ARRANGEMENT FOR SENSING THE TEMPERATURE OF THE ARMATURE OF A DIRECT CURRENT MOTOR

PCT No. PCT/DE97/01166 Sec. 371 Date May 27, 1998 Sec. 102(e) Date May 27, 1998 PCT Filed Jun. 10, 1997 PCT Pub. No. WO98/04893 PCT Pub. Date Feb. 5, 1998An arrangement for the determination of the temperature of a direct-current motor. The temperature is determined in an indirect manner from the temperature-dependent armature resistance, with the armature resistance being determined as the quotient of the voltage being applied to and measured at the motor terminals and of the blocking current of the armature, and being set in relation to the respective temperature. The current signal determined from the current flowing within the armature is averaged with adjustable, calculated integration times with the aid of an integrator that can be controlled by a microcontroller. The arrangement, can be used for the indirect determination of the rpm rate (N) and/or variations that are critical or of interest in the rpm rate of the motor. The rpm rate is proportional to the voltage (Uind) induced within the armature, taking into consideration a motor-typical proportionality constant ( kappa ) according to equation N= kappa Uind, with the voltage induced within the armature being determined as the difference between the voltage being applied to the motor terminals and the product of armature current and armature resistance.