JP5933345B2 - Shock absorber - Google Patents

Description

  The present invention relates to a shock absorber.

  Some disc valves provided in a shock absorber have an inner annular portion, an outer annular portion, and a support portion along the radial direction that connects them (for example, see Patent Document 1).

JP-A-6-129469

  In the above disk valve, if the rigidity of the support part is increased in consideration of durability, the outer annular part may not be able to open sufficiently and proper valve characteristics may not be obtained. If the rigidity of the support portion is lowered, the durability may be lowered.

  Therefore, an object of the present invention is to provide a shock absorber capable of optimizing valve characteristics while suppressing a decrease in durability.

In order to achieve the above object, according to the present invention, the disc valve includes an outer annular portion, an inner annular portion, and two support portions that connect the outer annular portion and the inner annular portion. The two support portions of the book are connected to the outer annular portion at two locations on the same side from the center in the radial direction of the disc valve and spaced apart in the circumferential direction of the disc valve. And two inner connecting portions arranged on the same opposite side from the center in the radial direction of the disc valve and spaced in the circumferential direction of the disc valve are connected to the inner annular portion, Two connecting arm portions are provided so as to connect the outer connection portion and the inner connection portion close to the circumferential direction of the valve, and the interval between the two inner connection portions is the two outer portions. The configuration is wider than the interval between the connecting portions .

  According to the present invention, it is possible to optimize the valve characteristics while suppressing a decrease in durability.

It is a fragmentary sectional view showing a buffer of one embodiment concerning the present invention. It is sectional drawing which shows the base valve of the buffer of one Embodiment which concerns on this invention. It is a top view which shows the disk valve of the buffer of one Embodiment which concerns on this invention.

  A shock absorber according to an embodiment of the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the shock absorber of this embodiment has a cylinder 11 in which a fluid such as liquid or gas is enclosed. The cylinder 11 includes an inner cylinder 12 and an outer cylinder 13 having a larger diameter than the inner cylinder 12 and concentrically provided so as to cover the inner cylinder 12, and between the inner cylinder 12 and the outer cylinder 13. It has a double cylinder structure in which the reservoir chamber 14 is formed.

  A piston 17 is slidably fitted in the inner cylinder 12 of the cylinder 11. The piston 17 defines an upper chamber 18 and a lower chamber 19 in the inner cylinder 12, that is, in the cylinder 11. Specifically, in the cylinder 11, hydraulic fluid as a fluid is sealed in the upper chamber 18 and the lower chamber 19, and hydraulic fluid and gas as a fluid are sealed in the reservoir chamber 14.

  In the cylinder 11, the other end of a rod 22 whose one end extends to the outside of the cylinder 11 is inserted into the inner cylinder 12, and the piston 17 has a nut 23 at the other end in the inner cylinder 12 of the rod 22. It is concluded by Although not shown, one end side of the rod 22 is inserted through a rod guide and an oil seal attached to the upper ends of the inner cylinder 12 and the outer cylinder 13 and extends to the outside.

  The rod 22 has a main shaft portion 25 and an attachment shaft portion 26 at the inner end portion of the cylinder 11 and having a smaller diameter than the main shaft portion 25, so that the main shaft portion 25 has an end on the attachment shaft portion 26 side. A step surface 27 is formed along the direction orthogonal to the axis. The attachment shaft portion 26 is formed with a male screw 28 for screwing the nut 23 into a predetermined range on the opposite side to the main shaft portion 25.

  The piston 17 is fitted in the inner cylinder 12 of the cylinder 11 to partition the inner cylinder 12 into two chambers, an upper chamber 18 and a lower chamber 19, and an outer periphery of the piston valve body 31. A sliding contact member 32 is mounted on the surface and slidably contacts the inner cylinder 12. The piston valve body 31 is formed with a cylindrical portion 34 projecting in the axial direction on the outer peripheral side on the lower chamber 19 side.

