JP2629924B2 - Transmission transmission - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission for a transmission, and in particular, can prevent gear damping noise during a reverse shift operation, and can reduce wear of a gear chamfer portion. The present invention also relates to a transmission transmission capable of avoiding loss and improving durability.

[Conventional technology]

2. Description of the Related Art A vehicle equipped with a prime mover such as an internal combustion engine is provided with a transmission in order to take out a driving force generated by the prime mover as required according to an operation state. The transmission includes a gear type, a belt type, a type using a fluid coupling, and the like, and a gear type transmission having a small transmission loss of driving force is often used. This gear-type truss transmission usually has a first gear train to a fourth gear train or a first gear train to a fifth gear train as a forward gear train and a reverse gear train as a reverse gear train.

[Problems to be solved by the invention]

By the way, the forward gear train of the truss transmission is provided with a synchronous meshing mechanism in order to quickly and easily perform a shift operation during forward running, but the reverse gear train is provided with a reverse shift operation when the vehicle is stopped. In many cases, a synchronous meshing mechanism is not provided in consideration of the operation. For this reason, during a reverse shift operation, particularly during a quick reverse shift operation immediately after the clutch is disengaged, a gear buffering sound is generated in the reverse gear train, and wear and loss are generated in the gear chamfer portion, resulting in a durability. There was a problem that sex was impaired.

To solve such problems, Japanese Patent Laid-Open No.
No. 156752, Japanese Utility Model Publication No. 56-138255, Japanese Utility Model Application Sho 63-28
There is one disclosed in Japanese Patent Publication No. 946 or the like.

However, all of the publications disclosed in these publications have a disadvantage that the structure is complicated because a means for suppressing friction by applying frictional resistance to a shaft such as a counter shaft of the transmission is provided.

[Object of the invention]

Accordingly, an object of the present invention is to achieve the same effect as the synchronous meshing mechanism with a simple configuration, to prevent gear damping noise at the time of a reverse shift operation, to reduce wear of the gear chamfer part, and to reduce loss. An object of the present invention is to realize a transmission transmission that can be avoided and can improve durability.

[Means for solving the problem]

In order to achieve this object, the present invention provides a fifth-speed reverse shift yoke which is moved in a reverse shift direction during a reverse shift operation of a transmission to move a reverse shift shaft to mesh with a reverse gear train, and to perform the reverse shift operation. A transmission provided with a reverse gear squeeze prevention mechanism for slightly operating a synchronous meshing mechanism provided in a forward gear train of the transmission at an early stage of the reverse shift operation so as to eliminate a relative rotational speed difference between an input shaft and a counter shaft of the transmission. In the transmission, the reverse gear squeak prevention mechanism includes a third-speed / fourth-speed shift shaft hole, a fifth-speed shift shaft hole, and a fifth-speed shift shaft hole of a fifth-speed / reverse-shift yoke of the transmission.
A speed / fourth speed shift shaft, a fifth speed shift shaft, and a reverse shift shaft are slidably fitted and provided. The fifth speed shift shaft is engaged with a fifth speed / reverse shift yoke during a fifth speed shift operation. A fifth speed locking member for moving the fifth speed shift shaft in the fifth speed shift direction is provided, and the reverse shift shaft is engaged with the fifth speed / reverse shift yoke at the time of the reverse shift operation to move the reverse shift shaft in the reverse shift direction. A first engagement hole communicating with the fifth speed shift shaft hole and the reverse shift shaft hole is provided in a fifth speed reverse shift yoke between the fifth speed shift shaft hole and the reverse shift shaft hole. In the first engagement hole, the other end is pressed by the outer peripheral surface of the fifth speed shift shaft during the reverse shift operation, and one end is engaged with the reverse side engagement / disengagement hole of the reverse shift shaft.
At the time of the speed shift operation, a first engagement body, one end of which is pressed by the outer peripheral surface of the reverse shift shaft and the other end is engaged with the fifth speed side engagement / disengagement hole of the fifth speed shift shaft, is slidably inserted and provided, The fifth-speed shift shaft is provided with a second engagement hole in the radial direction, and a fifth-speed side groove is provided on the outer peripheral surface on the side where the other end of the second engagement hole is open so as to be directed in the axial direction. In the neutral position, one end is engaged with the yoke side engaging / disengaging hole of the fifth speed shift shaft hole in the neutral state, and the other end is pulled out from the fifth speed side groove. A second engagement body, which is pressed by the surface and the other end of which projects into the fifth-speed side groove, is slidably fitted and provided, and is provided between the third-speed / fourth-speed shift shaft and the fifth-speed shift shaft hole. The reverse shift yoke communicates with the fifth speed shift shaft hole so that one end faces the fifth speed side groove, and the other end has the third speed. A third engagement hole communicating with the fourth-speed shift shaft hole is provided, and the third-speed / fourth-speed shift shaft is provided with a third-speed / fourth-side groove directed axially to an outer peripheral surface facing the third engagement hole. In the neutral position, one end of the third engagement hole is inserted into a fifth speed side groove extending in the reverse shift direction to abut on the other end of the second engagement body, and the other end is connected to the third speed / fourth speed. During the reverse shift operation, one end is pressed by the other end of the second engagement body, and the other end is pushed into the third-speed / fourth-speed side groove extending in the fifth-speed shift direction, and the other end is retracted from the shift shaft hole. Is characterized in that a third engagement body engaged with the engagement wall surface of the third-speed / fourth-speed side groove extending in the fifth-speed shift direction is slidably fitted and provided.

