JP2014196774A - Attenuation force adjustment type buffer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a cover to be positively fixed to a housing through a simple work and increase a fixing strength of the cover against the housing.SOLUTION: A cover 22 for covering an attenuation force adjustment mechanism 20 arranged in a housing 17 is provided with a pair of supporting segments 25 fitted to an outer surface of a storing cylinder 18 of the housing 17, a part of each of the supporting segments 25 in a peripheral direction is applied as an opening 25E along an axial direction. The opening 25E is positioned at the extremity end of each of the supporting segments 25 to have openings 25E1, 25E2. In turn, the cover 22 is constructed such that it is provided with a connecting member 26 striding over both ends of openings 25E1, 25E2, extending in a peripheral direction to connect both ends of the openings 25E1, 25E2. Accordingly, the cover 22 can protect the attenuation force adjustment mechanism 20 while covering and hiding it against flying stones running and the like. In turn, the cover 22 and the connecting member 26 can be fixed without using any bolts and the like.

Description

  The present invention relates to a damping force adjusting type shock absorber that is suitably used for buffering vibrations of, for example, an automobile.

  A vehicle such as a four-wheeled vehicle is provided with a damping force adjustment type shock absorber between the relatively moving wheel side and the vehicle body side, and is configured to buffer upward and downward vibrations and the like generated during traveling. . The damping force adjusting shock absorber includes a cylinder in which a working fluid is sealed, a piston inserted into the cylinder, a piston rod connected to the piston and extending outside the cylinder, And a damping force adjusting mechanism provided in a housing extended to the outside.

  Here, the damping force adjustment type shock absorber has a protective cover attached to the housing in order to protect the damping force adjustment mechanism provided in the housing. The protective cover is formed of an elastic material such as rubber or plastic, and is configured to be attached to the housing using the elastic force (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 58-102852

  By the way, the protective cover by patent document 1 mentioned above is set as the structure attached to a housing using an elastic force. In this case, the elastic force of rubber, plastic, or the like may decrease due to aging or creep phenomenon, and the protective cover may fall off.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a damping that enables the cover to be securely attached to the housing with a simple operation and to improve the attachment strength of the cover to the housing. The object is to provide a force adjustable shock absorber.

  In order to solve the above-described problems, the present invention provides a damping force adjusting type shock absorber attached between two members that can move relative to each other, and includes a cylinder in which a working fluid is sealed, and a piston inserted in the cylinder. A piston rod connected to the piston and extending to the outside of the cylinder; and a damping force adjusting mechanism provided in the housing extending to the outside of the cylinder, and fitted to the outer surface of the housing. And a cover that is an opening in which a part in the circumferential direction of the support is opened in the axial direction, and extends in the circumferential direction across both ends of the opening of the cover. And a coupling member that couples both ends of the opening.

  With the above configuration, the cover can be reliably attached to the housing by simple work, and the attachment strength of the cover to the housing can be improved.

It is sectional drawing which shows the damping force adjustment type hydraulic shock absorber by embodiment of this invention. It is a front view which expands and shows the cylinder, housing, cover, coupling member, etc. in FIG. It is sectional drawing which looked at the cylinder, the housing, the cover, and the coupling member from the direction of arrows III-III in FIG. It is sectional drawing which looked at the housing, the damping-force adjustment mechanism, the cover, and the coupling member from the arrow IV-IV direction in FIG. It is sectional drawing which looked at the housing, the damping-force adjustment mechanism, the cover, and the coupling member from the arrow VV direction in FIG. It is the expanded sectional view which looked at the housing, the cover, and the coupling member from the arrow VI-VI direction in FIG. It is the expanded sectional view which looked at the cover from which the support part became the free state from the same position as FIG. It is a perspective view shown in the state where the housing, the cover, the coupling member and the like are rotated 90 degrees and the opening is disposed on the lower side. FIG. 9 is an exploded perspective view showing the housing, the cover, and the coupling member in FIG. 8 in a separated state.

  Hereinafter, a case where the damping force adjustment type shock absorber according to the embodiment of the present invention is applied to a damping force adjustment type hydraulic shock absorber for a vehicle will be described as an example, and will be described in detail with reference to FIGS.

