JPH0245288A - Reaction unit - Google Patents

Abstract

PURPOSE:To simplify the design and structure of a pair of rear cushions for a motorcycle by providing a body height adjustment mechanism at one of the cushions. CONSTITUTION:There are provided at one of rear cushions 5 a motorcycle height adjustment mechanism comprising an inner cylinder 11, outer cylinder 12, piston rod 14, rod 13, position detecting oil hole 15, oil chamber S2, valves 31, 32 and the like. There are provided, on the other hand, at the other a damping force generation mechanism comprising a cylinder 61, hollow rod 62, piston 64, compression side valve 67, extension side valve 68, and the like. With this arrangement, it is possible to adjust the height automatically and to damp oscillations so as to function the damping performance, resulting in the simplification of design and structure.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rear cushion unit for a motorcycle comprising left and right rear cushions.

(Prior art) Conventional motorcycle rear cushion units have been designed as a pair of left and right rear cushions, for example, in order to have a function to automatically adjust the vehicle height when the depression of the cushion changes due to loading etc. 1986. -20190
Hydraulic &! Self-help vehicle height adjustment mechanism equipped with a vehicle height adjustment mechanism and a damping force generation mechanism as described in Publication No. 1! Town equipment (
dampers) are known.

(Problems to be Solved by the Invention) If a damper with an automobile height adjustment mechanism is provided as a pair of left and right rear cushions like the above-mentioned rear cushion unit, the design and configuration of not only the damper but also the rear cushion unit itself is complicated. , and it becomes expensive in terms of cost.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a vehicle height adjustment mechanism for one of the pair of left and right rear cushions, and generates a damping force for the other rear cushion. A mechanism was established.

(Function) One cushion has a vehicle height adjustment mechanism, so if the cushion changes due to loading etc., the vehicle height can be automatically adjusted, and the other cushion has a cushioning function. Because it has the same structure, it is possible to reduce vibrations, etc., and there is no need to provide a vehicle height adjustment mechanism and a shock absorbing function in one cushion.The design of the rear cushion unit is simplified, and the configuration of each rear cushion is also adjustable. It gets easier.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a rear view of a motorcycle equipped with rear cushion units 1 to 1 according to the present invention, FIG. 2 is a sectional view of one rear cushion of the same unit, and FIG. 3 is a sectional view of the other rear cushion of the same unit. 4, and 5 are enlarged sectional views of main parts of FIG. 2 showing different states of one of the rear cushions.

A rear cushion unit 4 is interposed between the main body 1 and the wheels 3 of the rear wheel 2 of the motorcycle, and this rear cushion unit 4 has a pair of left and right vehicle height adjustment mechanisms, an accelerator 5 and a buffer function. It consists of a rear cushion 6.

One rear cushion 5 has an inner cylinder 12 disposed within an outer cylinder 11, as shown in FIG.
A rod 13 is inserted into the inner cylinder 12 from above, and a piston 14 is attached to the lower end of the rod 13 to slide on the inner circumferential surface of the inner cylinder 12. A position detection oil hole 15 for detecting the position of the piston 14 is formed in the oil hole 15, and this oil hole 15 connects the oil chamber (hereinafter referred to as "inner cylinder oil chamber") Sl in the inner cylinder 12 and the cylinder inner sleeve chamber. S1 communicates with an oil chamber (hereinafter referred to as "oil reservoir chamber") 32 between the outer cylinder 11 and the inner cylinder 12.

The upper end of the inner cylinder 12 is attached to the lower end of the rod guide 17 that guides the rod 13 on the inner peripheral surface of the upper end of the outer cylinder 11, and An oil seal 18 is fitted to the upper end of the rod 13 to attach it to the vehicle body 1, and an upper bracket 20 for attaching the rod 13 to the vehicle body 1 is attached to the lower surface of the upper bracket 20.
A stop rubber 21 is attached to the outer periphery of the upper spring seat 2 at the lower end of the upper bracket 20.
2 is locked.

