DESC:FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules, 2005

COMPLETE SPECIFICATION
(SEE SECTION 10 AND RULE 13)

TITLE OF THE INVENTION

“SYSTEM FOR DETERMINING POSITION OF A THROTTLE PEDAL IN A VEHICLE”

APPLICANTS:
Name Nationality Address
Mahindra & Mahindra Limited Indian Mahindra Research Valley, Mahindra World, City Plot No. 41/1, Anjur P.O. Chengalpattu, Kancheepuram Dist, Tamilnadu.- 603204

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:-

TECHNICAL FIELD
[001] The embodiments herein generally relate to systems for determining throttle pedal position in vehicles, and more particularly but not exclusively to systems for determining throttle pedal position in vehicles using throttle position sensor.

BACKGROUND
[001] Generally in vehicles, throttle position sensor is one kind of sensor which is used to determine the throttle pedal or accelerator pedal position. The throttle position sensor senses the position of the throttle pedal and provides input to the control unit, based on which various factors like air fuel mixing ratio, exhaust gas recirculation are controlled.
[002] In the contact type throttle position sensor, the sensor gets input from the accelerator or throttle pedal. The throttle position sensor receives input from the throttle pedal of the fuel injection pump through mechanical linkages based on four bar or six bar mechanism. Due to the back clash or end play between the linkages in the conventional four bar or six bar mechanism, the throttle position sensor doesn’t receive proper input and therefore the accuracy and functioning of the throttle position sensor is affected which leads to flow fluctuation in exhaust gas recirculation ultimately leading to more emissions.
[003] Further, the contact type throttle position sensor is programmed to operate at a lower band due to the limitations of the conventional mechanical linkages. Furthermore, the throttle position sensor produces low intensity output signal to control unit, due to lower operating band of the throttle position sensor.
[004] Therefore, there exists a need for an efficient and accurate system for determining position of a throttle pedal in a vehicle. Furthermore, there exists a need for a system that can eliminate the aforementioned drawbacks.

OBJECTS
[005] The principle object of an embodiment of this invention is to provide an efficient and accurate system for determining position of a throttle pedal in a vehicle.
[006] Another object of an embodiment of this invention is to provide a system that permits higher operating band of the throttle position sensor.
[007] Yet, another object of an embodiment of this invention is to provide a system that enables simple home position or zero position setting of the throttle position sensor.
[008] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF FIGURES
[009] The embodiments of this invention is illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0010] FIG. 1 depicts a perspective view of the system according to an embodiment of the invention as disclosed herein;
[0011] FIG. 2 depicts an exploded view of the system without the throttle position sensor according to an embodiment of the invention as disclosed herein;
[0012] FIG. 3 depicts an assembled view of the system in a vehicle according to an embodiment of the invention as disclosed herein; and
[0013] FIG. 4 depicts a perspective view of the drive shaft of the system according to an embodiment of the invention as disclosed herein.

