JPS61270548A - Automatic v-belt transmission - Google Patents

Abstract

PURPOSE:To perform speed change efficiently by limiting relative rotation of movable half pulley against fixed half pulley thereby eliminating slippage of V-belt. CONSTITUTION:Upon application of load heavier than predetermined level onto a driven shaft 35, relative rotation is produced between the pulley guide collar 39 and fixed and movable pulley shafts 40, 43. Consequently, the fixed half pulley 42 and the movable half pulley 45 will never rotate relatively thus to move the movable half pulley 45 axially. As a result, V-belt 28 of V-pulley 36 will never slip resulting in smooth and highly efficient speed change.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a V-belt transmission type automatic transmission used in motorcycles and the like.

[Conventional technology]

This V-belt transmission type automatic transmission has a V-belt stretched between a V-pulley on the driving side and a V-pulley on the driven side, and each
■V on both sides of the belt on the opposite side of the V-groove of the V-shaped annular groove of the pulley
The rotation of the driving side is transmitted to the driven side by frictionally engaging the shaped inclined surfaces, and the interval between the V-shaped annular grooves of the V-pulleys is changed.The effective winding diameter of the V-belt for each V-pulley is determined. to achieve continuously variable speed.

As this speed change means, the way 1 is adjusted in proportion to the speed of the drive shaft.
- one that utilizes the centrifugal force acting on the
There is a device using a torque cam mechanism that operates according to the load on the driven shaft side, as shown in Japanese Patent No. 413. To explain this based on FIG. 1, there are bearings 2 and 3 on the outer circumference of the driven shaft 1. A cylindrical shaft-shaped pulley guide collar 4 is rotatably supported through the shaft, and a cylindrical shaft-shaped fixed pulley shaft 6 having a fixed pulley half 5 on the outer periphery of the pulley guide collar 4 is rotatably supported. Further, a cylindrical movable pulley shaft 8 having a movable pulley half 7 is fitted on the outer periphery of the fixed pulley q116 so as to be rotatable in the circumferential direction and movable in the axial direction. and the fixed pulley half 6 constitute a variable V-pulley 9 on the driven side.

Drive plates 1 to 10 are fixed to the outer end (left end in FIG. 1) of the pulley guide collar 4, and a coil spring 1 is installed between the drive plate 10 and the movable pulley shaft 8.
1 is compressed and urges the movable pulley half 7 to approach the fixed pulley half 5.

Further, the pulley guide collar 4 is formed with a cam groove 12 that has a long hole in the axial direction and is inclined in the circumferential direction, and the fixed pulley shaft 6 has a cam groove 13 that has a long hole in the axial direction. A torque cam pin 14 fixed to the movable pulley shaft 8 is engaged with the torque cam pin 12.13 via a guide roller 15.16.

A V-belt 17 for power transmission is stretched between the driving-side V-pulley (not shown) and the driven-side V-pulley 9.

With this configuration, the fixed pulley half 5 and the movable pulley half 7 rotate together, and when a load above a certain level is applied to the driven shaft 1, the fixed pulley half 5 and the movable pulley half 7 rotate together. The movable pulley half 7 moves only in the axial direction with respect to the fixed pulley half 5 by preventing relative rotation between Perform appropriate gear changes accordingly.

[Problem that the invention seeks to solve]

However, as described above, since it has a triple structure including the pulley guide collar, fixed fixed pulley shaft, and movable pulley shaft, the space in the radial direction is tight and the structure is complicated. Further, because of the triple structure, there is a possibility that the pulleys may run out due to the overlap of processing tolerances of each member, which will affect the durability of the V-belt.

Therefore, an object of the present invention is to improve the durability of the V-belt by preventing the V-pulley from wobbling with a simple structure.

[Means for solving problems]

In order to achieve the above object, the present invention provides variable V pulleys each consisting of a fixed pulley half and a movable pulley half, respectively disposed on a drive shaft and a driven shaft, and a V belt stretched between these V pulleys. (1) In a V-belt transmission type automatic transmission in which the effective winding diameter for the pulley can be changed, a pulley guide collar is rotatably supported on the outer periphery of at least one of the shafts, and the outer periphery of the pulley guide collar is rotatably supported. A fixed pulley shaft having a fixed pulley half is rotatably fitted to the pulley guide collar, and a movable pulley shaft having a movable pulley half is rotatably and movably fitted to the pulley guide collar. A first torque cam pin and a second torque cam pin are implanted, cam grooves are respectively formed in the fixed pulley shaft and the movable pulley shaft, and a first torque cam pin is installed in the pulley guide collar.
(・Insert the cam bin into the cam groove of the fixed pulley shaft, and
A torque cam mechanism is constructed by engaging torque cam pins with respective cam grooves of the movable pulley shaft.

[For production]

As a result, relative rotation of the movable pulley half with respect to the fixed pulley half is restricted and the movable pulley half moves only in the axial direction, and the winding diameter of the V-belt can be varied without slipping of the V-belt on the V-pulley.

[Example] An example of the present invention will be described based on FIGS. 2 and 3.

