Abstract: An electronically commutated internal rotor motor (20) has an outer stator (28) and a permanent magnet rotor (36) arranged rotatably therein by means of a shaft (40) supported at its drive end (42) by a rotary bearing (54) located in the A-side bell (26) and supported at its other end (44) by a rotary bearing (72) located in the B-side bell (66). The rotary bearing (54) in the A-side bell is preferably so configured that it permits a small radial movement (56) of the drive end (42) relative to this bell (26). The rotary bearing (72) in the B-side bell (66) has its outer race (72) tensioned against a shoulder (90, 94). Its inner race (74) is tensioned between a shoulder (78) of the shaft (40) and a shaped part of non-ferromagnetic material. This shaped part is pressed by a countersunk screw (82), screwed into a threaded bore (84) of the other shaft end (44), against the inner race.

Abstract: A motor, suitable for driving a fan, features a plain bearing (36) that contains ferromagnetic material and serves for radial support of a rotor shaft (34) made of ferromagnetic material. The shaft (34) is arranged rotatably and axially displaceably in that plain bearing (36), and has a free end (35). Provided at the free end is a thrust bearing which has a dome-shaped end (66) provided at that free end (35), and a contact member (68, 69), coacting with the latter dome, the contact member being made at least partially of ferromagnetic material. Also provided is at least one permanent magnet (72) in order to form a magnetic circuit (82) from a first magnet pole (74) via the plain bearing (36), the free shaft end (35) and its dome-shaped end (66), and the contact member (68) to the other magnet pole (76), and thereby to bring about a defined magnetic attractive force between the dome-shaped end (66) and the contact member (68).

Abstract: An electronically commutated internal rotor motor (20) has an outer stator (28) and a permanent magnet rotor (36) arranged rotatably therein by means of a shaft (40) supported at its drive end (42) by a rotary bearing (54) located in the A-side bell (26) and supported at its other end (44) by a rotary bearing (72) located in the B-side bell (66). The rotary bearing (54) in the A-side bell is preferably so configured that it permits a small radial movement (56) of the drive end (42) relative to this bell (26). The rotary bearing (72) in the B-side bell (66) has its outer race (72) tensioned against a shoulder (90, 94). Its inner race (74) is tensioned between a shoulder (78) of the shaft (40) and a shaped part of non-ferromagnetic material. This shaped part is pressed by a countersunk screw (82), screwed into a threaded bore (84) of the other shaft end (44), against the inner race.

Abstract: The invention concerns an arrangement comprising a plain bearing (36) that contains ferromagnetic material and serves for radial support of a shaft (34) made of ferromagnetic material. The shaft (34) is arranged rotatably and axially displaceably in that plain bearing (36), and has a free end (35). Provided at the latter is a step bearing which has a bearing dome (66) provided at that free end (35), and a contact member (68, 69), coacting with the latter dome, said contact member being made at least partially of ferromagnetic material.

Abstract: Drive circuit for a brushless, electronically commutated DC motor, wherein an electronic switching element (T.sub.1, T.sub.2) is arranged in series with each phase winding (L.sub.1, L.sub.2) of the motor and the switching elements (T.sub.1, T.sub.2) are driven in response to a sensor (2) for the rotational position of the rotor, in particular formed as a digital Hall IC, wherein each phase winding (L.sub.1, L.sub.2) is connected to a common node (8) of the circuit via a respective decoupling diode (D.sub.1, D.sub.2), and wherein parallel to the phase windings (L.sub.1, L.sub.2) and the corresponding decoupling diodes (D.sub.1, D.sub.2) a protective transistor circuit (10) is arranged that is driven in such a manner that the inductively induced voltage peaks are eliminated.

Abstract: The present invention concerns a switched mode power supply with a timed switching regulator (1), whereby an electronic switching component (T.sub.1) is periodically switched on and off in such a particular pulse duty ratio, that an output control voltage (U.sub.B) is produced from a rectified input voltage (U.sub.E) across a storage circuit (2) with a smoothing choke (L), an intermediate circuit memory backup capacitor (C.sub.Z), and a free-wheeling diode (D.sub.F). The switching component (T.sub.1) is composed of a transistor, namely an FET or an IGBT, whose base or gate (G) is preconnected to a special control circuit (4) in such a way that an increased trigger current briefly flows in the trigger circuit for gating, and a substantially smaller holding current subsequently flows in the gated state, respectively.

