JPS6360261B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a change device for a two-wheeled motor vehicle.

Generally, a change device for a motorcycle is equipped with a plurality of drive pins 2 spaced at equal intervals in the circumferential direction on the end face of a change drum 1, as shown in FIG.
A shift arm 4 interlocked with a change pedal 3 rotates the change drum 1 via the pin 2. As the change drum 1 rotates, each shift fork 7 is moved in the axial direction via the cam groove 5 and pin 6 of the drum 1, and each change gear 50, 51, 52 (Figs. 7 and 8) is moved in the axial direction. do.

However, after many years of use, the meshing pawls 53, 54, and 55 of the chain gear (Figs. 7 and 8)
A large thrust load is applied to the chain gear due to factors such as wear and vibration of the motorcycle itself, and this thrust load causes the chain gear 50,
51, 52 and the shift fork 7 move toward the neutral position, the drum 1 also rotates due to the cam action, and the engaging pawls 53, 5 of the change gear
A problem occurs in which the meshes 4 and 55 become disengaged. 7 and 8 is a groove into which the shift fork 7 shown in FIG. 1 is fitted.

The conventional device is equipped with a positioner consisting of, for example, a cam 9 (FIG. 1) and a ball 10 that is biased by a spring or the like on the cam 9.
The drum 1 can be held at a predetermined rotational position by the elastic force of the spring, but the change gears 50, 51, 5 cannot be moved by the elastic force of the spring alone.
It was not possible to prevent the drum 1 from rotating due to the thrust load No. 2. (Jikkoaki as prior art)
There is No. 53-25333. ) In addition, as in Utility Model Publication No. 52-25777, a complex-shaped clamp lever with a fork is rotatably provided, and the fork (groove portion) at the tip of the clamp lever is engaged with one drive pin to control the rotation of the drum. Some have a structure that stops them. However, since the shape of the lever is complicated, manufacturing, assembly, and adjustment are time consuming, and since only the tip of the lever engages only one drive pin, looseness may remain.

The present invention includes a drum lock mechanism capable of locking the change drum 1 unrotatably by a drum stopper that can freely protrude between drive pins. Interlockingly connected to the operating section, the rotation of the drum is reliably prevented during non-change operation, and the meshing pawls 53, 5 of the change gear
This is to prevent the meshes 4 and 55 from becoming disengaged. It is also an object of the present invention to provide a locking mechanism that is simple in structure and free from rattling.
The present invention will be explained below based on the drawings.

In FIG. 2 (arrow F points forward), the change shaft 11 is rotatably supported by a transmission case (not shown), and a pedal arm 12 and a change plate 13 are fixed to the change shaft 11. . The pedal arm 12 extends forward and upward, and is provided with a change pedal 3 at its front end. The change plate 13 extends forward and has a rotation amount regulating hole 15 in the middle thereof, and a return spring locking portion 16 in the regulating hole 15 portion. A pin 17 fixed to the transmission case is inserted into the center of the regulation hole 15, and the pin 17 is held between extensions 18a at both ends of a return spring 18 which is fitted and supported by the change shaft 11. The spring locking portion 16 is bent toward the back side with respect to the paper surface of FIG.
It is sandwiched by both end extensions 18a. That is, the change plate 13 is connected to both circumferential ends of the regulating hole 15 around the change shaft 11 and the pin 17 in the direction indicated by the arrow A.
The amount of rotation in the direction of arrow B is regulated, and the return spring 18 returns to the position shown in FIG.

A shift arm 4 and an overshift stopper 22 are rotatably supported at the front end of the change plate 13 via pins 20, respectively.
The arm 4 and the stopper 22 are biased in the directions of arrow C and arrow D, respectively, by a coiled spring 25.

