KR100757811B1 - Shock absorber - Google Patents

Abstract

The shock absorber of the present invention includes a cylinder in which a working fluid is received, one end of which is inserted into one side of the cylinder, and the other end of which is installed inside the cylinder to partition the cylinder. Since it includes a valve for controlling the flow and an auxiliary valve for controlling the flow of the working fluid, it is effective to increase the ride comfort by maintaining a low damping force by adjusting the flow rate of the working fluid.

Suspension, shock absorber, piston valve, rebound chamber, compression chamber

Description

 Shock Absorber

1 is a view showing a shock absorber according to the present invention,

Figure 2 is a perspective view showing a piston of the shock absorber according to the present invention,

3 is a view showing a part of the compression stroke of the shock absorber according to the present invention;

4 is a view showing a part of the rebound stroke of the shock absorber according to the present invention;

5 is a graph showing the damping performance of the shock absorber according to the present invention.

<Brief Description of Major Codes in Drawings>

100: shock absorber 110: cylinder

120: piston rod 130: piston valve

131: piston 133: compression flow path

135: Rebound Euro 137: Compression Disc

139: rebound disk 150: auxiliary valve

151: auxiliary flow path 153: elastic member

155: ball member 157: housing

159: through

The present invention relates to a shock absorber, and more particularly, to a shock absorber, which is made of a cylinder made of a monotube type, and has an increased attenuation performance in a compression stroke or a rebound stroke.

In general, a suspension system of a vehicle is a device that connects the vehicle body to the wheel and absorbs the shock transmitted from the road surface to the wheel while driving to prevent the vibration from being transmitted directly to the vehicle body. Therefore, the shock absorber is a research and development and development of various types of suspensions, with the main purpose of ensuring the stability of handling, protecting the cargo and protecting each part of the vehicle, utilizing the good handling characteristics, and maximizing the comfortable riding comfort of the driver. It is being applied.

Suspension device of such a vehicle is composed of a shock absorbing spring, a shock absorber for adjusting the operation of the spring. The shock absorber includes a cylinder and a piston rod and a piston slidably received in the cylinder, wherein the cylinder is connected to the wheel side through a suspension arm or the like, and the piston is connected to the vehicle body side by the piston rod.

Accordingly, the shock absorber may perform a function of suppressing and attenuating vibration transmitted from the road surface to the vehicle body while being continuously compressed or rebounded when the vehicle travels on an irregular road surface.

At this time, the piston partitions the inside of the cylinder into a compression chamber and a rebound chamber. Furthermore, the compression chamber may be partitioned from the storage chamber for volume compensation of the compression chamber by a base valve device or the like installed under the vehicle body. Between these chambers are provided flow paths for selectively allowing the flow of the working fluid (or working oil) and valves for controlling the flow paths in accordance with the expansion and contraction of the shock absorber.

The valve allows the fluid to move in one direction by the pressing force of the disk, but the disk is opened or closed with respect to the flow path by the pressure difference between the chambers according to the expansion or contraction of the shock absorber.

Such a conventional valve delays the opening of the disk to the flow of the working fluid in a high speed vehicle, so that when a shock is applied to the vehicle body, a rebound stroke is performed to damp the impact of the vehicle body. However, if the disc is delayed opening, the rebound attenuation performance of the shock absorber is degraded in a vehicle traveling at high speed, which causes a decrease in ride comfort.

The present invention has been made to solve the problems described above, an object of the present invention is to provide a shock absorber that prevents the attenuation performance is reduced by smoothly flowing the working fluid even when the vehicle is traveling at a high speed. will be.

The present invention for achieving the above object is a cylinder in which a working fluid is accommodated, one end is inserted into one side of the cylinder, the other end is a piston rod drawn out of the cylinder, and installed in the cylinder And partitions the cylinder and provides a shock absorber including a valve for controlling the flow of the working fluid and an auxiliary valve for controlling the flow of the working fluid.

The auxiliary valve is preferably installed on the piston rod.

The auxiliary valve is formed in the piston rod and is connected to the upper flow path and the lower side of the cylinder partitioned by the valve, an elastic member inserted on the auxiliary flow path, and inserted into the side of the auxiliary flow path It is preferable to include a housing having a through hole communicated with the auxiliary flow path and a ball member for communicating or closing the through hole of the auxiliary flow path and the housing by the elastic member.

