Patent GB-521771-A (GB)
Title: Improvements in or relating to dishwashing machines primarily for household use
IPC: A47L15/16
Filed: 1938-11-25
Abstract: 521,771. Dish-washing machines; valves. HERTZ, J. Nov. 25, 1938, Nos. 34421 and 34422. 'Convention dates, Nov. 26, 1937 and July 27, 1938. [Class 138 (i)] [Also in Group XXIX] In a dish-washing machine having several spraying nozzles or groups of nozzles supplied with liquid by a domestic water main, valve means comprising a relatively movable piston and cylinder are provided for connecting the nozzles or groups separately and in sequence to the main. Nozzles for rinsing water and cleansing solution may be so controlled, or the nozzles for cleansing solution may operate simultaneously for a predetermined period. As shown, a container 1, Fig. 1, is fitted with a rotary rack 4, a drain 3, and groups of nozzles 18, each group being connected to a separate supply pipe 17. Within the container is a cylinder 7 in which is slidable a piston 8 connected by links 21, 22 to a weighted, toothed, sector 24. The piston has a longitudinal bore 11 connected to the water main 12 and to a cross bore 13 extending to the surface of the piston. The cylinder is provided along its length with outlets 16, 19 connected to the nozzle pipes 17. The lower end of the cylinder is connected by a suction pipe 14 to a small liquid reservoir 50, and is fitted with a restricted vent 15. In use, the piston is raised to its highest point, drawing in liquid at 14, and the water is turned on at the main 12. When the piston is released, it descends under the influence of the weight 27, at a speed determined by the vent 15, and thus connects each pipe 17 in turn to the main 12. At the same time, the sector 24 rotates the rack 4 through gearing 28, 29. The main 12 may have a controllable connection to a supply of cleansing material, so that a first descent of the piston may produce a detergent spray, and a second descent a rinsing spray. As shown, however, the piston 8 is rotatable by means of a handle 30, so that the bore 13 can register with pipes 32, leading to separate detergent nozzles. The various pipes 32 would be fitted with cartridges of different cleansing material adapted to be dissoved by the water. The piston makes its first descent with the bore 13 registering with the pipes 32, and its second with the bore registering with the pipes 17. The bore 13 may be enlarged or duplicated, so that two or more pipes 17 may be connected simultaneously to the main 12. The fluid control means may be operated electrically or hydraulically, and the racks 4 may be driven by a water motor. Various arrangements of the rinsing and detergent nozzles may be adopted. In a modification, the water main is connected through a three-way cock to the bore 11, to separate detergent nozzles,' and to the lower end of the cylinder. It is first connected to the lower end of the cylinder, so as to raise the piston against the action of a spring. It is then connected to the detergent nozzles, which operate during the period that the spring is driving the piston to its lowest point. The piston is again raised, and the cock connected to the bore 11, so that the rinsing nozzles operate in sequence.