Provided is a combination valve unit having an improved structure and capable of performing both a pressure relief function for cooling and a pressure relief function for dehumidification. In addition, disclosed is a vehicle heat pump system capable of improving dehumidification performance by actively controlling the refrigerant flow distribution. The combination valve unit serves as a refrigerant throttling means in a vehicle heat pump system, and forms the inlet for a cooling pressure relief unit for performing indoor cooling and the inlet for a dehumidification pressure relief unit for performing indoor dehumidification, respectively.

A heat pump system includes a first bypass pipe provided with a first bypass valve and connecting a liquid refrigerant pipe and a low-pressure refrigerant pipe, a refrigerant heat exchanger configured to cause a heat-exchange between refrigerant flowing in the liquid refrigerant pipe and refrigerant flowing in first bypass pipe, a second bypass pipe provided with a second bypass valve and connecting the liquid refrigerant pipe and the low-pressure refrigerant pipe, and a controller. The controller is configured to control opening degree of the first bypass valve based on detected superheated temperature of refrigerant flowing in the first bypass pipe, and detected discharge temperature of a compressor and control opening degree of the second bypass valve based on the detected discharge temperature.

An integrated valve includes a connecting member including a first valve element and a second valve element. The first valve element is disposed in a pressure reducing chamber of a body of the integrated valve and forms a pressure reducing valve that reduces the pressure of the refrigerant discharged from a compressor. The second valve element is disposed in an on-off valve chamber of the body and forms an on-off valve for adjusting a flow rate of the refrigerant flowing into an intermediate-pressure port of the compressor. The on-off valve is in a fully opened state when the pressure reducing valve is in a throttling state, the on-off valve is in an opened state when the pressure reducing valve is in an opened state, and the on-off valve is in a closed state when the pressure reducing valve is in a fully opened state.

A refrigeration system includes an evaporator, a condenser, a compressor, a capillary tube, and an expansion device. The compressor is configured to circulate a refrigerant between the evaporator and the condenser. The capillary tube is configured to receive the refrigerant from the condenser. The expansion device is configured to receive the refrigerant from the capillary tube and provide the refrigerant to the evaporator. The expansion device is adjustable to control a flow of the refrigerant through the capillary tube.

A test chamber and a method for conditioning air in a temperature-insulated test space of a test chamber, which is sealable against an environment and serves for receiving test material, a temperature ranging from −20° C. to +180° C. being produced within the test space by means of a cooling device of a temperature control device of the test chamber, using a cooling circuit with carbon dioxide (CO.sub.2) as a cooling agent, using a heat exchanger in the test space, using a low-pressure compressor and using a high-pressure compressor downstream of the low-pressure compressor, using a gas cooler, using a storage means for the cooling agent and using an expansion valve, the temperature in the test space being controlled and/or regulated by means of a control device of the test chamber. A gaseous and/or liquid cooling agent is dosed in the storage means by means of a high-pressure valve of the cooling circuit downstream of the gas cooler, the storage means being connected to a medium-pressure side of the cooling circuit upstream of the high-pressure compressor and downstream of the low-pressure compressor via a medium-pressure bypass of the cooling circuit, the gaseous cooling agent being dosed in the medium-pressure side from the storage means by means of a medium-pressure valve when the low-pressure compressor is switched off.

A valve opening circuit mounted on a heat pump device having a valve on a refrigerant circuit includes a DC electric path to which a DC voltage generated from an AC voltage for normal use is applied, a valve drive circuit that opens and closes the valve by using the DC voltage of the DC electric path, a control unit that acquires a control power source voltage based on the DC voltage of the DC electric path and controls the valve drive circuit, and a power feed port connected to the DC electric path and connectable to a DC power source line provided from outside for emergency. The control unit causes the valve drive circuit to open the valve when the AC voltage is lost and the DC voltage is fed from the DC power source line to the power feed port.

A heat management apparatus comprises a first heat exchange portion, a second heat exchange portion and a throttle unit, wherein the first heat exchange portion is used for exchanging heat between a refrigerant throttled by the throttle unit, and a cooling liquid; and a first wall of the first heat exchange portion and a second wall of the second heat exchange portion are arranged opposite each other, such that the structure of the heat management apparatus is relatively compact.

A heat management apparatus comprises a first heat exchange portion, a second heat exchange portion and a throttle unit, wherein the first heat exchange portion is used for exchanging heat between a refrigerant throttled by the throttle unit, and a cooling liquid; and a first wall of the first heat exchange portion and a second wall of the second heat exchange portion are arranged opposite each other, such that the structure of the heat management apparatus is relatively compact.

Provided is a refrigeration machine provided with: a refrigeration cycle having a compressor, a condenser, an expander, an evaporator, and piping (12) which sequentially connects the compressor, the condenser, and the expander; and an acoustic device (13) having a space formation section (14) which has one end (14a) connected to the piping (12) and in which a space is formed, the acoustic device (13) also having a vibration body (20) which is affixed integrally to the other end of the space formation section (14) and which has a lower natural frequency than the space formation section (14).

Provided is a refrigeration machine provided with: a refrigeration cycle having a compressor, a condenser, an expander, an evaporator, and piping (12) which sequentially connects the compressor, the condenser, and the expander; and an acoustic device (13) having a space formation section (14) which has one end (14a) connected to the piping (12) and in which a space is formed, the acoustic device (13) also having a vibration body (20) which is affixed integrally to the other end of the space formation section (14) and which has a lower natural frequency than the space formation section (14).