Abstract: The present shock absorber has a pressure tube with a compression chamber and a traction chamber, separated by a piston provided with a traction passage. The valve includes: a counter pressure chamber loaded by piston, provided with an upper opening and a control base, open to the compression chamber, where a hollow sealing plug is displaceable between a closed position, hence communicating traction passage only with the counter pressure chamber, and open positions; a return spring driving sealing plug to its closed position; and an inertial seal, inside the counter pressure chamber and displaceable from inoperative position, away from the control base, to operative position, where it blocks said base, increasing hydraulic pressure in the counter pressure chamber to hydraulically drive sealing plug to its closed position when piston is subjected to a given upward acceleration.

Abstract: An air damper is provided which can exhibit an appropriate braking force in accordance with an input load. There is provided an air damper including: a tubular cylinder 1 in which both end portions are opened; a piston 2 which moves within the cylinder 1; and a cap 3 which closes a one-end opening of the cylinder 1, wherein the cylinder 1 has an annular seal surface 4 formed on a circumferential surface of the one-end opening, wherein the cap is mounted on the one-end opening side of the cylinder 1 so as to be moveable or deformable along an axial direction of the cylinder 1, wherein the cap is brought into contact with or separated from the seal surface 4 in accordance with a pressure change due to a movement of the piston 2 within the cylinder 1, and wherein a first orifice 14 is opened in a base plate 12 of the cap, characterized in that: a second orifice having an inlet area smaller than the first orifice is defined between the cap 3 and the cylinder 1 during an operation of the first orifice 14.

Abstract: A piston connected to a piston rod is fitted in a cylinder having a hydraulic oil sealed therein. Flows of hydraulic oil induced in extension and compression passages and by sliding movement of the piston are controlled by extension and compression damping force generating mechanisms, respectively, to generate damping force. In the extension and compression damping force generating mechanisms, the hydraulic oil is introduced into back pressure chambers through back pressure introducing passages, respectively, and the opening of relief valves is controlled by the pressures in the back pressure chambers, respectively. The inner peripheral portions of the relief valves are supported from their rear sides by support members to provide gaps on the front sides of the relief valves, respectively. When the relief valves open, their inner peripheral edge portions move within the gaps pivotally about the support members as fulcrums, respectively.

Abstract: A shock absorber has a compression valve assembly which functions during a compression stroke, a rebound valve assembly which functions during a rebound stroke and a velocity sensitive valve which is in series with one or both of the compression valve assembly and the rebound valve assembly. The compression valve assembly, the rebound valve assembly and the velocity sensitive valve can be incorporated into a piston assembly, a base valve assembly or both.

Abstract: A front fork for easily optimizing an oil quantity in a damper cylinder with a relatively simple structure without affecting operability of a free piston even in an assembled state. An escape portion is formed on an outer periphery of a piston rod at a position where a seal member mounted on a sealing cap faces in an opposed manner when a front fork extends to the maximum.

Abstract: A delay return gas spring including a piston at least partially received in a cylinder for reciprocation between extended and compressed positions over a cycle including a compression stroke and a return stroke. A seal disposed between the cylinder and the piston separates a primary chamber on one side of the seal from a secondary chamber on another side of the seal during a portion of the cycle. A passage communicates with the secondary chamber and with the primary chamber. The seal is relatively movable between an open position permitting free flow of gas through the passage to a closed position at least partially restricting gas flow through the passage so as to permit gas in the secondary chamber to be compressed in response to movement of the piston toward its extended position, thereby reducing a net return force on the piston and decreasing a velocity of the piston.

Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper along a central longitudinal axis. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending between the first and the second longitudinal ends. The surface groove is substantially straight and tilted with respect to a line drawn on the surface portion parallel to the central longitudinal axis. An MR damper including the MR piston ring is also described.

