GB867062A - Improved clothes washer machine - Google Patents

Abstract

867,062. Control of A.C. motors. GENERAL MOTORS CORPORATION. June 18, 1959 [June 27, 1958], No. 20899/59. Class 38 (3). A clothes-washing machine has a two-speed single-phase induction motor 16 for reciproeating an agitator or spinning a tub to which water is supplied through a thermo-responsive valve. When the tub is rotated, water is passed to a lower chamber from which it is pumped to a drain, Fig. 1 (not shown). When a timer switch 112 closes with a selector switch 51 in a low-speed position, the whole of solenoid 76 is energized through the series-connected main windings 36, 38 of the motor. This moves armature 86 to close contacts 98, 102, and open contacts 104 whereby an auxiliary motor-winding 40 is energized and the windings 36, 38 are connected in parallel to reduce the number of poles. At the same time, only a part of the solenoid 76 is included in circuit. The motor accelerates and its current decreases until the armature 86 is returned to the right and the original circuit is re-established with the main windings 36, 38, in series, the auxiliary winding 40 disconnected, and all the turns of the solenoid energized. An increase of motor current again causes the armature 86 to be moved to the left, so increasing the speed of the motor. When the selector switch 51 is adjusted to the high-speed position and the timer switch 112 closes, the main windings 36, 38 are connected in parallel and only a part of the solenoid 76 is energized. The initial surge of current through the effective turns of the solenoid moves the armature 86 to the left to energize the auxiliary winding 40, the windings 36, 38 remaining in parallel. The motor now accelerates to a predetermined speed at which the armature 86 moves to the right and disconnects the auxiliary winding. When the load on the motor increases, its speed falls and its current increases, so moving the armature 86 to the left to re-establish the circuit in which the auxiliary winding is connected. In another arrangement, the motor 130 has an auxiliary winding 132, high-speed main winding 136, and low-speed main winding 138. When the selector switch 152 is in its low-speed position and switch 112 closes, the main winding 138 and part of the solenoid 168 is energized. Armature 170 is moved to the left so that main winding 136 and auxiliary winding 132 are energized together with a part of solenoid 136. A reduction of current reestablishes the original circuit. When the selector switch is in its high-speed position, the initial circuit includes the main winding 136 and entire solenoid 168. Movement of the armature 170 to the left energizes the auxiliary winding 132 in addition to the winding 136.