JPS6078127A - hydraulic shock absorber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The object of the present invention is to prevent the generation of fluid noise caused by the operation of the piston of a hydraulic shock absorber.

It is well known that a hydraulic shock absorber is equipped with a plurality of piston boats that allow and control the flow of oil to the piston. At that time, the rapid flow of oil caused a cavitation phenomenon between the piston and the surrounding wall of the boat, resulting in undesirable fluid noise.

The present invention is designed to prevent the generation of fluid noise as described above.

For this reason, in the present invention, a vortex generating plate is provided protrudingly in contact with the inlet of the piston boat 1, and the vortex generating plate generates a vortex in the oil flowing past, and this vortex is introduced into the oil boat, so that the oil This is designed to suppress the occurrence of cavitation inside the boat, thereby preventing the generation of fluid noise that is likely to occur during the operation of the piston of the hydraulic shock absorber.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 1 is a longitudinal cross-sectional side view of a piston portion showing an embodiment of a hydraulic shock absorber based on the present invention, FIG. 2 is an exploded perspective view showing the same piston and a vortex generating plate, and FIG. FIG. 4 is an enlarged longitudinal cross-sectional side view of the main part showing the state in which cavitation is suppressed in the piston boat by the vortex flow, and FIG. 4 is a plan view of the same part.

In the drawing, 1 is a piston and 2 is a shilling.

3 is a piston rod, 4 is a plurality of piston ports bored in the piston 1, and is equipped with a check valve 5 that is opened only when the shock absorber is extended.

Reference numeral 6 designates a plurality of piston ports similarly drilled in the piston 1, which are equipped with a check valve 7 that is opened only when the shock absorber is compressed, and the check valve 7 is provided with a through hole 7a.

These mechanisms are almost the same as those of conventional products, but in the present invention, as is clear from FIG.
．． The vortex generating plate 8 is arranged facing the inlet 4a of the vortex generator 4.

The vortex generating plate 8 is composed of a central base plate 8a, a number of supporting parts 8b corresponding to the piston ports 4, and a tip part 8C which is provided by bending the tip of the supporting part 8b so as to cross the front surface of the inlet 4a. The substrate 8a is provided with a through hole 8d through which the piston rod is inserted.

Furthermore, the tip portion 8C is not simply bent from the support portion 8b, but is bent so that the tip portion 8C faces diagonally to the piston port 4, and if necessary, it can be adjusted to a desired pitch like a propeller. It may be formed to have.

When oil flows into the piston port 4 at high speed as indicated by the arrow in FIG. This allows each piston boat 4
The shape of the vortex generating plate 8 is not necessarily limited to that of the embodiment.

Note that 9 is a recess provided for assembling the vortex generating plate 8 of the piston 1 to the piston.

In the shock absorber of the present invention having the above-described structure, when the shock absorber is extended, the oil flows through the through hole 7a + piston port 4 as shown by arrow S in the first diagram, and the check valve 5 is forcibly opened to increase the flow rate at high speed. However, since the tip 8C of the vortex generating plate 8 is provided diagonally across this flow, the opposing surface A of the tip 8C facing the flow S as shown in FIG. is under high pressure, while the opposite surface B is under low pressure. At the same time, the tip 8 is oblique to the flow S. Therefore, when the flow S flows through the tip 8c, the pressure is lowered on the opposite surface B. As shown in the fourth figure, a spiral is formed around the axis of the piston port 4.

At this time, the free end of the tip 8C extends to approximately the center of the piston port 4, and it is possible to create a more effective vortex by giving the tip 8C a propeller-like pitch. Needless to say.

As a result, the vortex generated by the tip 8C is forced into the piston boat 4 at high speed, and as a result, the cavitation that would normally occur between the port 4 and the surrounding wall is suppressed by the vortex, This is to appropriately suppress the fluid noise caused by cavitation as described in .

As described above, according to the present invention, by providing the tip 8C of the vortex generating plate 8 so as to face the inlet 4a of the piston port 4, a vortex is actively introduced into the port 4,
This suppresses the cavitation that tends to occur upstream of the port 4 and suppresses the generation of fluid noise, and has an excellent feature of preventing unpleasant fluid noise with an extremely simple structure.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional side view of a piston part showing one embodiment of a hydraulic shock absorber based on the present invention, Fig. 2 is an exploded perspective view showing the piston and a vortex generating plate, and Fig. 6 is a vortex generating plate according to the present invention. FIG. 4 is an enlarged longitudinal cross-sectional side view of the main part showing the cavitation suppressed state in the piston port by the vortex flow, and a plan view of the same part. 1 - Piston 2 - Cylinder 3 - Piston rod 4 - Piston port 48 - Inlet 5 - Check pulp 6 - Piston port 7 - Check pulp 7a - Through hole 8 - Vortex generating plate 88 - Substrate 8b - Support part 80 - Tip part 8 d - Through hole 9 - Concave part Fig. 1 Fig. 2 Fig. 3 Fig. 4 Diagram C

Claims (1)

[Claims] A vortex generation plate that generates a vortex is attached to the inlet of a piston boat that allows and controls the flow of oil when the piston moves, and the vortex generated by the generation plate suppresses cavitation in the piston boat and suppresses fluid noise. A hydraulic shock absorber featuring: