Scroll type compressor and refrigeration cycle using the same

Abstract

A scroll type compressor having a pair of scroll type compression units which are encased in the same casing so as to make a common use of a lubricating oil reservoir provided in the casing, wherein the compression units have compression elements, drive shafts, driving motors and other components which are of the same constructions and specifications, and wherein each of the compression units are adapted to be driven selectively by commercial electrical power or through a frequency-variable inverter so as to operate at different speeds. Since both compression units can be made up from the same components such as the compression elements, loads in the production, service and administration, are greatly reduced contributing to a reduction in the labor and cost, while eliminating any mounting error. Various operation patterns are obtainable by selecting the combination of the direct commercial power and the power supplied through the inverters, so as to provide delicate control of refrigeration capacity over a wide range in accordance with the level of the load demand. Common use of the lubricating oil reservoir by both compression units eliminates necessity for specific measure for preserving oil levels equally for both compression units.