JPH06213268A - Damping device - Google Patents

Abstract

PURPOSE:To enable vibration control and posture control of a vehicle body while using a single actuator so as to obtain favorable comfortableness by communicating a pressure chamber to a pressure control valve in a control circuit, and communicating a piston side chamber to a flow control valve in the control circuit. CONSTITUTION:A pressure control valve 40 in a control circuit is set so as to control the oil pressure in a pressure chamber R1 high or low, for the purpose, oil pressure of the pressure chamber R1 is controlled to be high so as to make the controlling force large, or oil pressure of the pressure chamber R1 is controlled to be low so as to make the controlling force small, and hence vibration from the road surface can be appropriately controlled. A flow control valve 50 supplies oil from an oil pressure source P to a piston side chamber R2 of a control cylinder C, and lets flow the oil from the piston side chamber R2 to a tank T at the discharge position 55. Consequently, the control cylinders C arranged on respective four wheels of a vehicle are appropriately operated to expand or contract, the vehicle floor height for the four wheels of the vehicle can be adjusted, and as a result of this, the vehicle posture can be adjusted.

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 vibration damping device mounted on a vehicle to improve the riding comfort of the vehicle.

[0002]

2. Description of the Related Art In recent years, many vehicles have taken measures such as mounting a vibration damping device in order to improve the riding comfort while the vehicle is running. In this case, the vibration damping device is basically Is configured as shown in FIG.

That is, although the illustrated example is a railroad vehicle, it is assumed that the vehicle body 1 which constitutes the vehicle is connected to the pendulum body 3 swinging on the carriage 2 so as to draw an arc through the air suspension 4. In addition, the pendulum body 3 is connected to the carriage 2 by the cylinder 5.

The air suspension 4 includes a damper 4a.
And the gas spring 4b.

Therefore, according to this proposal, the vibrations that cause the vehicle body to move up and down are controlled by the air suspension 4, and the postures that cause the vehicle body to roll etc. are controlled by the cylinders 5. You will be able to improve your comfort.

However, in the above-mentioned conventional proposals, since the so-called actuator is composed of a plurality of air suspensions 4 and cylinders 5, there is a problem that a mechanism including a so-called control system becomes complicated.

On the other hand, in order to avoid the above-mentioned problems, although not shown, if control is performed by a single actuator, for example, a cylinder, the cylinder is controlled by the pressure of the vehicle body 1.
The vibration of the vehicle body 1 is controlled and the posture of the vehicle body 1 is controlled by the displacement control, and it becomes impossible to perform both of the control operations at the same time. As a result, effective control may not be realized.

The present invention was devised in view of the above circumstances, and an object thereof is to enable vibration control and attitude control in a vehicle body while using a single actuator, and to provide a preferable ride. It is an object of the present invention to provide a vibration damping device that is comfortable and is optimal for mounting on a vehicle.

[0009]

In order to achieve the above-mentioned object, the structure of the present invention is configured so that a control circuit expands and contracts a control cylinder having one end connected to the vehicle body side and the other end connected to the axle side. In the vibration damping device formed as described above, an outer cylinder in which the control cylinder is a member on the vehicle body side, and an inner cylinder slidably inserted into the outer cylinder via a piston continuously provided on the outer periphery thereof, A rod which is slidably inserted into the inner cylinder via a piston continuously provided at its tip to serve as an axle side member, and which is continuously connected to the outer periphery of the inner cylinder in the outer cylinder. The pressure chamber defined by the piston is connected to the pressure control valve in the control circuit, and the piston side chamber defined by the piston connected to the rod tip in the inner cylinder is the flow control valve in the control circuit. It is assumed that they are in communication.

The pressure control valve is, for example, an electromagnetic proportional pressure reducing valve, and the flow rate control valve is, for example, a servo valve or an electromagnetic proportional directional flow rate control valve, each of which is connected to a hydraulic pressure source and a tank. .

Further, a gas spring communicating with the pressure chamber is arranged in the control circuit, and further, an oil passage communicating between the pressure control valve and the pressure chamber and a fluid passage communicating between the flow rate control valve and the piston side chamber. It is assumed that a shutoff valve is provided inside each.

[0012]

Therefore, when there is no change in the hydraulic pressure in the pressure chamber and no change in the amount of oil in the piston side chamber, each chamber is in a so-called locked state and the inner cylinder slides on the outer cylinder and the rod slides on the inner cylinder. Are respectively blocked, and expansion and contraction of the control cylinder are blocked.

