FORM 2
THE PATENTS ACT 1970
39 OF 1970
&
THE PATENT RULES 2003
COMPLETE SPECIFICATION
(SEE SECTIONS 10 & RULE 13)
1. TITLE OF THE INVENTION
“THROTTLE POSITION SENSOR”
2. APPLICANTS (S)
(a) Name: Varroc Engineering Limited
(b) Nationality: Indian
(c) Address: L-4, Industrial Area,
Waluj MIDC, Aurangabad-431136,
Maharashtra, India
3. PREAMBLE TO THE DESCRIPTION
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in
which it is to be performed.
2
CROSS-REFERENCE TO RELATED APPLICATIONS
This Application is a PCT National Phase Application of PCT/IN2015/000449 and is a
divisional application of the original parent application no. 201727024378, which was filed
on July 11, 2017.5
FIELD OF THE INVENTION
The invention relates to throttle position sensor for controlling the speed in two wheelers
motorcycles, and three wheelers.10
The invention relates to throttle position sensor with non-contact type dual output sensor
having dual Hall elements in single chip (single IC; single integrated circuit) which
operates on independent dual power supply and single magnet integrated in rotor which
converts rotation angle into two concurrent analog output voltage signals, one of which is a15
master signal to be used by vehicle ECU for vehicle speed control and other is redundant
signal, which is to be continuously monitoring by ECU for diagnostic purpose. This
enhances engine performance through electronic control and increases efficiency of bike in
terms of mileage.
20
BACKGROUND OF THE INVENTION
Conventionally, in motorcycles the throttle cables and throttle pipes are used to operate,
open and close the inlet valves of carburetor which supplies air and fuel mixture to the
engine.25
Potentiometric throttle position sensors have replaced conventional throttle cable
mechanism in electrical bikes. But potentiometric throttle position sensor devices also have
drawbacks of more significant wear and tear when used for throttle position sensor
application. The harsh environmental conditions to which throttle position sensors are30
exposed include high temperatures, intense vibrations, shocks transmitted by the vehicle
running on rough roads and exposure to various liquids and gases, all of which can lead to
early failure of the potentiometers. Finally, being a passive device, neither wire breakages
3
nor over-voltage nor internal defects can be detected and communicated to the ECU
(Engine Control Unit) by the potentiometers.
Improvement over potentiometric throttle position sensors has been provided by non-
contact throttle position sensors wherein the magnetic non-contact type throttle position5
sensors are mounted on handle bar. The mechanism of action is that the angular movement
of a magnet is sensed by Hall Effect IC (integrated circuit) by sensing change in magnetic
field of the magnet i.e. change in magnetic flux density value in non-contact manner with
preloaded programmable Flash Memory within the Hall Effect IC so as to detect rotation
angle of the throttle position sensor. The angle change arising from the rotating movement10
of magnet results in change in flux density value through neutral axis formation at the
center of the magnet having equal amount of flux density at top & bottom surface of the
magnet having north and south pole attraction which is sensed by sensor in 360 degree
angular sensing mechanism by the hall effect IC. For this application, special throttle
position sensor needs to be developed with a magnet designed specifically for that purpose15
and Hall Effect IC, to be mounted (fitted) on handle bar.
US4893502 disclosed an angle sensor for a throttle valve of an internal combustion engine,
comprising: a permanent magnet disposed on one end of the shaft of the throttle valve so as
to generate a parallel magnetic flux and so that the direction of the magnetic flux rotates20
with the rotation of said throttle valve shaft; a throttle body accommodating said throttle
valve; a cavity formed as an integral part of said throttle body to freely rotatably
accommodate said permanent magnet and communicating with a bore through which said
throttle valve shaft extends; a magneto-sensitive element in the form a magneto-resistive
element disposed in said cavity in a relation substantially parallel to the magnetic-flux25
appearing surface of said permanent magnet and spaced apart from said permanent magnet
so as to undergo a change in resistance in response to a change in the magnetic flux density
as a result of the rotation of said permanent magnet; and an electrical circuit including an
amplifier for receiving and amplifying the output of said magneto-sensitive element so as
to convert a detected change in said magnetic flux density into a corresponding change in30
an electrical signal and including means for detecting a change in the resistance value of
said magneto-resistive element and producing an electrical signal corresponding to the
detected change in the direction of said magnetic flux, thereby converting the resistance
4
value of said magneto-resistive element into a corresponding electrical signal, and means
for separately adjusting the zero level of an output signal of said amplifier and adjusting
the amplification factor of an input signal of said amplifier. The said magneto-sensitive
element used in this patent is disclosed in claim 2 as a Hall effect element.
5
A Hall effect sensor is a transducer that varies its output voltage in response to a magnetic
field. Hall effect sensors are used for proximity switching, positioning, speed detection,
and current sensing applications (https://en.wikipedia.org/wik^ all_effect-
sensor#cite_note-1).
10
Thus, for the first time there was available a non-contact type electronic throttle position
sensor that allows ECU (Engine Control Unit) to operate valves of engine through
electronic control. This enhances engine performance and increases efficiency of bike in
terms of mileage. The noncontact type Hall Effect sensors have advantages such as no
wear and tear, more reliability, and better signal to noise ratio when compared to the same15
from potentiometric sensors. This basic feature was further improved by adding safety
features and to make construction of the throttle position sensor more accurate, more
efficient, safer an simpler in construction, to use and repair. Since a motorcycle is subject
to considerable shocks and vibration during its riding, a solution that takes the throttle
position sensor closer to a combination of maximum possible simplicity in20
construction/assembly with increasing/improving accuracy in the output voltages is
considered as most ideal.
Further improvements in no-contact type throttle position sensor have been on record as
given in the following.25
US6978694 (column 4, lines 38-50) discloses in FIG. 1-3, the first throttle controller 21
further includes a sensor 48 on the housing 12 that generates an electrical output
representative of an instantaneous angular position of the shaft 20 relative to the housing
12. While the sensor 48 is coupled to the shaft 20 in any suitable manner, in the first30
throttle controller 1, the sensor 48 is a rotary Hall effect sensor that is responsive to a
magnetic field generated by a magnet 50 disposed in an end 52 of the shaft 20. In this
5
manner, the sensor 48 is inherently less susceptible to misalignment due, for example, to
tolerance variation.