Abstract: An improved power supply for converting any of various standard national AC network voltages to low-voltage DC power suitable for driving a 1 or 2-watt device, such as a fan, features a semiconductor control circuit (18, FET 46) which chops each half-wave of a rectified voltage and uses the low-voltage portions to feed charging current pulses to a storage capacitor. The voltage on the capacitor (14) is used by other portions of the circuit to regulate rotation speed of the fan or other consuming device (40) to a value set on a variable resistor. The use of the low-voltage portions of the input signal reduces power losses and increases efficiency.

Abstract: A circuit arrangement for generating a useful direct voltage signal associated with the frequency of an alternating current signal serves, in particular, to regulate the synchronism of an electric motor. It includes a comparator circuit (7) which converts the two opposite polarity half-waves of the alternating current signal of a tacho coil (2) into pulses whose edges trigger a measuring and control circuit (18) which generates direct voltages corresponding to the half-period durations of the alternating current signal measured from the respective zero passages.

Abstract: A circuit arrangement for generating a useful direct voltage signal associated with the frequency of an alternating current signal serves, in particular, to regulate the synchronism of an electric motor. It includes a comparator circuit (7) which converts the two opposite polarity halfwaves of the alternating current signal of a tacho coil (2) into pulses whose edges trigger a measuring and control circuit (18) which generates direct voltages corresponding to the half-period durations of the alternating current signal measured from the respective zero passages.

Abstract: When the motor's permanent-magnet rotor is in a first range of angular positions a stator-winding phase is energized to have a first magnetic polarity, and to have an opposite second polarity when the rotor is in a second range of angular positions. The rotor angular position is sensed by a magnetic-field-sensitive semiconductor element, especially a Hall generator, responsive to the field from the permanent-magnet rotor. When the rotor is in a range of angular positions between such first and second ranges, all power transistors are rendered non-conductive, by control signals derived from the magnetic-field-sensitive semiconductor element by intermediate circuitry, to render the stator-winding phase currentless during the time interval within which commutation is to occur.

Abstract: A commutatorless DC motor with an armature, a detector for sensing the position of the armature, a motor winding arrangement for supplying current via a bridge network, the network being controlled by semiconductor switches that act in dependence upon the armature position.

Abstract: A method and device are provided for substantially reducing the effect of a low frequency varying torque resulting from a characteristic asymmetric switching of a magnetic flux-sensitive control member when the control member is used to sense the rotating position of a rotor in a brushless d.c. motor.

Abstract: An improvement is disclosed in which a circuit utilizes the internal resistance or bulk resistance of a Hall generator in connection with an amplifier having a feedback resistance which is less or larger than the internal resistance or bulk resistance of the Hall generator. By utilizing this improvement, changes in output voltage of the Hall generator caused by variations in temperature and spread in characteristics can be at least partially compensated.

Abstract: A network controlled inlet is provided for current sensing in a comparator to control the current in direct current motors. An electrical signal generated from a physical parameter is conducted to the first input of the comparator and a signal characterizing the speed of the motor is conducted to the second inlet of the comparator.

Abstract: In response to a Hall-IC sensor exposed to the magnetic field of the rotor of a brushless d.c. motor, two interleaved sequences of pulses are generated at separate outputs with an interpulse pause of a certain length occurring between successive interleaved pulses to prevent reduction of efficiency and increase of motor noise that would result from overlapping pulses being supplied to the stator of the motor. When these pulses are utilized to switch a semiconductor full bridge circuit, through which a single winding of the stator is energized by current pulses alternating in direction, prevention of short-circuits resulting from slow turn-off of the semiconductor switches is prevented. For overcurrent protection, only half of the bridge is intermittently blocked by a current regulator when the current reaches a predetermined limiting value, this provision also reducing generation of noise and interference by the motor.

Abstract: An evaluation circuit, sensitive of the frequency of an applied signal, is connected to the motor to sense the a-c component of the pulsating current flow through the motor, the evaluation circuit preferably including a filter matched to the frequency of the a-c component at operating speed to enhance the a-c component at operating speed or speed range with respect to other frequencies. The signal is taken across an impedance element connected in series with the motor and motor supply circuit, which may be a transformer or a low-value resistor, to provide an output voltage signal of a magnitude sufficient to unambiguously control a transistor amplifier, for example in the order of 0.1 V.

Abstract: A brushless d.c. motor comprises a stator having stator winding means thereon, a permanent magnet rotor rotatable relative to the stator and a rotor position-dependent semiconductor commutating means coupled to the stator winding means for controlling the currents in the stator winding means. Further provided is means including amplifying means responsive to the outputs of the control means for reducing the currents in the stator winding means at predetermined rotor position ranges to substantially zero. The semiconductor control means is preferably a Hall generator.