JP2583495Y2 - Torque cam for continuously variable transmission - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a continuously variable transmission, and more particularly to an improvement of a torque cam in a continuously variable transmission.

[0002]

2. Description of the Related Art A movable pulley sheave in an output pulley sheave of a continuously variable transmission of this type slides on an output sheave shaft during gear shifting. At this time, a torque cam is used to apply tension to a belt. This torque cam has a structure in which rollers roll on the cam surface,
There has been a problem that a tapping motion is generated between the cam surface and the roller due to the vibration of the torque cam generated at the time of gear shifting, and the cam surface is severely worn.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and has a torque cam of a continuously variable transmission capable of reducing a tapping force and reducing abrasion of a cam surface. The gist of the invention is to provide a winding between a pair of detachable input pulley sheaves attached to the input sheave shaft and a pair of detachable output pulley sheaves attached to the output sheave shaft. The rotation of the input sheave shaft is steplessly changed and transmitted to the output sheave shaft by the hung belt, and the output pulley sheave is attached to the fixed pulley sheave in the output pulley sheave in order to apply tension to the belt. Any one of the outer surface of the biased movable pulley sheave and a fixing member fixed to the output sheave shaft so as to face the outer surface is coaxial with the output sheave shaft. Cam surface is formed over the entire circumference,
On the other side, a torque cam mechanism having a roller that rolls on the cam surface is provided, and the roller has an outward direction.
The outer peripheral surface is formed in a tapered shape so as to receive the force
At the same time, it is stopped by bolts via the elastic plate.

[0004]

[Function] The roller that rolls on the cam surface in the torque cam mechanism is stopped by a bolt via an elastic plate. When vibration occurs in the torque cam and a tapping force is generated between the cam surface and the roller, the tapping force is used. The roller receives a force in the outward pulling direction, and this force is absorbed by the elastic plate, so that the striking movement force is reduced by the elastic plate, and wear due to the striking movement between the cam surface and the roller is reduced, and the cam surface is reduced. Is reduced.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 is a schematic configuration diagram of a continuously variable transmission, FIG. 2 is an enlarged sectional view of a torque cam mechanism, FIG. 3 is a perspective view of an assembled state of the torque cam mechanism, and FIG. FIG. 3 is an exploded perspective view of FIG.

In the continuously variable transmission shown in FIG. 1, an output shaft 1 of a prime mover E such as an engine is connected to a coaxial main drive shaft 3 via a clutch 2. An input sheave shaft 5 is coaxially disposed in front of the main drive shaft 3 via a bearing 4. On the side of the main drive shaft 3 and the input sheave shaft 5, a shaft 7 of a synchro coupling 6 for switching between forward and backward is installed in parallel, and a counter driven gear 8 fixed to the shaft 7 is fixed to the main drive shaft 3. With the driven main drive gear 9. The forward counter gear 10 and the reverse counter gear 11 to which the rotation of the shaft 7 is transmitted are loosely fitted to the shaft 7 of the synchro coupling 6 at the time of switching to the forward side and at the time of switching to the reverse side. The forward counter gear 10 meshes with a first sheave shaft gear 12 fixed to the rear of the input sheave shaft 5, while the reverse counter gear 11 meshes with a second sheave shaft gear 13 fixed to an intermediate portion of the input sheave shaft 5. And the idler gear 14 meshing with the idler gear 14. In front of the input sheave shaft 5, an input fixed sheave 15 fixed to the input sheave shaft 5 or
A sheave position adjusting device 17 for adjusting the axial position of an input movable sheave 16 slidably mounted in the input sheave shaft 5 in the axial direction is provided.