The change drum 1 includes, for example, six parallel drive pins 2 spaced apart at equal intervals in the circumferential direction, and is rotatably supported by a mission case.
The aforementioned shift arm 4 is in contact with the two drive pins 2 on the front side, and the overshift stopper 22 is in contact with the two drive pins 2 on the rear side. First and second claw portions 26 and 27 are formed at the upper end and middle portion of the shift arm 4 and project rearward.
They face each other with an interval L ₁ in the vertical direction. First and second stopper pawls 28 and 29 are formed at the upper end and middle portion of the overshift stopper 22 and project forward. They face each other from above with an interval of L ₂ + L ₁ between them.
In addition, the second stopper pawl 29 is connected to the drive pin 2 on the lower rear side.
They face each other from below with an interval of L ₂ +L ₁ between them.

The locking mechanism 30 that can lock the change drum 1 non-rotatably includes a drum stopper 31 in the form of a band plate.
, a stopper guide body 32, a guide body cover 33, a biasing spring 34, and the like.

The stopper guide body 32 has a guide groove 37 (FIG. 6) with a U-shaped cross section that extends in the front-rear direction, and the bolt 35 (FIG. 2) together with the cover 33.
It is fixed to the transmission case by a screw. The drum stopper 31 is inserted into the guide groove 37 so as to be slidable in the front-rear direction, extends forward toward the center of the drum 1, and can be inserted between the two drive pins 2 on the rear side. The vertical width of the drum stopper 31 is such that both the upper and lower edges of the drum stopper 31 can come into sliding contact with the two rear drive pins 2, and the front edge of the drum stopper 31 has a circular shape that projects forward. It is formed in an arc shape and smoothly connects to the upper and lower edges.

As shown in FIG. 5, the biasing spring 34 is tensioned between the rear bent portion 31a of the drum stopper 31 and the bent portion 33a of the cover 33, and biases the drum stopper 31 forward. are doing.

A pin 40 parallel to the drive pin 2 is fixed to the drum stopper 31 (FIG. 2), and this pin 40 abuts the rear edge of the overshift stopper 22, while First and second cams 41 and 42 for moving the drum stopper 31 rearward are formed on the end edge in a rearwardly protruding shape. First and second cams 41, 42
are located above and below the pin 40, respectively, as shown in FIG. 2, when the change pedal 3 is not operated.

Next, the operation will be explained with reference to FIGS. 2 to 4. When the change operation is not being performed, the drum stopper 31 protrudes between the two rear drive pins 2, as shown in FIG.
is firmly locked so that it cannot be rotated.

When the change pedal 3 is started to be depressed for downshifting, the shift arm 4 and overshift stopper 22 begin to descend via the change shaft 11, change plate 13, and pin 20. When the shift arm 4 and overshift stopper 22 descend a distance of _L1 , the drum stopper 31 is moved rearward by the first cam 41 via the pin 40, as shown in FIG. 3, and the locked state is released. Also, the first claw portion 26 of the shift arm 4 comes into contact with the drive pin 2 on the upper front side.

When the change pedal 3 is further depressed as shown in FIG. 3, the change drum 1 together with the shift arm 4 rotates 60 degrees in the direction of arrow W, and a downshift is performed. . When the drum 1 rotates 60 degrees, the first stopper pawl 28 of the overshift stopper 22 prevents the change drum 1 from rotating in the direction of arrow W, as shown in FIG. In the state shown in FIG. 4, the pin 40 has climbed over the first cam 41 and protrudes between the drive pins 2. Note that the pin 40 passes over the first cam 41 on the way from FIG. 3 to FIG. When the stopper 31 is rotated to the position shown in FIG. 4, it projects between the drive pins 2.

After the downshift is completed, the shift arm 4, overshift stopper 22, and change plate 13 return to the state shown in FIG. 2 due to the action of the return spring 18.

To shift up, press change pedal 3.
Push up from the position shown in Figure 2 and change the drum 1.
Shift arm 4 is rotated in the opposite direction of arrow W.
Since the operations are basically the same as those for downshifting, detailed explanations will be omitted. However, in the case of upshifting, the second claw part 27 and the second stopper claw 29 act on the drive pin 2 instead of the first claw part 26 and the first stopper claw 28.

