Abstract: A double liner gas cylinder with a straight-walled internal gas cylinder, housed inside a longer tube (14) with an extend area (16) housing outer bushing (25) held in position by an outer tube (26).

Abstract: This invention provides a mono-tube type shock absorber comprising: a cylinder having one closed end, a free piston sliding portion, a piston sliding portion, and a bearing portion provided in an end portion of the cylinder and having a pass through portion; a free piston slidably provided within of free piston sliding portion of the cylinder, the free piston dividing an inside of the cylinder into a gas chamber and an oil chamber; a piston slidably provided within of free piston sliding portion of the cylinder, the piston dividing the oil chamber into two oil chambers; a rod having one end fixed to the piston, the rod being provided to pass through the bearing portion so as to be capable of projection and retraction with respect to the cylinder; and a sealing portion provided in a through portion of the bearing portion, wherein an inner diameter of the free piston sliding portion of the cylinder, in which the free piston slides, is set larger than an inner diameter of the piston sliding portion of the cylind

Abstract: A suspension assembly is provided that includes a shock absorber having a housing filled with hydraulic fluid. An air spring is supported on the shock absorber, and the air spring includes a bladder filled with air. A valve assembly is surrounded by the fluid housing and the bladder. The valve assembly is in fluid communication with the hydraulic fluid and air. The air manipulates the valve and adjusts flow of hydraulic fluid through the shock absorber to adjust damping based upon vehicle load experienced at the air spring. Preferably the valve assembly is located within the inner cylinder head arranged between the piston rod and the outer cylindrical wall of the shock absorber. The valve assembly may include a teeter-totter valve that cooperates with other valves plungers and springs to provide variable damping throughout the vehicle load experienced by the inner spring.

Abstract: A bicycle suspension system that includes an indicator for displaying the travel of a bicycle suspension system in response to an applied load. The system includes an inner tube telescopically engaging with the outer tube along an axis. A biasing mechanism biases the inner and outer tube apart from each other along the axis. The indicator is disposed along a length of the inner and outer tubes. The indicator may include a plurality of markings on the inner tube and a pointer on the outer tube. Each marking corresponds to a distance that the inner and outer tubes may be displaced relative to each other. The suspension system may include an adjustment mechanism that adjusts the distance the inner and outer tubes may be displaced relative to each other in response to an applied load. The rider may select the desired travel by actuating the adjustment mechanism to align the marking corresponding to the desired travel with the pointer.

Abstract: Heat of an electrothermal part of a heater can be transmitted indirectly and efficiently to a pressure medium. A tubular case 6 having one end portion connected to a piston rod 2 airtightly and the other end portion slidably placed in contact with the outer circumference of a cylinder 1 is provided, a mounting hole 15 is formed within a holder 4 for closing an open end on the piston rod 2 connecting side of the case 6, and an electrothermal part 13a of a heater plug 13 is fitted into the mounting hole 15 directly or through a heat conductivity collar 16.

Abstract: An air spring has first and second axially spaced end members with a flexible bellows sealingly clamped to the end members and extending therebetween and forming an intervening air chamber. A flexible elastomeric sleeve having at least one convolution resiliently mounts a rigid restraining cylinder to one of the end members. The cylinder extends co-axially along and outside of the bellows. The flexible sleeve is bonded or snap-fitted to the cylinder.

Abstract: The invention relates to a pneumatic spring assembly comprised of at least one pressure reservoir (1) with a connection to the chassis, with a roll-off piston, a pneumatic spring bellows (2), which encloses a volume-elastic air chamber (3), and with a shock absorber comprising, in turn, a reservoir tube and a piston rod (12) that dips into the reservoir tube in a sliding manner. The pressure reservoir (1) comprises a pressure chamber (4) and a, for the most part, pot-shaped accommodating chamber (5), whereby a shock-absorber bearing (6) comprising an elastomer body (7) and a supporting piece (8) can be placed inside said accommodating chamber (5). The inventive pneumatic spring assembly is characterized in that the pressure reservoir (1) is provided with a dynamic seal (16) in the area of the bottom opening (11) of the accommodating chamber (5).

