JPH08145107A - Damping force adjusting type hydraulic shock absorber - Google Patents

Abstract

PURPOSE: To provide a hydraulic shock absorber of damping force adjusting type, whose damping force adjusting mechanism is located at the side of a cylinder and with which the installation is facilitated. CONSTITUTION: An inner cylinder 15 and an outer cylinder 16 are installed on the outside of a cylinder 14 so that a ring-shaped path 17 and reserver chamber 18 are provided. A piston 19 coupled with a piston rod 20 is fitted in the cylinder 14. Through the path 17 the upper chamber 14a of cylinder is connected with a damping force adjusting mechanism 34 furnished at the side of the cylinder 14 and is put in communication with the reserver chamber 18 via the mechanism 34. The mechanism 34 is formed in a single piece structure where a valve member 44 fitted with a sub-disc valve 47 and a rotary shutter 41 are installed in a valve case 37 and is fitted in a case 33 welded to the outer cylinder 16 fast by a snap ring 50. The rotary shutter 41 is operated by an actuator 51 so that the damping force is adjusted. Installation of the mechanism 34 is facilitated by sub-assembling the valve member 44 and shutter 41 to the valve case 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping force adjustable hydraulic shock absorber mounted on a suspension system of a vehicle such as an automobile.

[0002]

2. Description of the Related Art In a hydraulic shock absorber mounted on a suspension system of a vehicle such as an automobile, a damping force can be appropriately adjusted in order to improve ride comfort and steering stability in accordance with road surface conditions, running conditions and the like. There is a damping force adjustable hydraulic shock absorber.

An example of a conventional damping force adjusting hydraulic shock absorber will be described with reference to FIG.

As shown in FIG. 3, the damping force adjusting type hydraulic shock absorber 1 has a double cylinder structure in which an outer cylinder 3 is provided outside a cylinder 2 and a reservoir chamber 4 is formed between them. .
A piston 5 is slidably fitted in the cylinder 2 to form cylinder upper and lower chambers 2a and 2b, and a piston rod 6 is connected to the piston 5. A base valve 7 that defines a cylinder lower chamber 2b and a reservoir chamber 4 is provided at the bottom of the cylinder 2, and a damping force adjusting mechanism 8 is provided at the side of the cylinder 2. The cylinder 2 is filled with oil liquid, and the reservoir chamber 4 is filled with oil liquid and gas.

The cylinder upper and lower chambers 2a and 2b are connected by a communication passage 9 having a damping force generating mechanism (orifice, disk valve, etc.) provided in the piston 5. The lower cylinder chamber 2b and the reservoir are connected by a base valve 7 with an appropriate flow resistance. Further, the cylinder upper chamber 2a is connected to the damping force adjusting mechanism 8 by a conduit 10 inserted into the reservoir chamber 4, and communicates with the reservoir chamber 4 via the damping force adjusting mechanism 8.

The damping force adjusting mechanism 8 is provided with a dial 11 from the outside.
Is operated to rotate the shutter 12, the communication passage area (orifice area) between the cylinder upper chamber 2a and the reservoir chamber 4 can be adjusted.

With this configuration, the damping force adjusting mechanism controls the flow of the oil liquid in the communication passage 9 caused by the movement of the piston 5 accompanying the expansion and contraction of the piston rod 6 to generate the damping force, and the cylinder upper chamber 2a The damping force can be appropriately adjusted by changing the flow resistance of the oil liquid flowing through the pipe line 9 to the reservoir chamber 4 by the damping force adjusting valve 8.

Further, since the damping force adjusting mechanism 8 is provided on the side of the main body of the hydraulic shock absorber, there are few restrictions on the moving range of the piston 5 and the expansion and contraction stroke of the piston rod 6 can be lengthened.

In the damping force adjusting type hydraulic shock absorber in which the damping force adjusting mechanism is arranged on the side of the hydraulic shock absorber body as described above, the damping force adjusting valve is combined with the disc valve to adjust the damping force characteristic of the valve characteristic. What has been made possible is described in DE 35 53 287 A1.

