Refrigeration and air-conditioning apparatus, refrigerant leakage detection device, and refrigerant leakage detection method
AssigneeMitsubishi Electric Corporation
InventorsYasutaka Ochiai, Makoto Saito, Fumitake Unezaki
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Abstract
A refrigeration and air-conditioning apparatus rapidly varies the pressure or the temperature inside a liquid reserve container to identify a liquid level position inside the liquid reserve container on the basis of the surface temperature of the liquid reserve container.
Claims22
A refrigeration and air-conditioning apparatus including a refrigerant circuit formed by connecting a compressor, a condenser, an expansion valve, an evaporator, and a liquid reserve container to one another by pipes, the apparatus comprising:
- a temperature sensor that measures a surface temperature of a surface of the liquid reserve container;
- and
- a controller that varies a pressure or a temperature inside the liquid reserve container,
- wherein the controller
- varies the pressure or the temperature inside the liquid reserve container by stopping the compressor, controlling an opening degree of the expansion valve, or closing an opening and closing valve provided at the refrigerant circuit so that a temperature difference between a gas-phase portion inside the liquid reserve container and a liquid-phase portion inside the liquid reserve container occurs, and
- detects a liquid level position inside the liquid reserve container, based on a measured value of the temperature sensor when the temperature difference occurs.
A refrigerant leakage detection device for detecting a liquid level position inside a liquid reserve container provided as one of element devices of a refrigerant circuit to detect refrigerant leakage, the device comprising:
- a temperature sensor that measures a surface temperature of a surface of the liquid reserve container;
- and
- a controller configured to vary a pressure or a temperature inside the liquid reserve container,
- wherein the controller
- varies the pressure or the temperature inside the liquid reserve container by stopping the compressor provided at the refrigerant circuit, controlling an opening degree of an expansion valve provided at the refrigerant circuit, or closing an opening and closing valve provided at the refrigerant circuit so that a temperature difference between a gas-phase portion inside the liquid reserve container and a liquid-phase portion inside the liquid reserve container occurs,
- detects the liquid level position inside the liquid reserve container, based on a measured value of the temperature sensor when the temperature difference occurs, and
- detects refrigerant leakage by comparing, with an initial amount of refrigerant, a sum of an amount of refrigerant reserved in the liquid reserve container which is calculated based on the liquid level position and an amount of refrigerant in the refrigerant circuit other than the refrigerant reserved in the liquid reserve container.
A refrigerant leakage detection method for detecting a liquid level position inside a liquid reserve container provided as one of element devices of a refrigerant circuit, based on a temperature of the liquid reserve container, to detect refrigerant leakage, the method comprising:
- controlling at least one of the compressor and the expansion valve, which are actuators, to vary a pressure or a temperature inside the liquid reserve container;
- detecting the liquid level position inside the liquid reserve container, based on the temperature of the liquid reserve container;
- and
- determining whether a refrigerant leaks from the refrigerant circuit by comparing, with a reference amount of refrigerant, a sum of an amount of refrigerant calculated from the temperature of the liquid reserve container and an amount of refrigerant reserved in the liquid reserve container.
A refrigeration and air-conditioning apparatus comprising:
- a refrigerant circuit formed by connecting a compressor, a condenser, an expansion valve, an evaporator, and a liquid reserve container to one another by pipes;
- a liquid level detection sensor that detects an amount of liquid refrigerant within the liquid reserve container;
- and
- a refrigerant leakage detection device that determines whether there occurred refrigerant leakage from the refrigerant circuit by detecting an amount of liquid refrigerant within the liquid reserve container at a predetermined time after stop of the compressor by the liquid level detection sensor, and comparing a value obtained by the detection with a predetermined reference value.
A refrigerant leakage detection device configured to detect refrigerant leakage from a refrigerant circuit formed by connecting a compressor, a condenser, an expansion valve, an evaporator, and a liquid reserve container to one another by pipes, the refrigerant leakage detection device detecting an amount of liquid refrigerant within the liquid reserve container, and comprising a determining section configured to determine whether there occurred refrigerant leakage from the refrigerant circuit based on an amount of excessive liquid refrigerant at a predetermined time after stop of the compressor.
A method for detecting refrigerant leakage from a refrigerant circuit formed by connecting a compressor, a condenser, an expansion valve, an evaporator, and a liquid reserve container to one another by pipes, the method comprising:
- detecting an amount of liquid refrigerant within the liquid reserve container,
- comparing the amount of excessive liquid refrigerant at a predetermined time after stop of the compressor with a predetermined reference value, and
- determining that there occurred refrigerant leakage from the refrigerant circuit when the excessive amount of liquid refrigerant is smaller than the reference value.
Dependencies are inferred from the claim text.