Patent GB-632703-A (GB)
Title: Improved clothes washing and drying machine
IPC: D06F23/04
Filed: 1946-04-25
Abstract: 632,703. Clothes washing and drying machines. KIRBY, J. B. April 25, 1946, No. 30258/48. Convention date, Oct. 2, 1945. Divided out of 632,646, under which a Specification was laid open to inspection under Sect. 91 of the Acts, April 25, 1946. [Class 138 (ii)] [Also in.Group II] In a clothes washing machine having a clothes receptacle which is rotated at a comparatively high speed for centrifuging, vibration-responsive means are provided to retard the acceleration of the receptacle, whereby the clothes are subjected to a preliminary centrifuge at an intermediate speed if the clothes and receptacle are out of balance. The acceleration of the receptacle is retarded by means of a brake which is applied for a predetermined period of time, application of the brake being initiated by the vibrationresponsive means. General arrangement. - The machine comprises a square outer casing 21, Figs. 1 and 7, with transparent lid 34 and an inner circular tub 30 which contains the washing liquid and the clothes receptacle 23. The receptacle is mounted on a tubular support 55 carried by four legs 57 which also support the motor 24, which, as shown in Fig. 7, drives by belt 93 the clothes receptacle and the pump 158. The pump may be used to drain the washer or to circulate the washing liquid continuously from the bottom of the tub 30 into the top of the clothes receptacle from which it drains down, and means are provided for maintaining a constant level of water in the tub 30. The clothes receptacle is subjected to a gyrating movement during washing by holding it against rotation by means of a brake whilst its inclined axis 43 is rotated about the central vertical axis at about 600 r.p.m. Upon release of the brake, the torque applied to the bearing about which the receptacle gyrates causes the receptacle to rotate and when it attains a certain speed a centrifugal clutch causes it to be rotated at the full 600 r.p.m. Should excessive vibration occur, a vibration-sensitive switch is closed momentarily to apply a brake to the receptacle so that its rotational speed is decreased somewhat and the gyrating motion correspondingly increased, the brake being held on for a short time by a delay device. Alternative means for checking undue vibration consist in mounting the whole mechanism within the outer casing so that it is free to vibrate within limits, excessive vibration causing a rotating member to contact a stationary brake device to diminish the rotational speed. The sequence of operations is controlled by a series of cam-operated switches 225 mounted on a shaft which is driven by a small motor and which may be advanced manually by the control knob 27. A transparent anti-splash shield 274 may be provided above the clothes receptacle and a lamp 238 may be provided to illuminate the shield and the control knob dial. The bottom of the shield 274 may be connected to the top of the clothes receptacle by a flexible rubber band. Clothes receptacle driving arrangements.- The clothes receptacle 23 is rotatably mounted about an inclined axis 43, Figs. 1 and 2, by a ball-race 68 on the member 67, which is in turn rotatably mounted by ball-bearing 61 about a vertical axis, the outer race of bearing 61 being fixed to the stationary column 55. The column 55 is supported by four legs 57 terminating in adjustable feet 39, one of which, 39<SP>1</SP>, may be spring-loaded and hydraulically damped, resting in cups 239 spaced apart by a web 241. The member 67 is driven from the tubular shaft 58, pulley 94 and belt by the motor 24. The member 74 which carries the clothes receptacle and which is fixed to the inner race of bearing 68 is provided with a spherical socket and diametrical slot to receive a pin and ball fast with central shaft 59, whose lower end carries a brake drum 97. The contractible brake band 98 is normally held on, whereby the control shaft 59 and the clothes receptacle are prevented from rotating, so that the motor drive rotates the member 67 and causes the clothes container to gyrate, its inclined axis 43 gyrating around the central vertical axis at about 600 r.p.m. The dimensions of the receptacle and speed of gyration are such that the floor of the receptacle accelerates upwards and downwards faster than the acceleration of gravity. When the brake 98 is released to free the control shaft 59 the clothes receptacle commences to rotate and its rate of gyration correspondingly falls. When the receptacle reaches a certain speed of rotation, a centrifugal clutch mounted on the top of the brake drum 97 and comprising three pivoted arcuate weights having friction linings on their outer faces, expands and engages the flanged inner surface 99 of the pulley 94 whereby the receptacle rotates at the same speed as the pulley 94 for a spin-drying operation and its gyrating motion ceases. The contractible brake 98 is operated electrically by the arrangement shown in the upper part of Fig. 11, wherein 108 is a cranked lever connected to the free end of the brake band 98, the brake being normally held on by spring 13 connected to the operating lever 108 by a stirrup 115. Also attached to the stirrup at 118 is a plunger 117 actuated by solenoid 116, so that upon energization of the solenoid the brake is released. The clothes receptacle comprises inclined L-shaped deflectors 42 of triangular cross-section and preferably having rounded grooves adjacent the edge of the long leg. Anti-vibration arrangements.