC electric motor.
[0046] In a BLDC motor, the electromagnets do not move. Instead, the rotor
or permanent magnets rotate and the stator remains static. This overcomes the
challenge of how to transfer current to a moving electromagnet. In order to turn
the rotor, the brush-system/commutator assembly of a conventional motor is
replaced by an electronic controller. The controller performs a timed power
distribution similar to that found in a brushed DC motor, but uses a solid-state
circuit rather than a commutator/brush system.
[0047] BLDC motors offer several advantages over conventional brushed DC
motors, including higher efficiency and reliability, reduced noise, longer lifetime
(no brush and commutator wear), elimination of ionizing sparks from the
commutator, more power, and overall reduction of electromagnetic interference
(EMI). With no windings on the rotor, BLDC motors are subjected to less
centripetal forces, and because the windings are supported by the housing, they
can be cooled by conduction, requiring no airflow inside the motor for cooling.
This in turn means that internal components of the motor can be entirely enclosed
and protected from dirt or other foreign matter. Additionally, BLDC motors exhibit
reduced size and weight as compared to equivalent brushed motors. This
translates to higher power to weight ratios over equivalent brushed motors.
Moreover, BLDC motors are also typically slower at the same horsepower as
equivalent brushed motors. Thus, BLDC motors exhibit higher power to RPM
ratios as compared to brushed motors. Depending upon the configuration and
implementation of the BLDC motor, it may be possible to eliminate one or more
drive gears otherwise necessary to achieve certain rates of powered rotation of a
drive output.
[0048] The maximum power that can be applied to a BLDC motor is
exceptionally high, limited almost exclusively by heat. As will be appreciated, heat
can weaken the magnets. Certain magnets typically demagnetize at temperatures
greater than 100° C.
[0049] In addition, BLDC motors are often more efficient in converting
electricity into mechanical power than brushed DC motors. This improvement is
largely due to the absence of electrical and frictional losses due to brushes. The
enhanced efficiency is greatest in the no-load and low-load region of the motor's
performance curve. Under high mechanical loads, BLDC motors and high-quality
brushed motors are comparable in efficiency. Increased efficiency of BLDC
motors is also due at least in part to increases in pole count. Generally,
increasing the number of poles causes a reduced step angle, thereby resulting in
a reduced distance between magnets. Thus, in comparing a BLDC motor to a
similarly sized brushed motor, the BLDC motor operates with greater efficiency.
[0050] A particularly preferred type of stator configuration used in a BLDC
motor is one utilizing a segmented lamination technology. A motor using this
technology features significantly reduced end turns in comparison to a traditional
brushless motor, and results in increased thermal efficiency. Details as to
segmented lamination stator technology are provided in an article by R. Welch,
"Think Thermal to Increase Motor Efficiency," Motion System Design , p. 32-33,
August 2009. Stators exhibiting this configuration are referred to herein as a
"segmented tooth stator."
[0051] Although the preferred embodiments described herein utilize a
brushless motor, it will be understood that in certain versions of the invention a
conventional electric motor and one using brushes may be employed. That is, the
invention includes threader devices having the noted sensors and control
provisions used in conjunction with a brushed electric motor.
Thread Forming Devices
[0052] The present invention relates to systems, devices, and various
methods for modifying workpieces and in particular, forming threads on pipe ends,
cutting pipes, and reaming pipe ends. The systems and devices for modifying
and/or performing the various operations described herein preferably use a
brushless motor, all of which are described in greater detail herein. It will be
understood that although the present invention is described in terms of threading,
cutting, and reaming pipe ends, in no way is the invention limited to such
operations. Instead, the invention is contemplated to be applicable to performing
a wide array of operations on numerous workpieces and in various applications.
The preferred embodiment threader device described herein is merely one
example of an embodiment of the present invention.
[0053] Generally, the present invention provides a powered threader device
comprising a frame assembly, an electric motor that provides a powered rotary
output, a chuck assembly for retaining and rotating a workpiece about a workpiece
central axis, a drive train for transmitting rotary motion from the rotary output to
the chuck assembly, and a selectively positionable die assembly for forming
threads in the workpiece. The powered threader device also preferably comprises
electronic control provisions for controlling and monitoring rotation of the
workpiece and position of the die assembly while forming threads in the
workpiece.
[0054] The powered threader device of the present invention also preferably
comprises one or more components or assemblies for performing additional
operations. For example, in addition to forming one or more threads, typically it is
also necessary or desired to cut and/or ream piping. Thus, the powered threader
also comprises cutting devices and reaming devices.
[0055] Details as to the general assembly and operation of thread forming
devices are provided for example in US Patents 2,768,550; 2,91 6,749; 1,947,874.
[0056] Figure 1 is a perspective view of a preferred embodiment system 100
in accordance with the present invention. The preferred system 100 comprises a
pipe threading device 110 and a footswitch 10 in communication with the device
110 via a footswitch cord 58. The footswitch 10 at least partially controls the
operation of the device 110 and is primarily for on/off control of the device. The
device 110 includes a variety of provisions for cutting, reaming, and threading pipe
or other workpieces. The device 110 includes numerous features which are
described in greater detail herein, and employs a brushless DC motor, also
described in greater detail herein.
[0057] Figure 2 is a detailed view of the interior of the preferred embodiment
pipe threading device 110 illustrating its various components and configurations.
The device 110 comprises a longitudinally extending spindle tube 37 rotatably
supported by a rear spindle bearing 33 and a front spindle bearing 45. A rear
chuck 3 1 is preferably disposed along a rearward region of the device 110. The
rear chuck 3 1 and a forwardly disposed chuck jaw 55 serve to retain and engage
a pipe or other workpiece disposed in the spindle tube 37. The spindle tube 37
receives a pipe or other workpiece to subsequently be subjected to one or more
operations such as threading, cutting, and/or reaming.
[0058] The device 110 also comprises a motor 28 which is preferably a
brushless DC motor. The motor 28 is operably engaged with a main drive pinion
50 via a gear box 26. Upon rotation of the motor 28, powered rotation is provided
at the main drive pinion 50. Preferably positioned along the exterior of the motor
28 are one or more heatsink(s) 59. As will be appreciated, heatsink 59 promotes
cooling of the motor 28 by transfer of heat from the motor to one or more heat
radiating fins.
[0059] Referring further to Figure 2, the main drive pinion 50 is engaged with a
ring gear 53. The ring gear 53 is located near a handwheel 54 preferably
disposed immediately forwardly adjacent to the ring gear 53. The ring gear 53 is
engaged with the spindle tube 37. The chuck body 56 is engaged with the chuck
jaw 55. The handwheel 54 rotates about the spindle tube 37 and a chuck body 56
shown in Figure 5 so that the jaws can be moved radially into position using a
scroll 57 (see Figure 5). The chuck jaw 55 is adjusted to engage a pipe disposed
in the spindle tube 37. Upon tightening the chuck jaw 55 about a pipe, the pipe is
rotated about its longitudinal axis and within the spindle tube 37 by the motor 28
rotating the ring gear 53 and thus the chuck body 56, the handwheel 54 and the
chuck jaw 55.
[0060] Referring further to Figure 2, device 110 also preferably comprises a
linearly displaceable carriage 63 generally supported on one or more carriage rails
66. The carriage 63 includes mounting provisions for supporting a reamer sensor
11, a die sensor 12, and a cutter sensor 13 . Disposed generally above and coplanar
with the die sensor 12, is a die head 64. The cutter sensor 13 is co-planar
with a cutter 67 (see Figure 3). The reamer sensor 11 is co-planar with a reamer
65 when in a "down" position. The die head 64 is supported on or by the carriage
63. Upon linear movement of the carriage 63, the die head 64 is also linearly
displaced. As will be appreciated, the die head 64 is selectively positioned along
a desired region of a pipe or other workpiece during a thread forming operation.
The primary direction of movement of the die head 64 during a thread forming
operation is parallel or at least substantially so, to the axis of rotation of the
workpiece. Thus, as the workpiece is rotated, linear movement of the die head 64
alongside the workpiece, enables the formation of a helical thread.
[0061] With continued reference to Figure 2, the device 110 also comprises a
hydraulic pressure system and/or lubrication system to one or more components
of the device. For example, an oil level sensor 22 is provided in the system and is
positioned within the sump to detect the oil level therein. One or more oil intake
screens 62 are provided in communication with oil lines 6 1 . Also provided in
communication with one or more oil flow lines 6 1 are solenoid valves 6 which
selectively govern oil flow to components of the device 110 . For example, the
solenoid valves 6 govern flow of oil to a positive displacement pumping unit or
gerotor 52. One or more temperature sensors are provided to provide information
as to oil temperature.
[0062] The device 110 comprises a frame and/or base 4 1, a rear cover 32,
and associated support and enclosure members, such as one or more motor
mount brackets 60 for supporting and retaining the motor 28.
[0063] Device 110 also preferably includes control provisions, memory
provisions, numerous sensors, electronic components, and associated items such
as an encoder 25 typically located along a rearward region of the motor 28. The
encoder 25 provides information concerning rotor position and speed feedback. A
control enclosure 29 preferably houses the electronics and memory provisions
governing the operation of the device 110 and/or the motor 28. A chuck position
sensor 2 1 may be provided in association with the chuck jaw 55 to provide an
indication as to the position of the chuck jaw 55 and/or the presence of a
workpiece. Similarly, a rear chuck sensor 20 may be provided in association with
the rear chuck 3 1 to provide an indication as to the position of the rear chuck 3 1
and/or the presence of a workpiece. A carriage position sensor 19 is provided to
provide information as to the position and/or location of the carriage 63.