A lower bracket 25 for attaching to the wheel 2 is attached to the lower end of the outer cylinder 11, and a cylindrical body 26 is placed in the bottom surface of the lower bracket 25 to form a jacking chamber S3. There is an oil hole 28 that communicates inside and outside.
A check valve unit 30 consisting of a first valve unit 31 and a second valve unit 32 is disposed above the cylindrical body 26.

The first valve unit 31 has a first bottom piece 33 fitted to the inner circumferential surface of the lower end of the outer cylinder 11.
A return control orifice 34 is formed in the center of the bottom piece 33 to control the amount of hydraulic oil returned from the jack chamber S3 to the oil chamber S1 in the inner cylinder 12. An oil hole 35 that communicates with the cylinder oil chamber S1 and the jack chamber S3 is formed around the oil hole 35, and a spring interposed between the first bottom and a plate 36 attached to the lower surface of the spacer 33 is formed in the oil hole 35. A check ball 38 is interposed therebetween, which is urged upward by a force 37.

A second bottom piece 40 is fitted into the second valve unit 32 between the inner peripheral surface of the lower end of the outer cylinder 11 and the first bottom piece 33 of the first valve unit 31. An oil hole 41 that communicates with the oil hole 35 of the first bottom piece 33 of the first valve unit 31 and between the cylinder oil chamber S1 and the jack chamber S3 is formed, and an oil hole 41 is formed on the lower surface of the second bottom piece 40. Furthermore, an oil hole 43 is formed in the second bottom piece 40 that communicates with the cylinder oil chamber S1 and the oil reservoir chamber S2 via these oil holes 41 and oil grooves 42. Oil hole 43
Inside is a check ball 4 which is biased upward by a spring 44 interposed between the top surface of the first bottom piece 33 and the top surface of the first bottom piece 33.
5 is interposed.

Further, the lower end of the inner cylinder 12 is fitted into the upper end of the second bottom piece 40 of the second valve unit 32, and a free piston 46 is fitted inside the inner cylinder 12.
A rubber sheet 47 is fitted to the lower end of the free piston 46 for when the free piston 46 comes into contact with the opening of the control orifice 34 of the first bottom piece 33. It is supported by a position detection spring 48 interposed therebetween and a position detection spring 49 interposed between the second bottom piece 40 and the second bottom piece 40 .

A jack cylinder 51 is fitted to the outer circumferential surface of the lower end of the outer cylinder 11, and a jack piston 52 is slidably fitted between the inner circumferential surface of the jack cylinder 51 and the outer circumferential surface of the outer cylinder 11. , this jack piston 52
A lower tube spring 53 is interposed between the upper end portion and the upper spring seat 22 that is locked by the upper bracket 20,
In addition, a jack chamber S3 is provided at the lower end of the outer cylinder 11.
An oil hole 54 is formed to communicate between the jack inner chamber S4 located below the jack piston 52, and a blow orifice 55 is formed at a position corresponding to the upper part of the jack cylinder 51 of the outer cylinder 11. In addition, a high-pressure O-ring 56 is provided on the lower side of the inner peripheral surface of the jack piston 52.
A low pressure O-linog 57 is fitted on the upper side.

The other rear cushion 6 has a hollow rod 62 inserted into the cylinder 61 from below, and a piston 64 that slides on the inner peripheral surface of the cylinder 61 is attached to the tip of the hollow rod 62, so that the inside of the cylinder 61 is filled with upper oil. It is defined into a chamber S5 and a lower oil chamber S6, and the piston 64 is formed with a compression side oil passage and an extension side oil passage 66 (not shown), and a compression side oil passage (not shown) is formed on the lower surface of the piston 64 to open and close the compression side oil passage. A side valve 67 is fitted, and an elongation side pulp 68 for opening and closing the elongation side oil passage 66 is attached to the upper surface.

Further, a cylinder cap 70 is fitted to the inner peripheral surface of the lower end of the cylinder 61, a rod guide 71 is fitted to the upper side of the cylinder cap 70, and the outer peripheral surface of the hollow rod 62 is fitted to the inner peripheral surface of the rod guide 71. Bush 72 that slides into contact with
An oil seal 73 is fitted to the lower surface of the rod guide 71 to make sliding contact with the outer surface of the hollow rod 62, and a partition 75 is fitted to the inner peripheral surface of the upper end of the cylinder 62. Attach the bladder 76 and use this bladder 76.
The upper part is a gas chamber sA, and an upper bracket 77 for attachment to the vehicle body 1 is attached to the upper end of the cylinder 61.