The through hole of the housing is preferably formed smaller than the outer diameter of the ball member.

The surface of the housing in contact with the ball member is preferably formed to be tapered.

Hereinafter, an embodiment of a suspension device according to the present invention will be described in detail with reference to the drawings.

1 is a view showing a shock absorber according to the present invention, Figure 2 is a perspective view showing a piston of the shock absorber according to the present invention.

Figure 3 is a view showing a part of the compression stroke of the shock absorber according to the present invention, Figure 4 is a view showing a part of the rebound stroke of the shock absorber according to the present invention, Figure 5 is a damping performance of the shock absorber according to the present invention. Is a graph.

As shown in these figures, a mono tube type shock absorber 100 having an upper side connected to a vehicle body and a lower side connected to a wheel is inserted into a cylinder 110, one end of which is inserted into the cylinder 110, and the other end of the A piston rod 120 drawn out of the cylinder 110, a piston valve 130 reciprocating up and down within the cylinder 110, an oil chamber OC and a gas chamber located inside the cylinder 110. It comprises a free piston 140 for separating the (GC), and the auxiliary valve 150 provided on the piston rod (120).

The piston valve 130 is installed at one end of the piston rod 120 introduced into the cylinder 110 to partition the inside of the cylinder 110 into the compression chamber CC and the rebound chamber RC. In this case, the portion in which the piston valve 130 is installed may be any one of the oil chamber OC and the gas chamber GC partitioned by the free piston 140. In the figure, as an embodiment of the shock absorber according to the present invention, the piston valve 130 is installed at the oil chamber OC side.

The piston valve 130 includes a piston 131 having a plurality of flow paths 133 and 135 through which a working fluid is moved, and a disk which is stacked on the upper and lower surfaces of the piston 131 to open or close the flow paths 133 and 135 of the piston 131. (137,139).

The piston 131 has a through hole 131a through which the piston rod 120 is inserted in a central portion thereof, and flow paths 133 and 135 communicating with the upper and lower sides of the piston 131 are formed around the through hole 131a. . In addition, the flow paths 133 and 135 are divided into a compression flow path 133 and a rebound flow path 135. The disks 137 and 139 are installed to contact the upper and lower surfaces of the piston 131, respectively. The disks 137 and 139 open the lower side of the compression flow path 133 during the compression stroke and contact the bottom surface of the piston 131, and open the rebound flow path 135 during the rebound stroke and the piston 131. Compression disk 137 is installed in contact with the upper surface of the. Since a plurality of leaf springs are stacked on the compression disk 137 and the rebound disk 139, a plurality of open flow paths (not shown) are formed. At this time, as shown in FIG. 2, the compression guide member 133a surrounding the compression flow path 133 protrudes from the upper surface of the piston 131, and the rebound flow path 135 is disposed on the lower surface of the piston 131. The surrounding rebound guide member 135a is installed to protrude.

The auxiliary valve 150 is installed in the piston rod 120, is formed inside the piston rod 120, and has an auxiliary flow path 151 for communicating the compression chamber CC and the rebound chamber RC with the auxiliary flow path 151. The ball member 155, which will be described later, is installed on the elastic member 153 for pressing the auxiliary flow passage 151 to be closed, and is inserted into the side of the auxiliary flow passage 151 to communicate with the auxiliary flow passage 151 ( It comprises a housing 157 having a 159, and a ball member 155 for communicating or closing the auxiliary passage 151 and the through hole 159 of the housing 157 by the elastic member 153.

Here, the through hole 159 of the housing 157 is formed to have an outer diameter smaller than the outer diameter of the ball member 155 so that the ball member 155 does not escape through the through hole 159. In addition, the surface of the housing 157 in contact with the ball member 155 is formed to be tapered to ensure contact between the ball member 155 and the housing 157 and to prevent the ball member 155 from flowing.

Hereinafter, the operation of the shock absorber having the above configuration will be described in detail.

First, as shown in FIG. 3, during the compression stroke, the piston rod 120 descends to compress the compression chamber CC, and the piston valve 130 installed to be inserted into the piston rod 120 also descends.

