Abstract: Self-pumping hydropneumatic suspension strut unit with internal level control, with an oil-filled working cylinder subject to the pressure of gas cushions and with a damping piston, which is free to slide inside the cylinder and is mounted at the end of a hollow piston rod, the cavity of which serves as a pump cylinder for a pump rod attached to the working cylinder. Oil is drawn from a reservoir space when the piston rod travels outward, whereas the oil is conveyed into the working space when the piston rod travels inward. The pump rod passes through the end wall of the working space and is held axially in position by an end-mounted disk formed as a Belleville washer, which acts as a universal joint for the rod. The disk engages in a groove in the pump rod and is held in place by its outer circumference axially between the working cylinder and the end wall of the working cylinder.

Abstract: Self-pumping hydropneumatic suspension strut unit with internal level control, with an oil-filled working cylinder subject to the pressure of gas cushions and with a damping piston, which is free to slide inside the cylinder and is mounted at the end of a hollow piston rod, the cavity of which serves as a pump cylinder for a pump rod attached to the working cylinder. Oil is drawn from a reservoir space when the piston rod travels outward, whereas the oil is conveyed into the working space when the piston rod travels inward. The pump rod passes through the end wall of the working space and is held axially in position by an end-mounted disk, which acts as a universal joint for the rod, and the disk engages in a groove in the pump rod and is held in place by its outer circumference axially between the working cylinder and the end wall of the working cylinder.

Abstract: Guide for the piston rod of a piston-cylinder assembly, especially for a vibration damper, a shock-absorbing strut, or a level-control device. The guide has a guide body with an outer end surface holding a piston rod seal, where the piston rod is installed in the guide and sealed with freedom to move in the axial direction. The piston rod seal has an axial extension opposite the piston-cylinder assembly, which extension is held in an annular recess in the end surface, which recess is spaced from the piston rod and coaxial to the piston rod.

Abstract: Guide for the piston rod of a piston-cylinder assembly, especially for a vibration damper, a shock-absorbing strut, or a level-control element, where the guide body holds the cylinder tube and the outside tube and simultaneously centers the piston rod in a central bore. The guide body has two axially spaced sealing elements which rest on the outside surface of the piston rod and seal off the interior space of the piston-cylinder assembly from the atmosphere. A flow connection, starting from the area of the intermediate space between the seals, extends to the interior space and is provided with a nonreturn valve, through which a flow can proceed only in the direction of the interior space.

Abstract: Guide for the piston rod of a piston-cylinder assembly, especially for a vibration damper, a shock-absorbing strut, or a level-control device. The guide has a guide body with an outer end surface holding a piston rod seal, where the piston rod is installed in the guide and sealed with freedom to move in the axial direction. The piston rod seal has an axial extension opposite the piston-cylinder assembly, which extension is held in an annular recess in the end surface, which recess is spaced from the piston rod and coaxial to the piston rod.

Abstract: Guide for the piston rod of a piston-cylinder assembly, especially for a vibration damper, a shock-absorbing strut, or a level-control element, where the guide body holds the cylinder tube and the outside tube and simultaneously centers the piston rod in a central bore. The guide body has two axially spaced sealing elements which rest on the outside surface of the piston rod and seal off the interior space of the piston-cylinder assembly from the atmosphere. A flow connection, starting from the area of the intermediate space between the seals, extends to the interior space and is provided with a nonreturn valve, through which a flow can proceed only in the direction of the interior space.

Abstract: A spring strut having a delayed bleed. The spring strut includes a non-return valve arranged parallel to the throttle such that the flow of oil can pass through the non-return valve from the low-pressure chamber in the direction of the pump cylinder.

Abstract: A piston cylinder assembly which includes a work cylinder, a piston and a piston rod, which piston rod carries the piston and extends out of the work cylinder in a sealed manner, as well as a ring-shaped equalization chamber formed by two tubes is disclosed. The equalization chamber is divided by a separating piston into two partial chambers, the separating piston having two parts which are guided so that they can move in a sealed manner axially on the wall of the respective tube of the compensation chamber facing the respective part. The two parts of the separating piston are connected by a flexible portion allowing them to move radially with respect to one another and are sealed with respect to one another.

Abstract: An impact damper which is equipped with an economical, cost-effective work piston, on which not only can a weight reduction be made, but also a substantial simplification in manufacture can be achieved. This impact damper is also designed to be deformable instantaneously upon collision with an obstacle when the force of the collision exceeds a predetermined range. The work piston is designed as a tubular body closed on a side facing a fluid containing chamber, and is provided with a breaking or buckling point, whereby energies can readily be absorbed, even at relatively high impact velocities.

Abstract: A simple, operationally reliable and not-overly-sensitive level control in a generally known form of self-pumping hydropneumatic spring leg or strut is of such a construction that a delayed adjust-down control action can be achieved when a control opening is opened upon reaching a certain level. For that purpose, a sleeve is fitted as or as part of a throttle arrangement between the control opening of a hollow pump rod and a suction valve arranged at the end of the pump rod, the sleeve allowing oil to flow with a delay from the high pressure chamber which controls the level, by way of the control opening of the pump rod to the pump rod bore, the bore communicating with a low pressure chamber from which oil is normally pumped to the high pressure chamber. By removing the throttling responsibility from the control opening, size restrictions on the control opening are removed, thus facilitating sizing the control opening so as to preclude clogging.