Abstract: The invention concerns a cooling system, in particular a motor vehicle cooling system comprising a cooling circuit, in which a cooling medium is circulated by means of a cooling medium pump; wherein the cooling medium pump or another work machine is driven by means of a drive machine via a hydrodynamic coupling, comprising a pump impeller driven by the drive machine and a turbine wheel driving the cooling medium pump, which together form a toroidal working chamber which can optionally be filled with working medium; wherein the working medium is the cooling medium; a compensating container, comprising a space filled with cooling medium and an air chamber above a cooling medium level in the space filled with cooling medium. The invention is characterised in that the working chamber of the hydrodynamic coupling is always connected to the air chamber or can optionally be connected to the latter via an air-conducting connection.

Abstract: In a process and a device for measuring the rate of rotation of a rotating part which is completely enclosed by a housing, the current signal which is generated by the rotating part is subjected to two Fourier transforms after corresponding signal processing in digital form. The rate of rotation is determined from the spectrum obtained after the second Fourier transform. The rate of rotation is determined from the time pertaining to the maximum of the spectrum which is directly proportional to the rate of rotation.

Abstract: A device for supplying fuel from a supply tank to an internal combustion engine of a motor vehicle, has a pump chamber with end-side chamber walls and also having an inlet opening and an outlet opening, a drive motor, a supply pump having an impeller driven by the drive motor. The impeller rotates in the pump chamber and has a substantially disc-shaped hub part provided on its periphery with a plurality of radially outwardly extending vanes. At least one of the chamber walls in the region of radially outer ends of the vanes has an approximately ring shaped, groove-like supply passage which surrounds a rotary axis of the impeller. The inlet opening opens in a ring region of the pump chamber which is limited on one side by the hub part of the impeller and on the other side by an inner ring edge of the ring-shaped supply passage which surrounds the hub part with a distance from the latter.

Abstract: An aggregate for feeding fuel from a supply tank to the internal combustion engine of a motor vehicle, has a pump chamber with a suction opening for receiving fuel and a pressure opening for supplying a fuel and a feeding element rotating in the pump chamber and feeding fuel from the suction opening to the pressure opening. At least one of the chamber end walls in a region of a sealing surface formed between an end surface of the feeding element and one of the chamber walls has an opening which leads to an unloading space, and the opening as considered in a rotary direction of the feeding element is located near one edge which limits the suction opening, and has a radial extension which is at least equal to a radial extension of the suction opening.