JPH04115911U - Hydraulic pneumatic suspension device for vehicles - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the response of attitude control when rolling occurs due to cornering of a hydropneumatic suspension. [Structure] The piston 31 of the double-acting hydraulic cylinder 30 moves as the steering wheel 28 is operated. At this time, due to the action of the orifice 34, a pressure difference is generated between the oil chambers 32 and 33 according to the steering speed, which is transmitted to the oil chambers 24 and 25 of the sub-spool valve 21, and is transmitted to the oil chambers 24 and 25 of the sub-spool valve 21.
23 moves against the centering spring 26 or 27,
Controls oil supply and drainage of the strut cylinder 2. After that, as time passes, the pressure difference between the oil chambers 32 and 33 disappears, and the spool 23 of the sub-spool valve 21 returns to the neutral position.
Before that, attitude control using the existing spool valve 11 has started.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a hydropneumatic suspension device for a vehicle.

0002

[Conventional technology]

Conventionally, this type of suspension device is disclosed in Japanese Utility Model Application Publication No. 64-52919. There are some things disclosed in . The configuration of this suspension device is shown in FIG. 2 and will be briefly described. In the figure, a strut cylinder consisting of a hydraulic cylinder is installed on the body frame 1 side. 2 and an accumulator communicating with the strut cylinder 2 via an orifice 3. A hydro-pneumatic suspension consisting of a gas spring 4 is provided as a main body. One end is pivotally supported by a bracket 5 fixed to the frame 1, and a wheel 6 (not shown) is located in the middle. The other end of the arm 7 connected to the axle is connected to the piston rod of the strut cylinder 2. By supporting the shaft at the end of the wheel, a hydraulic and pneumatic suspension is created between the body frame 1 and the axle. intervention. In addition, the strut cylinder 2 and an oil tank or an oil tank (not shown) are also included. The spool valve 11 installed in the oil supply and drainage pipes 8, 9, and 10 connecting to the oil pump One end of the spool 13 that is slidably inserted into the valve body 12 and the intermediate portion of the arm 7 and a rod 17 with a shock absorber 16 made up of a spring 14 and a damper 15 interposed therein, and the intermediate part is pivotally supported. It is connected via a link mechanism with an L-shaped link 19 having a pendulum 18 at one end. Ru. The above-mentioned configuration is provided for each of the front, rear, left and right wheels.

0003 Next, the operation of the suspension device having such a configuration will be briefly described. When the vehicle is at the standard height position, the spool valve 11 is in the neutral position as shown in Figure 2. The oil supply and drainage pipes 8, 9, and 10 are isolated from each other. From this state, for example, the vehicle height As it becomes lower, the distance between the vehicle body side and the axle side becomes narrower, and the arm 7 rotates counterclockwise in the figure. Dynamically displaced, the L-shaped link 19 rotates counterclockwise in the figure via the rod 17. This is it , the spool 13 moves inside the valve body 12 to the left in the figure and connects to the oil pump side. The oil supply and drainage pipe 10 connected to the strut cylinder 2 and the oil supply and drainage pipe 8 connected to the strut cylinder 2 are connected. Strut cylinder 2 is refueled and the piston is pushed down to raise the vehicle height. .

0004 In addition, if the vehicle height becomes higher, the operation will be the opposite of the above, and the connection to the oil tank side will occur. The oil supply and drainage pipe 9 connected to the strut cylinder 2 and the oil supply and drainage pipe 8 connected to the strut cylinder 2 are connected to the spool. Connected through valve 11, oil is drained from strut cylinder 2 and the vehicle height is increased. Descend. According to the hydropneumatic suspension system with such a configuration, the vehicle height remains unchanged even if the load capacity changes. In addition to being able to hold the oil constant, the spool valve on the front wheel operates to refuel when braking. The spool valve on the rear wheel side drains oil and suppresses nose dive. Also, turning Sometimes the outer spool valve operates to refuel and the inner spool valve operates to drain. It also has the effect of suppressing rolling.

[0005]

[Problem that the idea aims to solve]

However, in the conventional hydropneumatic suspension device, the spool valve 11 is When the pool 13 moves more than a predetermined stroke, in other words, the vehicle height displaces more than a predetermined amount. When this happens, the vehicle body attitude control function by the spool valve 11 begins to operate. others Therefore, after pitching or rolling occurs, attitude control by spool valve 11 is There is a time delay before it starts.

[0006] This invention was developed in view of the above circumstances, and is particularly designed to prevent rolling of vehicles. The objective of the present invention is to provide a hydropneumatic suspension system for vehicles that can improve the responsiveness of force control. purpose.