US 20050251301 disclosed throttle grip apparatus comprising: a throttle grip rotatably
mounted on a tip portion of a steering bar of a vehicle; an interlocking portion penetrated5
through the steering bar and rotated in conjunction with the throttle grip; a magnet
provided at an edge portion of the interlocking portion; and an angle sensor arranged
opposite to the magnet and penetrated through a mounting hole on the steering bar. The
angle sensor senses a change in magnetic fields of the magnet in a noncontact manner so as
to detect a rotation angle of the throttle grip based upon the sensed value of the magnetic10
field. The engine of the vehicle is controlled based upon the detected value of the angle
sensor. The mounting hole is formed in a switch case arranged in the vicinity of a base end
of the throttle grip. The angle sensor is molded by a resin.
US8278912 discloses a twist-grip control device (1), for motor vehicles, comprising a15
stator portion (2) which is stationary in operation, a rotor portion (3) which is configured to
be gripped and which is mounted such as to be manually rotatable about an axis (A-A)
with respect to the stator portion (2), against the action of resilient opposing means (13)
tending to recall the rotor portion (3) into a relative angular rest position, first and second
permanent magnet means ( 11a, 11b) connected to the rotor portion (3) in respective20
separate angular fields about said axis (A-A) and configured to generate respective
predetermined angular distributions of magnetic field intensity about said axis (A-A), first
and second magnetic field sensors (14a, 14b) connected to the stator portion (2) in
respective separate angular positions about said axis (A-A), and associated with the first
and second permanent magnet means ( 1a, 11b) respectively in order to provide, when the25
rotor portion (3) is rotated by a certain angle with respect to the stator portion (2), a
respective first and second electrical signal indicating the relative angular position of the
rotor portion (3), the first and second signals being correlated with one another in a
predetermined relationship such that one of the signals is used as a control signal indicative
of the extent of an associated controlled physical magnitude required by the user, and the30
other signal is used as a control signal to enable detection of the occurrence of operating
malfunctions or failures when these signals are no longer correlated with one another in the
predetermined relationship; and further comprising at least one further sensor means
6
associated with the magnets (14a, 14b) to provide a further signal in respect of the angular
position field of the rotor portion (3) corresponding to a range of operation at idling speed
of the engine of the motor vehicle.
Thus due to dual redundant output characteristics of US8278912 it was possible to provide5
wire breakage detection and short circuit detection in ECU.
US8,336,423 discloses a throttle grip apparatus comprising: a throttle grip rotatably
mounted on a leading end of a handle bar of a vehicle; a magnet rotatable together with the
throttle grip; a detector configured to detect variations in a magnetic field of the magnet in10
a non-contact manner to detect a rotation angle of the throttle grip based on a detected
value of the detector; a frictional plate configured to generate a resistance to a rotation of
the throttle grip to generate a rotation load of the throttle grip; a resistance adjusting unit
configured to adjust the resistance generated by the frictional plate, wherein an engine of
the vehicle is controlled based on the detected value of the detector, wherein the frictional15
plate is disposed within the handle bar, and wherein the resistance adjusting unit is
operable from an outside of the throttle grip, and includes an adjusting member disposed
within the handle bar and an urging member disposed between the frictional plate and the
adjusting member, wherein the resistance adjusting unit causes the adjusting member to
move in a direction away from the frictional plate to decrease the urging force of the20
urging member applied to the frictional plate and causes the adjusting member to move in
a direction toward the frictional plate to increase the urging force of the urging member
applied to the frictional plate in order to change the resistance of the frictional plate.
727/DEL/2011 has disclosed an electric throttle grip for motorcycle, comprising: a throttle25
grip assembly comprising a throttle pipe rotatably mounted on handle bar of the
motorcycle and a throttle grip provided on the throttle pipe for manually rotating the
throttle pipe; a throttle position sensing assembly comprising: an first part and second part
forming a casing encasing an inner end of the throttle pipe; a magnet-holder secured with
the throttle pipe so that the throttle pipe and the magnet holder is rotatable together about a30
common axis against a force of a torsion spring; a sector magnet accommodated in a recess
provided on the magnet holder; a sensor assembly disposed in the second part of the
casing, the sensor assembly comprising two magnetic field sensors located adjacent to each
7
other so as to receive equal amount of magnetic flux at given angular position of the
throttle pipe thereby providing two outputs indicative of the angular position of the throttle
pipe.
In 727/DEL/2011, the sensor Assembly comprises of two Hall elements precisely located5
inside IC-holder and electrically connected to a PCB. The 727/DEL/2011 identifies the
drawbacks of US200902010 (now USUS8278912) as: a) complicated design and
construction of twist grip Positional accuracy of magnet 1 and magnet 2 needs to be
maintained which is critical. Semicircular shape of PCB is complicated for manufacturing
and cosily, b) Correlation between signal 1 and signal 2 is not accurate as variations in10
magnetic flux density for 2 magnets are different, c) Excessive errors are involved in
synchronization of signal 1 and signal 2. However, the construction of the sensor assembly
and precise location of the two Hall elements inside IC holder and further integration of
this in the throttle sensor construction is a complicated job. So far as accuracy of
correlation between signal arid signal 2 is concerned, that is not so much of a problem even15
in the prior art design of US8278912 since that can be solved by programming alone. For a
vehicle like motorcycle which is always subject to continuous vibrations and occasionally
bumpy rides, placing two Hall elements inside IC-holder and then electrically connecting
the same to a PCB as provided in 727/DEL/2011 shall be inherently prone to repeated
failures, since the effects of vibrations would tend to disrupt the connection between them20
and the PCB.
Thus, the objective of a simpler and robust throttle grip construction was not achieved in
727/DEL/2011 as required and it only provided an alternative design to US200902010
(now US US8278912).25
SUMMARY OF THE INVENTION
This invention embodies a single piece magnetic field sensor component part comprising a
printed circuit and a Hall Effect IC (Integrated Circuit). In one embodiment, the single30
piece magnetic field sensor component part wherein a Hall Effect IC is soldered directly on
a Printed Circuit Board or integrated as one piece with the Printed Circuit Board without
requirement of an Integrated Circuit (IC) holder between the Hall Effect IC and the Printed
8
Circuit Board. In the embodiment of this invention, the Hall Effect IC, mentioned above,
comprises two in-built separately programmable Hall Elements, the two Hail Elements
being designated herein as Die A and Die B.
