Description:TECHNICAL FIELD
[001] The embodiments herein generally relate to transmission shift mechanism in vehicles and more, particularly to a range transmission shift mechanism for a vehicle, which allows a single range shift rail to mount a plurality of range shift forks thereon to facilitate shifting of range gears within a compact packaging space.
BACKGROUND
[002] Generally, a range transmission unit is used for multiplying the number of speeds of a speed transmission unit of an off-road vehicle such as a tractor. The range transmission unit includes a range shift mechanism for manually selecting the respective range gears. Typically, the range shift mechanism includes a range shift lever, one or more range shift rails, range shift forks and range shift couplers (range shift sleeves). In some vehicles, the range transmission unit includes a high range gear and a low range gear which are mounted on separate shafts which are parallel to each other. For this configuration of the range transmission unit, the range shift mechanism includes separate range shift fork mounted onto corresponding separate range shift rail. This results in high cost and consumes more packaging space due to usage of more number of shifting components and increases an overall weight and length of the vehicle.
[003] In other vehicles, the range transmission unit includes the high range gear and the low range gear which are mounted on separate shafts which are co-axial to each other. For this configuration of the range transmission unit, the range shift mechanism includes a single range shift fork mounted onto a single range shift rail which is moved by the range shift lever for selecting the low range gear or the high range gear. Configuration of the vehicle requires the high range gear and the low range gear to be mounted onto separate shafts which are parallel to each other, and further there is a constraint with respect to cost, weight and packaging space in the vehicle, then using a single range shift rail with separate range shift forks for actuating the high range gear or the low range gear may be problematic due to space constraint.
[004] Therefore, there exists a need for a range transmission shift mechanism for a vehicle, which obviates the aforementioned drawbacks.
OBJECTS
[005] The principal object of embodiments herein is to provide a range transmission shift mechanism for a vehicle.
[006] Another object of embodiments herein is to provide the range transmission shift mechanism which is inexpensive and consumes less packaging space.
[007] Another object of embodiments herein is to provide the range transmission shift mechanism which reduces overall weight and length of the vehicle.
[008] These and other objects of embodiments herein will be better appreciated and understood when considered in conjunction with following description and 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 DRAWINGS
[009] The embodiments are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0010] Fig. 1 depicts an exploded view of a range transmission shift mechanism for a vehicle, according to embodiments as disclosed herein;
[0011] Fig. 2 illustrates the range transmission shift mechanism in a high range gear position, according to embodiments as disclosed herein;
[0012] Fig. 3 illustrates the range transmission shift mechanism in a neutral range position, according to embodiments as disclosed herein;
[0013] Fig. 4 illustrates the range transmission shift mechanism in a low range gear position, according to embodiments as disclosed herein;
[0014] Fig. 5 illustrates an inline shift pattern of a range shift lever of the range transmission shift mechanism, according to embodiments as disclosed herein;
[0015] Fig. 6 illustrates the range transmission shift mechanism in the neutral range position, according to embodiments as disclosed herein;
[0016] Fig. 7 illustrates the range transmission shift mechanism in the high range position, according to embodiments as disclosed herein; and
[0017] Fig. 8 illustrates the range transmission shift mechanism in the low range position, according to embodiments as disclosed herein.
DETAILED DESCRIPTION
[0018] 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.