Further, a lower bracket 80 for attaching to the wheel 2 is attached to the lower end of the hollow rod 62, a retainer 81 is attached to the upper surface of this lower bracket 80, and a stop rubber 82 is fitted onto this retainer 81. ing.

A bypass oil passage 84 that bypasses the piston 64 is formed at the upper end of the hollow rod 62, and this hollow rod F
An adjuster mechanism 87 is provided in the lower bracket 80 to move the bushing rod 86 forward and backward into the lower bracket 80 by inserting a bushing rod 86 having a needle 85 at its tip for changing the frontage area of the bypass oil passage 84 so that the bushing rod 86 can move forward and backward. .

This adjuster mechanism 87 has an adjuster rod 88 fitted into the lower bracket 80 so as to be able to move forward and backward in a direction perpendicular to the axial direction. A stopper 90 is fitted in front of the adjuster rod 88 of the lower bracket 80.

The operation of the rear cushion unit configured as above will be explained below.

First, to discuss the function of the rear cushion 5, if the cushion 5 does not sink in due to low loading weight, the piston 5 in the inner cylinder 12
4 strokes above the position detection oil hole 15 of the inner cylinder 12, so when the piston 14 moves downward, the hydraulic oil in the cylinder inner chamber S1 flows out through the oil hole 15 into the oil reservoir chamber s2. Further, when the piston 14 moves upward, the hydraulic oil in the oil reservoir chamber S2 flows into the cylinder oil chamber S1 through the oil hole 15, and in either case, the first check valve 31 does not open, so the The hydraulic oil will not flow into S4 and the jack piston 52 will not rise.

On the other hand, if the cushion 5 sinks further due to an increase in the loaded weight, the piston 14 in the inner cylinder 12 strokes below the position detection oil hole 15 of the inner cylinder 12, so the piston 14 When the valve moves downward, the pressure in the cylinder oil chamber S1 rises, and the hydraulic oil in the cylinder oil chamber S1 flows from the oil hole 41 of the second valve unit 31 to the oil hole 35 of the first valve unit 31 to spring the check ball 38. 37 to open the cylinder, the hydraulic oil in the cylinder oil chamber S1 flows into the jack chamber S3 through the oil hole 41.35, and then flows into the jack chamber S4 through the oil hole 28.54. As a result, the jack piston 52 is pushed up and the set load of the suspension spring 53 becomes higher, raising the vehicle height. At this time, the hydraulic fluid is throttled and returned from the jack chamber S3 to the cylinder oil chamber S1 via the control orifice 34, thereby preventing the vehicle height from rising suddenly.

Then, when the set load of the suspension spring 53 increases and the vehicle height rises, the rod 13 rises together with the piston.
The hydraulic oil in the jack chamber S3 returns to the cylinder oil chamber S1 through the return control orifice 34, and the hydraulic oil in the jack chamber S4 returns to the jack chamber S3 through the oil hole 54.
Then, the jack piston 52 descends as it further passes from the jack chamber S3 to the in-cylinder oil chamber S1. At this time,
By restricting the return of hydraulic oil from the jack chamber S3 to the cylinder oil chamber S1 by the orifice 34, a sudden drop in vehicle height is prevented.

By repeating these operations, the vehicle height is maintained constant regardless of the loaded weight.

In this case, when the piston 14 moves upward below the position detection oil hole 15, the check ball 45 of the second valve unit 32 moves downward against the biasing force of the spring 44 and becomes open. The hydraulic oil in the reservoir chamber S2 flows through the oil hole 43,
It flows into the cylinder oil chamber S1 through the oil groove 42 and the oil hole 41, and does not inhibit the upward movement of the piston 14.