In another embodiment, this invention comprises an automobile component comprising a5
single piece magnetic field sensor component part comprising a printed circuit and a Hall
Effect IC (Integrated Circuit). The invention also comprises the automobile component
wherein a Hall Effect IC is soldered directly on a Printed Circuit Board or integrated as one
piece with the Printed Circuit Board without requirement of an Integrated Circuit (IC)
holder between the Hall Effect IC and the Printed Circuit Board. The Hall Effect IC in the10
automobile component of this invention comprises two in-built separately programmable
Hall Elements, the two Hall Elements being designated herein as Die A and Die B. The
automobile component of this invention is a means for controlling the performance of the
engine control unit (ECU) of the automobile via sensing the change in magnetic flux
density, generated by a relative positional change of a magnet due to rotation of a throttle15
of the automobile mounted on its handle, by the Hall Effect Sensors to generate two
independent analog output signals which are proportional to the magnitude of the relative
positional change and these signals are conveyed to the ECU. The automobile component
of this invention described above may include one or more components selected from the
list consisting of a throttle position sensor comprising a throttle position sensor, clutch20
comprising a clutch position sensor for Clutch pedal position sensing or, for gear
comprising a neutral gear position sensor and the like.
A throttle position sensor assembly (Figure 1) of this invention comprises of following
major sub-assemblies: (a) upper case (6) complete with screws (7a) and (7b), (b) rotor25
complete assembly (FIG - 11) comprising rotor (3) and magnet (4) fitted to a throttle pipe
(1) and friction plate/ring (2) to make a throttle pipe assembly, a torsion spring (5), (c)
lower case complete assembly [comprising insert nuts (8a, 8b), locating pin (9) and lower
case (10)], and (d) single piece magnetic field sensor component part comprising a printed
circuit (12), a Hall Effect IC (Integrated Circuit) (11), a wiring harness (13), and a cable30
Tie (15). The Hall Effect IC consisting of two Hall elements Die A (11a) & Die B (11b)
being precisely located inside Hall Effect IC.
9
The rotor complete assembly comprises of rotor and NdFeB magnet, the friction plate/ring
is assembled with throttle pipe, rotor complete assembly is engaged with throttle pipe
through Oldham coupling mechanism, freely rotates inside throttle position sensor
assembly and torsion spring assists to retain its initial position after the throttle pipe is
released, the use of friction plate/ring ensures giving a smooth feeling of throttle pipe when5
it is manually rotated by vehicle rider, the single piece magnetic field sensor component
part comprising a printed circuit and a Hall Effect IC (Integrated Circuit) is soldered to a
wiring harness, and being further fitted in lower case by inserting it in pocket provided in
lower case, covered with potting material and wiring harness fitted with cable tie. A
specific gap relation is maintained between Hall Effect IC and magnet fitted in the Rotor,10
the throttle pipe assembly being finally enclosed inside lower case complete assembly and
upper case, lower case complete and upper case are clamped with each other on handle bar
by two screws. While one Die of Hall Effect IC is programmed to sense the magnetic flux
density value of magnet and gives a first output signal (OUT1) with respect to angular
movement of throttle pipe from 0 degree to 85 degrees which is master output to ECU, at15
the same time the other Die B of Hall Effect IC is programmed and is used for giving
second output signal (OUT2) with respect to angular movement of throttle pipe from 0
degree to 85 degrees for redundancy purpose for serving as diagnostic signal to ECU. The
Hall Effect IC is programmed with 16 or 6 point calibration method. The throttle position
sensor using single NdFeB Magnet is magnetized in such a way that it has neutral axis20
formation at the center of the magnet, and the two arching sides on the two sides of the
center of the magnet have opposite polarities [North (N) and South (S)] on outer and inner
portion/surface of the arc/arch in such a way that if on one side North pole is on the upper
side and South pole is on the lower side, on the other side, South pole is on the upper side
and north pole is on the lower side; as illustrated in Figure 7.25
The throttle position sensor of this invention as described above comprise the lower case
complete assembly and an upper case assembly which are stationary; the rotor complete
assembly is assembled with throttle pipe and is mounted in throttle position sensor in such
a way that it can be manually rotated from 0 to 85 degrees with respect to case fitted on30
handle bar, a permanent magnet is fitted into rotor cavity to generate respective
predetermined angular distributions of magnetic flux density over the Hall Effect IC.
10
Both Die A and Die B of throttle position sensor of the instant invention operate on
independent +5V power supply with individual Ground connections; whereas the first
output signal gives an linear analog output signal (OUT1) of from 0.5V to 4.5V, the second
linear analog output signal (OUT2) gives an output of from 0.25V to 2.25V and vice versa
when throttle pipe is rotated in counter-clock-wise and clock-wise direction, these two5
independent analog outputs being achieved by programming both Die A and Die B inside
of the Hall Effect IC through an external programming device (Tool-GUI) Universal
programming tool for software programming purpose The PTC-04 programmer was
designed for efficient, precise calibration of the Hall Effect programmable ICs. The
programmer is designed to be easily adapted to a standard PC and to an application module10
to allow calibration of programmable sensor ICs within the operating environment. The
PTC-04 programmer contains its own programmable power supply and measurement
circuitry. The programmer is similar to a standard EEPROM programmer, but adds many
special features such as 16 bit voltage and current measurement capability, and
configuration options that will accommodate users from the prototyping phase directly into15
production. An compatible PC is required to load software to the programmer and control
the functions of the programmer, and which distinguishes first and second output
characteristics by providing and filling adequate parameters in the GUI to each Die with
respect to magnetic flux density sensed by each Die during angular movement of the
magnet fitted in the rotor while rotating along with the throttle pipe, the Hall Effect IC20
being an axis position sensor which senses magnetic flux density of magnet in lengthwise
(X), lateral (Y) and vertical (Z) direction of magnet. The analog voltage outputs of each of
the two Dies, Die A and Die B, linearity of the Throttle Position Sensor being maintained
within ±2% linearity over its entire operating range. The throttle position sensor
construction is designed to fit within 27-30 mm range in addition to the length of throttle25
pipe, the response time of the throttle position sensor in CCW direction when throttle pipe
is fully rotated to 85 degree is 36 milliseconds or less. The Hall Effect IC gives less
response time in clock wise direction, i.e. the movement of throttle pipe from 85 degrees to
0 degrees position. The output response time of Hall Effect IC of is 36 milliseconds,
Output from Die A is 0.5 volts at 0 degree rotation to 4.5 volts at 85 degree rotation of the30
throttle pipe, and Output from Die B is 0.25 volts at 0 degree rotation to 2.25 volts at 85
degree rotation of the throttle pipe which is exactly half of the output Die A. The co-
relation between two outputs from Die A and Die B is accurately maintained, The
11
collective dimensional variation of throttle pipe, rotor, magnet, single piece magnetic field
sensor component part comprising a printed circuit and a Hall Effect IC (Integrated
Circuit) being not more than ±0.40 mm, the magnet width is 1 mm more than Hall Effect
SC. The magnet used in the throttle position sensor in this invention has following
properties: material : NdFeB. Arc type, grade: N35, magnetic flux Density - with Gauss5
Value : 1500 +/- 500 gauss, magnetized in such a way that it has neutral axis formation at
the center of the magnet, and the two arching sides on the two sides of the center of the
magnet have opposite polarities [North (N) and South (S)] on outer and inner
portion/surface of the arc/arch in such a way that if on one side North pole is on the upper
side and South pole is on the lower side, on the other side, South pole is on the upper side10
and north pole is on the lower side; as illustrated in Figure 7. The dimensions of parts of
throttle position sensor are maintained in a range of ±0.10 mm.
