JPS59171709A - Vehicle height adjuster - Google Patents

Abstract

PURPOSE:To reduce a spring constant and prevent the joint part of an oil feed pipe from showing any looseness and other troubles in the titled equipment which applies gas and oil pressure by communicating each of the gas chambers of a main actuator and a sub actuator having oil chambers each to which a hydraulic unit is connected. CONSTITUTION:If the oil pressure in a power steering unit 36 is below a specified value, opening and closing valves 27 and 28 are opened to communicate the gas chambers 8 and 23 of each pair of main and sub actuators 1, 2, 20 and 21 with each other. Since the capacities of the gas chambers become great, the spring constant may stay low and the riding on a vehicle be therefore comfortable. Once each rod 6 is forced down due to increased load to actuate a limit switch 13, direction change-over valves 33 and 34 operate so that pressure oil is fed into each of the oil pressure chambers 24 of the sub actuators to compress the gas chambers 24. Consequently, the rods 6 are stretched to maintain the vehicle at a constant height. When the oil pressure in the unit 36 is increased by turning a steering wheel, the valves 27 and 28 are closed so that the main actuators 1 and 2 only are operated, hence increasing the spring constant. As a result, the riding feel may be improved and troubles such as looseness of the joint part be prevented.

Description

[Detailed description of the invention] This invention relates to a vehicle height adjustment device that allows the height of the vehicle to be adjusted.

Conventionally, this type of device had an actuator consisting of a cylinder part and a rod part filled with oil and high-pressure gas, and the height of the rond part was changed by moving oil in and out of the actuator. Not only can the vehicle height be adjusted, but the repulsive force of the high-pressure gas can also provide a suspension function. The above-mentioned actuator is a flexible suspension whose spring constant is determined by the pressure of the gas enclosed and the volume of the gas chamber; for example, the larger the volume of the gas chamber, the smaller the spring constant.

By the way, when this type of vehicle height adjustment device is provided in the suspension mechanism of a vehicle body, the ride comfort is generally good if the spring constant is low. However, in conventional actuators, the volume of the gas chamber may be insufficient, resulting in poor riding comfort. Moreover, in the case of the conventional vehicle height adjustment device, it is necessary to connect the oil pipe to the actuator of the suspension mechanism, which is subject to strong vibrations, and there is a risk of problems such as loosening of the joint and oil leakage.

The present invention was made based on the above circumstances, and its purpose is to reduce the spring constant, and also to place the connection part of the oil pipe to the actuator in a place that is less susceptible to vibrations. The purpose of the present invention is to provide a vehicle height adjustment device.

In other words, the present invention comprises a main actuator that includes an oil chamber, a gas slag, an orifice, etc. inside a cylinder part and a rod part, a sub actuator that has an oil chamber and a gas chamber inside, and a main and sub actuator. This vehicle height adjustment device is characterized by comprising a gas passage connecting the gas chambers and a hydraulic unit connected to the sub-actuator.

In the present invention configured in this way, the gas chambers of the main actuator and the sub actuator are communicated through the upper aB gas connection, so the volume of the entire gas chamber is large and the spring constant can be lowered. I can do it.

Moreover, according to the above configuration, the oil pipe for taking oil in and out can be easily connected to the sub-actuator, and the sub-actuator can be installed at a position away from the suspension mechanism of the vehicle body. It can reduce the effects of vibrations applied to joints, etc., and is also effective in preventing joints from loosening and oil leakage.

A first embodiment of the present invention will be explained below with reference to FIG. In the figure, 1 and 2 are a pair of left and right main actuators. These main actuators 1.2 are arranged, for example, in the left and right suspension mechanisms that support the front wheels of an automatic M.
The main actuator 1'5r is represented by Akira Shima.

That is, 3 is a cylinder part, and an oil chamber 4 is formed inside this cylinder part 3.