In addition, when the piston 14 is depressed to a certain level or more and strokes due to the increased load, the position detection spring 48 is compressed by the piston 14, as shown in FIG. 48, the free piston 46 descends and compresses the position detection spring 49, and the rubber seat 4 of the free piston 46
7 closes the upper opening of the return control orifice 34, and the hydraulic oil in the jack chamber S3 no longer returns to the cylinder oil chamber S1 through the return control orifice 34. Therefore, since the hydraulic oil continues to flow into the jack chamber S3 due to the downward movement of the piston 14, the jack piston 52 rises rapidly, and the vehicle height can be returned to a constant state in a short time.

Furthermore, when the O-ring 56 on the inner peripheral surface of the jack piston 52 rises above the blow orifice 55 of the outer cylinder 11, the hydraulic oil in the jack interior chamber S4 returns to the oil reservoir chamber S2 via the blow orifice 55, This prevents the jack piston 52 from rising excessively.

Next, to describe the action of the other rear cushion 6, as the piston 64 moves upward during the compression stroke, the hydraulic oil in the upper oil chamber S5 opens the compression side valve 67 through the compression side oil passage (not shown) of the piston 64. Lower oil chamber S6
When the piston 64 moves downward during the extension stroke, the hydraulic oil in the lower oil chamber S6 passes through the extension oil passage 66 of the piston 64 and opens the extension pulp 68, causing the oil to flow into the upper part. It flows into the oil chamber S5 and generates a damping force.

In this case, when the hollow rod 62 enters into the cylinder 61, the bladder 76 expands upward while compressing the gas chamber SA by a volume corresponding to the entering volume of the hollow rod 62, and the hollow rod 62 enters the cylinder 61 from inside the cylinder 61. When the hollow rod 62 withdraws, the bladder 76 contracts downward by the internal pressure of the gas chamber SA by a volume corresponding to the volume of the hollow rod 62 withdrawn.

As mentioned above, one rear cushion 5 of the rear cushion unit 4 has a vehicle height adjustment function, so when the vehicle height changes due to the loaded weight etc., it automatically adjusts the vehicle height to be constant. The other rear cushion 6 has a 111 function, so it generates a damping force against vibrations.
l Advantageously, the damping force generation mechanism is installed in the rear cushion 5.
Vehicle height adjustment and damping force generation can be performed without providing a vehicle height adjustment mechanism on the rear cushion 6.

(Effects of the Invention) As explained above, according to the present invention, one of the pair of left and right rear cushions has a vehicle height adjustment function, and the other rear cushion has only a damping force generation function. This makes it possible to automatically adjust the vehicle height when the cushion changes due to loading, etc., and also to buffer vibrations, etc., combining vehicle height adjustment function and damping force in one cushion. Since there is no need to provide a generating function, the rear cushion unit can be easily designed, the configuration of each rear cushion can be simplified, and the cost can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a rear view of a motorcycle equipped with a rear cushion unit according to the present invention, FIG. 2 is a sectional view of one rear cushion of the same unit, and FIG. 3 is a sectional view of the other rear cushion of the same unit. , 4 and 5 are enlarged cross-sectional views of essential parts of FIG. 2 showing different states of one of the rear cushions. In the drawings, 1 is the motorcycle body, 2 is the wheel, 4 is the rear cushion unit, 5.6 is the rear cushion, 11 is the outer cylinder, 12 is the inner cylinder, 13 is the rod, 14 is the piston, and 15 is the oil hole. , 26 is a cylinder, 30
is the check valve unit, 46 is the free piston, 5
1 is a jack cylinder, 52 is a jack piston, 53
is a suspension spring, 61 is a cylinder, 62 is a hollow rod, 64
is the piston, SL is the oil chamber in the cylinder, S2 is the oil reservoir chamber, S
3 is a jack chamber, SA is a jack chamber, S5 is an upper oil chamber, S6 is a lower oil chamber, and SA is a gas chamber. Figure 4

Claims (1)

[Claims] A rear cushion unit for a motorcycle consisting of a pair of left and right rear cushions, characterized in that one rear cushion is provided with a vehicle height adjustment mechanism, and the other rear cushion is provided with a damping force generation mechanism.