Refrigeration cycle

摘要

To present a refrigeration cycle of high reliability by controlling, in a refrigeration cycle, deposit of foreign matter at inlet or outlet of a capillary tube in a simple and inexpensive structure, regardless of changeover of cooling operation and heating operation. In a refrigeration cycle using an alternative refrigerant, a junction 3b of a capillary tube 3a composing an expansion device 3 and a piping 5 has a slope 6 gradually decreased in inside diameter from the piping 5 side to the capillary tube 3a side. An end portion of the capillary tube 3a projects into the junction 3b at the piping 5 side. The projecting end of the capillary tube 3a is opened obliquely to the axial line of the capillary tube. A hole is formed in the peripheral wall of the projecting end of the capillary tube 3a. In such constitution, foreign matter in the refrigerant is forced to deposit in other portions than the capillary tube 3a, and the foreign matter is removed from the refrigerant. At the same time, the depositing foreign matter is prevented from having effects on the flow of the refrigerant.