Abstract: A gas spring includes an outer tube; a base plate; a head plate; an inner tube mounted to extend between the head plate and the base plate; a piston/rod assembly mounted to reciprocate vertically in the inner tube between a retracted, compressed position and an extended, rest position; a valve ring coaxially mounted around the rod to reciprocate between the main piston and head plate; a primary gas chamber; a relief chamber; seals for preventing fluid flow from the primary and relief chambers; a passageway providing communication between the primary gas chamber and relief chamber; and, valve apparatus for controlling fluid flow between the primary and relief chambers. The valve apparatus operates to open and close the fluid flow as a function of the position and direction of travel of the piston/rod assembly.

Abstract: A suspension unit or suspension system includes an accumulator (112) for storing fluid under gas pressure and a motion damping unit (114) for storing fluid under pressure in fluid communication with each other. A valve arrangement (126) is located intermediate the accumulator (112) and the motion damping unit (114) to allow fluid under pressure to flow between the accumulator (112) and motion damping means (114). A piston (122) reactive to movement of the accumulator (112) and motion damping unit (114) with respect to each other is used to control the movement and fluid through the valve (126) so as to adjust the relative positions of the accumulator (112) and the motion damping unit (114). In one embodiment, the accumulator (112) is separate to the motion damping unit (114) and is connected thereto by a flexible hose or other conduit, whereas in another embodiment the accumulator (112) and motion damping unit (114) are a single unit in fluid communication with each other through the valve arrangement (126).

Abstract: A suspension assembly is provided that includes a shock absorber having a housing filled with hydraulic fluid. An air spring is supported on the shock absorber, and the air spring includes a bladder filled with air. A valve assembly is surrounded by the fluid housing and the bladder. The valve assembly is in fluid communication with the hydraulic fluid and air. The air manipulates the valve and adjusts flow of hydraulic fluid through the shock absorber to adjust damping based upon vehicle load experienced at the air spring. Preferably the valve assembly is located within the inner cylinder head arranged between the piston rod and the outer cylindrical wall of the shock absorber. The valve assembly may include a teeter-totter valve that cooperates with other valves plungers and springs to provide variable damping throughout the vehicle load experienced by the inner spring.

Abstract: The gas-hydraulic shock absorber assembly comprises a sleeve member and a ram member movable relative to the sleeve member. In the interior of the ram member, a gas chamber is provided that is pressurized by means of a gas. In the interior of the sleeve member, an oil chamber is provided that is filled with a hydraulic medium and which decreases in volume the more the ram member is moved relative to the sleeve member. Between the two chambers, a gas-hydraulic control assembly is provided. Upstream of the control assembly, there is a bleeding assembly, comprising a transfer channel opening into a portion of the oil chamber remote from the control assembly. Further provided is a bleeding channel, opening into an upper portion of the oil chamber and connecting the transfer channel to the control assembly when the shock absorber assembly is at rest. The bleeding assembly comprises several channels connecting the oil chamber to the control assembly and comprising each a V-shaped valve flap to close the channels.

Abstract: In a hydraulic shock absorber in which a piston is slidably in contact with an inner periphery of an inner tube, a cross sectional area S1 of an annular oil chamber which is sectioned by an inner periphery of an outer tube and an outer periphery of the inner tube is formed larger than a cross sectional area of a piston rod. A check valve which inhibits a flow from an oil chamber to an oil storage chamber at a time of an expansion side stroke is provided in a partition member which is provided in an inner periphery of the inner tube, and a micro flow passage which communicates the oil chamber with the oil storage chamber is provided in the partition member.

Abstract: A vibration damper includes a cylinder in which a piston rod is guided so as to be axially movable. A first piston is mounted stationary on the piston rod and a second piston is mounted so as to be displaceable axially on the rod against a spring force. The cylinder has a work space at the piston rod side, a work space remote of the piston rod, and a work space between the two pistons. Through-openings which are outfitted with valves control a connection between the work spaces. The second piston has at least one return spring on both sides, and the piston is mounted so as to be displaceable axially in two directions against the return springs.

Abstract: Shock absorber, having a cylinder in which a piston rod is arranged as a displacer and which has a piston which subdivides a working space filled with damping medium into two working chambers. Arranged concentrically with this cylinder is an outer tube which, together with the cylinder, forms an annular space sealed off from the atmosphere by seals. The outer tube, together with the piston rod, executes a synchronous movement relative to the cylinder as a function of the reciprocating movement. At least one of the seals of the annular space is arranged in a fixed location with respect to the cylinder, and at least another one of the seals is arranged in a fixed location with respect to the outer tube, so that the annular space has a volume which varies as a function of the reciprocating position of the shock absorber. The annular space is connected via at least one flow connection to at least one of the working chambers.

