FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10 and rule 13]
“A PEDAL ASSEMBLY AND A METHOD OF ASSEMBLING THEREOF”
NAME AND ADDRESS OF THE APPLICANT:
TATA MOTORS LIMITED, an Indian company having its registered office at Bombay House, 24 Homi Mody Street, Hutatma Chowk, Mumbai 400 001, Maharashtra, INDIA.
Nationality: Indian
The following specification particularly describes the invention and the manner in which it is to be performed.
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TECHNICAL FIELD
The present disclosure is related to a mechanical clutch pedal assembly for a motor vehicle. The disclosure more particularly relates to the design of the clutch pedal assembly to reduce the pedal effort during clutch disengagement.
BACKGROUND OF THE DISCLOSURE
The clutch pedal effort during disengagement and engagement are the crucial parameters in any clutch system and are the important/sensitive customer touch points in all vehicles having manual transmission. These touch points become more critical in mechanical clutch pedal actuation system where clutch cable is used as a medium to transfer the pedal input to clutch.
Conventional clutch cover has only diaphragm spring, which is the source for the release load. This in turn will be reflecting on the clutch pedal in terms of pedal effort.
Actuation of the clutch can be classified into two different types of system. First type of clutch actuation mechanism is a Preload system. In this system the Clutch Releasing Bearing (CRB) is constantly in contact with the clutch cover diaphragm fingers, under predefined preload. The preload is maintained by the pedal return spring in the pedal box, exerting force on the pedal lever and thereby on the cable in pulling it to press the CRB against the clutch cover finger tips. This type is used for higher diameter clutch wherein the release load is higher. The second type of clutch actuation mechanism is a Free play system. In this system the CRB has some clearance with the clutch diaphragm fingers. Also, here the pedal always tries to release the cable in free condition and the pedal tries to move upwards i.e. away from the floor of the vehicle and is stopped by means of stopper on the pedal bracket. There will be at least 1 to 2 more springs on the clutch housing side in this system. The free play system is used for smaller diameter clutch wherein the preload system cannot be used as it will reduce the Factor of safety.
In case of smaller size clutches the pedal return-ability becomes a concern because of lower release load. When free play system is used with smaller clutches,
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though the pedal return is maintained at acceptable limit, the forward pedal effort increases because of different springs used for maintaining free play, pedal return etc.
Thus, there exists a need to develop a pedal assembly to overcome the above said drawbacks.
STATEMENT OF THE DISCLOSURE
Accordingly, the present disclosure provides a pedal arm assembly comprising, a pedal having a hole at predetermined location mounted to a pedal mounting bracket of a vehicle, an arm pivotably connected to the pedal by a pin at one end and is having a provision to support a cable holder on the other end and a stopping means on the pedal to limit the movement of the arm, it also provides a method of assembling a pedal, wherein the method comprises acts of, mounting a pedal having a hole at predetermined location to a pedal mounting bracket, connecting an arm pivotably to the pedal by a pin at one end, wherein the arm is having a provision to support a cable holder on the other end and providing a stopping means on the pedal to limit the movement of the arm.
SUMMARY OF THE DISCLOSURE
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of innovated pedal assembly as described in disclosure.
Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.
Accordingly the present disclosure provides a pedal arm assembly comprising, a pedal having a hole at predetermined location mounted to a pedal mounting bracket of a vehicle. And an arm pivotably connected to the pedal by a pin at one end and is having a provision to support a cable holder on the other end. Further, a stopping element on the pedal is configured to limit the movement of the arm.
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In one embodiment of the disclosure, the cable holder is a u-shaped bracket with a second pin on one end and is having a provision to hold a cable on the other end.
In one embodiment of the disclosure, the stopping means is a u-shaped section on the pedal which restricts the motion of the arm.
In one embodiment of the disclosure, the arm makes an angular displacement in clockwise direction for predetermined distance.
In one embodiment of the disclosure, the arm comprises a cut portion with a through hole drilled on its side faces to pivotably connect with the pedal.
