Patent GB-773080-A (GB)
Title: Improved dish washer machine
Inventor: ABRESCH CAREL F
IPC: A47L15/23
Filed: 1955-04-07
Abstract: 773,080. Filters. GENERAL MOTORS CORPORATION. April 7, 1955, No. 10181/55. Class 46. [Also in Group XXIII] Relates to filtering means for washing liquid in a dishwashing machine (see Group XXIII). A central opening 59, Fig. 2, in the sump 56 of a dishwashing chamber 28 is connected through the agency of a rubber sealing ring 63, Fig. 10, to the inlet flange 58 of a pump 60 having an impeller 62 rotatable by a motor 66. Mounted on the edge of the ring 63 within the opening 59, is an annular support 187 carrying an X-shaped vertical guide 195. Slidable on the guide 195 is the annular base 191 of a perforated strainer 189 the top wall 197, Fig. 2, of which is slidable on a rod 194 carried by the guide. The strainer is normally urged upwardly by a light spring 193 disposed on the rod 194 between the guide 195 and wall 197, upward movement being limited by a cap nut 199 on the rod. The pump outlet is connected by a two-way valve 70, to a tube 94, which is connected to the spray tube inlet fitting 96, and to a drain tube 92, the valve 70 being operable by a solenoid 72. When the solenoid is operated,-the pump outlet is connected to the tube 94 and when de-energized the pump outlet is connected to the drain tube 92. A pressureresponsive switch 89 is provided in the bottom wall of the sump and arranged to open when the level of water reaches the position indicated in Fig. 2, this switch being arranged in series with the solenoid for a water inlet valve 40, Fig. 8. At the commencement of the cycle of dishwashing operations the sump is empty and the strainer 189 is raised to the position shown in Fig. 10 by means of the spring 193. After a switch 241, Fig. 8, is operated, the inlet valve 40 is opened, and a timer motor, motor 66, together with a heater and a pilot light 234 are energized. For a short period hot water enters the chamber through a nozzle 44 to issue over the dishes, large loose particles thereon being carried away, under the strainer and through the pump to drain. Thereafter the timer motor, heater and pilot light are energized for continuous operation, the motor 66 de-energized and the solenoid 72 energized so that the sump commences to fill with water. The pressure switch 89 is then operated to close the inlet valve but in any case the timer, shortly afterwards, positively renders the inlet valve circuit inoperative. The motor 66 is then re-energized and water is pumped to a spray tube 98 and, due to the tangential inlet of a fitting 96 (described with reference to Figs. 4 and 5 (not shown)) and the jet apertures 147, 149 and 151, the spray tube rotates. The pump sets up a pressure differential on the strainer 189 whereby the latter is drawn downwardly against the action of the spring 193 to the position shown in Fig. 1 or Fig. 2, and loose particles washed from the dishes are prevented from entering the drain opening 59. After a period of washing the solenoid 72 and motor 66 are deenergized for a short period. This allows the strainer to rise and for water and particles to pass through the pump to drain. The motor 66 and solenoid of the valve 40 are then reenergized whereafter a flush-rinse is effected, the water being pumped to drain. Specification 773,081 is referred to.