The automobile in which the component of this invention is used comprises a two wheeler
or a three wheeler. The automobile component for which this invention has been illustrated15
is a throttle position sensor comprising a throttle position sensor.
This invention also comprises a mechanical means for reducing friction between two parts,
at least one of the parts is moving against the other; wherein the mechanical means is not a
ball bearing. The mechanical means comprises a ring of a wear resistant material that20
provides a line contact to the stationary part/s. The mechanical means may have a "V"
shape in a cross section having a first arm that comes in contact with the stationary part/s
and a second arm, wherein both the arms of the "V" are at 90° angle to each other and the
surface of first arm of "V" is provided with a projecting curvature made in such a way that
when it comes in the contact with the stationary part/s, the contact is established along the25
line of circumference provided by the projecting curvature, thereby reducing the
abrasion/friction. In one embodiment, the wear resistant material of the mechanical means
is polyacetal; however, any other wear resistant material may be used, if appropriate to the
application. The said at least one moving part is the friction ring and the stationary parts
may comprise lower case and upper case of a position sensor of an automobile. The30
position sensor of an automobile, illustrated herein, is a throttle position sensor; however,
the friction ring of this invention may be used in any other application wherein there is an
abrasion between two surfaces occurring on account of movement of at least one of them;
12
including a rotating movement. The automobile may be a two wheeler or a three wheeler.
The throttle position sensor of this invention comprises of following major sub-assemblies:
(a) upper case (6) complete with screws (7a) and (7b), (b) rotor complete assembly
comprising rotor (3) and magnet (4) fitted to a throttle pipe (1) and friction plate/ring (2) to
make a throttle pipe assembly, (c) lower case complete assembly [comprising insert nuts5
(8a, 8b), locating pin (9) and lower case (10)], and (d) single piece magnetic field sensor
component part comprising a printed circuit (12) and a Hall Effect IC (Integrated Circuit)
(11) and a wiring harness (13), the Hall Effect IC consisting of two Hall elements being
precisely located inside Hall Effect IC called as Die A (11a) and Die B (11b).
10
BRIEF DESCRIPTION OF FIGURES AND LEGENDS
Description of legends: (1) Throttle pipe, (2) The Friction plate/ring, (3) Rotor, (4) Magnet,
(5) Torsion Spring, (6) Upper Case, (7a and 7b) Screws, (8a and 8b) Insert Nuts, (9)
Locating Pin, (10) Lower Case, (11) Hall Sensor IC, (12) Printed Circuit, (13) Wiring15
Harness, (14) Chip Resistors and Chip Capacitors, (15) Cable Tie, (16) Line of contact
between the friction ring surface and the surface of the lower case and the upper case, (20)
Magnet neutral axis in FIG-7.
Figure 1: Illustrates construction of throttle position sensor assembly.20
Figure 2: Illustrates front, back and side view (Left & Right) of throttle position sensor
without wiring harness- FIG-2.3 (F) Front view, Side view FIG-2.4 (R) Right view & FIG-
2.2 (L) Left View.
FIG-2.1 (B) back view.
Figure 3: Illustrates an isometric view of the throttle position sensor.25
Figure 4: Illustrates the throttle position sensor lengthwise-sectional view taken along axis
X -Y.
Figure 5: Illustrates the throttle position sensor lengthwise-sectional perspective view taken
along axis X-Y.
Figure 6: Illustrates the throttle position sensor enlarged length wise sectional perspective30
view taken along axis XA7Z.
Figure 7: Illustrates Arc Magnet Design with magnet poles (S & N) and Neutral axis
formation at center.
13
Figure 8: Illustrates the throttle position sensor output voltage characteristics graph relation
between angular movements of throttle pipe Vs two individual voltage outputs from Die A
and Die B showing redundant output characteristics with linearity error limits within ±2%..
Graphical characteristics (i) Output 1 (from Die A), (ii) Output 2 (Redundant Output, from
Die B)5
Figure 9: Friction plate/ring use for smooth feeling of throttle pipe rotating in throttle
position sensor. Throttle pipe, (2) The Friction plate/ring, (3) Rotor, (6) Upper Case.
Elliptical circle area shows line contact between friction plate/ring arid upper case.
Figure 10: The output voltage response time of Hall Effect IC when throttle pipe rotated in
counter-clock-wise direction.10
Figure 11: Illustrates rotor complete assembly comprising rotor (3) and magnet (4).
Figure 12: Illustrates throttle pipe assembly comprising (1) Throttle pipe (2) Friction
plate/ring, (3) Rotor, (4) Magnet.
Figure 13: Illustrates lower case complete comprising (1) Throttle pipe (2) Friction
plate/ring, (3) Rotor, (5) Spring, (8a) and (8b) Nut inserts, (9) Locking pin, (10) case15
lower.
Figure 14: Illustrates single piece magnetic field sensor component part comprising (11)
Hall Effect IC, (12) Printed circuit, (13) Wiring harness & (14) component resistance and
capacitor
20
Figure 15: Illustrates friction ring of this invention with magnification of the surface of the
ring that comes in contact with stationary parts of lower case and the upper case when
throttle pipe is rotated.
DETAILED DESCRIPTION OF THE INVENTION25
This invention comprises a single piece magnetic field sensor component part comprising a
printed circuit and a Hall Effect IC (Integrated Circuit). The said single piece is
conveniently made by soldering a Hall Effect IC directly on a Printed Circuit Board
without requirement of an Integrated Circuit (IC) holder between the Hall Effect IC and the30
Printed Circuit Board. Any other method may also be used to achieve an integration of a
Hall Effect IC directly on a Printed Circuit Board into one single piece. In one
14
embodiment, the Hall Effect IC comprises two in-built separately programmable Hall
Elements, the Hall Elements being designated herein as Die A (11a) and Die B (11b).
