Zf Friedrichshafen Ag

Klaus Schmitz

Hubert Beck

Johannes Weber

Holger Beck

Sven Kapell

Klaus Peter Klein

Peter Kirschbaum

Roland Krupp

Andre Patzenhauer

Frank Wagenknecht

Gerhard Boll

A damping valve having a damping valve body with at least one flow channel for damping medium. A valve rod is arranged in the flow channel. The valve rod cooperates with a valve disk and a valve seat surface. The valve rod carries a further valve disk that cooperates with a second valve seat surface. The first valve disk together with the first valve seat surface forms a first partial valve having a first permanently open pilot orifice cross section, and the second valve disk together with the second valve seat surface forms a second partial valve having a second pilot orifice cross section, and a shuttle valve is formed which opens one partial valve and closes the other partial valve depending on the flow direction.

Damping valve for a vibration damper

A damping valve includes a valve body with a stepped opening for receiving a preloading spring which acts on a tension rod at which is arranged a valve disk which at least partially closes a flow-out orifice of a flow channel which connects two opposite valve body sides to one another, and, in addition to the preloading spring force, a damping force which counteracts a swiveling movement of the valve disk acts on the tension rod. The additional damping force is formed by a displacer on the tension rod side. The display together with a portion of the stepped opening, forms a restrictor chamber.

Damping valve

A check valve includes a housing, a bore, and a liftably movable valve body which is spring-loaded at least after a small axial travel of the valve body and tightly contacts a valve seat. The bore is constructed as a stepped bore, the bore section of smaller diameter having the valve seat, and the bore section of larger diameter receiving the liftably movable valve member. A ball which is held captive by a holding element arranged in the bore is provided as valve body. The valve seat has a contour corresponding to the valve body in the area of the contact surface of the valve body.

Method of manufacturing a check valve

An oil-filled working cylinder is divided into first and second working spaces by a working piston, the first working space being connected to a high pressure chamber. A piston pump includes a pump rod received in a pump cylinder formed by the hollow piston rod, the pump rod having a bore connected to a low pressure chamber via a discharge valve, a distal end provided with a suction valve, and a down-regulating opening connecting the bore to the first working space as a function of the position of the working piston, the pump cylinder being connected to the first working space by an outlet valve. At least one of the valves is a check valve including a housing having a bore, a ball reciprocably guided in the bore by guide ribs, and a resilient retaining element capturing the ball in the bore and spring-loading the ball toward a valve seat.

Self-pumping hydropneumatic spring strut with internal level control

Self-pumping hydropneumatic shock absorber with internal level control, with an oil-filled working cylinder under the pressure of gas cushions and with a damping piston, which is attached to the end of a hollow piston rod and can slide back and forth in the working cylinder, the hollow space in the piston rod serving as the pump space of a pump rod attached to the working cylinder. Oil is drawn from a reservoir space when the piston rod travels outward and into the working space when the piston rod travels inward, and where a control opening is provided in the pump rod to compensate for pressure differences between the working spaces. At least one throttle acting as a function of pressure is provided in the pump space between the high-pressure gas cushion and the low-pressure gas cushion.

Self-pumping hydropneumatic shock absorber

Piston-cylinder unit including a working cylinder; a piston attached to a piston rod and installed with freedom of axial displacement in the working cylinder; and fastening elements, at least one of which is screwed into a threaded bore in the piston rod, where the interior pressure in the working cylinder holds a valve in the bore of the piston rod against an end surface of the fastening element. A vent groove leading to the atmosphere is provided between the end surface and the valve to create a pressure gradient to the working space, the groove being provided between the inner surface of the piston rod and the fastening element.

Growing community of inventors

Eitorf, Germany

Klaus Schmitz