ES351381A1 - Dishwashing Machines - Google Patents

Abstract

A constructional unit for use in a spray dishwashing machine comprises a water inlet valve 39, a water level control device 49 for closing the valve 39 when a desired level is reached in the machine, a drain pump 15, a spray pump 12 for delivering water to the dishwashing sprays, timing mechanism for controlling the opening of the valve 39 and the operation of the pumps 12, 15, and a single motor 10 for driving the pumps and timing mechanism. The timing mechanism comprises a main cam 34 driven via pinions 17, 22, worm 23, wormwheel 24, worm 25, wormwheel 26, and a clutch 27. The shaft carrying the cam 34 also carries a pinion 34A which drives via a pinion 34B, a shaft 32 carrying cams controlling a rinse aid injector 71, the motor 10, and a heater (not shown). When required the shaft 32 is driven at a higher speed by engagment of a clutch 33 driving bevel gears 28, 29. The main cam 34 actuates the valve 39 via a cam follower 48 and a push rod 46, and also controls, via a cam following surface 57 on a bell crank lever 56 and linkage 84, 58, a clutch 14 in the drive between the motor 10 and the drain pump 15. The water level control device 49 comprises a diaphragm 53 responsive to the pressure in a chamber 50, connected by a pipe 51 to the sump of the dishwashing machine, to actuate via a push rod 54 an overcentre linkage 62, 63 to permit springs 47, 61 to displace the cam follower 48 laterally so that the valve 39 closes. The bellows 71 for injecting a rinsing aid into the dishwashing machine is actuated when a cam 35 on the shaft 32 disengages from a cam follower 68 carried by a pivoted arm 66 so that a tension spring 67 operates a rod 69, to compress the bellows 71. A washing, rinsing, and drying programme is described with reference to an electrical control circuit (Fig. 6, not shown).