Abstract: A pressure regulating valve has a valve chamber having an inlet for connecting to a pressure source, a discharge chamber communicating through a valve opening with the valve chamber, a valve member, a valve seat surrounding the valve opening, a valve closing spring which presses the valve member against the valve seat with an adjustable spring force, and a throttling surface arranged downstream of the valve opening so that between the valve member and an inner wall of the discharge chamber, a pressure is formed at the valve member which counteracts the spring force.

Abstract: Aggregate for feeding fuel from a supply tank to an internal combustion engine of a motor vehicle has a feeding pump formed as a flow pump and including a disc-shaped rotatable impeller. A hydraulic buffer is formed between the impeller and the end walls of the pump chamber and includes recesses provided in a structure selected from the axial end surface of the impeller and the end walls of the pump chamber, so that the recesses are fillable with fuel during operation of the feeding pump and form the hydraulic buffer which acts in an axial direction of the impeller and stabilizes the impeller. An outer ring which connects the vanes of the impeller at their radially outer ends and limits the impeller in a peripheral direction. The recesses are arranged in a region of the outer ring.

Abstract: A fuel pump has a pump housing, and a rotor rotatable in the pump housing and having an outer surface. The housing has an inner wall which faces the rotor and forms with the outer surface of the rotor a narrow gap. The inner wall is provided with a plurality of depressions which are independent from one another and form a sealing region.

Abstract: A unit for delivery of fuel from the fuel tank to the internal combustion engine of a motor vehicle includes a feed pump which is arranged in the fuel tank and constructed as a flow pump with substantially circular-cylindrical impeller driven in rotation in a correspondingly circular-cylindrical pump chamber. In at least one of the two chamber end walls, at least one approximately annular delivery duct which is groove-like in cross section extends from a suction opening which opens into the pump chamber to a pressure opening leading out of the latter. This end wall of the chamber is penetrated in the region of the pressure opening by a bore hole connecting the pump chamber with a region of the system in which low pressure prevails.