JP4726055B2 - Valve structure - Google Patents

Description

  The present invention relates to an improved valve structure.

  Conventionally, this type of valve structure is embodied in, for example, a piston portion of a shock absorber for a vehicle or the like, and this piston portion includes a plurality of ports provided on the same circle and each port. There is known one having an opening window formed of a recess communicating with the outlet end, a seat portion surrounding the outer periphery of the opening window, and an annular leaf valve stacked on the seat portion to open and close a port (for example, Patent Document 1).

In this valve structure, since the port Po1 allows only the flow of hydraulic oil in one direction due to the presence of the leaf valve, the flow of hydraulic oil in the reverse direction is allowed as shown in FIG. Therefore, a plurality of separate ports Po2 are generally formed by shifting in the circumferential direction from the formation position of the port Po1, and therefore, the seat portion S has a leaf valve L as shown in FIG. 6 is provided so as to protrude from the outlet end of the other port Po2 to the leaf valve L side, and the shape of the valve seat portion S viewed from the front is shown in FIG. As described above, each port Po2 has a substantially flower shape so that it can avoid another port Po2, and a single petal portion surrounds one open window W. Thereby making it possible to close the only door Po1 in the leaf valve L.
JP 2002-227903 A (paragraph number 0036, FIG. 2 (C))

  However, in the valve structure as described above, it may be pointed out that there are the following problems.

  That is, as described above, the seat portion serving as the valve seat has the above-described shape and surrounds each opening window W, so that the hydraulic oil that is going to pass through the port Po1 is an annular leaf. Only a part of the valve L is pressed.

  Therefore, the leaf valve L bends with the inner peripheral spacer K as a fulcrum under the pressure of the hydraulic oil that tries to pass through the port Po1, but the pressure acting on the leaf valve L is evenly distributed over the entire circumference. Since it does not act, the annular leaf valve L bends in the circumferential direction in addition to the bend of the spacer K fulcrum. As a result, an excessive load is applied to the leaf valve L, and a large stress is applied. As a result, the fatigue of the part of the leaf valve L that opposes each of the opening windows W becomes intense, and the durability of the leaf valve L may be reduced.

  Therefore, the present invention has been developed to improve the above-mentioned problems, and an object of the present invention is to provide a valve structure capable of improving the durability of a leaf valve.

  In order to solve the above-described object, the problem solving means in the present invention surrounds a plurality of ports provided on the same circle, a plurality of opening windows communicating with the outlet end of each port, and the outer periphery of the opening end of each opening window. A valve body including a seat portion, a contact member that contacts the seat portion and is stacked on the valve body, and a leaf valve that is stacked on the contact member. One or more grooves having a total circumferential width longer than the total circumferential width of each opening window to be formed, and a plurality of through holes communicating the inside of the groove with each opening window And

  According to the valve structure of the present invention, since the contact member is provided, the pressure acting on the leaf valve does not act on only a part of the leaf valve in the circumferential direction, but is uniform over the entire circumference. Therefore, the leaf valve does not bend in a circumferential direction.

  Therefore, in this valve structure, since the leaf valve does not bend in a circumferential direction, a large stress is not applied to the leaf valve, and an excessive load is not applied. Will be improved.

  Further, since the durability of the leaf valve is improved, the leaf valve has a long life and the reliability of the valve in which the valve structure is embodied is improved.

  The valve structure of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a part of a piston portion of a shock absorber in which a valve structure according to an embodiment is embodied. FIG. 2 is a front view of a piston portion in which the valve structure according to the embodiment is embodied. FIG. 3 is a front view of the contact member of the valve structure according to the embodiment. FIG. 4A is a front view of the contact member of the valve structure according to a modification of the embodiment. FIG. 4B is a front view of the contact member of the valve structure according to another modification of the embodiment. FIG. 5A is a front view of the leaf side member of the contact member of the valve structure according to another modification of the embodiment. FIG. 5B is a front view of the body-side member of the contact member of the valve structure according to another modification of the embodiment.