This cylinder portion 3 is attached to, for example, a member on the axle side via a support portion 5'f. 1. A rod portion 6 is inserted into the cylinder portion 3 so as to be movable in the vertical direction. This rod portion 6Fi is hollow, and a free piston 7 is housed inside the rod portion 6Fi so as to be slidable in the vertical direction. And this f-
A gas chamber 8 is formed on the upper side of the Lee piston 7, and an oil chamber 9 is formed on the lower side, and an orifice 11 is formed in a piston-shaped portion 10 on the lower side of the oil chamber 9. Incidentally, the upper end portion 12 of the rod portion 6 is designed to be attached to a member on the outer frame side, for example. The rod portion 6 also has a pair of upper and lower limit switches 7, ? , 1
4 is additionally installed, and the relative roughness of the rod part 6 with respect to the cylinder part 3 can be detected.

The output signals from the limit switches 13 and 14 are input to a controller 15 using a microconbeater.

A pair of auxiliary actuators 20.21 are provided to pair with the main actuator 1.2. These sub-actuators 2 (1, 21 are each equipped with a free piston/22', 22 that is movable in a circular part, and a gas chamber 2 is located on the upper side in the drawing with the free piston 22, 22 as a boundary).
,? , 23, and oil chambers 24, 24 are formed at the lower side in the figure.

The gas chamber 8.8 of the main actuator and the gas chamber 23.23 of the auxiliary actuator are connected by gas passages 25.26 using high-pressure gas pipes or the like, respectively. Frost and magnetic on-off valves 27 and 28 are provided in the middle of each gas passage 25 and 26.

Furthermore, a gate valve 29 is installed between each gas passage f1i5.25.26.
is provided. The on-off valves 27 and 28 and the gate valve 29 are controlled to open and close according to an output signal from the controller 15.

Further, the oil chamber 24 of the sub-actuator 20, 21,
A hydraulic unit 30 is connected to 2.4. This hydraulic unit 30 is an oil feeder 3).

32, a pair of directional control valves 33, 34, and a hydraulic pressure generation source 3
5, a controller 15, etc., the oil chamber 2 is controlled by switching the directional control valves 33, 3.4.
Pressure oil can be put in and taken out at ports 4 and 24.

The controller 15 also includes a power steering unit 36.
The hydraulic pressure signal is inputted.

In the first embodiment configured as described above, when the oil pressure of the power steering unit 36 is below a predetermined level, such as when driving straight, the on-off valves 27 and 28 are opened as shown in FIG. . Therefore, in this state, the gas chamber 8 of the main actuator and the gas chamber 23 of the auxiliary actuator communicate with each other, and the volume of the gas chamber is widened, so that the spring constant does not decrease and a good riding comfort is obtained.

In addition, when the vehicle body load is large, the rod portion 6,
When 6 is pressed down by more than a predetermined value, limit switch 1
3.13 detects this and sends a signal to the controller 15, which operates the directional control valves 3.3 and 34 to control the sub actuator. Pressurized oil is sent to the outlet chamber 24.24 to compress the gas in the gas chamber 23.
6 can be extended to maintain a constant vehicle height. Also,
On the other hand, when the iron parts 6, 6 extend to a height exceeding a predetermined amount under light loads, the other 1-nomit switch 14, 14
detects this and sends a signal to the control valve 11 and valve 15, which operates the directional control valves 33 and 34 in the opposite direction to the upper direction, thereby draining the oil in the oil chambers 24 and 24. As a result, the p-rod portions 6, 6 are lowered to a specified height, and the revision can be kept constant.

Furthermore, when the white rad parts 6, 6 move up and down due to unevenness of the road surface, oil flows through the orifices 11, 11, and a damping effect can be obtained.

Note that the gate valve 29 is normally closed as shown in FIG. 1 to block the gas flow f/f, 25, 26 from each other, and by doing so, the heights of the left and right actuators can be adjusted separately. be able to.

Therefore, the vehicle height can always be kept constant even if the weight B on the left and right sides of the rack body differs due to, for example, shifting of the load. It's a trench, open the gate valve 29 and remove all the gas chambers 8.
8, 2,? , 2,? When communicating,
The gas chamber volume is maximized and the spring constant can be further reduced.

