| 摘要 |
<p>1,193,911. Refrigerating; defrosting. MATSUSHITA ELECTRONICS CORP. 9 Jan., 1968 [13 Feb., 1967], No. 1230/68. Heading F4H. [Also in Division G3] A refrigerator particularly of a domestic type has at least one main compartment and at least one freezing compartment and at least one common evaporator connected to a compressor. In one phase of operation a compressor motor 45 is controlled by a thermistor 27 in the main compartment and in a selectively alternative freezing phase the motor 45 is controlled by a thermistor 37 in the freezing compartment and the temperature in the main compartment is adjusted by a heater 44 controlled by thermistor 27. A defrosting phase is also incorporated which is terminated by the thermistor 37 switched to provide a different temperature range. In position a, b of a switch G thermistor 27 controls motor 45 through a transistor 28 and relay 31 to regulate the main compartment temperature. Periodically e.g. once per 24 hours a timer motor 50 momentarily closes a switch 49 energizing a winding 47 of a defrosting valve and a relay 51, which is held over contacts B which shunt contacts 49, contacts A energizing motor 45 causing hot gas to be passed through the evaporator. When the temperature rises to a point determined by thermistor 37, a relay 41 is energized opening contacts f, g which disconnects the defrosting valve and relay 51, and closing contacts e, f re-energizing motor 45 until the temperature falls so that relay 41 de energizes. In position a, c, of switch G the motor 45 is controlled by thermistor 37 switched to a lower temperature range through a transistor 48 and relay 41. As the main compartment temperature drops below the operating point of transistor 28, heater 44 is energized through contacts f, g of relay 31 to maintain this temperature. In an alternative arrangement Fig. 3 (not shown), a heater (52) replaces the defrosting valve and motor 45 is not run during the defrosting period.</p> |
