Patent GB-455438-A (GB)
Title: Improvements in and relating to dishwashing machines
IPC: A47L15/42
Filed: 1935-04-24
Abstract: 455,438. Dish-washing machines. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London. April 24, 1935, No. 12365. Convention date, April 24, 1934. [Class 138 (i)] A dish-washing machine comprising spray or impeller devices has fluid supply and draining valves operated by cams in a predetermined cycle. A manually operated device controls the electrical operation of the cams on a shaft which in turn controls electrical means to set the apparatus for different operations such as rinsing, filling, washing, draining, &c. Dishes &c. are placed in supporting trays within a vat 14, Fig. 2, and a cover 15 is closed. An indicating dial 114, Figs. 1, 7, should then be in its " off " position. An inlet valve 52, Fig. 1, is closed and a detergent valve 68 connected to a soap supply 63 also closed, a drain valve 38 will be open, an impeller motor 23 will be de-energized and so will a lamp 128. To start the apparatus a push-button 88 will be depressed. This will close a switch 86, Fig. 3, which becomes locked by a detent 91 engaging a member 96. A circuit is made from mains 74, 75, Fig. 1, to an electromagnetic device 78 through conductors 135, 136. The device 78 then turns a cam-shaft 72 to the " rinse " position in which a cam 61 opens an inlet valve 52 to allow liquid from conduit 48 to flow through a reaction spray device 47a, Fig. 2. A cam 77, Fig. 1, closes a switch 76 so as to energize the motor 23 through conductors 136a, b, 136 and a cam 132 operates a switch 131 to light a lamp 128. This circuit is completed by the cam 132 until the controlling apparatus is returned to its " off position. At the end of the rotation of the shaft 72 by the electromagnet 78 a cam 103 momentarily closes a switch 102 to energize an electromagnetic device 97. This releases the latch 91 to open the switch 86 de-energizing the electromagnet 78 which is returned to zero by a spring 85. The electromagnet at the same time advances the dial 114 to " rinse ". Water then flows into the vat from source 48 through the spray 47a so as to rinse the dishes and will continue until the control is altered. To effect the washing proper the button 88 is again pushed and the electromagnet 78 advances the shaft 72 to "fill." The inlet 52 remains open, the drain valve 38 will be closed and the detergent valve 68 will have been opened by a pin 70 on the cam 61 so that water can flow from the main supply through conduit 65 to the bottom of the detergent chamber 63. This causes the upper portion in the chamber to flow into the vat through the conduit 64. The switch 102 will have been closed to cause the electromagnet 97 to release the switch 86 and advance the dial 114 to " fill." The motor 23 instead of being energized through the switch 76 will be energized through the coil of the magnet device 105 by the switch 107 through a conductor 136b and 136. Water then flows into the vat from the source 48 through the spray device, but instead of flowing directly to the drain will accumulate above the closed valve 38. As the water deepens the load on the impeller and motor increases and the armature current will cause the magnet 105 to attract a latch 111 and release a switch 106 which completes a circuit to the magnet 78. The cam - shaft then advances to the " wash " position. The cams will close the valve 52 and the detergent valve 68 and the drain 38. The cam 77 will have closed the switch 76 so as to connect the motor 23 to the supply 74, 75 and the cam 108 will have allowed its switch 107 to open, cutting the magnet 105 out of the motor circuit. The cam 110 will have operated the switch 106 to its open position where it will be latched by the member 111. The switch 102 will have been temporarily closed to advance the dial to " wash." No more water will flow into the vat and the motor will continue the wash. To discontinue the wash the button 88 is again depressed to cause the magnet to advance the shaft 72 to the " drain " position and the switch 102 to advance the dial similarly. During this operation, the inlet and detergent valves will be closed and the motor circuit will still be completed through the switch 76, but the drain valve 38 will be opened by the cam 73. The apparatus is now ready for the second washing operation. The button 88 is again depressed and the cam-shaft advanced to the second " fill " position and also the dial. The operation is similar to the first except that the detergent valve is closed. Washing will continue till a second draining brought about by depression of the button. The apparatus is now ready for the final rinse and so to the " off " position. It is not necessary to go completely through the cycle as the attendant can depress the button successively till the control desired is attained.