JP2010002004A - Check valve structure of hydraulic shock absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a check valve structure of a hydraulic shock absorber, preventing a bridge of a lower valve constituting a check valve from blocking up an oil hole (a round hole) of an upper valve. <P>SOLUTION: In this check valve 20 structure of the hydraulic shock absorber 10, a lower valve 21 and an upper valve 22 are stacked in order and the inner peripheral ends thereof are fixed on a seat surface to which an inner peripheral port 15A and an outer periphery port 15B of a piston 15 are opened. The lower valve 21 includes: a cutout 21C, which is disposed at a part of the outer peripheral end and to which the outer periphery port 15B is communicated; and a plurality of fan-shaped holes 21A, which are disposed in the circumferential direction on the inner periphery side and to which the inner peripheral port 15A is communicated. The upper valve 22 includes a plurality of round holes 22A disposed at equal spaces in the circumferential direction on the inner periphery side and communicated with the fan-shaped holes 21A of the lower valve 21. In this structure, a plurality of bridges 21B provided between the adjacent fan-shaped holes 21A of the lower valve 21 are disposed at unequal spaces in the circumferential direction of the lower valve 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a check valve structure for a hydraulic shock absorber.

  As a check valve structure of the hydraulic shock absorber, a lower valve and an upper valve are laminated in order on the seat surface where the inner peripheral port and outer peripheral port of the piston open, and their inner peripheral ends are fixed. It is provided with a notch that is arranged at a part of the end and communicates with the outer peripheral side port, and is provided with a plurality of fan-shaped holes that are arranged in the circumferential direction on the inner peripheral side and communicate with the inner peripheral side port. Are provided with a plurality of oil holes (round holes) arranged at equal intervals in the circumferential direction so as to be able to communicate with the fan-shaped holes of the lower valve.

  In the extension stroke where the piston is pulled out from the cylinder, in the low speed region of the piston speed, the oil in the piston rod side oil chamber passes from the notch at the outer peripheral end of the lower valve constituting the check valve to the piston side. The oil flows into the oil chamber and generates an extension side damping force due to the restriction resistance of the notch.

  Next, in the above-described extension side stroke, in the middle and high speed range of the piston speed, the oil in the piston rod side oil chamber is separated from the oil hole (round hole) of the upper valve constituting the check valve and the fan-shaped hole of the lower valve. The extension side damping valve is pushed open through the inner peripheral side port, and the extension side damping force due to the bending resistance of the extension side damping valve is generated.

Further, in the pressure side stroke in which the piston is pushed into the cylinder, the oil in the piston side oil chamber passes through the outer peripheral port of the piston and opens the lower valve and the upper valve of the check valve to flow into the piston rod side oil chamber. Functions as a suction valve.
Reality 3-48431

  However, in the prior art, a plurality of bridges provided between adjacent fan-shaped holes of the lower valve constituting the check valve are arranged at equal intervals in the circumferential direction of the lower valve. Therefore, when assembling the check valve together with the piston on the piston rod, it is difficult to specify the assembly position relationship between the lower valve and the upper valve in the circumferential direction. May be blocked. As a result, the flow rate of oil flowing from the piston rod side oil chamber to the piston side oil chamber through the check valve is markedly insufficient when the piston speed in the extension stroke becomes a medium to high speed range exceeding 0.6 m / sec, for example. The damping force may be excessive. Variations in damping force characteristics occur between hydraulic shock absorber assemblies.

  An object of the present invention is to prevent the bridge of the lower valve constituting the check valve from blocking the oil hole of the upper valve as much as possible in the check valve structure of the hydraulic shock absorber.

  According to the first aspect of the present invention, the lower valve and the upper valve are sequentially stacked on the seat surface where the inner peripheral port and the outer peripheral port of the piston open, and the inner peripheral ends thereof are fixed. It is provided with a notch that is arranged in part and communicates with the outer peripheral side port, and is provided with a plurality of fan-shaped holes that are arranged in the circumferential direction on the inner peripheral side and communicate with the inner peripheral side port. In a check valve structure of a hydraulic shock absorber having a plurality of oil holes arranged at equal intervals in a direction and capable of communicating with a fan-shaped hole of a lower valve, between adjacent fan-shaped holes of a lower valve A plurality of provided bridges are arranged at unequal intervals in the circumferential direction of the lower valve.