Abstract: A vibration damper with stroke-dependent damping force includes a cylinder in which a piston rod with a piston is axially movable. The piston divides the cylinder into two work spaces filled with damping medium. A bypass between the work spaces is opened or closed depending on the piston position. The piston has a damping valve for at least one through-flow direction formed by a valve body that partially covers a through-flow channel in the damping valve. The valve body has first and second pressure-actuated surfaces on opposite sides of the valve body. The action of the second pressure-actuated surface depends on the position of the piston in relation to the bypass. The first pressure-actuated surface exerts a lifting force and the second pressure-actuated surface exerts a closing force on the valve disk. The second pressure-actuated surface is connected to a control space and a connection channel that overlaps with the bypass depending on the stroke position of the piston.

Abstract: A damper device is provided with a cylinder body and a piston body, and provides braking for movement or relative movement of an object to be braked by attaching at least either the cylinder body or the piston body to the object to be braked. The piston body is provided with a seal ring for sealing between the piston body and the cylinder body. When a pressure difference between an inner space, located between the piston body and a deep inner section of the cylinder body, and the outside becomes a predetermined volume or above due to the movement or the relative movement of the piston body, one part of the seal ring is deflected and deformed so as to open a path for interconnecting the inner space and the outside.

Abstract: A valve mechanism for a gas spring suspension system that equalizes the gas between positive and negative gas chambers when the pressure in the negative gas chamber exceeds the pressure in the positive gas chamber. The suspension system includes a tube, a piston assembly slidably displaceable along the tube and a valve mechanism. The piston assembly separates the tube into the positive gas chamber and the negative gas chamber. The valve mechanism is configured to permit gas flow between the positive and negative gas chambers when the gas pressure in the negative gas chamber exceeds the gas pressure in the positive gas chamber.

Abstract: A piston (10) comprises a first pair of passive flow-control valves (18, 20) [namely, a first compensation valve (18) and a first rebound valve (20)], a second pair of passive flow-control valves (22, 24) [namely, a second compensation valve (22) and a second rebound valve (24)], and a flow-dividing solenoid valve (14) shiftable between a first operating position [in which it allows flow of a damping fluid between an upper chamber and a lower chamber of a shock absorber through the first pair of passive flow-control valves (18, 20) and second pair of passive flow-control valves (22, 24)] and a second operating position [in which it allows the flow of the damping fluid between the upper chamber and lower chamber through only the second pair of passive flow-control valves (22, 24)]. The solenoid valve (14) is normally open (i.e., it is normally kept in the first operating position).

Abstract: A method for controlling the pressure in a compressed-air accumulator of a level-control system of a motor vehicle utilizing a pressure-control apparatus constructed and arranged to adjust the accumulator pressure according to a predetermined index pressure value. The index pressure value is automatically determined by a computing device based on the relative level and/or the load of the vehicle.

Abstract: A suspension component achieves progressive resistance via a secondary bleed valve, which functions as a support for the primary compression valve at higher displacements, in conjunction with a secondary nonlinear spring element configured to alter the force on the piston at high displacements.

Abstract: The invention relates to a damper having a damper cylinder, in which a piston plunger is guided via a piston rod. For the adjustment of characteristic damper values, the flow of a damper fluid can be controlled via control mechanism disposed inside the damper cylinder, which controls the flow of the damper fluid in a first flow direction using a first adjusting element and in a second flow direction using a second adjusting element. According to the invention, the first and second adjusting elements are provided with at least one spring element. The spring rate of at least one of the spring elements can be adjusted for defining a damping behavior using corresponding defining or predetermining elements.

Abstract: The invention relates to a method for absorbing the displacement, under the influence of an external force, of at least one plunger (10,20) in a linear electrodynamic motor comprising a least an induction coil (11, 21) magnetically coupled with the plunger. Said method comprises the steps of: detecting in said induction coil a current induced (I?ind) amplified relative to the induced current. The invention can be applied to cryogenic machines on board space ships.

Abstract: Provided is a piston assembly of a shock absorber, which is simple in structure and is easy to fabricate. The piston assembly of the shock absorber includes: a piston body in which a piston rod reciprocating within a cylinder penetrates a central portion thereof, and a plurality of compression passages and a plurality of rebound passages alternately penetrating the piston body are formed around the piston rod; a compression retainer placed over the piston body, in which a plurality of connection holes corresponding to the compression passages penetrate the compression retainer; and a rebound retainer placed under the piston body, in which a plurality of connection holes corresponding to the rebound passages penetrate the rebound retainer.