[0064] The device 110 may also include a selectively positionable and
adjustable reamer assembly 65, preferably located along a frontward region of the
device 110 . As will be appreciated, the reamer assembly 65 which is disposed on
the carriage 63, is urged into an open end of a pipe or conduit to remove burrs,
filings, or other debris from the interior and specifically along an inner edge of the
open end pipe face, by moving the carriage. Specifically, the carriage 63 is
manually and selectively positioned by turning a carriage handwheel 69 (Figure
3). As will be understood by reference to Figure 2, a reamer arm can be
selectively raised or lowered to align the reamer 65 with the center of a pipe when
disposed in the spindle tube 37.
[0065] Figure 3 is another perspective view of the device 110 further
illustrating various components visible or otherwise accessible along the exterior
of the device 110 . A die release 7 and an associated die release lever 68 are
provided to release engagement of a die. The die head 64 (see Figure 2) is in the
down position and remains around the pipe and can pass over the pipe once the
dies are released. The carriage wheel 69 is provided to selectively and manually
position the carriage 63, such as along one or more carriage rails 66.
[0066] The device 110 may also comprise a selectively positionable and
adjustable cutter assembly 67 for performing one or more cutting operations of a
pipe. As will be appreciated, the cutter assembly 67 is used to perform one or
more cutting operations on a pipe, conduit, or other workpiece. Typically, the cuts
are taken through a plane that extends transversely or substantially so, to the axis
of rotation of the workpiece.
[0067] Referring further to Figure 3, preferably located along an exterior
region of the device 110 is a power switch 2 for controlling forward or reverse
direction of rotation. The power switch 2 can be in the form of a key having
mechanical and/or electronic provisions for interlocking operation of the device
110. Similarly, one or more toggle switches 14 are provided, which can be
configured so as to control the operation of one or more components of the device
110.
[0068] Also provided along an exterior region of the device 110 is a keypad
and/or display monitor 5 . As will be appreciated, the keypad and display monitor
serve as an operator interface to receive one or more commands, inputs, or
operational selections. Instructions and/or data can be entered via the keys or by
a touchscreen. The display monitor serves to provide visual indication or
information display of nearly any parameter associated with the device 110, its
operation, and/or operations involving modifying pipe ends or other workpieces.
[0069] Figure 4 illustrates yet another detailed perspective view of a region of
the device 110 at which various operations are performed upon a pipe or other
workpiece. Figure 4 reveals additional details of a preferred reamer 65 (shown in
the down position) and a preferred die head 64, both supported on the selectively
positionable carriage 63. As evident in Figure 4, the reamer 65 is generally
aligned with or oriented to be parallel with the axis of rotation of a workpiece (not
shown) clamped between the chuck jaw 55.
[0070] Figure 5 is another view of the preferred embodiment device 110
revealing additional details of a drive train for transferring power from the motor 28
to the ring gear 53, and additional details of other components associated with the
device 110 . The motor 28 is preferably in the form of a brushless DC motor
having a rotor 36 and an associated stator 35 generally extending about the
centrally disposed rotor 36. A motor temperature sensor 27 is preferably provided
to provide temperature measurements to an on-board control or monitoring
system. An internal fan or cooling assembly can be included in association with
the motor 28. Optionally and preferably, an external motor fan 85 is used
provided to direct air past the various motor components and provide additional
cooling thereof. Generally, the optional supplemental fan 85 is operated or
triggered by machine startup or high temperature conditions.
[0071] Referring to Figures 5 and 6, the rotor 36 and a rotor shaft 48 are
rotatably supported by rotor stage bearings 39 and 39a. The rotor shaft 48
transmits rotational power from the motor 28 to a positive displacement pump or
gerotor 52 and a rotor pinion 47. The rotor pinion 47 and the gerotor 52 are on
the same shaft. A first stage helical gear 43 is operably engaged with the rotor
shaft 48 by the first gear 43 meshing with the rotor pinion 47. The first stage
helical gear 43 is rotatably supported by first gear stage bearings 38. The gear 43
and a second gear 5 1 are on the same shaft. The second gear 5 1 meshes with a
main drive spur gear 46. The main drive spur gear 46 transmits rotational power
to the ring gear 53 via a main drive pinion 50. The spur gear 46 and main drive
pinion 50 are on the same shaft. The spur gear 46 and the main drive pinion 50
are rotatably supported by main drive stage bearings 40 and 49. And, the main
drive pinion 50 meshes with the ring gear 53. The entire assembly of gears is
preferably enclosed by a gear case 44.
[0072] Various components are preferably positioned along a frontward region
of the device 110 . For example, the chuck position sensor 2 1, the chuck jaw 55,
the chuck body 56, and the scroll plate 57 are as shown in Figure 5 .
[0073] The preferred embodiment device 110 uses a relatively sophisticated
array of sensors, operator inputs, and determined states or conditions to provide
an extensive amount of information to the microprocessor-based control system of
the device. Table 1 set forth below is a listing of various preferred inputs that are
all or at least partially used in the operation of the preferred device 110 .
Table 1 - Information Providing Inputs
Input Ref. Nos. Value Unit Sensor(s) / Use / Output
Hardware
Job 5 N/A N/A Keypad w/ Display Stores work done on particular job. Allows multiple users to
Description or access the job history.
Number
Job Data 5 N/A N/A Keypad w/ Display Allows storage of job requirements and a list of parts that
must be produced or a list of tasks to complete. Allows users
to sort tasks and track progress.
Start/Stop 5 , 14 On/Off N/A Keypad w/ Display Used to turn motor on (w/ soft start), and stop machine
Buttons or Toggle Switch (initiates dynamic braking).
Forward 5, 14 Forward/ N/A Keypad w/ Display Changes rotation direction of the motor for left hand
/Reverse Reverse or Toggle Switch threading and other operations. Displays direction status.
Button Switches solenoid valve to change direction of oil flow.
Pipe Length 20 Longer or N/A hall effect, optical Alerts user to use rear centering chuck if the pipe is longer
Shorter than the spindle. Stops machine if excessive non-concentric
than rotation of the pipe occurs (picked up by accelerometer).
Spindle
Oil Level 22 Above or N/A oil level sensor, Alerts user to user to add or change oil
Below float
minimum
amount
Receiver/ 8 , 70, 7 1 N/A N/A Receiver/ Allows the user to track data from multiple machines using
Transmitter Transmitter wireless communications. Allows user to change the settings
Signals of the control remotely using an interface PC program.
Allows control features to automatically change according to
the location of the machine (GPS). Allows unit to be tracked
and recovered in case of theft.
USB 8 N/A N/A Flash Drive, USB Allows user to store parameters, settings, and login
Connector Cable information which can be recalled by the software.
[0074] Figure 7 schematically illustrates a preferred operational or functional
configuration for the preferred embodiment device 110 in accordance with the
present invention. The device 110 generally includes a group of features within or
associated with the control enclosure 29, another group of features generally
referred to as advanced control features, and a set of features referred to as
advanced communication features. It will be noted that none of the advanced
control and communication features are necessary for the basic operation of the
unit. The invention benefits from the efficiency and durability gains with these
provisions. Each of these is described in greater detail as follows.
[0075] An electrical socket or plug 1 as known in the art and the power switch
2 establish electrical power supply to the device 110 . Incoming electrical current
is directed to a rectifier or power factor correction device. Controlled DC power is
then supplied to various on-board electrical circuits, components, and the like.
The control circuitry governs operation of one or more solenoid valves 6, the die
release 7, and other components. Appropriate electronic control signals can be
collected, monitored, and/or used by the control circuitry such as signals from the
footswitch 10, the motor 28 and the motor temperature sensor 27, the encoder 25,
a current sensor 24 and other components such as the keypad and monitor 5,
memory provisions 4 for data storage, operator or external signals from a
communication interface 8, outputs from one or more signal processors, outputs
from toggle switches 14, and outputs from PWM driver printed circuit board
component 16. As shown, a circuit board temperature sensor 15 may be provided
in association with the printed circuit board driver 16. Outputs from the PWM
driver circuit board are three phase wires of the motor (A, B, and C). The switch
18 is connected with the footswitch 10 to indicate that there is an electrical
footswitch signal connection to the control and an additional connection to the
power side. Thus, if the control were to not respond to the footswitch, the phase
wires would be opened to stop motor rotation. All three phase lines would either
be opened or closed. The current sensor 24 senses current in all three phases.
[0076] A wide array of advanced control features generally relating to sensors
and information-providing or information-generating components are in
communication with the signal processing provisions. For example, the cutter
sensor 13, the die sensor 12, the reamer sensor 11, the carriage position sensor
19, the rear chuck sensor 20, the chuck position sensor 2 1, the oil level sensor 22,
and an accelerometer 23 all preferably provide one or more outputs to the signal
processing provisions 17. The accelerometer 23 can be utilized to assess a state
of tipping of the device or if the device is oriented at an excessive inclination.