  As shown in FIG. 1, the valve structure in one embodiment is embodied as an extension-side damping valve of a piston portion of a shock absorber, and includes a plurality of ports 2 provided on the same circle and outlet ends of the respective ports 2. The piston 1 is a valve body including a plurality of opening windows 3 communicating with each other and a seat portion 4 surrounding the outer periphery of the opening end of each opening window 3, and the piston 1 is abutted on the seat portion 4 and stacked on the piston 1 which is a valve body. A contact member 20 and a leaf valve 10 stacked on the contact member 20 are provided.

  On the other hand, a shock absorber in which this valve structure is embodied is well known and will not be described in detail, but specifically, for example, a cylinder 40 and a head member (not shown) that seals the upper end of the cylinder 40. ), The rod 5 slidably penetrating the head member (not shown), the piston 1 provided at the end of the rod 5, and the upper chamber 41 and the lower chamber partitioned by the piston 1 in the cylinder 40 42 and a sealing member (not shown) for sealing the lower end of the cylinder 40, and the cylinder 40 is filled with hydraulic oil.

  When the piston 1 moves downward in FIG. 1 with respect to the cylinder 40, the valve structure is operated via the port 2 from the lower chamber 42 to the upper chamber 41 when the pressure in the lower chamber 42 increases. When the oil moves, the leaf valve 10 provides resistance to the movement of the hydraulic oil to cause a predetermined pressure loss, thereby functioning as a damping force generating element that generates a predetermined damping force in the shock absorber.

  Hereinafter, the valve structure will be described in detail. The piston 1 that is a valve body is formed in a disk shape having an insertion hole 1a through which a rod 5 of a shock absorber is inserted in an axial center portion, and a plurality of pistons 1 provided on the same circle. The port 2 includes a plurality of opening windows 3 communicating with the outlet ends of the respective ports 2, and a sheet portion 4 formed on the outer peripheral side of each opening window 3 and surrounding each opening window 3.

  In addition to the port 2, the piston 1 has a port 50 that allows the hydraulic oil to move from the upper chamber 41 to the lower chamber 42, as shown in FIG. 2. The seat portion 4 has a substantially flower shape as in the conventional valve structure, and in the drawing, the seat portion 4 is formed in four opening windows 3. Correspondingly, four petal portions 4 a are provided, one petal portion 4 a surrounds one opening window 3, and the seat portion 4 protrudes from the inlet end of the port 50 toward the leaf valve 10. Therefore, even if a contact member 20 described later is laminated on the sheet portion 4, the port 50 is not blocked.

  Further, a rod 5 is inserted into the insertion hole 1a of the piston 1, and the tip of the rod 5 is protruded upward of the piston 1 in FIG. Although not shown, the outer diameter of the tip of the rod 5 is set to be smaller than the outer diameter of the lower side (not shown), and a step portion (not shown) is formed at a portion where the outer diameters of the lower side and the tip are different. ing.

  And while inserting the contact member 20, the leaf valve 10, and the spacer 25 at the tip of the rod 5, the piston nut 30 is screwed onto the tip of the rod 5 from above the spacer 25 in FIG. The piston 1 is sandwiched between the steps of the rod 5 and fixed to the rod 5.

  Subsequently, the abutting member 20 that abuts on the seat portion 4 and is stacked on the piston 1 is formed in an annular shape to allow insertion of the rod 5 into the shaft center portion, and is shown in FIGS. 1 and 3. Thus, an annular groove 21 serving as a groove is provided at the end on the leaf valve 10 side, and a plurality of through-holes 22 for communicating the annular groove 21 and the respective opening windows 3 are provided. That is, each of the through holes 22 is opened from a portion corresponding to the opening window 3 at the end of the contact member 20 on the sheet portion 4 side, and communicates with the annular groove 21.

