Refrigerating cycle apparatus with a compressor having simultaneously

Abstract

A refrigerating cycle apparatus has, in a sealed casing, a compressor including first and second compressor means driven simultaneously. A refrigerating cycle circuit is constituted by connecting this compressor, a condenser, a pressure-reducing device, and an evaporator. Counterflow checking means is provided on the suction side of the first compressor means, for checking the counterflow of the refrigerant from the first compressor means to the evaporator. Switching means is provided on the discharge side of the second compressor means. The switching means is operated such that the refrigerant gas compressed by the second compressor means is let to flow into the sealed casing to perform a parallel compression operation with use of the first and second compressor means, and the refrigerant gas compressed by the second compressor means is let to flow from the downstream side of the counterflow checking means to the suction side of the first compressor means, thereby performing a two-stage compression operation in which compression is performed first by the first compressor means and then by the second compressor means. The capacity variable range of the compressor can be increased with a simple structure including one counterflow checking means and one switching means.