From this state, if only the amount of oil supplied to the piston side chamber is changed, the height position of the inner cylinder from the road surface with respect to the rod is changed, and if only the hydraulic pressure for the pressure chamber is changed, the outer cylinder with respect to the inner cylinder is changed. The height position from the road surface of is changed.

When the rod slides in the inner cylinder depending on the road surface condition, it is possible to prevent the rod from sliding on the inner cylinder by adjusting the amount of oil supplied to the piston side chamber.

Further, by adjusting the oil pressure in the pressure chamber to a high or low level, the control force for road surface vibrations via the inner cylinder can be adjusted to a high or low level.

Further, since the pressure chamber is connected to the gas spring in the control circuit, the gas spring absorbs the lift-up from the road surface via the inner cylinder.

In the fail-safe mode, it is possible to reduce the vehicle height by discharging the oil in the piston side chamber while maintaining the oil pressure in the pressure chamber with the shutoff valve.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A vibration damping device according to an embodiment of the present invention is connected to a control cylinder C and the control cylinder C as shown in FIG. And a control circuit S.

The control cylinder C is disposed on each part of the four wheels of the vehicle and is formed so that one end is connected to the vehicle body B side and the other end is connected to the axle A side, and is a vehicle body side member. An outer cylinder 10, and an inner cylinder 20 slidably inserted into the outer cylinder 10 via a piston 21 continuously provided on the outer periphery thereof.
A rod 30 that is slidably inserted into the inner cylinder 20 via a piston 31 that is continuously provided at the tip thereof and serves as an axle side member.
And.

The outer cylinder 10 has a pressure chamber R1 defined by a piston 21 connected to the inner cylinder 20, and a piston 31 connected to the rod 30 inside the inner cylinder 20.
It has a piston side chamber R2 defined by.

On the other hand, the control circuit S includes a pressure control valve 40,
The flow control valve 50 and the gas spring 60 are provided, the pressure control valve 40 communicates with the pressure chamber R1 to control the hydraulic pressure in the pressure chamber R1, and the flow control valve 50 causes the piston side chamber R to flow.
2 is connected to control the amount of oil in the piston side chamber R2, and the gas spring 60 is connected to the pressure chamber R1 so as to communicate with the pressure chamber R2.
It is supposed that the hydraulic pressure fluctuation in 1 is absorbed.

In the illustrated example, the pressure control valve 40 is an electromagnetic proportional pressure reducing valve, and the flow rate control valve 50 is an electromagnetic proportional directional flow rate control valve. However, for the flow rate control valve 50, this is a servo. It may consist of a valve.

By the way, as a concrete example, the control cylinder C is formed in a structure as shown in FIG.

That is, the outer cylinder 10 has a shaft sealing member 1 in which the upper end of the cylindrical body 11 is slidably inserted into the inner cylinder 20 at its axial center portion.
A high pressure seal 12a is sealed by 2 and a low pressure seal 13a is provided by a shaft sealing member 13 which allows the inner cylinder 20 to slidably pass through the lower end of the cylindrical body 11 at its shaft core.
It is sealed under the distribution of.

Although not shown, the outer cylinder 10 is connected to the vehicle body B side of the vehicle through an appropriate bracket member directly or indirectly connected to the shaft sealing member 12.

Next, the inner cylinder 20 is arranged so as to form a so-called double rod structure with respect to the outer cylinder 10,
The lower end of the tubular body 22 is sealed by the sealing member 23, and the lower end of the tubular body 11 is slidably inserted through the shaft core of the rod 30 by the shaft sealing member 24.
It is sealed under the distribution of 4a.

On the outer circumference of the piston 21, the outer cylinder 10,
That is, the high-pressure seal 21a that is in sliding contact with the inner circumference of the tubular body 11 is interposed.

Therefore, in the cylindrical body 11 forming the outer cylinder 10, the piston 21 connected to the outer circumference of the inner cylinder 20
A pressure chamber R1 is defined between the upper shaft sealing member 12 and a low pressure chamber R3 between the lower shaft sealing member 13 and the lower shaft sealing member 13.

The pressure chamber R1 is provided with the shaft sealing member 1 on the upper side.
2 is communicated with the pressure control valve 40 (and the gas spring 60) in the control circuit S through the through hole 12b opened to the low pressure chamber R3.
Is communicated with the tank T in the control circuit S through a through hole 11 a opened in the cylindrical body 11.

The oil leaking from the pressure chamber R1 to the upper shaft sealing member 12 side flows out to the low pressure chamber R3 side through the drain pipe 14 arranged on the outer circumference of the outer cylinder 10.

