Daikin Industries, Ltd.

Hiroto Nakajima

Takeo Ueno

Masaaki Takegami

Satoru Sakae

Koichi Kita

Kouichi Kita

Tetsuya Suda

Seiki Inoue

Seiji Sakai

For the supply of refrigeration oil accumulated in an oil return compressor () into a higher stage compression mechanism (), an oil sump in a discharge pressure space defined in the casing of the oil return compressor () and the downstream side of an oil separator () are connected together through an oil return passageway (). And, a pressure reducing means () for the reduction in pressure of refrigerant flowing towards the oil separator () from the oil return compression mechanism () is disposed in place between the oil return compressor () and the oil separator () in a discharge pipe () of a lower stage compression mechanism ().

Refrigeration apparatus

In a refrigerant circuit (), a refrigerator circuit () and a freezing circuit () are connected in parallel to an outdoor circuit (). In the freezing circuit (), a freezer circuit () and a booster circuit () are connected in series. A booster compressor () and a four-way switch valve () are provided in the booster circuit (). During the time when a freezer heat exchanger () performs cooling operation for cooling the inside air, refrigerant evaporated in the freezer heat exchanger () is compressed in the booster compressor (), and then, is sucked into a variable capacitance compressor (). On the other hand, during defrosting of the freezer heat exchanger (), the refrigerant evaporated in a refrigerator heat exchanger () is compressed in the booster compressor (), and then, is supplied to the freezer heat exchanger (). The refrigerant condensed in the freezer heat exchanger () during the defrosting operation is sent back to the refrigerator heat exchanger ().

Freezing device

Operation control apparatus for air conditioner

Operation control device for air conditioner

System for controlling operation of refrigeration device

Growing community of inventors

Osaka, Japan

Hiroto Nakajima