JPH0842621A - Shock absorber - Google Patents

Abstract

PURPOSE:To obtain a shock absorber which has high performance and durability, by interposing a spherical bearing between the inner periphery of a cylinder near the opening thereof and the outer periphery of a piston rod. CONSTITUTION:In a shock absorber 1, a spherical bearing 11, which is formed of an inner cylinder 14 having a spherical projecting surface in the periphery thereof and an outer cylinder 12 having a spherical recessed surface 13 in the inner periphery thereof, is interposed between the inner periphery of a cylinder 9 near the opening 10 and the outer periphery of a piston rod 2. When this shock absorber 1 receives a lateral load, curvature is generated in the piston rod 2. The spherical bearing 11 is oscillated in relation to this curvature of the piston rod 2, and a sliding part thereof is adjusted so as to always support the piston rod 2 in the parallel condition, and extension and contraction of the shock absorber 1 is smoothed. Even in the case where the shock absorber 1 receives a lateral load and curvature is generated in the piston rod 2, increase of a sliding load between the sliding part of the spherical bearing 11 and a sliding part of the piston rod 2 can be restricted.

Description

Detailed Description of the Invention

[0001]

The present invention is used in automobiles,
The present invention relates to a shock absorber that generates a damping force.

[0002]

2. Description of the Related Art A shock absorber used in an automobile or the like is mounted between a vehicle body and a wheel support to reduce vibration caused by unevenness of a road surface and hold an occupant and a load.
Further, there is an effect that the wheels are appropriately pressed against the ground to effectively apply the driving force and the braking force.

As such a shock absorber, there is a structure as shown in FIG. In the figure, 109 is an opening 110 at one end.
10 is a cylindrical cylinder having a cylinder 109, and a piston 10 that defines two oil chambers 121 and 122 on the inner circumference of the cylinder 109.
6 is fitted. This piston 106 has a cylinder 1
The reduced diameter portion 104 formed at one end of the piston rod 102 extending in the 09 axial direction engages with the reduced diameter portion 104.
The nut 108 was screwed into the threaded portion 105 formed at the tip of the piston rod 102, and the piston rod 102 was fixed to the piston 106. A lid 119 that closes the cylinder 109 is fixed to the opening 110 of the cylinder 109, and a seal member 116 made of an elastic material and an oil-containing resin are formed on the inner circumference between the inner circumference of the cylinder 109 near the opening 110 and the piston rod 102. A bearing 111 made of a sintered material and having a sliding member 118 was interposed.

The shock absorber 101 is provided with respect to the cylinder 109 in order to reduce vibrations caused by, for example, unevenness of the road surface.
02 moves in the axial direction. At this time, the sliding member 118
Has a configuration in which the piston rod 102 is slidably supported.

[0005]

The shock absorber 1 as described above.
If 01 is used for a long period of time, for example, when vibrations occur due to unevenness on a good road, the vibrations will not be collected well, and when a large vibration occurs on a bad road, continuous vibration (fluffy feeling)
Will increase. This is caused by a decrease in the damping force of the shock absorber 101, and one of the causes is wear of the sliding portion that supports the piston rod 102. This wear is caused by normal use of the shock absorber 101, but it is one of the causes.
One of them is the bending of the shock absorber 101 due to the lateral load applied to the shock absorber 101. The bending of the shock absorber 101 will be described with reference to FIG. 6. When a lateral load is applied to the shock absorber 101, a lateral load is applied to the piston rod 102, and when the lateral load is large, the piston rod 102 may be slightly bent. When the piston rod 102 slides in the vertical direction in such a state, the sliding load (friction) of the sliding portion, that is, the bearing 111 increases. The increase in the sliding load may reduce the function of the shock absorber 101, and the bearing 111 may be worn to reduce the damping force, resulting in a decrease in durability.

Therefore, an object of the present invention is to solve the above problems and to provide a shock absorber having high performance and durability.

[0007]

The constitution of the present invention is as follows.

