JPH0534165B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a vehicle suspension system including a main actuator and a sub actuator.

[Technical background of the invention and its problems]

2. Description of the Related Art A vehicle suspension system is known in which a cylinder contains gas and oil to provide a spring mechanism using the gas and a damping function using the oil. Regarding this type of suspension system, the present inventor previously proposed a patent application filed in 1983-
Some actuators, such as No. 42889, have a sub actuator separate from the main actuator. This device connects the gas chamber in the main actuator and the gas chamber in the auxiliary actuator with gas piping, and by installing an on-off valve in the middle of the gas piping, the effective gas chamber volume can be switched in two stages to adjust the spring constant. It is possible to change the gas chamber or increase the volume of the gas chamber. However, in this case, gas piping with difficult sealing measures must be used, and special consideration must therefore be given to gas leakage. Also,
The lower part of the cylinder in this type of suspension system is connected to parts on the tire/wheel side, such as the lower arm and knuckle of the suspension, and the axle may pass near the lower part of the cylinder, so the connection between these parts and the lower part of the cylinder is difficult. In order to avoid interference, it is better to have a thinner cylinder. Furthermore, in order to secure installation space for the suspension device, it may be convenient to have a shorter axial length.

[Purpose of the invention]

The present invention has been made based on the above circumstances, and its purpose is to be able to attach a sub actuator to the main actuator without using gas piping that is difficult to seal, and to ensure sufficient gas chamber capacity. An object of the present invention is to provide a suspension system for a vehicle in which the lower part of the cylinder can be made narrower and the length of the entire suspension system is equal to the length of the main actuator.

[Summary of the invention]

The gist of the present invention is to include a cylinder having an oil chamber inside, a hollow rod telescopically inserted into the cylinder and having an oil chamber inside and a gas chamber filled with compressed gas above the oil chamber. , a damping force generating mechanism section provided in the hollow rod and communicating the oil chamber of the cylinder with the oil chamber of the hollow rod;
A main actuator is provided, and
In a vehicle suspension system equipped with a sub-actuator having an internal gas chamber, the hollow rod upper part of the main actuator and the sub-actuator upper part are arranged parallel to each other on the underside of an integral common base, and each is airtightly attached to the common base. , and in this common base, a gas passage portion is provided which opens into both the gas chamber of the main actuator and the gas chamber of the sub-actuator and allows both gas chambers to communicate with each other.

According to the above configuration, the gas chambers of the main actuator and the sub actuator can be communicated with each other via the gas passage formed in the common base, so special gas piping is not required, which is extremely advantageous in terms of sealing. Become. It is also effective in reducing costs. Furthermore, in the suspension system of the present invention, the upper part of the hollow rod of the main actuator and the upper part of the auxiliary actuator are arranged parallel to each other on the lower surface of the integral common base and are attached to the common base. Despite having a sufficiently large gas chamber capacity with a gas chamber of nothing.

[Embodiments of the invention]

A first embodiment of the present invention will be described below with reference to FIG. The vehicle suspension system shown in FIG. 1 includes a main actuator 1 and a sub actuator 40.

First, let me explain about the main actuator 1.
In the figure, 2 indicates a cylinder. A mounting portion 4 equipped with a rubber bush 3 is provided at the bottom of the cylinder 2. This attachment part 4 is fixed to the wheel side. Further, the upper end portion 2a of the cylinder 2 is expanded, and a hydraulic seal 5 is provided inside the upper end portion 2a. Also,
A bumper lever 6 that projects upward is attached to the upper end surface of the cylinder 2.

Further, an oil chamber 7 is formed inside the cylinder 2. A bump stopper 8 is provided on the inner bottom surface of the oil chamber 7.

A hollow rod 10 is telescopically inserted into the cylinder 2. This hollow rod 10 is
The interior thereof includes an oil chamber 11 and a gas chamber 12 filled with high-pressure nitrogen gas above the oil chamber 11. Note that a float 13 may be interposed between the oil chamber 11 and the gas chamber 12. In addition, a dry bearing 1 is provided on the sliding surface between the cylinder 2 and the hollow rod 10.
4 and 15 are provided. 16 is a rebound stopper.

