JPH10103432A - Transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission which requires no separate brake mechanism for reverse speed change, has a simple configuration, and is easily manufactured. SOLUTION: A freely rotating drum 13 which has cam channels 14 for change on its peripheral surface, and a speed change shaft 58 which operates with cam channels 14 of the drum 13 to drive a synchromesh speed change mechanism of the transmission 3 are placed close to a transmission 3. The cam channels 14 for change of the rotating drum 13 is for operating the speed change shaft 58 so that during reverse speed change the change mechanism for 1-5 changes in the synchromesh speed change mechanism stops a main shaft 72 using its synchronous action of rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission, and more particularly, to a transmission for shifting a vehicle such as an automobile.

[0002]

2. Description of the Related Art Generally, in a vehicle such as an automobile, a transmission for transmitting a driving force of a driving engine by appropriately setting a rotation speed of a wheel such as a tire with respect to a rotation speed of a driving engine such as an engine. The device is used.

In such a conventional transmission, a plurality of gears at a plurality of speeds are provided around a main shaft which is rotationally driven by a driving engine and an outer periphery of a counter shaft arranged in parallel with the main shaft. A synchromesh transmission mechanism is provided in the gear portion of the step.

By operating a shift fork by operating a shift operation lever, the synchromesh transmission mechanism is operated to engage a gear at a desired speed to perform a desired shift. .

The shift operation lever is generally provided as a floor-type shift operation lever located between a driver's seat and a passenger's seat of a vehicle. Thus, a desired speed change fork is operated via the link mechanism.

In recent years, a vehicle called a walk-through, which can be easily moved by walking from a driver's seat or a passenger seat to a rear seat, has been developed.
In such a vehicle, a walk-through cannot be performed if the floor-type shift operation lever as described above is present. Therefore, the shift operation is usually performed by a column-type shift operation lever provided on a steering column. I do it.

[0007]

However, in the conventional transmission, the rotational force of the driving engine is transmitted via the main shaft and the counter shaft during normal forward running, and the main shaft is transmitted during reverse driving. Is transmitted via the reverse shaft and the counter shaft to rotate the counter shaft in the reverse direction. When shifting from forward to reverse, if the main shaft is rotating, the reverse gear of the main shaft and the gear provided on the reverse shaft cannot be properly engaged with each other. Because biting noise is generated,
Conventionally, a brake mechanism for stopping the rotation of the main shaft during the reverse shift has been provided. As a result, a separate brake mechanism for reverse shifting is required, increasing the number of parts and complicating the structure.
There is a problem that manufacturing is difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is an object of the present invention to provide a transmission that can be easily manufactured with a simple structure without the necessity of separately providing a reverse speed brake mechanism. It is the purpose.

[0009]

According to a first aspect of the present invention, there is provided a transmission having a main shaft rotatably driven by a drive engine inside a casing, and a main shaft arranged in parallel with the main shaft. A transmission having a transmission in which a counter shaft is rotatably disposed, gears of a plurality of speeds are disposed on the outer periphery of each shaft, and the respective gears are meshed by a synchromesh transmission mechanism. A rotary drum having a change cam groove formed on an outer peripheral surface thereof is provided in the vicinity of the transmission so as to be rotatable, and the rotary drum is rotated by a predetermined angle by a linear shift operation by a shift operation lever. When the transmitter is operated following the change cam groove of the rotary drum, A transmission shaft for operating a synchromesh transmission mechanism of the vehicle, and the reverse gear shifting mechanism is configured to stop the main shaft by synchronizing the rotation of the synchromesh transmission mechanism by a change mechanism for the first to fifth speeds. A change cam groove of the rotary drum is formed so that the shaft can be operated.

According to the first aspect of the present invention, at the time of reverse gear shifting, the rotation shaft of the rotary drum follows the changing cam groove to operate, thereby operating the gear shift shaft for the first to fifth gears of the synchromesh transmission mechanism. Since the main shaft is stopped by the synchronizing action of the rotation by the change mechanism, the gear can be reversely changed in a state where the rotation of the main shaft is stopped. Nothing. In addition, since the rotation synchronizing action of the change mechanism for the first to fifth speeds incorporated in the synchromesh transmission mechanism in advance is used, a reverse brake mechanism is not required, and the structure is simple and can be easily manufactured. is there.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 show an embodiment of a transmission according to the present invention. The transmission of this embodiment comprises a rotary drum change mechanism 2 housed inside a casing 1. And a transmission 3. The casing 1 includes a clutch-side casing 1 a.
And the transmission side casing 1b.

The drum change mechanism 2 is operated by a shift operation lever 6 provided on a column 5 that supports a steering wheel 4 of a vehicle. In the present embodiment, the shift operation lever 6 is For example, an upshift operation is performed by swinging backward, and a downshift operation is performed by swinging forward. The shift patterns are set in the order of R (reverse), 1st speed, N (neutral), 2nd speed, 3rd speed, 4th speed, and 5th speed. In this case, the first speed in the present embodiment is, for example,
It is a forward gear like a so-called super low with a large gear ratio set, and can start from the second speed in normal running.

A support plate 8 located on the outer peripheral side of the handle shaft 7 is provided inside the column 5, and a lower end of the support plate 8 has a tip portion on the side of the column 5. The base end of the extending shift operation lever 6 is rotatably mounted. At the base end of the shift operation lever, the base end of a drive lever 9 extending vertically in FIG. 2 is fixed integrally with the shift operation lever 6. , A wire connecting portion 10 is provided. One end of a shift cable 12 in which a drive wire 11 is accommodated is fixed to the side of the handle shaft 7. One end of the drive wire 11 is connected to a wire connecting portion of the drive lever 9. 10 is connected. By operating the shift operation lever 6 forward or backward, the drive lever 9 is rotated,
Thus, the drive wire 11 is pulled out or pushed in. With this configuration, the shift operation can be easily performed without releasing the hand from the handle 4, and the shift operability can be improved.

As shown in FIG. 1, the drum change mechanism 2 has a cylindrical rotating drum 13, and the peripheral surface of the rotating drum 13 has a predetermined shape in this embodiment. Thus, four changing cam grooves 14 extending in the circumferential direction are formed. Each of these change cam grooves is composed of a 1-2 speed change cam groove 14a,
Fourth-speed change cam groove 14b, Five-speed change cam groove 1
4c and a reverse change cam groove 14d, which is a reverse change cam groove 14d from the left in FIG. 1, and a 1-2 speed change cam groove. Cam groove 14
a, 3-4 speed change cam grooves 14b and 5 speed change cam grooves 14c.