[0010]

However, in the above conventional damping force adjusting hydraulic shock absorber, it is necessary to assemble the individual components of the damping force adjusting mechanism into the hydraulic shock absorber body,
Since the assembling process becomes complicated, there is a problem that the assembling workability is poor. In particular, in the case of the German Federal Republic of Patent that combines a damping valve with a damping force adjusting valve, the damping force adjusting valve and the disc valve are separately attached to the hydraulic shock absorber main body. When the number of parts of the hydraulic shock absorber is increased and the automatic assembly is attempted, the disk valve and the damping force adjusting valve must be installed in this order in the hydraulic shock absorber body. Deterioration of workability becomes a problem.

The present invention has been made in view of the above points, and a damping force adjusting mechanism including a damping force adjusting valve and a disc valve is arranged on a side portion of a hydraulic shock absorber body, and an assembling work is performed. An object of the present invention is to provide a damping force adjustable hydraulic shock absorber having excellent properties.

[0012]

In order to solve the above problems, the present invention provides a cylinder in which an oil liquid is sealed, a piston slidably fitted in the cylinder, and one end of which is the piston. A piston rod having the other end extended to the outside of the cylinder, an oil liquid passage that communicates with a chamber in the cylinder and allows oil to flow by sliding of the piston, and is provided on a side portion of the cylinder. And a damping force adjusting mechanism for adjusting the passage area of the oil liquid passage, wherein the damping force adjusting mechanism is a disk for controlling the flow of the oil liquid in the oil liquid passage. Valve and
A valve body for adjusting a passage area of the oil liquid passage is incorporated into a case to form an integral assembly, which is attached to a side portion of the cylinder.

[0013]

With this configuration, the damping force adjusting hydraulic shock absorber is assembled by mounting a case in which the disc valve and the valve body are incorporated into the inside and attached to the side portion of the cylinder.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

As shown in FIGS. 1 and 2, the damping force adjusting hydraulic shock absorber 13 has an inner cylinder 15 provided outside the cylinder 14 and an outer cylinder 16 provided outside the inner cylinder 15. It has a triple cylinder structure, and an annular passage 17 (oil liquid passage) is formed between the cylinder 14 and the inner cylinder 15, and a reservoir chamber 18 is formed between the inner cylinder 15 and the outer cylinder 16.

A piston 19 is slidably fitted in the cylinder 14, and the piston 19 allows the cylinder 14 to slide.
The inside is divided into two chambers, a cylinder upper chamber 14a and a cylinder lower chamber 14b. One end of a piston rod 20 is connected to the piston 19 by a nut 21.
The other end side of 20 is inserted into a rod guide 22 and a seal member 23 provided at the upper end of the cylinder 14 and extends to the outside of the cylinder 14.

At the lower end of the cylinder 14, a base valve 24
Is provided, and the cylinder lower chamber 14b and the reservoir chamber 18 are communicated with each other via the base valve 24. The cylinder 14 is filled with oil liquid, and the reservoir chamber 18 is filled with oil liquid and gas.

The piston 19 is provided with an extension-side communication passage 25 and a compression-side communication passage 26 which communicate the cylinder upper chamber 14a and the cylinder lower chamber 14b. At the end surface of the piston 19 on the cylinder lower chamber 14b side, a disc valve that allows only the flow of oil liquid from the cylinder upper chamber 14a side of the extension side communication passage 25 to the cylinder lower chamber 14b side to generate a damping force. 27 is provided, and a check valve 28 that allows only the flow of oil liquid from the cylinder lower chamber 14b side of the compression side communication passage 26 to the cylinder upper chamber 14a side is provided on the end surface on the cylinder upper chamber 14a side. ing.

The base valve 24 is provided with an expansion side passage 29 and a contraction side passage 30 which connect the cylinder lower chamber 14b and the reservoir chamber 18 to each other. Further, the check valve 31 that allows only the flow of oil liquid from the reservoir chamber 18 side of the extension side passage 29 to the cylinder lower chamber 14b side and the oil liquid from the cylinder upper chamber 14b side of the contraction side passage 30 to the reservoir chamber 18 side A disk valve 32 is provided which allows only the circulation of the above to generate a damping force.

