Refrigerating device and environmental testing apparatus

Abstract

A refrigerating device includes a refrigerating circuit and a control portion. The refrigerating circuit includes a main flow path in which a compressor, a condenser, an expansion portion, and an evaporator are connected to each other, and a bypass flow path that connects a discharge side of the condenser and a suction side of the compressor, and a flow rate control portion is provided in the bypass flow path. The control portion is configured to set a target temperature of a coolant introduced into the compressor according to a pressure of the coolant on the suction side of the compressor and is configured to change an opening degree of the flow rate control portion such that a temperature of the coolant introduced into the compressor becomes the target temperature. The target temperature when the pressure is high is higher than that when the pressure is low.

What is claimed is: 
     
         1 . A refrigerating device comprising a refrigerating circuit and a control portion configured to control the refrigerating circuit, wherein
 the refrigerating circuit includes a main flow path in which a compressor, a condenser, an expansion portion, and an evaporator are connected to each other and in which a coolant undergoing a phase change is to be circulated, and a bypass flow path that connects a discharge side of the condenser and a suction side of the compressor, and a flow rate control portion whose opening degree is adjustable is provided in the bypass flow path,   the control portion is configured to set a target temperature of the coolant introduced into the compressor according to a pressure of the coolant on the suction side of the compressor and is configured to change the opening degree of the flow rate control portion such that a temperature of the coolant introduced into the compressor becomes the target temperature, and   the target temperature when the pressure is high is higher than that when the pressure is low.   
     
     
         2 . A refrigerating device comprising a refrigerating circuit and a control portion configured to control the refrigerating circuit, wherein
 the refrigerating circuit includes a main flow path in which a compressor, a condenser, an expansion portion, and an evaporator are connected to each other and in which a coolant undergoing a phase change is to be circulated, and a bypass flow path that connects a discharge side of the condenser and a suction side of the compressor, and a flow rate control portion whose opening degree is adjustable is provided in the bypass flow path,   the control portion is configured to set a target temperature of the coolant introduced into the compressor according to a requirement level of a refrigerating capacity and is configured to change the opening degree of the flow rate control portion such that a temperature of the coolant introduced into the compressor becomes the target temperature, and   the target temperature when the requirement level is high is higher than that when the requirement level is low.   
     
     
         3 . A refrigerating device comprising a refrigerating circuit and a control portion configured to control the refrigerating circuit, wherein
 the refrigerating circuit includes a main flow path in which a compressor, a condenser, an expansion portion, and an evaporator are connected to each other and in which a coolant undergoing a phase change is to be circulated, and a bypass flow path that connects a discharge side of the condenser and a suction side of the compressor, and a flow rate control portion whose opening degree is adjustable is provided in the bypass flow path,   the control portion is configured to set a target temperature of the coolant introduced into the compressor according to an amount of the coolant sucked into the compressor and is configured to change the opening degree of the flow rate control portion such that a temperature of the coolant introduced into the compressor becomes the target temperature, and   the target temperature when the amount of the sucked coolant is large is higher than that when the amount of the sucked coolant is small.   
     
     
         4 . The refrigerating device according to  claim 1 , wherein
 the target temperature is to change in a certain range of change rate.   
     
     
         5 . The refrigerating device according to  claim 1 , wherein
 the target temperature changes in a certain range of change rate when any one of conditions below is in a first region of a predetermined value or less, and the target temperature changes at a change rate more than the certain range of change rate when any one of the conditions below is in a second region of more than the predetermined value, the conditions including   (1) a pressure of the coolant on the suction side of the compressor,   (2) a requirement level of a refrigerating capacity, and   (3) an amount of the coolant sucked into the compressor.   
     
     
         6 . An environmental testing apparatus comprising the refrigerating device according to  claim 1 . 
     
     
         7 . An environmental testing apparatus comprising the refrigerating device according to  claim 2 . 
     
     
         8 . An environmental testing apparatus comprising the refrigerating device according to  claim 3 .