  According to a second aspect of the invention, in the first aspect of the invention, the upper valve further comprises six or more oil holes.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the lower valve further includes three fan holes and three bridges.

  According to a fourth aspect of the present invention, in the first or second aspect of the present invention, the lower valve further comprises two fan-shaped holes and two bridges.

(Claim 1)
(a) A plurality of bridges provided between adjacent fan-shaped holes of the lower valve were arranged at unequal intervals in the circumferential direction of the lower valve. Therefore, when assembling the check valve together with the piston on the piston rod, the lower valve bridge has at most one oil hole in the upper valve, even if no special attention is paid to the circumferential assembly position relationship between the lower valve and the upper valve. Just plug it. As a result, the flow rate of oil flowing from the piston rod side oil chamber to the piston side oil chamber through the check valve is substantially stable when the piston speed is in the middle to high speed range exceeding 0.6 m / sec, for example, in the extension side stroke. To ensure a substantially constant damping force. Variations in damping force characteristics among hydraulic shock absorber assemblies can be kept small.

(Claim 2)
(b) Under the design conditions where the outer diameter of the piston is limited, the hole diameter of the oil hole provided in the upper valve cannot be increased. In a check valve in which the number of oil holes in the upper valve is 5 or less, the flow rate of oil passing through the check valve is always insufficient in the extension stroke, and a desired damping force characteristic cannot be obtained. Therefore, the upper valve is provided with six or more oil holes.

(Claim 3)
(c) In the check valve in which the lower valve has three bridges arranged at equal intervals, when the upper valve has all six holes or all nine oil holes, all three bridges block the oil holes. (3 oil holes may be blocked), and when the upper valve is provided with all 8 oil holes, 2 of the 3 bridges block the oil holes (about 1.5 Oil holes may be blocked).

  On the other hand, in the check valve in which the three bridges provided in the lower valve are arranged at unequal intervals, when the upper valve has all six holes, all eight holes, and all nine oil holes, three bridges are provided. Only one of the bridges plugs the oil hole. Even if one oil hole of the upper valve is closed, the other oil hole is not closed.

  (d) In the check valve assembly stage, when the lower valve and the upper valve are mixed and handled, the circumferential length of the three fan holes of the lower valve is (the lower valve has two fan holes). The outer peripheral edge of the upper bulb enters the fan-like hole of the lower bulb and avoids biting into a deep area on the back side of the inner peripheral edge. It prevents entanglement between the parts of the lower valve and the upper valve and improves the handling of these parts.

(Claim 4)
(e) In the check valve in which the lower valve has two bridges arranged at equal intervals, when the upper valve has all six holes or all eight oil holes, all of the two bridges block the oil holes. (Two oil holes may be blocked).

  On the other hand, in the check valve in which the lower valve has two bridges arranged at unequal intervals, when the upper valve has all six holes or all eight oil holes, one of the two bridges. Only this bridge plugs the oil hole. Even if one oil hole of the upper valve is closed, the other oil hole is not closed.

  1 is a cross-sectional view showing a check valve structure of a hydraulic shock absorber, FIG. 2 is a plan view showing a lower valve, FIG. 3 is a plan view showing an upper valve, and FIG. 4 shows a first example of a check valve. ) Is a schematic view showing an example of the present invention, (B) is a schematic view showing a conventional example, FIG. 5 is a plan view showing different assemblies of the check valve of the first example, and FIG. 6 is a second example of the check valve. , (A) is a schematic diagram showing an example of the present invention, (B) is a schematic diagram showing a conventional example, FIG. 7 shows a third example of a check valve, (A) is a schematic diagram showing an example of the present invention, (B ) Is a schematic diagram showing a conventional example.

  As shown in FIG. 1, the hydraulic shock absorber 10 has a piston rod 12 inserted into a hydraulic oil storage chamber of a cylinder 11, and a valve stopper 13, a washer 14, a check valve 20, a piston 15, an extension side at the insertion end of the piston rod 12. The damping valve 30, the washer 16 and the valve stopper 17 are inserted and fastened with a nut 18. The extension side damping valve 30 is composed of a laminate of a plurality of plate valves.