DETAILED DESCRIPTION
[0014] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0015] The embodiments herein achieve an efficient and accurate system for determining position of a throttle pedal in a vehicle. Referring now to the drawings, and more particularly to FIGS. 1 through 4, where similar reference characters denote corresponding features consistently throughout the figures, there are shown preferred embodiments.
[0016] FIG. 1 depicts a perspective view of the system according to an embodiment of the invention as disclosed herein. FIG. 2 depicts an exploded view of the system without the throttle position sensor according to an embodiment of the invention as disclosed herein.
[0017] The system 100 includes a bracket 102, a control rack 104, a drive shaft 106, a gear 108, a sensor holder 110, a guide pin 112, a positioning nut 114, a cover 116, a sensor 118 and a control unit (not shown).
[0018] In an embodiment the bracket 102 includes a first end 102a and a second end 102b. The second end 102b of the bracket 102 is assembled with the cover 116. The first end 102a of the bracket 102 is mounted to any required/appropriate place in the vehicle 400. The bracket 102 is used for holding the system 100. In an embodiment the bracket 102 includes openings (not shown) at the first end 102a and second end 102b for facilitating the mounting of the bracket 102 with the vehicle 400 and the cover 116 using fasteners like bolt, screws etc. However, it is also within the scope of the invention to mount the bracket 102 with the vehicle 400 and the cover 116 using adhesives, welding, riveting etc., or any other means without otherwise deterring the intended function of the bracket 102 as can be deduced from the description. The bracket 102 further includes an opening 102c for receiving the guide pin 112 and an opening 102d for receiving the drive shaft 106.
[0019] In an embodiment, the control rack 104 includes a slot 104a, a plurality of gear teeth 104b, an opening 104c. The slot 104a is used for receiving the guide pin 112. The slot 104a allows the linear movement of the control rack 104. The control rack 104 engages with the gear 108. The gear teeth 104b are used for providing motion to the gear 108. The control rack 104 receives motion from the throttle pedal (not shown). The opening 104c is used for receiving a fastener like bolt or screw (not shown) for operatively connecting the control rack 104 with the throttle pedal (not shown). The control rack 104 is used for transmitting the motion from the throttle pedal (not shown) to the gear 108, thereby driving (rotating) the drive shaft 106 i.e the control rack 104 drives (rotates) the drive shaft 106 through the gear 108. In an embodiment the number of gear teeth 104b in the control rack 104 is predetermined based on the length of travel and radius of the throttle pedal (not shown).
[0020] FIG. 4 depicts a perspective view of the drive shaft of the system according to an embodiment of the invention as disclosed herein. In an embodiment the drive shaft 106 includes a first end 106a and a second end 106b. The drive shaft 106 is configured to receive the gear 108. In an embodiment the drive shaft 106 is assembled with the gear 108 through press or interference fit. By assembling the drive shaft 106 and the gear 108 using interference fit any axial play between the gear 108 and drive shaft 106 is eliminated. The drive shaft 106 is rotatably connected to the sensor 118 through the first end 106a of the drive shaft 106. The second end 106b of the drive shaft 106 is received by the positioning nut 114. The drive shaft 106 is used for providing input to the sensor 118.
[0021] In an embodiment the gear 108 includes a plurality of gear teeth 108a and an opening 108b. The opening 108b is used for mounting the gear 108 with the drive shaft 106. The gear teeth 108a is adapted to mesh with the gear teeth 104b of the control rack 104 to receive motion from the control rack 104. The gear 108 is used for driving (rotating) the drive shaft 106. In an embodiment to allow the sensor 118 to operate at a higher band or maximum degree of rotation the radius of the gear 108 must be less than the radius of the throttle pedal (not shown). Since the radius of the gear 108 is less than the radius of the throttle pedal (not shown) even any slight movement in the control rack 104 due to movement of the throttle pedal (not shown) is amplified by the gear 108 thereby a high intensity output signal is produced by the sensor 118 which leads to better control unit (not shown) performance. Thus the radius of the gear 108 is inversely proportional to output provided by the sensor 118.
[0022] In an embodiment the sensor holder 110 includes an opening 110a for receiving the drive shaft 106. The sensor holder 110 is used for holding the sensor 118 and for protecting the drive shaft 106, gear 108 from dust, mud or any foreign particles. The sensor holder 110 includes openings (not shown) for receiving screws (not shown) for mounting the sensor 200. Further, the sensor holder 110 includes openings (not shown) for receiving screws (not shown) for mounting the cover 116.
[0023] In an embodiment the guide pin 112 is used for preventing the control rack 104 from breaking contact with the gear 108, thereby ensuring the engagement between control rack 104 and gear 108 while eliminating back clash. The guide pin 112 is received by the slot 104a of the control rack 104 and the opening 102c of the bracket 102. In an embodiment the guide pin 112 is a bolt having variable diameter. However it is also within the scope of the invention to provide a standard bolt as guide pin 112 without otherwise deterring the intended function of the guide pin 112 as can be deduced from the description.
[0024] In an embodiment the positioning nut 114 is received by the second end 106b of the drive shaft 106. The positioning nut 114 is used for setting the home position or zero position of the sensor 118. The positioning nut 114 is assembled to the drive shaft 106 outside the cover 116. In an embodiment the positioning nut 114 is assembled to the drive shaft 106 using screw threads (not shown) in the positing nut 114 and in the second end 106b of the drive shaft 106. However it is also within the scope of the invention to assemble the positioning nut 114 with the drive shaft 106 through press or interference fit. As the positioning nut 114 is provided outside the cover 116, the home position setting of the sensor 118 can be made offline or before assembling the system 100 with the vehicle 400. It is also within the scope of the invention to provide the second end 106b of the drive shaft with an integrated positioning nut 114. Further, it is also within the scope of the invention to provide the system 100 without the positioning nut 114 so that the home position setting of the sensor 118 can be made by adjusting the drive shaft 106 directly through the second end 106b of the drive shaft 106.
[0025] In an embodiment the cover 116 includes an opening 116a for receiving the drive shaft 106. The cover 116 is used for protecting the gear 108 and drive shaft 106 from mud, dust, water and other foreign particles. The cover 116 includes openings (not shown) for receiving screws (not shown) for assembling the cover 116 with the sensor holder 110 and the bracket 102.
[0026] In an embodiment the sensor 118 is used for measuring the degree of rotation of the drive shaft 106. The sensor 118 is provided in communication with the control unit (not shown). The sensor 118, based on the degree of rotation of drive shaft 106 accordingly provides the information to the control unit (not shown) to determine the position of the throttle pedal (not shown). However, it is also within the scope of the invention to provide the sensor 118 with an inbuilt processing unit to determine the position of the throttle pedal based on the degree of rotation of the drive shaft 106.
[0027] In an embodiment the control unit (not shown) is used for determining the position of the throttle pedal (not shown). The control unit is provided in communication with the sensor 118 to receive information from the sensor 118 about the degree of rotation of the drive shaft 106 to determine the position of the throttle pedal (not shown).
[0028] FIG. 3 depicts an assembled view of the system in a vehicle according to an embodiment of the invention as disclosed herein. The working of the system 100 is as follows.
[0029] In an, embodiment the first end 102a of the bracket 102 is mounted to the intake manifold mounting stud (not shown). The throttle pedal (not shown) is operatively connected to the control rack 104 through the opening 104c. When the throttle pedal or accelerator pedal is pressed/engaged, motion is transmitted from the throttle pedal (not shown) to the control rack 104. The amount of motion transmitted is based on the degree of rotation of the throttle pedal (not shown). As the control rack 104 is provided with motion, the gear teeth of the control rack 104b meshes with the gear teeth 108a of the gear 108 and the gear 108 is driven or rotated. Since the drive shaft 106 is coupled with the gear 108, the drive shaft 106 rotates with the gear 108 thereby actuating the sensor 118, since the drive shaft 106 is rotatably connected to the sensor 118. The sensor 118 measures the degree of rotation of the drive shaft 106 and accordingly provides information to control unit (not shown) to determine position of said throttle pedal. Thus a system 100 for determining a position of a throttle pedal in a vehicle is provided.
[0030] In an embodiment the sensor 118 has a maximum operating band or degree of rotation of 110 degree. However it is also within the scope of the invention to provide the throttle position sensor having any degree of rotation without otherwise deterring the intended function of the sensor 118 as can be deduced from the description. In an embodiment the radius of the gear 108 is configured to be 2.6 times lesser than the radius of the throttle pedal (not shown). In an embodiment the gear ratio between the control rack 104 and the gear 108 is 1: 2.6. i.e for one revolution of control rack 104 the gear 108 is rotated by 2.6 times. However it is also within the scope of the invention to provide any other value of gear ratio without otherwise deterring the intended function of the system 100 as can be deduced from the description.
[0031] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