Abstract: The invention provides a damper assembly (10) comprising a housing (12) defining an inner chamber (22, 24) having a damping fluid disposed therein. A piston rod (14) is slidably retained by the housing (12), and at least partially extends into, the chamber (22, 24). A piston (18) is disposed at a first distal end (21) of the piston rod (14) and strokes inside the housing (12). The piston (18) defines a first chamber (22) and a second chamber (24) within the housing (12) and includes at least one aperture (26) for allowing damping fluid to flow between the first (22) and second (24) chambers. An actuator (30) is disposed within the piston (18) for varying the flow of damping fluid through the aperture (26) between the first (22) and second (24) chambers within the housing (12). The piston rod (14) includes an inner bore (16) that receives pressurized air from an external source for communicating pneumatic control signals to the actuator (30).

Abstract: A damping element has a container tube which is connected to a rolling tube of an air spring, the rolling tube being connected via a spring bellows acting as a rolling bellows to an outer tube which is arranged concentrically and such that it can move axially with respect to the rolling tube, the spring bellows and the rolling tube bounding a gas chamber provided with a gas filling under pressure. The rolling tube is sealed off with respect to the container tube by an O ring in a groove in the container tube, while, at another point on the container tube, projections are arranged as a stop for a front end of the rolling tube in order to dissipate the axial component of the gas pressure acting on said rolling tube. The assembly of the rolling tube on the container tube and the associated sealing by means of the O ring are achieved simply in a cost-effective manner by pushing the tubes together, the position of the tubes in relation to each other resulting automatically as a result of the projections.

Abstract: The invention disclosed is a compact and lightweight hybrid pneumatic-magnetic isolator-actuator capable of large force, substantial stroke and bandwidth actuation with near frictionless operation and vibration isolation with very low break frequency. Pneumatic and magnetic forces are applied to a single carriage comprised primarily of a coaxially arranged air piston and coil. The carriage is driven relative to a frame or housing including an internally mounted cylindrical piston sleeve and magnetic actuator body. A combination of air bearings and air bearing piston construction provide for frictionless motion of the carriage relative to the frame. The pneumatic piston provides the actuation force for both static loads and low frequency dynamic loads. An integrally mounted sensor and control unit determine the pressure error resulting at the pneumatic piston.

Abstract: A piston/cylinder unit, in particular a gas spring, includes a valve device for the operational motion of a piston rod. The valve device is activatable by an activation device, the activation device being connected near an actuation device and being connected to a load contact device, which influences the function of the valve device. The load contact device connects the actuation device to the valve device for the purpose of changing the adjustability of the valve device when the gas spring is loaded.

Abstract: The present invention relates to a speed reducing device of a gas spring device. The piston is slidably moved in the cylinder in the state the piston is adhered to the inner wall surface of the cylinder, and a cutting recess is formed on the outer peripheral surface of the cylinder to easily move the gas in first and second chambers. A concentric gas passage is formed on the surface of the piston which makes contact with the upper washer, and includes another concentric gas passage. An inlet and outlet of the gas passage is opened towards the outer peripheral surface of the piston. A concentric gas passage is formed on the surface of the piston which makes contact with the under washer. The inlet and outlet of the gas passages is opened towards the bottom surface of an annular recess. The gas passage is connected by an axial recess which penetrates the piston.

Abstract: The gas-hydraulic shock absorber assembly comprises a sleeve member and a ram member movable relative to the sleeve member. In the interior of the ram member, a gas chamber is provided that is pressurized by means of a gas. In the interior of the sleeve member, an oil chamber is provided that is filled with a hydraulic medium and which decreases in volume the more the ram member is moved relative to the sleeve member. Between the two chambers, a gas-hydraulic control assembly is provided. Upstream of the control assembly, there is a bleeding assembly, comprising a transfer channel opening into a portion of the oil chamber remote from the control assembly. Further provided is a bleeding channel, opening into an upper portion of the oil chamber and connecting the transfer channel to the control assembly when the shock absorber assembly is at rest. The bleeding assembly comprises several channels connecting the oil chamber to the control assembly and comprising each a V-shaped valve flap to close the channels.