[Action]

According to the configuration of the present invention, when the reverse gear squeak prevention mechanism starts the reverse shift operation, the fifth speed / reverse shift yoke moved in the reverse shift direction engages with the reverse locking body to reverse the reverse shift shaft. The other end of the first engagement body is disengaged from the fifth speed side engagement / disengagement hole and one end is engaged with the reverse side engagement / disengagement hole, and one end of the second engagement body is engaged with the yoke side engagement hole. The other end is released from the hole and is inserted into the fifth speed side groove extending in the reverse shift direction to press one end of the third engagement body,
3rd speed in which the other end of the third engagement body extends in the 5th speed shift direction.
3 protrudes into the 4th speed groove and extends in the 5th speed shift direction
The third and fourth speed shift shafts are slightly moved in the fourth speed shift direction by being locked on the locking walls of the speed and fourth speed side grooves.

The reverse gear squeak prevention mechanism is arranged such that when the fifth speed / reverse shift yoke is further moved in the reverse shift direction, one end of the third engagement body extends in the reverse shift direction as it passes over the other end of the second engagement body. The other end of the third engagement body is protruded into the speed side groove, is pulled out from the third speed / fourth side groove extending in the fifth speed shift direction, is separated from the locking wall surface, and is engaged with the third speed / fourth speed shift shaft. The movement in the fourth gear shift direction is stopped.

As described above, the reverse gear squeak prevention mechanism is operated in the initial stage of the reverse shift operation, together with the reverse shift shaft, in the 3rd speed / 4th speed.
Move the high speed shift shaft slightly in the 4th speed shift direction,
The input shaft and the counter shaft are connected to each other via the fourth-speed gear train by slightly operating the speed synchronous meshing mechanism, thereby making it possible to eliminate a difference in the relative rotation speed between the input shaft and the counter shaft.

〔Example〕

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

 1 to 6 show an embodiment of the present invention.

In FIG. 1, reference numeral 2 denotes a transmission. The transmission 2 supports an input shaft 6 serving as a rotation shaft and a counter shaft 8 in a case 4. The input shaft 6 and the counter shaft 8 are provided with first to fifth speed gear trains 10 to 18 for forward movement and a reverse gear train 20 for reverse movement.

The first speed gear train 10 includes a main first speed gear 10m and a counter first speed gear 10c. The second gear train 12 includes a main second gear 12m and a counter second gear 12c. 3rd gear train
14 comprises a main third speed gear 14m and a counter third speed gear 14c. The fourth speed gear train 16 includes a main fourth speed gear 16m and a counter fourth speed gear 16c. The fifth speed gear train 18 includes a main fifth speed gear 18m and a counter fifth speed gear 18c. The reverse gear train 20 includes a main reverse gear 20m and a counter reverse gear 20c and a reverse idler gear 20i. The reverse idler gear 20i is connected to the reverse idler gear shaft 22.
It is pivoted on.

Between the first gear train 10 and the second gear train 12, there is a first gear
A two-speed synchronous meshing mechanism 24 is provided. Between the third-speed gear train 14 and the fourth-speed gear train 16, a third-speed / fourth-speed synchronous meshing mechanism 26 is provided. The fifth speed gear train 18 has a fifth speed synchronous meshing mechanism.
28 are provided. Further, the reverse gear train 20 is provided with a reverse meshing mechanism 30.