  In FIG. 1, a bottomed cylindrical outer cylinder 2 as a cylinder forming an outer shell of a damping force adjustment type hydraulic shock absorber 1 (hereinafter referred to as a hydraulic shock absorber 1) is fixed at the lower end side by using welding means or the like. Closed by the bottom cap 3, the upper end side is a caulking portion 2A bent radially inward. Between the caulking portion 2 </ b> A and the inner cylinder 4, a rod guide 9 and a seal member 10 described later are provided. On the other hand, an opening 2B is formed on the lower side of the outer cylinder 2 at a position concentric with a connection port 12C of the intermediate cylinder 12 described later, and a damping force adjusting mechanism 20 described later is accommodated at a position corresponding to the opening 2B. A housing 17 is attached. Further, the bottom cap 3 is provided with an attachment eye 3A that is attached to, for example, a vehicle wheel.

  In the outer cylinder 2, an inner cylinder 4 serving as a cylinder is provided on the same axis as the outer cylinder 2. The inner cylinder 4 is attached with a lower end side fitted to a bottom valve 13 described later, and an upper end side fitted with a rod guide 9. An oil liquid as a working fluid is sealed in the inner cylinder 4. The working fluid is not limited to oil and oil, but may be water mixed with an additive, for example.

  An annular reservoir chamber A is formed between the inner cylinder 4 and the outer cylinder 2, and a gas is sealed in the reservoir chamber A together with the oil liquid. This gas may be atmospheric pressure air or a compressed gas such as nitrogen gas. An oil hole 4 </ b> A that allows the rod-side oil chamber B to always communicate with the annular oil chamber D is formed in the radial direction at an intermediate position in the length direction (upward and downward) of the inner cylinder 4.

  The piston 5 is slidably inserted into the inner cylinder 4. The piston 5 defines the inside of the inner cylinder 4 into a rod side oil chamber B and a bottom side oil chamber C. The piston 5 is formed with a plurality of oil passages 5A and 5B that allow the rod-side oil chamber B and the bottom-side oil chamber C to communicate with each other in the circumferential direction.

  Here, an extension-side disc valve 6 is provided on the lower end surface of the piston 5. The extension-side disc valve 6 opens when the pressure in the rod-side oil chamber B exceeds the relief set pressure when the piston 5 slides upward in the extension stroke of the piston rod 8. The pressure is relieved to the bottom side oil chamber C via each oil passage 5A. This relief set pressure is set to a pressure higher than the valve opening pressure when the damping force adjusting mechanism 20 described later is set to hardware.

  On the upper end surface of the piston 5, there is provided a check valve 7 on the contraction side that opens when the piston 5 is slid downward in the contraction process of the piston rod 8 and closes at other times. This check valve 7 allows the oil in the bottom side oil chamber C to flow in each oil passage 5B toward the rod side oil chamber B, and prevents the oil from flowing in the opposite direction. To do. The valve opening pressure of the check valve 7 is set to a pressure lower than the valve opening pressure when the damping force adjusting mechanism 20 is set to be soft, and substantially no damping force is generated. The valve opening pressure that does not substantially generate a damping force is a force less than the friction of the piston 5 and the seal member 10 and does not affect the movement of the vehicle.

  The piston rod 8 extending in the axial direction in the inner cylinder 4 is inserted into the inner cylinder 4 at the lower end side and attached to the piston 5 by a nut 8A or the like. Further, the upper end side of the piston rod 8 extends to the outside of the outer cylinder 2 and the inner cylinder 4 via the rod guide 9. The lower end of the piston rod 8 may be further extended so as to extend outward from the bottom portion (for example, the bottom cap 3) side, so that a so-called double rod may be configured.

  A stepped cylindrical rod guide 9 is provided on the upper end side of the inner cylinder 4. The rod guide 9 positions the upper part of the inner cylinder 4 concentrically with the outer cylinder 2 and guides the piston rod 8 to be slidable in the axial direction on the inner peripheral side thereof. An annular seal member 10 is provided between the rod guide 9 and the caulking portion 2A of the outer cylinder 2.

  The seal member 10 is formed by baking an elastic material such as rubber on a metal annular plate provided with a hole through which the piston rod 8 is inserted at the center, and the inner circumference is in sliding contact with the outer circumference side of the piston rod 8. The space between the piston rod 8 is sealed. The seal member 10 is formed with a lip seal 10A as a check valve that extends so as to contact the rod guide 9 on the lower surface side. The lip seal 10A is disposed between the oil sump chamber 11 and the reservoir chamber A, and the oil in the sump chamber 11 circulates toward the reservoir chamber A via the return passage 9A of the rod guide 9. To prevent the reverse flow.

