KR101901446B1 - Piston valve of shock absorber - Google Patents

Abstract

A piston valve of a shock absorber of the present invention is disclosed. According to an aspect of the present invention, there is provided an internal combustion engine comprising: a piston body coupled to a piston rod, the piston body having a compression passage and a tension passage formed therein in the longitudinal direction; an intake valve, an upper retainer, And a piston multi-disc, a lower retainer, and a lower washer sequentially disposed at a lower portion of the piston body, wherein the bimetal is provided between the piston body and the piston multi- a bi-metal disk may be provided.

Description

[0001] The present invention relates to a piston valve of a shock absorber,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piston valve of a shock absorber, and more particularly, to a piston valve of a shock absorber capable of providing an adequate ride comfort even when the viscosity of working oil in a cold cylinder is increased.

Generally, a shock absorber is a main component of a suspension system, which supports the weight of the vehicle body and suppresses and attenuates the vibration transmitted from the road surface to the vehicle body. Such a shock absorber absorbs vibration energy in the up and down direction of the wheel (wheel) caused by a road surface irregularity and alleviates it, thereby preventing the vibration from being directly transmitted to the vehicle body. The shock absorber contributes to improving the ride comfort of the driver and passengers, protecting the cargo, and protecting each part of the vehicle.

Such a shock absorber includes a cylinder and a piston rod slidably received in the cylinder, the cylinder being connected to the wheel side through a suspension arm or the like, the piston rod being connected to the vehicle body side, and a piston valve being connected to the lower end of the piston rod . Accordingly, when the vehicle travels on an irregular road surface, the shock absorber continuously and elastically moves and suppresses vibrations transmitted from the road surface to the vehicle body. That is, as the working oil in the cylinder flows through the piston valve, the kinetic energy is converted into thermal energy, so that the vibration generated in the vehicle is attenuated.

However, such a conventional shock absorber as described above is prepared on the basis of those used at room temperature, and the viscosity of the working oil in the cylinder is increased in a cold place in a low temperature environment such as Russia and China and the orifice formed in the piston valve The resistance increases and excessive damping force is generated. In order to solve this problem, a premium oil whose viscosity does not greatly change from room temperature even at a low temperature is applied, but the cost of use of the premium oil is greatly increased.

The piston valve of the shock absorber according to the embodiment of the present invention allows a constant load to be applied to the piston multiple disc provided in the direction in which the working oil flows in the expansion and contraction of the shock absorber when the viscosity of the working oil increases according to the low temperature environment, It is possible to reduce the pre-load (pre-load) of the disk so that the working oil can flow easily, thereby suppressing the excessive increase of the damping force.

According to an aspect of the present invention, there is provided an internal combustion engine comprising: a piston body coupled to a piston rod, the piston body having a compression passage and a tension passage formed therein in the longitudinal direction; an intake valve, an upper retainer, And a piston multi-disc, a lower retainer, and a lower washer sequentially disposed at a lower portion of the piston body, wherein the bimetal is provided between the piston body and the piston multi- a bi-metal disk may be provided.

Also, the bimetal disc may be deformed toward the piston multi-disc when the temperature is cryogenic below 0 ° C, and the load may be applied to the multi-disc.

In addition, the bimetal disc is extended to the piston body when the temperature is normal, and the load applied to the piston multiple disc can be released.

The piston valve of the shock absorber according to an embodiment of the present invention is provided with a bimetal disc which is deformed according to a change in temperature, and the bimetal disc applies a constant load to the piston multiple disc in a low temperature environment, So that the working oil can flow easily even if the viscosity of the working oil increases. Accordingly, there is an effect that the ride feeling can be improved by suppressing an excessive increase of the damping force due to the viscosity increase of the working oil.

