[001] The present subject matter described herein, relates to a manual speed transmission for a vehicle, and particularly to a six-speed manual transmission system with input shaft braking for reverse gear shifting. More particularly, the present reverse gear braking system use one of the forward gear synchronizer to apply brake on input shaft of manual transmission gear system.
BACKGROUND AND PRIOR ART:
[002] In the six-speed manual transmission system, reverse gear arm is provided separately with yoke to actuate the reverse gearing of the vehicle.
[003] Generally, in manual transmissions, vehicle operator moves stick which is connected to a gear shift lever to change gears in gearbox via gear shift mechanism. The gearbox comprises an input shaft and an output shaft which are interlinked with each other through gears. The input shaft has plurality of forward gear sets which engaged with gears of output shaft to drive the vehicle. Further, the gearbox has a reverse idler assembly for engaging the vehicle in reverse gear. Generally, the reverse idler assembly has a reverse input gear driven by the input shaft, a reverse output gear driven by the output shaft, and a reverse idler gear which is selectively movable into meshed engagement with the reverse input gear and the reverse output gear for driving the output shaft in a second direction. The reverse idler gear is a gear used to change the direction of the rotation of the shafts.
[004] During operation of the vehicle, operator presses clutch to shift the reverse gear from neutral position. Pressing clutch disconnect Engine and Input shaft and the input shaft rotates freely due to inertia. In this situation, if the vehicle operator moves the gear (stick) in reverse gear position to shift the reverse gear mode while the input shaft is still rotating, teeth of the reverse gear idler meshes with the teeth of the reverse input gear and reverse idler gear starts rotating. Wherein teeth of the rotating reverse gear idler get clashed with the teeth of the rotating output shaft

and create clattering noise due to speed different between two gears. This condition is generally known as "reverse clash" which results in unpleasant noise and clashing/vibrations are felt by the vehicle operator.
[005] In one option to avoid this situation, the vehicle operator either has to wait till the time when input shaft stops rotating or brake is applied on the inputs shaft to reduce the speed of the input shaft. The first option consumes lot of time and irritates the vehicle operator. Further, there is another way to avoid this reverse clashing is to stop the rotation of the input shaft before an attempt is to made to put the vehicle in reverse gear. There are several techniques which removes the reverse clash in the gear box.
[006] Existing solution provide system for applying brake on the input shaft via forward gears using synchronizer attached to forks of the forward gear. The existing system is complex and uses more number of parts to apply brake on the input shaft.
[007] Though existing solutions reduces the reverse clash as they are intended for, but each has its own drawbacks and limitations. These known systems are costly and have several special parts which are very complex. This complexity makes the serviceability of the system difficult and costly. Therefore, a simple and inexpensive reverse gear shifting system is required which is effective to eliminate reverse gear clash while shifting the gear shift lever from forward gear to reverse gear.
OBJECTS OF THE INVENTION:
[008] The principal objective of the present invention is to provide six speed gear manual transmission with reverse gear braking system.
[009] Another object of the present invention is to provide a reverse gear arm with ball and spring mechanism to move the forward shift gear having synchronizer to apply brakes.
[0010] Another object of the present subject matter is to use 3rd and 4th gear synchronizer ring for stopping the rotation of input shaft.

