JPH10203128A - Height adjustment device - Google Patents

Abstract

(57) [Problem] To achieve a desired vehicle height adjustment by a self-pumping operation that does not require a hydraulic pump without deteriorating ride comfort, and to ensure steering stability by roll control. It is most suitable for mounting on vehicles such as automobiles. SOLUTION: A cylinder 1 for vehicle height adjustment, which is arranged between a vehicle body side and an axle side of a vehicle and expands and contracts by supplying and discharging oil to and from an internal oil chamber, slides inside the cylinder body 11. Movably housed inside this cylinder body 11
a piston 12 that defines a, and a rod body 13 that is inserted into the cylinder body 11 so as to be able to protrude and retract so that the tip is connected to the piston 12 and the base end protrudes outside the cylinder body 11. On the other hand, two suspension springs 7, 8 are arranged in series between the vehicle body B side and the axle A side via the spring receiver 9, and the spring receiver 9 is set at the free end side in the cylinder 1. The internal oil chamber a in the cylinder body 11 is connected to the reservoir (3, R) via a suction valve 4, a relief valve 5, and an on / off valve 6 which are arranged in parallel with each other. Be in communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a vehicle height adjusting device capable of adjusting the height of a vehicle body in a vehicle such as a four-wheeled vehicle.

[0002]

2. Description of the Related Art There have conventionally been various proposals for a vehicle height adjusting device capable of adjusting the height of a vehicle body in a vehicle such as a four-wheeled vehicle. In the gazette disclosed in the gazette, the following problems are pointed out.

That is, first, the hydraulic pump disclosed in the above-mentioned publication is a hydraulic pump that constitutes a hydraulic supply / discharge source for a cylinder for adjusting a vehicle height disposed between a vehicle body side and an axle side of a vehicle. It is configured to achieve a predetermined vehicle height adjustment by the supply and discharge of pressure oil by the drive of the hydraulic pump. Therefore, not only the hydraulic pump but also switches and the like for controlling the drive of the hydraulic pump are indispensable. There is a problem that the cost of the high adjustment device is easily increased.

[0004] The one disclosed in the above-mentioned publication has a problem that noise may be generated when the hydraulic pump is driven, and energy consumption accompanying power consumption, that is, fuel efficiency may be easily increased.

Further, according to the above-mentioned publication, a single suspension spring composed of a single coil spring is arranged between a cylinder connected to a vehicle body and an axle. The spring constant is the same regardless of the height of the vehicle, and therefore, even when the vehicle load is large, such as when loading luggage, roll control is not sufficient, and steering stability in the vehicle is likely to be impaired. There is a problem.

In view of the above, the proposal disclosed in Japanese Patent Publication No. 46-59, for example, is preferred in that the vehicle height can be adjusted by a self-pumping operation without using a hydraulic pump or the like. However, even with this proposal, the following problems will be pointed out.

That is, in this proposal, the pump chamber is provided in the piston rod constituting the cylinder for adjusting the vehicle height. Therefore, when oil is discharged from the pump chamber in a so-called compression stroke, the pressure is increased. The hydraulic pressure acts on the piston rod, which is a pump rod, and as a result, the reaction force of the piston rod is increased, and there is a problem that the riding comfort in the vehicle is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to not only prevent the ride comfort from deteriorating, but also to provide a self-pumping function that eliminates the need for a hydraulic pump. It is an object of the present invention to provide a vehicle height adjustment device that can adjust the vehicle height of the vehicle and can secure the steering stability by roll control, and is optimal for mounting on a vehicle such as a four-wheeled vehicle.

[0009]

In order to achieve the above object,
A vehicle height basically comprising a vehicle height adjusting cylinder disposed between a vehicle body side and an axle side of a vehicle and extended and contracted by supplying and discharging oil to and from an internal oil chamber of the vehicle. In the adjusting device, a cylinder is slidably housed in the cylinder body, and a piston for partitioning an internal oil chamber in the cylinder body. And a rod body whose base end protrudes out of the cylinder body, while two suspension springs are arranged in series between the vehicle body side and the axle side via spring supports. The spring receiver is connected to a rod body or a cylinder body set on the free end side of the cylinder, and an internal oil chamber in the cylinder body is arranged via a suction valve, a relief valve and an on / off valve arranged in parallel with each other. Liza And it becomes in communication with the server.