[0007]

[Means to solve the problem]

For this reason, the present invention provides a hydraulic cylinder and an axle installed between the vehicle body frame and the axle. A hydropneumatic suspension consisting of a cumulator and a connection to the hydropneumatic suspension. A spool that is installed in an oil supply and drainage pipe and has a spool that controls opening and closing of the oil supply and drainage pipe. a pool valve, and the spool of the spool valve provided on the vehicle body side and the axle side are connected via a link mechanism, and the spool moves in response to displacement between the vehicle body and axle. A vehicle hydropneumatic suspension system configured to open and close oil supply and drainage piping. the piston that responds to steering operation and the oil chambers on both sides of the piston. A double-acting hydraulic cylinder with a throttle mechanism that communicates with the valve body is provided, while a The spool is slidably housed and hydraulic pressure for spool operation is generated on both sides of the spool. each oil chamber, and each chamber housed in each oil chamber to elastically hold the spool in a neutral position. A sub-spool valve equipped with an interfering spring is provided, and the sub-spool valve is Each oil chamber of the lubricant is communicated with the corresponding oil chamber of the double-acting hydraulic cylinder, and , oil supply and drainage piping with a sub-spool valve bypassing the spool valve. The structure is such that it is interposed in the

[0008]

[Effect]

In such a configuration, when the steering wheel is turned, the piston of the double-acting hydraulic cylinder The piston moves in accordance with the steering direction, and the throttle mechanism moves the oil between the oil chambers on both sides of the piston. A pressure difference occurs depending on the rudder speed. This pressure difference is caused by the oil chamber of the sub-spool valve. As a result, the spool of the sub-spool valve moves against the centering spring. do. This movement comes into play when the vehicle height changes more than a predetermined amount due to rolling. Faster spooling than existing spool valves. Therefore, the rotation caused by cornering Attitude control by the hydropneumatic suspension begins before the ringing occurs. So After that, as time passes, the pressure difference between the oil chambers of the double-acting hydraulic cylinder disappears, and the sub The spool of the spool valve receives the elastic force of the compressed centering spring. and return to the neutral position, but by then the existing spool has moved more than a predetermined stroke. In this way, oil supply and drainage of the hydraulic cylinder is controlled.

[0009]

【Example】

Hereinafter, one embodiment of the present invention will be described based on the drawings. In addition, the same elements as before The same reference numerals are used to omit the explanation. In FIG. 1 showing this embodiment, a conventional spool valve 11 is bypassed and provided. The sub-spool valve 21 is slidably housed in the valve body 22 and has three parts in the middle. The spool 23 has three small diameter portions 23a, 23b, and 23c formed thereon, and the Each oil chamber 24, 25 is used to generate hydraulic pressure for pool operation, and the oil chambers 24, 25 housed in Each center elastically holds the spool 23 in a neutral position when both oil chambers 24 and 25 are at equal pressure. It is configured with springs 26 and 27. Then, the spool 23 is When in the upright position, it branches from the oil supply and drainage pipe 9 that connects to an oil tank (not shown). Separated from the oil supply and drainage pipe 9a connected to the oil supply and drainage pipe 10 connected to the oil pump (not shown). The branched oil supply and drainage pipe 10a and the oil supply and drainage pipe connected to each strut cylinder 2 on the left and right sides of the vehicle. The pipes 8a and 8'a are cut off from each other. Also, the spool 23 is moved to the left from the neutral position. When the vehicle moves to the right, one of the strut cylinders 2 on the left and right of the vehicle One side is connected to the oil tank side and the other side is connected to the oil pump side. ing.

0010 In addition, the double-acting hydraulic cylinder 30 is connected to the steering wheel 28 via a rack and pinion mechanism. The piston 31 has oil chambers 32 and 33 on both sides connected to each other. An orifice 34 is formed as a diaphragm mechanism for passing through. And this double acting hydraulic One oil chamber 32 of the cylinder communicates with the corresponding oil chamber 24 of the sub-spool valve 21. The other oil chamber 33 communicates with the corresponding other oil chamber 25 of the sub-spool valve 21. ing.

