Fujitsu General Limited

Toshiyuki Fuji

Takashi Sugiyama

Junya Tanaka

Kazuya Funada

Kenji Komine

Atsushi Itagaki

Shunji Itakura

Ken Horiguchi

Sota Shimada

Hiroshi Abiko

A rotary compressor includes: a closed upright cylindrical compressor housing including an upper portion provided with a discharge section of refrigerant and a body portion provided with an intake section of the refrigerant; a compression section disposed at a lower part in the compressor housing and configured to compress the refrigerant suctioned by the intake section to discharge the refrigerant from the discharge section; and a motor disposed at an upper part in the compressor housing and configured to drive the compression section. The motor has a rotor disposed on an inner side and a stator disposed on an outer side, the refrigerant is HFO1123 refrigerant or a refrigerant mixture containing the HFO1123 refrigerant, and an inner welded portion formed by welding using flux is provided within a projection area of the rotor at the upper portion of the compressor housing.

Rotary compressor and refrigeration cycle device

A heat exchanger includes: a heat transfer pipe in which refrigerant flows; and a spiral groove formed at an inner peripheral surface of the heat transfer pipe. A height of an inner wall of the groove in a radial direction of the heat transfer pipe is equal to or greater than 0.1 [mm], and when a wetted edge length of the heat transfer pipe is S, an inclination angle between a pipe axis direction of the heat transfer pipe and a longitudinal direction of the groove in a section of the heat transfer pipe parallel with the pipe axis direction is &#x3b8;, and a length of the heat transfer pipe is L, the inclination angle &#x3b8; is an acute angle, and a wetted area S&#xd7;L/cos &#x3b8; of the heat transfer pipe satisfies S&#xd7;L/cos &#x3b8;&#x2265;0.5 [m2].

Heat exchanger and refrigeration cycle device

A heat pump apparatus includes: a refrigerant circuit which includes a compressor, an utilization-side heat exchanger, a first expansion valve, and an outdoor heat exchanger; an injection pipe which includes a solenoid switching valve and a second expansion valve; and an objective supercooling degree table which stores objective supercooling degrees according to condensing pressure in the refrigerant circuit and rotation number of the compressor. In the heat pump apparatus, liquid refrigerant is injected to the compressor by way of the injection pipe. The heat pump apparatus switches between a first case where the liquid refrigerant is injected to the compressor and a second case where the liquid refrigerant is not injected, and a value of the objective supercooling degree is changed between the first case and the second case to control the first expansion valve based on the value of the objective supercooling degree.

Heat pump apparatus using supercooling degree to control expansion valve

A heat pump apparatus includes: a refrigerant circuit which includes a compressor, a utilization-side heat exchanger for exchanging heat between water and refrigerant, an electronic expansion valve, and an outdoor heat exchanger; a controller which controls the compressor and the electronic expansion valve; a subcooling value calculating unit which calculates a subcooling value of the refrigerant circuit; a condensing pressure detector which detects condensing pressure of the compressor; a compressor rotation number detector which detects rotation number of the compressor; and an objective subcooling value extracting unit which selects and extracting an objective subcooling value stored in advance, from the condensing pressure and the rotation number of the compressor. The controller adjusts an opening degree of the electronic expansion valve so that the calculated subcooling value of the refrigerant circuit reaches the objective subcooling value.

Growing community of inventors

Kanagawa, Japan

Toshiyuki Fuji