A cylindrical accommodating member 33 whose inside communicates with the reservoir chamber 18 is welded to the side wall near the lower end of the outer cylinder 16, and a damping force adjusting mechanism 34 is fitted in the accommodating member 33. There is. Then, one end side of the annular passage 17 is provided with a cylinder upper chamber 14 through a hole 35 provided in a side wall near the upper end portion of the cylinder 14.
The other end of the cylinder is connected to the damping force adjusting mechanism 34 through a connection port 36 protruding from the side wall near the lower end of the inner cylinder 15, and the cylinder upper chamber 14a is connected to the annular passage 17 and the damping force. It is connected to the reservoir chamber 18 via the adjusting mechanism 34.

In the damping force adjusting mechanism 34, a guide portion 38 having a small diameter is formed on the bottom side in a bottomed cylindrical valve case 37 (case), and a guide port 39 is provided on the side wall of the guide portion 38. ing. The guide port 39 is provided in the reservoir chamber via a passage 40 formed between the valve case 37 and the containing member 33.
It is connected to 18. A cylindrical rotary shutter 41 as a valve body is fitted in the guide portion 38. Rotating shutter
A shutter port 42 is provided on the side wall of 41 so as to face the guide port 39, and the communication passage area between the guide port 39 and the shutter port 42 changes depending on the rotational position of the rotary shutter 41. The rotary shutter 41 has
The operation rod 43 is connected, and the operation rod 43 is rotatably inserted in the bottom portion of the valve case 37 and protrudes to the outside of the valve case 37.

A valve member 44 is fitted on the opening side of the valve case 37, and an inlet member 45 which is fitted on the connection port 36 to form a case is fitted on the valve member 44. The opening end of the valve case 37 is fixed by caulking the inside. The valve member 44 includes an inlet member 45 in the valve case 37.
An oil liquid passage 46 is provided that connects the side and the rotary shutter 41 side. At the end of the valve member 44 on the rotary shutter 41 side, a sub-disk valve 47 (disk that allows only the flow of oil liquid from the inlet member 45 side of the oil liquid passage 46 to the rotary shutter 41 side to generate a damping force) Valve) is attached by pin 48. The valve opening pressure of the sub disk valve 47 is set lower than the valve opening pressure of the disk valve 27 of the piston 19 and the disk valve 32 of the base valve 24.

In this way, the rotary shutter 41 and the valve member 44 to which the sub disk valve 47 is attached are assembled in the case consisting of the inlet member 45 and the valve case 37 to form an integrated assembly damping force adjusting mechanism 34. Is fitted in the housing member 33, and the inlet member 45 is fitted and brought into contact with the connection port 36 of the inner cylinder 15 to be positioned, and fixed by the snap ring 50 mounted in the inner circumferential groove 49 of the housing member 33. Has been done.

An actuator 51 is provided at the end of the housing member 33.
Are attached by bolts 52 and the actuator
The drive shaft 53 of 51 is connected to the operation rod 43 of the rotary shutter 41. The actuator 51 has a recess in the valve case 37.
The convex portion 55 that fits into the concave portion 54 is provided, and the concave portion 54 and the convex portion 55 have a substantially oval shape in which two surfaces a and b of the circular shape are removed, and the actuator 51 and the valve case 37 are provided. Positioning can be done in the direction of rotation with. In the figure, 56 is a dust cover, and 57 and 58 are mounting eyes.

The operation of this embodiment having the above-described structure will be described below.

During the extension stroke of the piston rod 20, as the piston 19 moves, the oil liquid in the cylinder upper chamber 14a becomes
Hole 35, annular passage 17, connection port 36, inlet member 45 of damping force adjusting mechanism 34, oil liquid passage 46 of valve member 44, shutter port 4
2, the reservoir chamber 18 through the guide port 39 and the passage 40
Flows to. As a result, a damping force is generated by the sub-disk valve 47, the rotary shutter 41 is rotated by the actuator 51, and the communication passage area between the guide port 39 and the shutter port 42 on the downstream side of the sub-disk valve 47 is changed. The damping force of the valve characteristic can be adjusted.

At this time, the oil liquid in the reservoir chamber 18 opens the check valve 31 of the base valve 24 and flows through the extension side passage 29 to the cylinder lower chamber 14b. Further, the gas in the reservoir chamber 18 expands as much as the piston rod 20 moves out of the cylinder 14. When the piston speed is high, the pressure in the cylinder upper chamber 14a rises, the disc valve 27 of the piston 19 opens, and the oil liquid in the cylinder upper chamber 14a opens in the expansion side communication passage.
Since it directly flows through the cylinder lower chamber 14b through 25, the damping force is also generated by the disc valve 27.

