Low-temperature refrigeration device arranged in a frame and comprising a working circuit forming a loop and containing a working fluid, the working circuit forming a cycle comprising in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, the device comprising a refrigeration heat exchanger intended to extract heat from at least one member by exchanging heat with the working fluid, the mechanisms for cooling and reheating the working fluid comprising a common heat exchanger in which the working fluid transits in counter-flow in two separate transit portions of the working circuit, the compression mechanism comprising at least two compressors and at least one motor for driving the compressors, the working fluid expansion mechanism comprising at least one rotary turbine, the device comprising at least one drive motor comprising a drive shaft, one end of which drives a compressor and the other end of which is coupled to a turbine, the motor being attached to the frame at at least one fixed point, the common heat exchanger being attached to the frame at at least one fixed point, the two counter-flow transit portions of the common heat exchanger being orientated in a longitudinal direction of the frame, the drive shaft of the drive motor being orientated in a direction parallel or substantially parallel to the longitudinal direction and the turbine and the compressor being arranged relatively longitudinally such that the turbine is located longitudinally on the side corresponding to the relatively cold end of the common heat exchanger when the device is being operated and the compressor is located longitudinally on the side corresponding to the relatively hot end of the common heat exchanger when the device is being operated.

Disclosed is a low-temperature refrigeration device which is arranged in a frame and comprises a working circuit that forms a loop and contains a working fluid, the working circuit forming a cycle comprising, connected in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, wherein the mechanisms for cooling and heating the working fluid comprise a common heat exchanger in which the working fluid flows in opposite directions in two separate transit portions of the working circuit, the device further comprising a refrigeration heat exchanger for extracting heat from at least one member by exchanging heat with the working fluid flowing in the working circuit, the compression mechanism comprising two separate compressors, the mechanism for cooling the working fluid comprising two cooling heat exchangers which are arranged respectively at the outlet of the two compressors and ensure heat exchange between the working fluid and a cooling fluid, wherein the frame extends in a longitudinal direction and comprises a lower base intended to be mounted on a support, the cooling heat exchangers are located in the frame about the common heat exchanger, i.e. the cooling heat exchangers are not located below the common heat exchanger between the common heat exchanger and the lower base of the frame.

An air conditioning device including a condenser configured to condense a refrigerant gas into a liquid refrigerant, an evaporator configured to phase-change the liquid refrigerant introduced from the condenser into a vapor refrigerant, a refrigerant inlet pipe connected to the evaporator and into which a refrigerant is introduced from the condenser, a capillary tube fully inserted into the refrigerant inlet pipe, and a clamping portion depressed a part of the refrigerant inlet pipe and a part of the capillary tube corresponding to the depressed part of the refrigerant inlet pipe to fix the capillary tube inside the refrigerant inlet pipe.

An air-conditioning apparatus includes a refrigerant circuit including a compressor, a strainer, and an expansion valve, and a controller configured to control the expansion valve in the refrigerant circuit. In the air-conditioning apparatus, in a case where the expansion valve is closed, the controller performs control to close the expansion valve after opening the expansion valve to cause an opening port diameter of the expansion valve to be greater than a mesh diameter of the strainer.

A refrigerant cycle system includes a primary-side cycle that circulates a first refrigerant, a secondary-side cycle that circulates a second refrigerant, and a cascade heat exchanger that exchanges heat between the first refrigerant and the second refrigerant. The primary-side cycle includes a primary-side connection pipe. The secondary-side cycle includes a secondary-side connection pipe. The primary-side connection pipe includes a primary-side gas connection pipe and a primary-side liquid connection pipe. The secondary-side connection pipe includes a secondary-side gas connection pipe and a secondary-side liquid connection pipe. The pipe diameter of the secondary-side gas connection pipe is smaller than the pipe diameter of the primary-side gas connection pipe, or the pipe diameter of the secondary-side liquid connection pipe is smaller than the pipe diameter of the primary-side liquid connection pipe.

This air conditioner performs a cooling operation and a heating operation in parallel with each other with an outdoor unit and indoor units connected together through two communication pipes. The air conditioner includes a switching mechanism changing the directions of refrigerants flowing through the communication pipes depending on whether a heating dominant operation is being performed in a first load region where a cooling load is relatively light or a second load region where the cooling load is heavier than in the first load region. In the second load region, the switching mechanism allows a low-pressure refrigerant to flow from the indoor units to the outdoor unit through the second communication pipe thicker than the first communication pipe to reduce a performance deterioration due to the pressure loss involved with the heating dominant operation.

A system for cryocooling an optical sensor on a satellite to a temperature below 200K with minimal vibration comprising a miniature conical rotary screw compressor comprising an inner element configured to only rotate around a first stationary axis and an outer element configured to only rotate around a second stationary axis so that both elements revolve with minimal vibration; with at least one of a) a length of at least one of the inner element and the outer element is between 10 mm and 100 mm; b) a diameter of at least one of the inner element and the outer element is between 2 mm and 45 mm; c) a compression ratio of the rotary screw compressor is between 1:2 and 1:20; and d) a shaft speed of the conical rotary screw compressor is between 1001 and 20000 revolutions per minute.

The pressure reducing device (4) for a cooling system according to the present invention is equipped with: a pressure reducing valve (5) that is disposed in a stage subsequent to a condenser for a refrigerant (40); and a microscopic bubble formation unit (20) that is disposed within the flow path for the refrigerant from the condenser to a heat exchanger so as to form the vapor phase (41) of the refrigerant (40) into microscopic bubbles (41a) and disperse the microscopic bubbles into the liquid phase (42) of the refrigerant.

There is provided refrigeration system (1) and method for remote cooling of a thermal load having a first portion (27) and a second portion (25). The system comprises a cold source (4) having a first cooling stage (5) and a second cooling stage (6), the temperature of the first cooling stage being higher than the temperature of the second cooling stage. The system also comprises a cryogen circuit for circulation of a cryogen flow in a closed cycle, the closed cycle being thermally coupled to the cold source. The system further comprises a compressor (7) for compressing and circulating the cryogen flow in the cryogen circuit. The cryogen circuit comprises a first conduit for thermally connecting the first cooling stage of the cold source to the first portion of the thermal load so as to cool said first portion towards the temperature of the first cooling stage, and a second conduit for thermally connecting the second cooling stage of the cold source to the second portion of the thermal load so as to cool said second portion to wards the temperature of the second cooling stage. The cryogen flow in the system is a sub-cooled or saturated liquid, two phase, saturated or overheated, supercritical gas helium flow.

The invention relates to a refrigerant circuit (10) of a vehicle air-conditioning system (12), in particular for electric vehicles, comprising a compressor unit (14) which includes a first compressor (16) and a second compressor (18) arranged downstream for compressing a refrigerant (20), a condenser (22) for heating air (24) which can be supplied to a vehicle interior, a first pressure reducing unit (26) arranged downstream of the condenser (22) for decompressing the refrigerant (20) from the condenser (22), a heat exchanger (28) through which refrigerant flows for heat exchange with vehicle ambient air (30), an evaporator (32) for cooling air (24) which can be supplied to a vehicle interior, and a second pressure reducing unit (34) arranged upstream of the evaporator (32) for decompressing the refrigerant (20) from the heat exchanger (28), the second compressor (18), the condenser (22) and the first pressure reducing unit (26) being bypassed in a cooling mode of the vehicle air-conditioning system (12), and the evaporator (32) and the second pressure reducing unit (34) being bypassed in a heating mode of the vehicle air-conditioning system (12). The invention furthermore relates to a method of air-conditioning a vehicle interior, in particular by means of the refrigerant circuit (10) described above.