JPS591848A - Motorcycle transmission mechanism - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a transmission mechanism for automatic motorcycles.

Conventionally, in the transmission mechanism of a two-wheeled motor vehicle, the transmission mechanism is accommodated in the narrowest possible space between the change drum and the shift shaft, reducing the space required in a plane perpendicular to the shift shaft, and connecting the output shaft and kick shaft. It is desired to shorten the axial length of the transmission (the longitudinal width of the change drum) to avoid interference between the transmission and the change drum.

As a further improvement, for example, the structure shown in Fig. 1 has already been proposed7, (Utility Application No. 56-64952) b
In FIG. 1, a shift shaft 3 is disposed in the crankcase l at a distance in parallel with the υ;L change drum 2 and the change drum 2, and the shift shaft 8 has a
(not shown) is fixed. The shift arm 4 welded to the shift shaft 8 protrudes from the shift shaft 8 toward the change drum 2 in a plane perpendicular to the shift shaft 8, and is integrally connected to the holder plate 5 at a constant interval via a rivet. are doing. Shift arm 4 and holder plate 5
A shift port /1/6 is inserted into the gap so as to be slidable only in the radial direction of the shift shaft 30, and the shift port /1/6 is always urged toward the change drum 2 by a coil spring 7. A pair of shift pawls 8.8 at the tip of the shift ball lv6 are in a position where, when in neutral, they sandwich two of the drum pins 9 arranged at equal intervals on the circumference on the end face of the change drum 2, with a gap between them. When the change pedal attached to 8 is kicked up, the stopper surface 10 on the side opposite K collides with the catch seat 11 in the crankcase 1, and rotation of the shift shaft 3 is prevented.

However, the change drum 2 tries to continue to rotate after rotating by one step due to inertia force, but at this time, the following drum pin 9 collides with the lower cam surface 14, and the rotation is stopped. The same thing happens when you press the change pedal.
The shift port/L/6 collides with the lower seat 15 and aligns with the following drum pin 9 to prevent over-rotation. The catch seat 15 is also formed integrally with the crankcase IK.

However, when the following drum pin 9 collides with the cam surface 14 and its rotation is stopped, a force perpendicular to the cam surface 14 is applied to the shift port/I/6 due to this collision, and a component of that force is applied to the shift port/I/6. Therefore, shift port/l/6 is shift axis s
Although it is pushed in the side direction, the reaction force and frictional force at the pressure contact between the shift port /I/6 and the catch seat 11 cause the shift port /L/
(Since i does not move toward the side of the shift shaft 8, the shape of the one stopper surface 10 and the catch seat 11 must be determined.Also, the change drum 2 must be rotated by one step, and the change pedal can be released from the state. When L/6 is returned to the neutral position by the elasticity of the return spring 16, the cam surface 14 receives a reaction force from the drum pin 9, and the shift port/l/6 moves toward the shift shaft 8 side against the elasticity of the barb 7. The angle of the cam surface 14 must be determined so that it can be retracted.

That is, as is clear from the above explanation, in order to prevent over-rotation of the change drum 2, the shift pole 6 must not slide, and on the other hand, in order to return the shift pole μ6 to the neutral position, it must be retracted from the drum pin 9. Therefore, the angle of the cam surface 14 and the positional relationship between the foot surface 10 and the catch seat 11 must be changed. Regarding the angle, if a strict ('^ degree is required), it will be difficult. However, the catch 1
1.15 is provided integrally with the crankcase 1 which is usually manufactured by f7I4 construction]1. Because of this, it was difficult to determine the exact position and angle.

In view of the above-mentioned conventional problems, the present invention accommodates the transmission mechanism in the narrowest possible space between the change drum and the shift shaft, reduces the required clearance in a plane perpendicular to the shift shaft, and reduces the space between the output shaft and the shift shaft. It satisfies the conventional requirement (7) of shortening the axial length of the transmission and the longitudinal width of the change drum by avoiding interference with the kick shaft, and is easy to manufacture and reliably prevents over-rotation of the change drum. The aim is to provide a gear shifting mechanism that prevents this from occurring.A hole is provided in the shift port /L/, and abutments facing the shift shaft are provided on both edges of the window in the rotating direction. 1. The hook pin is made to protrude so that when the change drum over-rotates, the hook pin comes into contact with the abutment surface facing the shift shaft and prevents the shift pole from sliding toward the shift shaft. It is characterized by