Abstract: A two-stage slave cylinder including a housing and a bore extending within the housing. An outer piston is slidably positioned within the bore in the housing, and an outer piston chamber is defined by the bore and the outer piston. The outer piston chamber is connected to a hydraulic fluid source by a fluid passageway. A biasing mechanism acts to bias the outer piston in an unactuated position unless a force is exerted on the outer piston that is greater than the biasing force. A bore is provided in the outer piston, and an inner piston is slidably positioned therein. An inner piston chamber is defined by the bore and the inner piston, and an opening is provided in the outer piston to connect the outer piston chamber to the inner piston chamber. A valve assembly is provided within the opening in the outer piston to control the flow of fluid between the outer piston chamber and the inner piston chamber.

Abstract: A pneumatic cylinder having end position damping of the cylinder piston is controlled by means of a vent path and a control valve, the control valve comprises a control piston, the control side of which is pressurized by a pneumatic pressure which exists in a control chamber. The movement of the control piston into its closing position is pneumatically controlled by the increasing pressure in the damping chamber during the beginning of the damping. No additional components or controls are to be provided, so that the control of the end position damping occurs exclusively by the pressure conditions prevailing at the time when the damping begins.

Abstract: A shock absorber is attached coaxially with a reciprocating rod driven by a reciprocating unit to prevent a bending moment from being applied to the reciprocating rod in absorbing an impact force. The shock absorber has a hollow rod provided with a through hole and an outer cylindrical body mounted outside the hollow rod so as to be movable axially relatively and attached to the reciprocating unit. An accommodating space is formed between the hollow rod and the outer cylindrical body. A spring force in a direction of being relatively directed to one end portion side of the hollow rod is applied to the outer cylindrical body by a compression coil spring. An annular piston for partitioning an accommodating space into two liquid chambers is provided in the hollow rod. When the impact force is applied to the hollow rod so as to be slid to the hollow rod, the liquid flows from one liquid chamber to another liquid chamber through a gap, whereby a resistance force is applied to the annular piston.

Abstract: Disclosed herein is a shock absorber for damping vibration transmitted to a vehicle according to a road state. The shock absorber includes a cylinder and a piston valve disposed within the cylinder and connected to a piston rod. The piston rod includes a hollow chamber formed within the piston rod, a floating piston disposed within the hollow chamber to move up and down and to divide the hollow chamber into upper and lower chambers, and a moving mechanism formed in the hollow chamber to move an operating fluid to upper and lower portions of the floating piston. The shock absorber can change a damping force according to a displacement of the piston rod, thereby improving driving comfort and stability of the vehicle.

Abstract: A stop damper with a damper member including a receiving space inside which a piston is movably guided between an initial and an inserting position. The piston includes a bellows section and a sealing element, the sealing element resting on a sliding surface of the damper member and the bellows section being allocated to a rest section of the damper member at the initial position. To improve a damping characteristic of a stop damper, the rest section includes at least sectionwise a region that enlarges in the direction of the inserting movement of the piston.

Abstract: A floating piston valve includes an annular valve body having a fluid passing hole formed therein, a pair of upper and lower valve discs respectively mounted on upper and lower sides of the valve body to generate damping force, a pair of upper and lower tripod type leaf valve springs respectively mounted on upper and lower sides of the upper and lower valve discs, and a pair of upper and lower coupling supports coupled to the valve body respectively at upper and lower sides of the upper and lower tripod type leaf valve springs. Each of the coupling supports includes an annular support section and a coupling section at least partially formed on an outer edge of the annular support section and is fastened to the valve body through a portion of an outer edge of the valve body.