  The piston valve body 31 is formed in an annular shape with a through hole 35 through which the attachment shaft portion 26 of the rod 22 is inserted in the center in the radial direction. The piston valve body 31 includes an annular boss 36 that protrudes in the axial direction so as to surround the through-hole 35 on the outer side in the radial direction, and a radial boss on the opposite side of the cylindrical portion 34 in the axial direction. An annular inner sheet portion 37 that protrudes in the axial direction outside the portion 36 and an annular outer sheet portion 38 that protrudes in the axial direction outside the radially inner sheet portion 37 are formed. Furthermore, the piston valve body 31 has an annular boss portion 40 projecting in the axial direction outside the radial through-hole 35 on the side of the cylindrical portion 34 in the axial direction, and a boss portion 40 in the radial direction. An annular sheet portion 41 protruding in the axial direction on the outer side and the inner side of the cylindrical portion 34 is formed.

  Here, in the axial direction of the piston valve body 31, the boss portion 36, the inner seat portion 37 and the outer seat portion 38 have the same height position, and the seat portion 41 protrudes from the boss portion 40. The direction height is slightly higher.

  One end of the piston valve body 31 in the axial direction is opened between the boss portion 36 and the inner seat portion 37, and the other end is opened between the boss portion 40 and the seat portion 41 so as to penetrate in the axial direction. A plurality of holes 43 are formed at intervals in the circumferential direction (only one place is shown in FIG. 1 because of the cross section). The piston valve body 31 has one axial end opened between the inner seat portion 37 and the outer seat portion 38 and the other end opened between the seat portion 41 and the cylindrical portion 34 in the axial direction. A plurality of communication holes 44 penetrating therethrough are formed at intervals in the circumferential direction (only one location is shown in FIG. 1 because of the cross section).

  The inner communication hole 43 communicates between the upper chamber 18 and the lower chamber 19, and forms one flow path 45 through which hydraulic fluid flows between the upper chamber 18 and the lower chamber 19. Yes. The outer communication hole 44 communicates between the two chambers of the upper chamber 18 and the lower chamber 19, and forms the other channel 46 through which the working fluid flows between the upper chamber 18 and the lower chamber 19. Yes. Therefore, these flow paths 45 and 46 are provided in the piston valve body 31. The piston valve body 31 is formed with an inner seat portion 37 on the center side (inner periphery side) and an outer seat portion 38 on the outer periphery side with the communication hole 44 in between.

  The piston 17 has a disc valve 50, a spacer 51, and a regulating member 52 in order from the piston valve body 31 side on the cylindrical portion 34 side in the axial direction of the piston valve body 31. The piston 17 has a disc valve 55, a spacer 56, a spring member 57, and a regulating member 58 in order from the piston valve body 31 side on the side opposite to the cylindrical portion 34 in the axial direction of the piston valve body 31. Yes.

  A rod insertion hole 60 is formed at the center of the disk valve 50 in the radial direction, a rod insertion hole 61 is formed at the center of the spacer 51 in the radial direction, and a rod insertion hole 62 is formed at the center of the restriction member 52 in the radial direction. It is formed to penetrate through. In addition, a rod insertion hole 63 is provided at the center of the disk valve 55 in the radial direction, a rod insertion hole 64 is provided at the center of the spacer 56 in the radial direction, and a rod insertion hole 65 is provided at the center of the spring member 57 in the radial direction. In the center of the member 58 in the radial direction, rod insertion holes 66 are formed penetrating in the axial direction.

  The rod 22 has a mounting shaft portion 26 that passes through the rod insertion hole 66 of the regulating member 58, the rod insertion hole 65 of the spring member 57, the rod insertion hole 64 of the spacer 56, the rod insertion hole 63 of the disc valve 55, and the piston valve body 31. The nut 23 is screwed into the male screw 28 through the hole 35, the rod insertion hole 60 of the disc valve 50, the rod insertion hole 61 of the spacer 51, and the rod insertion hole 62 of the regulating member 52. Thereby, the inner peripheral side of the regulating member 58, the inner peripheral side of the spring member 57, the spacer 56, the inner peripheral side of the disc valve 55, the inner peripheral side of the piston valve body 31, the inner peripheral side of the disc valve 50, the spacer 51 and The inner peripheral side of the regulating member 52 is clamped in the axial direction by the step surface 27 of the main shaft portion 25 of the rod 22 and the nut 23.

  The disc valve 50, the spacer 51, the regulating member 52, the disc valve 55, the spacer 56, the spring member 57 and the regulating member 58 are moved in the radial direction with respect to the rod 22 and the piston valve body 31 by the mounting shaft portion 26 of the rod 22. It is regulated.

