DESC:FORM-2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13)
Title: SYSTEM AND METHOD FOR AUTOMATIC ADJUSTMENT OF GLASS GRINDING
MACHINE WHEEL
APPLICANT DETAILS:
(a) NAME: Asahi India Glass Ltd
(b) NATIONALITY: IN
(c) ADDRESS: 94.4Kms, NH-8, Village-Jaliawas, Tehsil-Bawal, Distt-Rewari, Haryana, India –
123501.
PREAMBLE TO THE DESCRIPTION:
The following specification particularly describes the nature of this invention and the manner
in which it is to be performed
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SYSTEM AND METHOD FOR AUTOMATIC ADJUSTMENT OF GLASS GRINDING
MACHINE WHEEL
Field of Invention:
[001] The invention relates to dressing of a glass grinding abrasive wheel, and more
specifically for a system and method for automatic adjustment of the abrasive wheel
based upon groove profile position monitoring of the abrasive wheel.
Background of the Invention:
[002] The following background discussion includes information that may be useful in
understanding the present invention. It is not an admission that any of the information
provided herein is prior art or relevant to the presently claimed invention, or that any
publication specifically or implicitly referenced is prior art.
[003] In a glass grinding machine, the grinding is done using an abrasive wheel. After
grinding a number of glasses, the wheel needs to be sent for re-truing to reclaim the
abrasive area. After the truing operation, the position of the new re-profiled groove may
not be at the centre of the wheel as it was when the wheel was new.
[004] In grinding machines around the world it has been witnessed that, adjustment of
the grinding wheel along its axis is done using hit and trial manual operation. This takes
time and requires a skilled operator. There are no instruments right now which can
provide correct position of the groove profile and automate the full process. There is a
need to perform these activities accurately and precisely, automating the whole process
and also saving the job change time as well as reducing wheel setting glass breakages and
improving the process yield.
[005] At present, the process of vertical position adjustment of the wheel is done
manually by an operator using a servo drive. This hit and trial based process rejects up to
two glasses after every wheel change activity, adding to the process yield loss. Setting
grinding wheel after truing is done manually as there are no instruments available which
can give the position of reclaimed groove. Other available products which use sensors to
measure dimensions can’t be used to locate the position of the groove and transmit the
measured data to the machine directly.
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[006] WIPO Patent publication WO2019204215A1 discloses an apparatus for in situ
reworking, e.g., dressing, of a circumferential contact surface of an abrasive wheel. The
apparatus comprises a cutting tool configured to engage with the contact surface and
remove a surface layer from the abrasive wheel of predetermined thickness.
[007] Japanese Patent publication JP3322682B2 addresses to improve the accuracy by
detecting the outer diameter of a work, according a grinding wheel with each axial center
of the work, and making a feed rate of the work so as to be controlled in calculating a
groove bottom diameter from the detected outer diameter, in a groove grinding machine
for an inner ring or the like of a Rzeppa universal joint. The solution includes an outer
diametral size of a pre-machined inner ring 9 (shaftlike work) is measured by a gauge G2
or G'2 as rotating it. This outer diametral size is fed to position compensation motor 4. A
controller C1 calculates a difference with a reference value, shifting a headstock 2 as far
as half of this difference to the side of a spindle 5 or the side of a tailstock spindle 6 and
the inner ring 9 is accorded with each axial center of a grinding wheel 11. In addition,
this measured outer diameter is stored in the controller C1, through which grinding is
started. Even in grinding, the outer diameter is measured and compensated. It is found out
in converting a groove bottom diameter from the measured outer diameter, and this
groove bottom diameter is fed to a gauge G3 or G'3, and a set machining complete point
is modified. A controller C2 controls a feed motor on the basis of modification.