[0077] A wide array of advanced communication sensors and components are
also preferably used to provide information to a communication interface 8 . For
example, a computer 3 or other microprocessor-based component is preferably in
bidirectional communication with the communication interface 8 . Similarly, a GPS
(global positioning system) receiver 70 and a transceiver 7 1 can be provided and
configured for bidirectional communication with the communication interface 8 .
The interface 8 preferably receives data from the data storage provisions 4 and is
in bidirectional communication with the control circuitry 9 .
[0078] Figure 8 illustrates a preferred method of operation 200 of the device
110. Upon receiving a start signal, an initialization check is made to confirm that
power is connected to the device 110 through the main switch 2 . This operation is
depicted as 204. Next, in operation 206, the machine is enabled from the keypad
controls 5 or from one or more toggle switches 14. Operation 206 is completed
upon receiving appropriate signals from keypad controls 5, toggle switches 14,
and main switch 2 . One or more oil sensor 22 signals (see Figures 2 and 7) are
monitored to assess whether sufficient oil levels exist within the hydraulic and/or
lubrication system, and preferably that the temperature of the oil is within an
acceptable range. This assessment is depicted as 208. In the event that a low oil
signal is detected such as via operation 2 10, a low oil level indicator is activated
as shown by 2 12. In the event that no adverse oil conditions are detected, the
device 110 prompts the operator to enter any user settings or other information.
This is depicted as operation 214. The method 200 preferably monitors or
requests from the operator, the direction of rotation to be imparted to the pipe or
workpiece. This is noted as operation 2 16 . For operation 2 16, the direction is set
by main switch 2 (see Figures 3 and 7). For reverse rotation, the device
components are configured appropriately such as by moving a valve to its reverse
position as shown in 2 18 . Similarly, for forward rotation, the valve is moved to its
forward position as shown in 220. Changes in valve positions direct pressurized
hydraulic fluid to other components of the device 110 and may selectively re
position those components. The main function of the pump is to circulate cutting
fluid, not to provide hydraulic fluid for power. It will be noted that the oil is pumped
through the die head.
[0079] Further operation of the device 110 is initiated with the footswitch 10 as
shown by operation 222. One or more parameters are recalled from the on-board
memory provisions 4 (Figure 7) such as indicated at operation 224. One or more
machine component signals are obtained and/or monitored, such as depicted at
operation 226. These signals are typically from the cutter sensor 13, the reamer
sensor 11, the die sensor 12, the accelerometer 23, etc. (see Figures 2 and 7). A
check is made to confirm that the device 110 is level, as noted by 228. In the
event that the device is not level, a display error is indicated at the operator
interface 5, 8 (see Figures 3 and 7), indicated by operation 230. Additionally,
dynamic braking is applied, shown at 232, to stop further rotation or other
operations, as depicted at 234. In the event that a proper level signal is detected,
a mode selection is made at 236. Mode selection is completed from user settings
stored in the system and user entered settings 214, 224. These modes are not
selected by the user at this time. At this juncture, one or more modes of operation
are used for subsequent operation or control of operation of the device 110. For
example, a mode 238 for operation of the device 110 can be selected with a goal
of optimizing overall efficiency. Alternatively, a goal of optimizing cycle time via
mode 240 can be selected. Yet another mode may pertain to utilizing a constant
speed, depicted as 242. One or more of these modes are then used in
conjunction with signals associated with electrical and temperature signals, to
arrive at a target RPM setpoint as noted at operations 244 and 246. One or more
control algorithms generally indicated via items 248 and 250 produce output
phase voltages 252 that are used to govern the rotational velocity of the motor 28.
For example, known PID control loops can be used for controlling motor speed.
[0080] During operation of the motor 28, one or more operational parameters
or sensors are preferably monitored, such as indicated by items 254, 256, 258,
260, and 262. Specifically, signal 254 conveys information as to whether the
current at the motor 28 is at a critical or other unsatisfactory state. The signal 256
conveys information as to whether temperature at one or more locations in the
device 110 is excessively high. The signal 258 conveys information as to whether
the footswitch 10 is pressed or otherwise activated to confirm the presence of an
operator at the footswitch 10 and/or the device 110 . The signal 260 conveys
information as to whether the device 110 is sufficiently enabled to continue with
further operation. Operation 260 is determined from switches 2 and 14 or keypad
5 . And, the signal 262 conveys information as to the horizontal inclination or
orientation of the device 110. In the event that one or more fault or error signals
are detected, an error message or indication is made at 264, and dynamic braking
266 is applied to the motor 28 to effect a stop 268.
[0081] In addition to the basic operation flowchart of Figure 8, in a preferred
embodiment, one or more simultaneous operations or control sequences are also
performed during device operation. These operations are generally performed in
parallel with the overall device operation. Figures 9-12, 13, 15, and 16 detail each
of these preferred simultaneous operations. As described in greater detail herein,
the threader device also provides various control provisions and monitoring
provisions for cutting and/or reaming components also provided in association
with the threader device.
[0082] Figure 9 is a flowchart illustrating a preferred method 300 for cycle
counting or monitoring utilizing electrical current consumption. The method is
initiated via start and receiving a footswitch activation signal generally designated
as 304. Preferably, this activates the threader device such that the device is
placed in electrical communication with a source of electrical power. The method
300 remains in a hold state if the incoming current is less than a threshold value,
which occurs unless the operation is started. This evaluation is noted as item
306. A numerical integration of current consumption as a function of time is
performed as indicated by 308. So long as the instantaneous current is greater
than the threshold value, the integration calculation continues. However, the
integration is stopped if the instantaneous current value is less than the threshold
value. These operations are depicted as 3 10 and 3 12 . Once a final integration
current value is obtained, that value can be output or displayed, as depicted by
314. Additional operations or analyses can be performed using the final
integration values. For example, by comparing the integration value to benchmark
or archived values stored in the system memory, the type of operation may be
determined, as indicated by 3 16 . An example of this is described later herein in
conjunction with Figure 13 . Preferably, the incoming electrical current is
compared to a threshold value. If the incoming current is less than the threshold
value, the method is placed in a hold state. If the incoming current is greater than
the threshold value, the method proceeds to an integration operation. The
integration operation involves integrating electrical current consumed by the
threader device as a function of time during at least a portion of operation of the
threader device to thereby produce an integration value. The integration value is
compared to at least one benchmark or archived value stored in electronic
memory of the threader device. The benchmark or archived value is preferably
one or more of a value representative of a cutting operation, a value
representative of a reaming operation, and a value representative of a threading
operation. The type of operation which the threader device performed or in
certain instances, is currently performing, can be determined by assessing which
of the benchmark or archived values most closely correspond to the integration
value. The integration value is preferably stored in one or more memory
provisions or otherwise archived, as shown in 3 18. Upon reaching a final
integration value and/or receiving a stop signal, the method 300 may initiate
dynamic braking 320 of the motor to effect a stop 322.
[0083] Figure 10 is a flowchart illustrating another preferred method 400 for
cycle counting or monitoring using one or more sensors. Upon starting the
sequence and receiving a signal indicating activation of the footswitch, e.g. 404,
the current consumption is monitored and compared against a threshold value, as
shown by 406. Once the current value is greater than the threshold value, a
determination is made whether the one or more particular tools are in use. Once
confirmation is made of tool use via the appropriate sensor(s), e.g. 408, the
current magnitude is assessed at 4 10. The instantaneous current draw is
compared to a threshold value, e.g. 4 12 . So long as the instantaneous current
value is greater than the threshold value, information is output as to tool use and
maximum current draw, 414. This information is compared to benchmark and/or
archived values stored in memory provisions to determine the particular type of
operation, 4 16 . Preferably, the incoming electrical current is compared to a
threshold value. If the incoming current is less than the threshold value, the
method is placed in a hold state. If the incoming current is greater than the
threshold value, the method proceeds to a comparing operation. The comparing
operation involves comparing the incoming electrical current to a first threshold
value, whereby if the incoming current is less than the first threshold value the
method is placed in a hold state. If the incoming current is greater than the
threshold value, the method proceeds to a sensor monitoring operation. In this
operation, at least one sensor output of the threader device is monitored. The
sensor can be a cutter sensor, a reamer sensor, and/or a thread or die sensor.
The magnitude of instantaneous electrical current consumed is compared to a
second threshold value. If the instantaneous current magnitude is greater than
the second threshold value, the method proceeds to another comparing operation.
Next, an output(s) of the at least one sensor and the instantaneous electrical
current consumed by the threader are compared to at least one set of
benchmarks or archived values, which may be values representative of a cutting
operation, values representative of a reaming operation, and values
representative of a threading operation. The type of operation performed by the
threader device is identified by determining which of the benchmark or archived
values most closely correspond to the output of the at least one sensor and the
instantaneous electrical current. Again, an example of this is described herein in
conjunction with Figure 13 . Cycle data and other parameters are preferably
stored in on-board memory provisions, 4 18. Upon completing the operation,
dynamic braking of the motor is initiated, 420 to effect a stop 422.
[0084] Generally, the current integration and the current magnitude are
monitored in the operations depicted in Figures 9 and 10 as long as the
instantaneous current exceeds a threshold value such as depicted in Figure 13,
which thereby indicates that some type of operation is being performed. Once the
current falls below the threshold, the integration value or maximum current is
compared to benchmarks.