FIG. 2 is a longitudinal sectional side view showing the transmission mechanism according to the present invention, and FIG. 3 is a partial sectional view taken along the line -■ in FIG. 2, with arrow F pointing forward. Inside the crankcase 21, a change drum 22 and a -C shift shaft 23 are arranged parallel to and spaced apart from the change drum 22, and a shift beder /L/ (not shown) is fixed to the shift shaft 231. The shift arm 25, which is welded to the shift shaft 2B, protrudes from the shift shaft 23 toward the change door 22 side within a plane that is curved and square with the shift piece 123, and is fitted into two rivets 26.27 and both rivets 26.27. Washers 80, 81 (FIG. 8) are rigidly connected at regular intervals by ring-shaped spacers 28, 29. The central cylindrical portion 84 of the return spring 88 fits into the cup 82 on the shift shaft 2B.
The parallel portions 35, 86 at both ends of the spring 330 are located in a plane parallel to the shift arm 25 at a position close to the shift arm 25 (FIG. 3). The tips of the parallel portions 35 and 36 are pressed against the cylindrical surface of the stop bin 37 (hanging pin) fixed to the Kufunku case 21 on both sides, and the stop bin 3
A portion closer to the shift shaft 28 than 7 grips a collar 88 (FIG. 3) on the rivet 26.

On the other hand, a shift port (VB9) is inserted into the gap between the shift arm 25 and the washer 80.31 (Fig. 3).
The radially long notches 40.41 of the shift shaft 23 provided in the shift pole/L/39 fit into the corresponding even spacers 28.29, so that the shift pole 39 is connected to the shift arm 25 and the washer 80.31. The shift shaft 80 is slidable along arrows A and A' in the radial direction with respect to the inner surface facing the shift shaft 80 . shift shaft) VB2 shift shaft 23
A long hole 24 provided in the side edge 42 and the shift arm 25
As is clear from FIG.
is always on the change drum 22 side (in the direction of the arrow). A pair of shift buttons 44 (engaging claws) are provided at the end of the shift port/l/89 on the change drum 22 side, sandwiching the open end of the notch 41. Behind the shift ports 44, the shift shaft 28 is provided. It is provided with cam surfaces 45, 45 which gradually move away from each other towards the sides. The pair of shift buttons 44, 44, when in neutral, are positioned to sandwich two drum pins 47, 47a on the shift shaft 28 side of the drum pins 47, which are arranged on the end surface of the change drum 2 at equal intervals on the circumference, at a distance. Further, a window 48 is provided approximately at the center of the shift bow/l/89, and concave portions are formed at both end edges 49.50 in the rotational direction of the window 48, and concave portions 51.52 are formed at both ends of the window 48 in the rotational direction. is provided. A notch 40 is opened at the edge of the window 48 on the shift shaft 23 side. Also, as shown in FIG. 8, a stop pin 87 (hanging pin) is fitted inside the window 48.

Both 58 and 541d have bell crank-shaped lock levers,
The central part is rotatably supported by a support shaft 55, and the lock lever
One end of 53 is connected to the inner surface of case 721 via tension spring 56) 57 K contact M1. ．． The arcuate pressing surface 58 on the 1M side presses against the adjacent drum pin 47.47. hand,
The rotation of the change drum 22 is prevented and moderation is learned.

One end of the lock lever 54 is connected to one end of the lock lever 58 via a tension spring 59, and a roller 60 at the other end is pressed against a guide member 61 of the change drum 22.

