JPS58184333A - Liquid-pressure shock absorber - Google Patents

Abstract

PURPOSE:To enable to adjust the height of a car and prevent a diaphragm from damage by partitioning a reservoir chamber by a cylindrical diaphragm into a liquid chamber connected to the inside of a cylinder and an air chamber connected to an air compressor. CONSTITUTION:In a reservoir chamber 9 formed between a cylinder 1 and an outer cylinder 8 around the cylinder 1, a cylindrical diaphragm 25 is fixed. By this cylindrical diaphragm 25, the inside of the reservoir chamber is partitioned into a liquid chamber 26 connected to the inside of the cylinder 1 via a bottom body 13 and an air chamber 24 connected to an air compressor and others via a supply and exhaust port 27 provided on the outer cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic shock absorber used in an air suspension of a vehicle height adjustment device or the like.

A conventional hydraulic shock absorber was constructed as shown in FIG.

That is, the cylinder 1 filled with working liquid is provided with a damping force generating means 4 consisting of a communication hole 2 on the upper and lower surfaces, which allows limited flow of the working liquid, and a valve plate 8 that completely closes the communication hole 2 at all times. A piston 5 is slidably inserted into the cylinder 1 so that two upper and lower chambers 6 and 7 are separated from each other inside the cylinder 1.
A damping force generating means is provided at the bottom of a reservoir chamber 9 formed between an outer cylinder 8 surrounding the cylinder 1, and includes a communication hole 10 on the upper and lower surfaces and a valve plate 11 that always closes the communication hole 10. 12 is in communication via a bottom body 18 having a total of 12, preferably said reservoir /
4 is enclosed, and a histone rod 15 fixed to the piston 5 projects from the top of the cylinder 1.

Note that 16 and 17 are check grates that always close the communication holes 18 and 19, respectively, and 20 and 21 are springs with a weak spring force that bias the respective check plays.

As is well known, such a hydraulic shock absorber is mounted on a vehicle by fixing the cylinder 1 on the single spring of the histone rod 15 under the spring.
During the extension stroke of the piston rod 15, the pressure in the upper chamber 6 becomes high, and the working fluid in the upper chamber 6 pushes open the valve plate 3 from the communication hole 2 and flows into the lower chamber 7 while creating a flow resistance, that is, a damping force. The liquid in the reservoir chamber 9 easily pushes open the check plate 17 through the communication hole 19 of the bottom body 18 and flows into the cylinder 1 to compensate for the withdrawal volume of the piston rod 15. On the other hand, during the compression stroke of the piston rod 15, the liquid in the lower chamber 7 pushes up the check plate 16 from the communication hole 18 of the piston b and easily flows into the upper chamber 6. The liquid pushes open the valve plate 11 from the communication hole 10 of the bottom body 13 and flows into the reservoir chamber 9 while creating a flow resistance, that is, a damping force, and the pressurized gas 14 in the reservoir chamber 9
further compress. In this way, a desired damping force is generated in the extension stroke in accordance with the operating speed of the piston rod 15.

By the way, when forming an air suspension of a vehicle height adjustment device using a hydraulic shock absorber configured as described above, the second
As shown in the figure, using a rolling diaphragm 22, one end of the rolling diaphragm 22 is attached to the piston rod 15 and fixed to the nine outer shell 28, and the other end is fully folded. Since the rolling diaphragm 22 is fixed to the outer cylinder 8 and forms part of the air chamber 24, there is a drawback that the rolling diaphragm 22 may be damaged by flying stones or the like.

The present invention has been made for the purpose of providing a hydraulic shock absorber that can be used as an air suspension for a vehicle height adjustment device without forming an air chamber using a rolling diaphragm, an outer shell, etc. As shown in the drawings from FIG. +- Attachment, #The cylindrical diaphragm 25 allows air to flow further into the reservoir chamber 9 through the liquid chamber 26 which is connected to the inside of the cylinder 1 via the bottom body 18 and the air supply/exhaust port 27 provided in the outer cylinder 8. This is because it is separated from an air chamber 24 connected to a compressor, etc.

In the embodiment shown in FIG. 8, the cylindrical diaphragm 25 has a small diameter at the center 25&, and the upper and lower ends [25b].

25c is formed into a so-called cylindrical shape with a large diameter and widening at both ends. Further, the outer cylinder 8 has an upper end side 8a provided with an air supply/exhaust port 27 having a larger diameter than the lower end part 25c of the cylindrical diaphragm 25, and a lower end side 8b having a diameter that is approximately the same as the lower end part 25c of the cylindrical diaphragm 25. It is swaged into a cylindrical shape. The lower end 25c f of the cylindrical diaphragm 25 is clamped between the outer tube 8 and the bottom body 13, and the upper end @ 25b
It is attached within the reservoir chamber 9 by being clamped between the outer cylinder 8 and the guide guide 8ρ, and the inside of the reservoir chamber 9 is separated into the inner and outer peripheries, and a liquid chamber 26 is formed on the inner periphery. , an air chamber 24 is formed around its outer periphery. However, the supply/exhaust port 2
When compressed air is supplied from 7 to the air chamber 24, the air chamber 2
4 expands and bends the cylindrical diaphragm 25 toward the liquid chamber 26 to completely increase the pressure inside the liquid chamber 26 and the cylinder. Also, when the compressed air in the air chamber 24 is removed from the supply/exhaust port 27, the cylindrical diaphragm 25 is bent toward the liquid chamber 26. The diamond 72mm 25 is bent toward the air chamber 24 side and the liquid chamber 2
6 to reduce the pressure inside the cylinder, so the air chamber 2
Concave supplying to 4.

