The present disclosure relates to the field of transmission systems in vehicles.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
Shifter fork - The term "shifter fork" hereinafter in complete specification refers to a metallic lever with a forked end that slides gears into or out of engagement with other gears to change gear ratios in a manual transmission gearbox.
BACKGROUND
A gearbox of a vehicle is used for transmitting power from an engine to wheels of the vehicle. The gearbox comprises an input shaft that receives power from the engine of the vehicle. The input shaft is coupled to an output shaft of the gearbox via a countershaft. The countershaft is coupled with the input shaft, and receives power therefrom. A plurality of driving gears is mounted on the counter shaft. Each of the driving gears can be engaged with a plurality of driven gears mounted on the output shaft. This gear arrangement facilitates transmission of power from the countershaft to the output shaft. A first driving gear of the plurality of driving gears is connectable to adjacent second driving gear for transmitting the power. The second driving gear is also connectable to a third driving gear. Generally, the connection between the first driving gear and the second driving gear, and between the second driving gear and the third driving gear is facilitated by splines configured on the aforementioned gears. Typically, the splines are configured on both sides of the second gear. However, the provision of splines on both sides of the driving gears reduces the strength of the gears, and increases the probability of spline breakage at higher speeds. Furthermore, there exists a space constraint in the gearbox for arranging the aforementioned gears with the spline arrangement.

Therefore, there is felt a need of a gear arrangement for a transmission in a vehicle that alleviates the abovementioned drawbacks of the conventional gearboxes.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a gear arrangement for a transmission in a vehicle that is compact.
Still another object of the present disclosure is to provide a gear arrangement for a transmission in a vehicle that improves strength of the gears.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a gear arrangement for a transmission in a vehicle. The gear arrangement comprises an input shaft and an output shaft. The input shaft is configured to receive power from an engine of the vehicle. A countershaft is coupled to the input shaft to receive power from the input shaft. The countershaft is defined by a first portion and a second portion. The gear arrangement further comprises a first driving gear, a second driving gear, and a third driving gear. The first driving gear is rotatably mounted on the first portion of the countershaft. The second driving gear is splined-mounted on the first portion of the countershaft, and the third driving gear is splined-mounted on the second portion of the countershaft. An output shaft is disposed parallel to the countershaft, wherein the output shaft is coupled to a transmission member of the vehicle.

A plurality of projections is configured on the first driving gear. Each of the plurality of projections axially projects from the first driving gear. A plurality of slots is configured on the second driving gear. Each of the plurality of slots is configured to receive the plurality of projections of the first driving gear when the second driving gear is axially connected to the first driving gear.
Further, a collar protrudes from the second driving gear, and is configured to connect the second driving gear to the second portion of the countershaft.
In an embodiment, each of the plurality of projections has a shape of dog-tooth, and each of the plurality of slots has a shape complementary to the dog-tooth.
The collar protruding from the second driving gear has internal splines having a shape complementary to external splines configured on the second portion of the countershaft.
The gear arrangement further comprises a shifter fork operatively coupled to a gear lever of the vehicle. The shifter fork is configured to displace the second driving gear towards the first driving gear or towards the second portion of the countershaft.
In an embodiment, the collar configured on the second driving gear has a receiving slot configured to receive the shifter fork.
In an embodiment, the first driving gear is rotatably mounted on the first portion of the countershaft via a bush.
The gear arrangement of the present disclosure further comprises a first driven gear mounted on the output shaft configured to engage with the first driving gear. Further, a second driven gear is mounted on the output shaft, wherein the second driving gear is configured to selectively engage with the second driven gear. Furthermore, a third driven gear is mounted on the output shaft, and is configured to engage with the third driving gear.

In an embodiment, the input shaft, the countershaft, and the output shaft are splined shafts.
In another embodiment, the internal diameter of the collar configured on the second driving gear is more than the internal diameter of a bore of the second driving gear.
In yet another embodiment, the plurality of slots and the collar are configured on opposite sides of the second driving gear.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A gear arrangement for a transmission in a vehicle, of the present disclosure, will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a sectional view of a gear arrangement showing a first position of a second driving gear, in accordance with an embodiment of the present disclosure;
Figure 2 illustrates a sectional view of the gear arrangement of Figure 1 showing a second position of the second driving gear, in accordance with an embodiment of the present disclosure;
Figure 3 illustrates a sectional view of the gear arrangement of Figure 1 showing a third position of the second driving gear, in accordance with an embodiment of the present disclosure;
Figure 4A and Figure 4B illustrates a front view and a cross-sectional view of a first driving gear of the gear arrangement of Figure 1, in accordance with an embodiment of the present disclosure; and
Figure 5 A and Figure 5B illustrates a front view and a cross-sectional view of the second driving gear of the gear arrangement of Figure 1, in accordance with an embodiment of the present disclosure.

