Vapor compression type refrigerating system

A refrigerating system comprising:

• a compressor for compressing the refrigerant;
• a heat emitter for cooling the refrigerant compressed at the compressor, the pressure in the heat emitter being higher than a critical pressure of the refrigerant;
• a first pressure reducer for reducing the pressure of the refrigerant from the heat emitter, the first pressure reducer being for controlling the pressure at the outlet of the heat emitter in accordance with the temperature of the refrigerant at the outlet of the heat emitter;
• a separating means for separating the refrigerant issued from the first pressure reducer between a gaseous phase and a liquid phase;
• a second pressure reducer for reducing the pressure from the separating means, the second pressure reducer being for controlling the flow amount of the refrigerant in such a manner that a degree of a super heat at the inlet of the compressor is controlled to a predetermined value, and;
• an evaporator for evaporating the refrigerant from the second pressure reducer.

A refrigerating system comprising:

• a compressor for compressing the refrigerant;
• a heat emitter for cooling the refrigerant compressed at the compressor, the pressure in the heat emitter being higher than a critical pressure of the refrigerant;
• an adjustable pressure reduction valve for reducing the pressure of the refrigerant from the heat emitter;
• an evaporator for evaporating the refrigerant from the pressure reduction valve;
• a microprocessor for operating said pressure reduction valve such that the temperature and the pressure of the refrigerant at an outlet of the heat emitter are controlled along the optimum control line to maximize a coefficient of performance COP=.sub..DELTA. i/.sub..DELTA. L of the refrigerating cycle, and;
• an additional refrigerant control system for additionally controlling a condition of the refrigerant, thereby obtaining a desired operation of the refrigerating system, comprising:
• an additional adjustable pressure reduction valve arranged downstream from said pressure reduction valve, and;
• a microprocessor for controlling the additional pressure reduction valve for controlling a degree of a super heat at the inlet of the compressor.

A refrigerating system comprising:

• a compressor for compressing the refrigerant;
• a heat emitter for cooling the refrigerant compressed at the compressor, the pressure in the heat emitter being higher than a critical pressure of the refrigerant;
• a first pressure reducer for reducing the pressure of the refrigerant from the heat emitter, the first pressure reducer being for controlling the pressure at the outlet of the heat emitter in accordance with the temperature of the refrigerant at the outlet of the heat emitter;
• a refrigerant gas/liquid separator for separating the refrigerant issued from the first pressure reducer between a gaseous phase and a liquid phase;
• a second pressure reducer for reducing the pressure from the separator, the second pressure reducer being for controlling the flow amount of the refrigerant in such a manner that a degree of a super heat at the inlet of the compressor is controlled to a predetermined value, and;
• an evaporator for evaporating the refrigerant from the second pressure reducer.