JPH0370643B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motor vehicle suspension, and more particularly to a motor vehicle suspension device with an air spring.

For this type of suspension,
- As shown in No. 60710, it is known that a desired reference vehicle height can be specified among multiple reference vehicle heights by adjusting the introduction of air into the air chamber of an air spring. . With this type of suspension, the vehicle height can be maintained at an appropriate height for driving depending on the road conditions, such as paved roads and highly uneven mountain roads, and it is possible to prevent the lower part of the vehicle from coming into contact with the road. . However, in the suspension described in the above-mentioned patent publication, when changing the vehicle height, air is introduced into the air chamber of the air spring all at once, and the vehicle height changes rapidly, making it difficult to drive on mountain roads. At times, it may become a dangerous situation.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an automobile suspension that can control an air spring so that the vehicle height does not change suddenly.

An automobile suspension according to the present invention includes an air spring having an air chamber, an air sub-tank chamber, a first passage communicating the air chamber of the variable air spring with the sub-tank chamber, and an opening/closing valve that opens and closes the first passage. , a second passage having an orifice and arranged in parallel with the first passage, and a one-way valve that allows air to flow only from the sub-tank to the air chamber of the air spring; It is characterized by comprising a third passage arranged in parallel with the passage.

In the automobile suspension of the present invention having the above-described structure, for example, by closing the first passage when driving on a rough road, the air in the sub-tank chamber can be moved one-way to the third passage due to frequent and large-amplitude movements of the vehicle body. Since the air is gradually supplied into the air chamber of the air spring through the valve, the amount of air in the air chamber increases gradually, so there is no sudden change in vehicle height, and the above-mentioned dangers are eliminated. It goes without saying that the vehicle height increases as a result of this, which is advantageous for road surface interference.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An automobile suspension according to a preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an automobile equipped with a suspension according to an embodiment of the invention. In this embodiment, the front wheel suspensions 1, 1 and the rear wheel suspensions 2, 2 are provided with accumulators or sub tanks 1A, 2A for changing the spring constants, respectively, and these are controlled by a control switch 3. It's starting to be controlled.

Next, specific examples of suspensions 1, 1 and 2, 2 will be explained with reference to FIG. The suspension code is "2" for the rear wheel.
Attach.

As shown in FIG. 2, a suspension 2 has an upper end fixed to a part 10 of the vehicle body via an elastic body 11.
A lower case 16 consists of an upper case 13 that forms an air chamber 12, and an outer cylinder 14 and an inner cylinder 15 that are assembled so that their upper ends enter and exit the lower end of the upper case.
, a connecting body 17 that airtightly connects the insides of the upper and lower cases 13 and 16, and a piston rod that coaxially penetrates the insides of the upper and lower cases 13 and 16 and is slidable up and down with respect to the inner cylinder 15 of the lower case 16. 18, a main valve 19 rotatably attached to the lower end of the piston rod 18, and a bottom valve 20 fixed to the lower end of the inner cylinder 15.
The oil chamber in the inner cylinder 15 is divided into a chamber A above the main valve 19 and a chamber B below the main valve 19, and further divided into an outer cylinder 14 and an inner cylinder 1.
The upper end of the reservoir chamber C between the chambers 5 and 5 communicates with the upper end of chamber A, and the lower end communicates with the lower end of chamber B, respectively. Further, a control rod 21 passes vertically through the center of the piston rod 18, and the upper end 21a of the control rod 21 is engaged with a rotary key 22 rotated by an external force so as to transmit rotational force. The lower end of the control rod 21 is provided with an orifice 21b that communicates with a communication hole 18b formed in the lower end 18a of the piston rod 18 so as to communicate chamber A and chamber B. Due to the rotation, this orifice 21b and the piston rod lower end 18a
Communication with the communication hole 18b is turned on and off.

The details of the structure of the lower end of the piston rod 18, including the lower end of the control rod 21, the main valve 19, and the bottom valve 20 will be omitted.

The relative vertical movement of the upper case 13 and the lower case 16 is caused by the spring 30 held between the upper and lower spring cases 13a and 16a fixed to the upper and lower cases 13 and 16, in addition to the air spring provided by the air chamber 12. be absorbed. Brackets 16b and 16c fixed to the outer surface of the lower case 16 are for fixing a wheel support structure including a wheel hub that rotatably supports the wheels, so that the wheels can move up and down on the part 10 of the vehicle body. is maintained.
That is, the vehicle body is suspended by wheels and elastically supported so as to be movable up and down.