LIST OF REFERENCE NUMERALS
100 – Gear arrangement
101 – Gearbox housing
102 – Input shaft
5 104 – Countershaft
106 – First portion
108 – Second portion
110 – First driving gear
112 – Second driving gear
10 114 – Third driving gear
116 – Output shaft
118 – Plurality of projections
120 – Plurality of slots
122 – Collar
15 123 – Receiving slot
124 – Internal splines on the collar
126 – Shifter fork
128 – Bush
130 – First driven gear
20 132 – Second driven gear
6

134 – Third driven gear
136 – Bearings
138 – Drive gear
140 – Driven gear
5 DETAILED DESCRIPTION
The present disclosure envisages a gear arrangement for a transmission in a vehicle that is compact in configuration.
The gear arrangement for the transmission in the vehicle, of the present disclosure, is now described with reference to Figure 1 through Figure 5B.
10 Referring to Figure 1 to Figure 5B, a gear arrangement 100 is disclosed. The gear
arrangement 100 comprises a gearbox housing 101, an input shaft 102, an output shaft 116 and a countershaft 104. The input shaft 102, the countershaft 104 and the output shaft 116 are disposed within the gearbox housing 101. The input shaft 102 is configured to receive power from an engine of the vehicle.
15 Further, the countershaft 104 is coupled to the input shaft 102 to receive power
from the input shaft 102. The input shaft 102 is coupled with the countershaft 104 via a drive gear 138 and a driven gear 140. Typically, the drive gear 138 is integral with the input shaft 102.
The countershaft 104 is coupled to the output shaft 116, and transfers power from
20 the input shaft 102 to the countershaft 104. The output shaft 116 is disposed
parallel to the countershaft 104. Further, the output shaft 116 is coupled to a transmission member of the vehicle. In an embodiment, the input shaft 102, the countershaft 104 and the output shaft 116 are splined shafts.
The countershaft 104 is defined by a first portion 106 and a second portion 108. In
25 an embodiment, a slot (not specifically labelled in figures) is configured on a first
7

end of the second portion 108 of the countershaft 104 to receive the first portion
106 of the countershaft 104. Further, the first end and the second end of the
second portion 108 are supported by the gearbox housing 101 via bearings 136. In
an embodiment, the driven gear 140 is mounted on the first portion 106 of the
5 countershaft 104, and is constantly engaged with the drive gear 138.
Further, the gear arrangement 100 comprises a first driving gear 110. The first
driving gear 110 is rotatably mounted on the first portion 106 of the countershaft
104. In an embodiment, the first driving gear 110 is rotatably mounted on the first
portion 106 via a bush 128. A plurality of projections 118 (as shown in figure 4A
10 and figure 4B) is circumferentially configured on the first driving gear 110. Each
of the plurality of projections 118 is axially projected from the first driving gear 110. In an embodiment, each of the plurality of projections 118 has a shape of dog-tooth with pre-determined dimensions.
The gear arrangement 100 further comprises a second driving gear 112 splined-
15 mounted on the first portion 106 of the countershaft 104. Internal splines are
configured on the bore of the second driving gear 112 to facilitate mounting of the
second driving gear 112 on the countershaft 104.
A plurality of slots 120 (as shown in figure 5A and figure 5B) is circumferentially
configured on one of the sides the second driving gear 112. Each of the plurality
20 of slots 120 of the second driving gear 112 is configured to receive the plurality of
projections 118 of the first driving gear 110, when the second driving gear 112 is axially connected to the first driving gear 110. In an embodiment, each of the plurality of slots 120 has a shape complementary to the dog-tooth configured on the first driving gear 110.
25 Further, a collar 122 is configured on the second driving gear 112 such that the
collar 122 protrudes from the second driving gear 112. The collar 122 is configured to connect the second driving gear 112 to the second portion 108 of the countershaft 104. In an embodiment, the collar 122 has internal splines 124
8