On the other hand, the rod 30 is arranged so as to form a damper structure having the inner cylinder 20 as a cylinder body, and is connected to the tip of the rod body 32 constituting the rod 30, which is the upper end in the figure. The piston 31 has a high-pressure seal 31a on its outer circumference.

Therefore, the piston side chamber R2 is defined between the upper end of the rod 30 and the upper sealing member 23 by the piston 31 connected to the tip of the rod 30 in the tubular body 22 constituting the inner cylinder 20. A low-pressure chamber R4 is defined and formed between the lower sealing member 24 and the lower sealing member 24.

The piston side chamber R2 is provided with the sealing member 2
3 is communicated with the flow control valve 50 in the control circuit S via a pipe line 23a disposed in the control circuit S, and the low pressure chamber R4 is connected to the control circuit S via a drain port 24b opened in the shaft sealing member 24. Is connected to the tank T of.

Although not shown, the rod 30 is connected to the axle A side of the vehicle through an appropriate eye member or the like provided continuously with the rod body 32.

Further, in the illustrated example, the stroke sensor 15 for detecting the displacement amount of the inner cylinder 20 with respect to the outer cylinder 10 is provided, and the stroke sensor 25 for detecting the displacement amount of the rod 30 with respect to the inner cylinder 20. Is provided.

A display 22a consisting of a shallow slit for detecting the stroke sensor 15 is provided on the outer peripheral surface of the tubular body 22 constituting the inner cylinder 20, and the stroke sensor is provided on the outer peripheral surface of the rod body 32 constituting the rod 30. A display 32a consisting of 25 shallow slits for detection is provided.

In order to ensure the operation of each of the stroke sensors 15 and 25, that is, the detection work, the outer cylinder 1
As shown in FIG. 3, a link mechanism L for preventing rotation between the two is disposed between 0 and the inner cylinder 20.

The position detected by the stroke sensor 15 is controlled by a control circuit S via a controller (not shown).
The pressure sensor is input to the pressure control valve 40 in FIG. 1 and detected by the stroke sensor 25 is input to the flow rate control valve 50 in the control circuit S via the controller.

By the way, the pressure control valve 40 in the control circuit S supplies the pressure oil from the hydraulic pressure source P to the pressure chamber R1 in the control cylinder C through the oil passage L1 and the oil from the pressure chamber R1 in the tank. It is set to flow to T, that is, the hydraulic pressure in the pressure chamber R1 is controlled to be high or low.

In the oil passage L1, gas springs 60,
A shutoff valve 70 and a pressure sensor 80 are provided, and the gas spring 60 has a damping valve 60a and is configured to exhibit the performance of a so-called passive damper.

Therefore, according to the pressure control valve 40, the pressure chamber R1 is controlled to a high oil pressure to increase the control force, and
By controlling the pressure chamber R1 to a low hydraulic pressure to reduce the control force,
Vibration from the road surface can be controlled appropriately.

In the above case, when a vibration having a large amplitude is input due to overcoming the road surface protrusion, the gas spring 60 absorbs the vibration.

The shutoff valve 70 is the solenoid 7
Communication position 72 switched by 1 and shut-off position 74 switched by spring 73
Normally, the solenoid 71 is energized to be in the communication position 72, and is switched to the cut-off position 74 when fail-safe due to a failure of the electric system or the like to secure the hydraulic pressure in the oil passage L1 and control It is set to maintain the cylinder C as a passive damper.

On the other hand, the flow control valve 50 has a shutoff position 51, a supply position 53 switched by a solenoid 52, and a discharge position 55 switched by a spring 54, and a control cylinder via an oil passage L2. Oil is supplied to and discharged from the piston side chamber R2 in C.

That is, when the flow control valve 50 is in the supply position 53, the oil from the hydraulic source P is supplied to the control cylinder C.
Supply to the piston side chamber R2 at the discharge position 5
5, the oil from the piston side chamber R2 is set to flow into the tank T.

Therefore, according to the flow rate control valve 50, when the flow rate control valve 50 is switched to the supply position 53, the oil from the hydraulic pressure source P is supplied to the piston side chamber R2 in the control cylinder C.
When it is switched to the discharge position 55, the oil from the piston side chamber R2 in the control cylinder C flows out into the tank T, and the control cylinder C can be expanded and contracted. Become.

Therefore, by appropriately expanding and contracting the respective control cylinders C provided in the respective parts of the four wheels of the vehicle, it becomes possible to adjust the vehicle height in the respective parts of the four wheels of the vehicle, and as a result, the vehicle attitude. Will be controlled.