Further, a damping force generating mechanism section 17 is provided at the lower part of the hollow rod 10. This damping force generation mechanism section 17 includes a well-known disc valve 20, a relief coil spring 21, a constant orifice 22,
The oil chamber 7 of the cylinder and the oil chamber 11 of the hollow rod are communicated with each other.

Further, a common base 25 is airtightly attached, for example, by welding, so as to close the upper end opening of the hollow rod 10. However, this hollow rod 10
The upper end portion may be attached to the common base 25 by screwing, adhering, pressure welding, or the like.

Further, the common base 25 is provided with a mounting portion 26 for mounting on the vehicle body side. Further, a cover 27 is attached to surround the upper part of the cylinder 2 and the upper part of the hollow rod 10.

On the other hand, the sub actuator 40 includes a cylinder portion 41 with a bottom, a free piston 42 provided inside the cylinder portion 41, and a free piston 42 provided inside the cylinder portion 41.
It consists of a gas chamber 43 and an oil chamber 44 that are partitioned by a gas chamber 43 and an oil chamber 44, an oil amount control device 45 that takes oil into and out of the oil chamber 44, and the like. 46 is a seal. The oil amount control device 45 includes a hydraulic power source 47 and hydraulic switching valves 48 and 4.
9, tank 50, etc.

And the cylinder part 41 of the sub actuator
The upper end surface of the lateral extension portion 2 of the common base 25
It is airtightly attached to the lower surface of 5a by, for example, welding. A gas passage portion 55 is formed in the common base 25 to communicate the gas chamber 12 of the main actuator with the gas chamber 43 of the sub actuator. 55a is a nitrogen gas filling port;
It will be closed after filling with gas. Note that the cylinder portion 4
The upper end of 1 is screwed into the common base 25,
Alternatively, it may be attached by adhesive or pressure welding.

In the first embodiment of the device having the above configuration, a damping force is generated in the damping force generating mechanism section 17 by the hollow rod 10 expanding and contracting relative to the cylinder 2, and nitrogen in the gas chambers 12 and 43 is generated. The repulsive force of the gas acts as a spring.

In addition, if oil is put in and out of the oil chamber 44 using the oil amount control device 45, the gas chamber 44
The internal pressure or volume of the rods 2, 43 changes, and as a result, the elongation of the hollow rod 10 can be adjusted. In other words, the vehicle height can be adjusted.

According to the vehicle suspension system having the above structure, the upper end of the hollow rod 10 and the upper end of the sub actuator 40 are fixed using the common base 25, and the gas passage is formed in the common base 25. Both gas chambers 12, 4 are connected via the section 55.
3 are in communication with each other, there is no need for couplings that are difficult to seal or other special gas piping that requires gas leakage countermeasures, and it can be manufactured at low cost.

Moreover, since both the main actuator gas chamber 12 and the sub actuator gas chamber 43 function as gas springs, the spring constant can be lowered, which is effective in improving riding comfort. Additionally, the vehicle height can be easily adjusted according to changes in vehicle body load, driving conditions, etc.

Note that FIG. 2 shows a second embodiment of the present invention, and parts common to the first embodiment are given the same reference numerals and explanations are omitted, and different points will be explained below.

In this second embodiment, a gas passage opening/closing mechanism 6 for controlling the flow and cutoff of the gas passage section 55 is used.
0, and a damping force generation mechanism section 17
, an orifice flow path adjustment mechanism 61 is provided.
Both the gas passage opening/closing mechanism 60 and the orifice passage adjustment mechanism 61 are controlled by a motor 62. For more details,
Rotating shafts 63 and 64 that rotate integrally with each other protrude from both upper and lower end surfaces of the motor 62, and one of the rotating shafts 63 is connected to a rotary on-off valve 65 provided in the gas passage section 55. By changing the rotational position of this on-off valve 65, the gas passage section 5
5 can be opened and closed. In other words, when the gas passage section 55 is opened, the gas chambers 12, 43
The spring constant becomes low because the gas passages 55 are in communication with each other, and conversely, when the gas passage section 55 is closed, only the gas chamber 12 of the main actuator works, so the spring constant becomes high.