The transmission 2 switches each of the gear trains 10 to 20 according to running conditions,
A drive wheel (not shown) is driven via 32.

As shown in FIG. 2, a transmission 34 for switching the gear trains 10 to 20 of the transmission 2 uses a shift lever (not shown) to move a shift and select shaft 38 via a control shaft 36 in an axial direction and a circumferential direction. Move. The shift and select shaft 38 is provided with a shift and select protrusion 40. This shift and select protrusion
40 is provided by the axial movement of the shift and select shaft 38.
1-speed / 2-speed shift yoke provided on 1-speed / 2-speed shift shaft 42
44 and a third / fourth speed shift yoke 48 provided on a third / fourth speed shift shaft 46 and a fifth speed / reverse shift yoke 54 provided on a fifth speed shift shaft 50 and a reverse shift shaft 52 are selectively engaged. .

The first speed / second speed shift shaft 42, the third speed / fourth speed shift shaft 46, the fifth speed shift shaft 50, and the reverse shift shaft 52 are provided with a first speed / second speed shift fork 55 and a third speed / fourth speed shift fork, respectively. 56
, A fifth-speed shift fork 58 and a reverse shift arm 60. The first-speed / second-speed shift fork 55
The first-speed / second-speed synchronous meshing mechanism 24 is engaged with the first-speed / second-speed switching sleeve 62. 3-speed / 4-speed shift fork 56
Is engaged with a third-speed / fourth-speed switching sleeve 64 of the third-speed / fourth-speed synchronous meshing mechanism 26. 5-speed shift fork 58
Are engaged with the fifth speed switching sleeve 66 of the fifth speed synchromesh 28. Further, the reverse shift arm 60 is engaged with a reverse sleeve 68 of the reverse meshing mechanism 30. The reverse sleeve 68 is provided on the reverse idler gear 20i.

Thus, the shift-and-select projections 40 are selectively engaged with the first-speed / second-speed shift yoke 44, the third-speed / fourth-speed shift yoke 48, and the fifth-speed / reverse shift yoke 54 by the axial movement of the shift-and-select shaft 38. The first and second speed shift shafts 42 and 3 are moved by the circumferential movement of the shift and select shaft 38.
One of the high speed / fourth speed shift shaft 46, the fifth speed shift shaft 50, and the reverse shift shaft 52 is moved in the axial direction, and the first speed / second speed shift fork 55, the third speed / fourth speed shift fork 56, and the fifth speed A first speed / second speed switching sleeve 62, a third speed / fourth speed switching sleeve 64, a fifth speed switching sleeve 66, and a reverse sleeve 68 via one of the shift fork 58 and the reverse shift arm 60.
The first gear train 10 to the fifth gear train 18 and the reverse gear train 20 are selectively meshed with each other.

In order to eliminate the difference in the relative rotation speed between the input shaft 6 and the counter shaft 8 during the reverse shift operation of the transmission 34 of the transmission 2, the first forward gear train 10 to the fifth forward gear train 18 are provided. 1st speed / 2nd speed synchronous meshing mechanism 24, 3rd speed / 4
For example, the third-speed synchronous meshing mechanism 26 and the fifth-speed synchronous meshing mechanism 28
A reverse gear squeak prevention mechanism 70 for slightly moving the four-speed synchronous meshing mechanism 26 is provided.

The reverse gear squeeze prevention mechanism 70 is, as shown in FIGS. 3 to 6, a third-speed / fourth-speed shift shaft hole in which the third-speed / fourth-speed shift shaft 46 is slidably fitted in the fifth-speed / reverse shift yoke 54. A 5-speed shift shaft hole 74 into which the 72 and 5-speed shift shaft 50 are slidably inserted.
And a reverse shift shaft 76 into which the reverse shift shaft 52 is slidably fitted.

The fifth speed shift shaft 50 has an arrow B at the time of the fifth speed shift operation.
A fifth speed engagement member 78 is provided which engages with the fifth speed / reverse shift yoke 54 moved in the direction. Further, the reverse shift shaft 52 is provided with a reverse locking body 80 that engages with the fifth speed / reverse shift yoke 54 that is moved in the direction of arrow A during the reverse shift operation.