[0019] The embodiments herein achieve a range transmission shift mechanism for a vehicle, which allows a single range shift rail to mount a plurality of range shift forks thereon to facilitate shifting of range gears within a compact packaging space. Further, embodiments herein achieve the range transmission shift mechanism which is inexpensive and consumes less packaging space. Referring now to the drawings Figs. 1 through 8, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0020] Fig. 1 depicts an exploded view of a range transmission shift mechanism (100) for a vehicle, according to embodiments as disclosed herein. Fig. 2 illustrates the range transmission shift mechanism (100) in a high range gear position (H), according to embodiments as disclosed herein. In an embodiment, the range transmission shift mechanism (100) includes a range shift lever (102), a range lever coupler (103), a range shift rail (104), a low range coupler (105), a low range shift fork (106), a high range shift coupler (107), a high range shift fork (108), a spring (110), a ball (112) and a stopper (114). For the purpose of this description and ease of understanding, the range transmission shift mechanism (100) is explained herein with below reference to shifting and selection of a low range gear (30) and a high range gear (20) in an agricultural vehicle such as a tractor with compact packaging space for the transmission. However, it is also within the scope of the invention to use/practice the range transmission shift mechanism (100) in any other agricultural machines or any other off-road vehicles or any other vehicles, where shifting and selection range gears in compact packaging space for the transmission is required, without otherwise deterring the intended function of the range transmission shift mechanism (100) as can be deduced from the description and corresponding drawings.
[0021] The range shift lever (102) is adapted to be moved by the operator of the vehicle for selecting the low range gear (30) or the high range gear (20). The range shift lever (102) is coupled to the range shift rail (104) through the range lever coupler (103). The range shift lever (102) is configured to be operated in an inline shift pattern (H -N- L) (as shown in fig. 5). The range shift rail (104) is adapted to be moved by the range shift lever (102) to facilitate shifting of the low range shift fork (106) and the high range shift fork (108).
[0022] The low range shift fork (106) is mounted onto the range shift rail (104). For example, the low range shift fork (106) is mounted onto the range shift rail (104) through the roll pin (105). The high range shift fork (108) is movably mounted onto the range shift rail (104) and a transmission housing (10) (as shown in figs. 6 to 8). The high range shift fork (108) is positioned near to the low range shift fork (106). The low range shift fork (106) is adapted to move the high range shift fork (108) to a high range gear position (H) in which the high range shift coupler (107) is engaged with a high range gear (20) (as shown in fig. 2) when the range shift lever (102) is moved to the high range gear position (H). The high range shift fork (108) includes an oblong slot (108S) (as shown in fig. 1) adapted to receive one end of the stopper (114).
[0023] The spring (110) is adapted to be received inside a spring receiving portion (10S) (as shown in fig. 6) defined in the transmission housing (10). The ball (112) is adapted to be engaged with one end of the spring (110). The ball (112) is adapted to be loaded against a ball receiving portion (108G, 104G) (as shown in figs. 6 & 7) defined on the high range shift fork (108) and the range shift rail (104) by the spring (110) when the range shift lever (102) is moved to the neutral range position (N). For the purpose of this description and ease of understanding, the ball receiving portion (108G) of the high range shift fork (108) is considered to be a hole, and the ball receiving portion (104G) of the range shift rail (104) is considered to be a groove. The ball (112) disengages from the ball receiving portion (104G) and rests on an elongated groove (104R) (as shown in figs. 7 and 8) defined in the range shift rail (104) when the low range shift fork (106) is moved to the low range position (L). One end of the elongated groove (104R) adjoins the ball receiving portion (104G).
[0024] The ball (112) disengages from the ball receiving portion (108G, 104G) and rests on the high range shift fork (108) in vicinity of the ball receiving portion (108G) when the range shift lever (102) is moved to the high range position (H).
[0025] The stopper (114) is adapted to engage the high range shift fork (108) thereby restricting a movement of the high range shift fork (108) when the low range shift fork (106) is moved to a low range gear position (L) in which the low range coupler (105) is engaged with a low range gear (30) (as shown in fig. 4) when the range shift lever (102) is moved to the low range gear position (L). The stopper (114) is adapted to engage a first end (108X) (as shown in fig. 2) of the oblong slot (108S) thereby restricting a movement of the high range shift fork (108) when the range shift lever (102) is moved from the neutral range position (N) to the low range gear position (L). The stopper (114) is adapted to engage a second end (108Y) (as shown in fig. 3) of the oblong slot (108S) thereby restricting the movement of the high range shift fork (108) beyond predefined position (high range gear engaged position) when the range shift lever (102) is moved to the high range gear position (H). For the purpose of this description and ease of understanding, the stopper (114) is considered to be a pin. It is also within the scope of the invention to use any other elements for restricting the movement of the high range shift fork (108) beyond predefined positions without otherwise deterring the intended function of the stopper (114) as can be deduced from the description and corresponding drawings.
