Vapor compression refrigerating cycle, control method thereof, and refrigerating apparatus to which the cycle and the control method are applied

A vapor compression refrigerating cycle comprising a compressor, a condenser, a regeneration heat exchanger, an expansion means, and an evaporator connected in series,

• wherein said cycle is based on a cycle corresponding to a reversed Ericsson cycle in which isothermal heat dissipation process and isothermal heat absorption process occur overstriding a saturated vapor line and saturated liquid line respectively and heat exchange is carried out between isobaric heat dissipation process in a liquid zone and isobaric heat absorption process in a superheated vapor zone,
• wherein a process part occurring in a superheated vapor zone of said isothermal heat dissipation process in said reversed Ericsson cycle is substituted by adiabatic compression process and isobaric heat dissipation process, said adiabatic compression being carried out by said compressor and said isobaric heat dissipation being carried out in said condenser together with remaining process part occurring in said superheated vapor zone of said isothermal heat dissipation process under isothermal and isobaric condition, a part of said isobaric heat dissipation process in the liquid zone is carried out in said regeneration heat exchanger by releasing heat from refrigerant liquid in the liquid zone to refrigerant vapor entering said compressor, remaining process part of said isobaric heat dissipation process in the liquid zone is substituted by isenthalpic or isentropic expansion, the expansion being carried out by said expansion means, and expanded refrigerant is introduced to said evaporator to carry out isothermal and isobaric heat absorption and then to be sucked into said compressor, and
• wherein said regeneration heat exchanger is located so that its vapor side is between said evaporator and compressor and its liquid side is between said condenser and expansion means, and a control means is provided for controlling refrigerating capacity by controlling dryness of refrigerant vapor entering the vapor side of said regeneration heat exchanger.