  In addition, as the groove | channel in the contact member 20, the total circumferential direction width | variety of each opening window 3, In this case, since the four opening windows 3 and each circumferential direction width | variety are w1, 4xw1 length and However, since the total circumferential width w2 of the annular groove 21 is longer than the total circumferential width, the groove may be the annular groove 21 as described above. Further, since the groove only needs to satisfy the above conditions, a C-shaped groove 51 as shown in FIG. 4 (A) or a plurality of arc shapes provided at predetermined equal intervals in the circumferential direction as shown in FIG. 4 (B). The groove 52 may be used.

  Further, as shown in FIGS. 5A and 5B, the contact member 20 includes a leaf side member 55 that contacts the leaf valve side and a body side member 56 that contacts the valve body side. The side member 56 is provided with the through hole 22, while the leaf side member 55 is provided with, for example, four arc-shaped holes 57, and the body side member 56 and the leaf side member 55 are overlapped to form a groove. May be formed. Of course, also in this case, the total circumferential width of each arcuate hole 57 functioning as a groove is set longer than the total circumferential width of the opening window 3. Thus, by forming the contact member 20 with the two members of the leaf member 55 and the body side member 56, the process of forming the through hole and the groove in the contact member 20 is a drilling process. This is advantageous in that the processing cost is reduced.

  Also in this case, the arc-shaped holes 57 may be, for example, C-shaped as in FIG. 4A, and the number thereof may be four or less as long as the above conditions are satisfied. 4 and 5, the total circumferential width of the groove is preferably as long as possible.

  The abutting member 20 configured as described above is laminated on the piston 1 with the end portion side where the through hole 22 is opened in the lower side in FIG. 1. The leaf valve 10 is further laminated.

  The leaf valve 10 is formed in an annular shape to allow the insertion of the rod 5 into the shaft center portion, and the outer diameter thereof is a diameter capable of closing the annular groove 21 of the contact member 20. Yes.

  That is, by closing the annular groove 21 with the leaf valve 10, the port 2 can also be closed, and the operation to move from the lower chamber 42 to the upper chamber 41 via the port 2 is performed. By receiving the pressure from the oil and bending, the port 2 can be opened away from the contact member 20.

  In this case, the leaf valve 10 is constituted by a single annular plate, but may be constituted by laminating an arbitrary number of annular plates depending on the damping characteristics realized by the present valve structure.

  Next, the operation of the valve structure will be described. As described above, when the piston 1 moves downward in FIG. 1 with respect to the cylinder 40, the pressure in the lower chamber 42 increases, and the hydraulic oil in the lower chamber 42 increases. It tries to move into the upper chamber 41 through the port 2.

  At this time, the pressure due to the hydraulic oil also acts in the annular groove 21 of the abutting member 20 through the through hole 22, so the pressure of the hydraulic oil that acts to push up the leaf valve 10 in FIG. With the pressure of the hydraulic oil in the groove 21, the leaf valve 10 receives this pressure and the outer peripheral side of the leaf valve 10 bends upward in FIG. 1 to separate from the contact member 20 and opens the port 2. . The hydraulic oil moves from the lower chamber 42 to the upper chamber 41 through a gap formed between the leaf valve 10 and the contact member 20, and the shock absorber is subjected to pressure loss that occurs when the hydraulic oil passes through the gap. Proper damping force will be generated.

  As described above, the pressure acting on the leaf valve 10 does not act only on a part of the leaf valve 10 in the circumferential direction, but acts uniformly over the entire circumference. The spacer 25 is bent as a fulcrum and no longer bends in the circumferential direction.

  Therefore, in this valve structure, the leaf valve 10 does not bend in the circumferential direction, so that a large stress does not act on the leaf valve 10 and an unreasonable load is not applied. The durability of 10 will be improved.

  Further, since the durability of the leaf valve 10 is improved, the leaf valve 10 has a long life, and the reliability of the valve in which the valve structure is embodied is improved.

