Fujitsu General Limited

Takamitsu Kurokawa

Satoshi Tomioka

Takahiro Matsunaga

Tetsuya Ito

Hideya Tamura

Shintaro Sanada

There is provided a refrigeration apparatus in which a refrigerant accumulating in non-operating outdoor units is supplied to an outdoor unit being operated in which a shortage of refrigerant occurs without starting the compressors of the non-operating outdoor units. In the control method for the refrigeration apparatus in which to refrigerant pipinginstalled between the indoor side and the outdoor side, a plurality of outdoor unitsA,B each including a compressor, a directional control valve, an outdoor heat exchanger, an outdoor expansion valve, and an accumulatorare connected in parallel on the outdoor side, and each of the outdoor units is provided with a hot gas bypass circuitthat includes a solenoid valveand an expansion mechanismarranged in series, and is connected between high-pressure side pipingon the discharge side of the compressor and low-pressure side pipingon the accumulator side, if a shortage of refrigerant occurs when air cooling operation is performed in a state in which only the outdoor unitA is operated and other outdoor unitsB are not operated, the solenoid valvesof the non-operating outdoor unitsB are opened so that the refrigerant accumulating in the non-operating outdoor unitsB is supplied to the outdoor unitA via the hot gas bypass circuitand the low-pressure piping

Refrigeration apparatus

A refrigeration apparatus includes an outdoor unit having a first compressor and a second compressor connected in parallel with each other, a first oil separator attached to the first compressor and connected to a suction pipe of the second compressor via a first oil return piping including a pressure reducing device, and a second oil separator attached to the second compressor and connected to a suction pipe of the first compressor via a second oil return piping including a pressure reducing device. The suction pipes of the first and second compressors are connected together. The first compressor is a variable-speed compressor, and the second compressor is a constant-speed compressor. A solenoid valve selectively forming a bypass circuit with respect to the pressure reducing device, is connected in parallel with the pressure reducing device of the first oil return piping. The solenoid valve is opened when the first compressor is restarted.

Growing community of inventors

Kawasaki, Japan

Takamitsu Kurokawa