[008] Chinese Patent publication CN101704220A relates to a precise dressing method
of molding grinding wheel of a grinding big-diameter bearing and a flexible device
thereof. The precise dressing method of the molding grinding wheel is that the dressing
motion track of a diamond pen (6) is synthetized through the interpolating and feeding
movement along the axial direction (X shaft) and the radial direction (Y shaft) of the
grinding wheel. The flexible device is mainly composed of a servo driving motor (1), a
harmonicwave reducer (2), a coupler (3), a bearing (4), a spindle (5), an adjusting screw
rod (7), a dial (8) and a support base (9), wherein the diamond pen (6) is installed on the
spindle (5) and the distance (R) of the diamond pen point opposite to the swing center of
the spindle (O-O) is adjusted via driving the adjusting screw rod (7) by the dial (8);
namely, the swing radius of the diamond pen is formed and the servo motor drives the
spindle (5) to drive the diamond pen to swing along the Z shaft; and the flexible device is
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installed on the workbench (10) and is driven by the workbench to realize the
interpolating and feeding movement along the X shaft and Y shaft, and the synthesizing
movement of the X, Y and Z shafts are controlled by PLC. The invention can solve the
problems of low dressing precision of the grind wheel, low matching of the dresser of the
grind wheel in prior art.
[009] US Patent publication US8556680B2 relates to a method and an apparatus for the
automatic edge grinding of glass sheets under clean room conditions, comprising the
following: a) a multi-axis robot at a gripper arm thereof carries a suction frame having a
plurality of suction units for receiving a glass sheet, b) a grinding unit having at least one
rotatable grinding wheel that is supported in a stationary manner is installed in the usable
pivot range of the gripper arm of the robot, c) the ground product occurring during
operation of the grinding unit is extracted by an extraction system, d) the degree of wear
and the state of the grinding wheel are monitored by a calibration device in conjunction
with a detection device, and a computer program for carrying out the method.
[0010] None of the prior arts addressed the problem of setting the wheel automatically,
eliminating any human intervention and thus improving productivity.
Objective of the Invention:
[0011] Primary object of the present invention is to overcome the drawback associated
with the prior systems and methods.
[0012] Yet another object of the present invention is to provide a system and method for
automatic adjustment of the abrasive wheel based upon the groove profile after truing of
the abrasive wheel.
[0013] Yet another object of the present invention is to provide position of groove profile
at its minimum diameter using a servo drive and an optical profile projector.
[0014] Yet another object of the present invention is to locate the position of groove and
using this data to automatically adjust the wheel after a job change to make it symmetric
to the glass.
[0015] Yet another object of the present invention is to measure the gap between matting
surface and the groove point where the diameter is minimum.
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[0016] Yet another object of the present invention is to automatically sent data to the
PLC which instructs the grinding machine to adjust the vertical and horizontal positions
of wheel accordingly.
[0017] Yet another object of the present invention is to send data to the PLC for setting
the wheel automatically, eliminating any human intervention and thus improving
productivity.
[0018] Yet another object of the present invention is to provide both the position and
minimum diameter of the wheel groove and send it to the machine directly.
Detailed Description of Drawing:
[0019] The foregoing detailed description of preferred embodiments, are better
understood when read in conjunction with the appended drawings. For the purpose of
illustrating the invention, there is shown in the drawings exemplary constructions of the
invention; however, the invention is not limited to the specific methods and system
disclosed. In the drawings:
[0020] Figure 1 illustrates a schematic view of a system (100) for automatic adjustment
of glass grinding wheel (102) in accordance with an embodiment of the present
disclosure.
[0021] Figure 2 illustrates a schematic view of a groove G1 before a grinding operation
of the grinding wheel (102), and groove G1’ after the grinding operation of the grinding
wheel (102) in accordance with an embodiment of the present disclosure.
[0022] Figure 3 illustrates a schematic view depicting components of the system (100) of
Figure 1 in accordance with an embodiment of the present disclosure.
Detailed Description of Invention:
[0023] Some embodiments of this invention, illustrating all its features, will now be
discussed in detail.
[0024] The words "comprising," "having," "containing," and "including," and other
forms thereof, are intended to be equivalent in meaning and be open ended in that an item
or items following any one of these words is not meant to be an exhaustive listing of such
item or items, or meant to be limited to only the listed item or items.
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[0025] It must also be noted that as used herein and in the appended claims, the singular
forms "a," "an," and "the" include plural references unless the context clearly dictates
otherwise. Although any systems and methods similar or equivalent to those described
herein can be used in the practice or testing of embodiments of the present invention, the
preferred, systems and methods are now described.
