Abstract: A compressible liquid ride strut includes a ported piston which reciprocates in a cylinder chamber to divide the chamber into two sections. The piston ports provide controlled flow of liquid from one section to the other. A valve member engages the piston upon extreme rebound strut extension to greatly diminish flow of liquid through the piston and increase the rebound dampening rate of the strut. The valve member is acted on by a pair of springs which hold the valve member away from the piston during normal operation and permit it to move against the piston during rebound.

Abstract: A shock absorber (10) has a rebound stop assembly (22). The rebound stop assembly (22) rests upon a shoulder (30) fixed to a piston rod (16). The rebound stop assembly (22) includes an elastomeric ring (24) interposed between two collars (26 and 28) forming an annular chamber (74) therebetween. At the end of the rebound stroke of the piston rod (16), the rebound stop assembly (22) is axially compressed between the shoulder (30) of the piston rod (16) and the rod guide (18) until the elastomeric ring (24) deforms to abut the inner wall (64) of the working cylinder. As the elastomeric ring deforms, the annular chamber decreases in volume. A restrictive passage (71) allows a restrictive flow of fluid therefrom. An additional chamber (70) is formed which is in restrictive fluid communication through the passage (71) with a section (68) of a rebound chamber (20).

Abstract: A hydro-mechanical compression and rebound stop 22 for a suspension strut 10 in which a tubular sleeve 30 is coaxially mounted about a piston rod 18 and is positioned by a coil spring 26 which has its other end seated against a fixed annular seat 24. An abutment ring 50 engages the bottom end of the sleeve 30 to force the sleeve through the annular seat 24 against the bias of the spring and to cause a hydraulic restricted hydraulic flow therethrough. Upon rebound, the abutment ring 50 compresses an elastomeric sleeve 48 against a rod guide 43 at the top end of the working cylinder 12.

Abstract: In the illustrative embodiment of the invention disclosed, a pressurized gas spring is arranged to provide three different damping-rate states as the piston rod is progressively urged axially outward of the cylinder. A first damping-rate stage is provided by an axially movable ring carried by the piston structure, a second stage is provided by an axially movable sleeve member slidably mounted on the piston rod for engagement at its inner end with the piston structure, and a third stage is provided by entry of the outer end of the sleeve member into a damping cylinder mounted adjacent the end wall of the cylinder through which the piston rod extends. The three damping-rate stages act cumulatively increasingly to slow outward movement of the piston rod.

Abstract: A fluidic damping mechanism including a cylinder, a piston rod and a piston dividing the interior of the cylinder into a pair of working chambers is arranged to include within one of the working chambers a composite damping structure which imparts damping characteristics derived from the combined action of a mechanical spring mechanism and fluid throttling components.

Abstract: A pneumatic spring for use, for example, as a lifting device or support strut for a chair or the like with provision for the adjustment of axial extent. The pneumatic spring is substantially composed of a telescoping cylinder-piston assembly containing a gas and/or fluid under compression. A releasable valve assembly permits the relative position of the piston with respect to the housing to be adjusted arbitrarily. In order to provide for a terminal spring stiffening in the position of near full insertion of the piston rod, the invention provides that a pin extending from the main piston enters a central volume which is thereby sealed off from the remainder of the internal volume. Accordingly, the gas in the remaining available volume is compressed more highly and exerts an increased opposing force on the primary piston during its final insertion.

Abstract: In the illustrative embodiments described, the two compartments of the cylinder cavity of a gas spring of the piston-and-cylinder type, separated by a piston assembly, are connected by first and second passages extending across the piston. A valve arrangement on the piston assembly opens the second passage in response to movement of the piston assembly towards a terminal position in the cylinder and closes the second passage in response to movement of the piston assembly away from the terminal position. The first passage is open at all positions of the piston assembly remote from the terminal position. Releasable locking structure in the cylinder is operable to close the first passage as the piston assembly approaches the terminal position, thereby to hold the piston assembly in such terminal position until the locking force is manually overridden.

Abstract: A motor truck hood opening damper restraint in the form of a vertically mounted, hydraulic hood damper or dash pot which restricts the speed of travel of the hood past an overcenter position, cushions the hood at the stop at the open position and permits unrestricted speed of travel when closing the hood.

Abstract: A shock absorber of the hydraulic-pneumatic type includes a cylindrical casing closed at both ends and partially filled with a liquid damping medium. A piston is reciprocable in the casing, has valve controlled passages and a piston rod thereon extending outwardly through a packed opening in one of the ends. A quantity of gaseous fluid under super-atmospheric pressure occupies the space above the level of the liquid, and a perforated partition forming an anti-splash device is disposed slightly below the liquid level. The partition is stationary in the casing and is frictionally held in place against the inner surface of the casing but is displaceable under the effect of a force greater than that applied to it by the movement of the shock absorber as a whole or of the liquid damping medium upon reciprocation of the piston.

Abstract: A gas spring includes a cylinder having two axial portions of different cross section and two pistons mounted on a common piston rod and respectively matching the cross sections of the cylinder portions. The pistons are spaced on the piston rod so that they are either both in the wider cylinder portion or respectively received in the two portions. A first throttling passage permits flow of fluid between the two cylinder compartments separated by the larger piston, and a second throttling passage by-passes the smaller piston only during movement inward of the smaller cylinder portion to permit flow of fluid out of that cylinder portion. A valve arrangement is biased for sealing the two parts of the cylinder cavity separated by the smaller piston when the latter is in the smaller cylinder portion, but does not move inward of that portion. The valve arrangement responds to a sufficient, axially applied force for connecting the two cavity parts.

