GB1004000A - Refrigeration apparatus - Google Patents

Abstract

1,004,000. Ice-making. WHIRLPOOL CORPORATION. Nov. 11, 1963 [Nov. 13, 1962], No. 44496/63. Heading F4H. An ice-making device is disposed in a refrigerated chamber and includes a thermostat which controls both means for initiating ejection of the ice from the device and the refrigerating means for the chamber. As shown in Fig. 4 the ice-making device comprises a mould 20 having compartments 28, an ejector-blade 29 mounted on a shaft 30 being arranged above the mould. Operation of the ice-making device is controlled by an assembly 25 including a thermostat 33 and a cam 37 arranged to cooperate with a pivoted plate 40, a cam 38 arranged to actuate a switch 42 and a cam 39 arranged to actuate a switch 43. Plate 40 is arranged to operate a switch 41 and to rotate a spring-biased arm 26 into and out of a collecting bin to sense the level of ice therein. When, initially, water is in the mould the control means are in the states shown in Figs. 2 and 3 and their subsequent operation is as follows. When the water has completely frozen a moving contact 61 of thermostat 33 moves from a contact 63 to a contact 62 to deenergize the compressor 16 of the refrigerating system of the chamber (Fig. 1, not shown) in which the ice-maker is disposed, and to energize, via switch 41, a motor 36 driving shaft 30 and heaters 31 and 35. The former heater is disposed adjacent the walls of mould 20 and the latter adjacent thermostat 33. After a small amount of rotation of cam 38 switch 42 is closed to maintain motor 36 energized independently of thermostat 33. On further rotation cam 37 causes plate 40 to rotate arm 26 upwardly and to open switch 41. Ejector blade then engages the ice-bodies I, motor 36 stalling until heater 31 has freed the ice, to remove them from the mould. Continuing rotation of cam 37 permits plate 40 to return to the position of Fig. 3 thus lowering arm 26 and closing switch 41. During this time heater 35 has caused thermostat 33 to re-energize compressor 16 and further rotation of cam 39 closes switch 43 to energize a water valve solenoid 24 to deliver water to the mould. After a preselected time switch 43 is opened and finally cam 38 reopens switch 42 to deenergize heaters 31 and 35 and motor 36. The above cycle is repeated until such time as the collecting bin is full and arm 26 is prevented from returning to its lowermost position so that switch 41 remains open and a new cycle cannot be initiated by thermostat 33 until the bin is emptied. Under these conditions thermostat 33 is responsive to the temperature of the refrigerated chamber and serves only to cycle the compressor 16 to maintain said temperature within a predetermined range, it being necessary however to adjust the cut-in temperature setting of the thermostat to compensate for the fact that the temperature sensed by the thermostat is lower than that prevailing in the chamber due to the presence of ice in the mould. This disadvantage is obviated in the embodiment of Figs. 5 and 6 (not shown), in which the switch 41 is connected in series with switch 42 and is mounted on plate 40. The latter is spring- biased towards cam 37 so that switch 41 is closed thereby except when arm 26 is interrupted in its downward movement and plate 40 is held while cam 37 moves away therefrom. On such opening of switch 41 motor 36 is deenergized before switch 43 is closed to supply water to the mould and heaters 31 and 35 are also de-energized so that thermostat 33 is responsive directly to the temperature of the refrigerated chamber. Specification 879,634 is referred to.