GB832756A - Dish washing machines - Google Patents

Abstract

832,756. Dish washing machines. COLSTON Ltd., C. Nov. 22, 1956 [Dec. 23, 1955], No. 36982/55. Class 138(1). A dish washing machine comprises a powerdriven rotary tubular impeller with orifices to discharge jets of liquid in the direction of rotation and at an angle other than radial, and with an interior surface so arranged that washing liquid continuously supplied thereto is constrained to revolve with it whereby the total velocity of the jets is that due to the impressed centrigugal head of liquid within the impeller plus the peripheral velocity of the impeller. The power used to deliver the liquid is low relatively to that used for driving the impeller. In the form shown in Figs. 1 and 2, a horizontal cylindrical plastic impeller 10 is mounted substantially centrally within a cubical washing chamber 4 with a full-width front-opening door 5 hinged at 6. The impeller is rotated about a slotted water-supply tube 12 by means of a spindle 16, a pulley 32 and a driven belt B. The latter also drives the pulley 31A of a pump 30 which draws water through a filter screen 27, past a heater H in a sump 25 and re-circulates it through passage 21 to the tube 12. The impeller 10 is formed with three nozzle heads 35 each having a row of elongated slots 33 providing jet orifices. Fig. 4 shows a pressed-metal impeller formed with nozzles 37 terminating in discharge slots 36. Fig. 7 shows a plain cylindrical impeller 40 with staggered rows of discharge holes 41 adjacent portions 42 producing substantially tangential jets, a rib 43 being arranged behind each row of holes. Alternatively, longitudinally extending orifices may produce sheet-like jets of water. The Provisional Specification also refers to an impeller rotating about a vertical axis, and the use of the pump, after draining of the cabinet, for pumping in drying air from the exterior, a heater being disposed between the pump and the impeller.