  An intermediate cylinder 12 is disposed between the outer cylinder 2 and the inner cylinder 4. The intermediate cylinder 12 is attached to the outer peripheral side of the inner cylinder 4 via upper and lower seal rings 12A and 12B, for example. The intermediate cylinder 12 forms therein an annular oil chamber D extending so as to surround the outer peripheral side of the inner cylinder 4 over the entire circumference, and this annular oil chamber D is an oil chamber independent of the reservoir chamber A. ing. The annular oil chamber D is always in communication with the rod-side oil chamber B through a radial oil hole 4 </ b> A formed in the inner cylinder 4. On the other hand, a connection port 12C to which a cylindrical holder 20E of a damping force adjusting mechanism 20 to be described later is attached is provided on the lower end side of the intermediate cylinder 12.

  The bottom valve 13 is located on the lower end side of the inner cylinder 4 and is provided between the bottom cap 3 and the inner cylinder 4. The bottom valve 13 includes a valve body 14 that defines a reservoir chamber A and a bottom oil chamber C between the bottom cap 3 and the inner cylinder 4, and a reduction-side disk valve provided on the lower surface side of the valve body 14. 15, and an extension-side check valve 16 provided on the upper surface side of the valve body 14. In the valve body 14, oil passages 14 </ b> A and 14 </ b> B that allow the reservoir chamber A and the bottom oil chamber C to communicate with each other are formed at intervals in the circumferential direction.

  The disk valve 15 on the reduction side opens when the pressure in the bottom side oil chamber C exceeds the relief set pressure when the piston 5 slides downward in the reduction stroke of the piston rod 8, The pressure in the side oil chamber C is relieved to the reservoir chamber A side through each oil passage 14A. This relief set pressure is set to a pressure higher than the valve opening pressure when the damping force adjusting mechanism 20 is set to hardware.

  The extension-side check valve 16 opens when the piston 5 slides upward in the extension stroke of the piston rod 8, and closes at other times. This check valve 16 allows the oil in the reservoir chamber A to flow through each oil passage 14B toward the bottom oil chamber C, and prevents the oil from flowing in the opposite direction. It is. The valve opening pressure of the check valve 16 is set to a pressure lower than the valve opening pressure when the damping force adjusting mechanism 20 is set to soft, and the damping force is substantially reduced in the same manner as the check valve 7 described above. Does not occur.

  The housing 17 is located on the lower side of the outer cylinder 2 and extends outside the outer cylinder 2. As shown in FIGS. 2, 3, 4, etc., the housing 17 accommodates a part of the damping force adjusting mechanism 20, and includes a housing cylinder 18 and a lock nut 19. The housing cylinder 18 is formed as a cylindrical body having a diameter dimension d <b> 1 centering on a position O <b> 1 of the central axis that is the center position of the housing 17. The proximal end side of the housing cylinder 18 is fixed around the opening 2 </ b> B of the outer cylinder 2, and the distal end side protrudes outward in the radial direction from the outer cylinder 2. As shown in FIG. 4, a male screw portion 18 </ b> A that engages with the female screw portion 19 </ b> C of the lock nut 19 is formed on the distal end side of the housing cylinder 18. In addition, as long as the storage cylinder 18 is cylindrical, other shapes, such as a polygon, may be sufficient.

  On the other hand, the lock nut 19 is formed as a cylindrical body having a diameter dimension d2, and has a thick part 19A having an inner diameter dimension substantially equal to the inner diameter dimension of the accommodating cylinder 18, and an inner diameter dimension of the thick part 19A. The thin portion 19B has a large inner diameter. On the inner peripheral side of the thin wall portion 19B, a female screw portion 19C that is screwed into the male screw portion 18A of the housing cylinder 18 is formed. A ring presser 19D is formed on the inner peripheral side of the thick wall portion 19A by expanding the diameter of the boundary portion with the thin wall portion 19B. The ring presser 19D is for pressing a ring member 21 (described later) attached to the damping force adjusting mechanism 20.