Abstract: A motion damping device, such as a shock absorber, has a damper valve having a valve body (11) including a first face (20, 23) on a first side of the valve body and a second face (23, 20) on the opposing second side of the valve body. The damper valve also has at least first valving (25, 26, 27, 33, 34, 35) to provide a restriction to fluid flow across the damper valve in a first direction from the second side of the of the damper valve to the first side. The first valving has a first valving disc seat (24, 32) on the second face of the valve body. The first valving disc seat has an outer edge. At least one first valving port (21, 31) extends through the valve body from the first side to the second side and exits the valve body inside the outer edge of the first valving seat. The at least one first valving disc is seated on the first valving disc seat.

Abstract: Disclosed is a double sliding piston valve in which a sliding valve is added to a piston valve to realize gentle variation of damping force. The double sliding piston valve for use in a shock absorber, includes a housing placed in a lower region of a piston to store oil therein, a sliding valve received in the housing, the sliding valve having first and second flow-paths formed therein, pressure springs respectively coming into close contact with upper and lower surfaces of the sliding valve to enable vertical sliding of the sliding valve, and a washer provided below the sliding valve to support the sliding valve, the washer having a center oil hole.

Abstract: Shock absorber provided with a piston having a number of constantly open connecting channels which connect the two sides of the piston, and having a number of connecting channels to be opened and closed by element of a valve. The valve includes a plate valve which under the influence of flow therethrough, i.e. the pressure difference over the piston, on the outward movement of the shock absorber can be closed to a greater or lesser extent. On the inward movement, unimpeded flow of fluid through the piston can occur. A flow-through path is bounded by the corresponding connecting channels and the valve together with the upper side of the piston. In the rest position there is a flow-through possibility for fluid when the shock absorber fixings move away from each other, and when the shock absorber fixings move away from each other more quickly the flow-through cross section gradually decreases until the valve closes completely.

Abstract: A hydraulic shock absorber which includes a piston which is slidably fitted into a cylinder and partitions the cylinder into first and second fluid chambers; and a piston rod which is connected to the piston and slidably penetrates through an end wall of the cylinder, wherein the piston rod penetrates through the piston and includes on the outer circumferential surface of the piston rod at least one groove which communicates between the first and second fluid chambers, and the first and second fluid chambers are communicated with each other through the at least one groove.

Abstract: Damping valve device for a vibration damper, including an actuator that acts on a preliminary stage valve body of a preliminary stage valve. The preliminary stage valve body is arranged in a pre-loading line with a main stage valve body of a main stage valve. The lifting path of the main stage valve body is proportional to the lifting path of the preliminary stage valve body, and the damping characteristic of the damping valve device is influenced by a valve spring arrangement. The preliminary stage valve body controls an adjustable spring compressor that determines the pre-loading of a main stage valve spring is part of the valve spring arrangement.

Abstract: A shock absorber has a compression valve assembly which functions during a compression stroke, a rebound valve assembly which functions during a rebound stroke and a velocity sensitive valve which is in series with one or both of the compression valve assembly and the rebound valve assembly. The compression valve assembly, the rebound valve assembly and the velocity sensitive valve can be incorporated into a piston assembly, a base valve assembly or both.

Abstract: A rotary member that displaces a valve member in an axial direction in accordance with a rotation operation is supported on an adjuster case coaxially with the valve member. A detent mechanism is constituted by a fluid chamber that applies a fluid pressure to the rotary member in a direction for separating from the valve member, a pressure-applying member fixed to the rotary member, and a pressure-receiving member that is fixed to the adjuster to support the pressure-applying member against a pressure of the fluid chamber. By forming an engagement portion that engages with the pressure-applying member in the pressure-receiving member, a dimension of the rotary member of the adjuster and an operation input can be suppressed to be small.

Abstract: An amplitude selective shock absorber includes a cylinder, a piston rod axially movable within the cylinder, a stationary piston valve fixedly mounted on the piston rod to divide a space of the cylinder into a rebound chamber and a compression chamber, a floating piston valve mounted on the piston rod to be movable in an axial direction in the rebound chamber, a stopper secured to the piston rod above the floating piston valve, and frustoconical leaf springs disposed between the floating piston valve and the stationary piston valve and between the floating piston valve and the stopper, respectively.

