Self-advancing programmer and pressure actuated devices control arrangement

Claim 1

A control system for an automatic ice maker of the inflatable bladder type, including pneumatic programmer means including a central hollow body portion containing slide valve means having reading means presenting pressure areas and separate suction areas thereon, said body portion including a reading surface provided with an array of apertures therein and along which said reading means is movable to selectively place said pressure areas and said suction areas in registry with selected ones of said reading surface apertures, a first chamber at one end of said body portion, said first chamber containing a first displaceable member therein biased toward said body portion and separating said first chamber into an outer low pressure side space and an inner high pressure side space in open communication with said pressure areas; a second chamber at the other end of said body portion, said second chamber containing a second displaceable member separating said second chamber into an outer side space adapted to receive water for supplying said ice maker, and an inner side space in open communication with said pressure areas; means connecting at least a portion of said slide valve means To said first displaceable member for movement therewith; pump means connected to said programmer and having a suction side in normal communication with said suction areas and a pressure side in normal communication with said pressure areas; means placing said suction areas in communication with said low pressure side space; one of said reading surface apertures comprising a vent opening for selectively venting either said pressure areas or said suction areas in accordance with the registry of either therewith, and for preventing venting of both when said areas are out of registry; means connecting a second aperture of said reading surface to said ice maker for controlling the inflation and deflation of said bladder in accordance with registry of said second aperture with said pressure and suction areas; a pneumatically operated water supply valve for controlling the supply of water to said second chamber outer side space; means for conducting water from said second chamber to said ice maker; means connecting a third aperture of said reading surface to said water supply valve for controlling the admission of water to said second chamber outer space; said aperture of said reading surface being arrayed, relative to the array of said pressure and said suction areas; to effect inflation and deflation of said bladder through registry of said second aperture with a pressure area and then a suction area, respectively, to subsequently effect opening and then closing of said water supply valve through registry of said third aperture with a suction area and a pressure area, and to pressurize said pressure areas in response to an indication that said outer side water space of said second chamber has received the supply of water, to force said water through said water conducting means to said ice maker; said vent aperture being disposed to selectively vent, and prevent venting, of said pressure areas and said suction areas in accordance with the pressure condition to be applied to said ice maker bladder, and said water supply valve, and said water chamber displaceable member, so that the differential pressure imposed across said first displaceable member is achieved by a pressure condition of the same character as that applied to said ice maker bladder, and to said water supply valve, and to said water chamber displaceable member.