In addition, at normal temperature, the bimetal disc is opened, the load applied to the piston multi-disc is removed, and the preload applied to the multiple discs is restored to the set value to provide appropriate damping force. Thus, there is an effect that a feeling of ride can be secured by maintaining the feeling of ride.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described in detail with reference to the following drawings, which illustrate preferred embodiments of the present invention, and thus the technical idea of the present invention should not be construed as being limited thereto.
1 is an exploded perspective view showing a piston valve structure of a shock absorber according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a piston valve of a shock absorber according to an embodiment of the present invention.
FIG. 3 is a view showing a state in which a bimetal disc provided in a piston valve of a shock absorber according to an embodiment of the present invention applies a load to a piston multiple disc.
4 is a view showing an operating state of a piston valve during a compression stroke of a shock absorber according to an embodiment of the present invention.
5 is a view showing an operating state of a piston valve during a tension stroke of a shock absorber according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to fully convey the spirit of the present invention to a person having ordinary skill in the art to which the present invention belongs. The present invention is not limited to the embodiments shown herein but may be embodied in other forms. For the sake of clarity, the drawings are not drawn to scale, and the size of the elements may be slightly exaggerated to facilitate understanding.

FIG. 1 is an exploded perspective view showing a piston valve structure of a shock absorber according to an embodiment of the present invention, FIG. 2 is a sectional view showing a piston valve of the shock absorber, and FIG. 3 is a cross- Fig. 8 is a view showing a state in which the disc applies a load to the piston multiple disc.

1 to 3, a piston valve 100 of a shock absorber according to an aspect of the present invention is coupled to a lower end of a piston rod 10 disposed along a central axis in a cylinder (not shown). Thus, the inside of the cylinder is divided into a tension chamber A on the upper side and a compression chamber B on the lower side with respect to the piston valve 100. The piston valve 100 has an intake part 120 on the uppermost side and a piston body 110, a bimetal disk 130 and a piston multi disk part 140 are sequentially arranged and assembled to the lower side of the intake part 120.

The intake part 120 is disposed on the upper side of the piston body 110 and includes an upper washer 121, an intake spring 123, an upper retainer 125, and an intake valve 127 that are sequentially arranged from the upper side to the lower side Respectively. The upper washer 121 and the intake valve 127 are formed with through holes 121a and 127a so that working oil can flow, respectively. The through hole 121a of the upper washer 121 and the through hole 127a of the intake valve 127 allow the piston rod 10 to flow to the tensile flow passage 112 formed in the piston body 110 It plays the role of the euro. On the other hand, the intake spring 123 is provided to provide an elastic force to the intake valve 127. The intake spring 123 and the intake valve 127 serve to allow the flow of working oil through the compression passage 114 formed in the piston body 110 when the piston rod 10 is bent during the compression stroke, This operation structure will be described below again.

The piston body 110 has a tensile flow passage 112 and a compression passage 114 formed in the longitudinal direction so that the working oil can flow. The tensile flow path 112 and the compression path 114 are each formed of a plurality of pieces. The tensile flow passage 112 is formed along the radial direction at a position close to the center of the piston body 110. The compression oil passage 114 is formed along the radial direction with respect to the center of the piston body 110 at a position spaced apart from the tension oil passage 112 by a distance from the center of the piston body 110.

The piston multi disk unit 140 is disposed below the piston body 110 and includes a piston multiple disk 143, a lower retainer 142 and a lower washer 141 sequentially arranged from the upper side to the lower side. At this time, the piston multi-disc 143 is formed to have a size corresponding to the position where the tension channel 112 is formed. Accordingly, during the compression stroke of the piston rod 10, the piston multiple discs 143 are provided to block the flow passage 114 to block the flow of working oil.

The uppermost intake part 120 receives the intake spring 123, the upper retainer 125, and the intake valve 127 from the upper washer 121 downwardly, as shown in FIG. The bimetal disc 130 is disposed at the lower end of the piston body 110 and the piston body 110 is disposed at the lower end of the piston body 110. In this case, The piston multi disk unit 143, the lower retainer 142, and the lower washer 141 are sequentially arranged downward in the piston multi disk unit 140. A nut 20 is fixedly connected to the lowermost end of the piston rod 10 so that the intake part 120, the piston body 110, the bimetal disk 130, and the piston multi disk part 140 are separated from the piston rod 10 It is not separated. At this time, as the piston valve 100 is assembled to the piston rod 10 by the nut 20, the piston multi-disc 143 is brought into close contact with the piston body 110 side to pre-load the piston multi- : Preceding load) occurs.

