JPS59179413A - Shock absorber - Google Patents

Abstract

PURPOSE:To reduce vibration of a vehicular body system, by operating a cylinder arranged parallel to a spring between an axle and a vehicular body as a hydraulic actuator according to magnitude and direction of acceleration of the vehicular body system in a shock absorber for a vehicle. CONSTITUTION:When upward large acceleration is applied to a vehicular body system 2, a damping operation of a spring 4 and a cylinder 3 is acted against a force from an axle system 1, and a signal 6a from an acceleration sensor 2a is inputted in a calculator 6. The calculator 6 serves to select a selector valve 5 to a select position 5A on the basis of the signal, and simultaneously close an on-off valve 3e. Accordingly, a hydraulic pressure 5a is forcibly fed to an upper cylinder chamber 3b to facilitate emission of oil in a lower cylinder chamber 3c. Accordingly, a downward force is acted on a piston 3a, and an upward pushing force from the axle system 1 is buffered to reduce transmission of vibration to the vehicular body system 2. Thus, vehicular vibration may be reduced even at high speed running.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shock absorber used in vehicles such as automobiles.

Conventionally, shock absorbers in vehicles are composed of a spring system and a damping system that absorbs vibrations, so they absorb the vibrations, but they also actively dampen the vibrations of the vehicle itself depending on the magnitude of the vibrations. The structure is not designed to minimize control, so when a vehicle is loaded with fragile items, the speed of the vehicle must be slowed down as much as possible to reduce vibrations applied to the entire vehicle.

As a result, in such a case, there is a problem in that the mobility of the vehicle cannot be effectively utilized.

An object of the present invention is to provide a shock absorber for a vehicle that has improved the above-mentioned problems.

Hereinafter, the present invention will be explained based on Examples.

FIG. 1 shows a shock as an embodiment of the present invention.
The absorber is shown in a system diagram.

The axle 1, which is the unsprung weight of the vehicle, and the vehicle body 2, which is the unsprung weight of the vehicle, are combined with a spring 4 and a cylinder body 3, and a detector 2a is fixedly installed in the vehicle body 2. ing.

In the cylinder 3f of the cylinder body 3, the cylinder 3
The piston 3a is fitted to allow sliding movement in the axial direction at f, and the displacement chambers 3b and 3C are in communication via the on-off valve 3e and the throttle channel 3d.

Displacement chambers 3b and 3C formed above and below the piston 3a are respectively connected to the switching valve 5, and between the reservoir 5b and the switching valve 5, a hydraulic pump 5a is connected to the hydraulic pressure supply side of the switching valve 5. is provided, and its discharge side directly communicates with the reservoir 5b.

The detection signal from the detector 2a is input to the calculator 6 via the wiring 6a, and the output from the calculator 6 is input to the wiring 6.
b and 6C, the on-off valve 3e and the switching valve 5
is man-powered.

The operation of the above configuration will be explained below.

When the vehicle runs, vibrations are transmitted from heavy wheels (not shown) to the axle system 1, and the vibrations are transmitted to the vehicle system 2 via the spring 4 on one side and the cylinder body 3 on the other side.

For this reason, when the vehicle runs, vertical vibrations occur in the vehicle system 2, and the vertical acceleration caused by the vibrations is detected by the detector 2a, and the direction of the detected acceleration is The size is transmitted to the calculator 6 via the wiring 6a.

The calculator 6 compares the absolute value of the signal 6 via the wiring 6a with a predetermined value, and when the signal value is smaller than the predetermined value, the counter 6 switches the switching valve 5. Set to position 5B, and set on/off jr3e to open state.

This means that each of the displacement chambers 3b and 3C has 1
, the communication with the hydraulic pump 5a or the reservoir 5b is closed, and the throttle channel 3d is connected to the displacement chamber 3b and the displacement chamber 3.
This results in communication with C.

As a result, in a state where the vertical vibration in the heavy system 2 is smaller than a predetermined value, the shock absorber shown in FIG. 1 has the same structure as a normal shock absorber.

On the other hand, Kai! ! When the absolute value of the signal 6a becomes larger than a predetermined value, the switching valve 5 and the on/off valve 3e are operated to cause the cylinder body 3 to function not as a mere damper but as a hydraulic actuator. will also be activated.

Such a state where the signal value in the wiring 6a becomes large means that the vibration in the vehicle system 2 becomes large.
The operation in this state will be explained below.

(a) When a large upward acceleration is applied to the vehicle system 2.

In this case, the axle system 1 attempts to push the vehicle system 2 upward, thereby causing the vehicle system 2 to undergo a large acceleration upward.

Further, in this case, at the initial stage when the acceleration starts to occur, the switching position of the switching valve 5 is still 5B.
The on/off valve 3e is set to the open position.

To break down and explain this operation at the initial stage when such acceleration begins to occur, the force from the axle system 1 is -
The force is transmitted to the vehicle system 2 via the spring 4, and on the other hand, the force pushes the cylinder 3f upwards and tries to eliminate the hydraulic fluid in the displacement chamber 3C.

As a result, the hydraulic oil in the displacement chamber 3C flows through the flow path 3.
d, and is about to be pushed away to the displacement chamber 3b, but at this time, since the throttle channel 3d exists, resistance is created to the flow of hydraulic oil flowing through the throttle channel 3d, and the hydraulic oil is not applied to the displacement chamber 3c. As a result, the piston 3a is also in a state where it is pushed out.

However, when the vehicle body 2 is about to be pushed upwards, the calculator 6 detects the state in which the vehicle body 2 is about to be pushed upwards by a signal from the wiring 6a, and by that sensing, the calculator 6
is set to the switching position 5A, and the on/off valve 3e is closed.

As a result, the pressure oil from the hydraulic pump 5a is actively pumped to the displacement chamber '3b, and the hydraulic oil from the displacement chamber 3-C is discharged to the reservoir 7 through the switching valve 5b. .

In this way, when the on-off valve 3e is closed and the pressure oil is sent under pressure to the displacement chamber 3b, the vehicle body 2, which had been about to be pushed upward by the piston 3a, is instead pushed up in the displacement chamber 3b. Pressure oil is piston 3a
Try to push down.

Therefore, due to its operation, the force applied to the vehicle system 2 in an attempt to push it up from the axle system 1 is canceled by the hydraulic energy supplied to the displacement chamber 3b, and in the end, only the axle system 1 moves upward. The vehicle system 2 is pushed up, and the vehicle system 2 becomes something that will hardly ever be pushed up.

(b) When the axle system l suddenly falls downward.

In this case as well, the switching valve 5 and the on-off valve 3e will be described in their normal state, that is, the initial state in which the switching valve 5 is set to the switching position 5B and the on-off valve 3e is set to the open position.

Due to the depression of the axle system 1, the hydraulic fluid in the displacement chamber 3b is about to be removed, and this, due to the above-mentioned case and rotation reasons, increases the working pressure in the displacement chamber 3b and causes the piston 3a, that is, the vehicle body 2, to move downward. trying to lower it to

However, in this case, the numeral 6 senses that the vehicle body 2 is about to be lowered significantly downward by the signal from the wiring 6a, and switches the switching valve 5 to the switching position 5D. Moreover, the on-off valve 3e is closed.

Therefore, the pressure oil from the hydraulic pump 5a is sent under pressure to the displacement chamber 3c via the switching valve 5, and
The hydraulic oil in is discharged to the reservoir 5b.

As a result, contrary to the above case, the hydraulic energy pumped into the displacement chamber 3c is transferred to the piston 3a, that is, to the vehicle body 2.
This forces the axle system 1 back upwards, thereby canceling out the force exerted by the axle system 1 to pull the vehicle system 2 downward.

Note that in the operations in (a) and (b) above, the on-off valve 3e does not necessarily need to be present.

That is, the displacement chambers 3b and 3C may be configured to constantly communicate with each other via the throttle channel 3d.

However, when the on-off valve 3e is present, as in (a) or (b) above, when the cylinder body 3 is operated as a hydraulic actuator, the pressure oil from the hydraulic pump 5a is displaced and acts effectively only on the displacement 43b or 3C. This makes it possible to further improve the responsiveness.

