Patent GB-663586-A (GB)
Title: Improvements in and relating to dish-washing apparatus
IPC: A47L15/50
Filed: 1949-05-12
Abstract: 663,586. Dish washing machines. BRITISH THOMSON-HOUSTON CO., Ltd. May 12, 1949 [May 14, 1948], No. 12706/49. Class 138 (i) In a dish-washing machine, a charge of detergent is added to the liquid automatically when a pre-determined quantity of washing liquid has accumulated in the vat. Means are preferably provided for cutting off the supply of washing liquid when a larger pre-determined quantity thereof has accumulated. The machine described is of the type in which a cycle of operations are automatically performed, including rinsing stages, washing stages, further rinsing and heat for drying. When sufficient washing liquid has been introduced, the extra load on the impeller may be arranged to shut off the water supply in known manner. During the rinsing and washing stages, and the first part of the heating stage, an impeller in the bottom of the vat runs continuously for throwing water upwardly. A charge of detergent is placed in a pocket in the door of the machine, and the detergent is washed out of the pocket during the first washing stage when the liquid level reaches the pocket. Fig. 1 show the general arrangement in which an impeller 18 is mounted on the shaft of an electric motor 22. Upon actuation of the push button start switch 45 the motor 22 is started and timing mechanism behind the panel 44 actuates in the desired sequence the normally closed inlet valve 27 which admits water to the spray head 25, and the solenoidactuated normally closed drain valve 31. A heating element 42 is switched on after the washing is completed, the agitator 18 then distributing the hot air; the motor 22 is then switched off and later the heat is switched off to complete the cycle; the washing chamber is vented to atmosphere by a louvred panel 17 to facilitate drying. The handle 16 of the front door is arranged so that the circuit is completed only when the handle is locked. Fig. 2 shows the door open and the dish-carrying racks removed. The door has two communicating pockets 83, 84 near its lower edge; a charge of detergent is placed in pocket 83, and is washed out of pocket 84 when the water level has risen sufficiently, since the impeller 18 rotates anti-clockwise. During the preliminary rinsing stages when water is sprayed in with the drain valve open, a certain amount of water is flung up and runs down the door; deflectors 85, 86 are provided on the door to guide such water to chutes 87, 88 whereby the water is returned to the vat without displacing any of the detergent from pocket 83. As shown in Fig. 6, the dish-carrying racks comprise a bottom rack 102 depending from a frame 101, and a separate upper rack which rests on the frame. Frame 101 rests on a pair of runners fixed to the inside of the washing chamber, movement of the frame and dishes in and out being facilitated by providing a roller 120 on each side of the frame at the back and a roller 119 on each runner at the front. The runners slope back slightly to bias the frame towards its working position. The bottom of the wire basket 102 carries a roller 121 which engages a runway 82 on the door, the runway sloping down away from the washing chamber so as to bias the frame towards its outermost position when once it is pulled partly out.