[0010] Preferably, the reservoir comprises a reservoir chamber connected to the cylinder body, and a suction valve, a relief valve and an on / off valve are arranged in a partition part which divides the reservoir chamber and the internal oil chamber. I do.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on the illustrated embodiment. However, even in a vehicle height adjusting apparatus according to this embodiment, as shown in FIG. A vehicle height adjusting cylinder 1 is disposed between the vehicle body B side and the axle A side and expands and contracts by supplying and discharging oil to and from the internal oil chamber a.

In the illustrated embodiment, between the vehicle body B side and the axle A side holding the tire T at the end,
A hydraulic shock absorber 2 is arranged in parallel with the cylinder 1.

To explain a little below, first, the cylinder 1
In the illustrated embodiment, the cylinder body 11 is disposed in an inverted state, is set on the fixed end side, is connected to the vehicle body B, and is slidably housed in the cylinder body 11. A piston 12 which defines an internal oil chamber a corresponding to a piston side chamber in a lever cylinder 11, and is set at a free end side, is inserted through the cylinder body 11 so as to be able to protrude and retract, and a tip is connected to the piston 12. And a rod 13 whose base end protrudes toward the axle A.

[0014] The internal oil chamber a is
In this embodiment, it is assumed that the reservoir L is communicated with the reservoir disposed outside, that is, the reservoir tank 3. At this time, the passage L is provided via the suction valve 4, the relief valve 5, and the on-off valve 6 arranged in parallel with each other. To communicate with the reservoir tank 3.

In the illustrated embodiment, the internal oil chamber a is communicated with the rod-side oil chamber b through a port 14 opened in the piston 12. The opening of the port 14 into the port 12 may be omitted, and only the internal oil chamber a may be formed.

Further, although not shown, when a damping valve is provided in the piston 12 such as by providing a restrictor in the port 14, it is possible to expect a damping action when oil passes. This is advantageous in that the arrangement of the hydraulic shock absorber 2 in parallel with the cylinder 1 can be omitted.

Further, although not shown, instead of the illustrated embodiment, in the cylinder 1, the cylinder body 11 is set to the free end side and the rod body 13 is set to the fixed end side. May be arranged in an upright state, and the rod body 13 may be connected to the vehicle body B side.

On the other hand, the suction valve 4 prevents the oil from the passage L from flowing out to the reservoir tank 3, but allows the oil from the reservoir tank 3 to flow into the passage L.

The relief valve 5 is set to release the abnormally high pressure to the reservoir tank 3 when the pressure in the passage L, that is, the internal oil chamber a communicating with the passage L becomes abnormally high.

The on / off valve 6 has a communication position 6a for communicating the passage L with the reservoir tank 3 and a passage L.
And a shut-off position 6b for shutting off communication with the reservoir tank 3 and, in the illustrated embodiment, a spring 6
The solenoid valve is set so that the switching from the communication position 6a, which is the normal position by c, to the cutoff position 6b is performed by the solenoid 6d.

As a result, it is sufficient if the on / off valve 6 is set so as to enable switching between the communication position 6a and the shutoff position 6b. Therefore, instead of using the solenoid valve shown in FIG. Of course, it may be set to be turned on and off by operation.

The solenoid 6d in the on / off valve 6
Excitation and release thereof may be performed not only by manual operation but also by a command signal from various sensors attached to the vehicle body B of the vehicle.

Therefore, when the cylinder 1 is extended and contracted, the following operation state is exhibited depending on the state of the on / off valve 6.