A cylindrical cylinder having an opening at one end,
In a shock absorber that consists of a piston that fits inside the cylinder and a piston rod that has one end that engages with the piston and the other end that projects from the opening of the cylinder, the inner circumference near the opening of the cylinder and the outer circumference of the piston rod. And a spherical bearing consisting of an inner cylinder having a spherical convex surface on the outer circumference and an outer cylinder having a spherical concave surface on the inner circumference.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows a shock absorber 1 according to an embodiment of the present invention, and 9 is a cylindrical cylinder for containing an oil liquid. The cylinder 9 has an opening 10 at one end, and a piston 6 defining the inside of the cylinder 9 into two oil chambers 21 and 22 is fitted to the inner periphery of the opening 10. This piston 6 has two oil chambers 21 and 22.
A communication hole (not shown) that communicates with each other is formed. The piston 6 is engaged with a reduced diameter portion 4 formed at one end of a piston rod 2 extending in the cylinder 9 axial direction, and a nut 8 is attached to a screw portion 5 formed at the tip of the reduced diameter portion 4. Is screwed to fix the piston rod 2 to the piston 6. A lid 19 for closing the cylinder 9 is provided in the opening 10 of the cylinder 9.
Is fixed, and a seal member 1 made of an elastic material is formed on the inner circumference between the inner circumference near the opening 10 of the cylinder 9 and the piston rod 2.
A spherical bearing 11 made of a sintered material, which is provided with 6 and a sliding member 18 made of an oil-containing resin, is interposed. The seal member 16 is
The oil liquid in the cylinder 9 causes the piston rod 2 and the sliding member 18 to move.
It is possible to suppress the outflow to the outside of the cylinder 9 from between. Further, the spherical bearing 11 is an inner cylinder 1 having a spherical convex surface 15 on the outer circumference.
4 and a spherical concave surface 1 having the same curvature as the spherical convex surface 15 on the inner circumference
3 and an outer cylinder 12 having a spherical concave surface 1 of the outer cylinder 12.
3 comprises a circumferential groove 20 in which an annular seal ring 17 is arranged. The seal ring 17 is arranged in the circumferential groove 20 and suppresses the oil liquid in the cylinder 9 from flowing out of the cylinder 9 from between the inner cylinder 14 and the outer cylinder 12.

Next, a method of manufacturing the shock absorber 1 will be described.

First, the seal ring 17 is arranged in the circumferential groove 20 of the outer cylinder 12 shown in FIG. 3 and the inner cylinder 1 shown in FIG.
The seal member 16 and the sliding member 18 are arranged at predetermined positions on the inner circumference of the No. 4. Then, the inner cylinder 14 is inserted into the outer cylinder 12 having the insertion opening 7 having substantially the same shape as the front projection shape of the inner cylinder 14. After the insertion, the inner cylinder 14 is rotated 90 degrees, and the sliding member 1
8 is positioned in the axial direction of the outer cylinder 12, and the assembly of the spherical bearing 11 is completed. After that, as shown in FIG. 1, after inserting the lid 19 and the spherical bearing 11 from the side of the reduced diameter portion 4 of the piston rod 2, the piston 6 is engaged with the reduced diameter portion 4, and the nut 8 is screwed into the screw portion 5. The piston 6 is fixed to the piston rod 2. And finally, after fitting the piston 6 to the inner circumference of the cylinder 9 and injecting the oil liquid into the cylinder 9, the opening 1 of the cylinder 9
The spherical bearing 11 is engaged with the inner periphery near 0 and the lid 19 is fixed to the opening 10 of the cylinder 9, and the manufacture of the shock absorber 1 is completed.

Next, the operating state of the shock absorber 1 will be described.

