US 7,607,315 B2 · Pressure control valve and vapor-compression refrigerant cycle system using the same

Abstract

A pressure control valve includes a valve portion disposed in a passage from a refrigerant radiator to a suction port of a refrigerant compressor in a vapor-compression refrigerant cycle system. The valve portion controls a refrigerant pressure at an outlet of the refrigerant radiator in accordance with a refrigerant temperature at the outlet of the refrigerant radiator, and the valve portion has a control pressure characteristic in which a pressure change relative to a temperature is smaller than that of the refrigerant. Furthermore, the valve portion may have a fluid passage through which refrigerant flows even when a valve port of the valve portion is closed by a valve body. Accordingly, when the refrigerant radiator is used for heating a fluid, heating capacity for heating the fluid can be rapidly increased at a heating start time.

Claims19

Dependent claims

A pressure control valve for a vapor-compression refrigerant cycle system that includes a refrigerant radiator in which refrigerant having a pressure higher than a critical pressure, compressed by a refrigerant compressor, flows, the pressure control valve comprising:

a valve portion disposed in a refrigerant passage from the refrigerant radiator to a suction port of the refrigerant compressor, wherein:
the valve portion controls a refrigerant pressure at an outlet of the refrigerant radiator in accordance with a refrigerant temperature at the outlet of the refrigerant radiator;
the valve portion has a control pressure characteristic in which a pressure change relative to a temperature change is smaller than that of the refrigerant;
the refrigerant radiator is configured in the vapor-compression refrigerant cycle system to radiate heat to an object to be heated;
and
the valve portion controls the refrigerant pressure at the outlet of the refrigerant radiator to be higher than a pressure value at which the coefficient of performance of the vapor-compression refrigerant cycle system becomes maximum, when a temperature of the outside air is lower than a predetermined temperature.

3 more elements

A vapor-compression refrigerant cycle system comprising:

a compressor for compressing refrigerant to have a pressure higher than a critical pressure of the refrigerant;
a refrigerant radiator for radiating the refrigerant discharged from the compressor, the refrigerant radiator has therein a refrigerant pressure higher than the critical pressure;
and
a pressure control valve for controlling a refrigerant pressure at an outlet of the refrigerant radiator in accordance with a refrigerant temperature at the outlet of the refrigerant radiator, wherein:
the pressure control valve includes a valve portion that has a control pressure characteristic in which a pressure change relative to a temperature change is smaller than that of the refrigerant;
the refrigerant radiator is configured in the vapor-compression refrigerant cycle system to radiate heat to an object to be heated;
and
the pressure control valve controls the refrigerant pressure at the outlet of the refrigerant radiator to be higher than a pressure value at which the coefficient of performance of the vapor-compression refrigerant cycle system becomes maximum, when a temperature of the outside air is lower than a predetermined temperature.

5 more elements

Dependencies are inferred from the claim text.

Pressure control valve and vapor-compression refrigerant cycle system using the same

Life of this patent

Pressure control valve and vapor-compression refrigerant cycle system using the same

Life of this patent

Abstract

Claims19