  When the damping force adjusting mechanism 20 is attached to the housing 17, the main body portion 20A of the damping force adjusting mechanism 20 is inserted into the lock nut 19, and the ring member 21 attached to the outer periphery of the main body portion 20A is attached to the ring presser 19D. Engage. In this state, the female thread portion 19C of the lock nut 19 is screwed to the threaded portion 18A of the housing cylinder 18 while the main body portion 20A of the damping force adjusting mechanism 20 is inserted into the housing tube 18.

  Thus, in the housing 17, the position of the lock nut 19 on the distal end side becomes a large diameter portion having a diameter dimension D2, and the position of the housing cylinder 18 between the lock nut 19 and the outer cylinder 2 becomes a small diameter portion having a diameter dimension D1. It is formed as a cut-off cylinder. The damping force adjusting mechanism 20 can be housed in a retaining state in the housing 17 formed as the cut cylindrical body. The lock nut may be eliminated and the main body of the damping force adjusting mechanism may be directly screwed, fitted, and caulked to the housing. In this case, an enlarged diameter portion may be provided on the outer periphery of the housing and formed as a cut cylindrical body.

  A part of the damping force adjusting mechanism 20 is provided in the housing 17, and the remaining part protrudes (exposes) from the housing 17. The damping force adjusting mechanism 20 generates a damping force by controlling the flow rate of the oil liquid flowing from the annular oil chamber D to the reservoir chamber A by a damping force adjusting valve (not shown). The damping force adjusting mechanism 20 adjusts the valve opening pressure of the damping force adjusting valve by an actuator (not shown) composed of a direct acting solenoid, a rotary stepping motor, or the like. Can be variably adjusted. That is, the damping force adjusting mechanism 20 can adjust the damping force stepwise or steplessly between a soft setting damping force with a soft ride and a hard setting damping force with a hard ride.

  The damping force adjustment mechanism 20 has a substantially cylindrical main body portion 20A, and includes a damping force adjustment valve, an actuator, and the like in a state of being housed inside the main body portion 20A or being connected to the outside. In other words, the main body portion 20A includes a damping force adjustment valve and an actuator. For example, the damping force adjustment valve is arranged in the housing 17 and the actuator is arranged so that a part of the actuator protrudes from the housing 17. Is done.

  The outer diameter of the main body 20A is set to be slightly smaller than the inner diameter of the housing cylinder 18 and the inner diameter of the thick portion 19A of the lock nut 19. A semicircular ring groove 20B is formed on the outer peripheral side of the main body 20A in the middle of the axial direction, and a ring member 21 is attached to the ring groove 20B in an engaged state.

  On the other hand, the cable body 20C is provided on the main body 20A so as to protrude outward in the radial direction from the end opposite to the insertion direction. The cable extraction portion 20 </ b> C constitutes an L-shaped guide for extracting the cable 20 </ b> D for controlling the actuator to the outside along the housing 17.

  Further, the damping force adjusting mechanism 20 is provided with a cylindrical holder 20E (shown in FIG. 1) extending from the damping force adjusting valve toward the intermediate cylinder 12. The cylindrical holder 20 </ b> E has a proximal end connected to the connection port 12 </ b> C of the intermediate cylinder 12, and a distal end connected to a damping force adjusting valve in the housing 17. Thereby, the cylindrical holder 20E comprises the oil path which distribute | circulates an oil liquid between the cyclic | annular oil chamber D and the damping force adjustment valve.

  The ring member 21 is formed in a ring shape from, for example, an elastic resin material or rubber material, and is attached to the ring groove 20B of the damping force adjusting mechanism 20 in an engaged state. The ring member 21 is engaged with both the ring presser 19D of the lock nut 19 and the ring groove 20B of the damping force adjusting mechanism 20, thereby holding the damping force adjusting mechanism 20 in a retaining state with respect to the housing 17. be able to.

  Next, the configuration of the cover 22 and the coupling member 26 attached to the housing 17 in order to protect the damping force adjusting mechanism 20 will be described.

  The cover 22 protects the damping force adjusting mechanism 20 and can cover the lock nut 19 that is a part of the outer periphery of the housing 17 and the exposed portion of the damping force adjusting mechanism 20 that protrudes from the housing 17. The cover 22 is made of, for example, an elastic resin material, and includes a cover body 23, a bulging portion 24, and a support portion 25 as shown in FIGS.