On the other hand, on the side of the input sheave shaft 5, an output sheave shaft 18 is disposed in parallel with the input sheave shaft 5.
The output sheave shaft 18 is provided with an output fixed sheave 19 fixed to the output sheave shaft 18 and an output movable sheave 20 loosely fitted to the output sheave shaft 18 so as to be slidable in the axial direction. Input fixed sheave 15 and input movable sheave 1
6 has a conical surface on the opposite side, and has a V-shaped groove 2 between them.
1 are formed, and the two constitute an input sheave 22. Similarly, the fixed output sheave 19 and the movable output sheave 20 have a conical surface on the opposite side, form a V-shaped groove 23 therebetween, and constitute an output sheave 24. A V-belt 25 is wound between the input sheave 22 and the output sheave 24, and the width of the V-shaped groove 21 is changed by adjusting the position of the input movable sheave 16 by the sheave position adjusting device 17. The speed ratio of the rotation of the output sheave shaft 18 to the rotation of the input sheave shaft 5 can be changed steplessly.

An intermediate shaft 26 is provided between the input sheave shaft 5 and the output sheave shaft 18, and a two-way differential clutch 27 is mounted on the intermediate shaft 26. This 2
Although the detailed description of the two-way differential clutch 27 is omitted, the power transmission to the output sheave shaft 18 is simply described in accordance with the operating state, the path passing through the two-way differential clutch 27 and the two sheaves 22. , 24, the driving force and the accelerating force are increased.
It serves to reduce the load applied to the belt 25.

The output sheave shaft 18 has a differential pinion 2
8 is fixed, the differential pinion 28 meshes with a differential idler gear 29, and the differential idler gear 29 meshes with a differential gear 31 of a differential device 30. 3
Reference numeral 2 denotes a computer including a microprocessor, an input sheave rotation speed sensor 33 for detecting the rotation speed of the input sheave 22, an output sheave rotation speed sensor for detecting the rotation speed of the output sheave 24, and an input sheave 2
Signals from a sheave position detection sensor 35 for detecting the position of the movable sheave 16 of the second and a shift position sensor (not shown) of the selector 36 are input, and the computer 32 receives the signals from the sheave position adjusting device 1 based on these signals.
7, the input sheave 22 is adjusted to a groove width suitable for the operation state.

Incidentally, the output sheave 24 is provided with a torque cam mechanism for keeping the V-belt 25 in tension at all times even when shifting. That is, a ring-shaped torque cam 37 is attached to the outer side surface of the output movable sheave 20 of the output sheave 24 concentrically with the output movable sheave 20 by bolts or the like. A cam surface 38 as shown in FIGS. 3 and 4 is formed on the outer surface of the torque cam 37. The cam surface 38 is formed by equally dividing the outer surface of the torque cam 37 into three parts, each having the same shape. The cam surface has undulations. Each cam surface 38 is a tapered surface that rises in gradient from the outer peripheral side to the inner peripheral side.

On the other hand, a roller hub 39 is fixed to the output sheave shaft 18 so as to face the torque cam 37. The roller hub 39 is formed in a cylindrical shape whose side facing the output movable sheave 20 is open, and one side of a spring 40 acting in a direction of pressing the output movable sheave 20 against the output fixed sheave 19 is provided inside the cylindrical portion. It is stored. On the outer surface of the cylindrical portion of the roller hub 39, three bosses 41 shown in the figure are integrally formed so as to protrude in the radial direction at equal angles. A roller 42 is fitted in each boss 41 so as to freely rotate.
Are secured by bolts 43 screwed in from the upper end surfaces. An elastic plate 45 made of an elastic material such as rubber, a disc spring, or resin is interposed between the bolt 43 and the upper surface of the roller 42. In addition, each roller 4
The outer peripheral surface 2 is formed to be compatible with the cam surface 38 of the torque cam 37.