[0011] Another object of the present invention is to provide simple structure to eliminate reverse clash in the gearbox.
[0012] Yet another object of the present invention is to provide low cost system for reduction of noise in the gearbox while reverse gearing.
SUMMARY OF THE INVENTION:
[0013] This summary is provided to introduce concepts related to a manual speed transmission system for applying brakes on rotating input shaft unit forwarding gears. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0014] The present subject matter relates to a manual gear transmission system for applying brakes on rotating input shaft of gearbox during shifting of reverse gear. The manual gear transmission comprises a plurality of gear shift rails connected with corresponding gear shift yoke to provide shift motion upon actuation by a lever gear shift select (LGSS) and a plurality of forks coupled with synchronizer rings is connected with the plurality of gear shift rails to change gears in the gearbox. Further, the manual speed transmission system has a reverse gear arm having idler gear actuator arm and a gear shift yoke arm extending axially along the gear shift rail direction. The reverse gear arm is slidably mounted on the gear shift rail through hole and on the other gear shift rail through a hole. Further, a ball and spring mechanism provided in the reverse gear arm that engages with the gear shift rail to push third and fourth gear synchronizer mounted on the shift rail to apply brake on the rotating input shaft.
[0015] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0016] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0017] Fig. la, lb, and lc illustrate structure of six speed manual gear transmission system, in accordance with an embodiment of the present subject matter;
[0018] Fig. 2a-2c illustrate structure of reverse gear shift arm with ball and spring mechanism, in accordance with an embodiment of the present subject matter;
[0019] Fig. 3a and 3b illustrate structure of shift shaft, circlips, ball spring mechanism, and interlock plate, in accordance with embodiment of the present subject;
[0020] Fig. 4a-4d illustrate reverse gear engagement as per structure of gear system as shown in figure 1, in accordance with embodiment of the present subject;
[0021] Fig. 5a-5c illustrate reverse gear dis-engagement as per structure of gear system as shown in figure 1, in accordance with embodiment of the present subject; and
[0022] Fig. 6a-6c illustrate third and fourth gear engagement in the present manual gear transmission system, in accordance with embodiment of the present subject.

[0023] The figures depict embodiments of the present subject matter for the
purposes of illustration only. A person skilled in the art will easily recognize from
the following description that alternative embodiments of the structures and
methods illustrated herein may be employed without departing from the principles
5 of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0024] The detailed description of various exemplary embodiments of the
disclosure is described herein with reference to the accompanying drawings. It
should be noted that the embodiments are described herein in such details as to
10 clearly communicate the disclosure. However, the amount of details provided
herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
15 [0025] It is also to be understood that various arrangements may be devised that,
although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
20 [0026] The terminology used herein is for the purpose of describing particular
embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or
25 “including,” when used herein, specify the presence of stated features, integers,
steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
6

[0027] It should also be noted that in some alternative implementations, the
functions/acts noted may occur out of the order noted in the figures. For example,
two figures shown in succession may, in fact, be executed concurrently or may
sometimes be executed in the reverse order, depending upon the functionality/acts
5 involved.
[0028] Unless otherwise defined, all terms (including technical and scientific
terms) used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which example embodiments belong. It will be further
understood that terms, e.g., those defined in commonly used dictionaries, should
10 be interpreted as having a meaning that is consistent with their meaning in the
context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0029] Embodiments explained herein pertain to a six-speed manual transmission system having a plurality of gear shift rails for shifting various gears, such as
15 First, second, third, fourth, fifth, six and reverse gear. The present system prevent
generation of reverse clash noise and make shifting of reverse gear smooth. Regardless of their specific construction, a perspective view of the six speed manual transmission system 100 is shown in figures 1 and 2. The conventional manual transmission system has various components or parts which increases cost
20 and complexity of the system. Further, some existing system are available for
single shift rail not for multiple shift rail. However, their implementation is complex and includes a plurality of components. Therefore, implementation of the existing system in the multiple shift rail would be quite different and prone to errors thereby leading to increase in cost and serviceability.
25 [0030] To this, the present disclosure provides a six-speed manual transmission
system having a plurality of shift rails as shown in figure 1, 2, and 3.
[0031] As shown in the figures, arrow Y indicates upward direction, arrow X indicates axial or longitudinal direction and arrow Z indicates forward direction.
[0032] FIG. 1a-1c illustrates structure of the manual gear transmission system as per
30 present subject matter. These figures show shifting mechanism or shift shafts and not
7