A shutoff valve 90 is provided in the oil passage L2 under the restriction 90a. The shutoff valve 90 is closed by a solenoid 91 and a spring 93. A discharge position 94 that can be switched is provided. Normally, the solenoid 91 is energized to be placed in the cutoff position 92, and is set to be switched to the discharge position 94 at the time of fail-safe such as a failure of the electric system.

Therefore, according to the shutoff valve 90,
When this is switched to the discharge position 94, the oil in the pressure chamber R1 in the control cylinder C flows out into the tank T through the oil passage L2, and the control cylinder C is in the most contracted state, so that the vehicle The height is lowered and the running stability of the vehicle is secured.

Therefore, according to the vibration damping device formed as described above, for example, when the running vehicle travels on a sloping road surface and the vehicle body B is vertically moved, the stroke is reduced. The position detected by the sensor 15 is input to the pressure control valve 40 via the controller, and the hydraulic pressure in the pressure chamber R1 of the control cylinder C is controlled by the pressure control valve 40 so that the vibration of the vehicle body B is suppressed. It is possible to adjust the control power of the high and low.

When the running vehicle makes a sharp turn and the body B rolls, or when the front side or the rear side of the body B sinks due to a nose dive due to sudden braking or a squat due to sudden start, Sensor 25
Is detected by the flow control valve 5 via the controller.
0, and the amount of oil in the piston side chamber R2 of the control cylinder C is controlled by the flow rate control valve 50, so that the change of the vehicle body B can be suppressed.

Further, when the running vehicle gets over the road surface protrusion, it causes vibrations such as pushing up the vehicle body B. At this time, the gas spring 60 absorbs a sudden pressure change in the pressure chamber R1. As a result, the vibration that pushes up the vehicle body B does not occur.

On the other hand, when an abnormality occurs due to a so-called electric system failure or the like, the shut-off valve 70 and the flow control valve 50 are automatically switched to the shut-off positions 74 and 51 to basically prevent the expansion and contraction of the control cylinder C. At this time, the shutoff valve 90 is automatically switched to the discharge position 94.

As a result, the oil in the piston side chamber R2 of the control cylinder C flows out into the tank T via the shutoff valve 90, so that the rod 30 largely enters the inner cylinder 20 of the control cylinder C. Therefore, the control cylinder C is in the most compressed state.

As a result, the center of gravity of the vehicle body B of the vehicle is lowered, and a stable running state can be obtained, so that the vehicle can continue traveling as it is.

At this time, since the pressure chamber R1 is communicated with the gas spring 60, normal vertical vibration in the running vehicle is absorbed.

The above description has been made by taking as an example the case where the vibration damping device according to the present invention is for vibration damping in a vehicle. However, according to the configuration of the present invention, not only for a vehicle but also for a building or the like. Of course, it can also be used for damping other objects.

[0058]

As described above, according to the present invention, since the control cylinder, which is a single actuator, is configured to be expanded and contracted by the pressure control valve and the flow rate control valve, it is possible to control a plurality of actuators. In comparison, the structure of the control system is simplified and the number of members can be reduced, which has the advantages of reducing the product cost and improving the mountability on the vehicle.

[Brief description of drawings]

FIG. 1 is a diagram showing a circuit of a vibration damping device according to the present invention.

FIG. 2 is a sectional view showing a partially cutaway embodiment of a control cylinder used in the vibration damping device according to the present invention.

FIG. 3 is a partial elevational view of the same.

FIG. 4 is a schematic diagram showing a usage state of a vibration damping device as a conventional example.

[Explanation of symbols]

 A axle B vehicle body C control cylinder S control circuit R1 pressure chamber R2 piston side chamber 10 outer cylinder 20 inner cylinder 21 piston 30 rod 31 piston 40 pressure control valve 50 flow control valve

Claims (1)

[Claims] 1. A vibration damping device comprising a control cylinder, one end of which is connected to a vehicle body side and the other end of which is connected to an axle side, which is formed to be controlled to expand and contract by a control circuit. An outer cylinder, an inner cylinder slidably inserted into the outer cylinder via a piston continuously connected to the outer circumference thereof, and an inner cylinder slidable via a piston continuously connected to the tip of the inner cylinder. And a rod which is inserted into the shaft side member and which is formed in the outer cylinder by a piston continuously connected to the outer circumference of the inner cylinder, and the pressure chamber is communicated with the pressure control valve in the control circuit. The vibration damping device is characterized in that the piston side chamber defined by the piston continuously provided at the rod tip in the inner cylinder is communicated with the flow control valve in the control circuit.