Patent GB-628846-A (GB)
Title: Improvements in clothes washing machines
IPC: D06F34/08
Filed: 1947-02-06
Abstract: 628,846. Washing and drying machines. BENDIX HOME APPLIANCES, Inc. Feb. 6, 1947, No. 3635. Convention date, Feb. 20, 1946. [Class 138 (ii)] In a clothes washing machine, a switch in an electric circuit for controlling admission of liquid to a tub is operated at predetermined intervals in a cycle of operations by an automatic mechanism, a second switch in the circuit being controlled by a water-level mechanism to close at a predetermined lowwater level and open at a given high-water level and being short-circuited for a short time during the cycle so that if the float is held inoperative by suds, water can still flow to clear them away and so allow the cycle to continue. Construction.-A casing contains a horizontal tub 11, Figs. 1 and 2, supported on a base 10 by brackets 12, 13. The back of the tub consists of two conical members 14 placed face to face, the apices providing bearings for a rotatable clothes cylinder 15 which is driven by an electric motor 18 through a gear-box 19, a belt 17 and a pulley 16. The tub is driven at low-speed for washing and at high-speed for drying by the mechanism described in Specification 608,822, [Group XXIV]. The change from one speed to the other is controlled by a solenoid 20. The motor 18 also drives a drain pump 21, the intake of which is connected to a sump 22 of the tub 11 by a solenoidoperated valve 23, the outlet leading to a drain pipe 25. Water supply.-Hot and cold water inlets 26, 27, Figs. 1 and 2, are connected to a thermostatically-controlled mixing valve 28 which is further controlled by two solenoids. One solenoid 29 allows hot water only to flow into the tub through a pipe 31, the other 30 controlling the admission of tepid water. To control the amount of water in the tub a switch 40 operated by a float rod 37 is provided. This switch opens the water solenoid circuits when tripped by the float rod 37 at maximum water level. A manual switch 97a is provided to parallel the two solenoids 28, 29 to give tepid water only. Control system.-A sequence controller, Figs. 1 and 3, consisting of four cam-controlled switches driven by a self-starting synchronousmotor 51 through an escapement 52 is mounted in the top of the cabinet. The escapement advances the cams 5 degrees every 45 seconds. The control circuit is shown in Fig. 3. Cam 61 controls the driving and timing motors 18, 51 ; cam 62, the drain and hot water solenoids 24, 29 ; cam 64, the mixed water and motor speed-changing solenoids 30, 20 ; and cam 63 short circuits the float-switch 40 which is arranged to break the circuits of the solenoids 29, 30, 20 when the water level is at its maximum. A control knob 54 is mounted on the cam-shaft and operation is initiated by manually moving the knob 14¢ degrees to allow cam 61 to complete the driving and timing motor circuits. Operation.-When the machine is manually started by moving the control knob, the sequences shown diagrammatically in Fig. 5 are carried out. The first sequence comprises : (1a) a soaking period in tepid water during which the clothes container 15 is rotated at low speed ; (1b) a draining period during which all water is drained from the tub which continues to rotate at low speed, and (1c) the machine stops and the control knob must be manually advanced to restart it for the second sequence, i.e. for the remainder of the cycle which comprises : (2c) washing at low speed in hot water ; (2b) draining ; (2c) sprayrinsing with tepid water with the drain open (during this operation the water level switch is short-circuited by cam switch 63 so that in the event of the float being held above its minimum level by suds, water can still be sprayed into the tub, thus clearing the suds and enabling the cycle to continue) ; (2d) drying at high speed ; (2e) two cycles of deep rinsing at low speed in tepid water with the drain valve shut, each followed by draining and drying at high speed, the last drying period being prolonged ; finally, (2f ) the machine stops.