Abstract: Disclosed is a vibration damper comprising a cylinder in which a piston rod is guided in an axially movable manner. A first piston is mounted stationarily on the piston rod while a second piston that is equipped with at least one valve disk biased by a spring assembly is mounted on the piston rod so as to be axially movable counter to a force of at least one support spring. The spring assembly is provided with at least one spring plate on which the spring assembly rests. The second piston is retained by a fixing sleeve which supports the at least one spring plate. The structural unit encompassing the fixing sleeve and the at least one spring plate is fitted with an axially effective separating joint for a locking connection inside the structural unit. The entire structural unit can be axially displaced towards the at least one support spring.

Abstract: A vehicle damper of variable damping force including a cylinder, a piston and valves is disclosed. The valves have opening/closing parts and supporting parts. The opening/closing parts and the supporting parts are positioned separately so that a sufficient distance is obtained. Lengthening the distance from the supporting parts to the opening/closing parts makes it possible to reduce the opening and closing force of the opening/closing parts and to obtain highly responsive valves.

Abstract: Apparatus for lifting a hatch which can pivot around a pivot axis, especially a hatch of a motor vehicle, by means of a piston-cylinder unit. The piston-cylinder unit has a closed cylinder filled with a pressurized fluid, the interior of the cylinder 6 being divided by a piston into a first working chamber and a second working chamber. A piston rod passes through the second working chamber and is guided to the outside through a seal at the end of the cylinder and then hinged to the hatch, whereas the other end of the cylinder is hinged to a stationary component. A through-opening leading from the first working chamber to the second working chamber, is provided in the piston. The through-opening can be opened by an electrically actuated valve.

Abstract: A hydraulic valve includes a main body, a valve body, a piston, a valve sleeve, a spool and a resilient energy storage member. The valve body and the piston are disposed within the main body. The valve body defines a first chamber, a second chamber, and a cylindrical passage connecting the first chamber and the second chamber. The valve sleeve is moveably disposed in the cylindrical passage. The spool is moveably disposed within the bore of the valve sleeve. The resilient energy storage member may be disposed between the valve sleeve and valve spool. The resilient energy storage member is compressed as pressure is induced in one of the first chamber or the second chamber such that the valve sleeve and the spool move relative to one another so that at least a portion of the shaped aperture is exposed to the first chamber or second chamber to allow a proportional amount of hydraulic fluid to flow between the first chamber and the second chamber.

Abstract: The invention relates to a damping element for a vibration damper that works with hydraulic damping fluid. The fundamental structure of the damping element includes a one-piece base body configured as a circular disk, which has a plurality of first flow-through openings, each having an entry cross-section in a first face side of the base body, as well as a plurality of second flow-through openings, each having an entry cross-section in an opposite, second face side of the base body, as well as circular valve disks on both face sides of the base body, which rest against a support surface of the base body, disposed in the center, and at least partially close off exit cross-sections of the flow-through openings. The exit cross-sections are surrounded by control edges, which form contact surfaces for the valve disks and project beyond the support surface as well as the entry cross-sections.

Abstract: Damping movement device of pieces of furniture which are movable relative to stationary parts. The device has a cylinder with a piston movable in a longitudinal direction, forming a modifiable working chamber filled with liquid medium. The liquid medium is transferred in a throttled manner. A piston rod is sealingly guided and connected to one side of the piston. The movement of the parts of furniture which is to be damped is transmitted to the piston via the outer end of the piston rod facing away from the piston. A volume compensating mechanism is provided. The piston rod is coupled to the piston with overflow ports. The non-return disk with overflow port is moved into sealing contact with the facing piston face. A spring biasing the facing faces of the non-return disk and the piston into the spaced-apart position is arranged between the non-return disk and the piston.

Abstract: A damping force variable valve includes a retainer having a main body connected at a central portion thereof to a high pressure part or portion of a shock absorber and having an outer peripheral region enlarging outwardly, and a spool rod integrally extending from the central portion and formed at a center thereof with a hollow portion having a spool inserted therein. The variable valve further includes a main disc disposed adjacent the retainer, a solenoid unit provided adjacent the spool rod and including a push rod for moving the spool when electrical power is applied, and an operating block installed adjacent the solenoid unit and including an enlarged portion coupled to the outer peripheral region of the main body.