  The disc valve 50 on the lower chamber 19 side has an outer diameter slightly larger than that of the seat portion 41, and abuts against the boss portion 40 and the seat portion 41 of the piston valve body 31 to close the inner flow path 45. . When the rod 22 moves to the extending side to increase the amount of protrusion that protrudes from the cylinder 11, the pressure of the upper chamber 18 is higher than that of the lower chamber 19 by the piston 17 that moves together with the rod 22. Accordingly, the flow path 45 is opened by separating from the seat portion 41. Thereby, in the inner flow path 45 provided in the piston valve body 31, when the rod 22 moves to the extension side, the fluid flows from the upper chamber 18 to the lower chamber 19, and the disc valve 50 This is a disk valve on the extension side that opens and closes the flow path 45. The fluid flows through the flow path 45 when the rod 22 and the piston 17 are moved to the extension side.

  The outer diameter of the spacer 51 is smaller than the outer diameter of the disc valve 50 and is substantially the same as the outer diameter of the boss portion 40. The regulating member 52 has an outer diameter larger than the outer diameter of the spacer 51 and slightly smaller than the outer diameter of the disc valve 50. When the disc valve 50 is deformed by a predetermined amount in a direction away from the seat portion 41, the regulating member 52 abuts on the disc valve 50 and regulates further deformation.

  The outer diameter of the disk valve 55 on the upper chamber 18 side is slightly larger than that of the outer seat portion 38 of the piston valve body 31. The disc valve 55 has a notch 68 formed radially inward from the contact position with the inner seat portion 37, and the inner flow path 45 is always in communication with the upper chamber 18 through the notch 68. Yes.

  The disc valve 55 contacts the boss portion 36, the inner seat portion 37, and the outer seat portion 38 of the piston valve body 31 to close the outer flow path 46. When the rod 22 moves to the contraction side that increases the amount of entry into the cylinder 11, the pressure of the lower chamber 19 is increased by the piston 17 that moves together with the rod 22, so that the pressure is lower than the upper chamber 18. The outer flow path 46 is opened away from the seat portion 38. Thereby, in the outer flow path 46 provided in the piston valve body 31, when the rod 22 moves to the contraction side, the fluid flows from the lower chamber 19 to the upper chamber 18, and the disc valve 55 This is a contraction-side disk valve that opens and closes the flow path 46. When the rod 22 and the piston 17 are thus moved to the contraction side, the fluid flows through the flow path 46.

  The spring member 57 includes a flat disk-like base 67 having a rod insertion hole 65 formed in the center, and a plurality of elastic points extending obliquely outward from the outer periphery of the base 67 in the radial direction and on one side in the axial direction. A plate-like spring composed of the legs 70 is formed. The spring member 57 is clamped to the spacer 56 and the restricting member 58 at the base 67, and abuts against the disc valve 55 at the tip ends of a plurality of elastic legs 70 extending radially outward from the spacer 56. To the piston valve body 31.

  The regulating member 58 has an outer diameter substantially the same as the outer diameter of the disk valve 55. The restricting member 58 is formed with a plurality of communication holes 69 that are in communication with the upper chamber 18 through the notch 68 and are provided with a plurality of holes in the axial direction at intervals in the circumferential direction. Yes. When the disc valve 55 is deformed by a predetermined amount in a direction away from the outer seat portion 38, the regulating member 58 abuts on the disc valve 55 and regulates further deformation.

  The outer cylinder 13 includes a cylindrical cylindrical member 72 and a bottom lid member 73 that is fitted to the lower end of the cylindrical member 72 and closes the opening at the lower end. The bottom cover member 73 is fitted to the inner peripheral portion of the cylindrical member 72 at the outer peripheral portion, and in this state, has a stepped shape so as to be positioned on the outer side in the axial direction toward the center side. The bottom cover member 73 is fixed to the cylindrical member 72 in a sealed state by welding.

  A lower chamber 19 and the above-described reservoir chamber 14 are defined in the cylinder 11 at the lower end portion of the inner cylinder 12, and a damping valve that generates a contraction-side damping force, and an extension side from the reservoir chamber 14 to the lower chamber 19. A base valve 71 having a suction valve for flowing hydraulic fluid without substantially generating a damping force is provided therein.