The rotary drum 13 is driven to rotate by a predetermined angle by operating the shift operation lever 6, and positions at which the rotary drum 13 rotates by a predetermined angle are R, 1st speed, N, 2nd, 3rd, 4th, 5th
The gear shift position is set to a high speed. And FIG.
As shown in detail in FIG. 2, the cam groove 14a for the 1-2 speed change of the rotary drum 13 has a position corresponding to the case where the rotary drum 13 is rotated by a predetermined angle in the forward and reverse directions around the N position (N). The 1-2 speed change cam groove 14a
In FIG. 5, a first-gear position (1) bent substantially to the left and a second-gear position (2) bent substantially to the right in FIG. 5 are formed. The cam groove 14b for 3-4 speed change of the rotary drum 13 is provided with a position corresponding to the case where the rotary drum 13 is rotated in the forward direction by a predetermined angle from the second speed position (2).
The third speed position (3) in which the −4 speed change cam groove 14b is bent substantially in the shape of a left side in FIG. 4) are formed respectively. The cam groove 14c for the fifth speed change of the rotary drum 13 has the fourth speed position (4).
The fifth speed position (5) is formed by bending the fifth speed change cam groove 14c so as to be inclined leftward in FIG. 5 at a position corresponding to the case where the rotary drum 13 is rotated by a predetermined angle in the forward direction. The reverse change cam groove 14d of the rotary drum 13 is provided with a reverse change cam groove 14d at a position corresponding to the case where the rotary drum 13 is rotated in the reverse direction by a predetermined angle from the first speed position. Is formed so as to be inclined rightward in FIG. 5. Further, in this embodiment, the cam groove 1 for the 1-2 speed change of the rotary drum 13 is used.
5A, between the first speed position (1) and the R position (R).
, A brake position (B) bent slightly to the right is formed. These change cam grooves 1
In the present embodiment, 4a, 14b, 14c, and 14d are formed with their phases shifted from each other in the circumferential direction.

As shown in FIGS. 6 and 15, on one end surface of the rotary drum 13, a rotation support portion 15 which is slightly projected in the axial direction is formed. A screw hole 16 is formed in the portion, and two fitting holes 17 are formed in the end face of the rotation support portion 15.
Are formed so as to be symmetrical in the diameter direction.

As shown in FIGS. 6 to 11, a drum center 18 is disposed coaxially with the rotary drum 13 on one end surface of the rotary drum 13. A stopper cam 19 and a detent cam 20 located on the rotary drum 13 side are formed integrally with each other. A mounting portion 21 having the same diameter as the rotation support portion 15 of the rotary drum 13 is integrally formed on an end surface of the drum center 18 on the rotary drum 13 side, and the mounting portion 21 includes: The cutout groove 22 extending in the radial direction is formed so as to be symmetrical in the radial direction. Further, a through hole 23 is formed in the center of the drum center 18, and a fastening portion 24 having an inner diameter larger than the through hole 23 is formed inside the stopper cam 19. Have been. A shifter accommodating portion 25 is formed inside the moderating cam 20, and a plurality of trapezoidal shapes (in this embodiment, the number of shift patterns is 7) is formed on the inner peripheral surface of the shifter accommodating portion 25. Are formed so as to have a predetermined interval in the circumferential direction.

The notch groove 2 of the drum center 18
A stopper pin 27 protruding in the axial direction is provided inside the drum 2, and the drum center 18 is attached to one end surface of the rotating drum 13 so that the stopper pin 27 is fitted into the fitting hole 17 of the rotating drum 13. In this state, a male screw is formed at the tip and a bolt is integrally formed at an intermediate part of the rotary support shaft 28. The rotary support shaft 28 is passed through the through hole 23 of the drum center 18, and the screw hole of the rotary drum 13 is formed. 16
The drum center 18 is integrally fixed to one end of the rotating drum 13 by being screwed and tightened. Further, the outer peripheral portions of the rotation supporting portion 15 of the rotating drum 13 and the mounting portion 21 of the drum center 18 are provided with the rotating drum 13 and the drum center 1.
A bearing 29 for supporting the bearing 8 is provided.
The rotation drum 13 and the drum center 18
Are driven to rotate integrally with the rotation support shaft 28 as a center.

On the outer peripheral surface of the stopper cam 19 of the drum center 18, arc-shaped stopper recesses 30 corresponding to the number of shift speeds (seven in this embodiment, the number of shift patterns) are provided. It is formed so as to have a predetermined interval in the circumferential direction, and between each of the stopper recesses 30 is formed in a roof shape so that the central portion projects most. Each stopper recess 30 of the stopper cam 19
Is the R of each change cam groove 14 of the rotary drum 13.
The first, second, third, fourth, and fifth speed positions are respectively arranged corresponding to the first, second, third, and fourth speed positions.

In the vicinity of the drum center 18, a stopper support shaft 31 is disposed in parallel with the rotary support shaft 28. The stopper support shaft 31 has a tip portion formed by the stopper cam 19. A drum stopper arm 32 extending to the outer peripheral portion is attached rotatably about its base end. Further, the drum stopper arm 32
A pressure roller 33 having a diameter corresponding to the arc of the stopper recess 30 is rotatably attached to the tip of the drum so as to be engaged with the stopper recess 30 of the stopper cam 19. One end of a stopper spring 34 attached to the stopper support shaft 31 is engaged with the base end of the stopper arm 32. Then, the pressing roller 33 of the drum stopper arm 32 is moved by the urging force of the stopper spring 34 to the stopper cam 1.
The stopper roller 33 of the drum stopper arm 32 engages with the stopper recess 30 of the stopper cam 19 by pressing the outer peripheral surface of the stopper 9.
The stopper cam 19 is prevented from rotating, and is kept at a fixed rotational position.

