JPH0138359Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to an air suspension whose spring constant can be changed significantly.

Conventionally, in an air suspension having an air spring, the air spring consists of a main air chamber, a sub-air chamber, and a control valve that controls communication between the two air chambers, and by controlling the control valve, the spring of the air spring is Some devices are known that are configured so that constants can be changed. In this type of air suspension,
It is known that the spring constant of an air spring can be significantly changed by increasing the number of sub-air chambers to two or more, but this is particularly true when used in automobile air suspensions. Because of the existence of the sub-air chamber, there is a problem in that it is not easy to obtain space for providing the sub-air chamber.

This idea was made in view of the above points,
Its purpose is to be able to significantly change the spring constant,
Moreover, it is an object of the present invention to provide an air suspension suitable for mounting on an automobile by arranging main and sub-air chambers efficiently in terms of space.

Hereinafter, an air suspension according to an embodiment of this invention will be described with reference to the drawings. FIG. 1 is a sectional view of the main part of the air suspension. This air suspension incorporates a shock absorber 11. The shock absorber 11 includes a cylinder (not shown) attached to the front wheel or rear wheel side, and a piston (not shown) slidably inserted into the cylinder. Further, a piston rod 12 is connected to this piston, and this piston rod 12 extends upward and is supported by a body frame (not shown) at its upper end via a mount rubber (not shown). .

By the way, a drive pin 13 is provided inside the piston rod 12, and this drive pin 13 extends in the longitudinal direction of the piston rod 12, and
It is provided so as to be slidable relative to the piston rod 12. Further, the upper end of the drive pin 13 extends further upward than the upper end of the piston rod 12, and the upper end of the drive pin 13 has a
An air cylinder (not shown) rotatably driven by the drive pin 13 is connected.

Incidentally, a first air spring chamber 14 is disposed above the shock absorber 11 and coaxially with the piston rod 12. Further, a third air spring chamber (main air spring chamber) 15 is disposed coaxially with the piston rod directly below the first air spring chamber 14. Furthermore, the third air spring chamber 1
A second air spring chamber 16 is arranged coaxially with the cylinder 11 directly below the cylinder 11 . Here, 17 indicates that when the upper wall surface of the second air spring chamber 16 rises relatively on a rough road, the third air spring chamber 15
18 is a bellows forming a part of the third air spring chamber 15, one side of which is a bump stopper for preventing damage to the wall surface, etc.
The air spring chamber 15 is attached to the side surface of the second air spring chamber 15, and the other side thereof is attached so as to surround the second air spring chamber 16. Furthermore, 19 is the piston rod 13
The third air spring chamber 1 moves up and down.
This is a seal for maintaining airtightness between the air spring chamber 5 and the second air spring chamber 16.

These air spring chambers 14 to 16 are connected to the drive pin 13
and the piston rod 12, and are connected to each other via a communication passage 20 bored across the piston rod 12, and an on-off valve 21 is interposed in the communication passage 20.
This on-off valve 21 has first to third valve parts 21a to 2.
1c. First valve part 21
a is a passage 22a bored in the piston rod 12 and communicating with the first air spring chamber 14;
A passage 22b that is bored in 3 and communicates with the communication passage 20
The first air spring chamber 14 and the communication passage 20 are connected to each other by the rotation of the drive pin 13 to control the opening and closing of the valve. It is now possible to block it.

Further, the second valve portion 21b has a passage 23a formed in the piston rod 12 and communicating with the third air spring chamber 15, and a passage 23b formed in the drive pin 13 and communicated with the communication passage 20. Similarly, by rotating the drive pin 13, the opening degree of the valve is controlled by fully aligning or partially aligning the third air spring chamber 15 and the communication passage 20. The degree of communication opening can be controlled.

Further, the second valve portion 21c has a passage 24a bored in the piston rod and communicating with the second air spring chamber 16, and a passage 24b bored in the drive pin 13 and communicating with the communication passage 20. It is configured to control the opening degree of the valve by completely aligning or partially aligning by rotating the drive pin 13, and the second air spring chamber 16 and the communication path 2
0 can be controlled.

Therefore, when the valve portions 21a to 21c are in the open mode, the first to third air spring chambers 14 to 16 are in communication with each other, so the spring constant can be made small (soft), and the valve portion 21a ~21
When c is in the closed mode, the first to third air spring chambers 14 to 16 are cut off from each other, and the spring constant is made large (hard). That is, the on-off valve 21 can be opened and closed by rotating the drive pin 13, and the spring constant can be changed by this opening and closing. In other words, since the air spring chamber is divided into three parts and all can be controlled to open and close at the same time, the spring constant can be changed more significantly than in the case of an air spring chamber with the same spring chamber capacity and one on-off valve.

Furthermore, since the second air spring chamber 16 is arranged on the cylinder 111 side of the shock absorber 11,
Compared to a case where the same spring chamber capacity as the first to third air spring chambers 14 to 16 is arranged on the piston rod 12 side, the upper wall surface of the first air spring chamber 14 can be lowered considerably below the upper end surface of the piston rod 12. can. Therefore, the upper end of the piston rod 12 can be easily attached to the vehicle body.

Next, another embodiment of this invention will be explained using FIG. 2. As shown in FIG. 2, the third air spring chamber 15 and the second air spring chamber 16 are separated by a partition plate 31. An electromagnetic on-off valve 32 is provided to switch the state of communication with the air spring chamber 16. Electrical wiring 33 passes airtightly through the third air spring chamber 15 from this electromagnetic on-off valve 32 and extends to an external control circuit (not shown).

Therefore, the first and third air spring chambers 14, 15
The communication state between the third air spring chamber 15 and the third air spring chamber 16 is controlled by rotating the drive pin 13, and the communication state between the third air spring chamber 15 and the third air spring chamber 16 is controlled by rotating the electromagnetic on-off valve 3.
By electrically controlling 2, it is possible to realize an air suspension with an optimal spring constant.

As detailed above, according to this invention, the spring constant can be significantly increased. Furthermore, since the third air spring chamber 16 is disposed on the cylinder 111 side of the shock absorber 11, when the same spring chamber capacity as the first to third air spring chambers 14 to 16 is disposed on the piston rod 12 side. In comparison, the upper wall surface of the first air spring chamber 14 can be made considerably lower than the upper end surface of the piston rod 12. Therefore, it is easy to attach the upper end of the piston rod 12 to the vehicle body.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of an air suspension according to one embodiment of the invention, and FIG. 2 is a sectional view of a main part of an air suspension according to another embodiment of the invention. 11...Shock absorber, 12...Piston rod, 13...Drive pin, 14...First air spring chamber, 15...Third air spring chamber, 16...
Second air spring chamber, 21...opening/closing valve.

Claims (1)

[Claims for Utility Model Registration] A first air spring chamber with a constant volume is provided so as to surround the piston rod of the shock absorber, and a second air spring chamber with a constant volume is provided so as to surround the cylinder of the shock absorber. an air spring chamber; a bellows is disposed between the first air spring chamber and the second air spring chamber, and a bellows is arranged between the first air spring chamber and the second air spring chamber;
a variable capacity third air spring chamber attached to the second air spring chamber so as to surround the air spring chamber; and communication between the first air spring chamber and the third air spring chamber; An air suspension comprising: a first on-off valve for shutting off communication; and a second on-off valve for communicating and blocking communication between the third air spring chamber and the second air spring chamber.