  The contact member 20 basically has a force obtained by multiplying the area obtained by dividing the opening area of the opening window 3 from the opening area of the through hole 22 facing the opening window 3 by the hydraulic oil pressure from the lower side in FIG. If the cross-sectional area of the receiving hole 22 is made larger than the port 2 as much as possible, no pressure loss occurs in the through hole 22. Moreover, it is good to make the cross-sectional area of the annular groove 21 large, and to maintain the state pressed against the piston 1 side.

  By increasing the cross-sectional area of the annular groove 21, the contact member 20 is bent together with the leaf valve 10 and is separated from the seat portion 4 of the piston 1 which is the valve body, and a large load is applied to the leaf valve 10. Therefore, it is possible to prevent the risk of causing the bending in the circumferential direction.

  Moreover, since the groove is the annular groove 21 and the total circumferential width w2 of the groove is set to be the longest in the above-described case, an extremely high effect can be obtained. Also in the configuration of the abutting member 20 as shown in FIG. 5, since the total circumferential width w2 of the groove is set to be longer than the total circumferential width of the opening window 3, the leaf valve 10 The acting pressure acts more uniformly over the entire circumference than when receiving pressure directly from the opening window 3 via the contact member 20, and the leaf valve 10 bends with the spacer 25 as a fulcrum. , It will not bend in a circumferential direction.

  Therefore, even if the valve structure is configured in this way, the leaf valve 10 is restrained from being bent in the circumferential direction, so that a large stress does not act on the leaf valve 10 and an unreasonable load is not applied. As a result, the durability of the leaf valve 10 is improved, and further, the leaf valve 10 has a long life and the reliability of the valve in which the valve structure is embodied is improved.

  This is the end of the description of the embodiment of the valve structure, but the valve structure of the present invention can be embodied in the compression side damping valve of the piston portion of the shock absorber, or in the base valve portion. Of course, the present invention can be applied to a damping valve that functions as a damping force generating element that generates a damping force.

 It should be noted that the scope of the present invention is not limited to the details shown or described.

It is a longitudinal cross-sectional view in a part of piston part of the shock absorber in which the valve structure in one embodiment was embodied. It is a front view of the piston part in which the valve structure in one embodiment was embodied. It is a front view of the contact member of the valve structure in one embodiment. (A) It is a front view of the contact member of the valve structure in the modification of one embodiment. (B) It is a front view of the contact member of the valve | bulb structure in the other modification of one Embodiment. (A) It is a front view of the leaf side member of the contact member of the valve | bulb structure in another modification of one Embodiment. (B) It is a front view of the body side member of the contact member of the valve | bulb structure in another modification of one Embodiment. It is a front view of the piston part of the conventional valve structure. It is a longitudinal cross-sectional view of the piston part of the conventional valve structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piston 1a which is a valve body Insertion hole 2 Port 3 Opening window 4 Seat part 4a Petal part 5 Rod 10 Leaf valve 20 Interposition member 21 Annular groove 22 Through hole 25 Spacer 30 Piston nut 40 Cylinder 41 Upper chamber 42 Lower chamber 50 Port 51 C-shaped groove 52 as a groove 52 Arc-shaped groove 55 Leaf-side member 56 Body-side member 57 Arc-shaped hole

Claims (3)

A valve body having a plurality of ports provided on the same circle, a plurality of opening windows communicating with the outlet ends of the respective ports, a seat portion surrounding the outer periphery of the opening end of each opening window, and a valve in contact with the seat portion An abutting member laminated on the body and a leaf valve laminated on the abutting member, the abutting member being a total circumference longer than the total circumferential width of each opening window formed at the leaf valve side end A valve structure comprising one or more grooves having a width in the direction and a plurality of through holes communicating the inside of the grooves with the respective opening windows. The contact member includes a leaf side member that contacts the leaf valve side end and a body side member that contacts the valve body side, the arc side hole is provided in the leaf side member, and the through hole is provided in the body side member. The valve structure according to claim 1, characterized in that: The valve structure according to claim 1, wherein the groove is an annular groove.

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