Abstract: A spring having a main gas chamber, a secondary gas chamber and sealing surfaces which, during a portion of the stroke of the piston rod, define a gas tight seal between them to provide two separate gas chambers each providing a force acting on the piston rod in opposed directions to each other to reduce the net force on the piston rod. When the piston rod is near its fully extended position the sealing surfaces provide the gas tight seal and the net force on the piston rod is minimal and in the direction to move the piston rod to its fully extended position. Thus, until the cooperating surfaces are displaced to terminate the gas tight seal, only a slight force is required to initially move the piston rod from its fully extended position. This greatly reduces the impulse or impact force imparted to a press ram upon initial actuation of the fully extended piston rod. A second seal assembly may also be provided which controls the rate at which the piston rod assembly returns to its fully extended position.

Abstract: A pilot chamber is formed at the back of a disk valve for each of the fluid flow systems for the extension and compression strokes. Damping force in a low piston speed region is controlled with a pressure control valve. The valve opening pressure of the disk valve is controlled by varying a pilot pressure introduced into the pilot chamber from a cylinder's hydraulic fluid chamber through a cut portion in a piston bolt and an orifice groove formed in a fixed member supporting the disk valve, thereby controlling damping force in a high piston speed region. A sharp pressure change occurring when the stroke direction of a piston rod changes is attenuated by the restricting action of the orifice groove so as not to be readily transmittable to the pilot chamber.

Abstract: A gas spring includes an outer tube; a base plate; a head plate; an inner tube mounted to extend between the head plate and the base plate; a piston/rod assembly mounted to reciprocate vertically in the inner tube between a retracted, compressed position and an extended, rest position; a valve ring coaxially mounted around the rod to reciprocate between the main piston and head plate; a primary gas chamber; a relief chamber; seals for preventing fluid flow from the primary and relief chambers; a passageway providing communication between the primary gas chamber and relief chamber; and, valve apparatus for controlling fluid flow between the primary and relief chambers. The valve apparatus operates to open and close the fluid flow as a function of the position and direction of travel of the piston/rod assembly.

Abstract: A suspension strut includes a housing assembly including first and second opposed housing members. The first and second housing members are relatively movable along an axis. At least the first housing member includes an engagement surface. At least one compressible spring member is interposed between the first and second housing members. The spring member includes a peripheral portion. The strut is configured such that, when the first and second housing members are relatively displaced along the axis in a prescribed direction, the spring member is axially compressed to provide a spring force opposing further relative displacement between the first and second housing members in the prescribed direction, and the peripheral portion frictionally engages the engagement surface over an area of engagement to provide dynamic damping between the first and second housing members.

Abstract: A stop assembly for predetermining the maximum downward travel distance or rebound of a vehicle axle/suspension system includes an adjustment cam. A chain for heavy-duty applications, or a woven nylon strap for lighter-duty applications, is immovably attached at its lowermost end to each suspension assembly beam of the axle/suspension system. An uppermost end of the chain is immovably attached to the cam, which in turn is pivotally captured in a bracket assembly immovably attached to the vehicle frame. An easily accessible adjustment bolt passes through the bracket assembly and bears on the cam, so that upon rotation of the bolt using a wrench or similar tool, the chain, and in turn the suspension assembly beam and the axle captured in the beam, can be selectively vertically repositioned by the pivoting cam to predetermine the maximum system rebound during vehicle operation.

Abstract: Oscillating damper comprising: a housing (12) defining a chamber (14) filled with damping fluid, an oscillating plate (22), movable within the chamber (14) and placed so as to divide the chamber (14) into two sections of variable volume (24, 26), and at least one passage (28) created in the oscillating plate (22) to enable the fluid to pass from one section to the other during the motion of the plate (22). The damping fluid is a magneto-rheological or electro-rheological fluid and an electrically-controlled excitation device (30) is placed in correspondence with the passage (28) to control the outflow resistance of fluid passing through the passage (28).

Abstract: An air chamber (53) of a damping force adjusting mechanism (49) disposed in a hydraulic shock absorber (3) of a damping force adjusting type communicates with an air chamber (7) of an air spring through a tubular path (57). A free piston (51) is transferred in accordance with the pressure of the air chamber and a spool (46) is transferred to shift a damping force. The damping force presents a soft characteristic both on the extending side and on the retracting side in a usual status, presents a hard characteristic on the extending side and a soft characteristic on the retracting side when the pressure of the air chamber is high, and presents a soft characteristic on the extending side and a hard characteristic on the retracting side when the pressure of the air chamber (7) is low. The damping force can be obtained, which approximates the damping force control on the basis of a so-called sky-hook theory.