gear transmission arrangement. As shown in the figure, the present manual
transmission system 100 is six speed gear manual transmission system in which
reverse gear can be placed after the high gears, such as fifth and six gear or before
the low gears, such as first and second gear. In the present construction or
5 arrangement, the reverse gear selection and shifting is placed after the fifth and six
gear selection and shifting pattern. The present manual transmission system 100 includes a plurality of gear shift rails 101, 102, 103, input shaft (not shown), output shaft (not shown), a plurality of forks 101x, 102x, 103x mounted on corresponding gear shift rails. The plurality of forks 101x, 102x, 103x are parts
10 that move on the shifting of gear and actually moves the component to change the
gears inside the gearbox. For example, for six speed transmission, there are three gear shift rails. One gear shift rail forward and backward to select the two possibilities of the gear. For example, first shift rail 103 is moved forward and backward to select first and second gear. Similarly, second shift rail 102 is moved
15 to select third and fourth gear, and third shift rail 101 is moved to select fifth and
six gear. Further, a synchronizer sleeve is connected with the forks 101x, 102x, 103x. The synchronizer sleeve receives the input from the forks and moves forward and backward as per input to the gear shift rail.
[0033] As shown in figures 1a-1c, a reverse gear arm 108 is freely slidable over 5th
20 and 6th gear shift rail 101 and slidable over third and fourth gear shift rail 102. For
ease of assembly and transportation of parts reverse gear arm 108 with the gear shift rail 101 and the gear shift rail 102, a circlip 109 is provided on the gear shift rail 101 and the gear shift rail 102 at end opposite to yoke.
[0034] As shown in figure 2a-2c, structure of the reverse gear arm 108 is illustrated.
25 The reverse gear arm 108 has idler gear actuator arm 108a and a reverse gear shift
yoke arm 104. The idler gear actuator arm 108a extend in downward direction ‘Y’ and coupled with the reverse gear. The reverse gear shift yoke arm 104 extend axially along the gear shift rail 101 in direction X to positioned with other yokes 104, 105, 106 of gear shift rail 101, the gear shift rail 102, and the gear shift rail
30 103, respectively. The yoke 104 of the reverse gear shift yoke arm 104 is at top
8

position to select and shift reverse gear in the six speed manual transmission system 100.
[0035] The reverse gear arm 108 has two mounting holes 108d, 108e in axial
direction X to co-axially mount with the shift rail 101 and the gear shift rail 102,
5 respectively. The reverse gear arm 108 is slidably mounted on the gear shift rail
101 through the hole 108e and on the gear shift rail 102 through the hole 108d. Another cylindrical slot 108g is provided on the reverse gear arm 108 in direction Y. One end of the cylindrical slot 108g is a top and other end matches with or opens in the mounting hole 108d.
10 [0036] As shown in figure 2a and 2b, the reverse gear arm 108 has a ball and
spring mechanism having ball 108c and spring 108b (collectively can be referred as a ball and spring mechanism 108b, 108c). One end of the spring 108b is connected with the ball 108c and other end is restricted by a pin 108a. The pin 108a provided through a pin hole 108f in the cylindrical slot 108g to cover top
15 end of the spring 108b and allow up and down movement of the ball 108c at other
end. The ball and spring mechanism 108b, 108c is provided in the cylindrical slot 108g where a portion of the ball 108c emerges out in the mounting hole 108d.
[0037] Referring to figure 3a, the gear shift rail 102 has a plurality of curved slots
102a, 102b, 102c to receive the emerged portion of the ball 108c of the ball and
20 spring mechanism 108b, 108c in the mounting hole 108d. The ball 108c remains
in curved slot 102b during neutral gear position.
[0038] Referring to figure 3b illustrating structure of the ball and spring
mechanism 108b, 108c that can be inserted in the reverse gear arm 108 from the
cylindrical slot 108g. Further, the circlips 109 are provided to prevent dis-
25 assembly of the reverse gear arm 108 with the gear shift rail 101 and gear shift rail
102.
[0039] Figure 4a illustrates structure of interlock plate 110 that is another important embodiment of the present subject matter. As shown in the figure 4a, the interlock plate 110 is positioned with yokes position to allow movement of
9

