Search International and National Patent Collections
|1. (WO2018079731) REFRIGERATION DEVICE|
|Applicants:||DAIKIN INDUSTRIES, LTD.
Provided is a refrigeration device that can reduce, to be small, deficiency/excess differences in the amount of refrigeration machine oil between compressors in the case where a plurality of compressors are connected in parallel. The present invention comprises: a plurality of parallel-connected compressors (21a, 21b, 21c) that include at least one inverter compressor (21a); an oil separator (23) that is provided on the discharge sides of the plurality of compressors; refrigerant supply pipes (30, 30a, 42) that supply a refrigerant to the plurality of compressors; an oil return pipe (38) that connects the oil separator and the refrigerant supply pipes to each other; and a controller (70). The controller performs one or both of the following control operations: when a first prescribed condition is satisfied, the rotation frequency of the inverter compressor (21) is reduced, and as a result, a greater amount of refrigeration machine oil is returned to the compressors (21b, 21c) other than the inverter compressor the rotation frequency of which has been reduced; when a second prescribed condition is satisfied, relative flow rate adjustment degrees are changed among a plurality of flow rate adjustment valves (33a, 33b, 33c), which are provided in the refrigerant supply pipes (30, 30a, 42) so as to respectively correspond to the intake sides of the plurality of compressors, namely between the flow rate adjustment valve (33a) provided so as to correspond to the inverter compressor and the other flow rate adjustment valves (33b, 33c), and as a result, greater amounts of refrigeration machine oil are returned to the compressors other than the inverter compressor.