JPH04114143U - Oil lock mechanism of hydraulic shock absorber - Google Patents

Abstract

(57) [Summary] [Purpose] To apply an oil lock with a simple configuration and shorten the basic length of a hydraulic shock absorber. [Structure] A valve member 22 that reduces the flow area of the oil passage 19 that communicates the reservoir chamber 18 and the lower cylinder chamber at the end of the compression stroke.
A shaft portion 23 is provided that is intrudably locked into a hollow portion 21 formed at the lower end of the piston rod 3, and a flange-shaped shielding portion 26 is formed at the lower end of the shaft portion 23 to shield the oil passage 19. An orifice 27 for generating a damping force is formed in this flange-shaped shielding part 26.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to an oil lock mechanism that prevents a hydraulic shock absorber from bottoming out.

0002

[Conventional technology]

As shown in FIG. 5, a conventional hydraulic shock absorber has a cylinder 1 inside an outer tube 101. 02 is set upright, the piston rod 103 is inserted into the cylinder 102, and the piston rod 103 is inserted into the cylinder 102. A piston 104 that slides on the inner peripheral surface of the cylinder 102 is fixed to the lower end of the connecting rod 103. The piston 104 is equipped with oil passages 105 and 106 for generating damping force. Valves 107 and 108 are installed to open and close oil passages 105 and 106, respectively.

0003 A bottom valve mechanism is attached to the bottom of the tube 101 (lower part of the cylinder 102). 110 is provided, and a bottomed cylinder facing into the cylinder 102 is provided on the bottom valve mechanism 110. A shaped collar 111 is provided, and this collar 111 has a cylinder lower chamber and a reservoir chamber 112. An orifice 113 is formed that communicates with the bottom valve mechanism 110 through the bottom valve mechanism 110. On the other hand, an extension part 103a extending from the lower end of the piston rod 103 has a collar 111 inside. A piece 115 that can be fitted around the circumference is attached, and a check valve is installed inside this piece 115. An oil hole 117 is formed in the piece 115.

0004 In this hydraulic shock absorber, at the end of the compression stroke of the piston rod 103, the piece 1 The piece 115 and the collar 111 are connected by fitting the piece 15 into the collar 111. Hydraulic oil is sealed in between and an oil lock is applied. And at the beginning of the extension stroke Hydraulic oil flows from the oil hole 117 of the piece 115 to the collar 1 via the check valve 116. 11.

[0005]

[Problem that the idea aims to solve]

However, in the oil lock mechanism of the conventional hydraulic shock absorber mentioned above, the pin It is necessary to allow a certain amount of mating length between the base and collar, which increases the basic length. Furthermore, P Because the base and collar slide against each other, galling, scratches, and noise may occur, resulting in poor durability. This will reduce reliability, and if the axes of the piece and collar become misaligned, operability will deteriorate. .

[0006]

[Means to solve the problem]

In order to solve the above problems, the present invention has developed an oil tank that communicates between the reservoir chamber and the lower cylinder chamber. The valve member that narrows the flow area of the passageway at the end of the compression stroke has a hollow part formed at the lower end of the piston rod. A shaft part is provided that can be inserted into the cavity, and an oil passage is provided at the lower end of this shaft part. A flange-like shielding part is formed, and this flange-like shielding part has a damping force generating part. An oil hole was formed.

[0007]

[Effect]

At the end of the compression stroke, the flange-shaped shielding part of the valve member blocks the oil passage, leaving only the orifice. It forms a flow path and locks the oil, eliminating the metal-to-metal fit and creating an oil lock. At this time, the shaft part of the valve member enters the piston rod. Therefore, the basic length becomes shorter.

[0008]

【Example】

Embodiments of the present invention will be described below with reference to the accompanying drawings. Figure 1 shows the application of this invention. Figure 2 is a sectional view of the main parts of a hydraulic shock absorber equipped with an oil lock mechanism. FIG. 3 is a cross-sectional view of the main part of another embodiment of the present invention, and FIG. 4 is a cross-sectional view of the main part of the lock state. It is a sectional view of the principal part of yet another example of a plan.

[0009] A cylinder 2 is installed upright inside the bottomed cylindrical tube 1. The piston rod 3 is inserted through the piston rod 3, and the lower end of the piston rod 3 is inserted into the cylinder 2. A piston 4 that slides on the circumferential surface is fixed, and this piston 4 is provided with an oil passage 5 for generating damping force. , 6, and a plurality of disc valves that open and close these oil passages 5. A valve 8 consisting of a plurality of disc valves that opens and closes a valve 7 and an oil passage 6 is installed. Ru.

0010 A bottom valve mechanism 10 is installed at the bottom of the tube 1 (lower part of the cylinder 2). The bottom valve mechanism 10 has oil passages 12 and 13 formed in the bottom piece 11. A valve 14 opens and closes these oil passages 12 and a valve 1 opens and closes oil passages 13. I am wearing 5. Moreover, on the bottom piece 11 of this bottom valve mechanism 10, A bottom cap 17 is provided, and this bottom cap 17 has a cylinder lower chamber and a reservoir. An oil passage 19 communicating with the chamber 18 is formed.