Abstract: The method includes making a fluid communication channel (44), which has a selectively variable cross-sectional area profile, in the inner face of a gas spring cylinder (32) so as to permit fluid communication at different selective rates bypassing around or across the piston assembly (68) of the gas spring (52)as the piston assembly (68) moves within the cylinder (32). Preferably the cross-sectional area profile of the fluid communication channel (44) is initially substantially the same throughout the length of the channel(44) and is thereafter selectively changed in certain portions of the channel (44) so as to restrict and in some instances block gas or fluid flow through the fluid communication channel (44).

Abstract: A magneto-rheological (MR) damper provides a higher than minimum level of damping when a power source to the MR damper is not supplying a control current. The present invention damper includes magnets positioned to direct a magnetic flux across a MR fluid path. The fluid path is created when a rod and piston assembly stroke the fluid though a control valve assembly attached to a damper chamber causing a resistance to MR fluid flow. An electric coil cancels an effect of the permanent magnets when the control current is available to allow a control circuit more operating range. The permanent magnets allow for damping when no control current is available.

Abstract: A shock absorbing device includes two members movable relative to each other, and one or more air envelopes disposed between the members for cushioning purposes. One of the members is a housing having a chamber for slidably receiving a piston and a tube of the other member. A cover is secured to one end of the housing. The tube is slidably engaged through the cover. A pump includes a casing having an opening coupled to a port of the housing for pumping an air into the housing and for providing a pressurized air in the housing.

Abstract: A brake mechanism which permits adjustment of the outer reach or extent of an elastomeric ring about the periphery of the brake. The adjustment is effected by engaging and bending the elastomeric ring seal to a greater or lesser extent depending upon the axial relationship of the component parts forming the brake.

Abstract: A gas shock absorber has a pressure tube which defines a working chamber. A piston divides the working chamber into an upper working chamber and a lower working chamber. A series of extension passages extend through the piston and are opened and closed by an extension valve assembly. A series of compression passages extend through the piston and are opened and closed by a compression valve assembly. An open flow path defined by the extension valve assembly extends through the piston between the upper and lower working chambers. A rod guide assembly is located between the pressure tube and a piston rod. The rod guide assembly includes an oil chamber for sealing and lubricating the piston rod.

Abstract: A hydraulic and pneumatic cylinder (10) for use on a vehicle (100) to improve the handling of the vehicle in a turn or curve. The cylinder repositions the rear wheel (108) of the vehicle in response to a change in the speed of the vehicle. When the vehicle enters a turn and decelerates, the piston of the cylinder moves to the extended position. When the vehicle exits the turn and accelerates, the piston of the cylinder moves to the compressed position.

Abstract: A shock and acoustic mount for reducing transmission of forces between two relatively moveable members such as a mounted component and a supporting structure, providing a compressible fluid spring with large allowable relative movement of the mounted component and support structure. The mount comprises a casing, a piston shell with one end disposed in the casing and another end extending outside of the casing, and a piston housed in the piston shell, all relatively moveable in response to external axial forces. In one embodiment, the mount is filled with a compressible fluid, such as air, providing an air spring. The piston is sealingly bonded to the inner surface of the piston shell, the bond accommodating acoustic and vibration forces by deformation of the bond material. An annular seal between the piston shell and the casing accommodates large and shock forces.

Abstract: A pressure vessel which is filled with at least one medium which is prestressed by a mass of gas which is enclosed in a variable-shape envelope, in particular for volume compensation in a vibration damper. The envelope includes a wall in which a pressurized gas is enclosed, the wall being at least partially formed from a barrier layer and the envelope being composed of a plurality of individual parts. An outside coating, which seals an end face of the envelope, is present at least at an edge-side contact region of the individual parts of the envelope.

Abstract: A device to absorb impact energy between an impacted component and a component to be protected from the effects of the impact (in particular between the bumper bracket (1) and the frame side rail of a vehicle). The device has a deforming section (3) to plastically absorb energy (that is between the bumper bracket (1) and the frame rail), and a hydraulic part to elastically absorb energy. The hydraulic part is before the deforming part (3) (viewed in direction of impact) inside the frame side rail. With this design, it is possible to have a large plunger diameter for the hydraulic section and an aluminum construction.