During the compression stroke of the piston rod 20, as the piston 19 moves, the oil liquid in the cylinder lower chamber 14b opens the check valve 28 of the piston 19 and flows through the compression side communication passage 26 to the cylinder upper chamber 14a. , Also, piston rod 20
The oil that has entered the cylinder 14 is
Damping force adjustment mechanism 34 from the cylinder upper chamber 14a through the annular passage
To flow into the reservoir chamber 18 to compress the gas in the reservoir chamber 18. As a result, a damping force is generated by the sub-disk valve 47, the rotary shutter 41 is rotated by the actuator 51, and the communication passage area between the guide port 39 and the shutter port 42 on the downstream side of the sub-disk valve 47 is changed. The damping force of the valve characteristic can be adjusted.

When the piston speed is high, the pressure in the cylinder lower chamber 14b rises, the disc valve 32 of the base valve 24 opens, and the oil liquid in the cylinder lower chamber 14b passes directly through the contraction side passage 30 to the reservoir. Since it flows to the chamber 18, the damping force is also generated by the disc valve 32.

In this way, on both the extension side and the contraction side, the movement of the piston 19 causes the oil liquid to flow through the damping force adjusting mechanism 34, and the damping force is generated by the sub disk valve 47, so that the rotary shutter 41 rotates. The damping force of the valve characteristic can be adjusted by changing the area of the communication path between the guide port 39 and the shutter port 42 on the downstream side of the sub disk valve 47 according to the position.

The damping force adjusting mechanism 34 is assembled as follows. The rotary shutter 41 is fitted to the valve case 37, the valve member 44 having the sub disk valve 47 attached and the inlet member 45 are fitted, and the opening of the valve case 37 is caulked to form an integrated assembly. . The damping force adjusting mechanism 34 sub-assembled in this way is fitted to the housing member 33 attached to the outer cylinder 16 on the hydraulic shock absorber body side, and the inlet member 45 is fitted to the connection port 36 of the inner cylinder 15. , Abut and position. Then, the snap ring 50 is attached to the inner circumferential groove 49 of the housing member 33 to fix the damping force adjusting mechanism 34.

In this way, the rotary shutter 34 (valve body)
Also, the damping force adjusting mechanism 34 in which the valve member 44 equipped with the sub disk valve 47 is integrally assembled in the valve case 37 can be easily assembled to the hydraulic shock absorber body.

[0033]

As described in detail above, in the damping force adjusting type hydraulic shock absorber of the present invention, the damping force adjusting mechanism is incorporated into the case with the disk valve and the valve body to form an integrated assembly.
Since it is mounted on the side of the cylinder, it can be easily assembled by incorporating the disc valve and valve body into the case and integrating them, and simply mounting the subassembly damping force adjustment mechanism on the side of the cylinder. The excellent effect of being advantageous even when performing automatic assembly is achieved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an embodiment of the present invention.

2 is a cross-sectional view of a damping force adjusting mechanism mounting portion of the apparatus of FIG.

FIG. 3 is a vertical cross-sectional view of a conventional damping force adjusting hydraulic shock absorber.

[Explanation of symbols]

 13 Damping force adjustable hydraulic shock absorber 14 Cylinder 19 Piston 20 Piston rod 17 Annular passage (oil liquid passage) 34 Damping force adjustment mechanism 37 Valve case (case) 47 Sub disk valve (disk valve) 41 Rotating shutter (valve body)

Claims (1)

[Claims] 1. A cylinder in which an oil liquid is sealed, a piston slidably fitted in the cylinder, a piston rod having one end connected to the piston and the other end extended to the outside of the cylinder. An oil liquid passage that communicates with a chamber in the cylinder to allow an oil liquid to flow by sliding of the piston; and a damping force adjusting mechanism that is provided at a side portion of the cylinder and adjusts a passage area of the oil liquid passage. In the damping force adjusting hydraulic shock absorber, the damping force adjusting mechanism includes a disc valve that controls the flow of the oil liquid in the oil liquid passage, and a valve body that adjusts the passage area of the oil liquid passage. A damping force adjusting hydraulic shock absorber, characterized in that it is incorporated into a case to form an integrated assembly and is attached to a side portion of the cylinder.