  The piston 15 is in fluid-tight sliding contact with the hydraulic oil storage chamber of the cylinder 11, and the hydraulic oil storage chamber of the cylinder 11 is divided into a piston rod side oil chamber 11A in which the piston rod 12 is accommodated and a piston side in which the piston rod 12 is not accommodated. The oil chamber 11B is partitioned. The piston 15 includes an inner peripheral side port 15A and an outer peripheral side port 15B that allow the piston rod side oil chamber 11A and the piston side oil chamber 11B to communicate with each other, and the inner peripheral side port 15A and the outer peripheral side port 15B open. The check valve 20 is disposed on the seat surface on the oil chamber 11A side, and the expansion-side damping valve 30 is disposed on the seat surface on the piston-side oil chamber 11B side where the inner peripheral port 15A opens.

  The check valve 20 is configured by laminating a lower valve 21 and an upper valve 22 in order on the above-described seat surface of the piston 15 and fixing the inner peripheral ends thereof around the piston rod 12 as described above.

  As shown in FIG. 2, the lower valve 21 is a disc-shaped plate valve, and is provided with a plurality of fan-shaped holes 21A that are arranged in the circumferential direction on the inner circumferential side and communicate with the inner circumferential port 15A. A bridge 21B is provided between the fan-shaped holes 21A and 21A. The lower valve 21 includes a notch 21C that is disposed at a part of the outer peripheral end (a plurality of locations in this embodiment) and communicates with the outer peripheral port 15B.

  As shown in FIG. 3, the upper valve 22 is a disk-shaped plate valve, and is arranged at equal intervals in the circumferential direction on the inner peripheral side so as to be able to communicate with the fan-shaped hole 21 </ b> A of the lower valve 21. A hole (round hole) 22A is provided.

  However, the hydraulic shock absorber 10 has the following configuration so that the bridge 21B of the lower valve 21 constituting the check valve 20 does not block the round hole 22A of the upper valve 22 as much as possible. . That is, a plurality of bridges 21 </ b> B provided between adjacent fan-shaped holes 21 </ b> A and 21 </ b> A of the lower valve 21 are arranged at unequal intervals in the circumferential direction of the lower valve 21. Hereinafter, a specific example of the check valve 20 will be described.

First example (FIGS. 2 to 5)
FIG. 4A shows the check valve 20 of the first example. The lower valve 21 is provided with three fan holes 21A, three bridges 21B, and the three bridges 21B are arranged at intervals of 134 degrees, 94 degrees, and 132 degrees in the circumferential direction. The upper valve 22 is provided with nine round holes 22A, and these round holes 22A are arranged at equal intervals in the circumferential direction.

  When the check valve 20 is assembled, even if the assembly positions in the circumferential direction of the lower valve 21 and the upper valve 22 are shifted as shown in FIGS. 5A to 5C, for example, the three bridges of the lower valve 21 are used. Only one bridge 21 </ b> B of 21 </ b> B only closes the round hole 22 </ b> A of the upper valve 22. 5A shows an assembled state in which the lower valve 21 and the upper valve 22 are in the reference position, and FIG. 5B shows an assembled state in which the lower valve 21 is shifted by an angle a with respect to the upper valve 22 in the reference position. FIG. 5C shows an assembled state in which the lower valve 21 is displaced by an angle b with respect to the upper valve 22 at the reference position.

  FIG. 4B is a comparative example with respect to the first example, and is different from the first example in that the three bridges 21B of the lower valve 21 are arranged at equal intervals. In this comparative example, all of the three bridges 21B of the lower valve 21 close the round holes 22A of the upper valve 22, and three of the nine holes 22A of the upper valve 22 are closed.

Second example (Fig. 6)
FIG. 6A shows the check valve 20 of the second example. The lower valve 21 is provided with three fan holes 21A, three bridges 21B, and the three bridges 21B are arranged at intervals of 115 degrees, 127 degrees, and 118 degrees in the circumferential direction. The upper valve 22 was provided with a total of eight round holes 22A, and these round holes 22A were arranged at equal intervals in the circumferential direction.

  Even when the assembly positions of the lower valve 21 and the upper valve 22 in the circumferential direction are shifted when the check valve 20 is assembled, only one bridge 21B of the three bridges 21B of the lower valve 21 is It only closes the round hole 22A.

