Zf Friedrichshafen Ag

Karsten Kudermann

Rainer Novak

Markus Moosmann

Tobias Pfleger

A valve (V, V, V) includes a housing (VG) and a piston (VK) displaceably guided therein. A first end (VK) of the piston (VK) can be acted upon by a force, with the aid of which the piston (VK) is displaceable against a spring (F) acting upon a second end (VK) of the piston (VK). The valve (V, V, V) has four switching conditions, in which four ports (A, B, P, T) in the housing (VG) are selectively connectable to one another or blocked with respect to one another. In a first switching condition, none of the ports (A, B, P, T) are connected to one another. The spring (F) is configured in such that, in the absence of an application of force onto the first end (VK), the piston (VK) is held in a position, which corresponds to the first switching condition of the valve (V, V, V).

Valve, hydraulic system and motor vehicle gearbox

A pressure control valve () includes a pressure port (P), a consumer port (A), a tank port (T), and a piston (K) which is displaceable counter to the force of a first spring (F) and a second spring (F). The springs (F, F) and area ratios of the pressure control valve () are designed such that the pressure port (P), in the non-pressurized condition, is connected to the consumer port (A) via an opening cross-section of the pressure control valve (). An opening cross-section between the pressure port (P) and the consumer port (A) decreases depending on the pressure at the consumer port (A), and, upon attainment of a limiting pressure at the consumer port (A), the consumer port (A) is connected to the tank port (T). A related hydraulic system (HY) and a related motor vehicle transmission (G) are also provided.

Growing community of inventors

Constance, Germany

Karsten Kudermann