[0026] The technical advantage of the range transmission shift mechanism (100) are as follows. The range transmission shift mechanism is inexpensive and consumes less packaging space. The range transmission shift mechanism reduces overall weight and length of the vehicle.
[0027] 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 embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modifications within the spirit and scope of the embodiments as described herein.
, Claims:We claim:
1. A range transmission shift mechanism (100) for a vehicle, said range transmission shift mechanism (100) comprising:
a low range shift fork (106) mounted onto a range shift rail (104); and
a high range shift fork (108) movably mounted onto said range shift rail (104) and a transmission housing (10), wherein high range shift fork (108) is positioned near to said low range shift fork (106),
wherein
said low range shift fork (106) is adapted to move said high range shift fork (108) to a high range gear position (H) in which a high range shift coupler (107) is engaged with a high range gear (20) when a range shift lever (102) is moved to said high range gear position (H).
2. The range transmission shift mechanism (100) as claimed in claim 1, wherein said range transmission shift mechanism (100) includes,
a spring (110) adapted to be received inside a spring receiving portion (10S) defined in said transmission housing (10); and
a ball (112) adapted to be engaged with one end of said spring (110), wherein
said ball (112) is adapted to be loaded against a ball receiving portion (108G, 104G) defined on said high range shift fork (108) and said range shift rail (104) by said spring (110) when said range shift lever (102) is in a neutral range position (N).
3. The range transmission shift mechanism (100) as claimed in claim 2, wherein said ball (112) is adapted to disengage from said ball receiving portion (108G, 104G) and rests on said high range shift fork (108) in vicinity of said ball receiving portion (108G) when said range shift lever (102) is moved to said high range position (H).

4. The range transmission shift mechanism (100) as claimed in claim 3, wherein said range transmission shift mechanism (100) includes a stopper (114) adapted to engage said high range shift fork (108) thereby restricting a movement of said high range shift fork (108) when said low range shift fork (106) is moved to a low range gear position (L) in which a low range coupler (105) is engaged with a low range gear (30) when said range shift lever (102) is moved to said low range gear position (L).
5. The range transmission shift mechanism (100) as claimed in claim 4, wherein said high range shift fork (108) includes an oblong slot (108S) adapted to receive one end of said stopper (114),
wherein
said stopper (114) is adapted to engage a first end (108X) of said oblong slot (108S) thereby restricting a movement of said high range shift fork (108) when said range shift lever (102) is moved from said neutral range position (N) to said low range gear position (L); and
said stopper (114) is adapted to engage a second end (108Y) of said oblong slot (108S) thereby restricting the movement of said high range shift fork (108) beyond predefined position (high range gear engaged position) when said range shift lever (102) is moved to said high range gear position (H).
6. The range transmission shift mechanism (100) as claimed in claim 5, wherein said stopper (114) is a pin.
7. The range transmission shift mechanism (100) as claimed in claim 2, wherein said ball receiving portion (108G) of said high range shift fork (108) is a hole; and
said ball receiving portion (104G) of said range shift rail (104) is a groove.
8. The range transmission shift mechanism (100) as claimed in claim 2, wherein said low range shift fork (106) is mounted onto said range shift rail (104) through a roll pin (105); and
said range shift lever (102) is coupled to said range shift rail (104) through a range lever coupler (103).
9. The range transmission shift mechanism (100) as claimed in claim 1, wherein said range shift lever (102) is configured to be operated in an inline shift pattern (H -N- L).
10. The range transmission shift mechanism (100) as claimed in claim 4, wherein said ball (112) is adapted to disengage from said ball receiving portion (104G) and rests on an elongated groove (104R) defined in said range shift rail (104) when said low range shift fork (106) is moved to said low range position (L); and
one end of said elongated groove (104R) adjoins said ball receiving portion (104G).