514,887. Centrifugal separators. BENDIX HOME APPLIANCES, INC. March 2, 1938, No. 6573. Convention date, March 6, 1937. [Class 23] [Also in Groups VIII and XXIV] In a washing and drying machine the perforated clothes receptacle is rotated unidirectionally for the washing process at a speed approximating, in revolutions per minute, to 50 times the reciprocal of the square root of the radius of the receptacle in feet whereby the wet materials are held centrifugally against the rotating receptacle until near the uppermost position thereof when they drop by gravity back into the washing liquid. After washing, a clutch is operated to throw in a high speed train for'centrifugal drying. The Specification discusses the range of speeds that is desirable and also enumerates the optimum values of the depths of washing liquid, of the clearance between the receptacle and the stationary casing, and of the dimensions of the internal lifters, and the invention is described with reference to a machine wherein the complete cycle of washing, which may include preliminary soaking, rinsing and final extraction is automatically controlled by electric circuits determined by a controller driven by an electric motor synchronously with the main motor, such control including the opening and closing of supply and discharge valves and the operation of the clutch part of the control being responsive to the action of liquid level and temperature actuated elements. The receptacle 38, Fig. 8, is supported at one end within the casing 34 by a shaft 42 carried in bearings 22, 30, in a bracket 26 extending under the casing 34 within an outer shell 16. The receptacle is partially open at its other end to receive the clothes &c. and the opening is substantially closed by a glass door 58 which may open downwards. A door 63 having side wings 69 is provided above the main door to receive charges of soap or other materials. The supply valve 66, Fig. 5, and discharge valve 96 are actuated by solenoids 68, 98, and a pump 270 and electric heater 79, Fig. 8, may be provided. The controller comprises a shaft 242, Fig. 9, which may be manually rotated to any extent from a handle 244 outside the outer shell, the handle moving over a scale marking the stage reached in the cycle. Normally the shaft is rotated slowly from a motor 214 through a cam 220, lever 222 and pawl and ratchet 228 and carries cams 250 which actuate switches 1.4, Fig. 18, controlling the circuits of the solenoids. A switch 72 is actuated by a float and in one position ensures that the heater 79 cannot be energized until the casing is full of water and in the other position ensures that the clutch cannot be operated to throw in the high speed train until the casing is empty of water. A manual switch 83 for the heating element is also provided but this is of no avail unless the switch 72 is closed. An additional switch actuated by the controller may be provided if there are independent supplies of hot and cold water, the cold inlet supply being subject also to the control of a temperature sensitive device. In one form of change speed gearing the high speed train may be thrown in when the solenoid 160 is energized. Another form of change speed gearing comprises the epicyclic arrangement shown in Fig. 11. A cone clutch 126 and a pinion 124 are keyed to the shaft 118 of the rotor of the motor 56 and the cone engages the internal periphery of an internally toothed ring 128. A carrier 130 for the planet wheels 134 is keyed to a shaft 136 which is geared to the shaft of the washing receptacle, the carrier also having a conical periphery which may engage the interior of the ring 128. The shaft is acted on by a lever 150 which is controlled by a spring 154 and the solenoid 160. When the solenoid is energized the parts are clutched together and rotate solid; when de-energized the parts move out of clutching engagement and the ring is held stationary by an externally arranged roller and wedge whereby the reduction gear becomes operative.