  The base valve 71 has an annular base valve body (valve body) 76 that is fitted into the inner cylinder 12 of the cylinder 11 and partitions the inside of the cylinder 11 into two chambers, a lower chamber 19 and a reservoir chamber 14. The base valve body 76 is made of sintered metal, and a stepped portion 77 having a smaller diameter than the lower portion is formed on the outer peripheral portion of the upper portion. The stepped portion 77 is fitted to the inner peripheral portion of the lower end of the inner cylinder 12. To do. The base valve body 76 has an annular projecting foot 78 projecting in the axial direction on the outer peripheral side of the lower portion, and abuts against the bottom lid member 73 at the projecting foot 78. A plurality of flow passage grooves 79 penetrating in the radial direction are formed in the protruding foot 78 at intervals in the circumferential direction. A range from the inner cylinder 12 and the outer cylinder 13 to the area between the base valve 71 and the bottom cover member 73 is communicated with the flow path groove 79 to form the reservoir chamber 14.

  As shown in FIG. 2, the base valve body 76 is formed in such a manner that a through hole 81 penetrates in the center in the radial direction in the axial direction, thereby forming an annular shape. Further, the base valve body 76 has a boss 84 projecting in an annular shape in the axial direction so as to surround the through-hole 81 on the outer side in the radial direction, and a boss in the radial direction on the opposite side to the projecting foot 78 in the axial direction. An annular inner sheet portion 85 that protrudes in the axial direction outside the portion 84 and an annular outer sheet portion 86 that protrudes in the axial direction outside the radially inner sheet portion 85 are formed. Further, the base valve body 76 includes an annular boss 88 projecting in the axial direction so as to surround the through hole 81 on the radially outer side, and a radial boss 88 on the projecting foot 78 side in the axial direction. Further, an annular seat portion 89 that protrudes in the axial direction on the outer side and on the inner side of the protruding foot portion 78 is formed.

  In the axial direction of the base valve body 76, the boss portion 84, the inner seat portion 85, and the outer seat portion 86 have the same height position. Further, the sheet portion 89 is slightly higher in the protruding direction than the boss portion 88.

  One end of the base valve body 76 in the axial direction opens between the boss portion 84 and the inner seat portion 85, and the other end opens between the boss portion 88 and the seat portion 89, and is a communication hole that penetrates in the axial direction. 92 is formed at a plurality of locations at intervals in the circumferential direction (only one location is shown in FIG. 2 because of the cross section). Further, one end of the base valve body 76 in the axial direction opens between the inner seat portion 85 and the outer seat portion 86, and the other end opens between the seat portion 89 and the protruding foot portion 78. A plurality of communication holes 93 penetrating therethrough are formed at intervals in the circumferential direction (in FIG. 2, only one location is shown because of the cross section).

  The inner communication hole 92 communicates between the lower chamber 19 and the reservoir chamber 14, and forms one flow path 94 through which the working fluid flows between the lower chamber 19 and the reservoir chamber 14. Yes. The outer communication hole 93 communicates between the two chambers of the lower chamber 19 and the reservoir chamber 14, and forms the other flow path 95 through which the working fluid flows between the lower chamber 19 and the reservoir chamber 14. Yes. Therefore, these flow paths 94 and 95 are provided in the base valve body 76. The base valve body 76 is formed with an inner seat 85 on the center side (inner circumference) and an outer seat 86 on the outer circumference with the communication hole 93 in between.

  The base valve 71 has a pin member 98, and the pin member 98 is provided with a columnar shaft portion 99 inserted into the through hole 81 of the base valve body 76, and a shaft portion 99 provided at one end of the shaft portion 99. Also has a large-diameter disk-shaped head 100. In addition, a diameter-expanded portion 101 that is larger in diameter than the shaft portion 99 is formed by caulking at the other end of the shaft portion 99 opposite to the head portion 100.

  The base valve 71 has a disc valve 103 that acts as a damping valve, a spacer 104, and a regulating member 105 in this order from the base valve body 76 side on the protruding foot 78 side in the axial direction of the base valve body 76. Further, the base valve 71 is arranged on the opposite side of the base valve body 76 from the axial projecting foot 78, in order from the base valve body 76 side, the disk valve 107 acting as a suction valve, the spacer 108, the spring member 109, and the restriction. A member 110 is provided.