requested yoke and prevent movement of other yokes for shifting the gears. The
interlock plate 110 has an upper arm 110a and lower arm 110b. The lower arm
110b having a depth portion 110d (notch portion) after a protruding portion 110c.
The depth portion 110d allows movement of 3rd and 4th gear rail upto partial
5 engagement with the inputs shaft.
[0040] Further figures illustrate working of the gears according to present disclose
manual speed transmission system. Fig. 4a-4d illustrate engagement of the reverse
gear by stopping movement of the input shaft with the help of the third gear
synchronizer. Fig. 4a illustrate view of manual transmission system in neutral
10 position. In the neutral position, the LGSS 111 is in middle yoke arrangement and the
ball 108c of the ball and spring mechanism 108b, 108c engages with middle curved slot 102b.
[0041] Referring to figure 4b where the LGSS 111 moves the yoke 104 of the reverse gear arm 108 to engage the reverse gear. As indicated by arrow 113a the reverse gear
15 arm 108 slides over the gear shift rail 101 in right side direction and as indicated by
arrow 114 the reverse gear arm 108 slides over the plurality of curved slots 102a, 102b through the ball and spring mechanism 108b, 108c. Due to spring force, in the ball and spring mechanism 108b, 108c engagement with the plurality of curved slots 102a, 102b, 102c forces the gear shift rail 102 to engage fourth gear synchronizer ring
20 with the input shaft. The lower arm 110b of the interlock plate 110 prevent movement
of other gear yokes. The depth portion 110d allows limited movement of 3rd and 4th gear shift shaft/rail 102. The ball and spring mechanism 108b, 108c inside the reverse gear arm 108 moves along with the 3rd and 4th shift rail 102 till the gear shift rail 102 is stopped by the depth portion 110d of the interlock plate 110. During further stroke
25 of the reverse gear arm 108 the ball 108c climbs in groove/curved slot 101a.
Accordingly, the spring 108b receive the compression force. As the movement of the gear shift rail 102 as indicated by arrow 114 is limited by the depth ‘d’ of the depth portion 110d. The depth portion 110d is sized to permit the partial engage of gear means engagement of synchronizer ring teeth not teeth of the fourth gear dog with the
30 input shaft. Accordingly, the synchronizer ring applies brakes on the input shaft.
10

[0042] Figure 4c illustrates full engagement of the reverse gear. As shown in the
figure, the movement of the gear shift rail 102 is stopped by the interlock plate 110
beyond a defined limit. After stop, the ball 108c climbs over the curved slot of the
gear shift rail 102 until the reverse gear engagement is complete. After completion of
5 reverser gear engagement, the gear shift rail 102 start returning to its neutral position
due to spring force on the ball 108c and the curved slots 102a, 102b as indicated by arrow 115, 116, 117.
[0043] Fig. 4d illustrate neutral position of the gear shift rail 102 after reverse gear
engagement. As indicated by the arrow 118, the gear shift rail 102 returns to neutral
10 position by the spring force. However, the ball 108c engaged with the curved slot
102a of the gear shift rail 102.
[0044] Figure 5a-5c illustrates reverse gear dis-engagement. As shown in the figure
5a and 5b, arrow 119, 120, 121 indicate leftward movement of the reverse gear arm
yoke 104 by the LGSS 111 while movement of the gear shift rail 102 of the 3rd and 4th
15 gear is stopped by other face of the lower arm 110b that is opposite to the depth
portion 110d of the interlock plate 110. The ball 108c starts climbing over the curved slot 102a due to load on the reverse yoke 104. The ball 108c climb over the curved clot 102a and rests in the curved slot 102b of original neutral position as shown in figure 5c as indicated by arrow 122, 123, 124, 125.
20 [0045] Figure 6a-6c illustrate 3rd and 4th gear engagement with the present manual
transmission system 100. Figure 6a illustrate neutral position where selection of 3rd or 4th gear is to be taken. As shown in the figure, the ball 108c is engagement with the curved slot 102b of the gear shift rail 102. Arrow 126 indicates leftward movement of the LGSS 111 to shift the third gear. As shown in the figure 6b and indicated by
25 arrow 127, the LGSS 111 moves leftward direction to shift the third gear. During
shifting of third gear, the reverse gear arm 108, 5-6th gear or shift rail 101 and 1st-2nd gear or shift rail 103 is fixed by the interlock plate 110. The ball 108c of the ball spring mechanism 108b, 108c is engaged with the curved slot 102a of the gear shift rail 102 as the gear shift rail 102 moves in leftward direction with respect to
30 stationary reverser gear arm 108.
11

