Abstract: A suspension apparatus includes a valve device provided between an upper chamber and a lower chamber of each of hydraulic cylinders and configured to establish and block communication between these chambers. The valve device includes a first passage and an extension-side damping force generation mechanism. Hydraulic oil flows out from the upper chamber into the first passage due to a movement of a piston in a cylinder of each of the hydraulic cylinders. The extension-side damping force generation mechanism includes a damping valve and a back-pressure chamber. The damping valve is disposed in the first passage, and generates a damping force by restricting a flow of the hydraulic oil generated due to a sliding movement of the piston. The back-pressure chamber applies an inner pressure thereof to this damping valve in a valve-closing direction.

Abstract: A shock absorber that includes a damping force generation mechanism including a damping valve provided in a first passage through which a working fluid flows out due to a movement of a piston and a back-pressure chamber applying an internal pressure to the damping valve in a valve closing direction; and a back-pressure chamber inflow passage introducing the working fluid from the first passage into the back-pressure chamber is provided. The damping valve has: a first valve that opens and closes an opening of the first passage of the piston and comes into contact with the piston; a second valve provided on a valve opening side of the first valve and having a diameter smaller than the first valve, and defines the back-pressure chamber such that a pilot valve that slidably and tightly fits a seal member having an outer circumferential portion into a cylindrical part of a pilot case.

Abstract: A shock absorber includes a cylinder sealed with a working oil liquid, a piston slidably fitted in the cylinder, a piston rod connected to the piston and extended to the outside of the cylinder, and a plurality of passages through which the working oil liquid flows due to the sliding of pistons therein, and a damping force generating mechanism that is provided in a part of the passages and suppresses the flow of the working oil liquid to generate a damping force. The damping force generating mechanism includes a valve body through which the passage penetrates, an annular seat that projects from the valve body and surrounds the passage, and a disc that can be seated on the seat. A contact width at which the disc and the seat come into contact with each other is different depending on a position in the circumferential direction.

Abstract: Provided is a shock absorber that includes a middle chamber formed by a piston, a first damping-force generating device that is provided between an upper chamber and the middle chamber and generates a damping force, a second damping-force generating device that is provided between a lower chamber and the middle chamber and generates a damping force, and a position-based state changing device that changes a state of a passage to a state in which the upper chamber and the lower chamber communicate with each other, a state in which the upper chamber and the middle chamber communicate with each other, or a state in which the lower chamber and the middle chamber communicate with each other depending on a position of the piston.

Abstract: Provided is a shock absorber capable of smoothly changing a damping force in a low speed range of piston speed and of opening a main valve with a smaller differential pressure. An auxiliary valve (111) is provided on an upstream side of a main valve (27) in series with the main valve (27). Thus, the damping force in the low speed range of the piston speed can be smoothly changed. Further, the main valve (27) has a simply-supported structure in which an inner peripheral side thereof is prevented from being clamped and is supported in a cantilever state. Thus, the main valve (27) can be opened with a smaller differential pressure.

Abstract: A damper includes a cylinder in which a working fluid is enclosed, a piston which is slidably inserted into the cylinder, a piston rod which is connected with the piston, a disk valve which is provided to restrict a flow of a working fluid caused by sliding of the piston and to close an opening portion of a tubular case member, an annular seal portion which is provided on at least one surface side of the disk valve, and a chamber which is partitioned by the disk valve and the seal portion. Recessed portions and projecting portions are alternately formed in the disk valve.

Abstract: A shock absorber including: a first passage (101) allowing working fluid to flow out from one chamber (19) as a result of movement of a piston (18); a second passage (181) provided in parallel with the first passage; a damping force generating mechanism (41) provided in the first passage, and configured to generate a damping force; a tubular case member (140) including at least a part of the second passage formed therein; an annular disc (134) supported on an inner peripheral side or an outer peripheral side in the case member. An annular seal member (156) configured to seal a gap to the case member is provided on a non-supported side of the annular disc. The shock absorber further includes two chambers (171, 172) in the case member, which are defined and provided by the disc. The disc is configured to block flow to the second passage.