  As shown in FIG. 9 and the like, the cover main body 23 constituting the cover 22 extends in the axial direction with a U-shape that is partially open in the circumferential direction. In this case, the cover main body 23 opens in the horizontal direction with the cover 22 attached to the housing 17. The base end side that is the attachment side of the cover body 23 is a large peripheral wall 23A that surrounds the lock nut 19, and the distal end side is a small peripheral wall 23B that surrounds the main body portion 20A of the damping force adjusting mechanism 20 than the large peripheral wall 23A. The tip of the small peripheral wall 23B is closed by a lid 23C. Thereby, the cover body 23 has a part in the circumferential direction as the mounting opening 23D, and the part of the lock nut 19 and the exposed part of the main body part 20A of the damping force adjusting mechanism 20 are accommodated therein through the mounting opening 23D. Can do.

  The bulging portion 24 covers the cable extraction portion 20 </ b> C of the damping force adjustment mechanism 20, and is provided on the side opposite to the attachment opening 23 </ b> D of the cover body 23. The bulging portion 24 extends in the axial direction with a U-shape that is open on the cover body 23 side, and its proximal end protrudes from the cover body 23. Specifically, the bulging portion 24 faces with a larger interval dimension than the cable extraction portion 20C of the damping force adjusting mechanism 20, and the left and right side surface portions 24A attached to the cover body 23, the cover body 23, A semi-cylindrical arc portion 24B that is positioned on the opposite side and covers between the side portions 24A, and a lid portion 24C that covers the side portions 24A and the tip side of the arc portion 24B. Thereby, the bulging portion 24 is opened on the protruding end 24D side, and a support portion 25 described later is provided on each side surface portion 24A on the protruding end 24D side.

  The support portion 25 is provided so as to be fitted to the outer surface of the housing 17 when the cover 22 is attached to the housing 17. The support portion 25 has a part in the circumferential direction that opens in the axial direction, and is disposed so as to face the position O 1 of the central axis of the housing cylinder 18 that constitutes the housing 17. The pair of support portions 25 facing each other hold the housing cylinder 18 with a biasing force at all times.

  Each support portion 25 is formed as an arc-shaped plate body, and one end in the length direction thereof is attached to the protruding end 24 </ b> D of the bulging portion 24. As for each support part 25, inner surface 25A which mutually faces is in contact with the outer peripheral surface of the accommodating cylinder 18. On the other hand, each rib 25C is provided on the outer surface 25B of each support portion 25 over the entire length so as to sandwich the outer surface 25B. By providing each rib 25C, the support portion 25 can ensure a sufficient elastic force (biasing force) without increasing the plate thickness dimension, and can realize weight reduction and cost reduction.

  At the intermediate position in the length direction of each support portion 25, there are provided locking portions 25D for locking both ends of the coupling member 26 with respect to the cover 22, that is, locking claws 26E of the coupling member 26 described later. Yes. The locking portion 25D is formed in a gate shape that forms a rectangular frame in cooperation with the outer surface 25B and the ribs 25C, and the engagement claw portion 26E is engaged with the gate shape portion.

  As shown in FIG. 7, an opening 25 </ b> E is provided in a part in the circumferential direction of each support portion 25, specifically, in the axial direction at a position opposite to the bulging portion 24 in the radial direction. The opening 25E has an opening interval dimension W1 between the one side opening 25E1 and the other side opening 25E2. The opening interval dimension W1 of the openings 25E is smaller than the diameter dimension D1 of the housing cylinder 18 when each support part 25 is in a free state. The dimensions can be set.

  Here, the shape set so that each support part 25 always holds the accommodating cylinder 18 of the housing 17 with a biasing force will be described with reference to FIG.

  The shape of the inner surface 25A in the free state of each support portion 25 is formed in a circular shape with a radial dimension r or an elliptical shape close to a circular shape. The radius dimension r is larger than the radius dimension D1 / 2 based on the diameter dimension D1 of the housing cylinder 18 (r> D1 / 2). In this case, the radial dimension r of the inner surface 25A is set larger than the radial dimension D1 / 2 of the housing cylinder 18 in a range of, for example, 1 to 10%, preferably 2 to 6%.

  Further, the center position O2 (center position of the cover 22) of the inner surface 25A of each support portion 25 and the center axis position O1 (center position of the housing) of the housing cylinder 18 are arranged at different positions. Specifically, the center position O2 of the inner surface 25A of each support portion 25 is disposed in an offset state at a position that exceeds the center axis position O1 of the housing cylinder 18 by the length dimension L on the opposite side of the support portion 25. . The offset dimension L is set so that the interval dimension W2 at the position of the deepest portion 25F of each support portion 25 is smaller than the diameter dimension D1 of the housing cylinder 18.

