Hitachi, Ltd.

Hitachi Air Conditioning Systems Co., Ltd.

Hitachi, Ltd., Trustee, for the Benefit of Hitachi Air Conditioning Systems Co., Ltd.

Akira Saruta

Susumu Nakayama

Kazumoto Urata

Hiroaki Tsuboe

Kenji Tojo

Satoshi Kikuchi

Mutsunori Matsunaga

Atsuhiko Yokozeki

Katsutoshi Nii

Kazuhiko Kawaike

Kengo Hasegawa

Masaharu Senoo

Kooji Aizawa

Masanori Yoshizaki

Ryoichi Nakashima

Koichi Teshirogi

Keizi Noma

Kouei Yaegashi

A refrigerating device including a refrigerating cycle including a plurality of compressors driven by motors, the plurality of compressors comprising a variable speed compressor which can be controlled in capacity and a constant speed compressor which is driven by a motor of which rotor core comprising a cage type conductor and permanent magnets.

Refrigerating device

A refrigerating machine having a compressor driven by a motor. The motor incorporates an armature with an iron core having a cage type conductor and a permanent magnet which is magnetized so as to enable the motor to operate as a synchronous motor. A bypass passage is provided between a discharge side of the compressor and a suction side of the compressor, a shut-off valve is provided for opening and closing the bypass passage, a pressure detecting device is provided for detecting a discharge pressure from the compressor and a current detector is provided for detecting a value of drive current for the compressor. The shut-off valve is opened and closed in accordance with the discharge pressure and the value of the drive current.

Refrigerating machine

A refrigerating machine includes a plurality of compressors driven by motors each having an armature core incorporating a squirrel cage conductor and a permanent magnet which is magnetized so as to allow the motor to serve as a synchronous motor, and a compressor drive circuit for selectively driving the motor at a power source frequency by a commercial power source or at a variable frequency by an inverter. Thus, the overall efficiency of the refrigerating machine can be enhanced.

An air-conditioner, an outdoor unit and an refrigeration device each using a refrigeration cycle which can reduce power consumption so as to be highly efficient, which can be operated by a commercially available power source, and which is highly reliable. An air-conditioner comprises a motor and a refrigeration cycle including a compressor driven by the motor, an outdoor heat-exchanger and an indoor heat-exchanger, the motor being located in a motor chamber within a closed container, and refrigerant gas in the refrigeration cycle flows through the motor chamber, wherein the motor has a core of a rotor in which a cage type conductor and permanent magnets magnetized in bipolar state are embedded, and said motor is driven by a commercially available electric power source.

Air-conditioner, outdoor unit and refrigeration unit

A thrust bearing including a ring-like form plate body, and a plurality of rib members provided on the ring-like form plate body of the thrust bearing. Such a plurality of rib members may be provided on a thrust runner. The rib members cause a difference in load deformation amount in a circumferential direction according to thrust load and generate a wedge-shaped form clearance between a sliding face of the thrust bearing and a sliding face of the thrust runner. Since the wedge-shaped form clearance is formed by utilizing the load deformation, even when the thrust load becomes large, the wedge-shaped form clearance does not become narrow. The occurrence of dynamic pressure by the wedge effect and the formation of a water film can be assured, and the temperature increase between the sliding face of the thrust runner and the sliding face of the thrust bearing can be restrained.

Submersible thrust bearing apparatus

A novel rotor construction is disclosed, in which plural permanent magnets are arranged on the outer periphery of a rotor core, which are protected with a cover, and in which a member is placed at an axial end of the rotor core cast with end rings with a balance weight on the outside thereof. The protective cover protects the outer peripheries of the end rings and dampens the centrifugal force of the balance weight. Projections provided on the outer periphery of the member are located at the center of the permanent magnets to reduce the leakage magnetic fluxes between the permanent magnets.

Reinforced permanent magnet rotor with cast zinc

Growing community of inventors

Chiba, Japan

Akira Saruta