Abstract: [Problem] The present invention provides a damping force adjustable shock absorber capable of reducing manufacturing cost. [Means for Solving] A shock absorber 1 is configured in such a manner that a main valve 32 is disposed below a piston valve 5, and a sub valve 68 for variably adjusting a set load of the main valve 32 is provided in a piston case 21 above the piston valve 5, with a first valve body 53 of the sub valve 68 slidably sealed to a case member 60 by a metal seal at only one portion. Due to the configuration, the shock absorber 1 can ease precision of components of the sub valve 68, thereby reducing the manufacturing cost.

Abstract: A damper includes a first passage and a second passage in parallel, a first damping force generation mechanism of the first passage, a case member in which a portion of the second passage is formed, an annular disc disposed to face a bottom part in the case member to be able to be bent by a working fluid in the case member, a first chamber communicating with a first cylinder chamber and a second chamber communicating with a second cylinder chamber which are provided by the disc partitioning the inside of the case member, a first through hole provided in the bottom part of the case member to communicate with the second chamber, a bypass passage provided in parallel to the first through hole and configured to allow communication between the first chamber and the second cylinder chamber, and a second damping force generation mechanism provided in the bypass passage.

Abstract: A shock absorber that includes a damping force generation mechanism including a damping valve provided in a first passage through which a working fluid flows out due to a movement of a piston and a back-pressure chamber applying an internal pressure to the damping valve in a valve closing direction; and a back-pressure chamber inflow passage introducing the working fluid from the first passage into the back-pressure chamber is provided. The damping valve has: a first valve that opens and closes an opening of the first passage of the piston and comes into contact with the piston; a second valve provided on a valve opening side of the first valve and having a diameter smaller than the first valve, and defines the back-pressure chamber such that a pilot valve that slidably and tightly fits a seal member having an outer circumferential portion into a cylindrical part of a pilot case.

Abstract: Provided are a damper configured such that the axial play between a coil case and a case member can be eliminated without increasing a size of a solenoid, and a method of assembling the damper. An O-ring (seal member) is elastically supported by a tapered hole formed in an inner peripheral surface of a case member and a tapered shaft formed in an outer peripheral surface of a coil case, and a retaining ring is configured to receive an axial force generated by the O-ring. The configuration enables the play between the coil case and the case member of the solenoid to be eliminated. A damping force regulation mechanism, and in turn the damper, may be made more compact in comparison with a case in which the O-ring is received by the opening side end face of the case member.

Abstract: A suspension system, which is used together with a vehicle including a vehicle body, a front wheel, and a rear wheel, includes a mechanical damping force variable shock absorber disposed between the vehicle body and the front wheel and configured to mechanically change a damping force, and a damping force adjustable shock absorber disposed between the vehicle body and the rear wheel and configured to adjust a damping force by an actuator.

Abstract: A shock absorber includes a bottomed cylindrical housing (131), a disk (134) provided movably relative to the housing and forming a housing inner chamber (171) between a bottom portion of the housing and the disk, and a facing member (139) provided on an opposite side of the disk from the bottom portion so as to face the disk. Inner periphery sides of the housing and the facing member are fastened with a piston rod (21)inserted therethrough. A protruding portion is formed on the bottom portion of the housing or the facing member. The protruding portion protrudes toward the disk and is configured to restrict movement of the disk. A seal portion (158) is provided on one side of the disk where the protruding portion is provided. The seal portion is configured to seal between an outer periphery of the disk and an inner periphery of the housing.

Abstract: A shock absorber includes a bottomed cylindrical housing (131), a disk (134) provided movably relative to the housing and forming a housing inner chamber (171) between a bottom portion of the housing and the disk, and a facing member (139) provided on an opposite side of the disk from the bottom portion so as to face the disk. Inner periphery sides of the housing and the facing member are fastened with a piston rod (21)inserted therethrough. A protruding portion is formed on the bottom portion of the housing or the facing member. The protruding portion protrudes toward the disk and is configured to restrict movement of the disk. A seal portion (158) is provided on one side of the disk where the protruding portion is provided. The seal portion is configured to seal between an outer periphery of the disk and an inner periphery of the housing.