Next, the operation of the continuously variable transmission configured as described above will be described. The input sheave shaft 5 rotates via the clutch 2 and the synchro coupling 6 by the driving of the prime mover E. Then, in the input sheave 22, the sheave position adjusting device 17 controls the position of the input movable sheave 16 in accordance with the driving situation, and the groove width of the V-shaped groove 21 is adjusted. To fluctuate. On the other hand, in the output sheave 24, the output movable sheave 20 is axially displaced in accordance with the fluctuation of the winding diameter of the V-belt 25 described above. However, the movable sheave 20 is pushed by the spring 40 toward the fixed sheave 19,
The V-belt 25 constantly transmits the driving force to the output sheave 24 in a tensioned state through the pressure contact between each roller 42 and the cam surface 38, whereby the rotation of the output sheave shaft 18 is continuously variable. During this time, each roller 42 rotates by the rotation of the roller hub 39, and the roller 42 moves smoothly along the cam surface 38, so that the cam thrust is secured.

The torque cam 37 has an output movable sheave 2
The vibration of the belt 25 is transmitted from 0 to the torque cam 37.
This vibration produces a knocking motion force between the roller 42 and the cam surface 38 which are in contact with the cam surface 38 of the roller. Accordingly, the cam surface 38 was extremely worn.
However, in this example, the elastic plate 45 is interposed on the upper surface of the roller 42, and the roller 43 is
When the tapping movement force is generated, the outer periphery of the roller 42 is formed in a tapered surface, so that the roller 42 receives a force in the outward direction.
The striking force generated by the vibration is absorbed by the elastic plate 45 interposed therebetween, and the striking force generated by the vibration is well absorbed by the elastic plate 45. Therefore, the roller 42 does not strike the cam surface 38 due to the striking motion, and the wear of the cam surface 38 is reduced, resulting in a torque cam having high durability.

[0014]

The torque cam of the continuously variable transmission according to the present invention includes a pair of detachable input pulley sheaves attached to the input sheave shaft and a pair of detachable output pulley sheaves attached to the output sheave shaft. The output pulley sheave approaches the fixed pulley sheave at the output pulley sheave in order to transmit the output sheave shaft by changing the rotation of the input sheave shaft in a stepless manner by the belt wound between the output pulley sheave and the belt. The outer surface of the movable pulley sheave urged in the direction to be moved, and one of the opposing surfaces of the fixing member fixed to the output sheave shaft so as to oppose the outer pulley sheave is concentric with the output sheave shaft and A cam surface is formed over the entire circumference,
On the other side, a torque cam mechanism having a roller that rolls on the cam surface is provided, and the roller has an outward direction.
The outer peripheral surface is formed in a tapered shape so as to receive the force
At the same time, because the bolts are stopped via the elastic plate, even if the kinetic force acts between the cam surface and the roller due to the vibration applied to the torque cam, this kinetic force is well absorbed by the elastic plate and The roller is not hit, the wear on the cam surface can be reduced, and a highly durable torque cam can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall schematic configuration diagram of a continuously variable transmission.

FIG. 2 is an enlarged sectional configuration view of a main part around a movable sheave on an output side.

FIG. 3 is an overall perspective view of an assembled state of a torque cam.

FIG. 4 is an exploded perspective view of components of the torque cam.

[Explanation of symbols]

 5 Input sheave shaft 18 Output sheave shaft 22 Input sheave 24 Output sheave 25 V belt 37 Torque cam 38 Cam surface 39 Roller hub 40 Spring 41 Boss 42 Roller 43 Bolt 45 Elastic plate

Claims (1)

(57) [Scope of request for utility model registration] 1. An input sheave comprising a pair of detachable input pulley sheaves attached to an input sheave shaft and a belt wound between a pair of detachable output pulley sheaves attached to an output sheave shaft. A movable pulley sheave urged in a direction approaching a fixed pulley sheave at the output pulley sheave in order to transmit the rotation of the shaft to the output sheave shaft by continuously changing the rotation of the shaft and to apply tension to the belt. The cam surface is formed over the entire circumference on the outer surface of the shaft and on one of the opposing surfaces of the fixing member fixed to the output sheave shaft so as to face the outer surface, On the other side, there is a torque cam mechanism equipped with a roller that rolls on this cam surface, and the roller has a tapered outer peripheral surface so as to receive a force outward.
A torque cam for a continuously variable transmission, wherein the torque cam is formed with a bolt through an elastic plate.