However, this gate valve 29 is not necessarily necessary;
Even if both gas passages 25 and 26 cannot be communicated with each other, the objective of period b of the present invention can be achieved.

On the other hand, when the driver performs a steering operation such as when changing lanes while driving, the oil pressure of the power steering unit 36 increases.

In the present embodiment, however, this oil pressure increase is detected and a signal is sent to the controller 15 to close the on-off valves 27 and 28. By doing this, the gas chamber 8 of the main actuator and the gas chamber 23 of the sub actuator are partitioned, and as a suspension, the gas chambers 8, 8 of the main actuator are separated.
only those who will be working will have to work. Therefore, the repulsion constant is high,
This ensures vehicle stability when changing lanes or making curves.

FIG. 2 shows a second embodiment of the present invention, which differs from the first embodiment in that the sub actuator and the directional control valve are integrated into one. Note that parts common to those in the first embodiment are given the same reference numerals, and explanations thereof will be omitted.

That is, this second embodiment includes one actuator 40, and the gas chamber 23 of this sub-actuator 4θ is connected to the on-off valves 27 and 28 via the gas passage 41'f. Further, a directional switching valve 43 is connected to the oil chamber 24 of the sub actuator 40 via an oil feed pipe 42 .

Also, a limit switch J is installed near the stabilizer 45.
,? , J4 is provided, stabilizer 45
The vehicle height is determined by detecting the height of the center of the vehicle.

In the second embodiment of the above configuration, the spring constant is similar to that described in the first journey example.
By opening 28 and putting the gas chambers 8.8.23 in communication, the volume of the gas chambers can be increased. On the other hand, in order to increase the spring constant, the gas chambers 8, 8 are separated by closing the on-off valve 27.2'8.

Also, when the vehicle height changes due to a change in load, etc., the limit switch 13 or 1
4 is activated. Then, as in the first embodiment, the switching valve 43 is operated to move the rod 6.6 up and down, thereby keeping the vehicle height constant.

According to the second embodiment, the structure is relatively simple because only one sub actuator 40, one switching valve 43, etc. are required.

In each of the above embodiments, the on-off valves 27 and 28 are switched by detecting the hydraulic pressure of the power steering unit 4, or the on-off valves 27 and 28 are switched manually or based on other input signals. f' [ may be made.

Furthermore, for vehicles not equipped with a power steering wheel, a system may be used in which the steering wheel angle or steering wheel rotation angular velocity is detected.

Furthermore, the off-shore speed, brake, and axle 51 are detected, and as described above, according to the present invention, the spring constant can be lowered by communicating the gas chambers of the main actuator and the sub actuator through the waste passage. , can improve riding comfort.

Furthermore, by connecting the hydraulic unit to the sub-actuator, it is possible to place the connection portion of the oil pipe to the actuator in a location that is less likely to be affected by vibrations.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing a first embodiment of the present invention, and Fig. 2 is a system diagram showing a second embodiment of the invention. 4...Aburane, 6
... Rod portion, 8... Gas chamber, 11... Orifice, 15... As controller, 20, 21... Sub-actuator, 23... Gas chamber, 24... Oil chamber, 25. 26
...Gas passage, 27.28...Opening/closing valve, 30...
Hydraulic unit, 36... Power steering unit, 40... Sub-actuator.

Claims (2)

[Claims] (1) A main actuator comprising a cylinder part and a rod part inserted into the cylinder part and having an orifice; a main actuator having an oil chamber and a gas chamber therein; and a sub actuator having an oil chamber and a gas chamber therein; A vehicle height adjustment device characterized by comprising: a gas passage that interconnects the force chamber of the main actuator and the force chamber of the auxiliary actuator; and a hydraulic unit connected to the oil chamber of the auxiliary actuator. . (2) The vehicle height adjusting device according to claim (1), wherein the gas passage is configured to include a closing valve in the middle thereof.