At this time, when the piston 131 is lowered during the compression stroke, the piston valve 130 pressurizes the rebound disk 139 when the working fluid in the compression chamber CC presses the rebound disk 139 and the rebound guide member 135a. Rebound flow path 135 is closed because it is in contact. Therefore, the working fluid is introduced into the compression flow path 133 opened under the piston 131 to pressurize the compression disk 137. The compression disk 137 is then bent by the pressure of the working fluid to move the working fluid to the rebound chamber (RC).

In addition, the auxiliary valve 150 pressurizes the ball member 155 by the working fluid drawn into the auxiliary passage 151 from the compression chamber CC. At this time, the elastic member 153 also presses the ball member 155 to prevent the through hole 159 and the auxiliary flow path 151 of the housing 157 from communicating.

As shown in FIG. 4, the piston rod 120 is extended during the rebound stroke so that the piston valve 130 is raised to move toward the rebound chamber RC. At this time, the piston valve 130, when the piston 131 is raised, the working fluid in the rebound chamber RC presses the compression disk 137, the compression guide formed on the lower surface of the compression disk 137 and the piston 131 Since the member 133a is in contact, the compression flow path 133 is closed. Therefore, the working fluid is introduced into the rebound flow path 135 opened at the upper side of the piston 131 to pressurize the rebound disk 139. Then, the rebound disk 139 is bent by the pressure of the working fluid to move the working fluid to the compression chamber (CC).

Here, in the auxiliary valve 150, the working fluid introduced into the auxiliary flow path 151 along with the extension of the piston rod 120 moves toward the compression chamber CC. In addition, the pressure inside the auxiliary passage 151 is lowered. Accordingly, the working fluid presses the ball member 155 through the through hole 159 of the housing 157, and the ball member 155 moves to the elastic member 153 to open the through hole 159 and the auxiliary flow path 151. Communication causes the working fluid to be transferred to the compression chamber CC.

5 is a damping performance (A) when the shock absorber 100 according to the present invention when only the piston valve 130 is operated during the rebound stroke, and when the piston valve 130 and the auxiliary valve 150 is operated together It is a graph showing the damping performance (B).

The shock absorber 100 requires a high damping performance A so that a damping force is increased in proportion to the operating speed of the piston rod 120 when the traveling vehicle is impacted.

In addition, if a continuous shock is applied to the vehicle when the vehicle is traveling at a high speed, the damping force is kept constant even though the speed of the piston rod 120 is increased, thereby increasing the amount of movement of the working fluid through the auxiliary valve 150 and thus lowering the damping force. Maintain performance (B).

At this time, the damping force between the damping performance (A) and the damping performance (B) is adjustable in accordance with the elastic modulus (K) of the elastic member 153 to adjust the opening degree of the auxiliary valve 150.

Therefore, the auxiliary valve 150 can be easily moved to the compression chamber (CC) in a short time through the piston valve 130 and the auxiliary valve 150 to attenuate when the impact is applied to the vehicle body, high speed It is possible to improve ride comfort by maintaining low damping force at.

According to this, the shock absorber of the present invention has the effect of increasing the ride comfort by maintaining a low damping force by adjusting the flow rate of the working fluid through the auxiliary valve when the vehicle is traveling at a high speed.

Claims (5)

A cylinder in which a working fluid is received; A piston rod having one end inserted into one side of the cylinder and the other end drawn out of the cylinder; A piston valve installed inside the cylinder to partition the cylinder and to control the flow of the working fluid; And An auxiliary valve for controlling the flow of the working fluid, The auxiliary valve may include an auxiliary flow path formed in the piston rod and configured to communicate an upper side and a lower side of the cylinder partitioned by the piston valve; An elastic member inserted on the auxiliary channel; A housing having a through hole inserted into a side of the auxiliary channel and in communication with the auxiliary channel; And And a ball member configured to communicate or close the through hole of the housing and the auxiliary flow path by the elastic member. delete delete The method according to claim 1, Shock absorber, characterized in that the through-hole of the housing is formed smaller than the outer diameter of the ball member. The method according to claim 4, Shock absorber, characterized in that the surface of the housing in contact with the ball member is formed to be tapered.

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