"Integration" into one single piece, for the purpose of this specification, is defined as
converting the two physically separate units functioning separate from each other in to a5
physically "single piece" an performing a single function by means of creating a permanent
physical bond between the two separate components such that the original two components
cannot be retrieved in their original forms by eliminating the physical bond; or when
subjected to any kind of vibrations, there is no movements between any portions of the two
components relative to each other. Thus, in the instant case, the "integration" of the printed10
circuit and the Hall Effect IC is envisaged to be to such a perfection that when an
automobile is running with this single piece magnetic field sensor component part
comprising a printed circuit and a Hall Effect IC (Integrated Circuit) in one of its moving
components, in no circumstances in course of normal running, the vibrations should make
the Hall Effect IC to vibrate at a different rate than the printed circuit itself. For further15
clarification, for example, screwing or nut-bolting or clamping together of two components
or plugging together of two components does not convert them into a "single" piece within
the meaning envisaged herein; it becomes "an assembly" in which the individual identity
of both the parts is maintained in the sense that they can be dismantled by unscrewing, or
removing the bolts or by removing the clamp or by unplugging them from each other.20
When an assembly is subjected to vibrations, each of its component part shall vibrate
independent of each other. Conveniently and reliably, the integration is done by soldering.
However, any other method of integration may also be used.
This invention also discloses a throttle position sensor assembly used for governing the25
speed in automobiles. The automobiles comprise two and three wheelers. When throttle
pipe assembly is rotated, the throttle position sensor assembly converts rotational
movement of throttle pipe consisting a NdFeB Magnet having magnetic flux density into
analog voltage outputs by using Hall Effect Sensor technology; the Hall Effect Sensor
technology senses change in magnet flux density. The single piece magnetic field sensor30
component part comprising a printed circuit and a Hall Effect IC (Integrated Circuit)
comprising two in-built separately programmable Hall Elements, the Hall Elements are
preloaded with a programming software that provides two redundant outputs in response to
15
the change in magnetic flux density, when an arc magnet fitted to a rotor rotates above
them. It is an embodiment of this invention that the Throttle position sensor has the said
single piece magnetic field sensor having two independent Die component part. This
feature provides an unmatched accuracy and reliability against any failures that can
potentially arise due to vibration and shocks. Normally, the single piece magnetic field5
sensor component part is protected from environmental effects such as moisture, water
insertion etc. by application of conformal coating material used for anti-oxidation purpose
of solder Joint on the single piece magnetic field sensor component part and the use of
epoxy potting material for filling in a pocket where the single piece magnetic field sensor
component part is fitted in Lower Case. Epoxy potting material solidifies after passing10
through oven for 30-45 minutes. t also ensures protection of location of single piece
magnetic field sensor component part and ultimately location of Hall Effect IC in the
single piece magnetic field sensor component part in Lower case with respect to NdFeB
magnet the rotor, from vibrations of the vehicle. Epoxy potting material additionally
protects the single piece magnetic field sensor component part from environmental effects15
also.
Usually ICs have small size. In the illustration of this invention here7 the size of IC is 4.4
X 5 X 1.1 mm ±0.1 mm, the size of the "Die A" (first Hall element) is 1.91 ±0.1 mm, and
that of "Die B" (second Hall element) is 2.86±0.1 mm' the distance between two Hall20
elements is 0.9±0.1 mm. However, these sizes and distance mentioned above can vary
within reasonable limits as long as both the Hall elements are so located with respect to
each other that they shall get same magnetic flux. In an illustrative embodiment, the width
of C is 5 mm whereas width of magnet is 6 mm. It results in more reliability in terms of
sensing the same magnetic flux density value over the Die A and Die B at a given angular25
rotation of throttle pipe i.e. angular rotation of magnet.
Throttle position sensor consists of Lower Case complete assembly and Upper Case, which
are stationary; a rotor assembled with Throttle Pipe is mounted in between lower case &
upper case in such a way that it can be manually rotated from 0 to 8 degrees with respect to30
case fitted on handle bar. A permanent arc magnet is fitted into rotor cavity to generate
respective predetermined angular distributions of magnetic flux density over the Hall
Effect IC.
16
Rotor Inside the upper case rotates from 0 to 85 degrees in between two stoppers provided
in Case Upper. Rotor is engaged with throttle pipe by Oldham coupling mechanism,
angular movement of the throttle pipe assembly along with handle bar axis which results in
angular movement of magnet inside the rotor over the top surface with respect to Hall
Effect IC. The Throttle Position Sensor uses Hall Effect IC having two Hall elements,5
called as "Die A" and "Die B", which are programmable type and are programmed in
specific manner to get single, linear output signals from Die A with respect to angular
rotation of throttle pipe, which will be provided to ECU (Engine Control Unit) as master
output and second single, linear output signals from Die B with respect to angular rotation
of throttle pipe is Redundant signal output which is used as diagnostic input to ECU for10
continuously monitoring of throttle position sensor output purpose. An arc magnet with
angular length of 104 degree (32.2mm), width "6mm" and thickness of 3mm having
optimized gauss value of 500± 500 Gauss which is specifically selected to provide long
time period sufficient Magnetic flux density over Hall Effect IC, and magnetized in such a
way that it has neutral axis formation at the center of the magnet, and the two arching sides15
on the two sides of the center of the magnet have opposite polarities [North (N) and South
(S)] on outer and inner portion/surface of the arc/arch in such a way that if on one side
North pole is on the upper side and South pole is on the lower side, o the other side, South
pole is on the upper side and north pole is on the lower side; as illustrated in Figure 7.
Magnet is located in slot provided in Rotor.20
Another objective of the invention is to use this Non-Contact Throttle Position Sensor for
dual independent output with analog voltage variations with respect to angular position of
magnet. Die A is to provide analog signal as master output voltage to ECU and Second Die
B provide second analog signal as a redundant output voltage to ECU to provide diagnostic25
feature to overcome master output failure detection remedy to increase reliability of the
product.
Providing smooth operation of throttle position sensor is also another objective for taking
up this inventive work.30
Following are the steps of construction of throttle position sensor of this invention:
17
The friction plate/ring (2) is assembled with throttle pipe (1) by twisting it and applying
glue on its mating surface. The function of friction plate/ring (2) is to provide less friction
with lower case (10) and upper case (6) when throttle pipe (1) is operated. Magnet (4) is
press fitted in pocket provided in rotor (3). Pocket provided in rotor has crush ribs which
are used to ensure that magnet (4) is not loose fitted in rotor (3) and later on magnet is5
safeguarded by epoxy potting material filling process, which protects from environmental
effects such as moisture, humidity, water insertion/immersion, temperature, etc. and
possible breakage of magnet if vehicle is fallen. This sub assembly is called rotor complete
assembly.