As is clear from the following explanation, the shock absorber of the present invention has the following effects.

That is, the cylinder body 3 is not only operated merely as a damper as in the conventional case, but also forcibly operated as a hydraulic actuator by the pressure oil from the hydraulic pump 5a, and the control of the operation is as follows. Since the configuration is such that the detection is performed based on the magnitude and direction of acceleration from a detector 2a fixedly installed on the vehicle system 2, even if large vibrations occur in the axle system 1, 1. The vehicle system 2 will not experience much vibration.

As a result, no matter how fast the vehicle travels, large vibrations do not occur in the vehicle system 2, regardless of the vibrations occurring in the axle system 1, so that fragile items cannot be loaded onto the vehicle. Even if you do so, you can increase the vehicle's running speed without any worries and be able to reach the destination faster and effectively utilize the maneuverability required by the vehicle. It is something that can be performed.

In addition, the operation of the switching valve 5 is performed at 4f when the vibration of the vehicle system 2 is sufficient.
When the switching valve 5 is configured to be activated only when the temperature is equal to or higher than i, the frequency of use of the switching valve 5 is reduced, so that the durability of the switching valve 5 can be improved.

Moreover, when the on-off valve 3e is interposed in the throttle channel 3d, the pressure oil from the hydraulic pump 5a is effectively used.
Even if the hydraulic pump 5a is small, the cylinder body 3 can be effectively operated as a hydraulic actuator.

[Brief explanation of drawings]

FIG. 1 shows a shock absorber as an embodiment of the present invention.
The assosorber is shown in a system diagram. The symbols used in the examples are as follows: 1: Axle system 2: Vehicle system 2a: Detector. 3 cylinder body 3a: piston, 3b and 3c: displacement chamber,
3d: Throttle channel, 3e: Onoffa, 3f Nijilinda. 4: Spring 5, switching valves 5A, 5B and 5D: Sino switching position. 5a: Hydraulic pump, 5b = reservoir. 6: Calculators 6a, 6b and 6C: Wiring. Patent applicant: Etsushi Nishikai, representative of Sanwa Seiki Co., Ltd.

Claims (1)

[Claims] ■ A spring (4) is provided between the axle system (1) and the vehicle system (2).
) and a cylinder body (3) are interposed in parallel, a detector (2a) for detecting acceleration in the vertical direction of the vehicle body is fixed to the vehicle body, and a cylinder (3f) in the cylinder body is provided. The piston (3a) is fitted with the sliding movement in the axial direction of the cylinder as "I function", and either the cylinder No. 111 or the piston is linked to the axle system No. 111,
The other of the piston or the cylinder is
The cylinder is configured to be linked to the vehicle system, and one displacement chamber (3b) and the other displacement chamber (3C) are formed above and below the piston in the cylinder, and the one displacement chamber and A throttle flow path is interposed between the other displacement chamber, and the -. side displacement chamber and the other displacement chamber are each operated by a hydraulic pump (5).
a) or a switching mechanism for selectively communicating with or closing the communication to the reservoir (5b), and the operation of the switching mechanism is configured to be operated by a signal from the small size detector described in iii. A shock absorber characterized by: 2. The switching mechanism is operated by a signal from the detector when the absolute value of the acceleration detected by the detector is less than a predetermined value, one displacement chamber (3b) and the other displacement chamber (3c) are operated.
are each connected to a hydraulic pump (5a) and a reservoir/<(5
b) When the absolute value is equal to or higher than the specified value in NII, the pressure oil from the hydraulic pump is transferred to either of the two displacement chambers or the other depending on the direction of the acceleration. 2. The shock absorber according to claim 1, wherein the shock absorber is configured such that the pressure is fed to the other displacement chamber, and the other valve opening chamber or the one displacement chamber is communicated with the reservoir. 3. The throttle channel is a channel in which an on-off valve (3e) is interposed, and the on-off valve opens the throttle channel when the acceleration detected by the detector (2a) is below a predetermined value. The shock e-absorber according to claim 2, wherein the throttle flow path is closed when the acceleration is equal to or greater than the predetermined value.