Abstract: A damper includes a damper cylinder, a piston unit comprising a piston ram guided via a piston rod in the damper cylinder, a flow device arranged within the damper cylinder for the passage of a damper fluid flow, which device includes at least one control gap for setting a characteristic damping curve, and an adjustment device arranged within the damper cylinder for controlling the control gap, which device includes at least two spring elements and at least one guide body. The adjustment device includes at least one valve piston that together with the guide body forms the at least one control gap.

Abstract: A gas damper includes a gas pressurized working chamber and valving within the piston to control flow of the gas through the piston. A system is in communication with the working chamber to control the gas pressure within the working chamber in order to control the damping characteristics of the damper. An electronic control unit is utilized to control the opening and closing of the valving within the piston to also control the damping characteristics of the damper.

Abstract: A damper (400) including a pressure-sensitive damping control circuit that selectively permits fluid flow from a first chamber (406a) to a second chamber (448). A piston (410) is supported for reciprocation to vary a volume of the first chamber. A blow-off piston (429) is movable between a closed position, wherein fluid flow through the control circuit is substantially prevented, and an open position, wherein fluid flow through the control circuit is permitted. The damper also includes a first source of pressure. A fluid pressure created by compression of the damper applies an opening force to the blow-off piston tending to move the blow-off piston in a direction toward the open position against a resistance force provided by the first source of pressure. The resistance force is greater than the opening force until the pressure created by forces tending to insert the piston rod into the first fluid chamber exceeds the pressure in the first source of pressure by a predetermined amount.

Abstract: An amplitude sensitive damper apparatus that is provided with an amplitude sensitive valve unit may include a plug coupled to a piston rod to form a spring groove with the piston rod in a predetermined section, a spool member configured and dimensioned to cover the spring groove and slidably coupled to the piston rod to move up and down along the piston rod, wherein the spool member includes a supporting portion that protrudes toward the piston rod from a middle portion of an inner surface of the spool member, upper and lower elastic members that are mounted inside the spring groove to support the supporting portion of the spool member upwards and downwards respectively along the piston rod, and an amplitude sensitive valve that is integrally mounted on an outer surface of the spool member to generate a damping force when the spool member is moving.

Abstract: A damping device includes a cylinder in which a resilient member and a piston are received. A cover assembly and a seal member seal the cylinder and damping medium is filled in the cylinder. The piston includes a piston body, a connecting portion connected with one end of the resilient member, and a neck portion connected between the piston body and the connecting portion. The piston body has an opening penetrating through the piston body. A control valve is movably mounted to the neck portion to control the opening during operation. A piston rod has one end connected with the piston body and another end extending out from the cylinder. A damping member is located between the piston and the cover assembly. The traveling velocity of the piston is controlled by the control valve to close or to open the opening through which the damping medium passes.

Abstract: A steering damper can generate a smaller damping force according to a first damping force characteristic or a larger damping force according to a second damping force characteristic by controlling a flow of hydraulic oil during a steering operation of a steering member. When the associated vehicle is running at a relatively low or medium speed and is not accelerating, and if an operational speed of the steering damper is lower than a predetermined value, damping force according to the first damping force characteristic can be generated in the steering damper. On the other hand, when the operational speed of the steering damper is equal to or higher than the predetermined value, damping force according to the second damping force characteristic can be generated in the steering damper.

Abstract: The invention relates to a rapid recovery shock absorber system with hydraulic end stop, comprising a stem (3) and a body (1), in which a piston (8, 9, 10, 11) runs which is fixed to a tube (71) and which defines at least one upper chamber (S) and one lower chamber (I) in the body (1). A body (32, 32a) in the stem (3) comprises a housing (321), in which a piston (33, 33a) runs which is connected to a rod (7) which slides in the tube (71). A clamp (31), for fixing the shock absorber system to the vehicle, tensioning means (35, 37, 39), exerting a force which tends to displace the piston (33, 33a), sliding in the stem body (32, 32a), driving the displacement of the rod (7) which results in the opening or closing of a section of an oil passage in the lower chamber (I) towards the upper chamber (S) are also provided.