[0085] Figure 11 is a flowchart of a preferred embodiment method 500 for
performing a threading operation on a pipe end using the preferred device 110 in
accordance with the present invention. Upon securing a pipe in the device and
initiating the method 500 by receipt of a start signal, the method obtains
parameters 504 for the threading operation such as thread forms to be used.
Such information is preferably stored in on-board memory provisions 4 (Figure 7).
That information may also be entered by the operator or from another source.
The method 500 is enabled or otherwise proceeds upon detection of one or more
signals from the footswitch 10, shown as operation 506. Next, upon sensing the
chuck diameter, via operation 508, the target thread length is then determined at
5 10. Checks are made to confirm that the die head is appropriately positioned,
via operation 5 12, and electrical current levels exceed a predetermined threshold
value, as in operation 514. Upon confirmation of appropriate conditions, it is
known that a threading operation is occurring. In the event that either of these
conditions 5 12 and 514 is not met, the method 500 is suspended and/or placed
into a pause mode until operator intervention occurs. In the event that conditions
5 12 and 514 are satisfied, and as the threading operation is underway,
measurement of carriage position 5 16 is made. As will be appreciated, a
threading die or tool is contacted and engaged with the pipe or workpiece as the
pipe is rotated. The threading die or tool, preferably supported on a carriage, is
linearly displaced alongside the rotating pipe to thereby form a helical thread.
During the threading operation, the carriage travel is periodically checked and
compared to the initial measurement. These actions are denoted as 5 18 and 520.
Threading continues until the carriage travel equals the previously determined
target thread length from operation 5 10. Upon reaching such state, the threading
operation is concluded and the dies are released from the pipe (released by die
release 7 shown in Figure 3), as indicated at operation 522. Relevant parameters,
data, and other information associated with the threading operation are stored in
on-board memory provisions 4 (Figure 7) on the device, indicated via operation
524. A dynamic braking procedure 526 can be initiated upon the motor to thereby
effect a stop 528.
[0086] Figure 12 illustrates another preferred embodiment method 600 for
performing a threading operation on a pipe or other workpiece using the preferred
embodiment device 110 in accordance with the invention. The preferred method
600 parallels the previously described method 500 except the method 600
monitors progress of a threading operation by analyzing angular displacement of
the motor 28 as opposed to linear displacement of the carriage 63. Operations
604, 606, 608, 612, 614, 622, 624, 626, and 628 generally correspond to
previously described operations 504, 506, 508, 5 12, 514, 522, 524, 526, and 528
noted in association with Figure 11. Specifically, the position of one or more
encoders 25 (Figures 5 and 7) on the motor shaft (or any corresponding rotary
component in engagement therewith) are monitored to determine cumulative
rotations. That total is compared to a target total number of rotations as
determined by thread parameters at 610. So long as a current total of rotations is
less than the target total necessary to complete a threading operation, thread
formation by the device continues. Once the monitored number of rotations is
equal to (or exceeds) the targeted number of rotations for threading, the method
600 proceeds to conclusion. This determination is generally indicated at
operations 6 16, 6 18, and 620.
[0087] Figure 13 is a graph illustrating current consumption characteristics for
three different operations using the device. Specifically, current draws are
depicted for cutting, reaming, and threading operations. As evident in Figure 13,
each operation can be characterized by a particular shape or profile noted on the
graph. These shapes or profiles serve as "signatures" of the respective operation.
Thus, it will be appreciated that software algorithms can be readily used to identify
a particular operation by analyzing a current draw profile. Furthermore, one or
more "ideal" current draw profiles can be stored, and against which, present
current draw profiles are then compared to provide real-time indication as to the
progress and state of an operation.
[0088] Figure 14 is a flowchart illustrating a preferred operation 700 for
storage of nominal thread data. Generally, after receiving a start or other signal
indicating operation of the device 110, a series of operator prompts or information
is requested and/or input by the operator such as parameters pertaining to the
device 110, new dies, cutters, oil, and preferred settings. These are collectively
depicted as operation(s) 704. Next, the operator may be prompted and/or enters
information as to parameters of pipe size, thread form, material, etc. These are
collectively referred to as operation 706. Next, cycle counting methods such as
previously described in conjunction with method 300 of Figure 9 or method 400 of
Figure 10 are performed, as generally referenced by 708. Next, in operation 7 10,
one or more outputs, i.e. 314 or 414 (see Figures 9 or 10) are stored in system
memory in conjunction with the corresponding settings. A stop to the operation is
shown as 7 12 . The result of method 700 is to produce the benchmarks previously
noted.
[0089] Figure 15 is a flowchart illustrating a preferred operation 800 for
providing device diagnostics. Upon receiving a start signal, a user enters
parameters such as pipe size, thread form, material, etc. These are collectively
referred to as operation 802. Next, cycle counting selection 804 and methods
such as previously described in conjunction with method 300 of Figure 9 or
method 400 of Figure 10 are performed, as generally referenced by 806. In
operations 808, 8 10, 314 or 414 (depending upon which method 300 or 400 is
used) nominal outputs from on-board memory, are compared to the output of 806
to determine a difference value. This is generally shown as 8 10 . As indicated at
8 12, if the difference is less than a threshold value, then the operation is stopped,
as denoted by 8 16 . And, in the event that the difference is greater than the
threshold, diagnostic information is displayed or otherwise communicated to the
user or other devices, as generally shown at 814. Examples of such diagnostic
information include, but are not limited to, alerting a user as to worn dies, cutters
and/or reamers. Diagnostics may also be accomplished by simply having user
alerts when certain cycle milestones are reached. For example, when method
300 or 400 counts to 2,000 cycles, user alerts may be issued.
[0090] Figure 16 graphically illustrates current or torque levels over time.
Nominal current or torque profiles are stored in device memory. During operation,
current or torque can be compared to such nominal profile(s). Figure 16 illustrates
an example of current or torque when the device utilizes a worn component. As
will be appreciated, worn components typically cause increases in current
consumption or required torque.
[0091] Figure 17 is a flowchart illustrating a preferred operation and device
enabling control scheme 900. Upon receiving a start or other initiation signal and
confirming a power connection through a main switch, collectively referred to as
904, a user is prompted for a password. A counter is also initialized at 906. At
operation 908, the user enters his or her password. A check of the entered
password is then made at 910. If the entered password does not match the
correct password, an error is displayed at 9 12, and a cycle counter is
incrementally increased and compared to a number representing the maximum
number of attempts allowed before the device is locked or otherwise disabled.
Although a maximum number of 3 tries is shown in method 900 via items 914 and
9 16, it will be appreciated that nearly any number of tries may be selected. In the
event that a maximum number of unsuccessful password attempts occurs, the
device is locked out at 918 and one or more stop signals 920 are issued.
[0092] In the event that a correct or authorized password is entered by the
user, a selection menu is provided to the user at 922. One possible selection from
such menu is to turn the device off, shown as 924. In that case, a stop or other
shut down sequence is initiated as generally depicted by 928. In the event a
normal or typical operation is selected by the user, wherein a method 200
depicted in Figure 8 is performed for example, after completion of such operation,
a stop 928 is issued by 926. In the event that the user selects job data at 930, the
user can view or enter various data such as pipe diameter, wall thickness, pipe
material, dies, oil, etc. These are generally referenced by 932 and 934. The
particular job data is preferably stored in non-volatile system memory 4 (see
Figure 7), in operation 936. In the event that the user selects jobsite data at 938,
the user can view or enter at operation 940 various data such as name, location,
construction information, etc., collectively shown at 942 pertaining to the jobsite.
This information is preferably stored in non-volatile system memory 4 (see Figure
7), in operation 936. In the event that history or diagnostics are selected, such as
via 944, the user selects various parameters at 946 and those parameters are
then displayed at 948. Viewing is permitted and selective viewing between any of
job data, jobsite data, and history/diagnostic information. Upon selection of a
parameter, the user may continue to select other or additional parameters via 946
or exit the method 900 as shown in decision 950. Then, the method 900 is
returned to the selection menu of 922 and the previously viewed or entered data is
stored in system memory as per 936.
