| 摘要 |
An electronic delay circuit is described, for refrigerator apparatus which has at least two cooling compartments at different temperatures, each of which is cooled by an evaporator traversed by the refrigerant fluid (one for fresh foods and one for frozen foods), a single compressor, a single condensor and a system of capillary tubes. The said electronic control circuit serves to inhibit attempts to restart the compressor, after it has stopped (for whatever reason) whilst the conditions remain non optimal. More particularly, it avoids attempts to restart the compressor whilst the pressures of the refrigerant fluid in the delivery and induction ducts of the compressor are not in equilibrium and/or if a PTC is used in the starter circuit of the electric motor, with the said PTC still hot. The said electronic control circuit even allows the requirement for a starter capacitor to be eliminated. This delay is obtained by discharging a capacitor (which is charged during the operating time of the compressor) through a resistor: the charged condition of the capacitor after the compressor has stopped in fact prevents the commutation of a threshold voltage comparator circuit which is responsible for enabling a new start up of the motor of the compressor. The values of the said capacitor and of the charging and discharging resistors are chosen in such a way that the voltage across the said capactor has substantially, instant by instant, the same variation as the pressure in the condenser of the refrigerator circuit.
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