Another embodiment of the disclosure provides a method of assembling a pedal, wherein the method comprises acts of, mounting a pedal having a hole at predetermined location to a pedal mounting bracket. And connecting an arm pivotably to the pedal by a pin at one end, wherein the arm is having a provision to support a cable holder on the other end and providing a stopping means on the pedal to limit the movement of the arm.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The novel features and characteristic of the disclosure are set forth in the appended claims. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
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Fig. 1 illustrates the schematic diagram of clutch pedal assembly according to disclosure.
Figs. 2 and 4 illustrate the schematic diagram of clutch pedal in top engaged position and is held by means of clutch cable.
Fig. 3 illustrates the exploded view of the pedal assembly.
Fig. 5 illustrates the schematic diagram of the pedal position wherein arm is displaced from its initial position (resting towards left) to vertical position.
Fig. 6 illustrates the schematic diagram of the pedal position wherein arm is resting towards its right.
Fig. 7 illustrates the graphical representation of the improved performance of the pedal assembly.
Figs 8a and 8b illustrates the schematic diagram of different cable holders and connectors.
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAIL DESCRIPTION
The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and
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scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.
It is to be noted at this point that all of the above described components, whether alone or in any combination, are claimed as being essential to the disclosure, in particular the details depicted in the drawings and reference numerals in the drawings are as given below.
Referral Numerals
Description
1
Pedal
1a and 1b
Stopping means
2
Arm
3
First Pin
4
Cable holder
5
Mounting bracket
6
U-shaped cut section on pedal
7
Cut section on arm
8
Provision on arm
9
U-shaped Bracket
10
Second pin
11
Provision for holding cable
12
Cable
13
Foot rest
14
Pivot point
7
The present disclosure is related to a mechanical clutch pedal assembly for a motor vehicle. The disclosure more particularly relates to the design of the clutch pedal assembly to reduce the pedal effort during clutch disengagement.
The present disclosure consists of a clutch pedal (1) which is mounted to a mounting bracket (5) of an automobile/vehicle. The pedal (1) comprises of a u-shaped cut section (6) on its top surface for accommodating an arm (2) and bottom surface of the pedal (1) consists of a foot rest (13). The foot rest (13) is located at point “C”. The pedal (1) comprises holes at predetermined locations of which the hole on the right top surface is referred as “O”. Further the assembly consists of the arm (2) which comprises a cut section (7) at its bottom surface to connect with the pedal (1). And further the cut section (7) is drilled on its side surfaces to form holes to receive a first pin (3). The arm (2) is pivotably connected to the pedal (1) at one end by passing the first pin (3) through the holes drilled on the cut section (7) and the pedal (1). Position at which the arm (2) is pivoted to pedal (1) is defined by point “B” which is referred as the pivot point (14). The other end of the arm (2) comprises a provision (8) for supporting a cable holder (4). The provision (8) made in the arm (2) according to the disclosure is a semi-circular groove. A person skilled in art may infer that the provision provided can be of any shape, for eg. Circular, elliptical, etc. The cable holder (4) resting on the arm (2) consists of a u-shaped bracket (9). The u-shaped bracket (9) consists of a second pin (10) at one end and the other side of the u-shaped bracket (9) consists of a provision (11) for holding a cable (12). The cable (12) is attached with the cable holder (4) at point “A” as shown in figs. 1and 2. The arm (2) pivoted to pedal (1) is free to rotate in clockwise direction about first pin (3) to a predetermined distance.
Fig. 3 illustrates the exploded view of the pedal assembly. The pedal assembly as disclosed in the present disclosure comprises a pedal (1) which is mounted to a mounting bracket (2) of the vehicle. The pedal (1) comprises a u-shaped cut section (6) on its top surface to accommodate an arm (2). Also, a plurality of holes is drilled on the pedal (1) at its top end, wherein one of the holes is displaced beneath the said u-shaped cut section (6). Further the arm (2) consists of a cut section (7) at its bottom which is drilled on its side surfaces so that it can accommodate a first pin (3). The first pin (3) pivotably
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connects the arm (2) with the pedal (1). Further, the arm (2) comprises a provision (8) for holding a cable holder (4). The cable holder (4) is a u-shaped bracket (5) with a second pin (10) on one end. The arm (2) supports the second pin (10) in such a manner that arm (2) is free to move within the u-shaped bracket (9). The cable holder (4) on the other side consists of a provision (11) for holding a cable (12).
