Patent GB-1051537-A (GB)
IPC: H01H43/12
Abstract: 1,051,537. Timed control of electric circuits. CONTROLS COMPANY OF AMERICA. May 15, 1964, No.22193/63. Heading G3T. [Also in Division D1A] A washing machine timer comprises master and slave switch controllers having cam banks 15 and 13 driven by motors 21 and 16. In the master bank, one cam 15a operates an inversing switch IS for reversing the wash motor 31. The remaining three cams 15b, 15c, 15d determine the time base. Cam 15b has a single cam projection and rotates one revolution per minute, to close a switch SS, in the circuit of the slave motor 16. Cams 15c and 15d have two and four cam projections respectively and act on switches SS 2 , SS 3  paralleled with the switch S, to vary the time base in cooperation with a time base selection cam 131 of the slave bank. In T is bank, one cam 13a operates a holding switch HS which opens to stop the slave motor. This cam may have sixty cam projections corresponding to a possible maximum of sixty operations in a complete programme. The next five cams b to # are programme-selection cams whereby the intervals in which it is desired to effect an operation can be selected and the remaining intervals skipped. Each programme-selection cam acts on a doublethrow switch, two of which are shown at P 1 S 1 - P 1 S 2  and P 2 S 1  - P 2 S 2 . A programme is selected by press-buttons PBS 1  - PBS 2 . At each step of the slave bank, the operative selection cam closes one pair of contacts (P 1 S 2  or P?S 2 ) if an operation is to be performed in the interval, but closes the other pair (P 1 S 1  or P 2 S 1 ) if the interval is to be skipped. The length of each interval is determined by the effective one of the time base cams 15b, c, or d. The remaining slave cams g.to k actuate switches controlling functions of the machine. In circuit with P 1 S 2  and P 2 S 2  are the wash motor 31 with switch FS 2 , a switch WS responsive to water level in the tub and an associated by-pass switch BWS. This prevents energization of the wash motor until either WS is closed on its "Full" contact F or BWS is closed. There is a spin motor 33 with switch FS 3 , and a solenoid-operated water valve 34 with switch FS 4 ; these cannot be energized until BWS is on "Empty" contact E. Switches P 1 S 1  and P 2 S 1 , are connected through one of the starting switches SS 1 , SS 2 , SS 3  and thermostat TS with by-pass switch BTS to contact F. The starting switches are controlled respectively by time base selection switches TS 1 , TS 2 , TS 3  which are selected by slave cam 13l. A pump 36 and switch FS 6  are provided. Switches F 1 S 2  and P 2 S 2  prevent energizing parts of the machine when skipping intervals, whilst P 1 S 1  and P 1  S 2  energize the slave motor. A third press-button PBS 3  serves to start or effect continued rapid advance. The line voltage is disconnected at the end of a main wash cycle by switches LS 1  - LS 2 . In a typical programme, assuming PBS 2  selected and PBS 3  closed, slave cam 13a closes holding switch HS and is rotated one step, whereupon HS opens to stop the slave and the timer is in its first interval. If P 2 S 2  and FS 4  are closed (WS being on "Empty"), water valve 34 opens to fill the tub. FS 3  is held open to stop the spin motor 33. If BWS is closed, the clothes can be given a cold pre-wash if FS 1  is closed or a warm one if FS 1  and FS 2  are both closed. Master motor 21 will close SS 1  once in each cam revolution. Assuming BTS . open, the thermostat TS being open will prevent energization of the slave motor and the timer will remain in this interval. When WS has moved to "Full", the wash motor and heater 32 will be energized if FS 1  and FS 2  are closed, and later TS will close. Upon the ensuing closure of SS 1 , the slave cams will step on and place the timer in the next interval. Normally at this point P 2 S 2  will be closed for several intervals to complete the wash, whereupon FS 6  will operate drain pump 36. Closure of FS 4  will open valve 34 to introduce rinse water while wash motor 31 still operates. After successive rinses and a final drain, spin motor 33 operates to complete the programme.