[0093] It will be appreciated that in no way is the present invention limited to
any of the previously described methods, operations, sequences, or control
configurations. Instead, the invention includes a wide array of variant and
alternative methods, operations and the like. For example, although the present
invention has been described in terms of powered devices for performing cutting,
reaming, and threading operations, it will be understood that the invention is also
directed to powered devices for performing roll grooving, cut grooving, beveling,
pipe and conduit bending, and other operations. Generally, the present invention
is contemplated to be useful in a wide array of operations typically performed
upon workpieces such as cutting, reaming, and threading workpiece ends. In
addition, the invention is expected to be useful in other workpiece operations such
as roll grooving, cut grooving, and beveling. For example, the present invention
can be implemented in a variety of devices to perform various cutting operations
such as cutting with a feed screw cutter as described herein in conjunction with
the preferred embodiment devices. The invention can also be used in
embodiments that perform cutting with a single point saran cutter or other cutter
adapted for cutting plastic or plastic lined pipe. The invention can also be used in
embodiments that perform cutting with a circular pipe saw. In these cutting
applications a powered rotary drive rotates the pipe or workpiece only. The
powered rotary drive is not the source of cutting power. As noted, the present
invention can be implemented in devices that perform a wide array of threading
operations. For example, the invention can be implemented in a threading device
with a universal die head, as in the preferred embodiment device described
herein. The invention can also be used in threading applications using a
ratcheting die head using fixed chasers such as exemplified by models 11R and
12R available from Ridge Tool under the designation RIDGID® manual ratchet
threaders. The invention can also be used with threaders having receding die
heads as exemplified by models 65R, 141 , and 16 1 available from Ridge Tool
under the designation RIDGID® manual receding threaders, including related
accessories such as a drive shaft to connect a threading machine to a geared
threader for threading workpieces with diameters exceeding the capacity of the
machine. These accessories are exemplified by such components available from
Ridge Tool under the designation RIDGID® geared threader accessories. As
noted, the invention can also be used in grooving applications such as grooving
with a dedicated threading machine roll groover as exemplified by models 9 16,
9 18, and 920 available from Ridge Tool under the designation RIDGID® roll
groovers. In addition, the invention can also be used in grooving using a
combination groover which can be used for installed or immobile pipe, such as
exemplified by model 975 available from Ridge Tool under the designation
RIDGID® combo roll groover. And, the invention can be used in grooving
operations such as exemplified by a threading machine using a cut groover such
as a model 725 available from Ridge Tool under the designation RIDGID® cut
groove die head. Furthermore, as noted, the invention can also be used in
beveling operations such as by using beveling dies as similarly described for the
previously noted 725 die head. The invention can also be used in beveling
operations in conjunction with a grinder or other tool with an abrasive wheel or
belt. For many of these contemplated applications, the threading machine is used
only as a means of rotating the pipe.
[0094] The present invention provides various systems, devices, and related
methods for performing powered threading operations. Several particularly
preferred systems and devices include features related to one or more of the
following: improved energy efficiency, improved productivity, improved durability,
reduced noise during operation, improvements in controlled braking, reduced in
rush current spikes of the systems and/or devices, improvements in overload
protection, the use of various low power and low voltage controls, increased range
of input voltage, reductions in weight, improvements in assessing chaser wear,
improvements relating to assessing oil characteristics, improvements in controlling
thread length and/or size, improvements relating to assessing machine wear, and
improvements in interfacing with other systems and/or devices.
[0095] In certain embodiments, it may be preferred to provide systems and/or
devices having particular combinations of these features. Thus, three additional
preferred embodiment threading systems and/or devices are described, each with
particular features and combinations of features. Although these three preferred
embodiments are described, it will be appreciated that in no way is the invention
limited to any of these embodiments. Instead, the invention includes a wide
assortment of other embodiments having one or more features and/or different
combinations of features.
Preferred Version
[0096] A preferred embodiment threader device includes one or more of the
following features.
A. Energy Efficiency
[0097] As far as is known, previous threading devices were relatively
inefficient in terms of power consumption. The present invention threader device
provides significantly increased levels of operating efficiency and productivity
gains as compared to previous devices. Moreover, the preferred embodiment
system and/or device may be operated at relatively high efficiency levels due at
least in part to operational gains from the use of certain motors, and user selected
controls. BLDC motors offer several advantages over conventional brushed DC
motors, including higher efficiency. In addition, BLDC motors are often more
efficient in converting electricity into mechanical power than brushed DC motors.
This improvement is largely due to the absence of electrical and frictional losses
due to brushes. The enhanced efficiency is greatest in the no-load and low-load
region of the motor's performance curve. Under high mechanical loads, BLDC
motors and high-quality brushed motors are comparable in efficiency. Increased
efficiency of BLDC motors is also due at least in part to increases in pole count.
Generally, increasing the number of poles causes a reduced step angle, thereby
resulting in a reduced distance between magnets. Thus, in comparing a BLDC
motor to a similarly sized brushed motor, the BLDC motor operates with greater
efficiency.
[0098] A particularly preferred type of stator configuration used in a BLDC
motor is one utilizing a segmented lamination technology. A motor using this
technology features significantly reduced end turns in comparison to a traditional
brushless motor, and results in increased thermal efficiency. Details as to
segmented lamination stator technology are provided in an article by R. Welch,
"Think Thermal to Increase Motor Efficiency," Motion System Design , p. 32-33,
August 2009. Stators exhibiting this configuration are referred to herein as a
"segmented tooth stator."
[0099] In certain embodiments of the present invention, the use of a BLDC
motor enables reduction in the total number of gear stages in the device. Each
gear mesh imparts friction in the drive or power train, thereby detrimentally
impacting efficiency of the device. By reducing the total number of gear stages in
the device, efficiency gains are attained.
B. Productivity
[00100] Previously known threading devices were limited in the extent of
control features provided for such devices. As a result, relatively low productivity
levels were associated with previously known devices.
[00101] As explained herein, by providing specific control of threading, cutting,
and reaming operations using information obtained by associated sensors, the
preferred embodiment threader device provides improvements in productivity.
[00102] As explained herein, a preferred embodiment threader device includes
various features that enable improved operator control over the device and its
components. For example, multiple modes of operation are provided whereby a
threading operation can be performed in which one or more parameters relating to
electrical current consumption, cycle counting, and sensor feedback are utilized to
control the operation of the device.
[00103] For example, referring to Figure 8, a mode 238 for operation of the
device 110 can be selected with a goal of optimizing overall efficiency.
Alternatively, a goal of optimizing cycle time via mode 240 can be selected. Yet
another mode may pertain to utilizing a constant speed, depicted as 242. One or
more of these modes are then used in conjunction with signals associated with
electrical and temperature signals, to arrive at a target RPM set point as noted at
operations 244 and 246
[00104] Furthermore, as described herein, the preferred embodiment threader
device comprises a BLDC motor. BLDC motors offer several advantages over
conventional brushed DC motors, including for example greater levels of power.
The maximum power that can be applied to a BLDC motor is exceptionally high,
limited almost exclusively by heat.
[00105] Based on several factors, the productivity gains associated with BLDC
motors in the preferred version under discussion are not primarily related to
sensors and controls as for other preferred embodiments described herein.
[00106] For certain motor configurations, the most efficient mode of operation is
to operate the BLDC motor at the maximum power.
[00107] The preferred embodiment system and/or device comprises a control
system governing operation of the BLDC motor. In one particularly preferred
aspect, the control system includes a power factor correction (PFC) function or
unit. The power factor correction (PFC) function of the control system actively
boosts the voltage to the PWM driver PCB. As torque increases, the voltage to
the motor is maintained at a higher level compared to a rectifier configuration.
The greater voltage results in a greater motor RPM. Thus, the cycle time for an
equivalent operation is reduced.
C. Durability
[00108] As will be appreciated, it would be desirable to provide a thread
forming device that exhibits a high level of durability. The preferred embodiment
system and/or threader device also exhibits greater durability as compared to
previous devices.
[00109] The improved durability is believed to result from one or more of the
following features: With no windings on the rotor, BLDC motors are subjected to
less centripetal force. Improved durability also results from avoiding the use of
brushes in the motor.
[001 10] Additionally, previously known threading devices exhibited relatively
low durability as a result of the use of components susceptible to wear, for
example brushes in the motor.
[001 11] BLDC motors offer several advantages over conventional brushed DC
motors, including higher efficiency and reliability, and longer lifetime as a result of
no brush and commutator wear.
[001 12] Improved durability may also result from a reduced operating speed
(RPM) and/or gear stages as a result of utilizing a BLDC motor.
[001 13] Moreover, BLDC motors also typically operate slower at the same
horsepower as equivalent brushed motors. Thus, BLDC motors exhibit higher
power to RPM ratios as compared to brushed motors. Depending upon the
configuration and implementation of the BLDC motor, it may be possible to
eliminate one or more drive gears otherwise necessary to achieve certain rates of
powered rotation of a drive output.
[001 14] Improved durability also results from enclosing the motor. Specifically,
yet another advantage associated with the preferred embodiment system and/or
device relates to durability improvements as a result of eliminating entry of
external agents into the motor environment. For example, because the windings
in a BLDC motor are supported by the housing, they can be cooled by conduction,
thereby not requiring airflow inside the motor for cooling. This in turn means that
internal components of the motor can be entirely enclosed and protected from dirt
or other foreign matter. This is particularly a concern for threading machines
because metal chips are produced from the operation of the device.
[001 15] However, it will be understood that an internal fan or cooling assembly
can be included in association with the BLDC motor when utilized in the preferred
embodiment thread forming devices. Optionally and preferably, an external motor
fan such as fan 85 in Figure 5 for example can be used provided to direct air past
the various motor components and provide additional cooling thereof.
[001 16] Improved durability also results from no carbon dust generated by
brushes, as the motor is a brushless motor. Carbon particles are dispersed
through the machine and can contaminate other regions and surfaces of the
threader device.
[001 17] Improved durability also results from significant reduction in ozone
generation. BLDC motors offer several advantages over conventional brushed
DC motors, including elimination of ionizing sparks from the commutator.
[001 18] Improved durability also results from reductions in electrical noise.
BLDC motors offer several advantages over conventional brushed DC motors,
including reduction of electromagnetic interference (EMI). Reductions in electrical
noise may also result from directing incoming electrical current to a rectifier and
power factor correction device.
D. Noise Reduction
[001 19] BLDC motors offer several advantages over conventional brushed DC
motors, including reduced acoustic noise. As will be appreciated, exposure for
prolonged time periods to high levels of acoustic noise can be detrimental. BLDC
motors typically exhibit lower sound levels during operation over comparable
brushed motors.