Abstract: Provided is a shock absorber capable of smoothly changing a damping force in a low speed range of piston speed and of opening a main valve with a smaller differential pressure. An auxiliary valve (111) is provided on an upstream side of a main valve (27) in series with the main valve (27). Thus, the damping force in the low speed range of the piston speed can be smoothly changed. Further, the main valve (27) has a simply-supported structure in which an inner peripheral side thereof is prevented from being clamped and is supported in a cantilever state. Thus, the main valve (27) can be opened with a smaller differential pressure.

Abstract: A shock absorber including: a first passage (101) allowing working fluid to flow out from one chamber (19) as a result of movement of a piston (18); a second passage (181) provided in parallel with the first passage; a damping force generating mechanism (41) provided in the first passage, and configured to generate a damping force; a tubular case member (140) including at least a part of the second passage formed therein; an annular disc (134) supported on an inner peripheral side or an outer peripheral side in the case member. An annular seal member (156) configured to seal a gap to the case member is provided on a non-supported side of the annular disc. The shock absorber further includes two chambers (171, 172) in the case member, which are defined and provided by the disc. The disc is configured to block flow to the second passage.

Abstract: A minimum length-side property in which an extension-side damping coefficient signifies a hard state in a range (Aa0) where the piston rod enters further inside the cylinder than a minimum length-side predetermined position (Sa1), and a maximum length-side property in which the extension-side damping coefficient signifies a soft state in a range (Aa4) where the piston rod extends further outside the cylinder than a maximum length-side predetermined position (Sa4) are included. An extension-side damping force property between the minimum length-side predetermined position (Sa1) and the maximum length-side predetermined position (Sa4) includes a part (Sa1 to Sa2, Sa3 to Sa4) in which a damping coefficient change rate with respect to a stroke of the piston rod is large and a part (Sa2 to Sa3) in which the damping coefficient change rate is small.

Abstract: Provided are a damper configured such that the axial play between a coil case and a case member can be eliminated without increasing a size of a solenoid, and a method of assembling the damper. An O-ring (seal member) is elastically supported by a tapered hole formed in an inner peripheral surface of a case member and a tapered shah formed in an outer peripheral surface of a coil case, and a retaining ring is configured to receive an axial force generated by the O-ring. The configuration enables the play between the coil case and the case member of the solenoid to be eliminated. A damping force regulation mechanism, and in turn the damper, may be made more compact in comparison with a case in which the O-ring is received by the opening side end face of the case member.

Abstract: A shock absorber includes: a damping valve that suppresses a flow of operating fluid due to the sliding of a piston to generate damping force; a bottomed tubular pilot case that forms a pilot chamber that causes pressure to act on the damping valve in a valve closing direction, together with the damping valve; and an annular seal member (146) that is provided to be fixed to the outer circumferential side of a rear surface of the damping valve, and is fitted into a tube of the pilot case so as to be slidable and to be in a liquid tight manner. A part of the flow of the operating fluid is guided to the pilot chamber and opening of the damping valve is suppressed by the pressure of the pilot chamber. An annular concave portion (380) is formed on the outer circumferential side of the seal member (146), and an annular convex portion (385) is formed on the inner circumferential side of the seal member (146).

Abstract: PROBLEM Provided is a damping force control type shock absorber capable of obtaining an appropriate damping force even in the event of a failure independently of the stoke of a valving element of a solenoid valve. MEANS FOR SOLVING A piston 5 having a piston rod 6 connected thereto is fitted in a cylinder 2 having hydraulic oil sealed therein, and a flow of hydraulic oil induced by movement of the piston 5 is controlled by a damping force generating mechanism 26 to generate a damping force. In the damping force generating mechanism 26, damping force is generated by a pilot-type main valve 27 and a normally-open pilot valve 28 which is a solenoid valve, and the damping force is adjusted by energization of a coil 37. A fail-safe valve 100 is provided downstream of the pilot valve 28. During normal operations, the fail-safe valve 100 opens the flow path through excitation of the coil 37 of the pilot valve 28.