CLAIMS
We claim,
1. A system for determining position of a throttle pedal, said system comprising:
a control rack having a plurality of gear teeth;
a gear having a plurality of gear teeth, wherein said plurality of gear teeth of said gear are adapted to engage with said plurality of gear teeth of said control rack; and
a drive shaft connected to said gear;
a sensor adapted to measure the degree of rotation of said drive shaft; and
a control unit adapted to determine the position of said throttle pedal, said control unit provided in communication with said sensor,
wherein
said drive shaft is rotatably connected to said sensor; said control rack is operatively connected to said throttle pedal and said control rack rotatably drives said drive shaft through said gear upon engagement of said throttle pedal; and based on degree of rotation of said drive shaft, said sensor accordingly provides information to said control unit to determine the position of said throttle pedal.
2. The system as claimed in claim 1, further comprising a bracket adapted to mount said system to a vehicle.
3. The system as claimed in claim 1, further comprising a sensor holder adapted to hold said sensor.
4. The system as claimed in claim 1, further comprising a cover adapted to protect said gear and said drive shaft.
5. The system as claimed in claim 1, further comprising a positioning nut adapted to set home position of said sensor.
6. The system as claimed in claim 1, further comprising a guide pin adapted to prevent said control rack from breaking contact with said gear to ensure engagement between said control rack and gear.
7. The system as claimed in claim 1, wherein said control rack comprises a slot adapted to receive said guide pin and said slot facilitates the movement of said control rack.
8. The system as claimed in claim 5, wherein said positioning nut is connected to said drive shaft.
9. The system as claimed in claim 1, wherein the gear ratio between said control rack and said gear is 1: 2.6.
10. The system as claimed in claim 1, wherein radius of said gear is less than radius of said throttle pedal.
11. The system as claimed in claim 10, wherein radius of said gear is 2.6 times lesser than radius of said throttle lever.
12. The system as claimed in claim 1, wherein said sensor is a contact type throttle position sensor.
13. The system as claimed in claim 1, wherein the number of said plurality of gear teeth in said control rack is predetermined based on the length of travel and radius of said throttle pedal.