  A pin insertion hole 112 is formed at the center of the disk valve 103 in the radial direction, a pin insertion hole 113 is formed at the center of the spacer 104 in the radial direction, and a pin insertion hole 114 is formed at the center of the restriction member 105 in the radial direction. As a result, both of these are formed in a ring shape. Further, a pin insertion hole 116 is provided at the center of the disk valve 107 in the radial direction, a pin insertion hole 117 is provided at the center of the spacer 108 in the radial direction, and a pin insertion hole 118 is provided at the center of the spring member 109 in the radial direction. In the center of the member 110 in the radial direction, pin insertion holes 119 are formed penetrating in the axial direction, respectively. As a result, both of them have an annular shape.

  The shaft portion 99 before caulking of the pin member 98 includes the pin insertion hole 114 of the restriction member 105, the pin insertion hole 113 of the spacer 104, the pin insertion hole 112 of the disk valve 103, the through hole 81 of the base valve body 76, The disc valve 107 is inserted through the pin insertion hole 116, the pin insertion hole 117 of the spacer 108, the pin insertion hole 118 of the spring member 109, and the pin insertion hole 119 of the restriction member 110 in this order, and in this state, protrudes from the restriction member 110. The end of the shaft 99 that is opposite to the head 100 is crimped to the head 100 side. Then, since the movement of the regulating member 105, the spacer 104, the disc valve 103, the base valve body 76, the disc valve 107, the spacer 108, the spring member 109, and the regulating member 110 is regulated by the head 100, these are axially arranged. The diameter of the shaft portion 99 is increased so that the diameter-expanded portion 101 is formed so as to be sandwiched therebetween. In this way, the inner peripheral side of the regulating member 105, the spacer 104, the inner peripheral side of the disc valve 103, the inner peripheral side of the base valve body 76, the inner peripheral side of the disc valve 107, the spacer 108, and the inner periphery of the spring member 109. The inner peripheral side of the regulating member 110 is clamped in the axial direction by the head 100 and the enlarged diameter portion 101 of the pin member 98.

  The disc valve 103, the spacer 104, the regulating member 105, the disc valve 107, the spacer 108, the spring member 109, and the regulating member 110 are moved in the radial direction with respect to the pin member 98 and the base valve body 76 by the shaft portion 99 of the pin member 98. Is regulated.

  The disk valve 103 on the reservoir chamber 14 side is configured by stacking a plurality of perforated disk-shaped single-plate disks having the same outer diameter in the axial direction, and the outer diameter is the outer diameter of the seat portion 89. The diameter is slightly larger, and the outer peripheral side comes into contact with the sheet portion 89 to close the inner flow path 94. The disc valve 103 is separated from the seat portion 89 shown in FIG. 2 when the rod 22 shown in FIG. 1 moves to the contraction side and the piston 17 moves to the lower chamber 19 side and the pressure in the lower chamber 19 rises. Then, the inner flow path 94 is opened. As a result, the inner flow path 94 provided in the base valve body 76 causes the fluid to flow from the lower chamber 19 toward the reservoir chamber 14 when the rod 22 moves to the contraction side. The flow path 94 is opened and closed to form a compression side disk valve that generates a damping force. Thus, the fluid flows through the flow path 94 when the rod 22 and the piston 17 move to the contraction side. The disc valve 103 has a lower chamber so as to discharge the excess liquid mainly generated by the rod 22 entering the cylinder 11 because of the relationship with the disc valve 55 on the contraction side provided in the piston 17 shown in FIG. The function of flowing the liquid from 19 to the reservoir chamber 14 is achieved. The disk valve on the contraction side may be a relief valve that relieves pressure when the cylinder internal pressure increases.

  As shown in FIG. 2, the outer diameter of the spacer 104 is smaller than the outer diameter of the disc valve 103 and slightly smaller than the outer diameter of the boss portion 88. The regulating member 105 has an outer diameter that is slightly smaller than the outer diameter of the disc valve 103 and substantially the same diameter as the seat portion 89. When the disc valve 103 is deformed by a predetermined amount in a direction away from the seat portion 89, the regulating member 105 abuts on the outer peripheral side of the disc valve 103 and regulates further deformation.

  The disk valve 107 on the lower chamber 19 side is formed by stamping from a single plate member, and has a flat plate shape. As shown in FIG. 3, the disk valve 107 includes an inner annular portion 122 that forms an annular shape by forming the pin insertion hole 116 in the center, and an outer surface that forms an annular shape having a larger diameter than the inner annular portion 122. The annular portion 123 is composed of two support portions 124 and 124 that connect the inner annular portion 122 and the outer annular portion 123 in a concentric state.

