| 摘要 |
<p>An object is to provide a two-stage expansion refrigerating device capable of performing control with low cost so that a pressure of a refrigerant which has flowed through a high-pressure-side expansion unit (3) is an optimum pressure, the device comprises a control unit (50) (a controller) which controls a compressor (1) (a low-stage-side compression element and a high-stage-side compression element) and each expansion unit (3,5) (a high-pressure-side expansion valve (3) as a high-pressure-side expansion unit and a low-pressure-side expansion valve (5) as a low-pressure-side expansion unit), and a temperature sensor (52) (a temperature detection unit) which detects a temperature of the refrigerant which has flowed through the high-pressure-side expansion valve (3), and the controller (50) estimates a pressure of the refrigerant which has flowed through the high-pressure-side expansion valve based on a temperature detected by the temperature sensor (52), and controls one of the high-pressure-side expansion valve (3) and the low-pressure-side expansion valve (5) based on the estimated pressure.</p> |