A part of the peripheral wall of this air chamber 12 has an opening 12a.
is provided, and one end of a pneumatic pipe 23 for communicating the accumulator 2A and the air chamber 12 is connected to this opening 12a. This air pipe 2
3, air is supplied from the accumulator 2A to the air chamber 12 via this air piping 23, or from the air chamber 12 to the accumulator 2A.
An air flow control mechanism 31 is provided for controlling the discharge of air to. Next, the configuration of the air circulation control mechanism 31 will be explained with reference to FIG.

The air control mechanism 31 includes first, second, and third passages 32, 33, and 34 arranged in parallel with each other. The first passage 32 is provided with an on-off valve 35 that is an electromagnetic valve operated by an actuator 35a that is a solenoid. Second
The passage 33 is provided with an orifice 36 that limits the flow rate of air flowing through the passage. The third passage 34 includes air chamber 1 from the accumulator 2A.
One-way valve 3 that only allows air to flow to 2
7 is provided. The actuator 35a of the on-off valve 35 is connected to the power source S via the changeover switch 3.

Next, the operation of the suspension constructed as described above will be explained with reference to FIG.

In a normal state, air flows between the accumulator 2A and the air chamber 12 via the first, second, and third passages 32, 33, and 34. When the changeover switch 3 is turned on when the road becomes rough, the actuator 35a is energized, so the on-off valve 35 closes the first passage 32. When the car drives on rough roads in this state, the suspension repeatedly expands and contracts. When the suspension is extended, the air chamber 12 becomes a negative pressure, so the air chamber 12 is connected to the second and third passages 3 from the accumulator 2A.
Air is supplied via 3 and 34. On the other hand, when the suspension contracts, the pressure in the air chamber 12 increases, so the air in the air chamber 12 is
However, since the third passage 34 is provided with the one-way valve 37 as described above, the air flows into the accumulator 2A through the third passage 34. Therefore, it flows into the accumulator 2A only through the second passage 33. However, since the second passage 33 is provided with an orifice 36, air only gradually flows into the accumulator 2A. As described above, when the vehicle is traveling on a rough road, vertical movements of the vehicle body with large amplitudes occur frequently, so the air chamber 12 is gradually filled with air, and the vehicle body is also gradually raised. Furthermore, as described above, the speed and amount of air increase in the air chamber 12 are proportional to the frequency of vertical movement of the vehicle body, so the vehicle height is naturally determined according to the road conditions. Furthermore, even if the switch 3 is erroneously operated while driving on a flat road, there is almost no vertical movement of the vehicle body, so sudden changes in vehicle height are less likely to occur.

In the above embodiment, an on-off valve 35 is provided in the first passage 32 and an orifice 36 is provided in the second passage 33. However, as shown in FIG. 4, an orifice is provided on the shutoff side of the valve 35. By doing so, the second passage can be omitted, and
A double-acting solenoid valve may be used as the on-off valve, or a manual valve may also be used.
Furthermore, the switch 3 may be controlled manually or automatically.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an automobile equipped with a suspension according to an embodiment of the present invention, FIG. 2 is a sectional view showing an example of a spring means used in the suspension of the present invention, and FIG. FIG. 4, a system diagram of the embodiment of the suspension of the present invention, is a diagram showing a modification of the main part of the system diagram shown in FIG. 3. 1, 2... Suspension, 1A, 2A... Accumulator, 3... Changeover switch, 12...
Air chamber, 32...first passage, 33...second passage,
34...Third passage, 35...Opening/closing valve, 36...Orifice, 37...One-way valve.

Claims (1)

[Claims] 1 An air spring provided with an air chamber, an air sub-tank chamber, a first passage communicating the air chamber of the air spring with the sub-tank chamber, an opening/closing valve for opening and closing the first passage, and an orifice; a second passage arranged in parallel with the passage, and a one-way valve that only allows air to flow from the sub-tank to the air chamber of the air spring, and a third passage arranged in parallel with the first and second passages. A car suspension with a passageway.