[0026] The disclosed embodiments are merely exemplary of the invention, which may be
embodied in various forms.
[0027] The elements illustrated in the Figures inter-operate as explained in more detail
below. Before setting forth the detailed explanation, however, it is noted that all of the
discussion below, regardless of the particular implementation being described, is
exemplary in nature, rather than limiting.
[0028] The techniques described above may be implemented in one or more computer
programs executing on (or executable by) a programmable computer including any
combination of any number of the following: a processor, a storage medium readable
and/or writable by the processor (including, for example, volatile and non-volatile
memory and/or storage elements), plurality of input units, and plurality of output devices.
Program code may be applied to input entered using any of the plurality of input units to
perform the functions described and to generate an output displayed upon any of the
plurality of output devices.
[0029] Each computer program within the scope of the claims below may be
implemented in any programming language, such as assembly language, machine
language, a high-level procedural programming language, or an object-oriented
programming language. The programming language may, for example, be a compiled or
interpreted programming language. Each such computer program may be implemented in
a computer program product tangibly embodied in a machine-readable storage device for
execution by a computer processor.
[0030] Method steps of the invention may be performed by one or more computer
processors. Suitable processors include, by way of example, both general and special
purpose microprocessors. Generally, the processor receives (reads) instructions and data
from a memory (such as a read-only memory and/or a random access memory) and writes
(stores) instructions and data to the memory. Storage devices suitable for tangibly
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embodying computer program instructions and data include, for example, all forms of
non-volatile memory, such as semiconductor memory devices, including EPROM,
EEPROM, and flash memory devices; magnetic disks such as internal hard disks and
removable disks; magneto-optical disks; and CD-ROMs. Any of the foregoing may be
supplemented by, or incorporated in, specially-designed ASICs (application-specific
integrated circuits) or FPGAs (Field-Programmable Gate Arrays).
[0031] Any data disclosed herein may be implemented, for example, in one or more data
structures tangibly stored on a non-transitory computer-readable medium. Embodiments
of the invention may store such data in such data structure(s) and read such data from
such data structure(s).
[0032] The present disclosure relates to dressing of a glass grinding abrasive wheel, and
more specifically for a system and method for automatic adjustment of the abrasive
wheel based upon wear monitoring of the abrasive wheel.
[0033] Figure 1 illustrates a schematic view of a system (100) for automatic adjustment
of glass grinding wheel (102) in accordance with an embodiment of the present
disclosure.
[0034] In an embodiment, the system (100) for automatic adjustment of glass grinding
wheel (102), comprises following components:
a glass grinding machine (90) having the glass grinding wheel (102);
a servo drive (104) operatively coupled to the glass grinding wheel (102);
an optical profile projector (106) disposed on the glass grinding machine (90);
a servo mechanism (107) operatively coupled to the optical profile projector (106); and
a computing system (108) provided on the glass grinding machine (90), wherein the
computing system (108) is configured to receive inputs from the optical profile projector
(106), and wherein the computing system (108) is configured to operate the servo drive
(104) for adjusting the glass grinding wheel (102) based upon the received inputs.
In an embodiment, the glass grinding wheel (102) includes a groove G1 for receiving and
grinding a glass object (110).
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In an embodiment, the servo drive (104) is coupled to a spindle (112) on which the glass
grinding wheel (102) is mounted, wherein the spindle (112) is rotatable about an axis of rotation,
and the spindle (112) is movable in a direction along a length of the axis of rotation.
In an embodiment, the optical profile projector (106) with the servo mechanism (107) monitors
geometry of the groove G1 before a grinding operation of the grinding wheel (102) over the glass
object (110), and further monitors geometry of groove G1’ after the truing operation of the
grinding wheel (102).
In an embodiment, the inputs received by the computing system (108) from the optical profile
projector (106) includes the geometries of groove G1 and groove G1’.
In an embodiment, the computing system (108) is configured to compute a deviation between the
geometries of groove G1 and groove G1’, and operates the servo drive (104) for adjusting the
glass grinding wheel (102) relative to the glass object (110) based upon the deviation, wherein
the deviation is indicative of a change in minimum diameter and location of the groove G1’ with
respect to the groove G1.
In an embodiment, the glass grinding wheel (102) is adjusted in vertical and horizontal direction.
In an embodiment, the system (100) for automatic adjustment of glass grinding wheel (102)
includes a glass grinding machine (90) having the glass grinding wheel (102). The system (100)
further includes a servo drive (104) operatively coupled to the glass grinding wheel (102). The
system (100) further includes an optical profile projector (106) disposed on the glass grinding
machine (90). The system (100) further includes a servo mechanism (107) operatively coupled to
the optical profile projector (106). The system (100) further includes a computing system (108)
provided on the glass grinding machine (90).
In an embodiment, after grinding a number of glasses, truing needs to be done on the wheel
(102) to reclaim the abrasive area. After the truing operation, the position of new groove (G1’)
may not be at the centre of the wheel as it was in a new wheel (G1). In an embodiment, the glass
grinding wheel (102) includes a groove G1 for receiving and grinding a glass object (110).
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Figure 2 illustrates a schematic view of a groove G1 before a grinding operation by the grinding
wheel (102), and new groove G1’ after the grinding operation of the grinding wheel (102) in
accordance with an embodiment of the present disclosure.
Figure 3 illustrates a schematic view depicting components of the system (100) of Figure 1 in
accordance with an embodiment of the present disclosure.
In an embodiment, the servo drive (104) is coupled to a spindle (112) on which the glass
grinding wheel (102) is mounted, wherein the spindle (112) is rotatable about an axis of rotation,
and the spindle (112) is movable in a direction along a length of the axis of rotation.
In an embodiment, the optical profile projector (106) with help of the servo mechanism (107)
monitors geometry of the groove G1’ after the truing operation of the grinding wheel (102). The
projector (106) with the help of servo mechanism (107), locates position of grinding wheel
groove G1’ from the matting surface. The optical profile projector (106) measures the gap
between matting surface and the groove point where the diameter is minimum.
In an embodiment, the computing system (108) is configured to receive inputs from the optical
profile projector (106). In an example, the inputs received by the computing system (108) from
the optical profile projector (106) include the position of groove G1 and groove G1’ where the
groove diameter is minimum and the minimum diameter at that point. The data inputs is
automatically received by a PLC of the computing system (108) which instructs the grinding
machine (90) to adjust the vertical and horizontal positions of the wheel (102) accordingly.
In an embodiment, the computing system (108) is configured to compute a deviation between the
geometries of groove G1 and groove G1’, and operates the servo drive (104) for adjusting the
glass grinding wheel (102) relative to the glass object (110) based upon the deviation, wherein
the deviation is indicative of a change in minimum diameter and location of the groove G1’ with
respect to the groove G1. In an embodiment, the glass grinding wheel (102) is adjusted in
vertical and horizontal direction. Accordingly, the present invention is related to locating the
position of grooves G1 and G1’ and using this data to automatically adjust the wheel (102) after
a job change to make it symmetric to the glass object.
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In an embodiment, the present invention provides a method for automatic adjustment of glass
grinding wheel (102) of a grinding machine (90). The method includes monitoring, by an optical
profile projector (106) and a servo mechanism (107), a geometry of groove G1 of the grinding
wheel (102) before a grinding operation of a glass object (110). The method further includes
performing the grinding operation on the glass object (110). The method further includes
monitoring, by the optical profile projector (106), a geometry of groove G1’ of the grinding
wheel (102) after the truing operation on the glass grinding wheel (102). The method further
includes receiving inputs, by a computing system (108) from the optical profile projector (106),
based upon the geometries of groove G1 and groove G1’. The method further includes
computing, by the computing system (108), a deviation between the geometries of groove G1
and groove G1’. The method further includes operating, by the computing system (108), a servo
drive (104) for adjusting the glass grinding wheel (102) relative to the glass object (110) based
upon the deviation.