  Thereby, as shown in FIG. 6, each support portion 25 can always hold the housing cylinder 18 of the housing 17 with an urging force, and the peripheral position of the deepest portion 25 </ b> F is brought into contact with the housing cylinder 18. Thus, the storage cylinder 18 can be sandwiched deeply. In the state where the holding cylinder 18 is sandwiched between the support portions 25, the support portions 25 are engaged with the lock nuts 19, so that the cover 22 can be attached to the housing 17 in a retaining state. .

  The coupling member 26 extends in the circumferential direction across both ends of the openings 25E1 and 25E2 of the opening 25E provided between the support portions 25 of the cover 22, thereby coupling both ends of the openings 25E1 and 25E2. Is. The coupling member 26 is a member (cover holding member) that closes the opening 25E side of each support portion 25 and holds it in a fixed state so that the support portions 25 of the cover 22 attached to the housing 17 do not come off. is there. The coupling member 26 is formed in a U shape by appropriately bending a belt-like body made of an elastic metal material at a plurality of locations in the length direction. In this case, the width dimension of the coupling member 26 is set to be smaller than the width dimension of the outer surface 25B of the support portion 25 (the inner width dimension of the locking portion 25D).

  The coupling member 26 includes a central plate portion 26A that covers the opening 25E between the support portions 25, and a U-shaped gripping portion 26B that protrudes left and right from both sides in the length direction of the central plate portion 26A. An arm plate portion 26C extending straight from each gripping portion 26B so as to pass through the locking portion 25D of each support portion 25, and a turn-back portion 26D formed by turning the tip end portion of each arm plate portion 26C outward. And an engaging claw portion 26E formed by bending the tip of each folded portion 26D into a crank shape.

  Here, when the folded portion 26D is a single product that is not attached to the cover 22, the tip end side is the insertion height dimension of the locking portion 25D of the support portion 25 (inside the locking portion 25D that is the radial direction of the support portion 25). It is wider than (width dimension). Thereby, when the arm plate part 26C and the folded part 26D are inserted deeply into the locking part 25D, the engaging claw part 26E is locked to the locking part 25D by the spring force of the folded part 26D.

  A case where the coupling member 26 is attached to each support portion 25 of the cover 22 will be described. When the cover 22 is assembled to the housing 17, as shown by a two-dot chain line in FIG. 6, each arm plate portion 26C and the folded portion 26D are respectively supported by the gripping portions 26B of the coupling member 26 between the fingertips. It is inserted deeply into the 25 locking portions 25D. When these are inserted to a position where the locking portion 25D exceeds the locking portion 25D, the engagement claw portion 26E is automatically engaged with the locking portion 25D by the spring force of the folded portion 26D, as shown by the solid line in FIG. Can be stopped. In this case, since the spring force of the folded portion 26D always acts on the engagement claw portion 26E in the direction in which the engagement state is maintained, the engagement claw portion 26E is surely prevented from being detached from the engagement portion 25D. Can be engaged.

  Thus, in the state where the coupling member 26 is attached to each support portion 25 of the cover 22, the central plate portion 26 </ b> A can cover the opening 25 </ b> E between the support portions 25, so that the cover 22 does not fall off the housing 17. Can be securely installed. Moreover, the coupling member 26 can prevent rattling of the cover 22 due to vibration by pressing the central plate portion 26 </ b> A against the housing cylinder 18.

  On the other hand, when the coupling member 26 is removed from the support portions 25 of the cover 22, the folded portions 26 </ b> D are crushed to a size that passes through the locking portions 25 </ b> D of the support portions 25 against the spring force. In this state, it is possible to remove the coupling member 26 from the support portions 25 of the cover 22 by pinching each gripping portion 26 </ b> B of the coupling member 26 with a fingertip.

  The hydraulic shock absorber 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, when mounting the hydraulic shock absorber 1 on a vehicle such as an automobile, for example, the upper end side of the piston rod 8 is attached to the vehicle body side of the vehicle, and the attachment eye 3A side provided on the bottom cap 3 is attached to the wheel side. The cable 20D of the damping force adjusting mechanism 20 is connected to a vehicle controller (not shown) or the like.