  The two support portions 124 and 124 are formed as outer annular portions at outer connection portions 126 and 126 that are disposed on the same side of the disk valve 107 in the radial direction and spaced from each other in the circumferential direction of the disk valve 107. 123. In addition, the two support portions 124 and 124 are formed as inner annular portions at inner connection portions 127 and 127 disposed at intervals in the circumferential direction of the disk valve on the opposite side of the center in the radial direction of the disk valve. 122 is connected. Further, the two support portions 124 and 124 have connecting arm portions 128 and 128 that connect the outer connection portion 126 and the inner connection portion 127 on the side closer to the disk valve 107 in the circumferential direction, respectively. In other words, with respect to the center of the disc valve 107, two outer connection portions 126, 126 are provided on the same one side in the radial direction of the disc valve 107, and two inner connection portions 127, 127 are provided on the same opposite side. Two connecting arm portions 128 are provided so as to connect the outer connecting portion 126 and the inner connecting portion 127 close to the circumferential direction of the disc valve 107. Note that the distance between the two inner connection portions 127 and 127 in the circumferential direction of the disc valve 107 is wider than the distance between the two outer connection portions 126 and 126.

  In each of the two support portions 124, 124, the outer connection portion 126 protrudes from the inner peripheral portion of the outer annular portion 123 to the front of the inner annular portion 122 substantially along the radial direction of the disc valve 107. The portion 127 protrudes almost along the radial direction of the disc valve 107 from the outer peripheral portion of the inner annular portion 122 to the front of the outer annular portion 123, and the connecting arm portion 128 connects these tips. The connecting arm portion 128 is between the inner peripheral portion of the outer annular portion 123 and the outer peripheral portion of the inner annular portion 122 and has an arc shape along these, and the inner peripheral portion of the outer annular portion 123 and the inner annular portion 122. It is formed at a position equidistant from the outer periphery in the radial direction.

  As described above, the disc valve 107 branches from the inner peripheral portion of the outer annular portion 123 toward the inner annular portion 122 between the two inner connection portions 127 and 127 and then branches in the circumferential direction of the disc valve 107. Thus, the substantially Y-shaped gap 130 extending in an arc shape along the outer peripheral portion of the inner annular portion 122 and the outer sides of the two outer connection portions 126 and 126 in the circumferential direction of the disc valve 107 are connected to each other. A C-shaped gap 131 extending in an arc shape is formed along the inner peripheral portion of the outer annular portion 123.

  As shown in FIG. 2, the disc valve 107 has an outer diameter of the inner annular portion 122 that is substantially the same as the outer diameter of the boss portion 84 and the outer diameter of the spacer 108. Clamping is performed on the boss portion 84 and the spacer 108 located on the center side of the base valve body 76 with respect to the inner seat portion 85. In the disc valve 107, the outer diameter of the outer annular portion 123 is slightly larger than the outer diameter of the outer seat portion 86, and the inner diameter of the outer annular portion 123 is slightly larger than the inner diameter of the inner seat portion 85. It has a small diameter. Therefore, the outer annular portion 123 simultaneously contacts the outer seat portion 86 and the inner seat portion 85 to close the outer flow path 95, thereby forming a valve chamber 133 between the inner seat portion 85 and the outer seat portion 86. Further, the disc valve 107 is formed by deforming the two support portions 124 between the inner annular portion 122 and the outer annular portion 123 so that the outer annular portion 123 is separated from the outer seat portion 86 and the inner seat portion 85. Separate. That is, the disc valve 107 is disposed so as to be able to be separated from and connected to the inner seat portion 85 and the outer seat portion 86.

  As described above, the outer annular portion 123 of the disc valve 107 abuts against the inner seat portion 85 and the outer seat portion 86 of the base valve body 76 to close the outer flow path 95 to form the valve chamber 133. In the disc valve 107, when the rod 22 shown in FIG. 1 moves to the extension side, the piston 17 moves to the upper chamber 18 side, and the pressure in the lower chamber 19 decreases, the outer annular portion 123 becomes the outer seat portion 86 and the inner seat. The flow path 95 is opened away from the portion 85. As a result, the outer flow path 95 provided in the base valve body 76 allows fluid to flow from the reservoir chamber 14 toward the lower chamber 19 when the rod 22 moves to the extension side, and the disc valve 107 This is a disk valve on the extension side that opens and closes the flow path 95.

