Abstract: In an illustrative example, an oscillation damper for damping the steering movement of the handle bar of a motorcycle comprises a cylinder and a piston rod axially movable with respect to the cylinder. A damping piston is provided at the inner end of the piston rod and divides the cavity within the cylinder into two working chambers. These working chambers are interconnected by at least one axial bore through the piston. Valve discs are provided on both axial end faces of the piston. These valve discs are fixed to the piston in their respective central areas. Circumferential areas of the valve discs define circumferential gaps with the respective end faces. In response to the velocity of axial relative movement of the piston rod with respect to the cylinder the circumferential areas of respective valve discs are approached to the respective end faces. So the damping resistance is increased.

Abstract: The system includes at least one semiactive damper whose switching between high damping and low damping states is at times delayed until the relative velocity across the damper is no greater than a preselected low magnitude, or until the energy stored by a resilient deformable system member is no greater than a predetermined magnitude, or until the first to occur of either of the foregoing events.

Abstract: A method and apparatus for absorbing mechanical shock is disclosed. The apparatus comprises a pressure cylinder forming a working chamber having first and second portions operable to store damping fluid. The apparatus further comprises the first valve for controlling the flow of damping fluid between the first and second portions of the working chamber during compression of the shock absorber. In addition, the apparatus further comprises a pressure chamber in fluid communication with the first portion of the working chamber and the first valve. A solenoid is also provided for regulating the flow of damping fluid between the pressure chamber and the second portion of said working chamber. A second valve is further provided for controlling the flow of damping fluid between the first and second portions of the working chamber during rebound of the shock absorber.

Abstract: An impact damper for a motor vehicle comprises two fluid chambers. These fluid chambers are interconnected by a fluid passage. In case of an impact of the motor vehicle against an obstacle, the fluid flows from one fluid chamber to the other fluid chamber through the throttled passage. If the impact occurs with a high velocity beyond a predetermined velocity, the impact damper behaves like a rigid body. It may therefore occur that the vehicle is damaged to a higher degree than it would in case of lack of the impact damper. For preventing such situation, the passage is provided by perforated and sandwiched discs. One disc acts as a support disc, one other disc acts as a throttling disc. The throttling disc is provided with a weakening line and is broken at a predetermined pressure different between the two fluid chambers. After rupture has occurred, the flow resistance through the passage is reduced and therefore the rigid behavior of the impact damper is eliminated.

Abstract: A shock absorber is provided a piston stroke dependent variable shock absorbing characteristics by a first and second flow restrictions associated with a piston. The first and second flow restrictions are arranged in a fluid path for communicating first and second working chambers defined within a shock absorber cylindrical housing in series. The first flow restriction associated with an orifice forming a part of the fluid path and has a predetermined relief pressure, for providing a predetermined first fixed flow restriction rate in response to a pressure difference between the first and second chambers smaller than or equal to the relief pressure and providing a second variable flow restriction rate in response to a pressure difference between the first and second chambers greater than the relief pressure. The second flow restriction is associated with the orifice for providing a third variable flow restriction rate variable depending upon the pressure difference between the first and second chamber.

Abstract: The fluid circuitry connecting variable volume chambers of the semiactive damper includes valve assemblies which collectively effect mechanical implementation of a preselected damper control policy that is based in part upon changes in the sign of the absolute velocity of a supported member of the system of which the damper forms a part. One of the valve assemblies has an inertial body which is connected to a movable system member but which remains substantially stationary during system operation. The inertial body and a valve member of the assembly are interconnected by a linkage which in one embodiment includes a frictional type connector, and which in another embodiment includes a dashpot.

Abstract: A hydraulic shock absorber has a disk valve assembly which is formed by successively stacking up a first disk valve having arc-shaped or circumferentially extending opening provided therein at positions close to the inner periphery thereof, a second disk valve having notches which extend from the outer periphery thereof to the radially outer edges of the corresponding openings provided in the first disk valve, and a predetermined number of annular third disk valves. A respective such disk valve assembly is provided at the downstream end of each of the extension- and contraction-side passages which are formed in a piston. Thus, it is possible to obtain a higher level of damping force in a low piston speed region than in the case of a conventional valve mechanism that uses a fixed orifice, and damping characteristics can be set as desired.