On the outer peripheral surface of the moderating cam 20 of the drum center 18, arc-shaped moderating recesses 35 corresponding to the number of gears (seven in this embodiment) are provided at predetermined intervals in the circumferential direction. The moderating recesses 35 of the moderating cam 20 are provided at the R position, the 1st speed position, the N position, and the 2nd changing cam groove 14 of the rotary drum 13, respectively.
The gears are arranged to correspond to the speed position, the third speed position, the fourth speed position, and the fifth speed position, respectively. In the present embodiment, at each end of each moderating recess 35, an inclined surface 36 whose corner is dropped is formed.
At the first-speed position side end and the R-position side end of the moderation concave portion 35 corresponding to the position and the first-speed position, a load portion 37 having a corner portion left is formed, and a moderation portion corresponding to the R position is formed. The recess 35 is formed such that its depth dimension is reduced.

A detent support shaft 38 is disposed near the drum center 18 in parallel with the rotary support shaft 28, and the detent support shaft 38 has a distal end formed with the detent cam 20. A moderating arm 39 extending to the outer peripheral portion is attached rotatably about its base end. At the tip of the moderating arm 39, a pressing roller 40 having a diameter matching the arc of the moderating concave 35 is rotatably engaged with the moderating concave 35 of the moderating cam 20. One end of a moderation spring 41 attached to the moderation support shaft 38 is engaged with the base end of the moderation arm 39. The urging force of the detent spring 41 presses the pressure roller 40 of the detent arm 39 against the outer peripheral surface of the detent cam 20, and the detent cam 20 rotates to reduce the detent. The press-contact roller 40 of the moderation arm 39 is engaged with the moderation recess 35 so as to impart a certain moderation to the swing operation of the shift operation lever 6.

A drum shifter 42 is loosely fitted to the end of the rotation support shaft 28 so as to be freely rotatable with respect to the rotation support shaft 28. The drum shifter 42 is provided on the end side of the rotation support shaft 28. A shift drive gear 43 is formed on the outer peripheral surface.

As shown in FIGS. 12 to 14, the other end of the drum shifter 42 is located inside the shifter accommodating portion 25 of the drum center 18.
On the other end side of the drum shifter 42, pin accommodating portions 44, 44 each having an outer peripheral surface cut out in a substantially C shape are formed symmetrically with respect to the center of the drum shifter 42. A small-diameter portion 45 that reduces the diameter of the drum shifter 42 is formed between the shift drive gear 43 of the drum shifter 42 and the pin housing portion 44.
Numeral 4 communicates with the small diameter portion 45.
Plunger holes 46, 46 opening inside the pin housings 44 are provided on one side inside the pin housings 44.
The plunger 47 urged in a direction projecting from the plunger hole 46 is accommodated in the plunger hole 46 so as to be able to advance and retreat. Further, a ratchet pin 48 is held in the pin housing portion 44 so that a base end thereof is held inside the pin housing portion 44, and a tip end of the plunger 47 abuts a side portion of the tip end. The ratchet pins 48 are swingable about the base end, and protrude from the outer periphery of the drum shifter 42 by the urging force of the plunger 47 to accommodate the shifter pins of the drum center 18. The portion 25 is adapted to be engaged with the ratchet engagement groove 26.

As shown in FIGS. 15 and 16,
On the outer peripheral side of the small diameter portion 45 of the drum shifter 42,
A guide plate 49 held by the casing 1 is provided, and the small-diameter portion 45 is provided substantially at the center of the guide plate 49.
A guide hole 50 in which is located is formed. The lower arc portion of the guide hole 50 has a diameter larger than the bottom of the ratchet engaging groove 26 so as not to prevent the ratchet pin 48 from engaging with the ratchet engaging groove 26 of the drum center 18. When the ratchet pin 48 comes into contact with the upper arc portion due to the rotation of the drum shifter 42, the upper arc portion of the guide hole 50 resists the ratchet pin 48 against the urging force of the plunger 47. The drum shifter 42 is formed to have a diameter substantially similar to the diameter of the drum shifter 42 so as to be accommodated in the pin accommodation portion 44 of the drum shifter 42. Further, the guide plate 49 is formed with a rotation preventing projection 51 which abuts on an edge of the casing 1 and prevents the guide plate 49 from rotating.

On one side of the drum shifter 42, a drive arm 52 extending in a direction orthogonal to the rotation support shaft 28 is swingable about a base end located at a position most distant from the drum shifter 42. The end of the drive arm 52 is provided with the drum shifter 42.
A drive gear 53 meshed with the shift drive gear 43 is formed. A return spring 54 is attached to the base end of the drive arm 52. When the drive arm 52 swings, the drive arm 52 is always returned to a predetermined reference position. I have. further,
A shift lever 55 located outside the casing 1 is connected to a base end of the drive arm 52. A distal end of the shift lever 55 is connected to the other end of the drive wire 11 of the shift cable 12. Are connected via a coupler 56. Then, by operating the shift operation lever 6 and pulling out or pushing in the drive wire 11 via the drive lever 9, the shift lever 55 is swingably driven, whereby the drive arm 52 is moved. The drum shifter 42 can be driven to rotate by a shift drive gear 43 meshed with a drive gear 53 of the drive arm 52 by swinging drive.

As shown in FIGS. 1 and 17, near the rotating drum 13 inside the casing 1,
2 speed shaft 57, 3-4 speed shaft 58 and 5
The -R transmission shaft 59 is disposed in parallel with the rotation axis of the rotary drum 13, and the 1-2 transmission shaft 57, the 3-4 transmission shaft 58, and the 5-R transmission shaft 59 move in the axial direction, respectively. It is freely supported.

As shown in FIGS. 17 and 18,
A 1-2 speed cam pin 60 which is engaged with the 1-2 speed change cam groove 14a of the rotary drum 13 is formed on the outer periphery of the 1-2 speed change shaft 57 so as to protrude therefrom.
A 1-2 shift fork 61 having a substantially C-shaped tip is integrally fixed to the 2 shift shaft 57.
When the rotating drum 13 is driven to rotate,
The 1-2 speed cam pin 60 follows along the 1-2 speed change cam groove 14a, and the 1-2 speed change cam groove 14
The 1-2 shift shaft 57 is moved in the axial direction according to the shape of a, and accordingly, the 1-2 shift fork 61 is also moved.

Similarly, on the outer periphery of the 3-4 speed change shaft 58, a 3-4 speed cam pin 62 which is engaged with the 3-4 speed change cam groove 14b of the rotary drum 13 is formed so as to protrude therefrom. A 3-4 speed change fork 63 having a substantially C-shaped tip is integrally fixed to the 3-4 speed change shaft 58. The rotation of the rotary drum 13 causes the 3-4 speed change cam groove 14b to move along the 3-4 speed change cam groove 14b.
The 3-4 speed change shaft 58 and the 3-4 speed change fork 63 are moved in the axial direction according to the shape of the 3-4 speed change cam groove 14b.