  When the vehicle is running, if upward or downward vibration is generated due to road surface unevenness or the like, the piston rod 8 is displaced so as to extend or contract from the outer cylinder 2, and a damping force is generated by the damping force adjusting mechanism 20 or the like. The vibration of the vehicle can be buffered. At this time, the damping force generated by the hydraulic shock absorber 1 can be variably adjusted by controlling the damping force adjusting mechanism 20 by the controller.

  Next, working operations when the cover 22 and the coupling member 26 are attached to the housing 17 will be described.

  First, when the cover 22 is attached to the housing 17, as shown in FIG. 9, the cover 22 is made to approach the housing tube 18 of the housing 17 from the cable extraction portion 20 </ b> C side of the damping force adjusting mechanism 20. By pressing the support portions 25 against the outer surface of the housing cylinder 18 as they are, the openings 25E of the support portions 25 can be opened, and the support portions 25 can be fitted and provided on the outer surface of the housing cylinder 18. . In this state, each support portion 25 is clamped so as to deeply embrace the housing cylinder 18 at the deepest portion 25F of the inner surface 25A, so that the cover 22 can be firmly attached to the housing 17. Further, each support portion 25 is restricted from moving toward the distal end in the axial direction by the large-diameter lock nut 19, so that it does not move in the axial direction and fall off the housing 17.

  Further, when the cover 22 is attached to the housing 17, the coupling member 26 is made to approach in the radial direction from the opening 25 </ b> E side of each support portion 25 toward each support portion 25. At this time, the engaging claw 26E is locked to the locking portion 25D by deeply inserting the arm plate portions 26C and the folded portions 26D of the coupling member 26 into the locking portions 25D of the support portions 25. Can do. Thereby, the coupling member 26 can be reliably attached so that each support part 25 is not dropped on the outer surface of the housing cylinder 18.

  On the other hand, when removing the cover 22 from the housing 17, first, the coupling member 26 is removed from each support portion 25 of the cover 22. That is, each folded portion 26D of the coupling member 26 is crushed against a spring force, and in this state, the coupling member 26 is pulled from the support portion 25 of the cover 22 by pulling the coupling member 26 to the side opposite to the mounting direction. Can be removed. Next, when the coupling member 26 is removed from the cover 22, each cover 22 can be opened and the cover 22 can be removed from the housing 17 by pulling the cover 22 in the direction opposite to the mounting direction.

  Thus, according to the present embodiment, the cover 22 that covers the damping force adjusting mechanism 20 provided in the housing 17 is provided with a pair of support portions 25 that fit into the outer surface of the housing cylinder 18 of the housing 17. A part of the support portion 25 in the circumferential direction is an opening 25E extending in the axial direction, and the opening 25E has openings 25E1 and 25E2 located on the tip side of each support portion 25. On the other hand, the cover 22 is provided with a coupling member 26 that extends in the circumferential direction across both ends of the openings 25E1 and 25E2 and couples both ends of the openings 25E1 and 25E2.

  Therefore, the cover 22 can cover the damping force adjusting mechanism 20 and protect the damping force adjusting mechanism 20 from a flying stone or the like during traveling. Moreover, the cover 22 is fixed to the housing 17 only by locking the engaging claw 26E of the coupling member 26 to the locking portion 25D provided on the support portion 25 of the cover 22 without using a bolt or the like. Can be held in.

  As a result, the cover 22 can be securely attached to the housing 17 by a simple operation, so that the attachment strength of the cover 22 to the housing 17 can be increased. As a result, the cover 22 can be prevented from falling off, and the life and reliability of the damping force adjusting mechanism 20 can be improved.

  Moreover, since the cover 22 is formed using a resin material, a complicated shape can be easily obtained. Thereby, the cover 22 can efficiently cover the damping force adjusting mechanism 20 with a minimum gap, and can be reduced in size. On the other hand, since the coupling member 26 is formed using a metal material, it does not easily deteriorate over time and does not cause a creep phenomenon. Also in this respect, the cover 22 can be securely fixed to the housing 17.

  Further, since the coupling member 26 is formed using a metal material having elasticity, a state in which each engaging claw portion 26E exerts a biasing force (spring force) on the locking portion 25D of the support portion 25. It can be locked with. Therefore, each engaging claw part 26E can be stably engaged so as not to drop off by always pressing the engaging claw part 26E against the locking part 25D.

