JPH0244121Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) This invention relates to a drive V-pulley of a V-belt automatic transmission whose speed is controlled by centrifugal rollers.

(Technical background of the invention and its problems) The drive V-pulley of the V-belt automatic transmission that uses centrifugal force control has a fixed face and a movable face arranged opposite each other, and a centrifugal roller set on the back of the movable face to move between the two faces. The interval is now being increased or decreased. The speed change is determined by the distance between both faces, and the distance is controlled by the diameter and mass of the centrifugal roller, the shape of the inclined surface that generates the axial component of the centrifugal force, etc., and a predetermined speed change characteristic is set. The transmission characteristics must be matched to the engine output characteristics.
This is important in determining the performance of motorcycles and the like that use this type of transmission.

However, due to dimensional tolerances of the centrifugal rollers and other functional parts, variations occur in the speed change characteristics of individual products. To prevent this, it is necessary to improve the precision of each component, but this has a problem in that it has an extremely large impact on cost.

(Purpose of the invention) In view of the above-mentioned problems, the purpose of this invention is to prevent variations in transmission characteristics by introducing a part whose relative dimensions can be adjusted after assembly.
The present invention provides a drive V-pulley for a belt automatic transmission.

(Summary of the invention) In line with the above-mentioned purpose, this invention focuses on the fact that variations in transmission characteristics are mainly caused by dimensional tolerances in the axial direction, and is configured as follows. That is, in a drive V pulley of a V-belt automatic transmission, a fixed face and a movable face are disposed oppositely on the drive shaft, and a centrifugal roller is held between the back of the movable face and a ramp plate fixed to the drive shaft. The lamp plate is screwed onto a screw provided on the drive shaft to be pivotally supported, and can be fixed in an axially adjustable manner by a nut screwed onto the screw adjacent to the lamp plate. be.

(Embodiment of the invention) The drawings showing the embodiment of this invention will be explained below.

Reference numeral 1 indicates an engine crankshaft, and a rotatable tube shaft 2 is provided. Centrifugal shoe 3 provided at the first end of the crankshaft and clutch housing 4 provided at the second end of the tube shaft
A development clutch 5 is formed by the above, and the crankshaft 1 and the tube shaft 2 become integrated at a predetermined rotation speed or higher.

A fixed face 7 of a drive V pulley 6 is fixed to the tube shaft 2. Further, a spacer 11 is provided on the tube shaft 2 and is rotatably and integrally aligned by a spline 9 and integrally connected in the axial direction by a nut 10. A movable face 8 that can freely slide in the axial direction is pivotally supported. The fixed face 7 and the movable face 8 rotate integrally and face each other so that the interval can be changed, forming a drive V pulley 6, and a V belt 13.
is suspended and transmits rotation to the driven V pulley.

Next, on the back side of the movable face 8, there is a groove 1 in the centrifugal direction.
4 is formed and a centrifugal roller 15 is housed therein. Groove 1
The bottom surface 16 is inclined in a direction away from the fixed face 7 in the centrifugal direction. Also, the centrifugal roller 15
A ramp plate 17 is placed at the back of the lamp plate 17, which is inclined toward the fixed face 7 in the centrifugal direction. This lamp plate 17 is connected to the spacer 11.
It is screwed into the upper screw 18 and is pivotally supported, and the screw 18
A nut 19 is screwed adjacent to the lamp plate 19 to fix the lamp plate 17 in a double nut manner. That is, the lamp plate 17 can be fixed on the spacer 11 so that its axial position can be adjusted.

With the above configuration, the starting clutch 5 acts as the engine speed increases, and the drive V pulley 6
starts rotating. At this time, the movable face 8 is retracted by the tension of the V-belt 13, and the interval is widened, and the effective diameter of the drive V-pulley 6 is small and it is in a low speed range. As the rotational speed increases, the centrifugal force of the centrifugal roller 15 increases, and the movable face 8 moves forward due to the axial component force due to the groove bottom surface 16 and the inclined surface of the ramp plate 17, reducing the distance between the movable face 8 and the fixed face 7. As a result, the effective diameter of the V-belt increases and the gear ratio shifts to a high speed range.

This speed change characteristic is mainly determined by the inclination angle of both the groove bottom surface 16 and the ramp plate 17, which the front and rear edges of the centrifugal roller 15 contact, but by adjusting the ramp plate 17 in the axial direction, the axis of the centrifugal roller 15 The distance from the center changes, that is, the centrifugal force changes, and the speed change characteristics change. Most of the variations in speed change characteristics due to dimensional tolerances of each functional component can be corrected by this adjustment.

(Effects of the invention) As described above, the drive V pulley of the V-belt automatic transmission according to this invention has a simple structure in which the ramp plate can be displaced in the axial direction by a screw, and the speed change characteristics can be improved. This makes it possible to correct variations, and it is effective in providing products with stable driving performance and fuel efficiency without the need for strict precision control, and therefore without significantly increasing costs.

[Brief explanation of the drawing]

The figure is a longitudinal cross-sectional view of a drive V pulley of a V-belt automatic transmission showing an embodiment of this invention. 1...Crankshaft, 6...Drive V pulley,
7... Fixed face, 8... Movable face, 15
... Centrifugal roller, 17 ... Lamp plate, 18
...Neji, 19...Natsuto.

Claims (1)

[Scope of utility model registration request] In the drive V pulley of a V-belt automatic transmission, a fixed face and a movable face are arranged oppositely on the drive shaft, and a centrifugal roller is held between the back of the movable face and a ramp plate fixed to the drive shaft. A V-belt automatic transmission characterized in that a plate is screwed onto a screw provided on a drive shaft to be pivotally supported, and can be fixed in an adjustable axial position by a nut screwed onto an adjacent screw. Machine drive V pulley.