5 between the fifth speed shift shaft 50 and the reverse shift shaft 52
The speed / reverse shift yoke 54 is provided with a first engagement hole 82 communicating with the fifth speed shift shaft hole 74 and the reverse shift shaft hole 76, and a first engagement body 84 is slid into the first engagement hole 82. It is movably fitted and provided. The first engagement body 84 is formed between the inner peripheral surface 74a of the fifth speed shift shaft hole 74 and the inner peripheral surface 7 of the reverse shift shaft hole 76.
It is provided slightly protruding from 6a. One end 84a of the first engagement body 84 is engaged with the outer peripheral surface 52a of the reverse shift shaft 52.
A reverse side engaging hole 86 to be detached is provided. Also, 5
The other end 84b of the first engagement body 84 is provided on the outer peripheral surface 50a of the speed shift shaft 50.
The fifth speed side engagement / disengagement hole 88 is provided for engagement / disengagement.

The fifth speed shift shaft 50 is provided with a second engagement hole 90 in the radial direction, and a second engagement body 92 having substantially the same length as the diameter of the fifth speed shift shaft 50 can slide in the second engagement hole 90. Is provided by being inserted into.
The fifth speed shift shaft hole 74 of the fifth speed / reverse shift yoke 54
The inner peripheral surface 74a is provided with a yoke-side engagement / disengagement hole 94 with which one end 92a of the second engagement body 92 is engaged in a neutral state and is detached during a reverse shift. 5-speed shift shaft
On the outer peripheral surface 50a of the second member 50, the second engaging member 92 is directed in the axial direction.
Is provided with a fifth-speed side groove 96 into which the other end 92b of the second gear enters and withdraws. Sliding slopes 96a and 96b are provided at both ends of the fifth speed side groove 96, respectively.
Is provided.

A fifth speed / reverse shift yoke 54 between the third speed / fourth speed shift shaft 46 and the fifth speed shift shaft 50 communicates with a third speed / fourth speed shift shaft hole 72 and a fifth speed shift shaft hole 74. A third engagement hole 98 is provided, and a third engagement body 100 is slidably fitted into the third engagement hole 98. One end 100a and the other end 100b of the third engagement body 100 are provided so as to be able to protrude and retract from the inner peripheral surface 72a of the third speed / fourth shift shaft hole 72 and the inner peripheral surface 74a of the fifth speed shift shaft hole 74. . One end 100a of the third engagement body 100
Is projected from the inner peripheral surface 74a of the fifth-speed shift shaft hole 74 in the neutral state, and protrudes into the fifth-speed groove 96 of the fifth-speed shift shaft 50,
The second engagement body 92 is in contact with the other end 92b. In addition, the other end 100b of the third engagement body 100 enters and withdraws from the outer peripheral surface 46a of the third-speed / fourth-speed shift shaft 46 in the axial direction.
A fourth speed groove 102 is provided. At both ends of the third-speed / fourth-side groove 102, a sliding slope 102a and a locking wall surface 102b are provided, respectively.

 Next, the operation will be described with reference to FIGS.

In the neutral state of the transmission 2, the transmission
The fifth speed / reverse shift yoke 54 is in the state shown in FIG.

When the fifth speed / reverse shift yoke 54 is started to move in the direction of arrow A by a reverse shift operation to engage the reverse gear train 20, the fifth speed / reverse shift yoke 54 and the reverse locking body 80 are engaged as shown in FIG. The engagement causes the reverse shift shaft 52 to move slightly in the direction of arrow A. With this movement, the other end 84b of the first engagement body 84 is pressed by the outer peripheral surface 50a of the fifth speed shift shaft 50 and moved to the reverse shift shaft 52 side, and one end 84a is engaged with the reverse side engagement / disengagement hole of the reverse shift shaft 52. 8
6 is engaged. Further, the second engagement body 92 has one end 92a pressed by the inner peripheral surface 74a of the fifth speed shift shaft hole 74 and is moved to the third speed / fourth shift shaft 46 side, and the other end 92b of the third engagement body 100 One end 100a is pressed to move the other end 100b of the third engagement body 100 to the third speed / 4
It is made to protrude into the third and fourth speed grooves 102 of the speed shift shaft 46. Thereby, the other end 100b of the third engagement body 100 is locked to the locking wall surface 102b of the third-speed / fourth-speed side groove 102.