A drive-side variable diameter V-pulley 21 is installed on a drive shaft 20 connected to a drive source. This V-pulley 21 is composed of a fixed pulley half 22 and a movable pulley half 23. The fixed pulley half 22 is formed into a disk shape with a conical surface 24 on one surface and is fixed to the end of the drive shaft 20, and the movable pulley half 23 has a conical surface 25 on one surface and has a short cylindrical shape. A guide boss 26 formed and fixed to the drive shaft 20
The fixed pulley half-rest 22 and the movable pulley half 23 face each other to form a V-shaped annular groove 27, and a V-belt 28 is inserted into this annular groove 27. and is held between opposing conical surfaces 24° and 25.

A cover plate 29 is fixed to the end of the guide boss 26 on the back side of the movable pulley half 23, and a sealing material 30 is installed between the cover plate 29 and the back of the movable pulley half 23.
．． 31 forms a variable ratio hydraulic pressure chamber 32 which is sealed, a liquid chamber is sealed in this hydraulic pressure chamber 32, a pulley guide stroke bin 33 is provided on the cover plate 29, and a variable ratio hydraulic pressure chamber 32 is formed on the back surface of the movable pulley half body 23. The guide portion 34 is inserted into the guide portion 34.

As a result, the movable pulley half 23 approaches and separates from the fixed pulley half 22 by using the centrifugal hydraulic pressure load of the liquid 1- generated in accordance with the rotation of the V pulley 29.
The width of the annular groove 27 is varied, and the V pulley 21 is
The winding diameter of the belt 28 is changed.

The driven shaft 35 is provided with a driven side variable diameter V pulley 36 . This V pulley 36 has a bearing 37 on the outer periphery of the driven shaft 35.
．． 38, a cylindrical shaft-shaped pulley guide collar 39 rotatably supported via a cylindrical shaft-shaped fixed pulley shaft 40 rotatably fitted on the outer periphery of this pulley guide collar 39, and this fixed pulley shaft. A fixed pulley half 42 having a conical surface 41 fixed to the inner end of the fixed pulley shaft 40 (on the right side in FIG. 2), and the outer periphery of the pulley guide collar 39 on the outer end side of the fixed pulley shaft 40 (on the left side in FIG. 2) A movable pulley half 45 having a movable pulley shaft 43 fitted so as to be rotatable and movable in the axial direction, and a conical surface 44 fixed to the inner end of the movable pulley shaft 43 (on the right side in FIG. 2). The fixed pulley half 42 and the movable pulley half 45 face each other to form a V-shaped annular groove 46, and a V-shaped annular groove 46 is formed within this annular groove 46.
The belt 28 is inserted and held between the conical surfaces 41.4/l. As a result, the V-bell 1-28 is stretched between the variable diameter V-pulley 21 on the driving side and the variable diameter V-boo 936 on the driven side.

A first torque cam pin 47 and a second torque cam pin 48 are implanted in the pulley guide collar 39, and each rotatably supports a guide roller 49, 50.

Further, as shown in FIG. 3, the fixed pulley shaft 40 has a cam groove 51 with a long hole slightly inclined in the circumferential direction, and the movable pulley shaft 43 has a cam groove 52 with a long hole in the axial direction and inclined in the circumferential direction. are formed, respectively, and these cam grooves 51 and 52 are formed so as to be inclined so that one end of each of the cam grooves 51 and 52 approaches in the direction of rotation of the driven shaft 35.

The first torque cam pin 47 of the pulley guide collar 39 is inserted into the cam groove 51 of the fixed pulley shaft 40 via the guide roller 49, and the second torque cam pin 48 is inserted into the guide roller 5 via the guide roller 49.
0 respectively engage with the cam grooves 52 of the movable pulley shaft 43 to form a torque cam mechanism.

A cover 53 is fixed to the outer end (left side in FIGS. 2 and 3) of the pulley guide collar 39.
A coil = 11-spring 54 is compressed between the movable pulley shaft 43 and urges the movable pulley half 45 to approach the fixed pulley half 42. A centrifugal clutch mechanism 55 is provided on the right side in FIGS. 2 and 3.

Next, to explain the operation of the automatic transmission configured in this way, when the rotation of the drive shaft 20 is low, the interval between the V-shaped annular grooves 27 of the drive side movable diameter V pulley 21 widens, while the driven side variable Since the movable pulley half 45 of the diameter V pulley 36 is biased toward the fixed pulley half 42 by the spring 54, the interval between the ■-shaped annular grooves 46 is narrow, so that the V of the drive side V pulley 21 The belt winding diameter is small, the driven side winding diameter is kept large, and the driven shaft 3
5's rotation is decelerated and its rotational torque is amplified.

As the rotation of the drive shaft 20 increases, the centrifugal hydraulic pressure load of the liquid l- sealed in the variable ratio hydraulic pressure chamber 32 formed on the back surface of the movable pulley half 23 of the drive side V pulley 21 increases, and the movable pulley half 23 of the drive side V pulley 21 becomes movable. The pulley half 23 is moved closer to the fixed pulley half 22, the interval between the V-shaped annular grooves 27 is narrowed, and the winding #l) diameter of the V-belt 28 is increased, whereby the movable pulley half of the driven side V-pulley 36 is 45 moves away from the fixed pulley half 42 against the force of the spring 54, the interval between the ■-shaped annular grooves/I6 becomes wider, the winding diameter of the V-belt 28 is reduced, and the rotation speed of the driven shaft 35 is increased.