10
FIG-11. Rotor assembly is then assembled with throttle pipe assembly by means of ribs
provided in throttle pipe (1) and pockets provided in rotor (2) with the help of "Oldham
coupling Mechanism". One end of torsion spring (5) is then assembled in a hole provided
in rotor (3). This sub assembly is called throttle pipe assembly FIG-12. Throttle pipe
assembly is then assembled with lower case (10) by inserting other end of torsion spring15
(5) in lower case (10). Lower case (10) is insert molded with Locating Pin (9) and Insert
Nuts (8a and 8b) (2 Nos). This sub assembly is called as lower case complete assembly
FIG-13. Lower case complete assembly is assembled on handle bar by passing handle bar
through holes provided for mounting in rotor (3), Throttle Pipe (1) and opening in lower
case complete (10) and engaging locating pin (9) in mounting hole of handle bar. Upper20
case (6) assembled on top of the lower case complete assembly on handle bar and
tightened with help of screws (7a and 7b) (2 Nos).
The single piece magnetic field sensor component part consists of a printed circuit (12), a
Hall effect Sensor IC (11), wiring harness (13) and other electronic components such25
resistors, capacitors etc. FIG-(14). The single piece magnetic field sensor component part
may be protected from environmental effects during assembly operation by applying
Conformal coating material on the same. The single piece magnetic field sensor
component part (14) is inserted in a pocket provided in lower case (10). Wiring harness
(13) fixed with lower case by tying cable tie (15) around wiring harness (13) and "T"30
shaped feature provided in lower case (10). Epoxy Potting material with proper mixture of
hardner and resin is filled in pocket provided in lower case (10) to protect the single piece
magnetic field sensor component part from circuit damages due to moisture, humidity,
18
water insertion/immersion, temperature, etc. and to protect location of single piece
magnetic field sensor component part i.e. location of Hall Effect IC with respect to magnet
from vibrations of vehicle.
It is an embodiment of this invention is that the electronic throttle position sensor is5
overcome by programming "Die A" and "Die B" with a software programming GUI
(graphical user interface- programming tool) operates on 230V AC, 1 Ph 50~60Hz power
supply which is having inbuilt two dual independent separate +5V power supply lines
totally isolated from each other, (first +5V line is used to VCC1 and GND1 connection
which is also to be used for Die A programming purpose whereas second +5V line is used10
to VCC2 and GND2 connection which is also to be used for Die B programming purpose
such that with respect to angular rotation of throttle pipe ( 1), the first die, "Die A" gives
independent output (OUT1) as master output range from 0.5V to 4.5V and the second die
"Die B" gives a redundant output (OUT2) which gives output voltage range exactly half of
the Die A output i.e. from 0.25V to 2.25V. This objective is directed to ensure maintaining15
functioning of Throttle Position Sensor if Die A fails for any reason, so that the vehicle
does not come to a halt, second Isolated Die B output (OUT2) will provide a redundant
input signal to ECU which is continuously monitoring and used as diagnostic input to ECU
When master output failure is detected.
20
This feature is ensure the driver for safe driving of vehicle so that the vehicle can be safely
controlled and driven at a lesser speed to a safer position with respect to traffic and to a
safer destination o to a place where repairing service is available. This results in increase in
safety of the driver/rider in case of failure of throttle position sensor master output (OUT1)
comes from "Die A" of the Hall effect IC.25
Accordingly, the invention also comprises a throttle position sensor which mainly
comprises of following major sub-assemblies as follows: upper case [comprising (7a) and
(7b) together], rotor complete assembly [Figure 11, comprising rotor (3) and magnet (4)]
fitted to a throttle pipe (1) and friction plate/ring (2) to make a throttle pipe assembly,30
lower case complete assembly [Figure 13; comprising insert nuts (8a, 8b), locating pin (9)
and lower case (10)] and a single piece magnetic field sensor component part [Figure 14;
comprising Hall effect Sensor C ( 11), printed circuit (12) and wiring harness (13)].
19
Rotor complete assembly comprises of rotor and NdFeB magnet. NdFeB magnet is press
fitted in a slot provided in rotor. Crush ribs on rotor ensures tight fitment of NdFeB
magnet. Throttle pipe assembly comprises of throttle pipe, friction plate/ring and rotor
complete assembly. Friction plate/ring is assembled with throttle pipe. Rotor complete5
assembly, which is engaged with throttle pipe through Oldham coupling mechanism, freely
rotates inside throttle position sensor assembly and torsion spring assists to retain its initial
position after the throttle pipe is released. The use of friction plate/ring ensures giving a
smooth feeling of throttle pipe when it is manually rotated by vehicle rider.
10
The single piece magnetic field sensor component part comprises of Hall Effect IC which
is having two Hall elements precisely located inside Hall Effect IC. Hall Effect IC is
electrically connected to the PCB by soldering process. The electrical signal is transmitted
through wiring harness connected to PCB at opposite end by soldering process. The single
piece magnetic field sensor component part is then protected from environmental effects15
by applying conformal coating material on the single piece component. The single piece
magnetic field sensor component part is further fitted in lower case by inserting it i pocket
provided in lower case and covered with Epoxy potting material and wiring harness fitted
with cable tie. A specific gap relation is maintained between Hall Effect IC and magnet
fitted in the Rotor. Throttle pipe assembly is finally enclosed inside lower case complete20
assembly and upper case. Lower case complete assembly and upper case are clamped with
each other on handle bar by 2 screws.
Throttle position sensor uses single NdFeB Arc type magnet magnetized in such a way that
it has neutral axis formation at the center of the magnet, and the two arching sides on the25
two sides of the center of the magnet have opposite polarities [North (N) and South (S)] on
outer and inner portion/surface of the arc/arch in such a way that if on one side North pole
is on the upper side and South pole is on the lower side, on the other side, South pole is on
the upper side and north pole is on the lower side; as illustrated in Figure 7.
