JPS5831688Y2 - Hydraulic shock absorber for vehicles - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hydraulic shock absorber used as a suspension system for a vehicle.

More specifically, it consists of a dual inner and outer cylindrical body, a piston is slidably fitted into the inner cylinder, the piston rod is supported on the vehicle body side, and the cylindrical body is supported on the wheel side via knuckles, etc. In this hydraulic shock absorber for vehicles, the inner cylinder, including the piston and piston rod, is eccentrically outward (towards the wheel) with respect to the axis of the outer cylinder, in order to reduce the side force (lateral force) in the strut type suspension system. The present invention relates to a hydraulic shock absorber for a vehicle that smoothes and improves the operability of the shock absorber and improves riding comfort.

A strut type suspension system such as a MacPherson strut type 1 is used as a suspension system for a vehicle.

Figure 4 shows an outline of the conventional rat suspension system.
The hydraulic shock absorber 1 includes an outer cylinder 2, an inner cylinder 3, a piston 4 slidably fitted in the inner cylinder 3, and a piston rod 5. The piston rod 5 has its upper end attached to the vehicle body 6 side, and the lower end of the cylinder body. is supported by a wheel 8 via a knuckle 7, and 9 in the figure is a lower arm.

A spring 12 is interposed between a spring receiver 10 provided at the upper part of the outer cylinder 2 and a spring receiver 11 at the upper end of the rod 5.

In the above, the inner cylinder 3 is provided concentrically with respect to the outer cylinder 4, and includes the piston 4, the piston rod 5, and the spring 1.
2 is similarly provided, and a span a exists between the first axis of the shock absorber and the ground contact center line of the wheel 8.

Therefore, the reaction force against the load W of the wheel 8 acts on the shock absorber 1 as a moment obtained by multiplying the load by the span, and this causes a side force (lateral force) on the rod 5 of the shock absorber 1.
acts as a bending force.

Therefore, the frictional resistance between the piston and the cylindrical body increases, impeding the smooth movement of the piston, and making it difficult to ensure smooth buffering operation.
Moreover, the shock absorber will not be able to fully demonstrate its original function.

Furthermore, due to the side force, it is necessary to increase the bending rigidity of the shock absorber, rod, etc., resulting in an increase in cost and weight.

Therefore, it is desirable to reduce the span a, but a certain amount of clearance b between the wheel 8 and the shock absorber 1 is required due to the attachment of snow chains, etc., and it is practically difficult to bring the shock absorber 1 close to the wheel. It is.

Furthermore, it is practically impossible to match the axis of the shock absorber 1 with the center line of the wheel 8.

The present inventors devised the present invention in order to solve the above-mentioned problems of hydraulic shock absorbers in strut type suspension systems.

The purpose of this invention is to make the inner cylinder, piston, and piston rod eccentric to the outside (wheel side) with respect to the axis of the outer cylinder, thereby reducing the span between the shock absorber's operating center line and the wheel center line. While ensuring the clearance between the shock absorber and the wheels, set it as small as possible to reduce the side force on the shock absorber and rod as much as possible, reduce friction on the piston, smooth operation, and improve the shock absorber's original characteristics. To provide a hydraulic shock absorber for a vehicle that is designed to fully demonstrate its functions and improve the riding comfort of the vehicle.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic longitudinal cross-sectional view of a hydraulic shock absorber according to the present invention, in which a shock absorber 20 has an outer cylinder 21. A cylinder body 23 consisting of an inner cylinder 22,
It includes a piston 24 slidably fitted into an inner cylinder 22 and a piston rod 25 extending upward.

The upper end of the piston rod 25 is connected to the vehicle body 26, and the lower end of the cylindrical body 23 is connected to a wheel 28 via a knuckle 27. The knuckle 27 is connected to the vehicle body by a lower arm 29.

In the above, the axis of the inner cylinder 22 housed inside the outer cylinder 21 is eccentric to the outside, ie, toward the wheel 28, with respect to the axis N--N of the outer cylinder 21.