Fig. 4 describes the initial position of the pedal (1) showing the arm (2) resting towards its left position. In the initial position of pedal (1), arm (2) is inclined towards its left and it rest on the stopping means (1a) of the pedal (1) as shown in fig 4. When the pedal (1) travels in the forward direction to disengage the clutch, the arm (2) starts moving and comes to vertical position as shown in figure 5. In this position projection of length r1 on horizontal axis (distance between O and A) will be equal to projection of length r2 on horizontal axis (distance between O and B). When the projection of length r2 on horizontal axis becomes greater than the projection of length r1 on horizontal axis, the arm (2) rotates in clockwise direction. In this position, the arm (2) will rest toward its right side on stopping means (1b) as shown in figure 6. In this position, lever ratio of the pedal (1) increases. Thus, reducing the pedal effort, this is mainly influenced by lever ratio of the pedal (1).
The present disclosure maintains the clutch pedal lever ratio low initially. The lever ratio for the pedal (1) depends upon length between point OA i.e. r1 and length between OC i.e R. In the present disclosure the length r1 is variable because of rotation of the arm (2). This change of length can be optimized, if the rotation of the arm (2) start before pedal effort reaches its maximum value. Aforesaid optimization is achieved with the help of the pedal assembly as disclosed in the present disclosure, which reduces the pedal effort. Thus the present disclosure provides an increased lever ratio by which the pedal effort is reduced. If Ø & ψ are the respective angle between horizontal axis & OA and horizontal axis & OB then the condition for the arm (2) to rotate clockwise direction is:
(OA)CosØ < (OB) Cosψ
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i.e. (projection of length r1 on horizontal axis) < (projection of length r2 on horizontal axis).
Fig. 7 illustrates the graphical representation of the pedal travel distance versus lever ratio, and pedal effort with constant lever ratio versus pedal effort with variable lever ratio. For given set of parameters (for eg. Pedal ratio, arm rotation angle, release lever ratio and release bearing load of clutch) the pedal assembly is been subjected to performance test and the results have been illustrated in the graphical representation. In graph-1 point wherein both the lines cross each other is the point where the pedal effort reduces. And in graph-2 it is evident that increase in the lever ratio results in reduction of pedal effort.
In an alternative embodiment, the assembly may also be provided with any means for holding cable. The cable holder in the pedal assembly can be a connector assembled with any form of cable having an end cap. For example the cable end cap may be a soldered, round peened, casted, square caulked, ball caulked end cap. And the connector can be of type A and type B as shown in Fig. 8a and 8b. A person skilled in art can infer that any shaped holder can serve the purpose of holding the cable in the disclosed invention.
The foregoing description provides specific embodiments of the present disclosure. It should be appreciated that these embodiment are described for purpose of illustration only, and that numerous other alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.
Equivalents
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
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It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B
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together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
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We claim:
1. A pedal assembly comprising;
a pedal (1) having a hole at predetermined location mounted to a pedal mounting bracket (5) of a vehicle;
an arm (2) pivotably connected to the pedal (1) by a first pin (3) at one end and having a provision (8) to support a cable holder (4) on the other end; and
a stopping means (1a and 1b) on the pedal (1) to limit the movement of the arm (2).
2. The pedal assembly as claimed in claim 1, wherein the cable holder (4) is a u-shaped bracket (5) with a second pin (10) on one end and having a provision (11) to hold a cable (12) on the other end.
3. The pedal assembly as claimed in claim 1, wherein the stopping means (1a and 1b) is a u-shaped section on the pedal (1) which restricts the motion of the arm (2).
4. The pedal assembly as claimed in claim 1, wherein the arm (2) makes an angular displacement in clockwise direction for predetermined distance.
5. The pedal assembly as claimed in claim 1, wherein the arm (2) comprises a cut portion (7) with a through hole drilled on its side faces to pivotably connect with the pedal (1).
6. A method of assembling a pedal, wherein the method comprises acts of:
mounting a pedal (1) having a hole at predetermined location to a pedal mounting bracket (5);
connecting an arm (2) pivotably to the pedal (1) by a first pin (3) at one end; wherein the arm (2) is having a provision (8) to support a cable holder (4) on the other end; and
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providing a stopping (1a and 1b) means on the pedal (1) to limit the movement of the arm (2).