Abstract: A rotary connector for fluid transmission between a housing part and a shaft via rings has a bypass provided with a valve which connects the intermediate pressure space with either the leakage space or the main pressure space upon a drop in the main pressure below the pressure in the intermediate pressure space to provide inverse gap control and thereby prevent the sliding ring from pressing mechanically agains the counter-ring and generating sliding friction, heat and wear.

Abstract: A controllable two-way valve for pressure and/or flow control uses a cup-shaped piston, the bottom of which forms a large effective surface area exposed to a control flow through a slit which cooperates with an edge of the slider also serving to define the main flow cross section between an inlet and an outlet. A stationary compensating piston within this slider vents the interior of the slider and a control valve set connected to a spring chamber through which the control flow passes regulates the pressure applied to the slider in the spring compartment.

Abstract: A pump has a stator formed with intake and output ports connected to the lubricating system of an internal-combustion engine of an automotive vehicle for flow therethrough, a rotor in the stator positively driven by the engine output, an adjustment element operatively connected to the stator and rotor and displaceable between one end position corresponding to relatively great flow through the pump when the rotor is rotated by the output and an opposite end position corresponding to substantially no flow through the pump when the rotor is rotated by the engine output, and a biasing unit for urging the adjustment element toward the one end position with a fixed force. An abutment unit is connected to the adjustment element of the pump for limiting displacement of same from an intermediate position between its end positions into the opposite end position corresponding to no flow through the pump.