In the illustration, the outer diameter portion of the inner cylinder 22 on the wheel side is brought into contact with the inner diameter portion of the outer cylinder 21 on the wheel side.

Therefore, while maintaining the clearance b between the wheel 28 and the outer cylinder 21, the span a1 between the center line of the wheel 28 and the axis of the inner cylinder 22, the piston 24 fitted therein, and the rod 25, that is, the operating center line, is It is obtained by subtracting the eccentricity e from the conventional span a.

In this way, the inner cylinder 22, the piston 24, and the rod 25 are made eccentric to the outside (towards the wheel), and the spring 32 interposed between the spring receiver 30 at the upper part of the outer cylinder 21 and the spring receiver 31 at the upper end of the rod 25 is The shaft center is also eccentric and installed concentrically with the above-mentioned operating axis.

Although not shown, the hydraulic pressure generating chamber 33 on the lower side of the piston 24 and the reservoir chamber 34 provided outside the inner cylinder 22 communicate with each other via a check valve or the like, and the reservoir chamber 34 has a crescent-shaped cross section as shown in FIG. It will be done.

The reservoir chamber 34 is biased to one side and has a large cross section, so the damping force variable communication pipe 35 is installed in this part.
Furthermore, it is possible to insert objects with a large effective diameter.

As described above, the ground contact center line of the wheel 28 and the shock absorber 2
The span a1 with respect to the zero operating axis is reduced by the amount of eccentricity e compared to the conventional case, so the moment acting on the shock absorber and rod is reduced, that is, the side force is reduced and the frictional resistance of the piston is also reduced.

In this way, the smooth operation of the shock absorber can be achieved, allowing the shock absorber to fully perform its original function and improving riding comfort.

FIG. 3 shows a modified embodiment of the invention, in which the spring 132
The spring receivers 130, 13 are arranged with an inclined offset so that the lower part is on the outside and the upper part is on the inside.
1 is tilted in a parallel state.

By doing so, the shock absorber 20 is pressed in a direction that compensates for the bending force due to the side force, reducing the side force, and a high friction reduction effect can be obtained by the synergistic effect with the above.

In addition, the same parts in the figures are given the same reference numerals.As is clear from the above, according to the present invention, the inner cylinder, piston,
By making the piston rod eccentric to the outside (wheel) side with respect to the outer cylinder, the side force on the shock absorber can be reduced as much as possible, smoothing the operation and fully demonstrating the shock absorber's original function. It is possible to ensure the comfort of the vehicle and improve the riding comfort of the vehicle.

In addition, the above effect can be further improved by using an inclined offset spring, and the above effect can be achieved by eccentricity of the inner cylinder, etc., the structure is simple, and a reservoir chamber with a thick cross section can be obtained by eccentricity, and the damping force can be improved. It has significant practical effects, such as being able to install variable delivery pipes while ensuring a sufficient effective diameter.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; Fig. 1 is an explanatory longitudinal cross-sectional view of the device according to the present invention, Fig. 2 is a cross-sectional view of the main part of the shock absorber, and Fig. 3 is a diagram of a modified embodiment. , FIG. 4 is a diagram illustrating a conventional example. In the drawing, 20 is a shock absorber, 21 is an outer cylinder, 22 is an inner cylinder, 2
3 is a cylinder, 24 is a piston, 25 is a rod, 26 is a vehicle body, 27 is a knuckle, and 28 is a wheel.

Claims (1)

[Scope of utility model registration request] Hydraulic pressure for vehicles consists of a dual inner and outer cylindrical body, with a piston slidably fitted into the inner cylinder, with the piston rod supported on the vehicle body side and the cylindrical body supported on the wheel side via knuckles, etc. A hydraulic shock absorber for a vehicle, characterized in that the inner cylinder includes a piston and a piston rod, and its axis is eccentrically outward (toward the wheel) with respect to the axis of the outer cylinder.