  Here, the outer annular portion 123 of the disc valve 107 is connected to the inner annular portion 122 fixed to the base valve body 76 via the two support portions 124, 124. Is the highest, and the rigidity at the position opposite to the connecting position of the outer connecting portions 126, 126 in the radial direction is the lowest. Therefore, when the outer annular portion 123 opens the flow path 95, initially, a position having a low rigidity on the opposite side in the radial direction from the connection position of the outer connection portions 126 and 126 is opened, and then the valve opening amount is increased. When the pressure balance is balanced with the connection position of the outer connecting portions 126 and 126 having high rigidity, the whole opens. In this way, by changing the valve opening amount gradually and continuously, abnormal noise caused by differential pressure fluctuation is suppressed.

  The disc valve 107 is connected to the lower chamber 19 from the reservoir chamber 14 so as to compensate for the shortage of liquid mainly due to the protrusion of the rod 22 from the cylinder 11 due to the relationship with the disc valve 50 on the extension side provided in the piston 17. The function of flowing the liquid substantially without resistance (to the extent that no damping force is generated) is achieved. Thus, the fluid flows through the flow channel 95 when the rod 22 and the piston 17 move to the extension side.

  The spring member 109 abuts against the outer annular portion 123 of the disc valve 107 and presses it in the axial direction to abut against the outer seat portion 86 and the inner seat portion 85 of the base valve body 76. The spring member 109 has a flat disk-shaped base 135 having a circular pin insertion hole 118 formed in the center, and a plurality of locations extending obliquely outward from the outer periphery of the base 135 in the radial direction and on one side in the axial direction. This is a plate-like spring composed of the elastic legs 136. The spring member 109 is clamped to the spacer 108 and the regulating member 110 at the base 135, and contacts the outer annular portion 123 of the disc valve 107 at the tips of the elastic legs 136 that extend radially outward from the spacer 108. Touch.

  Here, the elastic leg 136 of the spring member 109 has a spring constant set to a minimum, and even if the elastic leg 136 is deformed, the minimum attachment necessary to bring the disc valve 107 into contact with the inner seat portion 85 and the outer seat portion 86. Only power is generated. For this reason, the outer annular portion 123 of the disc valve 107 can reliably close the flow path 95 with the urging force of the elastic leg 136 if the pressure in the lower chamber 19 is equal to or higher than the pressure in the reservoir chamber 14. When the pressure in the lower chamber 19 is lower than the pressure in the reservoir chamber 14, the flow path 95 is immediately opened away from the inner sheet portion 85 and the outer sheet portion 86 while pressing the elastic legs 136 that are easily deformable. Thus, the disc valve 107 itself is a check valve that does not substantially generate a damping force.

  The restricting member 110 has an abutting portion 138 that protrudes toward the disk valve 107 in the axial direction on the outer diameter side. The contact portion 138 is slightly smaller than the outer diameter of the outer annular portion 123 of the disc valve 107 and is substantially the same diameter as the outer seat portion 86, so that the spring member 109 is not sandwiched between the disc valve 107. The outer annular portion 123 of the disc valve 107 can be abutted and stopped. The restricting member 110 has a communication hole 139 that penetrates in the axial direction and constantly communicates the inner flow path 94 with the lower chamber 19 shown in FIG. 2 via the gaps 130 and 131 shown in FIG. A plurality of locations are formed at intervals in the direction. When the outer annular portion 123 of the disc valve 107 is deformed by a predetermined amount in the direction away from the inner seat portion 85 and the outer seat portion 86 of the base valve body 76, the restricting member 110 contacts the outer annular portion 123 of the disc valve 107. It abuts at 138 and restricts further deformation.

  According to the shock absorber of the present embodiment described above, the two support portions 124 of the disk valve 107 are provided, and these two support portions 124 and 124 are arranged on the outer side on one side with respect to the radial direction of the disk valve 107. Since it is connected to the annular portion 123 and connected to the inner annular portion 122 on the opposite side, the widths of the two support portions 124 and 124 can be narrowed to increase the length. Therefore, it is possible to reduce the rigidity of the support portions 124 and 124 while suppressing a decrease in durability. By reducing the rigidity of the support portions 124, the outer annular portion 123 can be opened sufficiently, and the valve characteristics can be optimized.