E. Controlled Brake
[00120] Additionally, the preferred embodiment system and/or device also
includes provisions for controlled braking. For example, referring to Figure 8,
dynamic braking is applied, shown at 232, to stop further rotation or other
operations, as depicted at 234. In the event that one or more fault or error signals
are detected, an error message or indication is made at 264, and dynamic braking
266 is applied to the motor 28 to effect a stop 268.
F. Soft Start
[00121] The preferred embodiment threading system and/or device also
includes a soft start provision. The soft start provision provides a gradually
increasing electrical power source to the BLDC motor using the drive pulse width
modulation (PWM) capability. Preferably, the soft start is used to activate the
motor. In addition, the PWM capability may also be used to stop the preferred
system and/or device. Most preferably, the PWM capability initiates dynamic
braking.
G. Overload Protection
[00122] The preferred embodiment system and/or device also comprises an
overload protection feature. The overload protection can provide electrical current
overload protection and thermal overload protection. Representative examples of
these are as follows.
1. Current Overload Protection
[00123] A preferred current overload provision is shown in Figure 8 .
Specifically, signal 254 conveys information as to whether the current at the motor
28 (see Figure 2) is at a critical or other unsatisfactory state. Current overload
may be desirable as such provisions can be utilized to diagnose high torque
conditions, motor failures based on baseline data or nominal data of the motor,
and other states.
2 . Thermal Overload Protection
[00124] A preferred thermal overload provision is depicted in Figure 8 as 256
by use of a motor temperature sensor 27 (see Figure 7). The motor temperature
sensor 27 is preferably provided for temperature measurements to an on-board
control or monitoring system. An internal fan or cooling assembly can be included
in association with the motor 28. Optionally and preferably, an external motor fan
such as fan 85 in Figure 5 for example, can be used to direct air past the various
motor components and provide additional cooling thereof. Generally, the optional
supplemental fan 85 is operated or triggered by machine startup or high
temperature conditions. The signal 256 in Figure 8 conveys information as to
whether temperature at one or more locations in the device 110 is excessively
high. As shown, a circuit board temperature sensor 15 in Figure 7 may be
provided in association with the printed circuit board driver 16.
H. Universal Power Supply
[00125] The preferred embodiment system and/or device also includes
provisions to accommodate electrical power from any common source worldwide.
Typically, power sources exhibit a voltage range of from about 100 volts to about
240V, at a frequency of from about 25 Hz to about 60 Hz. Incoming electrical
power is used by a power supply (rectifier) for power factor correction. In certain
versions, it may be desired to record the incoming voltage or other power source
characteristics in non-volatile memory preferably located on-board the preferred
embodiment threader device.
I . Reduced Weight
[00126] Another feature of the preferred embodiment threading system and/or
device is the relatively low weight of the apparatus. This is partially due to the fact
that BLDC motors exhibit reduced size and weight as compared to equivalent
brushed motors. This translates to higher power to weight ratios over equivalent
brushed motors.
Additional Preferred Version
[00127] Another preferred embodiment threader device includes one or more of
the following features. Although certain features may be similar to features of the
previously described preferred version, typically the features of this preferred
version are provided for or performed using different components and/or
techniques.
A. Energy Efficiency
[00128] As noted, BLDC motors are available from various commercial
suppliers. Using a 10 pole brushless motor prototype with segmented lamination
or "segmented tooth stator," an evaluation regarding energy efficiency of BLDC
motors was undertaken. Data was collected using the motor installed in a 300
Compact pipe and bolt threading machine available from Ridge Tool under the
designation RIDGID®, with a three phase SP2201 servo motor drive available
from Control Techniques. This included dynamometer data to determine energy
efficiency versus torque, and threading data to measure energy savings based on
a threading cycle.
[00129] In one test, the dynamometer data demonstrated that an increase of
approximately 25% in peak efficiency results from using the prototype BLDC
motor. Although a three phase control was used for preliminary testing, a single
phase control is preferred for the commercial version of the unit. It is estimated
that a 5% reduction in peak efficiency would result from the change. Thus, the
data collected indicates that a gain of approximately 20% in peak efficiency would
result. See Figure 18 in this regard. The BLDC motor exhibited significantly
greater efficiencies as compared to the corresponding universal motor at all
torque values.
[00130] The threading data demonstrated that the energy savings of the
threading operation was greater than the difference in peak efficiency. This is best
illustrated by considering the area under the curve for cutting, reaming, and
threading operations. In one test, it was found that the reduction in energy used
per cycle was 43.2%. Again, this value was approximate given that a three phase
control was used. See Figure 19 . Significantly less power was required by the
BLDC motor as compared to the universal motor.
[00131] Because a threading machine is a variable load application, it is not
possible to design the motor and transmission for a single constant load or torque.
As a result, the machine can not operate at the peak efficiency all of the time. For
operation below the peak efficiency, BLDC technology is particularly suited to
provide energy savings.
B. Productivity
[00132] Using data from initial evaluations, a single phase prototype control
was developed. The performance of the motor was tested outside of a machine
using a rectifier and power factor correction (PFC) DC bus (the distinction
between each is described below). Based on the data, an increase of
approximately 20% gain in peak machine efficiency is expected. Increased
efficiency can be understood by reference to Figure 20.
[00133] Specifically, one test showed that the PFC driven BLDC motor
outperformed the universal motor and rectifier driven BLDC motor with regards to
productivity. As previously mentioned, the power factor correction (PFC) function
of the control system actively boosts the voltage to the motor to allow the speed to
be maintained as torque is increased. Data from the single phase prototype
shown in Figure 20 illustrates the difference.
[00134] All of the previously described advantages associated with improved
productivity are exhibited by the preferred embodiment under discussion.
C. Durability
[00135] As previously noted, improved durability will result from reduced RPM
and lower gear stages.
[00136] For the preferred embodiment threading machine under discussion, the
free rotational speed of the 10 pole motor was reduced by a factor of 3.75 as
compared to a universal motor it was replacing. This is approximately equal to the
gear ratio of the first intermediate stage of a conventional 300 Compact threader
device. Therefore, when utilizing certain BLDC motors in a preferred embodiment
threader device, it is possible and in certain applications likely, that one or more
gears or stages otherwise required, could be eliminated. Elimination of such
component(s) promotes durability of the resulting device and may provide
additional advantages such as reduced weight, lower cost, and improved
operating efficiency.
[00137] Improved durability may also result from enclosing the motor from
debris. This was confirmed with a heat rise test with an external heat sink and fan
configuration. This configuration produced excellent results and is preferred for
use in the preferred embodiment. Referring to Figure 2 1, an enclosed motor with
a heat sink and an external fan exhibited less temperature increase during
operation as compared to a vented motor with an internal fan.
[00138] Improved durability may also result from reduced carbon dust. Carbon
dust from the brushes of a universal motor is a contributor to the break down of an
insulation system within a motor (dielectric strength). As a result, the accumulation
of carbon dust can detrimentally reduce the life of an electrical motor.
D. Noise Reduction
[00139] Using prototype machines, the noise levels of a thread forming device
with a universal and BLDC motor were compared. In one test, the noise levels
were reduced from an average of 85 dBA to 70 dBA. This demonstrates a
significant reduction in acoustic noise by the preferred embodiment threader using
a BLDC motor.
E. Controlled Brake
[00140] During the testing of a preferred embodiment thread forming device
using a 10 pole BLDC motor, it was observed that the time required to stop the
device was greatly reduced simply by the cogging torque of the motor. The
permanent rotor magnets' interaction with the inactive stator produced enough
resistance to bring the device to a near immediate stop. Universal and induction
motors do not have this characteristic because they do not use permanent
magnets.
[00141] In the preferred embodiment thread forming system and/or device, it is
believed that no significant further reduction in stopping time can be made by
dynamic braking. However, it is contemplated that the components of the
preferred embodiment device and their inertia and that of the machine undergoing
shut down could be utilized to produce electrical power, i.e., utilize the motor as
an electrical generator.
F. Soft Start
[00142] The soft start feature described herein allows the preferred
embodiment threader device to accelerate to free speed without causing an inrush
current spike. In addition to reducing the peak load of the motor windings, the soft
start feature reduces the voltage drop that results from the current spike. The
current spike of a universal or induction motor may cause a voltage fluctuation
which disrupts the local power supply. Thus, this is yet another advantage in
utilizing a BLDC motor.
[00143] A soft start feature may be added to a universal motor using pulse
width modulation (PWM). However, as described herein, during normal use BLDC
motors operate using PWM. Thus, applying a soft start feature to the preferred
embodiment threader device is only a matter of software design and does not
require additional hardware capability.
G. Overload Protection
[00144] Referring to Figures 7 and 8, various functions relating to overload
protection are provided by the driver printed circuit board (PCB).
H. Low Voltage Controls
[00145] The preferred embodiment system and/or device also preferably
includes one or more low voltage controls. For example, referring to Figure 7, a
switch 18 is used in association with a footswitch 10 . The switch 18 is connected
with the footswitch 10 to indicate that there is an electrical footswitch signal
connection to the control and an additional connection to the power side. Thus, if
the control were to not respond to the footswitch, the phase wires would be
opened to stop motor rotation. All three phase lines would either be opened or
closed.