The other rotating shaft 64 extends downward and is connected to a rotary orifice opening adjustment valve 66. By changing the rotational position of the regulating valve 66, the flow passage cross-sectional area of the orifice changes, and the damping force changes. In addition, in this embodiment, when the regulating valve 66 is rotated in a direction to narrow the orifice flow path, the on-off valve 65 is simultaneously rotated in a direction to close the gas passage. 67 is motor wiring.

According to the second embodiment, for example, when the vehicle is traveling straight, the on-off valve 65 of the gas passage section 55 is opened to lower the spring constant, and the regulating valve 66 of the orifice flow path is opened to the maximum to reduce the damping force. By making it smaller, ride comfort can be improved. In addition, when turning, suddenly accelerating, stopping suddenly, or running at high speed, contrary to the above, the gas passage section 55 is shut off to increase the spring constant, and the opening amount of the regulating valve 66 of the orifice flow path is minimized to create a damping force. By increasing , steering stability can be improved.

In this second embodiment as well, the gas chambers 12 and 43 are communicated via the gas passage section 55 formed in the common base 25 as in the first embodiment, so the structure is simple and the sealing measures are easy and reliable. A suspension system with high performance can be obtained at low cost. Note that a solenoid may be used instead of the motor 62.

〔Effect of the invention〕

As described above, according to the present invention, the sub actuator can be attached to the main actuator without using gas piping that is difficult to seal. Although a sufficiently large gas chamber capacity can be obtained, the lower part of the cylinder can be configured to be thin, and the length of the entire device can be shortened, which is advantageous in terms of securing a space for installing a suspension device.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a vehicle suspension system showing a first embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a second embodiment of the present invention. 1... Main actuator, 2... Cylinder, 7
...Oil chamber, 10...Hollow rod, 11...Oil chamber,
12... Gas chamber, 17... Damping force generation mechanism section, 2
5...Common base, 40...Sub actuator,
43... Gas chamber, 44... Oil chamber, 45... Oil amount control device, 55... Gas passage section, 60... Gas passage opening/closing mechanism, 61... Orifice flow path adjustment mechanism, 6
2...Motor.

Claims (1)

[Scope of Claims] 1. A cylinder having an oil chamber inside, a hollow rod telescopically inserted into the cylinder and having an oil chamber inside and a gas chamber filled with compressed gas above the oil chamber; For vehicles equipped with a main actuator equipped with a damping force generation mechanism installed in a hollow rod and communicating the oil chamber of the cylinder and the oil chamber of the hollow rod, and a sub actuator with a gas chamber inside. In the suspension system, the upper part of the hollow rod of the main actuator and the upper part of the auxiliary actuator are arranged parallel to each other on the lower surface side of an integral common base, and each is airtightly attached to the common base, and the gas of the main actuator is installed in the common base. 1. A suspension system for a vehicle, characterized in that a gas passage section is provided that opens both inside the chamber and inside the gas chamber of the sub-actuator and allows both gas chambers to communicate with each other. 2. The suspension system for a vehicle according to claim 1, wherein an oil chamber is provided in the sub-actuator, and an oil amount control device for taking oil in and out of the oil chamber is connected to the oil chamber. 3. A gas passage opening/closing mechanism is provided in the gas passage section of the common base, and a motor for controlling opening/closing of the gas passage opening/closing mechanism is built in the main actuator. Suspension system for vehicles as described in section. 4. Claims 1 to 4, characterized in that the damping force generating mechanism section is provided with an orifice flow path adjustment mechanism, and a motor for controlling the orifice flow path adjustment mechanism is built into the main actuator. The vehicle suspension system described in any one of Item 3.