Abstract: Operation of a continuously variable semiactive damper of the system is modified so as to reduce generation in the system of undesirable shocks and noise. The modifications include delaying some or all of the changes in the on/off states of the damper, and/or limiting the rate and/or extent of changes in the damping coefficient of the damper at certain of the times when the damper is in an on state.

Abstract: A shock absorber including a piston with two relatively movable elements defining a variable-sized, fluid-filled space. The size of the space is decreased when subjected to external fluid pressure and fluid flow through the piston is modified in response to such decrease.

Abstract: A piston and cylinder arrangement, which includes a piston and piston rod assembly and which is filled with a damper-fluid, is attached to an auxiliary tank by a flow channel. A first restriction in the piston and piston rod assembly substantially controls the low velocity flow of the damper fluid during extension strokes and a second restriction in the piston and piston rod assembly substantially controls high velocity flow of the damper fluid during the extension strokes. A third restriction in the flow channel substantially controls the low velocity flow of the damper-fluid during compression strokes, and a fourth restriction in the flow channel substantially controls the high velocity flow of the damper-fluid during the compression strokes. Substantially unrestricted flow of the damper-fluid through the piston and piston rod assembly is permitted during the compression strokes, and substantially unrestricted flow of the damper-fluid through the flow channel is permitted during extension strokes.

Abstract: A hydraulic damper has a valve mechanism adapted to generate a damping force during extension and contraction strokes of the damper. The valve mechanism includes a disc valve assembly consisting of a main disc valve for generating a damping force and an orifice for generating a damping force in low operation speed region of the damper. The orifce is provided with an additional disc valve for controlling the damping force generated.

Abstract: A damper of the semi-active type is controlled such that the damping forces generated by the damper, in response to relative movement between spaced members interconnected by it, are caused to be of minimal (ideally zero) magnitude when the product of the relative displacement between the members and the relative velocity between the members is greater than zero. The foregoing control policy may be implemented by purely mechanical elements, or by electronic elements of relatively simple and inexpensive types.

Abstract: The invention relates to an arrangement for damping shifting movements in a mechanical, synchronized multispeed transmission. Where such shifting movements are performed with the aid of a servo-mechanism, for exmaple a pneumatic piston cylinder unit, there is the risk that the gear teeth will be damaged when brought into engagement with each other. In the arrangement according to the invention, a pressure medium-filled damper is used without any communication with a separate pressure medium reservoir, thus eliminating the risk of malfunction due to foam formation in the pressure medium as well as achieving a desirable damping of the shifting movement. The invention is characterized for this purpose in that the piston in the damper is arranged on a piston rod which extends through the cylinder portion of the damper, so that upon relative movement between the piston and the cylinder portion, the volume of the damper filled with pressure medium remains constant.

Abstract: A frictionless hydraulic damper having a cylinder and a piston head and piston rod connected to the piston head, with the piston head dividing the cylinder into chambers on opposite sides thereof and with the piston rod extending beyond the cylinder, and with sealed bellows extending between the end walls of the cylinder and opposite sides of the piston which confine the fluid to the space between the outside of the bellows and the wall of the cylinder and thus prevent leakage of hydraulic fluid from the cylinder and eliminate the need for fluid seals on the piston rod.

Abstract: A motorcycle front fork assembly is disclosed in which a hollow damper rod is connected at its lower end to lower end of a hollow fork leg which telescopically receives an upper hollow fork tube and with a piston at the upper end of the damper rod engaging the interior surface of the fork tube. A float is positioned within the fork tube to float on the fluid within the fork tube. A float tube in which the float is positioned can be provided above the damper piston rod and including a fluid regulation valve. At least one compression port can be provided for fluid communication between a compression chamber defined between the fork leg and the damper rod below the lower end of the fork tube and a valve provides one way communication from the interior of the damper rod to the compression chamber during extension of the stroke of the fork assembly. The valve can include a slide that can close off or open a replenishment hole and a fluid passageway in the slide which is spring biased closed but can be opened.