The shock absorber 1 operates by repeatedly performing an extension process in which the piston rod 2 moves out of the cylinder 9 and a contraction process in which the piston rod 2 moves into the cylinder 9. First, when the extension process is performed, the piston 6 moves upward with respect to the cylinder 9 and the oil liquid flows from the upper oil chamber 21 to the lower oil chamber 22 through a communication hole (not shown) formed in the piston 6. To do. On the contrary, when the reduction process is performed, the piston 6 moves downward with respect to the cylinder 9, and the oil liquid passes through the communication hole (not shown) of the piston 6 and the lower oil chamber 22.
To the upper oil chamber 21.

The operating state when the shock absorber 1 receives a load from the lateral direction with respect to the axis will be described with reference to FIG.

When the shock absorber 1 receives a lateral load, the piston rod 2 is bent. The spherical bearing 11 oscillates with respect to the bending of the piston rod 2 and is adjusted so that the sliding portion can always be supported in parallel with the piston rod 2, so that the shock absorber 1 can be smoothly expanded and contracted. .

Accordingly, even if the shock absorber 1 receives a lateral load and the piston rod 2 bends, the spherical bearing 11 swings, and the sliding portion can be supported in parallel with the piston rod 2 at all times. It is possible to suppress an increase in sliding load (friction) between the rod 2 and the sliding portion.

In the above embodiment, the spherical bearing 11 was assembled by inserting the inner cylinder 14 into the outer cylinder 12 and rotating it by 90 degrees. However, the spherical bearing 11 is assembled only by this method. Not something.

In the above embodiment, the case where the piston rod 2 is bent has been described, but the same effect can be obtained when the cylinder 9 is bent.

Further, although the sliding member 18 is interposed between the piston rod 2 and the spherical bearing 11 in the above embodiment, the sliding member 18 may be omitted.

[0021]

As described above, according to the present invention, a cylindrical cylinder having an opening at one end, a piston fitted to the inner circumference of the cylinder, and one end portion engaging with the piston and the other end portion In a shock absorber consisting of a piston rod protruding from the opening of the cylinder, an inner cylinder having a spherical convex surface on the outer circumference and an outer cylinder having a spherical concave surface on the inner circumference between the inner circumference near the opening of the cylinder and the outer circumference of the piston rod. Even if the shock absorber receives a lateral load and the piston rod or cylinder bends, the spherical bearing oscillates and the sliding part is always supported in parallel with the piston rod. Therefore, it is possible to suppress an increase in sliding load (friction) between the piston rod and the sliding portion, and to obtain high performance. Further, when the sliding load between the piston rod and the sliding portion is suppressed, wear of the sliding portion is also suppressed and the durability of the shock absorber can be improved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional front view showing a shock absorber according to an embodiment of the present invention.

FIG. 2 shows an inner cylinder according to an embodiment of the present invention, (C) is a sectional front view and (B) is a plan view.

FIG. 3 shows an outer cylinder according to an embodiment of the present invention, (C) is a sectional front view, and (B) is a bottom view.

FIG. 4 is a sectional front view showing a state in which the shock absorber according to the embodiment of the present invention receives a lateral load.

FIG. 5 is a partial cross-sectional front view showing a conventional shock absorber.

FIG. 6 is a sectional front view showing a state in which a conventional shock absorber receives a lateral load.

[Explanation of symbols]

 2 Piston rod 6 Piston 9 Cylinder 10 Opening 11 Spherical bearing 12 Outer cylinder 13 Spherical concave surface 14 Inner cylinder 15 Spherical convex surface

Claims (1)

[Claims] 1. A cylindrical cylinder (9) having an opening (10) at one end, a piston (6) fitted to the inner circumference of the cylinder (9), and one end of the piston (6). In a shock absorber comprising a piston rod (2) which is engaged and the other end of which protrudes from an opening (10) of a cylinder (9), the inner periphery of the cylinder (9) near the opening (10) and the piston rod (2). A spherical bearing (11) consisting of an inner cylinder (14) having a spherical convex surface (15) on the outer circumference and an outer cylinder (12) having a spherical concave surface (13) on the inner circumference is interposed between the outer circumference and the outer circumference. Characteristic shock absorber.