Dated this 24th November 2015

Signatures:
Name of the Signatory: Dr. Kalyan Chakravarthy

ABSTRACT
System for determining position of a throttle pedal in a vehicle includes a sensor, a control rack, a gear, a drive shaft and a control unit. The control rack is operatively connected to the throttle pedal and the control rack drives the drive shaft through the gear upon engagement of the throttle pedal and based on degree of rotation of the drive shaft, the sensor accordingly provides information to the control unit to determine the position of the throttle pedal.
Fig. 1

,CLAIMS:CLAIMS
We claim,
1. A system for determining position of a throttle pedal, said system comprising:
a control rack having a plurality of gear teeth;
a gear having a plurality of gear teeth, wherein said plurality of gear teeth of said gear are adapted to engage with said plurality of gear teeth of said control rack; and
a drive shaft connected to said gear;
a sensor adapted to measure the degree of rotation of said drive shaft; and
a control unit adapted to determine the position of said throttle pedal, said control unit provided in communication with said sensor,
wherein
said drive shaft is rotatably connected to said sensor; said control rack is operatively connected to said throttle pedal and said control rack rotatably drives said drive shaft through said gear upon engagement of said throttle pedal; and based on degree of rotation of said drive shaft, said sensor accordingly provides information to said control unit to determine the position of said throttle pedal.
2. The system as claimed in claim 1, further comprising a bracket adapted to mount said system to a vehicle.
3. The system as claimed in claim 1, further comprising a sensor holder adapted to hold said sensor.
4. The system as claimed in claim 1, further comprising a cover adapted to protect said gear and said drive shaft.
5. The system as claimed in claim 1, further comprising a positioning nut adapted to set home position of said sensor.
6. The system as claimed in claim 1, further comprising a guide pin adapted to prevent said control rack from breaking contact with said gear to ensure engagement between said control rack and gear.
7. The system as claimed in claim 1, wherein said control rack comprises a slot adapted to receive said guide pin and said slot facilitates the movement of said control rack.
8. The system as claimed in claim 5, wherein said positioning nut is connected to said drive shaft.
9. The system as claimed in claim 1, wherein the gear ratio between said control rack and said gear is 1: 2.6.
10. The system as claimed in claim 1, wherein radius of said gear is less than radius of said throttle pedal.
11. The system as claimed in claim 10, wherein radius of said gear is 2.6 times lesser than radius of said throttle lever.
12. The system as claimed in claim 1, wherein said sensor is a contact type throttle position sensor.
13. The system as claimed in claim 1, wherein the number of said plurality of gear teeth in said control rack is predetermined based on the length of travel and radius of said throttle pedal.