A 5-speed change cam groove 14 of the rotary drum 13 is provided on the outer periphery of the 5-R transmission shaft 59.
A 5-speed cam pin 64 is formed so as to protrude therefrom.
A five-speed fork 65 formed in the shape of a letter is integrally fixed. The rotation of the rotary drum 13 causes the fifth speed cam pin 64 to follow the fifth speed change cam groove 14c, and the fifth speed cam pin 64 follows the shape of the fifth speed change cam groove 14c.
The -R shift shaft 59 and the five-speed fork 65 are moved in the axial direction.

Further, a reverse shift bush 66 is provided on the 5-R shift shaft 59.
The reverse shift bush 66 is formed with a reverse cam pin 67 which is engaged with the reverse change cam groove 14d of the rotary drum 13 so as to protrude. The rotation of the rotary drum 13 causes the reverse cam pin 67 to follow the reverse change cam groove 14d, and the reverse speed change bush 66 moves to the 5-R speed change shaft 59 according to the shape of the reverse change cam groove 14d. It is to be moved along.

As shown in FIGS. 19 and 20,
At the other end of the rotary drum 13, a shift position cam 68 is mounted coaxially with the rotary drum 13.
The outer periphery of the shift position cam 68 corresponds to the R position, first speed position, N position, second speed position, third speed position, fourth speed position, and fifth speed position of each change cam groove 14 of the rotary drum 13 respectively. A cam surface 69 for recognizing the current shift position by changing the height of the shift position is formed. That is, in the present embodiment, the cam surface 69
Are set at four types of height positions, a maximum position, a high position, a standard position, and a low position. The R position is the maximum position, the 1st position is the low position, the N position is the standard position, The shift positions are formed so that adjacent shift positions have different heights so that the high speed position is the high position, the third speed position is the highest position, the fourth speed position is the low position, and the fifth speed position is the high position. Further, all of the positions between the R position, the first speed position, the N position, the second speed position, the third speed position, the fourth speed position, and the fifth speed position are formed to have the height of the N position, that is, the standard position.

A shift position sensor 70 is provided in the vicinity of the outer periphery of the shift position cam 68, and a tip end of the shift position sensor 70 is provided on the cam surface 69 of the shift position cam 68. An abutting sensor plunger 71 is provided so as to be able to advance and retreat in the radial direction of the shift position cam 68.

The shift position sensor 70
In, the current shift position is recognized based on the advance / retreat position of the sensor plunger 71 of the shift position sensor. Moreover, in this embodiment, a detection circuit (not shown) for detecting whether the swing operation of the shift operation lever 6 is a shift-up operation or a shift-down operation is provided. The next shift position is predicted based on the detection information of the down operation, and the predicted shift position is compared with the shift position detected by the advance / retreat position of the sensor plunger 71 of the shift position sensor 70 to determine each shift position. Arithmetic circuits for checking whether or not they are the same are provided. This arithmetic circuit may use, for example, a computer mounted on the vehicle in advance, or may be provided separately.

If, for example, the current shift position is at the N position and the upshift operation is performed from this state, the second speed is achieved, the rotation of the rotary drum 13 by this upshift operation causes the cam of the shift position cam 68 to rotate. The surface 69 is at the high position, and if the gear is shifted down, the first speed is attained. Therefore, when it is recognized that the detection information of the up / down operation of the shift operation lever 6 is an upshift operation, the sensor plunger 71 of the shift position sensor 70 moves forward and backward by the cam surface 69 of the low position of the shift position cam 68. Position of the shift position sensor 70.
If the shift position detected based on the advance / retreat position of 1 and the shift position based on the detection information of the up / down operation match, it can be confirmed that the shift positions are the same.

The present shift position is recognized by comparing the shift position detected by the shift position sensor 70 with the up / down operation information by the shift operation of the shift operation lever 6. Therefore, by combining the cam height of the cam surface 69 of the shift position cam 68 so as to be different at the adjacent shift position, the height of the cam surface 69 of the shift position cam 68 is not changed at each shift position. Each shift position can be recognized at four types of height positions.

Next, the transmission 3 of the present embodiment
Will be described with reference to FIG.

First, a main shaft 7 connected to a driving engine such as an engine (not shown) is provided inside the casing 1.
2 is rotatably disposed by a bearing 29, and a counter shaft 73 is provided near the main shaft 72.
Are arranged rotatably by bearings 29 and parallel to the main shaft 72. Further, as shown in FIG. 22, a reverse shaft 74 is provided in parallel with the main shaft 72 and the counter shaft 73.

A first speed main gear 75, a reverse main gear 76, and a second speed main gear 77 are integrally fixed on the outer periphery of the main shaft 72 with a predetermined number of teeth, respectively. In
A third-speed main gear 78, a fourth-speed main gear 79, a fifth-speed main gear 80, and a cone ring 81 are freely rotatably disposed on the main shaft 72 via bearings.

A 3-4 speed hub 82 having a gear formed on the outer peripheral surface thereof is provided on the outer periphery of the main shaft 72 and between the 3rd speed main gear 78 and the 4th speed main gear 79.
The 3-4 speed hub 82 is provided with a 3-4 speed sleeve 84 having a gear formed on the inner peripheral surface thereof and a fork engaging groove 83 provided on the outer periphery thereof. It is arranged movably in the axial direction of the shaft 72,
The 3-4 speed change fork 63 is engaged with the fork locking groove 83. The movement of the 3-4 speed change fork 63 causes the 3-4 speed sleeve 84 to move in the axial direction of the main shaft 72.

Further, a tapered inclined surface is formed on the outer peripheral surface of the third speed main gear 78 and near the 3-4 speed hub 82, and on the outer peripheral side of the inclined surface, 3-speed synchronizer ring 8 with gears formed on the outer circumference
5 are provided. Further, a tapered inclined surface is formed on the outer peripheral surface of the fourth speed main gear 79 and in the vicinity of the 3-4 speed hub 82, and a gear is formed on the outer peripheral side of the inclined surface. A synchronizer ring 86 for the fourth speed in which is formed is provided. With such a configuration,
A 3-4 speed synchromesh mechanism is formed.