[0046] Similarly, as shown in figure 6c and indicated by arrow 128, the LGSS 111
moves the yoke 106 of the 3rd-4th gear in rightward direction indicated by arrow 128.
During shifting of fourth gear, the reverse gear arm 108, 5-6th gear or shift rail 101
and 1st-2nd gear or shift rail 103 is fixed by the interlock plate 110. The ball 108c of
5 the ball spring mechanism 108b, 108c is engaged with the curved slot 102c of the
gear shift rail 102 as the gear shift rail 102 moves in rightward direction with respect to stationary reverser gear arm 108.
[0047] 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
10 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
15 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
20 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
25 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
30 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
12

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 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."
[0048] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

We claim:

A manual gear transmission system (100) for applying brakes on rotating input shaft of gearbox during shifting of reverse gear, the manual gear transmission system (100) comprises:
a plurality of gear shift rails (101, 102, 103) connected with corresponding gear shift yoke (105, 106, 107) to provide shift motion upon actuation by a lever gear shift select (LGSS) (111);
a plurality of forks (lOlx, 102x, 103x) coupled with synchronizers is connected with the plurality of gear shift rails (101, 102, 103) to change gears in the gearbox;
characterized in that
a reverse gear arm (108) having idler gear actuator arm (108) and a gear shift yoke arm (104) extending axially along the gear shift rail (101) direction,
the reverse gear arm (108) slidably mounted on the gear shift rail (101) through hole (108e) and on the gear shift rail (102) through a hole (108d),
a ball and spring mechanism (108b, 108c) provided in the reverse gear arm (108) that engages with the gear shift rail (102) to push third and fourth gear synchronizer mounted on the gear shift rail (102) to apply brake on the rotating input shaft.
The manual gear transmission system (100) as claimed in claim 1, wherein the gear shift rail (102) has a plurality of curved slots (102a, 102b, 102c) to receive a portion of ball (108c) of the ball and spring mechanism (108b, 108c).
The manual gear transmission system (100) as claimed in claim 1, wherein the reverse gear arm (108) has cylindrical slot (108g) in vertical direction

(Y) to receive the ball and spring mechanism (108b, 108c) from top end and spring (108b) is restricted by a pin (108a) at the top end.
The manual gear transmission system (100) as claimed in claim 3, wherein other end of the cylindrical slot (108g) having the ball (108c) of the ball and spring mechanism (108b, 108c) opens in the hole (108d) that is slidably coupled with the gear shift rail (102).
The manual gear transmission system (100) as claimed in claim 1, wherein a interlock plate (110) is positioned with the yokes (104, 105, 106, 107) to prevent movement of more than one yoke at a time.
The manual gear transmission system (100) as claimed in claim 5, wherein the interlock plate (110) having upper arm (110a) and lower arm (110b), the lower arm (110b) having a protruded portion (110c) at top to restrict movement of 5th and 6th gear shift rail (101) during shifting of the reverse gear yoke (104) and depth portion (HOd) allows limited (d) movement of the third and fourth gear synchronizer ring of the gear shift rail (102) to partial engage with the rotating input shaft and apply brakes.
The manual gear transmission system (100) as claimed in claim 1, wherein the ball and spring mechanism (108b, 108c) applies back force on the plurality of curved slots (102a, 102b, 102c) of the gear shift rail (102) to keep the gear shift rail (102) in neutral position during shifting of the reverse gear when interlock plate (110) stops movement of the gear shift rail (102) after limited (d) axial movement.
The manual gear transmission system (100) as claimed in claim 1, wherein the gear shift rail (101) and the gear shift rail (102) carries a circlip (109) to preventing dis-assembly of the reverse gear shift arm (108).

The manual gear transmission system (100) as claimed in claim 1, wherein manual gear transmission system (100) is six speed manual transmission with a plurality of shift rails.