[00146] In the embodiment under discussion, the BLDC motor is controlled with
the PWM from the motor drive printed circuit board (PCB). In the system
configuration of a BLDC threading machine, there is no need for the controls to
carry the electrical loads of the motor itself. Instead, the controls carry, for
example, 0-5 VDC to communicate with digital inputs and outputs on the control
circuitry. This results in switches and controls with smaller and lighter
construction.
[00147] Figure 7 shows an electrical and signal connection for the footswitch.
The electrical connection is redundant and can be eliminated in this additional
preferred configuration.
I . Universal Power Supply
[00148] Any common frequency can be used for powering the preferred
embodiment threading devices because the power factor correction (PFC) device
converts the line input to a DC bus. The PFC can maintain the bus voltage (400V)
down to 90VAC line. A bus voltage of approximately 400V is commonly used to
maintain high efficiencies.
[00149] The preferred line voltage range for the preferred embodiment unit is
from about 90 to about 240 VAC, 1 Phase, 50-60 Hz based on the operation of
the PFC and the power sources available in the market. Because the BLDC driver
requires only a DC bus, various sources of different phases, frequencies, and
voltages can be used.
[00150] A wide range of applications for BLDC motors exist which use DC
sources such as batteries instead of converted AC line sources. Generally, these
configurations use motors with a lower voltage rating, for example 48V. In such
configurations, the rectifier or PFC is not needed. Instead the source is connected
directly to the driver PCB. A preferred embodiment threading machine could be
configured to operate using a DC power source with a motor designed for the DC
voltage. The benefits of the BLDC technology compared to brushed motors
(efficiency, durability, and productivity) would still be exhibited. Induction motors
can not be used with a DC source unless drive electronics are used to produce
AC waveforms.
J. Reduced Weight
[00151] Based on the previously noted 10 pole motor, the size and weight of
BLDC motors were compared to certain induction and universal motors for
threading applications. The comparison of these measurements is set forth below
as Table 2.
Table 2 - Comparison of Motor Weights
K. Limited Torque Design
[00152] In a BLDC motor, the phase current to the motor, typically expressed in
Amps-rms, is directly proportional to the torque output (in-lb). As a result, the
maximum torque of the motor can be set by limiting the current in the control
software. In this system, current feedback is provided to the control through a
current sensor. If the preferred embodiment thread forming device is provided
with current overload protection, this hardware is already in place. To implement
this feature in a device with a brushed motor, a control with current sensing
capability would need to be added to the system. This would increase the cost
and complexity of the resulting system.
[00153] A projection of the operation of a machine with a current limited motor
is presented in Figure 24. In comparison to a universal motor as is used in a
conventional 300 Compact device, the stall torque is greatly reduced. However,
the torque capability is well above the requirements of the operations typically
associated with the machine such as for example threading, reaming, cutting, and
grooving.
[00154] The design of a threading machine must take into account the worst
case for the loading of the components. Thus, the stall condition and not the
loads of the threading operation must be considered. Finite Element Analysis
(FEA) is an example of a technique used to design machine components to
withstand the maximum loads placed upon them. Figure 25 shows a
representative relationship between the torque load on the system and the
mechanical stress and deflection in a machine component. By limiting the torque,
the size and weight of machine components may be reduced according to the
lower levels of mechanical stress and deflection that result.
L. Electrical Noise
[00155] By removing the brush sparking from the system, the electromagnetic
interference (EMI) produced by the motor may be reduced. However, the effects
of the change depend on the operation of the rectifier or power factor correction
(PFC) device.
[00156] It should be noted that a rectifier and PFC are two distinctly different
ways to produce a DC source for the control and driver. A system with a PFC is
preferred for use in the preferred embodiment threader device.
[00157] A rectifier does not produce significant EMI. However, a rectifier
produces poor harmonics on the line input. This is illustrated in Figure 22. In
addition, the motor is typically unable to maintain speed at low voltages and high
torques due to voltage drops in the rectifier.
[00158] A PFC provision will correct the harmonics of the system and boost the
voltage as illustrated in Figure 23, but such provisions also produce EMI. As with
a brushed motor, filtering is required. Thus, there are no appreciable gains in EMI
for a unit with PFC although a unit with a PFC is the preferred configuration.
Additional Preferred Version
[00159] The present invention also provides additional preferred embodiment
threading systems and devices which include additional functional features such
as provisions for detecting and assessing chaser wear, oil characteristics,
occurrence of cavitation, thread length and size, machine wear, and various
interfaces.
A. Chaser Wear
[00160] Monitoring and/or analyzing electrical current draw can be used to
determine the operation in progress, e.g., thread, cut, or ream. In this feature,
volatile memory is used to track current over a time period and recognize the
"signature" of the operation. The result, i.e., type of operation, is recorded in no n
volatile memory. The operation may also be determined based on additional
information from the cutter, reamer, and die head sensors, but it is not required.
These provisions can be used to record baseline thread current information once
a user has all settings in place. These provisions can also be utilized to diagnose
high torque conditions (chaser wear) or motor failures based on baseline data or
nominal data of the motor.
[00161] Previously described Figure 14 is a flowchart illustrating an example of
storing nominal thread data.
[00162] Previously described Figure 15 is a flowchart illustrating an example of
providing device diagnostics.
[00163] Previously described Figure 16 graphically illustrates monitoring
current or torque levels over time. Nominal current or torque profiles are stored in
device memory.
B. Oil Sensors
1. Low Oil Shut-Off (Oil Control)
[00164] One or more oil sensors such as oil sensor 22 depicted in Figure 7,
provide signals which are monitored to assess whether sufficient oil levels exist
within the hydraulic and/or lubrication system. In the event that a low oil signal is
detected such as via operation 210 in Figure 8, a low oil level indicator is activated
as shown by 2 12 in that figure.
[00165] Depending upon the condition or state of an oil level sensor, alerts can
be issued to add or change oil. The device 110 also comprises a hydraulic
pressure system and/or lubrication system to one or more components of the
device. For example, an oil level sensor 22 is provided in the system and is
positioned within the sump to detect the oil level therein.
2 . Oil Temperature
[00166] For example, referring to Figure 2, the device 110 also comprises a
hydraulic pressure system and/or lubrication system to provide such to one or
more components of the device. One or more temperature sensors are provided
to provide information as to oil temperature.
3 . Cavitation/Direction
[00167] For reverse rotation of the preferred embodiment threader, the device
components are configured appropriately such as by moving one or more valves
to their reverse position such as shown in 2 18 in Figure 8 . Similarly, for forward
rotation, the one or more valves are moved to their forward position as shown in
220 in Figure 8. Changes in valve positions direct pressurized hydraulic fluid to
other components of the device and may selectively re-position those
components. The main function of the pump is to circulate cutting fluid, not to
provide hydraulic fluid for power. It will be noted that the oil is pumped through
the die head.
[00168] The preferred embodiment device also comprises a hydraulic pressure
system and/or lubrication system to one or more components of the device. Also
provided in communication with one or more oil flow lines are solenoid valves
such as valves 6 in Figure 7 which selectively govern oil flow to components of the
device. For example, the solenoid valves 6 govern flow of oil to a positive
displacement pumping unit or gerotor 52 as depicted in Figure 5 .
[00169] The control circuitry governs operation of one or more solenoid valves,
the die release, and other components.
4 . Oil Life
[00170] There is no single sensor which can be used to detect the overall
condition of the oil, in terms of its remaining useful life.
[00171] However, the inputs and hardware to determine the status of the oil are
already in place in the preferred embodiment thread forming systems and devices.
Based on oil temperature, cycle counts, current consumption, and/or the change
in oil level over time, it is contemplated that an algorithm can be used to determine
the state of the oil in the sump.
C. Thread Length and Size
[00172] Carriage position can be monitored by tracking movement of the
carriage relative to the rail. Carriage position can then be utilized to determine the
thread length and identify the type of thread based on feed, such as for example
BSPT, NPT, UNC, etc. Carriage position can also be used to trigger a die release
mechanism to ensure the proper thread length is cut. A die release and an
associated die release lever are provided to release engagement of a die.
[00173] Motor speed can be determined by calculating spindle speed from
known gear ratios used for thread length determination.
[00174] Previously described Figure 11 is a flowchart of a preferred
embodiment method 500 for performing a threading operation on a pipe end using
the preferred device 110 in accordance with the present invention, in which
carriage position is monitored.
[00175] Previously described Figure 12 illustrates another preferred
embodiment method 600 for performing a threading operation on a pipe or other
workpiece using the preferred embodiment device 110 in accordance with the
invention, in which motor revolutions and thread length are monitored.
D. Machine Wear (Cycle Counting Software Logic)
[00176] In this feature, multiple modes of operation are provided whereby a
threading operation can be performed in which one or more parameters relating to
cycle counting are monitored.
[00177] Electrical current can be used to alert a user of preventative
maintenance milestones, e.g. 1000 thread cycles.
[00178] Previously described Figure 9 is a flowchart illustrating a preferred
method 300 for cycle counting utilizing electrical current consumption.
[00179] Previously described Figure 10 is a flowchart illustrating another
preferred method 400 for cycle counting using one or more sensors.
[00180] Previously described Figure 13 is a graph illustrating current
consumption characteristics for three different operations using the device.