Abstract: This valve comprises a tubular body (66) containing a hollow slide (68) mounted axially slidably in a sleeve (69), itself sliding in the body (66) along the axis (X--X) of the valve, a spring bearing on the body and pushing the slide (68) up against an annular end (73) of the sleeve (69), normally held by means of its opposite end (79) up against a cover (82) for closing the body (66) on the opposite side to its central orifice (67); the cover (82) and the sleeve (69) have radial ports (88, 81), the body (66) being contained in a tubular casing (34) having conduits (92, 96), fluid passages (89, 93, 94, 95, 40) also being provided to allow the valve to open in both directions as a result of the hydraulic pressure.

Abstract: A frictionless hydraulic damper including a cylinder having end walls mounting the opposite ends of a shaft in bushings with a clearance, bellows seals between each end wall and the portions of the shaft extending beyond each end wall, a piston head on the shaft within the cylinder, hydraulic fluid in the cylinder and in both bellows seals, an orifice construction located relative to the piston head for permitting flow of hydraulic fluid past the piston head to produce damping, and a conduit in the shaft for effecting communication between the two bellows. The damper as described above also functions as a snubber by including a valve construction which selectively closes the orifice construction. The damper as described above also includes structure which effectively closes off the clearances at the relevant bushings when the piston head travels above a predetermined velocity, to thereby prevent leakage past the bushings and thus enhance the snubbing action.

Abstract: Hydraulic adjustable vibration damper with a damping piston, which divides the work cylinder into two chamber halves, whereby the two chamber halves are connected with one another by a bypass, in which an electromagnet controls the bypass. The bypass valve located in the bypass includes an axially-movable valve body which works together with a passage and which is controlled by the adjustment apparatus, and at least one spring-loaded valve which operates as a function of the pressure connected in series with the valve body.

Abstract: A retarder, suitable when mounted in association with a rail of a railway track for reducing the speed of a wagon rolling along the track, includes an hydraulic unit which comprises a hollow member, a piston slidably housed in that member, and a piston rod. A portion of the hydraulic unit is, for retardation of the wagon, disposed in the path of a wagon wheel. When that portion is engaged, directly or indirectly, by a wheel it is deflected by, and out of the path of, the wheel to permit the wheel to pass the retarder. The ratio of the diameter of the piston to the diameter of the piston rod is in the range 2.80:1 to 6.00:1 and the ratio of the diameter of the piston to the length of stroke of the hydraulic unit is in the range 0.53:1 to 1.20:1.

Abstract: Apparatus for hydraulic damping has a housing (22) having a chamber (30), the chamber (30) dividing the housing (22) into two enclosures (18, 19), between which enclosures (18, 19) fluid may flow through the chamber (30), the chamber (30) having a first port (34) and a second port (36) each being in communication with a respective one of the enclosures (18, 19) and a member (31) arranged inside the chamber (30) such that increase of fluid pressure difference between the ports (34, 36) in either direction causes the member (31) to be deflected elastically so as to allow flow of fluid between the enclosures (18, 19) in the respective direction, the incremental deflection of the member (31) for a particular incremental increase of fluid pressure difference increasing at increasing fluid pressure difference.

Abstract: In a steplessly adjustable hydropneumatic device the spring chamber of which is arranged at the piston rod exit end and which works with a liquid locking, a very simple hydraulic locking is obtained even for high traction stressing upon the piston rod in that both an annular separator piston and the partition are arranged in the inner chamber of the container, which is penetrated by the piston rod. For the hydraulic traction locking in the case of traction forces exerted suddenly upon the piston rod a valve device is provided which cooperates with the piston rod.

Abstract: A liquid spring shock absorbing device 8 comprising an hydraulic piston 10 with an integral surge valve 14. The hydraulic piston 10 is positioned within a fluid filled piston housing 12 and is made up of a piston body 16, a spring reaction plate 22 and a piston heat 18. A large annular spring 30 and a small annular spring 36 are positioned adjacent to the spring reaction plate 22. Short duration shocks are transmitted by the fluid to cause rotation of annular spring 36 which opens relief valve port 42. Long duration, high intensity shocks cause compression of both annular springs, opening of relief valve port 42 and movement of hydraulic piston 10.