  FIG. 6B is a comparative example with respect to the second example, and differs from the second example in that the three bridges 21B of the lower valve 21 are arranged at equal intervals. In this comparative example, one of the three bridges 21B of the lower valve 21 closes one round hole 22A of the upper valve 22, and the other bridge 21B About one half of the round holes 22A is closed, and about 1.5 of the eight holes of the upper valve 22 are closed.

Third example (Fig. 7)
FIG. 7A shows a check valve 20 of the third example. The lower bulb 21 is provided with three fan holes 21A, three bridges 21B, and the three bridges 21B are arranged at intervals of 134 degrees, 91 degrees, and 135 degrees in the circumferential direction. The upper valve 22 was provided with six round holes 22A, and these round holes 22A were arranged at equal intervals in the circumferential direction.

  Even when the assembly positions of the lower valve 21 and the upper valve 22 in the circumferential direction are shifted when the check valve 20 is assembled, only one bridge 21B of the three bridges 21B of the lower valve 21 is It only closes the round hole 22A.

  FIG. 7B is a comparative example with respect to the third example, and is different from the third example in that the three bridges 21B of the lower valve 21 are arranged at equal intervals. In this comparative example, all three bridges 21B of the lower valve 21 close the round holes 22A of the upper valve 22, and three of the six holes 22A of the upper valve 22 are closed.

  Further, in the check valve 20, even when the lower valve 21 includes two fan-shaped holes 21A and includes two bridges 21B, the upper valve 22 includes six or eight round holes 22A. At this time, all of the two bridges 21B of the lower valve 21 block the round holes 22A of the upper valve 22, block two of the six holes 22A of the upper valve 22, or all of the upper valve 22 Of the eight holes, two round holes 22A may be blocked. Accordingly, even in such a check valve 20, two bridges 21 </ b> B of the lower valve 21 are arranged at unequal intervals in the circumferential direction of the lower valve 21. Only the bridge 21 </ b> B may only block the round hole 22 </ b> A of the upper valve 22.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in the present invention.

FIG. 1 is a cross-sectional view showing a check valve structure of a hydraulic shock absorber. FIG. 2 is a plan view showing the lower valve. FIG. 3 is a plan view showing the upper valve. 4A and 4B show a first example of a check valve, wherein FIG. 4A is a schematic diagram showing an example of the present invention, and FIG. 4B is a schematic diagram showing a conventional example. FIG. 5 is a plan view showing different assemblies of the check valve of the first example. 6A and 6B show a second example of the check valve, wherein FIG. 6A is a schematic diagram showing an example of the present invention, and FIG. 6B is a schematic diagram showing a conventional example. FIG. 7 shows a third example of the check valve, (A) is a schematic diagram showing an example of the present invention, and (B) is a schematic diagram showing a conventional example.

Explanation of symbols

10 Hydraulic shock absorber 11 Cylinder 12 Piston rod 15 Piston 15A Inner peripheral side port 15B Outer peripheral side port 20 Check valve 21 Lower valve 21A Fan-shaped hole 21B Bridge 21C Notch 22 Upper valve 22A Round hole (oil hole)

Claims (4)

A lower valve and an upper valve are laminated in order on the seat surface where the inner peripheral port and outer peripheral port of the piston open, and the inner peripheral ends thereof are fixed.
The lower valve is arranged at a part of the outer peripheral end and has a notch through which the outer peripheral side port communicates, and has a plurality of fan-shaped holes arranged in the circumferential direction on the inner peripheral side and through which the inner peripheral side port communicates,
In the check valve structure of the hydraulic shock absorber, the upper valve is provided with a plurality of oil holes arranged at equal intervals in the circumferential direction on the inner peripheral side and capable of communicating with the fan-shaped hole of the lower valve.
A check valve structure for a hydraulic shock absorber, wherein a plurality of bridges provided between adjacent fan-shaped holes of a lower valve are arranged at unequal intervals in the circumferential direction of the lower valve.   The check valve structure for a hydraulic shock absorber according to claim 1, wherein the upper valve includes six or more oil holes.   The check valve structure for a hydraulic shock absorber according to claim 1 or 2, wherein the lower valve includes three fan-shaped holes and three bridges.   The check valve structure for a hydraulic shock absorber according to claim 1 or 2, wherein the lower valve includes two fan holes and includes two bridges.

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