having a shape complementary to external splines (not specifically labelled in
figures) configured on the second portion 108 of the countershaft 104. In another
embodiment, the internal diameter of the collar 122 configured on the second
driving gear 112 is more than the internal diameter of the bore of the second
5 driving gear 112. This facilitates reception of the second portion 108 of the
countershaft 104 by the collar 122.
The gear arrangement 100 further includes a third driving gear 114 that is splined-
mounted on the second portion 108 of the countershaft 104. Typically, the second
driving gear 112 is mounted between the first driving gear 110 and the third
10 driving gear 114.
The plurality of slots 120 and the collar 122 are configured on opposite sides of
the second driving gear 112. More specifically, the plurality of slots 120 is
configured on a side of the second driving gear 112 which faces the first driving
gear 110. The collar 122 is configured on another side of the second driving gear
15 112 which faces the third driving gear 114.
The provision of the collar 122 on only one side of the second driving gear 112
minimizes the space constraints in the gearbox housing 101. Further, the strength
of the second driving gear 112 is improved as splines are configured at only one
side of the second driving gear 112. Further no spline arrangement is provided on
20 the first driving gear 110 and the third driving gear 114. This improves the
strength of the first driving gear 110 and the third driving gear 114.
The gear arrangement 100 further comprising a shifter fork 126 operatively
coupled to a gear lever (not shown in figures) of the vehicle. The shifter fork 126
is coupled to the second driving gear 112, and is configured to displace the second
25 driving gear 112 towards the first driving gear 110 or the second portion 108 of
the countershaft 104. A receiving slot 123 is configured on the collar 122 to securely receive the shifter fork 126.
9

Upon applying force on the gear lever in a predetermined direction, the shifter fork 126 displaces the second driving gear 112 in the axial direction so as to connect the second driving gear 112 to the first driving gear 140 or to the second portion 108 of the countershaft 104.
5 The gear arrangement 100 further comprises a first driven gear 130, a second driven gear 132, and a third driven gear 134 mounted on the output shaft 116. The first driven gear 130 mounted on the output shaft 116 is configured to engage with the first driving gear 110. Further, the second driving gear 112 is configured to selectively engage with the second driven gear 132 mounted on the output shaft 10 116. Furthermore, the third driven gear 134 mounted on the output shaft 116 is configured to engage with the third driving gear 114. More specifically, the first driven gear 130 and the third driven gear 134 are constantly engaged with the first driving gear 110 and the third driving gear 114 respectively.
All the aforementioned gears, i.e., the drive gear 138, the driven gear 140, the first 15 driving gear 110, the second driving gear 112, the third driving gear 114, the first driven gear 130, the second driven gear 132, and the third driven gear 134, can be made of any suitable material. In an embodiment, the aforementioned gears are made of case hardened steel, preferably 20MnCr5 alloy.
Figure 1 illustrates a first position of the second driving gear 112. In the first 20 position, the second driving gear 112 is engaged with the second driven gear 132. The first position can also be termed as “second gear transmission”. The transmission route is as follows.
The engine—► the input shaft 102 —►the drive gear 138 —► the driven gear 140—► the first portion 106 of the countershaft 104 —►the second driving gear 25 112 —►the second driven gear 132 —►the output shaft 116.
Figure 2 illustrates a second position of the second driving gear 112. In the second position, the second driving gear 112 is displaced towards the first driving gear 110 using the gear lever and the shifter fork 126 such that the second driving gear
10