That is, first, when the on / off valve 6 is at the communication position 6a as shown in the figure, oil from the rod-side oil chamber b is supplied to the piston 1 when the cylinder 1 is extended.
2 flows out to the internal oil chamber a through the port 14 opened and the oil corresponding to the rejected volume integral of the rod body 13 deficient in the internal oil chamber a is replenished from the reservoir tank 3 via the suction valve 4. It takes an extended state.

The on / off valve 6 is connected to the communication position 6
During the compression operation of the cylinder 1 while staying at the position a, the oil from the internal oil chamber a flows into the rod-side oil chamber b, and corresponds to the invasion volume of the rod body 13 which becomes excessive in the internal oil chamber a. The oil flows out to the reservoir tank 3 via the on / off valve 6 and assumes a compressed state.

Next, the on / off valve 6 is switched to the shut-off position 6.
b, the oil from the rod-side oil chamber b flows out to the internal oil chamber a through the port 14 opened in the piston 12 when the cylinder 1 is extended, and the oil in the internal oil chamber a becomes insufficient. The oil corresponding to the integral of the rod body 13 that has moved out is replenished from the reservoir tank 3 via the suction valve 4 to exhibit an extended state.

On the other hand, during the compression operation of the cylinder 1 with the on / off valve 6 being switched to the shut-off position 6b, oil from the internal oil chamber a flows into the rod-side oil chamber b. Therefore, the oil corresponding to the invasion volume of the rod body 13 that becomes excessive does not flow out to the reservoir tank 3 but is in a so-called confined state, and presents a state where it cannot be compressed.

As a result, when the cylinder 1 expands and contracts with the on / off valve 6 switched to the shut-off position 6b, only oil from the reservoir tank 3 is supplied to the cylinder 1, and oil from the cylinder 1 It is not discharged to the reservoir tank 3, and therefore only the extension operation of the cylinder 1 is realized by the self-pumping action.

When the oil pressure in the internal oil chamber a becomes a so-called abnormally high pressure because the supply of oil to the internal oil chamber a of the cylinder 1 is continued by the self-pumping action, the relief valve 5 is operated. The abnormally high pressure is released, and damage to the seal portion of the cylinder 1 is prevented.

In the illustrated embodiment, two suspension springs 7, 8 are provided between the vehicle body B and the axle A.
Are arranged in series via a spring receiver 9, and the spring receiver 9 is connected to the rod body 13 of the cylinder 1.

Although not shown, when the cylinder 1 is disposed in the upright state, the spring support 9 is attached to the cylinder body 1.
Of course, it is linked to 1.

Therefore, when the cylinder 1 is in an extendable state, that is, when the on / off valve 6 is in the communication position 6
a is maintained, for example, when the axle A swings, the two suspension springs 7 and 8 expand and contract freely. However, when the on / off valve 6 is switched to the shut-off position 6b, particularly In a situation where the compression of the cylinder 1 is blocked, the compression of one suspension spring 7 which is upper in the figure is blocked, and only the compression of the other suspension spring 8 which is lower in the figure is allowed. Become.

That is, for example, when the cylinder 1 is compressed by a roll in a vehicle, only the suspension spring 8 disposed between the cylinder 1 and the axle A side is compressed, and as a result, The spring force will be higher and will be able to cope with the roll of the vehicle.

Therefore, when the load on the vehicle increases and the vehicle height decreases, the on / off valve 6
Is switched to the cutoff position 6b, the vehicle height can be gradually corrected to a high vehicle height by the self-pumping operation without the need to drive a hydraulic pump constituting a hydraulic supply / discharge source. Even if a roll phenomenon occurs when the vehicle is in a high state, the roll phenomenon can be suppressed.

When the pressure of the internal oil chamber a in the cylinder 1 becomes abnormally high due to, for example, a running vehicle riding on a projection, the relief valve 5 is actuated to eliminate the abnormally high pressure phenomenon. Become.

The on / off valve 6 is connected to the communication position 6a.
When the cylinder 1 expands and contracts in the state of being maintained, the damping action of the hydraulic shock absorber 2 is exerted, and the spring action of the two suspension springs 7 and 8 is exerted. The ride comfort in the vehicle is maintained well.