  On the other hand, the position O1 of the central axis of the housing cylinder 18 that is the center position of the housing 17 and the center position O2 of the inner surface 25A of the support portion 25 that is the center position of the cover 22 are arranged at different positions by the offset dimension L. It is said. Accordingly, each support portion 25 can always hold the housing cylinder 18 of the housing 17 with an urging force, and the housing cylinder 18 can be deepened by bringing the peripheral position of the deepest portion 25F into contact with the housing cylinder 18. Thus, the mounting strength can be increased.

  Furthermore, each support portion 25 of the cover 22 is provided with a locking portion 25D, and when the coupling member 26 is attached to the cover 22, the engagement claw portions 26E provided at both ends of the coupling member 26 are locked. It is set as the structure latched to the part 25D. Thereby, it can be made to engage reliably with respect to each support part 25 so that the coupling member 26 may not remove | deviate.

  In the embodiment, the case where the cover 22 is formed using a resin material has been described as an example. However, the present invention is not limited to this. For example, the cover 22 may be formed using a metal material. Moreover, as long as the purpose of protecting the housing 17 and the damping force adjusting mechanism 20 can be achieved, the shape may be any shape.

  In the embodiment, when the length direction of the outer cylinder 2 is a vertical direction, the cover 22 and the coupling member 26 are illustrated as being attached to and detached from the housing 17 in the horizontal direction. However, the present invention is not limited to this, and for example, the cover 22 and the coupling member 26 may be configured to be attached and detached in the same vertical direction as the length direction of the housing 17. In addition to this, it may be configured to be attached and detached in an oblique direction between the horizontal direction and the vertical direction.

  Furthermore, in the embodiment, the damping force adjustment type hydraulic shock absorber 1 as a damping force adjustment type shock absorber provided in a vehicle such as an automobile has been described as an example. However, the present invention is not limited to this. For example, the present invention can also be applied to a damping force adjustment type shock absorber used for various machines, buildings, and the like which are vibration sources.

  Next, the invention included in the above embodiment will be described. That is, in the present invention, the cover is formed using a resin material, and the coupling member is formed using a metal material. Therefore, the cover made of a resin material can easily obtain a complicated shape, can efficiently cover the damping force adjusting mechanism with a minimum gap, and can be downsized. On the other hand, since the coupling member is formed using a metal material, it does not easily deteriorate over time and does not cause a creep phenomenon.

  Further, according to the present invention, the center position of the cover and the center position of the housing are arranged at different positions. Thereby, when fitting the support part of a cover with a housing, it can always be made to fit with a biasing force.

  Furthermore, according to the present invention, the cover support portion is provided with a locking portion that locks both ends of the coupling member with respect to the cover. Thereby, it can be made to engage reliably so that a coupling member may not remove | deviate with respect to a support part.

1 Damping force adjustable hydraulic shock absorber 2 Outer cylinder (cylinder)
4 Inner cylinder (cylinder)
5 piston 8 piston rod 12 intermediate cylinder 17 housing 18 housing cylinder 19 lock nut 20 damping force adjusting mechanism 22 cover 23 cover body 24 bulging part 25 support part 25D locking part 25E opening 25E1 one side opening part 25E2 other side opening part 26 Coupling member 26E Engagement claw O1 Position of central axis of housing cylinder (center position of housing)
Center position of the inner surface of the O2 support (cover center position)
L Offset dimension

Claims (4)

A damping force adjustable shock absorber attached between two members capable of relative movement,
A cylinder filled with a working fluid;
A piston inserted into the cylinder;
A piston rod connected to the piston and extending outside the cylinder;
A damping force adjusting mechanism provided in a housing extended to the outside of the cylinder,
A cover having a support portion fitted to the outer surface of the housing, wherein a part of the support portion in the circumferential direction is an opening that extends in the axial direction;
A damping force adjusting type shock absorber comprising: a coupling member that extends in a circumferential direction across both ends of the opening of the cover and couples both ends of the opening.   The damping force adjustment type shock absorber according to claim 1, wherein the cover is formed using a resin material, and the coupling member is formed using a metal material.   The damping force adjusting type shock absorber according to claim 1 or 2, wherein the damper is arranged at a position different from a center position of the cover and a center position of the housing.   The damping force adjusting type shock absorber according to claim 1, 2 or 3, wherein the support portion of the cover is provided with a locking portion that locks both ends of the coupling member with respect to the cover.

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