Abstract: An adjustable shock absorber for motor vehicles comprises a cylinder containing damping fluid, a piston rod arranged to be axially displaceable in the cylinder, and a damping piston secured to the inner end of the piston rod. The damping piston divides the cylinder chamber into two working chamber compartments and is provided with fluid flow passages which produce damping forces, the effective cross-section of these flow passages being controllable by a throttling member and an electromagnetic drive controlling the throttling member, with the electromagnetic drive including a coil winding which is mounted in the damping piston. In order to achieve improved control of the damping force the throttling member is under the influence on the one hand of the fluid pressure difference between the two working chamber compartments and on the other hand of a restoring force which is created by the electromagnetic drive.

Abstract: An adjustable shock absorber for motor vehicles has a cylinder containing damping fluid, a piston rod arranged to be axially displaceable in the cylinder, and a damping piston secured to the inner end of the piston rod. The damping piston divides the cylinder chamber into two working chamber compartments and is provided with fluid flow passages which produce damping forces, the effective cross-section of these flow passages being controllable by a throttling member and an electromagnetic drive controlling the throttling member, with the electromagnetic drive including a coil winding which is mounted in the damping piston. In order to achieve improved control of the damping force the throttling member is under the influence on the one hand of the fluid pressure difference between the two working chamber compartments and on the other hand of a restoring force which is created by the electromagnetic drive.

Abstract: A frictionless hydraulic damper including a cylinder having end walls mounting the opposite ends of a shaft with a clearance in labyrinth seals, bellows seals between each end wall and the portions of the shaft extending beyond each end wall, a piston head on the shaft within the cylinder, hydraulic fluid in the cylinder and in both bellows seals, an orifice construction located relative to the piston head for permitting flow of hydraulic fluid past the piston head to produce damping, and a conduit in the shaft for effecting communication between the two bellows. The damper as described above also functions as a snubber by including a valve construction which selectively closes the orifice construction.

Abstract: A piston assembly for a shock absorber includes a first set of one or more ports controlled by two valve mechanisms, a second set of ports controlled by a single valve mechanism, and a third set of ports uncontrolled by any valve mechanism. All three sets of ports conduct fluid during the compression and rebound strokes.

Abstract: A playground unit having a rotatable horizontally disposed deck adapted to support at least one passenger is provided with a control device operatively connected to the deck to limit the rotational speed thereof. The control device is a hydraulic governor comprising a fluid reservoir, a pump, and a valve with interconnecting fluid lines and check valves providing appropriate directional flow of fluid between the reservoir, pump and valve. The valve automatically moves between an open and closed position depending upon the rotational speed of the unit. The force required to maintain the rotational speed of the playground unit is much greater when the valve is closed as compared to when the valve is open.

Abstract: A piston assembly for a shock absorber includes a first set of one or more ports, controlled by two valve mechanisms, which conduct fluid only during the rebound stroke of the piston. A second set of ports, controlled by a single valve mechanism, conducts fluid during all compression and rebound strokes. A third set of ports uncontrolled by any valve mechanism conducts fluid during all compression and rebound strokes.

Abstract: A telescopic hydraulic shock absorber for a motor vehicle has a piston with a frustoconical valve element that provides a bypass passage from the rebound chamber to the jounce chamber during a low velocity rebound stroke of the piston with respect to the pressure tube. The frustoconical valve element is constructed to be sufficiently resilient to become seated and close off the bypass passage in response to a relatively high velocity rebound stroke such that all fluid is forced through the rebound ports and the rebound valve to provide higher damping than when the bypass passage is open.

Abstract: A bidirectional relief valve is provided which has a slidable valve element provided with first and second groups of ports which are positioned on opposite sides of a fixed port in the valve body when the slidable valve element is in a neutral position. The valve element may be moved in either direction from the neutral position in response to the differential pressure across the damping head under selected conditions of preload which may be different in each direction. The movable valve element includes a stem portion of relatively small diameter and a larger diameter head portion in which the first and second ports are located. In order to prevent an excessive pressure build up, or overshoot, in response to a shock wave of large magnitude in either direction, the movable valve element is given an initial acceleration by employing the relatively large area of the valve head.

