摘要:
A control apparatus and method for an electric motor having sensing devices which sense the frequency and polarity of EMFs in the rotor windings down to a condition where the rotor is in condition for reversing, and causing reversing of the motor when the frequency is such as to allow reversing and the polarits polarity of a selected winding is at or near a zero crossing between positive and negative polarities. Cyclical reversal is effected by measuring the time the rotor takes to coast from a “power off” condition to the condition for reversing and with an electronically commutated motor reversing can usually be effected in one commutation period. The motor is used in a clothes washing machine or similar application where rapid reversal is required or timing of the time from one reversal to the next is required to be constant.
摘要:
A control apparatus and method for an electric motor having sensing devices which sense the frequency and polarity of EMFs in the rotor windings down to a condition where the rotor is in condition for reversing, and causing reversing of the motor when the frequency is such as to allow reversing and the polarits of a selected winding is at or near a zero crossing between positive and negative polarities. Cyclical reversal is effected by measuring the time the rotor takes to coast from a "power off" condition to the condition for reversing and with an electronically commutated motor reversing can usually be effected in one commutation period. The motor is used in a clothes washing machine or similar application where rapid reversal is required or timing of the time from one reversal to the next is required to be constant.
摘要:
An electric motor (2) for a clothes washing machine including the motor and a drive, the motor having a stator (25) held outboard of a frame carrying bearings (37, 38) in which a shaft (11) rotates, the shaft carrying the rotor (21) outboard of the stator (25), and permanent magnets (17) on an inner face of the rotor. The stator (25) is formed as an annular helical yoke edgewise wound from a strip of magnetic material and having an inner face and an outer face, the strip having pole pieces (8) formed integrally therewith extending from one edge of the strip and the strip being edgewise wound whereby the pole pieces coincide in stacked groups to form a plurality of poles arranged at equally spaced intervals extending radially outwardly from the outer face of the yoke. Energizable stator windings (26) are wound directly on the poles (8) of the stator and are adapted to be energized through an electronic commutation circuit (65,66) and the rotor (21) is mounted for rotation exteriorly of and relative to the stator, the rotor comprising a backing ring (16) of magnetic material and a series of permanent magnets (17) held at spaced-apart intervals on an inner surface of the backing ring (16) and opposing the poles (8) of the stator (25).
摘要:
An electric motor (2) for a clothes washing machine including the motor and a drive, the motor having a stator (25) held outboard of a frame carrying bearings (37, 38) in which a shaft (11) rotates, the shaft carrying the rotor (21) outboard of the stator (25), and permanent magnets (17) on an inner face of the rotor. The stator (25) is formed as an annular helical yoke edgewise wound from a strip of magnetic material and having an inner face and an outer face, the strip having pole pieces (8) formed integrally therewith extending from one edge of the strip and the strip being edgewise wound whereby the pole pieces coincide in stacked groups to form a plurality of poles arranged at equally spaced intervals extending radially outwardly from the outer face of the yoke. Energizable stator windings (26) are wound directly on the poles (8) of the stator and are adapted to be energized through an electronic commutation circuit (65,66) and the rotor (21) is mounted for rotation exteriorly of and relative to the stator, the rotor comprising a backing ring (16) of magnetic material and a series of permanent magnets (17) held at spaced-apart intervals on an inner surface of the backing ring (16) and opposing the poles (8) of the stator (25).
摘要:
An electric motor, a drive and a clothes washing machine including the motor and drive, the motor having a stator held outboard of a frame carrying bearings in which a shaft rotates, the shaft carrying the rotor outboard of the stator, the rotor having permanent magnets on an inner face thereof. The shaft carries an agitator and a spin tub of the clothes washing machine, and interconnecting members between a part rotatable with the agitator and a part rotatable with the spin tub are movable axially on the shaft relative to each other by a buoyancy system which is operated by the absence or presence of water in a container of the clothes washing machine to connect the spin tub and the agitator, to be driven by the shaft continuously in one direction for spinning clothes when water is at a low level in or absent from the container, and to disconnect the spin tub from the shaft, leaving the agitator still connected to the shaft when sufficient water is in the container so that rotation of the shaft backwards and forwards by the motor washes clothes in the spin tub by backwards and forwards movement of the agitator.
摘要:
An electric motor, a drive and a clothes washing machine including the motor and drive are described, the motor having a stator held outboard of a frame carrying bearings in which a shaft rotates, the shaft carrying the rotor outboard of the stator, the rotor having permanent magnets on an inner face thereof. The shaft carries an agitator and a spin tub of the clothes washing machine and interconnecting members between a part rotatable with the agitator and a part rotatable with the spin tub are movable axially on the shaft relative to each other by a buoyancy system which is operated by the absence or presence of water in a container of the clothes washing machine to connect the spin tub and the agitator to be driven by the shaft continuously in one direction for spinning clothes when water is at a low level in or absent from the container and to disconnect the spin tub from the shaft, leaving the agitator still connected to the shaft when sufficient water is in the container so that rotation of the shaft backwards and forwards by the motor washes clothes in the spin tub by backwards and forwards movement of the agitator.