FIG. 2 shows a vehicle height adjusting device according to another embodiment. In the vehicle height adjusting device according to this embodiment, the cylinder chamber 11 has a reservoir chamber R serving as a reservoir.
And a partition housing section 15 for separating the reservoir chamber R and the internal oil chamber a from each other.
6, a suction valve 4, a relief valve 5 and an on / off valve 6 are arranged.

That is, the arrangement of the passage L in the embodiment shown in FIG. 1 is omitted. Therefore, according to this embodiment, it is not necessary to provide a separate reservoir, This is advantageous in that the entire vehicle height adjusting device can be made compact.

The rod 1 with respect to the cylinder 11
2 and the two suspension springs 7, 8 and furthermore, the function and operation of the suction valve 4, the relief valve 5 and the on / off valve 6 are not different from those of the above-described embodiment. The description is omitted.

[0040]

As described above, according to the present invention, the spring action of the two suspension springs is achieved only by switching the on / off valve without the need to drive the hydraulic pump constituting the hydraulic supply / discharge source. Of the ride comfort of the vehicle, or priority of high vehicle height adjustment by the self-pumping action can be selected.

As a result, as compared with the case where a hydraulic pump is used, the cost of the vehicle height adjusting device can be reduced, and there is no fear of generating noise and increasing fuel efficiency by driving the hydraulic pump.

According to the present invention, the two suspension springs disposed between the vehicle body side and the axle side are moved together when priority is given to riding comfort, and when the high vehicle height adjustment is prioritized. Can operate only one suspension spring, so it is possible to use different spring constants depending on the vehicle height, and in particular, corrected the vehicle height that decreased due to the increased load to a higher vehicle height Roll control in the state can be performed, and steering stability in the vehicle can be ensured.

As a result, according to the present invention, not only the desired vehicle height can be adjusted, but also the ride comfort can be achieved by the so-called self-pumping function, which obviates the need for a hydraulic supply / discharge source which requires a drive source. There is an advantage that the steering stability can be secured by roll control without deteriorating the vehicle performance, and it is optimal to be mounted on a vehicle such as a four-wheeled vehicle.

[Brief description of the drawings]

FIG. 1 is a schematic diagram partially showing a circuit diagram of a state in which a vehicle height adjusting device according to an embodiment of the present invention is mounted on a vehicle.

FIG. 2 is a longitudinal sectional view showing a cylinder according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Hydraulic shock absorber 3 Reservoir tank as a reservoir 4 Suction valve 5 Relief valve 6 On / off valve 6a Communication position 6b Shut off position 6c Spring 6d Solenoid 7,8 Suspension spring 9 Spring support 11 Cylinder body 12 Piston 13 Rod body 14 Port 15 Reservoir housing part 16 Partition wall part a Internal oil chamber b Rod side oil chamber A Axle B Body L passage R Reservoir chamber as reservoir T Tire

Claims (2)

[Claims] 1. A vehicle height adjusting device having a vehicle height adjusting cylinder disposed between a vehicle body side and an axle side of a vehicle and expanding and contracting by supplying and discharging oil to and from an internal oil chamber. A cylinder body, a piston which is slidably housed in the cylinder body and defines an internal oil chamber in the cylinder body, and which is inserted through the cylinder body so as to be able to protrude and retract, and has a tip connected to the piston. While the end has a rod body protruding outside the cylinder body, two suspension springs are arranged in series between the vehicle body side and the axle side via a spring support, and the spring support is provided. Is connected to a rod body or a cylinder body set at a free end side of the cylinder, and an internal oil chamber in the cylinder body is not connected to a reservoir via a suction valve, a relief valve and an on / off valve arranged in parallel with each other. Height adjustment device 2. A reservoir comprising a reservoir chamber connected to a cylinder body, and a suction valve, a relief valve, and an on / off valve being arranged in a partition wall for partitioning the reservoir chamber from an internal oil chamber. The vehicle height adjusting device according to claim 1,