-In the event of excessive vibration, a vibration-responsive switch completes a circuit to apply a brake temporarily to the brake drum 97 to slow down the clothes container ; in a modification, excessive vibration causes the brake drum to come into contact with a stationary cylindrical brake shoe. Fig. 10 shows a pendular vibration switch, which may be attached to the interior of the washer casing in one corner thereof. A frusto-conical weight 156, electrically conducting, is suspended freely in a ring-shaped member 153 so that undue vibration causes the weight to swing and complete a circuit through a brake-actuating solenoid 127. The device preferably operates at low voltage a step-down transformer 157 being connected to the mains. By vertical adjustment of the weight 156 on its supporting wire the sensitivity of the switch is varied. Fig. 11 shows the solenoid 127 which on energization retracts the plunger 128 to move the pawl 126 against spring 131 to engage ratchet teeth 125 and slightly rotate the plate 124. Rotatably mounted above plate 124 is a second plate 122 which is connected to the first by spring 123 and which carries a brake shoe 121 for contacting the inside face of the brake drum 98. Thus, each electrical impulse received from the vibration switch rotates the plate 124 by one tooth and applies the brake. The brake is released slowly and the plate 124 returned to its original position by a dashpot arrangement 142, see also Fig. 13. This comprises a cylindrical container 138 having ratchet teeth 145 and containing a viscous fluid; within the container and close to its outer wall is a stationary depending annular member 141 so that rotation of the outer cylinder is impeded. The lower plate 124 has pivoted thereto a pawl 146 which engages the teeth 145 of the cylindrical container and which is connected bv a spring 148 to the base-plate. Thus when the pawl 126 moves the plate 124 one tooth and applies the brake, pawl 146 slips over a tooth 145 and spring 148 then tends to pull off the brake, such motion being delayed by the drag between the cylindrical container 138 and the stationary inner member 141. An alternative anti-vibration arrangement is shown in Fig. 16, in which the whole mechanism is secured to a plate 303 having four legs 322 resting in cups 239 so as to permit of some vibration. The cups 239 are carried by a boxsection frame 323 to which are secured the outer casing 301 and web member 326, which carries a cylindrical member 325 having a friction material 316 secured to its top outer edge. The friction material is surrounded, with small clearance, by the brake drum 319 which rotates during the spin drying operation. Thus excessive vibration of the mechanism during spin drying causes the brake drum to contact the stationary friction material 316 to reduce the speed of rotation until the vibration is reduced to permissible limits. The box-section frame 323 is supported on the ground by four adjustable feet 283, one of which may be the spring-loaded hydraulically damped foot 41. Water circulation.-Water at about 150‹ F. for washing is supplied by means of a known thermostatically-controlled mixing valve to the inlet 213, Fig. 7, and at about 100‹ F. for rinsing to the inlet 214. Electrically-controlled valves 215 or 216 admit the hot or warm water to the hose 209 which discharges the water into the top of the clothes receptacle by nozzle 35, Fig. 1. In the bottom of the tub 30 is a floatcontrolled switch (not shown) which causes the valve 215 or 216 to close when the water reaches a certain level; or to re-open if necessary to maintain such level. The water from tub 30 drains down into the continuously-running centrifugal pump 158, Figs. 7 and 9, from which it passes either into pipes 174, 175 for discharge into the clothes receptacle through nozzles 36, or into the drain outlet 165, according to the position of the electrically-actuated double valve 167, 168. Fig. 7 shows a solenoid 177 for operating this valve. Operation.-The control knob 27, Fig. 1, is turned slightly to rotate the cams 225, one of which switches on the small motor which thereafter rotates the cams, although they may be advanced by the control knob at any stage if desired. The different cams then actuate switches to close the drain and open the hot water valve and after a short interval the main motor is switched on for washing. At the end of the washing period the drain is opened and the brake released to spin-dry.