In the 3-4 speed synchromesh mechanism, the 3-4 speed sleeve 84 is moved to the 3rd speed main gear 78 side, so that the gear of the 3-4 speed sleeve 84 and the 3rd speed sleeve 84 are moved. Synchronizer ring 85
, And the rotation of the sleeve 84 for 3-4 speed is synchronized. When the synchronizing operation is completed, the rotational difference between the third- and fourth-speed sleeves 84 and the third-speed main gear 78 is eliminated, and the gears of the third- and fourth-speed sleeves 84 mesh with the third-speed main gear 78, and the synchronization operation is completed. The driving force is transmitted by the gear ratio of the third speed main gear 78.

When the 3rd-4th speed sleeve 84 is moved toward the 4th speed main gear 79, the gears of the 3rd-4th speed sleeve 84 mesh with the 4th speed main gear 79, and The driving force is transmitted by the gear ratio.

Further, a 5-speed synchromesh mechanism similar to the 3-4 speed synchromesh mechanism is formed on the outer periphery of the main shaft 72 and between the 5-speed main gear 80 and the cone ring 81. You.

An output gear 92 is integrally fixed to the outer periphery of the counter shaft 73, and the first speed main gear 7 is fixed to the outer periphery of the counter shaft 73.
A first-speed counter gear 93 constantly meshed with the gear 5 and a second-speed counter gear 94 constantly meshed with the second-speed main gear 77 are arranged freely rotatable with respect to the counter shaft 73 via bearings. I have.
Further, on the outer periphery of the counter shaft 73, a third speed counter gear 95 constantly meshed with the third speed main gear 78, a fourth speed counter gear 96 constantly meshed with the fourth speed main gear 79, and the fifth speed main gear A five-speed counter gear 97 which is always meshed with 80 is integrally fixed with a predetermined number of teeth.

A gear is formed on the outer peripheral surface of the counter shaft 73 between the first speed counter gear 93 and the second speed counter gear 94.
The speed hub 98 is fixed, and the 1-2 speed hub 9 is fixed.
On the outer periphery of the gear 8, a 1-2 speed sleeve 100 having a gear formed on the inner peripheral surface and a fork engaging groove 99 provided on the outer periphery is disposed so as to be movable in the axial direction of the counter shaft 73. The fork locking groove 99 has the 1
-2 shift fork 61 is engaged. The 1-2 speed sleeve 100 is moved in the axial direction of the counter shaft 73 by the movement of the 1-2 shift fork 61.

Further, a tapered inclined surface is formed on the outer peripheral surface of the first-speed counter gear 93 and near the 1-2 speed hub 98, and on the outer peripheral side of the inclined surface, A first-speed synchronizer ring 101 having a gear formed on the outer periphery is provided. Further, a tapered inclined surface is formed on the outer peripheral surface of the second-speed counter gear 94 and near the 1-2 speed hub 98, and a gear is provided on the outer peripheral side of the inclined surface. The synchronizer ring 102 for the second speed in which is formed is provided. With such a configuration, a 1-2 speed synchromesh mechanism is formed.

In the 1-2 speed synchromesh mechanism as well, by rotating the 1-2 speed sleeve 100 to the 1st speed counter gear 93 or the 2nd speed counter gear 94, the rotation is synchronized. As a result, the gear of the 1-2 speed sleeve 100 meshes with the first speed counter gear 93 or the second speed counter gear 94, and the driving force is transmitted by the gear ratio of the first speed counter gear 93 or the second speed counter gear 94. Become.

Further, in the present embodiment, the above 1-
A reverse counter gear 103 is formed on the outer peripheral surface of the second speed sleeve 100, and a reverse idle gear 104 is loosely fitted on the reverse shaft 74. The reverse idle gear 104 is moved in the axial direction of the reverse shaft 74 by the movement of the reverse speed change bush 66. By the movement of the reverse idle gear 104, the reverse idle gear 104 The reverse main gear 76 and the reverse counter gear 103 of the counter shaft 73 are meshed with each other.

An output gear 92 of the counter shaft 73 is meshed with an input gear 106 of a differential gear mechanism 105. An output shaft 107 of the differential gear mechanism 105 is connected to a drive unit such as a wheel (not shown). It has been made to be.

The rotary drum change mechanism 2
The transmission 3 is accommodated in the casing 1 by attaching the transmission-side casing 1b to the clutch-side casing 1a in a state where the members are assembled inside the clutch-side casing 1a. In this case, in the present embodiment, the main shaft 7 of the transmission 3
2 and the counter shaft 73 and the rotating shaft of the rotating drum 13 are all arranged in parallel, so that they can be easily housed in the casing 1 and the assemblability can be significantly improved. Can enhance the workability of the steel.

Next, the operation of the present embodiment will be described.

First, in the neutral state, the drum stopper arm 3 is inserted into the stopper recess 30 corresponding to the N position of the stopper cam 19 of the drum center 18.
The second pressing roller 33 is engaged with the rotating drum 13.
Are held at the N position. In this state, the 1-speed change cam groove 14a of the rotary drum 13
2nd speed cam pin 60, 3rd / 4th speed cam pin 62 in 3rd / 4th speed change cam groove 14b, 5th speed change cam groove 1
The fifth speed cam pin 64 in 4c and the reverse cam pin 67 in the reverse change cam groove 14d are respectively located at the N position, and the 1-2 speed fork 61,
The 3-4 speed fork 63 and the 5 speed fork 65 are not moved, and the 1-2 speed sleeve 100, the 3-4 speed sleeve 84 and the 5 speed sleeve 89 are located in the middle.

Therefore, even when the rotational force is transmitted to the main shaft 72, the third speed main gear 78, the fourth speed main gear 79 and the fifth speed main gear 80 are connected to the main shaft 7
2 and the first-speed main gear 75 and the second-speed main gear 77
3, the rotation of the main shaft 72 is not transmitted to the counter shaft 73, and the counter shaft 73 is kept in a non-rotating state.

In this case, the sensor plunger 71 of the shift position sensor 70 is
8 is in contact with the cam surface 69 corresponding to the N position, indicating that the current shift position is the N position, that is, neutral.