Abstract: A damping assembly for fluid filled sock absorber having a cylinder and a rod slidable therein for movement in opposite directions from a static position includes a damping head mounted on the rod and having a plurality of bi-directional flow control or relief valves in communication with fluid chambers on opposite sides of the damping head which permit fluid flow between the chambers under selectively controlled predetermined parameters. Each bi-directional relief valve includes a unitary valve element having first and second ports which are positioned on opposite sides of a fixed port on the damping head when the valve element is in a neutral position. The valve element may be moved in either direction from the neutral position in response to the differential pressure across the damping head under selected conditions of preload which may be different in each direction. Also, the flow characteristics in either direction may be independently selected by appropriately shaping the first and second ports.

Abstract: A linear motion damper is disclosed which comprises a hollow sleeve member, a rod reciprocating within the sleeve member, and a piston adapted to engage a fluid filled cylinder to provide resistance to linear motion by the exertion of lateral fluid pressure between the rod and the sleeve. The damper of the present invention exhibits greater efficiency and durability in operation, and is adaptable for a wide variety of applications.

Abstract: A hydraulic shock isolator damping valve exhibiting variable damping depending on degree of valve extension is described which comprises a hydraulic cylinder defining closed fluid reservoirs at each end, a piston within the cylinder and interconnecting the structural members between which relative movement is damped, the piston having first and second axially spaced portions sized for slidably engaging the inner surface of the cylinder and including an intermediate third axial portion of reduced outer diametric size, the first and second portions each including a predetermined number of axial holes sized for displacement of fluid through the piston in response to movement of the piston through the fluid, and an annular member of outer diameter smaller than the first and second portions slidable on the third portion between confronting surfaces of the first and second portions, the annular member including a pair of confronting peripheral flanges, each including axial holes smaller in size and corresponding in

Abstract: A compensating rope sheave tie-down uses a hydraulic control system comprising various valves to control sheave motion. The sheave is permitted by the control system to move up and down slightly at slow rates, but is held in place if a high rate occurs. The control also permits the sheave to drop down to apply tension to the compensating rope.

Abstract: A hydraulic damper includes a cylinder containing hydraulic liquid, a piston slidable in the cylinder and partitioning the interior of the cylinder into two liquid chambers, a passage formed through the piston to communicate the two liquid chambers, a piston rod connected to the piston and extending out of the cylinder, and a valve for controlling the liquid flow in the passage. The piston is axially displaceable relative to the piston rod by a limited amount, and the valve comprises an annular disc mounted on the piston rod and cooperating with one side surface of the piston when the piston abuts with the disc when the piston displaces in one direction and separating from the piston to form a clearance therebetween which acts as an inlet of the passage when the piston displaces in the opposite direction.

Abstract: An apparatus for controlling hoist control lever velocity on hydraulic cranes. The device is connected to the hoist control lever via a linkage. The device contains a housing which defines a fluid circuit. A slidably mounted pressurizing component communicates with the fluid circuit and is connected to the linkage. The fluid circuit contains a flow restricting device. When the hoist control lever is moved from a first position, wherein the hoist is stationary to a second position, wherein the hoist is moving, the linkage exerts an inward force on the pressurizing component moving the pressurizing component from a neutral to a pressurizing position. Such movement in turn induces a pressure build-up within the fluid circuit. Flow restricting device within the fluid circuit exerts a back pressure on the pressurizing component thereby through the actions of a the pressurizing component and the linkage limits the velocity of the hoist control lever.

Abstract: A shock absorber comprises a cylinder and a piston rod passing through at least one end of the cylinder. A piston unit is mounted on the piston rod and divides the cavity within the cylinder into two working chambers. A damping fluid is contained within the cylinder. The working chambers are interconnected across the piston unit by first and second branch flow passages arranged in parallel. First and second flow valves are associated with these first and second flow passages, respectively, and operate to dampen movement of the piston rod in at least one direction in dependency on the velocity of movement. The first branch passage flow valve is normally open and closes only when a predetermined velocity of movement is exceeded. The second branch passage flow valve is normally closed and opens only when the pressure differential between the working chambers exceeds a predetermined value. Closing of the first branch passage flow valve increases the damping effect.