For this reason, in the initial stage of the reverse shift operation, the third-speed / fourth-speed shift shaft 46 together with the reverse shift shaft 52 is slightly moved in the direction of the arrow A which is the fourth-speed shift operation direction, and
The fourth speed synchromesh 26 is slightly moved. Therefore, the input shaft 6 and the counter shaft 8 are connected to each other via the fourth speed gear train 16, so that the relative rotation speed difference between the input shaft 6 and the counter shaft 8 can be eliminated.

When the fifth speed / reverse shift yoke 54 is further moved in the direction of arrow A, as shown in FIG. 5, the third engagement body 100 is moved to the fifth speed side groove 96 by the one end 100a riding over the other end 92b of the second engagement body 92. The other end 100b is disengaged from the locking wall surface 102b of the third-speed / fourth-side groove 102 to be urged into
It is withdrawn from the inner peripheral surface 72a of the speed shift shaft hole 72. Accordingly, the third-speed / fourth-speed shift shaft 46 stops moving in the direction of arrow A, which is the fourth-speed shift operation direction, and returns to the neutral position by locating in the direction of arrow B, which is the third-speed shift operation direction. Return.

Further, when the fifth speed / reverse shift yoke 46 is moved in the direction of arrow A, the reverse shift shaft 52 is moved together with the fifth speed / reverse shift yoke 46 as shown in FIG. 6, and the reverse shift operation is completed.

Thus, the reverse gear squeak prevention mechanism 70
At the beginning of the reverse shift operation, the third- and fourth-speed synchronous meshing mechanism 26 provided in the forward third- and fourth-speed gear train 16 of the transmission 2 is slightly operated, and the input shaft 6 and the counter shaft 8 are connected during the reverse shift operation. Eliminating the relative rotational speed difference. In other words, at the time of the reverse shift operation,
The input shaft 6 and the counter shaft 8 are connected via the third-speed / fourth-speed gear train 16 by the operation of the third-speed / fourth-speed synchronous meshing mechanism 26 provided in the fourth-speed gear train 16, so that the input shaft 6 and the counter The relative rotational speed difference with the shaft 8 is eliminated.

For this reason, it is not necessary to provide a means for suppressing rotation by the conventional frictional resistance, so that the structure is simple, the same effect as that of the synchronous meshing mechanism can be obtained, and the gear damping sound at the time of the reverse shift operation can be prevented. Further, the wear of the gear chamfer portion can be reduced and the loss can be avoided, whereby the durability can be improved.

In addition, the 5th speed berth shift yoke 54 allows the 3rd speed
Since the fourth-speed shaft 46, the fifth-speed shift shaft 50, and the reverse shift shaft 52 are held, the rigidity of the shift shaft can be improved.

〔The invention's effect〕

As described above, according to the present invention, the reverse gear squeak prevention mechanism allows the third and fourth speed shift shafts to move slightly in the fourth speed shift direction together with the reverse shift shaft in the initial stage of the reverse shift operation, thereby enabling the third and fourth speed synchronization. By coupling the input shaft and the counter shaft via the fourth-speed gear train by slightly operating the meshing mechanism, it is possible to eliminate the difference in the relative rotation speed between the input shaft and the counter shaft.

For this reason, the same effect as the synchronous meshing mechanism can be obtained with a simple configuration, the occurrence of a gear collision noise at the time of the reverse shift operation can be prevented, the wear of the gear chamfer can be reduced, and the loss can be avoided. As a result, the durability can be improved.

[Brief description of the drawings]

