Patent GB-725913-A (GB)
Title: Improvements in and relating to dishwashing apparatus
IPC: A47L15/44
Filed: 1953-09-15
Abstract: 725,913. Dishwashing machines. GENERAL ELECTRIC CO. Sept. 15, 1953 [Sept. 15, 1952], No. 25521/53. Class 138 (1). A dishwashing apparatus has a detergent dispenser comprising a plurality of cups to receive individual charges of detergent, means responsive only to enforced water circulation in the machine to remove detergent from one or more cups, guard means for covering the remaining cups, means for maintaining the guard means in covering position during the said enforced water circulation period to prevent water entering said remaining cups, and means to operate the guard means and expose said remaining cups during a succeeding enforced water circulation period during which detergent is removed from those cups. The invention may be applied to a manually controlled dishwasher or to an automatic timed cycle type dishwasher e.g. as described in Specification 688,939. The detergent dispenser may be fitted in a side wall of the tub of the machine but as shown in Figs. 2 and 4 it is mounted in a recess 51 of the interior panel 50 of a door for the front opening of the tub similar to that described in Specification 688,939. As shown the detergent dispenser comprises a container 20 provided with two cups 21, 22 of which 21 is the larger, and a gate 30, constituting the guard means, which is pivoted on a spindle 26 to the container 20. Two cups 32, 33 are formed in the gate 30, the. larger cup 32 being provided with an outlet hole 41 covered by a removable filter screen 42. The centre of gravity of the gate is so arranged that when its cups are empty it will remain in the position shown in Fig. 4, after having been so placed, and the right hand portion of the gate masks the cup 22. Between the flanges 27, 28 of the container 20 and the wall of the recess 51 are formed drainage channels 27.1 and 28.1. When the gate is in the position shown in Fig. 2, portions 37, 38, 39, of the gate overhang the flange 28. A strip 29.1 is fitted across the two cups 21, 22 Fig. 4 in order to retain charges of dry detergent therein. These charges are placed in the cups when the door is open and in a substantially horizontal position and thereafter the gate is positioned to cover the cup 22 and the door is closed. When the automatically timed cycle of operations of the dishwasher is commenced water will be sprayed from the centre of the top of the tub e.g. as described in Specification 688,939. This water will not contact the detergent in the cups and any that flows down the interior wall of the door will be diverted from the cups by the channels 27.1, 28.1 and the portions 37, 38. The small amounts entering the cups 32, 33 will be insufficient to effect the balance of the gate 30. When the first washing operation is effected the water in the sump of the tub will be thrown-up by an impeller (not shown) and this water will remove the detergent from the open cup 21. At the same time both cups 32, 33 of the gate will be filled with water and the balance will still be preserved since the water entering 32 exceeds the outflow from the hole 41. When this washing operation is completed the tub is drained and during an inoperative period of the cycle the cup 32 drains (in 10 secs.). The water remaining in the cup 33 then causes the gate to pivot to the position shown in Fig. 5 in which position it will remain since the centre of gravity will then be to the left of the pivot 26, and the cup 33 will drain. During a second washing cycle the detergent in the now exposed cup 22 will be removed. The container 20 may be formed with four cups, two of which may be coverable by the gate so that e.g. soap powder and a water softener may be dispensed simultaneously during the first wash period and a detergent and wetting agent dispensed simultaneously during the second wash period. In another embodiment described with reference to Figs. 7 to 10 (not shown) the bottom portions of the cups 21, 22 as viewed in the closed position of the door, are arranged so as to contain liquid detergent, and siphons are placed in each cup. The bends of the siphons are normally above the liquid levels in the cups but when water is introduced thereinto by the impeller action, the levels rise above the bends to start the siphoning actions to evacuate the cups.