Abstract: A control to automatically adjust the air bleed screw on a pneumatic dashpot to alter the return speed of a scanning carriage. At the start of the carriage flyback, an end of scan position signal is generated and a second signal is generated when the carriage has reached the home position. These two signals conveyed to control logic determine the time period of the scan flyback. The time period of scan flyback is compared to an acceptable window or range of flyback time periods. If the scan flyback time period is outside the range of acceptable time periods, an adjust drive signal is conveyed to an adjust solenoid. The activation of the solenoid causes the solenoid armature to move a ratchet wheel into engagement with the pneumatic dashpot air bleed screw.

Abstract: A shock absorber is disclosed having an outer cylinder closed at one end thereof, a hollow inner cylinder closed at one end and opened at an another end thereof, the open end being inserted in the outer cylinder, a guide member for guiding the inner cylinder slidably in the outer cylinder, a member for generating a damping force, the damping force generating member being connected to the open end of the inner cylinder, and having an orifice for throttling flow of hydraulic fluid from a chamber in the outer cylinder to a chamber in the inner cylinder, the orifice being in a central portion of the inner cylinder, and a plate-like stop provided between the inner cylinder and the damping force generating member for retaining the damping force generating member against the damping force within a predetermined range, the stop having an aperture greater than the orifice.

Abstract: Two-chamber motor mount with hydraulic damping, especially for vehicles, including an upper and lower chamber having rubber-elastic walls and being filled with liquid, the upper chamber being of hollow conical construction, a holding flange disposed between the walls of the upper and lower chambers, an intermediate plate formed with a throttle orifice located in vicinity of the holding flange, the upper and the lower chambers being connected to one another through the intermediate plate with the throttle orifice for preventing an hydraulic response for high frequency vibrations of small amplitude, the intermediate plate being responsive to high frequency vibrations of small amplitude and the throttle orifice being automatically closeable at high pressures.

Abstract: A fluid vibration damper, such as, a shock absorber includes a cylinder and piston combination in which the piston head travels through a fluid-filled cylinder and has fluid bypass openings in its external surface forming one or more recesses of predetermined cross-sectional configurations and sizes whereby to regulate fluid flow past the piston head according to a performance curve. The bypass openings can be formed in interchangeable elements so as to permit selective variations in the fluid flow characteristics of each particular size or design of shock absorber according to a specific force performance curve.

Abstract: The invention relates to a shock absorber mounted between a suspended part and an unsuspended part of a vehicle and specifically a telescopic hydraulic shock absorber comprising a damping piston slidingly mounted in a cylinder. A compensation piston cooperates with the cylinder in order to maintain the damping piston and the cylinder in a given relative position during a variation in the load or centering of the vehicle. The compensation piston has at least one passage controlled by at least one valve sealing the passage to permit the normal operation of the shock absorber during a rapid deformation of the latter as a result of unevennesses of the road. One or more return springs maintain the damping piston at rest in a middle position relative to the cylinder facing a given zone of the latter.Application to vehicle shock absorbers.

Abstract: A shock absorber including a piston assembly dividing a cylinder into a rebound chamber and a compression chamber, the piston assembly including fluid control bleed orifices of a size to permit flow therethrough during a relatively slow long amplitude movement of the piston assembly in either direction, normally closed valves for controlling the flow of fluid between the chambers during relatively fast long amplitude movements of the piston assembly, and a normally open valve assembly operable (1) to permit relatively unrestricted flow of hydraulic fluid between the chambers during a relatively rapid short amplitude movement of the piston assembly in either direction and (2) to move into a closed position (a) during a relatively slow long amplitude movement of the piston assembly in either direction so as to permit the bleed orifices to control the resultant fluid movement between the chambers and (b) during a relatively rapid long amplitude movement so as to permit the normally closed valves to control the r

Abstract: A hydraulic braking device for a load subjected to shocks and vibrations for the stabilization of loads in thermal or nuclear generating stations.The braking device has a cylinder 1 in which there slides the piston 4 of a rod 7 bearing two flap valves 18 and 19 to brake the passage at high speed of hydraulic fluid from one chamber 15 or 16 to the other. These valves communicate with a reservoir 17, pressurized by springs 31 to 34 and accumulate the expansions of the fluid. A secondary rod 29 which has displacements with respect to rod 7 which are reduced relative to the displacement of piston of reservoir 27 with respect to this rod 7 serves as a leak indicator.Application to the stabilization of loads such as high-temperature steam conduits in thermal or nuclear generating stations.

