Ranco Inc.

Ranco Inc. of Delaware

Mario Gemma

Guglielmo Rossi

Hans Bosing

Burghard Baehr

A pressostat comprises an operating pressure chamber (4) which is limited by its housing (1) and by an operating membrane (5) or the like including a pressure surface for an output adjustment member (3), at least one spring counteracting the pressure (P) in the operating pressure chamber (4), a switch member (2) which responds when a limit pressure value is exceeded in said working pressure chamber (4), and an enclosed protective chamber (6) arranged concentrically to the working pressure chamber (4) limited by the housing (1), the operating membrane (5) and a protective membrane (7) or the like including pressure surface for the output adjustment member (3). In order, if a fracture of the operating membrane takes place, to ensure switch-off at a substantially lower limit pressure value, there is a first spring (10) counteracting the pressure (P) in the operating pressure chamber (4) arranged outside the operating pressure chamber (4) and the protective chamber (6), and a second spring (9) counteracting the pressure (P) in the operating pressure chamber (4) is arranged within the operating pressure chamber (4), and the pressure surfaces of the two membranes (5, 7) are detachably interconnected via an intermediate member (8) which is firmly connected with one of said pressure surfaces.

Pressostat for pressure sensitive activation

Thermostat with temperature pull-down facility

The accumulation of ice on a surface such as an evaporator fin in a refrigerator unit is detected by a mechanical probe which is moved by a bimetal bender element upon periodic timer-controlled energization of a bimetal heater so as to pass over the surfaces of an evaporator fin. If the movement of the probe is obstructed by ice on the evaporator fin surfaces a switch is operated by a bistable mechanism, causing energization of a defrosting heater and switching off the refrigerator compressor motor. If no ice is detected the probe returns to its original reset position without operating the defrost control switch.

Growing community of inventors

Linkenheim-Hochstetten, Germany

Mario Gemma