As explained above, the present invention includes a plurality of drive pins 2 on the end surface of the change drum 1, which are parallel to the axis of the change drum 1 and equally spaced apart in the circumferential direction, and which are connected to the change pedal 3 for shifting. A drum locking mechanism 30 is provided which allows the change drum 1 to be freely rotated by the arm 4 via the drive pin 2, and which can lock the change drum 1 unrotatably by a drum stopper 31 that can freely protrude between the drive pins 2.
A drum lock mechanism 30 is configured to release the lock at the start of the change operation and lock it at the end of the change operation.
is interlocked with a change operation section, for example, change pedal 3, through an interlocking mechanism consisting of cams 41, 42, pin 40, etc., so that rotation of change drum 1 is reliably and firmly prevented during non-change operation. It is possible to change gears 52, 50,
51 interlocking claws 53, 54, 55 (7th, 8th
The pawls 53, 54, and 55 of the change gear will not become disengaged due to wear (see Figure) or vibration of the vehicle body.

Also, in the past, the pawls 53, 54, 5 of the chain gear
In order to prevent the gears 5 from coming out of engagement, some chain gear pawls 53, 54, 55 are formed with a reverse taper as shown in Fig. 10, but the machining of the pawls 53, 54, 55 is It was very time consuming. In contrast, in the present invention, the chain gears 50, 51, 52 and the pawls 53, 54, 55 themselves do not need to be processed at all, so manufacturing is easy.

Further, the stopper 31 of the locking mechanism 30 is made to be movable in a linear direction toward the center of the drum, and the width of the stopper 31 is set to be such that it can slide on both of two adjacent drive pins 2 when it enters between the drive pins 2. Therefore, when locking, the stopper 31 tightly contacts and pinches both drive pins 2, and compared to the conventional fork type that engages with one drive pin, there is less rattling of the drum 1 and the locking performance is improved. Are better.

Furthermore, since the stopper 31 is movable in a straight line toward the center of the drum, the stopper 31 has a simple shape and is easier to manufacture than the conventional fork type.

In the embodiments shown in FIGS. 2 to 6, the cams 41, 42
Although a cam mechanism including a pin 40 and the like is provided as the interlocking mechanism, a solenoid that operates in response to the stroke of the change pedal 3 may also be provided as the interlocking mechanism.

Further, a clutch lever can also be used as a change operation unit that is interlocked with the lock mechanism. That is, the lock is released at the start of the clutch disengagement operation, and locked at the end of the clutch engagement operation.

Further, the present invention can be applied to small three-wheeled motor vehicles and the like as long as the vehicle is equipped with a change device having a change drum.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional example, and FIGS. 2 to 4 are side views of a change device according to the present invention, in which FIG. 2 is a state during non-change operation, and FIG. 3 is a state at the start of change operation. , Fig. 4 shows the state at the end of the change operation, Fig. 5 is a partial cross-sectional view of Fig. 2, Fig. 6 is a cross-sectional view of Fig. 5, and Fig. 7 is a longitudinal side view of a general change gear device. 8 is a perspective view of FIG. 7, FIG. 9 is a sectional view of a general interlocking pawl, and FIG. 10 is a sectional view of a reverse tapered interlocking pawl. 1... Change drum, 2... Drive pin, 3...
...Change pedal (an example of a change operation part), 4
...Shift arm, 31, 32, 33, 34...
Drum stopper, guide body, cover, urging spring (drum lock mechanism), 40, 41, 42...pin, first cam, second cam (an example of interlocking mechanism).

Claims (1)

[Claims] 1 The end face of the change drum is equipped with multiple drive pins that are parallel to the axis of the change drum and equally spaced in the circumferential direction, and the change drum is rotated via the drive pins by a shift arm linked to the change pedal. A drum lock mechanism is provided which can lock the change drum unrotatably with a drum stopper that can freely protrude between the drive pins, and the stopper of the locking mechanism can be moved in a linear direction toward the center of the drum, and the width of the stopper can be changed. The drum lock mechanism is set to have a width that allows it to slide into contact with both two adjacent drive pins when it enters between the drive pins, and a drum lock mechanism is connected to the change investigation department via an interlocking mechanism so that it is unlocked at the start of the change operation and locked at the end of the change operation. A change device for a motorcycle, etc., characterized by being interlocked.