When shifting up to the second speed from this state, the drive lever 9 is pivoted rearward in FIG. 2 by swinging the shift operation lever 6 backward to drive the shift cable 12. The wire 11 is pulled out, and the shift lever 55 is driven to swing by the pulling-out operation of the drive wire 11. This shift lever 5
The swing of 5 causes the drive arm 52 to swing, and the shift drive gear 43 meshed with the drive gear 53 of the drive arm 52 drives the drum shifter 42 to rotate clockwise in FIG.

When the drum shifter 42 is rotated in this way, as shown in FIG. 12, a ratchet pin 48 having a tip in the rotation direction of the drum shifter 42 is
The ratchet pin 48 is engaged with the ratchet engaging groove 26 of the shifter housing portion 25 of the drum center 18 because the ratchet pin 48 projects outward from the pin housing portion 44 of the drum shifter 42 by the urging force of the drum center 18. The rotating drum 13 is rotated together with the drum shifter 42.
As the drum shifter 42 rotates in this way, FIG.
As shown in the figure, the ratchet pin 48 having a tip in the anti-rotational direction comes into contact with the upper arc portion of the guide plate 49 and is housed in the pin housing portion 44 of the drum shifter 42 against the urging force of the plunger 47. Becomes

On the other hand, the rotation of the drum center 18 causes the pressing roller 33 of the drum stopper arm 32 to rotate.
Is disengaged from the stopper concave portion 30 of the stopper cam 19 against the urging force of the stopper spring 34, is engaged with the stopper concave portion 30 corresponding to the second speed position of the stopper cam 19, and the rotating drum 13 is moved. It is held at the second speed position. In this case, the pressing roller 40 of the moderating arm 39 is pressed by the moderating recess 3 of the moderating cam 20 against the urging force of the moderating spring 41.
5 and engages with the adjacent moderation recess 35, a certain moderation is imparted to the swing operation of the shift operation lever 6. As a result, it is possible to intuitively recognize that the shift has been performed when performing the shift operation.

When the shift operation lever 6 is released after the shift operation is completed, the return spring 5 of the drive arm 52 is released.
4, the urging force is applied so that the drive arm 52 returns to the original position, and the urging force of the urging spring applies a force to rotate the drum shifter 42 in the direction opposite to the speed change operation.

At this time, the pressing roller 33 of the drum stopper arm 32 is connected to the stopper recess 3 of the stopper cam 19.
0, the drum center 18 and the rotating drum 13 are held at the same position by the urging force of the pressing roller 33. On the other hand, the rotational force applied to the drum shifter 42 causes the ratchet pin 48 engaged with the ratchet engaging groove 26 of the drum center 18 to move into the ratchet engaging groove 26 as shown in FIG.
Is swung toward the center of the drum shifter 42 against the urging force of the plunger 47 and accommodated in the pin accommodating portion 44, and the other ratchet pin 48 is pinned by the upper arc portion of the guide plate 49. Since the drum shifter 42 is accommodated in the accommodating portion 44, the drum shifter 42
And each ratchet pin 48 is independently rotated with respect to
Are engaged with the adjacent ratchet engaging grooves 26, and the rotation of the drum shifter 42 is stopped. As a result, the drive arm 52 returns to the original position, and the shift operation lever 6 is returned to the original position via the shift lever 55 and the drive wire 11.

When the rotary drum 13 is held at the second speed position, the shift position cam 68 attached to the other end of the rotary drum 13 is also rotated.
The shift position sensor 70 detects the second gear position based on the advance / retreat position of the sensor plunger 71 and displays a predetermined shift position.

The rotation of the rotary drum 13 causes the 1-2 speed cam pin 60 to follow the 1-2 speed change cam groove 14a, depending on the shape of the 1-2 speed change cam groove 14a. The 1-2 transmission shaft 57 is moved rightward in FIG. Accordingly, 1-
The 2-speed fork 61 is moved, and the 1-2 speed sleeve 100 of the 1-2 speed synchromesh mechanism is moved to the 2nd speed counter gear 94 side. The gear of the speed sleeve 100 is meshed with the second speed counter gear 94. As a result, the rotational force of the main shaft 72 is transmitted to the counter shaft 73 via the second speed main gear 77 and the second speed counter gear 94, and the output shaft 107 of the differential gear mechanism 105 is transmitted via the output gear 92 and the input gear 106. It rotates at a predetermined gear ratio.

Also, from the second speed state to the third speed, from the third speed state to the fourth speed
The same applies when shifting up from the fourth and fourth gear states to the fifth gear, respectively.

By shifting the shift operation lever 6 backward once, the gear can be shifted up one speed at a time.

Next, the operation of shifting down will be described.

For example, when shifting down from the above-mentioned fifth speed state to the fourth speed state, the drive lever 9 is rotated counterclockwise in FIG. 2 by swinging the shift operation lever 6 forward. Then, the drive wire 11 of the shift cable 12 is pushed, and the shift lever 55 is driven to swing by the push operation of the drive wire 11. The swing of the shift lever 55 causes the drive arm 52 to swing, and the drive gear 53 of the drive arm 52
The shift drive gear 43 meshed with the drum shifter 4
2 is driven to rotate counterclockwise in FIG.

When the drum shifter 42 is rotated in this manner, the ratchet pin 48 on the side opposite to that in the case of the upshift operation is pressed by the plunger 47 so that the ratchet engaging groove of the shifter housing 25 of the drum center 18 is formed. 2
6, the drum center 18 and the rotating drum 1
3 is rotated together with the drum shifter 42 in a direction opposite to that in the upshift.

In this case, the rotation of the drum center 18 imparts a certain moderation to the swinging operation of the shift operation lever 6 by the moderation cam 20, while the rotation drum 13 is moved to the fourth speed position by the stopper cam 19. Will be retained.
Thereafter, when the shift operation lever 6 is released, the drive arm 52 returns to the original position by the ratchet operation of the drum shifter 42 by the urging force of the return spring 54 of the drive arm 52, and the shift lever 55 and the drive wire The shift operation lever 6 is also returned to the original position via 11.

Then, the rotation of the rotary drum 13 causes the fifth speed cam pin 64 to follow the fifth speed change cam groove 14c, and the 5-R transmission shaft 59 is moved rightward in FIG. Accordingly, the fifth speed sleeve 89 is moved to the fifth speed main gear 80 by the five speed fork 65.
And the gear of the fifth-speed sleeve 89 is disengaged from the fifth-speed main gear 80. On the other hand, the 3-4 speed cam pin 62 follows the 3-4 speed change cam groove 14b, and the 3-4 speed fork 63 is moved by the 3-4 speed shaft 58 so that the gear of the 3-4 speed sleeve 84 is moved. Are meshed with the fourth speed main gear 79. As a result, the rotational force of the main shaft 72 is changed by the gear ratio of the fourth speed main gear 79 to the output shaft 10 of the differential gear mechanism 105.
7 is transmitted.

