JPH0247788Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an improvement of a vehicle height adjustable hydraulic shock absorber.

(Prior art) As a hydraulic shock absorber used in motorcycles, etc., a spring receiver that supports one end of a suspension spring stretched between a cylinder and a piston rod is slidably fitted onto the outer periphery of the cylinder. A hydraulic shock absorber is known in which the vehicle height is adjusted by sliding the suspension spring against the cylinder and changing the set length of the suspension spring. However, in these hydraulic shock absorbers, the sliding of the spring receiver was performed manually, making the adjustment work troublesome and requiring a great deal of effort.

Therefore, the applicant of the present invention previously proposed a hydraulic shock absorber in which pressure was generated by a motor and a spring holder was slid by this pressure in Utility Application No. 58-118225. (Problems to be solved by the invention) The above-mentioned hydraulic shock absorber has a spring holder for a suspension spring slidably provided on the outer periphery of the cylinder, a pressure chamber is formed between this spring holder and the cylinder, and this pressure chamber When increasing the vehicle height by connecting a communication circuit such as a hose to the hydraulic pressure generation chamber of a separate hydraulic pressure generation device, the motor is rotated in the forward direction to increase the pressure in the hydraulic pressure generation chamber and the hydraulic oil is transferred to the pressure chamber. When lowering the vehicle height, the motor is rotated in the opposite direction to increase the volume of the oil pressure generation chamber, and the hydraulic oil in the pressure chamber is moved by that amount into the oil pressure generation chamber. This is what I tried to change back to.

In this way, in the case of conventional vehicle height adjustable hydraulic shock absorbers, the pressure generation chamber and the pressure chamber are connected with a single hose, etc., so even if the vehicle height is raised, it can be lowered again. In this case, the motor must always be rotated by a predetermined amount, which takes time. In particular, for off-road type motorcycles, it is desirable to be able to raise the vehicle height when driving and instantaneously lower the vehicle height when stopped to improve footing. However, with conventional structures, There is a disadvantage that it takes time to change the vehicle height from a high state to a low state.

(Means for Solving the Problems) In order to solve the above problems, the present invention has a spring support that supports one end of a suspension spring stretched between the cylinder and the piston rod, and is slidably fitted to the outer periphery of the cylinder. In addition, in the vehicle height adjustable hydraulic shock absorber in which a pressure chamber communicating with a pressure generation chamber of a separately provided pressure generation device is formed between the spring receiver and the cylinder, the pressure generation device includes a pressure generation chamber and a pressure chamber. A communicating sub-tank is provided, the sub-tank and the pressure chamber are communicated through a bypass circuit, and an on-off valve is provided in the middle of the bypass circuit to communicate the circuit when lowering the vehicle height. .

(Function) When the on-off valve is opened when the vehicle height is high, the hydraulic oil or gas in the pressure chamber is collected into the sub-tank through the bypass circuit, and the vehicle height is instantaneously lowered.

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

FIG. 1 is a partial sectional view of a hydraulic shock absorber according to the present invention, and FIG. 2 is a partially enlarged view of FIG. A piston 4 is fitted to the upper end of the piston rod 3 so as to be vertically slidable on the inner surface of the cylinder 2.
A damping force generating mechanism 5 is provided.

A reinforcing member 6 is fixed to the outer periphery of the cylinder 2, and an upper spring receiver 7 is slidably and airtightly fitted onto the outer periphery of the reinforcing member 6. Further, the lower end of the piston rod 3 is installed in a lower metal 8, a stop lever 9 is fixed to the upper surface of the lower metal 8, and a lower spring receiver 10 which also serves as a cover is fixed to the periphery.
A suspension spring 11 is stretched between these spring supports 7 and 10.

On the other hand, an annular member 12 is interposed between the upper spring receiver 7 and the reinforcing member 6, and this annular member 12,
The pressure chamber S1 is formed by the reinforcing member 6 and the upper spring support 7.
is formed.

Furthermore, the inside of the main body casing of the pressure generator 13, which is arranged separately from the hydraulic shock absorber 1, is divided into two spaces by a partition wall 14, one space houses a motor 15, and the other space houses a motor 15. A threaded rod 16 and a slider 17 screwed onto the threaded rod 16 are housed, and the slider 17 forms a pressure generating chamber S2 in the other space. and motor 1
5 is connected to a battery 20 via a forward/reverse switch 18 and a breaker 19, and the output shaft of the motor 15 is equipped with a speed reduction mechanism 21 consisting of a three-stage planetary gear train.
are connected, and this deceleration mechanism 21 and the threaded rod 16
are connected by a gear 22. The rotation of the motor 15 causes the slider 17 to move forward and backward, and the pressure within the pressure generating chamber S2 changes in accordance with this forward and backward movement.