1 to 6 show an embodiment of the present invention. FIG. 1 is a sectional view of a transmission, FIG. 2 is a side view of a transmission, and FIGS. It is. In the figure, 2 is a transmission, 4 is a case, 6
Is an input shaft, 8 is a counter shaft, 10 is a 1st gear train, 12 is a 2nd gear train, 14 is a 3rd gear train, 16 is a 4th gear train, 18 is a 5th gear train, 20 is a reverse gear train, 24 is a first-speed / second-speed synchronous meshing mechanism, 26 is a third-speed / fourth-speed synchronous meshing mechanism, 28 is a fifth-speed synchronous meshing mechanism, 30 is a reverse meshing mechanism, 34 is a transmission, 38 is a shift and select shaft, and 42 is 1st and 2nd speed shift shaft, 44 is 1st and 2nd speed shift yoke, 46 is 3rd and 4th speed shift shaft, 48 is 3rd speed
Speed / fourth speed shift yoke, 50 is a fifth speed shift shaft, 52 is a reverse shift shaft, 54 is a fifth speed / reverse shift yoke, 70 is a reverse gear squeak prevention mechanism, 72 is a third speed / fourth speed shift shaft hole,
74 is the 5th shift shaft hole, 76 is the reverse shift shaft hole, 78 is 5
Fast locking body, 80 is a reverse locking body, 82 is a first engagement hole, 84 is a first engagement body, 86 is a reverse side engaging and disengaging hole, 88 is a fifth speed side engaging and disengaging hole, and 90 is a second engagement. A hole, 92 is a second engaging body, 94 is a yoke side engaging and disengaging hole, 96 is a fifth speed side groove, 98 is a third engaging hole, 100 is a third engaging body, and 102 is a third speed and fourth speed side groove.

Claims (1)

(57) [Claims] A reverse shift shaft is moved by a fifth speed reverse shift yoke which is moved in a reverse shift direction during a reverse shift operation of a transmission to engage a reverse gear train, and an input shaft of the transmission is operated during the reverse shift operation. The transmission transmission device provided with a reverse gear squeak prevention mechanism for slightly operating a synchronous meshing mechanism provided in a forward gear train of the transmission at an early stage of the reverse shift operation so as to eliminate a relative rotational speed difference between the transmission and the counter shaft. The reverse gear squeak prevention mechanism includes a third-speed / fourth-speed shift shaft, a fifth-speed shift shaft, a fifth-speed shift shaft, a fifth-speed shift shaft, a fifth-speed shift shaft, and a fifth-speed shift shaft. A reverse shift shaft is slidably fitted and provided. At the time of the fifth speed shift operation, a fifth speed locking member is provided which engages with the fifth speed / reverse shift yoke to move the fifth speed shift shaft in the fifth speed shift direction. A reverse locking member is provided for engaging the reverse shift yoke and moving the reverse shift shaft in the reverse shift direction. The fifth speed reverse shift yoke between the fifth speed shift shaft hole and the reverse shift shaft hole has a fifth speed shift shaft. A first engagement hole communicating with the shift shaft hole and the reverse shift shaft hole is provided, and the other end is pressed by the outer peripheral surface of the fifth speed shift shaft during the reverse shift operation so that one end is reverse-shifted. The fifth engagement portion is engaged with the reverse side engagement / disengagement hole of the shaft, one end of which is pressed by the outer peripheral surface of the reverse shift shaft during the fifth speed shift operation, and the other end is engaged with the fifth speed side engagement / disengagement hole of the fifth speed shift shaft. 1 The 5th speed shift shaft is provided with a second engagement hole in the radial direction, and the second engagement hole is axially directed to the outer peripheral surface on the side where the other end of the second engagement hole is opened. A fifth speed side groove is provided, and one end of the second engagement hole is engaged with the yoke side engagement / disengagement hole of the fifth speed shift shaft hole in the neutral state, and the other end is pulled out of the fifth speed side groove and the reverse shift is performed. At the time of operation, a second engagement body, one end of which is pressed by the inner peripheral surface of the fifth speed shift shaft hole and the other end of which is inserted into the fifth speed side groove, is slidably fitted and provided.
The fifth speed / reverse shift yoke between the fourth speed shift shaft and the fifth speed shift shaft hole is connected to the fifth speed shift shaft hole such that one end faces the fifth speed side groove, and the other end is shifted to the third speed / fourth speed shift hole. A third engagement hole communicating with the shaft hole is provided, and a third-speed / fourth-speed side groove is provided in the third-speed / fourth-speed shift shaft so as to be directed in the axial direction on an outer peripheral surface facing the third engagement hole; In the neutral state, one end of the third engagement hole is inserted into a fifth speed side groove extending in the reverse shift direction and abuts on the other end of the second engagement body, and the other end is a third speed / fourth speed shaft hole. And at the time of a reverse shift operation, one end is pressed by the other end of the second engagement body, and the other end is inserted into a third-speed / fourth-speed groove extending in the fifth-speed shift direction, and the other end is engaged with a fifth-speed gear. The third engagement body engaged with the engagement wall surface of the third-speed / fourth-side groove extending in the shift direction is slidably fitted. Transmission of the transmission, characterized in that digit.