In an embodiment, the Invention provides a method for automatic adjustment of glass grinding
wheel (102) of a grinding machine (90), the method comprising the steps of:
o monitoring, by an optical profile projector (106) and a servo mechanism (107), a
geometry of groove G1 of the grinding wheel (102) before a grinding operation of
a glass object (110);
o performing the grinding operation on the glass object (110);
o monitoring, by the optical profile projector (106), a geometry of groove G1’ of
the grinding wheel (102) after the truing operation on the grinding wheel (102);
o receiving inputs, by a computing system (108) from the optical profile projector
(106), based upon the geometries of groove G1 and groove G1’;
o computing, by the computing system (108), a deviation between the geometries of
groove G1 and groove G1’; and
o operating, by the computing system (108), a servo drive (104) for adjusting the
glass grinding wheel (102) relative to the glass object (110) based upon the
deviation.
In an embodiment, the deviation is indicative of a change in minimum diameter and location of
the groove G1’ with respect to the groove G1.
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In an embodiment, the glass grinding wheel (102) is adjusted in vertical and horizontal direction.
It may be understood by a person skilled in the art that although the subject matter disclosed
herein is illustrated with reference to certain embodiments, this is in no way to limit the scope of
the subject disclosed herein which is limited only and the method and system disclosed may be
implemented in embodiments other than those disclosed in this application.

CLAIMS:We Claim:
1. A system (100) for automatic adjustment of glass grinding wheel (102), the system
comprising:
a glass grinding machine (90) having the glass grinding wheel (102);
a servo drive (104) operatively coupled to the glass grinding wheel (102);
an optical profile projector (106) disposed on the glass grinding machine (90);
a servo mechanism (107) operatively coupled to the optical profile projector (106); and
a computing system (108) provided on the glass grinding machine (90), wherein the
computing system (108) is configured to receive inputs from the optical profile projector (106),
and wherein the computing system (108) is configured to operate the servo drive (104) for
adjusting the glass grinding wheel (102) based upon the received inputs.
2. The system (100) as claimed in claim 1, wherein the glass grinding wheel (102) includes a
groove G1 for receiving and grinding a glass object (110).
3. The system (100) as claimed in claim 1, wherein the servo drive (104) is coupled to a spindle
(112) on which the glass grinding wheel (102) is mounted, wherein the spindle (112) is rotatable
about an axis of rotation, and the spindle (112) is movable in a direction along a length of the
axis of rotation.
4. The system (100) as claimed in claim 1, wherein the optical profile projector (106) with the
servo mechanism (107) monitors geometry of the groove G1 before a grinding operation of the
grinding wheel (102) over the glass object (110), and further monitors geometry of groove G1’
after the truing operation of the grinding wheel (102).
5. The system (100) as claimed in claim 1, wherein the inputs received by the computing system
(108) from the optical profile projector (106) includes the geometries of groove G1 and groove
G1’.
6. The system (100) as claimed in claim 1, wherein the computing system (108) is configured to
compute a deviation between the geometries of groove G1 and groove G1’, and operates the
servo drive (104) for adjusting the glass grinding wheel (102) relative to the glass object (110)
based upon the deviation, wherein the deviation is indicative of a change in minimum diameter
and location of the groove G1’ with respect to the groove G1.
7. The system (100) as claimed in claim 1, wherein the glass grinding wheel (102) is adjusted in
vertical and horizontal direction.
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8. A method for automatic adjustment of glass grinding wheel (102) of a grinding machine (90),
the method comprising:
monitoring, by an optical profile projector (106) and a servo mechanism (107), a
geometry of groove G1 of the grinding wheel (102) before a grinding operation of a glass object
(110);
performing the grinding operation on the glass object (110);
monitoring, by the optical profile projector (106), a geometry of groove G1’ of the
grinding wheel (102) after the truing operation on the grinding wheel (102);
receiving inputs, by a computing system (108) from the optical profile projector (106),
based upon the geometries of groove G1 and groove G1’;
computing, by the computing system (108), a deviation between the geometries of groove
G1 and groove G1’; and
operating, by the computing system (108), a servo drive (104) for adjusting the glass
grinding wheel (102) relative to the glass object (110) based upon the deviation.
9. The method as claimed in claim 8, wherein the deviation is indicative of a change in minimum
diameter and location of the groove G1’ with respect to the groove G1.
10. The method as claimed in claim 8, wherein the glass grinding wheel (102) is adjusted in
vertical and horizontal direction.