Further, the pressure generating chamber S2 and the pressure chamber S1 communicate with each other via a hose 23 and a through hole 24 formed in the upper spring receiver 7. Furthermore, a sub-tank 25 is attached to the pressure generator 13, and this sub-tank 2
5 communicates with the pressure generating chamber S2 through a through hole 26, and communicates with the pressure chamber S1 through a hose 27 and a through hole 28 formed in the upper spring receiver 7. to configure a bypass circuit. A solenoid valve 29, which is an on-off valve, is provided in the middle of the through hole 28 forming a part of the bypass circuit, and this solenoid valve 29 is connected to the battery 20 via a switch 30.

The operation of the hydraulic shock absorber 1 having the above structure will be described below.

First, if you want to raise the vehicle height, turn forward/reverse switch 1.
8 to rotate the motor 15 in the forward direction. Then, the rotation of the motor 15 is transmitted to the threaded rod 16 via the reduction mechanism 21, and the slider 17 moves to the left due to the rotation of the threaded rod 16, increasing the pressure in the pressure generation chamber S2 and causing the operation in the pressure generation chamber S2. Fluid (oil or gas) flows into the pressure chamber S1, the pressure within the pressure chamber S1 increases, and the cylinder 2 is relatively moved upward, increasing the vehicle height. In this case, the switch 30 is turned off, and the solenoid valve 29 closes the through hole 28.

On the other hand, when lowering the vehicle height, switch 30
Turn on. Then, the bypass circuit connects,
The working fluid in the pressure chamber S1 is returned directly into the sub-tank 25 via the through hole 28 and the hose 27 by the elastic force of the suspension spring 11, and a part of the working fluid returned to the sub-tank 25 is returned to the pressure generating chamber S2. flows into the rear of the In this way, since the working fluid in the pressure chamber S1 directly returns to the sub-tank 25, the vehicle height can be switched from a high state to a low state instantly.

At the same time as or after the operation to lower the vehicle height, the forward/reverse switch 18 is operated to control the motor 15.
, and return the slider 17 to its original position.
Prepare for the next time you want to raise the vehicle height.

(Effects of the invention) As explained above, according to the invention, in a vehicle height adjustable hydraulic shock absorber equipped with a pressure generating device,
A sub-tank is attached to the pressure generator, and when the vehicle height is lowered, the working fluid in the pressure chamber formed in the spring receiver flows directly into the sub-tank via a bypass circuit, so that the vehicle height can be lowered even when the vehicle height is high. It is possible to instantly switch to a low state, and when applied to off-road motorcycles, for example, it can improve footing when stopped, and the load is small when reversing the motor. It has many effects such as extending the life of the motor.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional view of a hydraulic shock absorber according to the present invention, and FIG. 2 is a partially enlarged view of FIG. 1. In addition, in the drawing, 1 is a hydraulic shock absorber, 2 is a cylinder, and 3 is a hydraulic shock absorber.
is a piston rod, 7 is a spring receiver, 11 is a suspension spring, 13 is a pressure generator, 15 is a motor, 16 is a threaded rod, 17 is a slider, 18 and 30 are switches, 21 is a reduction mechanism, 25 is a sub-tank, 27,
28 is a bypass circuit, 29 is a solenoid valve,
S1 is a pressure chamber, and S2 is a pressure generation chamber.

Claims (1)

[Scope of utility model registration request] A spring holder that supports one end of a suspension spring stretched between the cylinder and the piston rod is slidably fitted to the outer periphery of the cylinder, and a pressure chamber that communicates with a pressure generation chamber of a separately provided pressure generation device is connected to the spring holder. In the height-adjustable hydraulic shock absorber formed between a cylinder and a cylinder, the pressure generating device is provided with a sub-tank that communicates with the pressure generating chamber, and the sub-tank and the pressure chamber are communicated through a bypass circuit. A vehicle height adjustable hydraulic shock absorber, characterized in that an on-off valve is provided in the middle of the bypass circuit to communicate the circuit when lowering the vehicle height.