112 is connected to the first driving gear 110. The connection between the second driving gear 112 and the first driving gear 110 is facilitated by the plurality of projections 118 and the plurality of slots 120. The second position can also be termed as “first gear transmission”. The transmission route is as follows.
5 The engine—►the input shaft 102 —►the drive gear 138 —► the driven gear 140—► the first portion 106 of the countershaft 104 —► the second driving gear 112 —►the first driving gear 110 —►the first driven gear 130 —►the output shaft 116.
Figure 3 illustrates a third position of the second driving gear 112. In the third 10 position, the second driving gear 112 is displaced towards the second portion 108 of the countershaft 104 using the gear lever and the shifter fork 126 such that the second driving gear 112 is connected to the second portion 108. The connection between the second driving gear 112 and the second portion 108 is facilitates by the internal splines configured on the collar 122 and the external splines 15 configured on the second portion 108. The third position can also be termed as “third gear transmission”. The transmission route is as follows.
The engine —► the input shaft 102 —►the drive gear 138 —►the driven gear 140—► the first portion 106 of the countershaft 104 —► the second driving gear 112 —► the second portion 108 of the countershaft 104 —►the third driving gear 20 114 —► the third driven gear 134 —►the output shaft 116.
The gear arrangement of the present disclosure reduces the space constraints existing in the conventional gearboxes and further provides a compact gear arrangement. Further, the gear arrangement improves the strength of the gears and reduces chances of spline breakage.
25 The gear arrangement of the present disclosure can be retrofitted in any type of vehicle with appropriate changes.
TECHNICAL ADVANCEMENTS
11

The present disclosure described herein above has several technical advantages including, but not limited to, the realization of a gear arrangement for a transmission in a vehicle:
• that is compact; and
5 • that improves the strength of the gears.
The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof 10 are explained with reference to the non-limiting embodiments 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 15 skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments 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
20 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
25 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.
12

Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation

WE CLAIM

A gear arrangement (100) for a transmission in a vehicle, said gear arrangement (100) comprising:
an input shaft (102) configured to receive power from an engine of said vehicle;
a countershaft (104) coupled to said input shaft (102), and configured to receive power from said input shaft (102), said countershaft defined by a first portion (106) and a second portion (108);
a first driving gear (110) rotatably mounted on said first portion (106) of said countershaft (104);
a second driving gear (112) mounted on said first portion (106) of said countershaft (104);
a third driving gear (114) mounted on said second portion (108) of said countershaft (104);
an output shaft (116) disposed parallel to said countershaft (104), and coupled to a transmission member of said vehicle;
characterized in that,
a plurality of projections (118) is configured on said first driving gear (110), wherein each of said plurality of projections (118) axially projects from said first driving gear (110);
a plurality of slots (120) is configured on said second driving gear (112), wherein each of said plurality of slots (120) is configured to

receive said plurality of projections (118) when said second driving gear (112) is axially connected to said first driving gear (110); and
a collar (122) protrudes from said second driving gear (112), wherein said collar (122) is configured to connect said second driving gear (112) to said second portion (108) of said countershaft (104).
The gear arrangement (100) as claimed in claim 1, wherein each of said plurality of projections (118) has a shape of a dog-tooth, and each of said plurality of slots (120) has a shape complementary to said dog-tooth.
The gear arrangement (100) as claimed in claim 1, wherein said collar
(122) has internal splines (124) having a shape complementary to external
splines configured on said second portion (108) of said countershaft (104).
The gear arrangement (100) as claimed in claim 1, which further comprises a shifter fork (126) operatively coupled to a gear lever of said vehicle, wherein said shifter fork (126) is configured to displace said second driving gear (112) towards said first driving gear (110) or towards said second portion (108) of said countershaft (104).
The gear arrangement (100) as claimed in claim 4, wherein a receiving slot
(123) is configured on said collar (122) to receive said shifter fork (126).
The gear arrangement (100) as claimed in claim 1, wherein said first driving gear (110) is rotatably mounted on said first portion (106) of said countershaft (104) via a bush (128).
The gear arrangement (100) as claimed in claim 1, which comprises:
a first driven gear (130) mounted on said output shaft (116) and configured to engage with said first driving gear (110);

a second driven gear (132) mounted on said output shaft (116), wherein said second driving gear (112) is configured to selectively engage with said second driven gear (132); and
a third driven gear (134) mounted on said output shaft (116) and configured to engage with said third driving gear (114).
The gear arrangement (100) as claimed in claim 1, wherein said input shaft (102), said countershaft (104) and said output shaft (116) are splined shafts.
The gear arrangement (100) as claimed in claim 1, wherein the internal diameter of said collar (122) is more than the internal diameter of a bore of said second driving gear (112).
The gear arrangement (100) as claimed in claim 1, wherein said plurality of slots (120) and said collar (122) are configured on opposite sides of said second driving gear (112).