When the shift-down operation is performed as described above, the shift operation lever 6 is operated to swing forward, as opposed to the shift-up operation.
It is possible to shift down by speed.

Next, the case of shifting to the first speed and the reverse will be described.

First, when shifting from the neutral state to the first speed, the drive wire 11 of the shift cable 12 is pushed in by operating the shift operation lever 6 to swing forward as in the case of the downshift. Thus, the drum shifter 42 is driven to rotate via the shift lever 55 and the drive arm 52, and the drum center 18 and the rotating drum 13 are rotated. The rotation of the drum center 18 causes the moderation recess 3 of the pressing roller 40 of the moderation arm 39 to move.
The stopper recess 3 corresponding to the first speed position of the pressing roller 33 of the drum stopper arm 32 while imparting a certain moderation to the swing operation of the shift operation lever 6 by the engagement with the stopper 5.
The engagement with 0 causes the rotating drum 13 to be held at the first speed position.

In this case, in this embodiment, the load portion 37 is formed at the first speed position end of the moderation concave portion 35 corresponding to the N position of the moderation cam 20.
Is rotated, the pressing roller 40 of the moderating arm 39 is rotated.
Is disengaged from the moderation concave portion 35 corresponding to the N position of the moderating cam 20 against the biasing force of the moderating spring 41 and engages with the moderating concave portion 35 corresponding to the first speed position. Since the user goes over the section 37, a load is applied during the shift operation, and a moderation different from that in the case of the normal downshift is provided. Therefore, the shift operation lever 6
When shifting from the neutral state to the first gear by swinging the gear, a moderation different from that in the case of normal downshifting is provided so that it is possible to sensibly recognize that the gear is shifted to the first gear. ing.

Thereafter, when the shift operation lever 6 is released, the drive arm 52 returns to the original position by the ratchet operation of the drum shifter 42 by the urging force of the return spring 54 of the drive arm 52, and the shift lever 55
Also, the shift operation lever 6 is returned to the original position via the drive wire 11.

The rotation of the rotary drum 13 causes the 1-2 speed cam pin 60 to follow the 1-2 speed change cam groove 14a, depending on the shape of the 1-2 speed change cam groove 14a. The 1-2 transmission shaft 57 is moved leftward in FIG.
The 1-2 speed sleeve 100 is moved to the first speed counter gear 93 via the speed change fork 61, and the gear of the 1-2 speed sleeve 100 meshes with the first speed counter gear 93. As a result, the rotational force of the main shaft 72 is transmitted to the counter shaft 73 via the first speed main gear 75 and the first speed counter gear 93, and is transmitted through the output gear 92 and the input gear 106 to the differential gear mechanism 10.
5 rotates the output shaft 107 at a predetermined gear ratio.

Subsequently, in the case of shifting to reverse, as in the case of shifting to the first speed, the shift operation lever 6 is operated to swing forward so that the drive wires 11,
The drum shifter 42 is rotationally driven via the shift lever 55 and the drive arm 52, and the drum center 18 and the rotary drum 13 are rotated. The rotation of the drum center 18 provides a certain degree of moderation to the swing operation of the shift operation lever 6 by engagement of the moderation arm 39 with the moderation concave portion 35 of the pressing roller 40, while the drum stopper arm 32 Pressure roller 33
The rotary drum 13 is held at the first speed position by engaging the stopper concave portion 30 corresponding to the first speed position.

In this case, similarly to the case of shifting to the first speed, the rotation of the drum center 18 causes the moderating cam 20 to rotate.
Is rotated, the pressing roller 40 of the moderating arm 39 is rotated.
Is engaged with the moderation concave portion 35 corresponding to the R position,
Since the vehicle rides over the load portion 37, a load is applied during the shift operation, and a moderation different from that in the case of normal downshifting is provided. Therefore, when the shift operation lever 6 is rocked to shift from the first speed state to the reverse state, it is possible to sensibly recognize that the shift operation is in the reverse direction.

Thereafter, when the shift operation lever 6 is released, the drive arm 52 returns to the original position by the urging force of the return spring 54 of the drive arm 52, and the shift lever 55 and the drive wire 11 The shift operation lever 6 is also returned to the original position.

Then, as shown in FIGS. 21 and 22, the rotation of the rotary drum 13 causes the reverse cam pin 67 to follow the reverse change cam groove 14d, depending on the shape of the reverse change cam groove 14d. The reverse shift bush 66 is connected to the 5-R shift shaft 59.
17 is moved to the right in FIG. 17, and accordingly, the reverse idle gear 104
4, the reverse idle gear 10
4 is a reverse main gear 76 of the main shaft 72
And the counter shaft 73 is engaged with the reverse counter gear 103.

In this case, in this embodiment, one of the cam grooves 14a for the 1-2 speed change of the rotary drum 13 is formed.
Since the brake position is formed between the speed position and the R position, when the reverse speed is changed by the rotation of the rotary drum 13, the 1-2 speed cam pin is moved to the brake position of the 1-2 speed change cam groove 14a. By following 60, the 1-2 shift shaft 57 is slightly moved rightward in the figure. Accordingly, the 1-2 speed sleeve 100 is moved by the 1-2 speed fork 61 to the second speed counter gear 9.
The main shaft 72 is slightly moved to the fourth side, whereby the main shaft 72 is braked by synchronizing the rotation. Therefore, the reverse gear can be shifted in a state where the rotation of the main shaft 72 is stopped, and the reverse idle gear 104 is meshed with the reverse main gear 76 of the main shaft 72 and the reverse counter gear 103 of the counter shaft 73, respectively. In this case, there is no generation of abnormal noise caused by gear biting.

Then, in this state, the main shaft 72
Is transmitted to the counter shaft 73 via the reverse main gear 76, the reverse idle gear 104 and the reverse counter gear 103, respectively, and the output shaft 107 of the differential gear mechanism 105 via the output gear 92 and the input gear 106. It rotates in the reverse direction at the gear ratio.

