Decompression device

A decompression device for decompressing a high-pressure refrigerant of a refrigerant cycle, the decompression device comprising:

• a body portion having a block shape;
• an upstream throttle portion provided in the body portion at an upstream side of a refrigerant flow;
• a middle passage portion provided in the body portion at a downstream side of the upstream throttle portion such that the refrigerant having passed through the upstream throttle portion flows through the middle passage portion;
• a downstream throttle portion arranged as a fixed throttle in the body portion at a downstream side of the middle passage portion such that the refrigerant having passed through the middle passage portion flows into the downstream throttle portion, wherein
• a refrigerant passage defined from the upstream throttle portion to the downstream throttle portion through the middle passage portion has at least a bent portion in which the refrigerant flow is bent,
• the upstream throttle portion includes an upstream throttle passage in which the refrigerant is decompressed and expanded, and a valve body having an open degree adjusting portion configured to adjust an open degree of the upstream throttle passage,
• the upstream throttle portion is configured by a variable throttle having a valve chamber in which the valve body is slidably accommodated,
• the valve body is provided with a partition portion that divides the valve chamber into an inlet-side pressure chamber and a middle-side pressure chamber,
• the inlet-side pressure chamber is provided to communicate with an inlet side refrigerant passage and the upstream throttle passage so that the refrigerant from the inlet side refrigerant passage flows into the upstream throttle passage through the inlet-side pressure chamber,
• the middle-side pressure chamber communicates with the middle passage portion through a pressure equalization portion such that the refrigerant flows into the middle-side pressure chamber from the middle passage portion, and
• the valve body is configured to cause the partition portion to be displaced in accordance with a pressure difference between the inlet-side pressure chamber and the middle-side pressure chamber, so that the open degree adjusting portion adjusts the open degree of the upstream throttle passage.