Siemens Aktiengesellschaft

Hans Kuhnlein

Georg Kogler

Karl Schalk

Manfred Liska

Hermann Ebert

Reinhard Stark

Johann Gruntleitner

Hans Gruntleitner

A calorimeter for the measurement of a quantity of heat given up by a fluidic medium in at least one heat exchanger, with an impellerless flow velocity measuring device as well as temperature sensors for determining the forward flow-return flow temperature difference, including a multiplier for forming the product from the flow velocity and the forward flow-return flow temperature difference; and also a quantizer for the formation of a pulse train having a frequency which is proportional to the product, as well as a cumulative counting device for the pulses of the pulse train connected to the output thereof. The flow velocity measuring device is activated only at predetermined points in time or moments, whereby the frequency of these measuring moments is determined approximately proportional to an auxiliary variable which represents a measure for the importance of a possible change in a parameter determining the heating quantities on the measured result, and in which a second multiplier is connected ahead of the quantizer which the output signal of the first multiplier is multiplied with a value proportional to the timewise interval between two measurement switching moments.

Calorimeter

A brushless D-C motor of the type having a permanent magnet rotor, a plurality of individual stator windings which are disposed 90.degree. apart with respect to each other, and at least two Hall-effect galvanomagnetic transducers which are disposed 90.degree. apart with respect to each other, and within the air gap of the motor. The galvanomagnetic transducers produce control signals in response to the angular position of the rotor for controlling the conductive states of semiconductive switching devices which are each electrically disposed in series with respective individual stator windings, and a controlled current generator which controls the current flowing through the stator windings so as to conform with a sinusoidal wave shape.

Brushless D-C motor

In a control signal transmitter for the commutating device of an electronically commutated motor, which contains at least two rotor position transmitters, particularly Hall effect generators, and an evaluation circuit which derives control signals for the commutating device from the output signals of the rotor position transmitters which determine the individual switching instants for the switching elements of the commutating device, in order to permit operation with a higher number of pulses, the evaluation circuit also includes a logic circuit to which the output signals of the rotor position transmitters are fed which circuit furnishes further control signals for the commutating device.

Control signal transmitter for the commutating device of an

The polarity of the desired speed voltage of a speed control device and the commutation sequence of the current flowing in the stator windings are reversed for reversing an electronically commutated D.C. motor. A voltage, proportional to the EMF ad obtained from the motor voltage by I.times.R compensation, is used as the actual speed voltage for the speed control device, the polarity of the voltage proportional to the EMF being reversed when the direction of rotation signal changes.

Reversible direct current motor with a permanent magnet rotor and

An electronic motor has a multi-pole external rotor and a multi-slot stator which is rotatable inside the external rotor. At least two magnetic field sensing elements are arranged in the vicinity of the external rotor and current supply to the stator windings is provided by a commutation device. The prior art stator was provided with obliquely set stator winding slots and involved a complicated winding technique. To eliminate this disadvantage and to be able to use slots lying parallel to the axis, the neutral field lines between each north and south pole of the external rotor are made to lie parallel to the rotor axis in the region of the magnetic field sensing elements and obliquely thereto in the region of the laminated rotor stack.

Electronic motor having a multi-pole external rotor

In a D.C. motor in which signals generated by an angular position transmitter control the commutation of the current flowing through the stator winding via a selection circuit containing Exclusive OR gates by means of which the polarity of the signals generated by the angular position transmitters can be reversed for the reversal of the direction of rotation, operating modes of 'Operation' and 'Braking' can be specified with only one command input for the Exclusive OR gates using an additional Exclusive OR gate.

Direct current motor with polyphase stator winding and electronic

A commutation device for controlling a brushless d-c motor is disclosed. The commutation device includes a regulator circuit for regulating current supplied to the motor by means of a transistor connected between the power source and a commutation circuit. A threshold hysteresis level detector controls the transistor. During current peaks generated in the commutation circuit, the hysteresis of the level detector is increased to provide stable operation of the regulator with different motors and operating voltages.

Control arrangement for a brushless D-C motor

In a position control device for driving a speed controlled motor, the motor having coupled thereto a tachometer generator for providing velocity feedback, a brushless tachometer generator having at least one position transmitter for the rotor thereof is used as the tachometer generator and the position signals of the position transmitter also used to provide an actual value feedback for the position control.

Position control device

This invention is for apparatus used in combination with electronic commutation circuitry for a D.C. motor with a Y-connected stator winding wherein current control is accomplished by means of a cyclic current regulator. Current to the regulator is applied to the regulator by means of a series connected choke inductor and resistor, across which is connected in parallel a by-pass diode.

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Nurnberg-Grossgrundlach, Germany

Hans Kuhnlein