Abstract: The present invention relates to a hydropneumatic shock absorber. This new telescopic system comprises an outer sliding tube, an inner sliding tube and structure for adjusting the braking level of the shock absorber in expansion. Fastened on the base of the outer sliding tube is the bottom of a barrel on which rests an elastic structure, such as a counter-acting spring, which pushes on the inner sliding tube in the expansion stroke. The inner sliding tube carries at its internal end a bell which cooperates with a stop spring when in the expansion stroke. The liquid filled barrel contains an axially movable piston connected to the closure plug assembly with the piston contains a first valve, which opens only in the compression phase, and a second valve, which acts as variable throttle and is controlled by the padded end of a screw axially placed within the support tube. By acting on a screw, the expansion braking level of the shock absorber can be adjusted.

Abstract: In a self-pumping type hydraulic shock absorber, an outer cylinder is provided to cover an outer circumferential surface of a cylinder. The outer cylinder is formed to have a small-diameter portion, a mid-diameter portion and a large-diameter portion. A reservoir is formed between the large-diameter portion and the cylinder to communicate with upper and lower cylinder chambers. A cylinder member is fitted onto the mid-diameter portion and the large-diameter portion of the outer cylinder to form an oil tank between the cylinder member and the outer cylinder. A suspension spring (a coil spring) is provided between a spring seat attached to the small-diameter portion of the outer cylinder and a spring seat connected to a piston rod. Thus, the reservoir and the oil tank are provided inside the coil spring, so that each of the reservoir and the oil tank can be made to have a sufficiently large volume and the hydraulic shock absorber requires less space for mounting.

Abstract: The present invention relates generally to front suspension fork assemblies for bicycles, and provides an improved suspension fork comprising an adjustable compression system for quick and easy adaptation to various types of terrain. The front suspension fork of the present invention comprises a pair of rigidly connected parallel fork legs, with each fork leg having at its bottom end a dropout for connection to the axle of a wheel. Each fork leg further comprises a shock absorber positioned therein and comprising a helical coil spring to urge expansion of the sliding tubes, flow dampers, and damping fluid within the cavities of the sliding tubes to dampen the movement of the sliding tubes in compression and expansion. Each flow damper comprises a flexible shim which opens in compression or expansion to increase the flow of damping fluid. Varying the flexibility of the shims also varies the damping effect of the shock absorber.

Abstract: On an outside of a damper main body (1) of an inverted type of damper, a cylindrical case (12) which is coupled to a damper rod (2) is provided so as to be movable up and down. Between the damper main body (1) and the case (12), there is formed a pressure chamber (13) filled with a pressure medium of low boiling point which varies between a gaseous state and a liquid state. By use of a heater (16) which is disposed inside the pressure chamber (13) the pressure medium is heated and evaporated, whereby the vehicle height is increased by the vapor pressure of the pressure medium. In the above-described damper with a vehicle height adjusting function, the heater (16) is arranged to be easily mounted and dismounted to thereby improve the ease with which the maintenance is performed. The influence on the suspension stoke which is caused by the presence of the heater (16) is also minimized. The heater is formed into a bar heater (16).

Abstract: A suspension damper includes a tube and a damping piston assembly disposed within the tube and slidably mounted therein for reciprocal movement in the tube. The suspension damper also includes a piston rod extending through the tube and connected to the damping piston assembly, a rod guide assembly closing one end of the tube and a self-aligning rebound cut-off disc carried in the tube between the rod guide assembly and the damping piston assembly and cooperating with the rod guide assembly to provide a rebound cut-off effect and to compensate for misalignment between the piston rod and the damping piston assembly.

Abstract: A piston-cylinder unit, comprising a cylinder which is subdivided by a piston on a piston rod into two working chambers. Between the two working chambers, there is a fluid connection which can be blocked by means of a valve arrangement having at least two individual closing valves arranged in series, each with a valve inflow side and a valve outflow side. The valves open sequentially. In the flow path between the individual valves, there is a throttle arrangement which produces a pressure reduction between the valve outflow side of the first closing valve towards the valve inflow side of the following closing valve. As the opening of the first closing valve increases, the effect of the throttle arrangement decreases; to the same extent, the pressurization increases on the valve inflow side of the following closing valve. The valve arrangement features two flow-through directions and is made so that each can be blocked.