Abstract: A method for controlling an electric motor of a vehicle pump used to deliver a medium. According to the method, a period required for at least one partial revolution of a rotor of the electric motor is determined. The fluctuations during the period can represent a measurement of the true running of the electric motor. The speed of the electric motor can be altered depending on the deviation of the period from a comparative value. As a result, the true running of the electric motor can be guaranteed once again.

Abstract: A method for controlling an electric motor of a vehicle pump used to deliver a medium. According to the method, a period required for at least one partial revolution of a rotor of the electric motor is determined. The fluctuations during the period can represent a measurement of the true running of the electric motor. The speed of the electric motor can be altered depending on the deviation of the period from a comparative value. As a result, the true running of the electric motor can be guaranteed once again.

Abstract: A modular switching system includes a transistor operative in a switching mode for applying current to a load. Adaptation of the system to accommodate different values of load is attained by coupling an input drive ,signal to a base terminal of the transistor via a variable gain amplifier wherein the gain is established by a load-adaption signal to meet the requisite base current drive signal for the load. Plural emitter terminals of the transistor connected to separate branches of a monitoring circuit, each branch having its own threshold detector, for monitoring of minimum and maximum values of load current.

Abstract: A switching system includes a module having at least one semiconductor switch for switching current to a load, in particular, a setting member in an automotive control or automatic control device. A short-circuit current monitoring circuit and an idle current monitoring circuit are provided for each semiconductor switch. Each switch may constructed as a multiple-emitter transistor with separate emitter terminals being connected to the respective monitoring circuits whereby load current in the multiple-emitter transistor can be monitored. The short-circuit monitoring circuit outputs a signal indicating excessively large load current in the transistor. The idle monitoring circuit outputs a signal indicating excessively small load current in the transistor.

Abstract: In a method for detecting the readiness for operation of a oxygen measurement probe which is arranged in the exhaust duct of an internal combustion engine and serves together with a regulating device to regulate the preparation of the mixture for the internal combustion engine, the output voltage of the oxygen measurement probe is integrated with an integration time constant which is dependent on the internal resistance of the oxygen measurement probe. The rate of change of the output voltage is measured. Above a predetermined value of the rate of change, readiness for operation is noted. In a circuit arrangement for the carrying out of the method, there is connected to the output of the oxygen measurement probe the input of an integrator whose output is connected via an analog-to-digital converter to the input of a microcomputer. Also there can be fed to an integrator an initial value which lies in a central part of the operating range of the output voltage of the integrator.