By adjusting the amount of compressed air to fully control the internal pressure of the air chamber 24, you can freely create the Rondo reaction force calculated by the formula F=P (air chamber pressure = cage pressure) XA (Rondo cross-sectional area). becomes possible.

In the first embodiment, as described above, the cylindrical diaphragm 25 is located above the central portion 25a.

The lower ends 25b and 25a are formed into a cylindrical shape with a large diameter and both ends widen at the ends.1. Also, the outer cylinder 8 is attached to the upper end side 8a.
has a larger diameter than the lower end 25a of the cylindrical diaphragm 25, and the lower end side 8b is the lower end 2 of the cylindrical diaphragm 25.
5C, and form the BaK supply/exhaust port 27 on the upper end side of the outer cylinder 8.
When inserting the diaphragm 25 into the lower end 25c of the diaphragm 25,
completely prevents sliding contact with the inner peripheral surface of the upper end side 8a of the outer cylinder 8,
As a result, the paris 28 that occurs when drilling the supply and exhaust ports 27
This is intended to prevent the lower end 25a of the cylindrical diaphragm 25 from being damaged by the diaphragm 25, etc.

FIG. 4 shows a second embodiment of the present invention, in which an air chamber 29 is formed on the outer periphery of the outer cylinder 8 and communicates with the air chamber 24 through an air supply/exhaust port 27. Figure 29 shows the case where the number of spring legs of the shear suspension is lowered to completely improve ride comfort. Note that 80 is a spring seat, and by utilizing the spring seat 80t, the air chamber 29 is entirely formed around the outer periphery of the outer cylinder 8. Reference numeral 81 is an air supply/exhaust port that connects the air chamber 29 to an air compressor (not shown) or the like. Note that the same parts as in the prior art are given the same reference numerals and redundant explanations are omitted.

As explained above, the present invention has a piston that is completely slidably inserted into a cylinder filled with a working fluid and is equipped with a damping force generating means that allows limited flow of the working fluid. A reservoir chamber formed between the inside of the cylinder and an outer cylinder surrounding the cylinder is communicated at its bottom through a bottom body provided with a damping force generating means, and from the top of the cylinder. A hydraulic shock absorber having a protruding piston rod fixed to the piston,
A cylindrical diaphragm is installed inside the outer cylinder, and the cylindrical diaphragm further connects the reservoir chamber to a liquid chamber that is connected to the inside of the cylinder through all valves of the bottom body, and an air supply/exhaust port provided in the outer cylinder. Since all valves are separated into an air chamber connected to an air congressor, etc., the air chamber is not formed on the outside of the outer cylinder using a rolling diaphragm or outer shell as in the past. Because it accommodates a diaphragm, it has the advantage of being able to be used as an air suspension for a vehicle height adjustment device without the risk of damage to the diaphragm caused by flying stones, etc. Especially since the diaphragm is formed into a cylindrical shape.

It can be easily installed in the reservoir chamber by clamping it between the lower end outer cylinder and the bottom body or between the outer cylinder and the guide shaft.
This has the advantage that the reservoir chamber can be separated into a liquid chamber and an air chamber.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a hydraulic shock absorber, Fig. 2 is a cross-sectional view of a conventional air suspension constructed by attaching a rolling diaphragm to a hydraulic shock absorber, and Fig. 8 is a cross-sectional view of a hydraulic shock absorber of the present invention. , FIG. 4 is a sectional view of another embodiment. 1... cylinder, mounting... damping force generating means, 5...
Piston, 6, 7...Upper and lower double, 8...Outer cylinder, 9.
... Reservoir chamber, 12... Damping force generating means, 13...
・Bottom body 2 A, 15... Piston rond, 24... Air chamber, 2
5... Cylindrical diaphragm, 26... Liquid chamber, 27...
・Intake/exhaust port. Figure 2 Japanese Patent Publication No. 58-184333 (5)

Claims (4)

[Claims] (1) A damping force generating means that allows limited flow of the working fluid in a cylinder filled with working fluid.A piston with a biased surface is slidably inserted into the cylinder, and the inside of the cylinder is divided into upper and lower layers. A reservoir chamber formed between the inside and the outer cylinder surrounding the cylinder is communicated at its bottom via a bottom body provided with a damping force generating means, and is fixed to the piston from the top of the cylinder. A cylindrical diaphragm is installed in the outer cylinder, and the cylindrical diaphragm further extends the inside of the reservoir chamber and the inside of the cylinder through the bottom body under pressure of a hydraulic shock absorber made of a protruding piston rod. A hydraulic shock absorber characterized by being separated into a liquid chamber connected to an air compressor, and an air chamber connected to an air compressor or the like through an air supply/exhaust port provided in an outer cylinder. (2) The hydraulic shock absorber according to claim 1, wherein the cylindrical diaphragm has a small diameter at the center, large diameters at the upper and lower ends, and has a cylindrical shape with a force spreading outward at both ends. vessel. (3) The outer cylinder has a cylindrical shape with an upper end side having a larger diameter than the lower end part of the cylindrical diaphragm, and a lower end side having a diameter substantially the same as the lower end part of the cylindrical diaphragm. The hydraulic shock absorber according to Items 1 and 2. (4) The supply/exhaust port is provided at the upper end of the outer cylinder, which is formed to have a larger diameter than the lower end of the cylindrical diaphragm. Hydraulic shock absorber as described.