[0011] Next, the operation will be explained. Here, an example will be explained in which the vehicle turns to the right. For example, when the vehicle body is at the standard vehicle height position and the spool of spool valve 11 is 13 and the spool 22 of the sub-spool valve 21 are both in the neutral position, When the steering ring 28 is steered in the direction of arrow A in the figure (right turn), the outer side of the vehicle (in this case, the vehicle The left side sinks and the inside side (in this case, the right side of the vehicle) rises. Therefore, the hydraulic and pneumatic pressure on the left side of the vehicle In suspension, the arm 7 is rotated in the counterclockwise direction (direction of arrow B) in Fig. 1 and connected to the L-shaped link via rod 17. 19 rotates counterclockwise (direction of arrow C) in FIG. This allows the main spool to The valve 13 starts moving inside the valve body 12 in the left direction (direction of arrow D) in Fig. When the strut is installed, the oil supply and drainage pipe 10 connected to the oil pump side and the strut cylinder The oil supply and drainage piping 8 connected to the cylinder 2 communicates with the strut cylinder 2 to supply oil to the strut cylinder 2. Push down the piston of the rat cylinder 2 to raise the vehicle height. At this time, the spout Before the spool 13 of the steering wheel valve 11 moves a predetermined stroke, the steering wheel 28 is In response to the steering, the piston 31 of the double-acting hydraulic cylinder 30 moves to the left in the figure (in the direction of arrow E). Moving. At this time, the piston 31 is placed between the oil chambers 32 and 33 due to the action of the orifice 34. A pressure difference occurs depending on the moving speed of the steering wheel 28, that is, the steering speed of the steering wheel 28, and the oil chamber 32 side The pressure becomes higher from the oil chamber 33 side. Then, the pressure difference that occurs is caused by the oil in the sub-spool valve 21. The spool 23 is transmitted to the chambers 24 and 25 against the elastic force of the centering spring 27. Move to the right in the figure and connect the bypass oil supply and drainage pipe 10a that connects to the oil pump and The oil supply and drainage pipe 8a connected to the rat cylinder 2 communicates via the central small diameter portion 23a. Ru. As a result, the oil pump supplies oil to the strut cylinder 2 and the strut Push down the piston of cylinder 2 to raise the vehicle height. Then, over time As a result, the pressure difference between the oil chamber 32 and the oil chamber 33 disappears, and the sub-spool valve 21 The pressure difference between the oil chambers 24 and 25 disappears, and the elastic force of the compressed centering spring 29 In response to this, the spool 23 returns to the neutral position and blocks the oil supply and drainage pipes 10a and 8a. During this period, as mentioned above, the spool 13 of the spool valve 11 moves over a predetermined stroke. As before, the oil supply and drainage pipes 10 and 8 are connected and supply to the strut cylinder 2. Oil continues to flow and raises the vehicle height.

0012 Also, the spool 23 of the sub-spool valve 21 moves and connects the oil supply and drainage pipes 10a and 8a. When connected, the supply/discharge port connected to the oil tank via the sub-spool valve 21 Oil supply and drainage pipe connected to the oil pipe 9a and the strut cylinder (not shown) on the right side of the vehicle. Pipe 8'a is connected and oil is drained from the strut cylinder on the right side of the vehicle, lowering the vehicle height. lower. Note that when the vehicle is steered to the left, the operation is opposite to the above.

[0013] According to this configuration, the oil supply and drainage control of the strut cylinder 2 is performed in synchronization with the steering of the vehicle. control has started, so there are steps to suppress rolling even before rolling occurs. Attitude control will be performed, and the delay time of attitude control for rolling will be significantly reduced. It can be shortened to

[0014]

[Effect of the idea]

As explained above, according to the present invention, the hydraulic and pneumatic suspension is operated almost simultaneously with the steering operation of the vehicle. Since the oil supply and drainage operation of the hydraulic cylinder of the steering wheel starts, the rotation caused by cornering will be reduced. Attitude control can be started earlier than before when ringing occurs, reducing delays in attitude control. It can save you a lot of time.

[Brief explanation of drawings]

[Figure 1] Main part configuration diagram of an embodiment of the present invention

[Figure 2] Main part configuration diagram of conventional example

[Explanation of symbols]

1 Body frame 2 Strut cylinder 4 Gas spring 7 Arms 8a to 10a Oil supply and drainage pipes 11 Spool valve 12 Valve body 13 Spool 17 Rod 19 L-shaped link 21 Sub-spool valve 23 Spools 24, 25 Oil chamber 26, 27 Centering spring 28 Steering 30 Double acting hydraulic cylinder 31 Piston 32, 33 Oil chamber 34 Orifice

Claims (1)

[Scope of utility model registration request] Claim 1: A hydropneumatic suspension that is interposed between a vehicle body frame and an axle and is composed of a hydraulic cylinder and an accumulator, and an oil supply and drainage pipe that is interposed in an oil supply and drainage pipe that is connected to the hydropneumatic suspension. A spool valve having a spool for opening and closing control is provided, the spool of the spool valve provided on the vehicle body side and the axle side are connected via a link mechanism, and the spool moves in response to displacement between the vehicle body and the axle. In a vehicle hydropneumatic suspension system configured to open and close oil supply and drain piping, a double-acting hydraulic cylinder includes a piston that responds to steering operation and a throttle mechanism that communicates between oil chambers on both sides of the piston. a spool slidably housed within the valve body;
A sub-spool valve is provided on both sides of the spool, and includes oil chambers that generate hydraulic pressure for operating the spool, and centering springs that are housed in the oil chambers and elastically hold the spool in a neutral position. A vehicle characterized in that each oil chamber communicates with a corresponding oil chamber of the double-acting hydraulic cylinder, and a sub-spool valve is interposed in an oil supply/drainage pipe provided by bypassing the spool valve. Hydraulic pneumatic suspension equipment.