Abstract: In a fluid displacement-type shock absorber, a piston responding to an impacting load moves within a cylinder, forcing hydraulic fluid therein out of one or more orifices into a reservoir. The resistive force of the piston depends upon its velocity, and the area of the orifice or orifices which control the rate at which the fluid can be displaced. The total available orifice are a for discharging fluid from the cylinder is progressively reduced as the piston is displaced from its initial position upon impact. The fixed orifice structure defines successive control regions, each of which is designed to provide a predetermined resistance profile and related deceleration control for a respective load system or mass system. The lightest mass system, traveling at its maximum velocity within the design range, reaches its limiting deceleration rate in the first control region.

Abstract: Hydraulic shock absorbing arrangement for pipe conduit systems including a piston slidably mounted in a liquid-filled cylinder to define spaced chambers. The piston has a rod connected thereto which is slidable in a guide positioned at one end of the cylinder. The piston rod is surrounded by a sealing bellows which is secured in a liquid-tight manner at one end to the piston and at its other end to the guide. The cylinder is mounted on a stationary bearing, while the piston rod is connected to a pipe in which shocks are to be damped. A throttling valve communicates with each cylinder chamber, the latter chambers communicating with each other through an overflow path. An expandable compensation bellows communicates with the atmosphere through an air outlet opening, but is otherwise closed.

Abstract: A vibration damper with a hydraulic damping mechanism for vehicle spring systems, in which damping valves operating by throttling the pressure medium displaced out of one working space into the other working space are interconnected between two working spaces of the hydraulic pressure medium; the two working spaces are short circuited by a by-pass connection by-passing the damping valves whereby a by-pass valve is also interconnected into the by-pass connection which operates as a function of oscillation velocity and whose valve adjusting member adjusts the by-pass connection to a narrower cross section with rising oscillation velocities.

Abstract: To prevent rapid collapse of a hydraulic lift mechanism in event of the failure of the hydraulic mechanism (e.g. as by rupture of a pressurized hydraulic line) a rate of flow responsive check valve is provided, either in a separate backup cylinder or at the inlet-outlet port of the lift cylinder, to close off the return flow path of the hydraulic line in the event of sudden depressurization of the hydraulic feed line or other pressure failure in the hydraulic liquid. In normal operation, the check valve does not oppose the return flow since the rate of such flow is insufficient to activate the valve.

Abstract: A direction reversal device including a housing and an abutment rod passing through, and movable relative to, the housing, one of the housing and the rod being stationary and the other being arranged to be impacted by a moving unit whose direction of travel is to be reversed, the device also including a resilient connection disposed between the rod and the housing and arranged to have a potential energy storage capacity corresponding to the kinetic energy possessed by the moving unit, and control elements for adjusting the storage capacity and the location of the point of direction reversal of the device.

Abstract: A weight-sensitive support assembly for an adjustable dock board of the type including a ramp with front and rear edges, with the rear edge being hingedly connected to an associated support structure so that the ramp may be swung up and down between a relatively lowered position and a relatively elevated position, the assembly comprising an elongated hollow cylinder member containing a quantity of operating fluid, a piston reciprocally disposed within the cylinder member, a piston rod member connected to the piston, connecting means operatively connecting one of the members to the ramp and the other of the members to the associated support structure, and valve means for controlling movement of the piston within the cylinder member, the valve means being responsive to a first preselected load applied to the ramp to resist movement of the piston within the cylinder member and being further responsive to a second preselected load applied to the ramp to permit movement of the piston and piston rod relative to the