Specifically, current draws are depicted for cutting, reaming, and threading
operations. As evident in Figure 13, each operation can be characterized by a
particular shape or profile noted on the graph. These shapes or profiles serve as
"signatures" of the respective operation. Thus, it will be appreciated that software
algorithms can be readily used to identify a particular operation by analyzing a
current draw profile. Furthermore, one or more "ideal" current draw profiles can
be stored, and against which, present current draw profiles are then compared to
provide real-time indication as to the progress and state of an operation.
E. Interface
[00181] A preferred embodiment thread forming system and/or device
comprises one or more interface components such as a keypad and a display
monitor. As will be appreciated, the keypad and display monitor serve as an
operator interface to receive one or more commands, inputs, or operational
selections. Instructions and/or data can be entered via the keys or by a
touchscreen. The display monitor serves to provide visual indication or
information display of nearly any parameter associated with the device, its
operation, and/or operations involving modifying pipe ends or other workpieces.
[00182] An alternate interface was developed for various prototypes and it is
generally preferred over a keypad in several of the embodiments. The alternate
interface includes push buttons and switches rather than a keypad as previously
described. However, either configuration could be used.
[00183] The interface is located where the "Forward/Off/Reverse" switch 2 was
described and shown in Figure 3 . The "Forward/Off/Reverse" switch is preferably
integrated into the interface assembly.
Miscellaneous
[00184] It will be understood that the present invention devices, systems, and
methods, are applicable to a very broad and diverse range of applications. For
example, the invention is also expected to find use or application in powering a
hydraulic or pneumatic power pack which may be used for any number of
hydraulic or pneumatic tools and equipment. In addition, the present invention is
also expected to find use in powering units for compression and/or crimping
fittings or other mechanical components or hardware. Moreover, the invention is
also expected to find use in pipe taping or internal threading applications.
[00185] The present invention also includes the various devices further
comprising communication provisions for algorithms and/or providing instructional
information to the device. Numerous interlocks can be provided to enable
software downloads to the device for updating operational algorithms and/or
providing data, instructions, or system documentation. For example, instructional
text, photographs, and/or videos with supporting audio explanations could be
provided by the device. Speaker and/or headphone jacks can be provided at the
device to transmit audible information. Manuals could be stored in electronic
format on the device in multiple languages. Such information could be displayed
on one or more display outputs on the device. Provisions may be implemented to
alert a supervisor or other individual if a fault state has been detected.
[00186] Additional sensors can be included in the device and on related
components such as the footswitch or other user operated controls. It is also
contemplated that motion sensors or other operator sensing systems could be
used in conjunction with the various devices of the invention. Assessments of the
input power can be made to prevent faulty operation of the device or to modify the
operation of the device to suit the power source. Keycards or other identifying
means could be used.
[00187] Many other benefits will no doubt become apparent from future
application and development of this technology.
[00188] All patents, published applications, and articles noted herein are
hereby incorporated by reference in their entirety.
[00189] It will be understood that any one or more feature or component of one
embodiment described herein can be combined with one or more other features or
components of another embodiment. Thus, the present invention includes any
and all combinations of components or features of the embodiments described
herein.
[00190] As described hereinabove, the present invention solves many
problems associated with previous type devices. However, it will be appreciated
that various changes in the details, materials and arrangements of components,
which have been herein described and illustrated in order to explain the nature of
the invention, may be made by those skilled in the art without departing from the
principle and scope of the invention, as expressed in the appended claims.
WHAT IS CLAIMED IS:
1. A powered threader device comprising:
a frame assembly;
a selectively releasable chuck assembly adapted for retaining and
rotating a workpiece about a workpiece central axis;
a selectively positionable die assembly for forming threads in the
workpiece; and
a brushless DC electric motor supported by the frame assembly, the
motor providing a powered rotary output in selectable engagement with the chuck
assembly to thereby selectively rotate the workpiece.
2 . The threader device of claim 1 wherein the brushless DC electric
motor includes a segmented tooth stator.
3 . The threader device of claim 1 wherein the brushless DC electric
motor is a permanent magnet brushless electric motor.
4 . The threader device of claim 1 wherein the brushless DC electric
motor is a switched reluctance brushless electric motor.
5 . The threader device of claim 1 further comprising a reamer
assembly.
6 . The threader device of claim 1 further comprising a cutter assembly.
7 . A powered threader device comprising:
a frame assembly;
a brushless DC electric motor supported on the frame assembly, the
motor providing a powered rotary output;
a selectively releasable chuck assembly supported on the frame
assembly adapted for retaining and rotating a workpiece about a workpiece
central axis;
a drive train for transmitting rotary motion from the rotary output of
the brushless electric motor to the chuck assembly;
a selectively positionable die assembly supported on the frame
assembly for forming threads in the workpiece; and
control provisions for controlling rotation of the workpiece and
position of the die assembly while forming threads in the workpiece.
8 . The threader device of claim 7 wherein the brushless DC electric
motor includes a segmented tooth stator.
9 . The threader device of claim 7 wherein the brushless DC electric
motor is a permanent magnet brushless electric motor.
10 . The threader device of claim 7 wherein the brushless DC electric
motor is a switched reluctance brushless electric motor.
11. The threader device of claim 7 further comprising a reamer
assembly.
12 . The threader device of claim 7 further comprising a cutter assembly.
13 . A method of forming a thread in a workpiece, the method
comprising:
releasably securing a workpiece in a chuck assembly adapted for
retaining and rotating the workpiece about a workpiece central axis;
contacting a selectively positionable thread forming die with the
workpiece; and
rotating the workpiece by use of a brushless DC electric motor,
whereby upon rotation of the workpiece about the workpiece central axis, the
thread forming die is contacted with the workpiece to thereby form a thread in the
workpiece.
14. A method for monitoring operation of a powered threader device, the
method comprising:
activating the threader device such that the device is placed in
electrical communication with a source of electrical power;
comparing the incoming electrical current to a threshold value,
whereby if the incoming current is less than the threshold value the method is
placed in a hold state, and if the incoming current is greater than the threshold
value the method proceeds to an integrating operation;
integrating electrical current consumed by the threader device as a
function of time during at least a portion of operation of the threader device, to
thereby produce an integration value;
comparing the integration value to at least one benchmark or
archived value stored in an electronic memory unit of the threader device, the
benchmark or archived value selected from the group consisting of a value
representative of a cutting operation, a value representative of a reaming
operation, and a value representative of a threading operation; and
identifying the type of operation performed by the threader device by
determining which of the benchmark or archived values most closely corresponds
to the integration value.
15 . The method of claim 14 wherein the powered threader device
comprises a brushless DC electric motor for performing the identified operation.
16 . A method for monitoring operation of a powered threader device, the
method comprising:
activating the threader device such that the device is placed in
electrical communication with a source of electrical power;
comparing the incoming electrical current to a first threshold value,
whereby if the incoming current is less than the first threshold value the method is
placed in a hold state, and if the incoming current is greater than the first threshold
value the method proceeds to a sensor monitoring operation;
monitoring at least one sensor output of the threader device, the
sensor selected from the group consisting of a cutter sensor, a reamer sensor,
and a thread or die sensor;
comparing magnitude of instantaneous electrical current consumed
to a second threshold value, whereby if the instantaneous current magnitude is
greater than the second threshold value, the method proceeds to another
comparing operation;
comparing an output of the at least one sensor and the
instantaneous electrical current to at least one set of benchmarks or archived
values selected from the group consisting of values representative of a cutting
operation, values representative of a reaming operation, and values
representative of a threading operation; and
identifying the type of operation performed by the threader device by
determining which of the benchmark or archived values most closely correspond
to the output of the at least one sensor and the instantaneous electrical current.
17 . The method of claim 16 wherein the powered threader device
comprises a brushless DC electric motor for performing the identified operation.
18 . A method for performing a threading operation on a workpiece using
a powered threader device, the method comprising:
securing the workpiece in the threader device;
obtaining parameters for the desired threading operation;
determining the target thread length;
confirming existence of appropriate conditions thereby enabling the
threading operation;
rotating the workpiece while secured in the threader device;
contacting and engaging a threading die or tool with the workpiece;
linearly displacing the threading die or tool alongside the workpiece
to thereby form a helical thread;
monitoring the distance of linear displacement of the threading die or
tool;
comparing the distance of linear displacement of the threading die or
tool to the target thread length;
concluding the threading operation upon the distance of linear
displacement of the threading die or tool being equal to or greater than the target
thread length.
19 . The method of claim 18 wherein the threader device includes a
brushless DC electric motor to rotate the workpiece.
20. A method for performing a threading operation on a workpiece using
a powered threader device including a brushless DC electric motor, the method
comprising:
securing the workpiece in the threader device;
obtaining parameters for the desired threading operation;
determining the target thread revolutions;
confirming existence of appropriate conditions thereby enabling the
threading operation;
rotating the workpiece while secured in the threader device by
activating the brushless DC electric motor;
contacting and engaging a threading die or tool with the workpiece;
linearly displacing the threading die or tool alongside the workpiece
to thereby form a helical thread;
monitoring the angular displacement of the brushless DC electric
motor;
comparing the angular displacement of the brushless DC electric
motor to the target thread revolutions;
concluding the threading operation upon the angular displacement of
the brushless DC electric motor being equal to or greater than, the target thread
revolutions.