Next, the production wJS will be explained. First, in Fig. 2, when the shift shaft 3 is rotated in the direction of arrow B by kicking up the change beder /L/ (not shown) attached to the shift shaft 23 with your foot (Fig. 4), the lower shift button 44 hooks the drum pin 47a and rotates the change drum 22 by one step in the direction C (FIG. 5). Then, just when the change drum 22 rotates by one step, the end surface 50 of the window 48 touches the stop bin 3.
Collision 1 occurs at 7, and rotation of the shift shaft 23 in the direction of arrow B is prevented. Since the change drum 22 has inertia, it rotates by several minutes. 1. If you continue to move in the direction of arrow C even after 1. (Fig. 6), the following drum pin 471) collides with the lower cam surface 45 and the cam surface 4 hits the shift bow/l/89.
Apply a force P1 perpendicular to 5. and the center line x1 of force P1
Due to component force P2 parallel to
However, the abutting surface 52 provided on the window 48 comes into contact with the via 37 (FIG. 7), preventing the shift ball 39 from moving in the direction of arrow A', thereby preventing the change drum 22 from overloading. Rotation is protected +l. Further, the change drum 22 is returned to the state shown in FIG. 5 by the force of the lock lever 58 and the tension spring 56,59. Next, when the change pedal is released, the shift bow/1/R9 is returned in the direction of the arrow B' by the elastic force of the return spring 88 (FIG. 2) (FIG. 8). The angle of the cam surface 45 is determined so that the cam surface 45 receives a reaction force from the drum pin 47b, resists the elasticity of the spring 48 (FIG. 3), and allows the shift bow (VB9) to retreat in the direction of arrow A'. Spring spring R
From RK, the transmission mechanism returns to the neutral position and returns to the state shown in Fig. 2, but the change drum 22 remains rotated by one step compared to the state before operation (ftf, K is maintained)1
．． Ru.

The same is true when the change pedal is depressed, and the two side edges 45) of the window 48 and the hit 1.1Ji51 form a flange that prevents the change tram 22 from overshooting i1i.

As explained above, in the present invention, the window 48 is provided in the shift bow/I/89, and the shift axis 2B'' (the opposing contact point 51. 52 is provided, the catch bin 37 (stop bin) is protruded into the window 48, and the change tram 22 is moved for one step until it hits the catch bin 87 at the over-rotated position.
1.52 comes into contact with K (~) to prevent the shift ball from sliding onto the shift shaft 23. Therefore, the change drum 22 is prevented from over-rotating, and the change tram 22 and shift shaft 23 are prevented from over-rotating.
By accommodating the transmission mechanism in the narrowest possible space between the transmissions, reducing the space required within the curve perpendicular to the shift shaft 28, and avoiding interference with the output shaft and kick shaft, the change tram can be made longer in the axial direction of the transmission. The conventional requirement of reducing the width of the longitudinal force surface of 22 can be satisfied.

Furthermore, compared to the conventional structure shown in Fig. 1, the crankcase 21, which is a large-sized cast product, does not require the catch 11. It hits the shift ball 39 that can be processed into 51.5
Viewing 2 - 1 Since this is done, there is an advantage that the manufacturing process can be simplified and costs can be reduced. In addition, a window 48 is provided in the shift ball 89, and the hook bottle 37, which is a slightly extended version of the conventional hook bottle, is protruded from inside the nitrogen 48. This is an advantage of the present invention.

[Brief explanation of drawings]

Fig. 1 is a side view of a conventional transmission mechanism, Fig. 2d is a vertical sectional side view of a transmission mechanism according to the present invention, Fig. 31 is a partial cross-sectional view of Fig. 2, and Figs. Explanatory diagram 6 21
...Case, 22...Change tram, 2B...
Shift shaft, 25... Shift arm, 38... Return spring, 37... Hanging bottle, 39... Shift ball, 4B... Arc-shaped spring (A; 1-force rock structure), 44...
...Engaging claw, 47.47a, 471)...Drum bin, ゛48...Feeling, 49.50...Edge, 51.52
...Touch surface Figure 3

Claims (1)

[Claims] A shift shaft supported by a case and connected to a shift pedal, a shift arm fixed to the shift shaft, and a pair of engagement pieces connected to the shift arm so as to be slidable only in the radial direction of the shift shaft and at the tip. A shift pole with a claw, a change drum with a drum pin on the side facing the engagement claw of the shift pole p, a biasing mechanism that biases the shift pole against the drum (1111), and a return that returns the shift arm to the neutral position. A contact surface is provided that extends from the spring and a return spring hook pin supported by the case between the shift shaft and the drum, and the hook pin is made to protrude within the window so that the hook bin shifts when the change drum over-rotates. 1. A two-wheeled motor vehicle shifting mechanism that prevents over-rotation of a change drum by contacting a contact surface facing the shaft and preventing the shift pole from sliding toward the shift shaft. mechanism.