In this accelerated rotation state of the driven shaft 35, if a load above a certain level is applied to the driven shaft 35, this load is applied to the centrifugal clutch mechanism 55. A force is applied in the circumferential direction to the first torque cam pin 47 and the 21st to 48th torque cam pins 48 through the boule guide collar 39, thereby causing the 11th torque cam pin 47 to
The twenty-first to second cam pins 48 move along the cam grooves 51 of the fixed pulley shaft 40 and the cam grooves 52 of the movable pulley shaft 43.

Here, the cam Fi 52 of the movable pulley shaft/13 is deeply inclined in the circumferential direction with respect to the cam groove 51 of the fixed pulley shaft 40, and the cam 52 is deeply inclined in the circumferential direction with respect to the cam groove 51 of the fixed pulley shaft 40. Since the movable pulley shaft 43 is formed to approach the fixed pulley shaft 40 in the axial direction, the movable pulley half 45 approaches the fixed pulley half 42 and moves toward the fixed pulley shaft 40. The interval between the annular grooves 46 is narrowed to increase the winding diameter of the V-bells 1 to 28 on the driven side V pulley 36, and conversely, the winding diameter of the V belt 28 on the driving side V pulley 21 is made smaller. The desired torque is obtained by decelerating the rotation of the driven shaft 35 and amplifying the torque.

That is, when a load above a certain level is applied to the driven shaft 35,
Relative rotation is performed between the pulley guide collar 39 and the fixed pulley shaft 40 and the movable pulley shaft 43, and the movable pulley half 45 does not rotate relative to the fixed pulley half 42 and the movable pulley half 45. Move in the axial direction. This prevents the V-belt 28 from slipping on the V-pulley 36, allowing smooth and efficient gear shifting.

Further, the fixed pulley shaft 40, the movable pulley shaft 43, and the pulley guide collar 39 have a double structure, and the first torque cam pin 47 and the 21st torque cam pin 48 respectively.
Since the pulley guide collar 39 is engaged with the pulley guide collar 39, the structure is simpler than the conventional one, there are fewer processing tolerances, and the occurrence of runout of the V-pulley can be prevented.

In the above embodiment, the torque cam mechanism is provided on the driven shaft side, but it may be provided on the drive shaft side or on both the drive shaft and the driven shaft.

〔Effect of the invention〕

As described above, the present invention includes variable V pulleys each consisting of a fixed pulley half and a movable pulley half, arranged on a drive shaft and a driven wheel, respectively, and a V belt stretched between these two V pulleys. In a V-belt transmission type automatic transmission in which the effective winding diameter for the V-pulley can be changed, a pulley guide collar is rotatably supported on the outer periphery of at least one of the shafts, and fixed to the outer periphery of the pulley guide collar. A fixed pulley shaft having a half pulley rest is rotatably fitted, and a movable pulley shaft having a movable pulley half is rotatably and movably fitted in the axial direction, and eleventh to A Luc cam pin and 21st ~ Luc cam pins are implanted, cam grooves are formed in the fixed pulley shaft and the movable pulley shaft, respectively, and 11th~ Luc cam pins of the pulley guide collar are installed in the cam grooves of the fixed pulley shaft. The two torque cam pins are respectively engaged with the cam grooves of the movable pulley shaft to form a torque cam mechanism, so slippage between the pulley and belt is effectively prevented with a simpler structure than before, allowing smooth and efficient shifting. In addition, the durability of the V-belt can be improved without causing the pulley to run out.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an automatic transmission equipped with a conventional torque cam mechanism, Figs. 2 and 3 show an embodiment of the present invention, and Fig. 2 is a sectional view of a V-belt transmission type automatic transmission. Figure, 3rd
The figure is a partial sectional view showing the torque cam mechanism of the driven side V-pulley.

Claims (1)

[Claims] 1. Variable V consisting of a fixed pulley half and a movable pulley half
In a V-belt transmission type automatic transmission in which pulleys are respectively disposed on the driving shaft and the driven shaft, and the effective winding diameter of the V-belt stretched between the two V-pulleys can be changed for each V-pulley, A pulley guide collar is rotatably supported on the outer periphery of at least one of the shafts, a fixed pulley shaft having a fixed pulley half is rotatably fitted on the outer periphery of the pulley guide collar, and a movable pulley half is provided. A movable pulley shaft having a movable pulley shaft is rotatably and movably fitted in the axial direction, a first torque cam pin and a second torque cam pin are implanted in the pulley guide collar, and the movable pulley shaft is connected to the fixed pulley shaft and the movable pulley shaft. A torque cam mechanism is configured by forming cam grooves, respectively, and engaging a first torque cam pin of the pulley guide collar with the cam groove of the fixed pulley shaft and a second torque cam pin with the cam groove of the movable pulley shaft. A V-belt transmission type automatic transmission featuring: