Air conditioner and flow path switching valve

Abstract

An air conditioner includes two cut-off valves connected to respective refrigerant flow paths. At least one of the two cut-off valves is configured as a flow path switching valve configured to switch a flow path so as to block the refrigerant flow paths when a refrigerant leaks in a utilization circuit.

1 . An air conditioner comprising:
 a refrigerant circuit that includes a heat source circuit to which a compressor and a heat source heat exchanger are connected, and includes a utilization circuit to which a utilization heat exchanger is connected, and that is configured to perform a refrigeration cycle,   the refrigerant circuit further including: two refrigerant flow paths connected to respective ends of the utilization circuit, and   two cut-off valves connected to the respective refrigerant flow paths, wherein   at least one of the cut-off valves is configured as a flow path switching valve configured to switch a flow path so as to block the refrigerant flow paths when a refrigerant leaks in the utilization circuit.   
     
     
         2 . The air conditioner of  claim 1 , wherein
 the refrigerant flow paths include respective first flow paths formed between the flow path switching valve and the heat source circuit, and respective second flow paths formed between the flow path switching valve and the utilization circuit, and   the flow path switching valve is configured as a four-way switching valve having a first port connected to associated one of the first flow paths, a second port connected to associated one of the second flow paths, a third port, and a fourth port.   
     
     
         3 . The air conditioner of  claim 2 , wherein
 the refrigerant circuit further includes a high-pressure introduction circuit configured to introduce a high-pressure refrigerant in the first flow paths into the third port, and   the four-way switching valve is of a differential pressure drive type using the high-pressure refrigerant introduced into the third port as a drive source.   
     
     
         4 . The air conditioner of  claim 3 . wherein
 the refrigerant circuit is configured to perform a first refrigeration cycle in which the heat source heat exchanger serves as a radiator and the utilization heat exchanger serves as an evaporator, and a second refrigeration cycle in which the utilization heat exchanger serves as a radiator and the heat source heat exchanger serves as an evaporator, and   the high-pressure introduction circuit is configured to introduce at least the high-pressure refrigerant in the first flow path having higher pressure out of the two first flow paths of the refrigerant flow paths into the third port.   
     
     
         5 . The air conditioner of  claim 4 , wherein
 the high-pressure introduction circuit includes
 a liquid-side introduction path for allowing the first flow path of the refrigerant flow path on a liquid side to communicate with the third port, 
 a gas-side introduction path for allowing the first flow path of the refrigerant flow path on a gas side to communicate with the third port, and 
   the liquid-side introduction path is provided with a first on-off valve that is open during the first refrigeration cycle, and   the gas-side introduction path is provided with a second on-off valve that is open during the second refrigeration cycle.   
     
     
         6 . The air conditioner of  claim 3 , wherein
 the four-way switching valve has a fourth port that is closed,   the four-way switching valve in a first state makes the first port and the second port communicate with each other, and the third port and the fourth port communicate with each other, and   the four-way switching valve in a second state makes the first port and the third port communicate with each other, and the second port and the fourth port communicate with each other.   
     
     
         7 . The air conditioner of  claim 2 , wherein
 the four-way switching valve includes a low-pressure pipe that communicates with the utilization circuit, and is switched to a second state by differential pressure between the high-pressure refrigerant and internal pressure of the low-pressure pipe.   
     
     
         8 . The air conditioner of  claim 1 , wherein
 the refrigerant flow paths include respective first flow paths formed between the flow path switching valve and the heat source circuit, and respective second flow paths formed between the flow path switching valve and the utilization circuit,   the flow path switching valve is of an electric rotary-type and has a first port connected to associated one of the first flow paths, a second port connected to associated one of the second flow paths, a rotating portion in which an internal flow path is formed, and an electric motor configured to rotatably drive the rotating portion, and   the rotating portion of the flow path switching valve is placed at a rotational angle position of a first state in which the first port and the second port communicate with each other via the internal flow path, and is placed at a rotational angle position of a second state in which the first port and the second port are closed.   
     
     
         9 . The air-conditioning system of  claim 8 , wherein
 the flow path switching valve is configured as a three-way switching valve of an electric rotary type and has a third port that is closed, and   the rotating portion of the three-way switching valve in the first state is placed at a rotational angle position at which the first port and the second port communicate with each other via the internal flow path, and   the rotating portion of the three-way switching valve in the second state is placed at a rotational angle position at which one of the first port or the second port communicates with the third port via the internal flow path, and the other one of the first port or the second port is closed with the rotating portion.   
     
     
         10 . The air conditioner of  claim 1 , wherein
 the flow path switching valve is connected to at least the refrigerant flow path on a gas side, out of the two refrigerant flow paths.   
     
     
         11 . A flow path switching valve that is a flow path switching valve connected to a refrigerant flow path of the air conditioner of  claim 1 .