Accordingly, in this embodiment, the rotary drum 13 is rotated by a predetermined angle by operating the shift operation lever 6 disposed on the column 5 of the handle 4 in a linear manner so that R, R 1st gear, N, 2nd gear, 3rd gear
Since the gears are sequentially shifted in the order of the fourth speed, the fifth speed, the shift operation can be reliably performed with a simple structure, and the shift operation lever 6 may be operated linearly. The shift operation can be easily performed, and an operation error of the shift operation lever 6 can be eliminated. Further, the shift operation of the shift operation lever 6 causes the rotary drum 13 to rotate via the shift cable 12 to perform a predetermined shift operation, so that the operating mechanism of the rotary drum 13 is simplified, and the shift Since the cable 12 has flexibility, the installation location of the shift operation lever 6 can be freely set.
The present invention can also be applied to a walk-through type vehicle.

Further, in this embodiment, when the reverse gear shift is performed, the main shaft 72 is synchronized with the rotation by the synchromesh transmission mechanism by the brake position of the cam groove 14a for 1-2 speed change of the rotary drum 13. , The reverse gear can be changed in a state in which the rotation of the main shaft 72 is stopped, and the noise of the gear biting during the reverse is not generated. In addition, since the rotation synchronizing action of the change mechanism for the first and second speeds incorporated in the synchromesh transmission mechanism in advance is used, it is not necessary to separately provide a reverse brake mechanism, and the structure is simple.
And it can be easily manufactured.

In the above-described embodiment, the shift operation of the shift operation lever 6 allows the first gear, the first gear, and the second gear to be shifted.
N, 2nd, 3rd, 4th and 5th gears are sequentially shifted. However, the shift operation of the shift operation lever 6 allows R, N, 1st, 2nd and 3rd gears. 4th gear,
It may be formed so that the shift is performed sequentially in the shift pattern of the fifth speed.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed.

[0087]

As described above, in the transmission according to the first aspect of the present invention, the synchromesh transmission is performed by operating the transmission shaft following the cam groove for change by the rotation of the rotary drum during the reverse transmission. Mechanism 1-5
Since the main shaft is stopped by the rotation synchronizing action of the speed change mechanism, it is possible to reverse the gear while the rotation of the main shaft is stopped. Does not occur. Moreover, since the rotation synchronizing action of the change mechanism for the first to fifth speeds which is pre-installed in the synchromesh transmission mechanism is used, a reverse brake mechanism is not required, and the structure is simple and easy to manufacture. It has effects such as being able to do.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a transmission according to the present invention.

FIG. 2 is a configuration diagram showing an embodiment of a rotary drum change mechanism and a shift operation lever of the present invention.

FIG. 3 is a front view showing another embodiment of the shift operation lever of the present invention.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a developed view showing a cam groove for changing the rotary drum of the present invention.

FIG. 6 is a longitudinal sectional view showing a drum center and a drum shifter according to the present invention.

FIG. 7 is a longitudinal sectional view showing the drum center of the present invention.

FIG. 8 is a perspective view of a moderation cam side showing the drum center of the present invention.

FIG. 9 is a perspective view of a stopper cam side showing the drum center of the present invention.

FIG. 10 is an explanatory diagram showing an engagement state between a stopper cam and a drum stopper arm of the drum center of the present invention.

FIG. 11 is an explanatory view showing an engagement state between a moderation cam and a moderation arm of the drum center of the present invention.

FIG. 12 is a front view showing a stationary state of the drum shifter according to the present invention;

FIG. 13 is an explanatory diagram showing a rotating operation state of the drum shifter of the present invention.

FIG. 14 is an explanatory diagram showing a rotation return state of the drum shifter of the present invention.

FIG. 15 is a vertical sectional view showing a drum center and a drum shifter according to the present invention.

FIG. 16 is a front view of a guide plate portion of the present invention.

FIG. 17 is a plan view showing a transmission shaft and a transmission fork of the present invention.

18 is a side view of FIG.

FIG. 19 is a longitudinal sectional view showing a shift position cam portion of the present invention.

FIG. 20 is a front view showing a shift position cam portion of the present invention.

FIG. 21 is an explanatory view showing an operation state of the speed change shaft by the change cam groove of the present invention.

FIG. 22 (a), (b), (c), (d)
Is an explanatory diagram showing the meshing state of the gears in each state of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Drum change mechanism 3 Transmission 4 Handle 6 Shift operation lever 11 Drive wire 12 Shift cable 13 Rotary drum 14 Change cam groove 18 Drum center 19 Stopper cam 20 Moderation cam 26 Ratchet engagement groove 30 Stopper recess 32 Drum stopper arm 35 Moderation recess 37 Load section 39 Moderation arm 42 Drum shifter 48 Ratchet pin 49 Guide plate 52 Drive arm 57 1-2 speed change shaft 58 3-4 speed change shaft 59 5-R speed change shaft 61 1-2 speed change fork 63 3-4 shift fork 65 5 shift fork 68 shift position cam 70 shift position sensor 71 sensor plunger 72 main shaft 73 counter shaft 74 reverse shaft 7 1st speed main gear 76 reverse main gear 77 2nd speed main gear 78 3rd speed main gear 79 4th speed main gear 80 5th speed main gear 92 output gear 93 1st speed counter gear 94 2nd speed counter gear 95 3rd speed counter gear 96 4th speed counter Gear 97 5-speed counter gear 103 Reverse counter gear 105 Differential gear mechanism

Claims (1)

[Claims] 1. A main shaft rotatably driven by a driving engine and a counter shaft arranged in parallel with the main shaft are rotatably disposed inside a casing, and a plurality of gears of a plurality of speeds are provided on the outer periphery of each shaft. And a transmission having a transmission that performs a shifting operation by meshing the gears with a synchromesh transmission mechanism to rotate a rotating drum having a cam groove for change formed on an outer peripheral surface near the transmission. The synchromesh transmission mechanism of the transmission, which is freely disposed and is operated following a change cam groove of the rotary drum when the rotary drum is rotated by a predetermined angle by a linear shift operation by a shift operation lever. Arrange the transmission shaft to operate and reverse A change cam groove of the rotary drum so that the speed change shaft can be operated so as to stop the main shaft by a synchronizing action of rotation by a change mechanism for the first to fifth speeds of the synchromesh speed change mechanism during a speed change. A transmission, wherein the transmission is formed.