  In other words, in order to reduce the rigidity of the support part, if the width is simply narrowed or the plate thickness is made thin, the strength will be insufficient and the durability will be reduced such as cracking. According to the embodiment, such a decrease in durability is not caused. Further, when the opening amount of the disk valve 107 is insufficient, the flow rate of the flow path 95 is insufficient, and as a result, the pressure loss increases and cavitation may occur, and the damping force waveform may be disturbed. Since the hydraulic fluid can flow through the flow path 95 at a large flow rate, the pressure loss and cavitation caused by the pressure loss can be suppressed, the damping force waveform becomes smooth, and the valve characteristics can be optimized. Of course, when it is not necessary to increase the flow rate, the thickness of the disk valve 107 can be increased correspondingly, which is advantageous in terms of strength and can improve durability.

  In addition, if a floating type disc valve that moves in the axial direction relative to the base valve body is adopted, the valve opening amount can be secured. This may cause abnormal noise, and may cause another problem that the accuracy management of the disk valve is complicated and the assemblability deteriorates. As described above, the shock absorber according to the present embodiment gradually changes the valve opening amount so that the differential pressure fluctuation becomes gradual, and the abnormal noise caused by the differential pressure fluctuation can be suppressed. Further, since the inner annular portion 122 is clamped, the accuracy management of the disc valve 107 is easy and the assemblability is good.

  In the above embodiment, the configuration of the disk valve 107 can be applied to the disk valve 55 of the piston 17. Furthermore, the configuration of the disk valve 107 can be applied to a valve externally attached to the cylinder 11.

  In the embodiment described above, a communication hole that communicates between the two chambers is formed, and a valve body in which an inner seat portion is formed on the center side and an outer seat portion is formed on the outer peripheral side across the communication hole, A shock absorber comprising an annular disc valve that is controlled to move in a radial direction with respect to the valve body and is detachably attached to the inner seat portion and the outer seat portion. The disc valve includes the inner seat portion. And an outer annular portion that forms a valve chamber by the outer seat portion, an inner annular portion that is clamped to the center side of the inner seat portion, and two that connect the outer annular portion and the inner annular portion. The two support portions are connected to the outer annular portion on one side and to the inner annular portion on the opposite side with respect to the radial direction of the disc valve. To. Thereby, the support part of the disk valve is made into two, in order to connect these two support parts to the outer annular part on one side and the inner annular part on the opposite side with respect to the radial direction of the disk valve. The width of the two support portions can be narrowed to increase the length. Therefore, it is possible to reduce the rigidity of the support portion while suppressing a decrease in durability. By reducing the rigidity of the support portion, the outer annular portion can be sufficiently opened, and the valve characteristics can be optimized.

18 Upper room (room)
19 Lower room (room)
76 Base valve body (valve body)
85 Inner seat part 86 Outer seat part 93 Communication hole 107 Disc valve 122 Inner annular part 123 Outer annular part 124 Support part 133 Valve chamber

Claims (1)

A valve body in which a communication hole communicating between the two chambers is formed, and an inner seat part is formed on the center side and an outer seat part is formed on the outer peripheral side across the communication hole;
In a shock absorber provided with an annular disc valve that is radially movable with respect to the valve body and is arranged to be detachable from the inner seat portion and the outer seat portion,
The disc valve includes an outer annular portion that forms a valve chamber by the inner seat portion and the outer seat portion, an inner annular portion that is clamped to the center side of the inner seat portion, the outer annular portion, and the inner annular portion. It consists of two support parts that connect the annular part,
The two support portions are arranged on the same side from the center in the radial direction of the disc valve, and two outer connection portions arranged at intervals in the circumferential direction of the disc valve are the outer annular portions. In the radial direction of the disc valve, two inner connection portions arranged at intervals in the circumferential direction of the disc valve on the same opposite side as the center are connected to the inner annular portion, Two connecting arm portions are provided so as to connect the outer connecting portion and the inner connecting portion close to the circumferential direction of the disc valve, and the interval between the two inner connecting portions is set at two locations. A shock absorber characterized by being wider than the interval between the outer connecting portions .

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