Abstract: A shock absorber comprises a first passage (2a, 2b) and a second passage (15) connecting a first fluid chamber (41) and a second fluid chamber (42). A throttle (12, 14) narrows an inflow of fluid to the first passage (2a, 2b) according to an applied displacement pressure. The displacement pressure includes a fluid pressure in one of the two fluid chambers (41, 42) and a pressure that depends on a velocity of the fluid flow through the throttle (12, 14). A spring (25, 29) biases the throttle (12, 14) in the opposite direction to narrow the fluid flow. The second passage (15) comprises a pair of orifices (16a, 17a). By exerting a pressure between the pair of orifices (16a, 17a) on the throttle (12, 14) in the opposite direction to narrow the fluid flow, the spring load required of the spring (25, 29) is reduced.

Abstract: A hydraulic shock absorber has a cylinder having a hydraulic fluid sealed therein and a piston connected with a piston rod and slidably provided in the cylinder. The piston is provided with a circular main seat portion to form a main valve chamber communicating with an extension passage. Arcuate sub-seat portions are provided in concentric relation to the main seat portion to form sub-valve chambers. A disk valve is seated on the main and sub-seat portions to form clearances between them that always communicate between the main and sub-valve chambers. The disk valve opens upon receiving the pressure in the main and sub-valve chambers. The clearances restrict the flow of hydraulic fluid flowing out through the sub-valve chambers at the beginning of opening of the disk valve to prevent a sharp change in damping force. The concentric arrangement of the main and sub-seat portions facilitates the setting of an initial deflection for the disk valve.

Abstract: A magnetorheological (MR) piston ring includes an MR-piston-ring body disposable within a cylinder of an MR damper. The MR-piston-ring body has a radially inner surface defining a boundary of a longitudinally-extending MR passageway. The MR-piston-ring body includes a surface portion which is slidingly engagable with the cylinder and which has first and second longitudinal ends. The surface portion includes at least one surface groove each defining a secondary MR passageway and extending from the first to the second longitudinal end or each defining an MR cavity extending from one of the first and second longitudinal ends toward, but not to, the other of the first and second longitudinal ends. An MR damper including the MR piston ring is also described.

Abstract: A hydraulic damping device includes a cylinder holding a hydraulic fluid, a piston rod moving in and out of the cylinder and having a pin at one end inside the cylinder, a rigid valve block affixed to the inner end of the pin of the piston rod and having equiangularly spaced through holes, a retainer affixed to the outer end of the pin of the piston rod, a piston coupled to the pin of the piston rod and movable along the pin between the rigid valve block and the retainer and having a plurality of axially extending through holes, a number of the through holes of the piston being respectively aimed at the through holes of the rigid valve block for allowing the hydraulic fluid to pass through the piston in one direction at a high speed during outward stroke of the piston rod and to pass through the piston in the other direction at a low speed during inward stroke of the piston, and a shock absorber that buffers the impact of the rigid valve block when the piston rod is extended out of the cylinder.

Abstract: An end-stop damper including a damper body in the form of a cylinder, wherein a piston is guided so that it is displaceable in the cylinder receiving chamber. An air pressure is formed in the receiving chamber produces a braking force acting on the piston during its displacement. The receiving chamber includes at least one pressure reducing opening and the piston includes a bellows section which is actively connected to the cylinder according to pressure conditions in the receiving chamber. This invention substantially simplifies the structural design of the end-stop damper because the piston and the bellows section are connected to each other so that they are formed in one piece.

Abstract: A damping valve for a vibration damper includes a guide sleeve which slides on the piston rod of a vibration damper. An annular damping valve body which is provided with at least one through-opening is fixed axially by positive engagement on the guide sleeve, and the through-opening is covered at least partly by at least one valve disk which is biased by at least one closing spring which is supported at its end at a spring plate connected to the guide sleeve. The damping valve body and a spring plate which is constructed separate from the guide sleeve form a compression chain between two axially spaced stops of the guide sleeve.