[0011] On the other hand, a hollow part 21 is formed in the lower end of the piston rod 3 in the axial direction. A valve member 22 for blocking the oil passage 19 is suspended from the portion 21 . This valve member 22 is It has a shaft part 23 that can enter into the hollow part 21, and the upper end of this shaft part 23 has a The attached locking ring 24 can be attached to the stopper ring 25 attached to the lower part of the hollow part 21. This prevents the valve member 22 from falling off from the hollow portion 21. In addition, the valve member 22 A flange-shaped shielding part 26 that can shield the oil passage 19 is formed at the lower end of the shaft part 23. An orifice 27 is formed in this shielding part 26, and an orifice 27 is formed in the lower surface outer peripheral edge of the shielding part 26. A rubber ring 28 is attached. Furthermore, the flange-like shielding portion 26 of the valve member 22 and A spring 29 that biases the valve member 22 downward is interposed between the lower surface of the piston 4 and the lower surface of the piston 4. ing.

0012 The operation of the hydraulic shock absorber configured as above will be explained. piston during compression stroke When the piston rod 3 descends from the state shown in FIG. Hydraulic oil flows from the cylinder lower chamber through oil passage 19 and oil passage 12 of bottom valve mechanism 10. It flows into the reservoir chamber 18. At this time, the valve member 22 moves as the piston rod 3 descends. At the end of the compression stroke of the piston rod 3, as shown in FIG. The rubber ring 28 of the flange-like shielding portion 26 of the member 22 contacts the bottom cap 17 The oil passage 19 is blocked and the oil is locked, and the hydraulic oil in the lower cylinder chamber is released from the valve part. The material 22 flows into the reservoir chamber 18 through the orifice 27, and the orifice The damping force is generated by the system 27.

[0013] When the piston rod 3 further descends, the shaft portion 23 of the valve member 22 Since the piston rod 3 enters the hollow part 21 of the rod 3, the piston rod 3 is attached to the spring 2. Descend against the forces. In this way, a part of the valve member 22 advances into the piston rod 3. The basic length does not become long.

[0014] Then, from this state, the piston rod 3 rises in the rebound direction and at the same time Hydraulic oil is replenished from inside the bottom cap 17 to the cylinder lower chamber, and further the reservoir chamber 1 Hydraulic oil is replenished from 8 and the piston rod 3 rises.

[0015] Next, in another embodiment shown in FIG. 3, on the bottom piece 11 of the bottom valve mechanism 10, A collar 31 is disposed on the upper end surface of the collar 31 to provide a flange-shaped shield for the valve member 22. The rubber ring 28 of the portion 26 is brought into contact with the rubber ring 28 of the portion 26. In addition, a further example shown in Figure 4 In the embodiment, a collar portion extending downward from the outer edge of the flange-like shielding portion 26 of the valve member 22 is used. 26a is integrally formed, and a rubber ring 28 is attached to the lower end surface of this collar portion 26a. At the end of the compression stroke, the rubber ring 28 touches the bottom piece 11 of the bottom valve mechanism 10. It is made to touch the top surface. Even if these methods are used, the same effect as in the above embodiment can be obtained. is obtained.

[0016]

[Effect of the idea]

As explained above, according to the present invention, the reservoir chamber and the lower cylinder chamber are communicated with each other. The valve member that reduces the flow area of the oil passage at the end of the compression stroke is formed at the lower end of the piston rod. A shaft part is provided that can enter into the hollow part, and the lower end of this shaft part is filled with oil. A flange-like shielding part is formed to shield the road, and a damping force is generated in this flange-like shielding part. Since oil holes are formed for normal use, oil locks can be applied with a simple configuration, and metal There are no problems with mating between metal parts, the basic length can be shortened, and durability and reliability are improved. Ru.

[Brief explanation of drawings]

[Figure 1] Cross-sectional view of essential parts of a hydraulic shock absorber equipped with an oil lock mechanism to which the present invention is applied

[Figure 2] Cross-sectional view of the main parts of the hydraulic shock absorber in the oil-locked state

[Fig. 3] Cross-sectional view of main parts of another embodiment of the present invention

[Fig. 4] Cross-sectional view of main parts of yet another embodiment of the present invention

[Figure 5] Cross-sectional view of main parts of a conventional hydraulic shock absorber

[Explanation of symbols]

1...Tube, 2...Cylinder, 3...Piston rod, 4
...Piston, 10...Bottom valve mechanism, 11...Bottom piece, 17...Bottom cap, 19...Oil passage, 21...Hollow part, 22...Valve member, 23...Shaft part, 24...Latching ring, 25...Stopper ring, 26 ...flange-shaped shielding part, 2
7... Orifice, 28... Rubber ring, 29... Spring, 31... Collar.

Claims (1)

[Scope of utility model registration request] 1. A hydraulic shock absorber comprising a valve member that throttles the flow area of an oil passage communicating between a reservoir chamber and a lower cylinder chamber at the end of a compression stroke, wherein the valve member has a groove extending in the axial direction of the lower end of the piston rod. A shaft portion that enters the formed hollow portion is provided, a locking portion for pulling up the shaft portion when it is extended is provided in the hollow portion, and a flange-like shielding portion is formed at the lower end of the shaft portion to shield the oil passage. An oil lock mechanism for a hydraulic shock absorber, characterized in that an oil hole for generating a damping force is formed in the flange-shaped shielding part.