The bimetal disc 130 is interposed between the lower end of the piston body 110 and the piston multi-disc 143. The bimetal disc 130 has a property of being deformed according to the temperature condition. For example, the bimetal disc 130 is deformed to face the piston multi-disc 143 when it is at a cryogenic temperature below 0 ° C. The bimetal disc 143 is deformed in the direction of the arrow P in FIG. 3 and applies a load to the piston multiple disc 143. The load applied to the piston multi disc 143 by the deformation of the bimetal disc 143 The preload is reduced. That is, the preload of the piston multiple disk 143 varies depending on the temperature condition.

On the other hand, when the bimetal disc 143 is at normal temperature, it spreads toward the piston body 110 and releases the load applied to the piston multiple disc 143. That is, the bimetal disc 143 does not operate at room temperature and does not affect the damping force through the working oil.

The operation of the piston valve 100 according to the expansion and contraction of the piston rod 10 of the shock absorber having the above structure will now be described.

First, at the time of the compression stroke, the fluid filled in the cylinder, that is, the working oil is pressurized, and the internal pressure of the compression chamber B located below the piston valve 100 increases. Accordingly, the working oil has a motive force to escape to the outside through the piston valve 100, and a part of the working oil passes through the compression oil passage 114 of the piston valve 100 while pushing the intake valve 127, (A) located on the upper side of the casing (100). At this time, the working fluid overcomes the elastic force of the intake spring 123 that provides the elastic force to the intake valve 127 when the intake valve 127 is pressed, and elastically deforms the intake spring 123 together.

Since the working oil is a viscous substance, it generates a physical force that can be escaped by pushing the intake valve 127 and the intake spring 123, and this physical force is transmitted to the intake valve 127 for blocking the movement of the working oil, And the intake spring 123, the damping force is generated.

Next, while the internal pressure of the compression chamber B is reduced during the tensioning stroke, the working oil from the outside of the tension chamber A and the cylinder has mobility to flow into the compression chamber B through the piston valve 100. The working oil in the tension chamber A is then introduced into the compression chamber B while passing through the tension channel 112 of the piston valve 100 and pushing the bimetal disc 130 and the piston multiple discs 143. More specifically, the working oil flows through the through hole 121a of the upper washer 121 and the through hole 127a of the intake valve 127 to the tensile flow passage 112. At this time, as in the compression stroke, the physical force of the working oil causes the bimetal disk 130 and the piston multiple disk 143 to cancel each other with the elastic reaction force to block the movement of the working oil, and a damping force is generated.

The compression and tension strokes of the shock absorber described above describe the operation state at room temperature, and the viscosity of the working oil is increased in a harsh environment where the temperature environment is low, so that the damping force also changes. That is, as the viscosity of the working oil increases, the resistance increases when the piston rod 10 is passed through the tensile flow path 112 during the tensile stroke of the piston rod 10, resulting in an excessive damping force, and the ride feeling is lowered. Accordingly, the piston valve 100 according to one aspect of the present invention is configured such that the bimetal disc 130 is deformed to face the piston multiple disc 143 in a low-temperature environment when the viscosity of the working oil increases according to the low temperature environment do. This deformation causes a load to be applied to the piston multi-disc 143, which reduces the preload of the piston multi-disc 143. That is, as the preload of the piston multi-disc 143 is reduced, the piston multi-disc 143 is easily tilted even with a small pressure, so that the flow of the operating oil is smooth. As a result, the damping force due to the viscosity increase of the working oil is prevented from being excessively increased, which leads to a decrease in the damping force.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

10: Piston rod 100: Piston valve
112: Tensioning flow path 114: Compressing flow path
121: upper washer 123: intake spring
125: upper retainer 127: intake valve
130: Bimetal disc 141: Lower washer
142: Lower retainer 143: Piston multiple disc

Claims (3)

An intake valve, an upper retainer, an intake spring, an upper washer, and an upper washer, which are sequentially disposed on an upper portion of the piston body, A lower retainer, and a lower washer,
A bi-metal disk provided between the piston body and the piston multiple disk and being deformed according to a temperature condition,
Wherein the bimetal disc is deformed toward the piston multi-disc when the temperature is at a very low temperature of 0 ° C or less, and is applied to apply a load to the multi-disc. delete The method according to claim 1,
Wherein the bimetallic disc extends toward the piston body when the bimetal disc is at normal temperature and releases the load applied to the piston multiple disc.

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