30
It is an embodiment of this invention that while one Die A of Hall Effect IC is
programmed to sense the magnetic flux density value of magnet and gives a first output
signal (OUT1) with respect to angular movement of throttle pipe from 0 degree to 85
20
degrees; at the same time the other Die B of Hall Effect IC is programmed and used for
giving second output signal (OUT2) with respect to angular movement of throttle pipe
from 0 degree to 85 degrees for redundancy purpose, (diagnostic signal to ECU). It s a
further embodiment of this invention that both Die A and Die B operate on independent
+5V power supply with individual GND (Ground) connections. Whereas the first output5
signal gives a linear analog output voltage signal (OUT1) of from 0.5V to 4.5V, the second
linear analog output voltage signal (OUT2) gives an output of from 0.25V to 2.25V; and
vice versa when throttle pipe is rotated in CCW (counter-clock-wise) and CW (clock-wise)
direction. These two independent analog outputs are achieved by programming both Die A
and Die B located inside the Hall Effect IC through an external programming device (GUI10
Tool) which distinguishes/defines first and second output characteristics by providing and
feeding appropriate program to each Die through the GUI on relation between the
magnetic flux density sensed by each Die during angular movement of the magnet fitted in
the rotor in relation to the angular movement of the throttle pipe when the throttle pipe is
rotated. The Hall Effect IC is actually Tri axis® Position Sensor which senses magnetic15
flux density of magnet in X, Y and Z direction of magnet by using Tri axis® Hall
Technology. The Hall Effect IC is a monolithic sensor IC sensitive to the flux density
applied orthogonally and parallel to the IC surface. The Hall Effect IC is sensitive to the
three components of the flux density applied to the IC (i.e. BX, BY and BZ). This allows
the IC with the correct magnetic circuit to decode the absolute position of any moving20
magnet (e.g. rotary position from 0 to 360 Degrees or linear displacement, It enables the
design of novel generation of non-contacting position sensors that are frequently required
for both automotive and industrial applications, the three vector components of the
magnetic flux density (BX, BY and BZ) applied to the IC are sensed through the sensor
front end. The respective Hall signals (VX, VY and VZ) are generated at the Hall plates25
and amplified.
Once the position (angular or linear) information is computed, it is further conditioned
(mapped) vs. the target transfer characteristic and it is provided at the output(s) as either a
ratiometric analog output level through a 12 bit DAC followed by a buffer. The30
programming steps do not require any dedicated pins.
21
The operation is done using the supply and output nodes of the IC. The programming of
the Hall effect IC handled by the Melexis Programming Unit PTC-04 with the dedicated
daughterboard and software tools.(User Interface).
It is an embodiment of this invention that both Die A and Die B analog voltage outputs5
(OUT1 and OUT2) linearity of the Throttle Position Sensor is maintained within ±2%
linearity over its entire operating range. It is also an embodiment of this invention that the
dimensions of parts of throttle position sensor are maintained in a range of ±0.10 mm and
by programming Hall Effect IC with 16 or 6 point calibration method. The analog voltage
output linearity is maintained within ±2% linearity over its entire operating range on10
account of use of less number of parts, five only, i.e. throttle pipe, rotor, magnet, PCB and
Hall Effect IC and the control of the dimensions of the throttle position sensor parts within
the range of. ±0.10 mm.
It is also an embodiment of this invention that the collective of dimensional variation of all15
these 5 parts is not more than ±0.40 m whereas magnet width is 1 mm more than Hall
Effect IC to ensure that linearity is maintained within ±2% range over its entire operating
range.
It is also an embodiment of this invention that the throttle position sensor design is20
compact in size. In the illustrative design herein, the throttle position sensor construction is
designed to fit within 27-30 mm range in addition to the length of throttle pipe. The scope
to make the throttle position sensor compact gives an advantage wherein there is a space
constraint for accommodating the throttle position sensor on the handle bar.
25
Operationally, for a driver, if the analog voltage output linearity is not maintained within
±2% over its entire operating range, it results in following disadvantages to the
driver/Rider:
a. Irregular performance of Vehicle.
b. Sudden increase or decrease in speed of vehicle30
c. Inaccurate mileage of Vehicle.
The throttle position sensor of this invention overcomes these, problems.
22
It is an embodiment of this invention that the throttle position sensor provides redundant
operation, if one output fails the other output will ensure normal operation of throttle
position sensor controlled by ECU which leads to increase in reliability of speed control
provided by operation of the throttle position sensor which ultimately provide safety also
to the rider.5
Magnet Details:- The magnets used in the throttle position sensor inside the rotor case.
Magnet has properties described below:
1. Material : NdFeB.10
2. Arc Type
3. Grade : N35
4. Magnetic Flux Density - with Gauss Value : 1500 +/- 500 gauss.
5. magnetized in such a way that it has neutral axis formation at the center of the magnet,
and the two arching sides on the two sides of the center of the magnet have opposite15
polarities [North (N) and South (S)] on outer and inner portion/surface of the arc/arch in
such a way that if on one side North pole is on the upper side and South pole is on the
lower side, on the other side, South pole is on the upper side and north pole is on the lower
side; as illustrated in Figure 7.
20
The material used for throttle pipe is PBT 30% GF (Polybutylene Terephthalate).
However, any other material suitable for this purpose may be used. When throttle pipe
assembly is assembled with lower case and upper case, because of tendency of torsion
spring to come to its original position, throttle pipe is pushed backwards. This results in
friction between throttle pipe ribs and inner surfaces of lower and upper case. Due to the25
operation of the torsion spring, the contact surfaces of the lower case and the throttle pipe
get brushed on each other while rotating the throttle pipe; which results in a rough feel to
the rider, and involves contact along entire flat contact surfaces of the parts of throttle pipe
and the rim of the lower case as well as the upper case which come in contact with each
other. This phenomenon will result in rough movement feeling of throttle pipe when30
operated. To avoid rough movement feeling of throttle pipe, in one embodiment of this
invention, a friction plate/ring is provided which is a ring shaped structure that is located
between the contact surfaces mentioned above, this ring comprises a "V" shape in a cross
23
section having a first arm that comes in contact with the stationary part/s and a second arm,
wherein both the arms of the "V" are at 90° angle to each other and the surface of first arm
of "V" is provided with a projecting curvature made in such a way that when it comes in
the contact with the stationary part/s, the contact is established along the line of
circumference, provided by the projecting curvature, thereby reducing the5
abrasion/friction. This situation gives a very important technological advance/advantage
over prior art wherein the abrasion is between two flat surfaces which are not wear
resistant. Thus, when throttle pipe operates against torsion spring, the only contact between
the surface of the lower case and the upper case and the friction ring is limited to the thin
surface of the convex shaped surface of the friction ring; there is no contact now between10
the flat surfaces of throttle pipe and surfaces o lower case and the upper case. Advantage of
this situation is that there is least of friction generated under pressure of torsion spring, the
feel generated out of the of the rotation of the throttle pipe is smooth and the friction ring
can be made out of wear resistant material providing long life to these moving parts. The
throttle pipe is made from polybutylene terephthalate (30% Glass Filled) and lower and15
upper case are made from Polyamide or nylon (30% Glass Filled), both of which are not
wear resistant. In a further embodiment of this invention, the material used for making the
friction plate/ring is PolyAcetal (POM), which has high wear resistance and self-
lubrication properties. However, any other material suitable for this purpose may be used.
By using Friction plate/ring smooth movement feeling is achieved.20
Persons skilled in the art would immediately understand that a friction ring of this
invention can be used for many analogous and equivalent applications wherein two parts
having relative movement and operating with or without an additional pressure between
them; and all such obvious variations and equivalents of the above disclosed friction ring25
are also considered to be covered within the scope of this invention. The use of such a
friction ring has been illustrated here in case of throttle position sensor assembly; however,
the scope of the invention of friction ring is not limited to the illustration.
In another embodiment of this invention, the response time of the throttle position sensor30
in CCW direction when throttle pipe is fully rotated to 85 degrees is 36 milliseconds or
less. The Hall Effect IC, gives less response time in clock wise direction, i.e. the movement
24
of throttle-pipe from 85 degrees to 0 degrees position. The output response time of Hall
Effect Sensor IC of is 36 milliseconds (See Figure 10).
Throttle position sensor provides two redundant outputs to increase reliability of throttle
position sensor. In throttle position sensor, two independent outputs are obtained when5
throttle pipe is operated/Output from Die A is 0.5 volts at 0 degree rotation to 4.5 volts at
85 degree rotation of the throttle pipe. And output from Die B is 0.25 volts at 0 degree
rotation to 2.25 volts at 85 degree rotation of the throttle pipe which is exactly half of the
output from Die A. The co-relation between two redundant outputs from Die A and Die B
is accurately maintained.10
25
We Claim:
1. A single piece magnetic field sensor component part comprising a printed circuit
board (12) and a hall effect integrated circuit (IC) (11) having dual hall elements in
single chip (C) integrated in to a physically single piece as a non-contact type dual5
output sensor operating on an independent dual power supply and a single magnet
integrated in a rotor, characterized in that the hall effect IC (11) is soldered directly
on the printed circuit board (12) or integrated as one piece with the printed circuit
board (12) without requirement of an IC holder between the hall effect IC (11) and
the printed circuit board (12).10
2. The single piece magnetic field sensor component part as claimed in claim 1,
wherein the hall effect IC (11) comprises two in-built separately programmable hall
elements, the two hall elements being designated herein as Die A and Die B.
15
3. The single piece magnetic field sensor component part as claimed in claim 1, for
controlling the performance of an engine control unit (ECU) of an automobile via
sensing change in magnetic flux, generated by a relative positional change of the
magnet due to rotation of a throttle of the automobile mounted on its handle bar, by
hall effect sensors to generate two independent output electrical signals which are20
proportional to the magnitude of the relative positional change and these signals are
conveyed to the ECU.
4. The single piece magnetic field sensor component part as claimed in claim 1,
wherein the single piece magnetic field sensor component part comprising the25
printed circuit (12) and the hall effect integrated circuit (IC) (11) integrated in to the
physically single piece by being soldered to a wiring harness, and being fitted in a
lower case by inserting it in a pocket provided in the lower case, covered with a
potting material and wiring harness fitted with a cable tie, a specific gap relation is
maintained between the hall effect IC (11) and the magnet fitted in a rotor.30
5. The single piece magnetic field sensor component part as claimed in claim 1,
wherein one Die of the hall effect IC (11) is programmed to sense the magnetic flux
26
value of the magnet and gives a first output signal (OUT1) with respect to angular
movement of throttle pipe from 0 degree to 85 degrees, which is master output to the
ECU, at the same time the other Die B of hall effect IC (11) is programmed and is
used for giving second output signal (OUT2) with respect to angular movement of
the throttle pipe from 0 degree to 85 degrees for redundancy purpose for serving as a5
diagnostic signal to the ECU; and hall effect IC (11) being programmed with 16 or 6
point calibration method.
6. The single piece magnetic field sensor component part as claimed in claim 1,
wherein10
(a) both the Die A and the Die B operates on an independent +5V power supply
with individual ground connections; whereas the first output signal gives a linear
analog output signal (OUT1) of from 0.5V to 4.5V and whereas the second linear
analog output signal (OUT2) gives an output of from 0.25V to 2.25V and vice
versa when the throttle pipe is rotated in counter-clock-wise and clock-wise15
direction, these two independent analog outputs being achieved by programming
both the Die A and the Die B inside of the hall effect IC (11) through an external
programming device (GUI (graphical user interface tool) which distinguishes first
and second output characteristics by providing and filling adequate parameters in
the GUI to each Die with respect to the magnetic flux density sensed by each Die20
during angular movement of the magnet fitted in the rotor while rotating along with
the throttle pipe, the hall effect IC (11) being an axis position sensor which senses
magnetic flux density of the magnet in lengthwise (X), lateral (Y) and vertical (Z)
direction of the magnet;
b. an analog voltage outputs of each of the two Dies, the Die A and the Die B,25
linearity of a Throttle Position Sensor being maintained within +2% linearity over
its entire operating range;
c. the throttle position sensor construction is designed to fit within a 27-30 mm
range in addition to the length of the throttle pipe;
d. a response time of the throttle position sensor in counter clock wise direction30
when the throttle pipe is fully rotated to 85 degree is 36 milliseconds or less;
i. the hall effect IC (11) gives less response time in clock wise direction,
i.e. the movement of throttle pipe from 85 degrees to 0 degrees position; and
27
ii. the output response time of hall effect IC (11) of is 36 milliseconds;
e. the output from Die A is 0.5 volts at 0 degree rotation to 4.5 volts at 85 degree
rotation of the throttle pipe and output from Die B is 0.25 volts at 0 degree rotation
to 2.25 volts at 85 degree rotation of the throttle pipe which is exactly half of the
output from Die A; the co-relation between two redundant outputs from Die A and5
Die B is accurately maintained;
f. the collective dimensional variation of the throttle pipe, the rotor, the magnet, the
single piece magnetic field sensor component part comprising the printed circuit
(12) and the hall effect IC (11) integrated in to the physically single piece being not
more than +0.40 mm, the magnet width is 1 mm more than hall effect IC (11);10
g. the magnet used in the throttle position sensor has following properties: material:
NdFeB. Arc type, grade : N35, magnetic flux density - with Gauss Value : 1500 +/-
500 gauss, magnetized in such a way that it has a neutral axis formation at the
center of the magnet, and the two arching sides on the two sides of the center of the
magnet have opposite polarities [north (N) and south (S)] on outer and inner15
portion/surface of the arc/arch in such a way that if on one side north pole is on the
upper side and south pole is on the lower side, on the other side, the south pole is
on the upper side and the north pole is on the lower side; and
h. the dimensions of parts of throttle position sensor being maintained in a range of
+0.10 mm.20