Abstract: A brake to decelerate the driving movement of an actuating rod along an axis. The actuating rod is driven relative to a frame by an actuating mechanism. The actuating rod has an external tapered surface whose lateral dimension decreases in the direction in which it is driven. The brake includes a case attachable to the frame which contains within it a peripheral cylindrical brake band and a wedge member. The wedge member has an outer wall, and a tapered inside wall with substantially the same taper angle as the actuating rod. The wedge member and the brake member are disposed inside a passage in the case, with the brake band disposed between the case wall and the wedge member. There is a spacing between the wall of the passage and the outer wall of the brake band. The tapered inside wall is axially aligned with at least a portion of the inside wall of the brake band.

Abstract: A gas spring comprises an annular oil cushion seal near the main seal end of the cylinder which defines an oil cushion chamber with the main seal. A flow-restricting passage through the oil cushion seal permits controlled flow of gas and oil from the rod chamber to the oil cushion chamber to provide a second phase of damping as the rod nears the fully extended position and bypass communication from the tube chamber to the rod chamber is via the damping passage in the oil cushion seal and the main damping passage which bypasses the piston, which passages are in series at the end of the operating stroke. The second stage of damping essentially eliminates oscillation of the gas spring at the end of the operating stroke.

Abstract: A door closer is connected to a door. The movements of the door cause a piston member in the door closer to pump a pressure medium through a flow duct. There is also a flow limiting member influencing at least the speed of the opening movement of the door, and this flow limiting member cooperates with an adjustable activating element which, at a desired opening moment mechanically sets the elements of the flow limiting member in a position considerably increasing the flow resistance of the pressure medium. This brakes the movement of the piston member, and thus, also the movement of the door.

Abstract: The piston in a gas spring of the piston-and-cylinder type is prevented from moving from one of its terminal positions under the pressure of the gas in the cylinder by a plunger on the piston projecting toward the closed cylinder end and received in an axial recess of a brake member on the cylinder by cooperating engagement elements on the plunger and brake member which may provide a friction fit or impede fluid flow into the recess.

Abstract: A spring device including a piston slidably disposed in an inner cylinder of a dual inner and outer cylinder with a piston rod secured thereto and extending to the outside of the cylinder through a rod guide closing one end of the inner cylinder, an oil passage formed in the rod guide and connecting an annular chamber between the inner and outer cylinders with the interior of the inner cylinder, and a device for supplying a force on the piston to project the piston rod outwardly, in which a guide member is supported on the piston rod with a coil spring interposed between the guide member and the piston, and the guide member is adapted to contact the rod guide to control the oil flowing through the oil passage when the piston rod moves outward by a predetermined amount.

Abstract: This invention is a piston-cylinder hydraulic snubbing device to arrest or resist motion. The invention may be utilized as a snubbing device alone, or it may be incorporated into a hydraulically actuated piston-cylinder assembly. The principal feature is that an orifice, through which hydraulic fluid is forced, is in the form of a gap between the ends of a piston ring, which gap is varied by engagement of the ring with a tapered bore in the cylinder.

Abstract: A hydraulic shock absorber for use in a motor vehicle suspension system to reduce dynamic tilting of the vehicle. The shock absorber is of the conventional type having a cylinder, a piston arranged to move within the cylinder between two end stops, and a pressure medium arranged within the cylinder to damp the movement of the piston. A device is provided, according to the invention, for increasing the damping of the piston motion directed away from a particular end stop only after the piston has approached closer to that end stop than is usual during normal operation of the vehicle. The particular end stop, in this case, is the one near which the piston will be located when the associated motor vehicle wheel is unloaded.

Abstract: A liquid damper comprises a piston head which slides within a cylinder and which is carried by a piston rod which slides within an annular gland at one end of the cylinder. A passage which includes a damping valve connects the annular cylinder space to a liquid reservoir so that liquid displaced from the annular cylinder space by movement of the piston in either direction is fed through the damping valve to the liquid reservoir. The liquid reservoir is connected to the other cylinder space through a non-return valve. A groove which varies in area along its length, extends partway along the piston rod.

Abstract: An improved decelerating mechanism of the dashpot type in which the piston normally leaves the cylinder on each operating cycle and has a sealing ring cantilevered in the direction of piston travel having a deep undercut whereby air pressure of the air compressed in front of the piston inside the cylinder biases the cantilevered sealing ring against the wall of the cylinder to accomplish effective sealing of the piston against uncontrolled air leakage. A projection on the front of the piston seals the air exit from the compression chamber during the last portion of piston travel in order to provide a final cushion for the moving dashpot piston.

Abstract: The improved hydraulically actuated percussion drill described hereinafter is designed to reciprocate a striker piston contained therein regardless of whether or not the striker piston engages the drill steel whereby vibration can be imparted to the drill. The drill includes an overtravel portion that cooperates with the striker piston to prevent metal-to-metal contact of the striker piston with the housing during operation. Means are provided to prevent the loss of fluid from the overtravel chamber whereby the striker piston will be returned to the upper end of its stroke and will not become stalled in the overtravel chamber.