Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi, Ltd.

Minako Kanada

Kotaro Chiba

Masahiko Takano

Takeshi Tsuchiya

Masanao Kotani

Ryoji Kawai

Kenji Morita

Yoshitaka Takeuchi

Kentaro Yamamoto

Shigeyuki Yorikane

Sachio Sekiya

Toshikazu Harashima

Kosuke Sadakata

A screw compressor includes a screw rotor, a casing, and a fluid supply portion to supply fluid in a membrane form into a compression chamber in the casing. The screw rotor has a male and female rotors. A male bore covering the male rotor and a female bore covering the female rotor are formed on the inner surface of the casing. An intersection line, on a higher pressure side, of the male and female bores is defined as a compression cusp. In a bore development view, a trajectory made by the first intersection of an extension line of a female lobe ridge and a male lobe ridge being moved, along with the rotation of the male and female rotors, is defined as a trajectory line. An opening of the fluid supply section to the compression chamber is positioned between the compression cusp and the trajectory line.

Screw compressor having an opening of a fluid supply portion between the compression intersection line and a trajectory line

Provided is a fluid machine configured such that liquid supplied to a working chamber from the outside of the fluid machine is dispersed extensively in the working chamber. This fluid machine is constituted of a screw rotor and a casing for accommodating the screw rotor and is provided with a liquid supply section for supplying liquid into a working chamber from the outside. The liquid supply section is configured so that liquid is dispersed in the longitudinal direction of the tooth groove of the screw rotor rather than in the width direction thereof.

Fluid machine

Provided is an air compressor which helps to attain a proper discharge air temperature and which is superior in energy saving property. There are provided an air line connecting an air compressor, an oil separator, and an after cooler; an oil circulation line connecting the air compressor, the oil separator, and an oil cooler; a bearing oil supply line connecting one end of an intermediate branching portion disposed at an intermediate point of the oil circulation line between the oil cooler and the air compressor to a bearing oil supply portion of the air compressor; an intermediate portion oil supply line connecting the other end of the intermediate branching portion to an intermediate oil supply portion of the air compressor; a branching line supplying oil to the bearing oil supply portion and the intermediate oil supply portion; a blower sending air to the oil cooler and the after cooler; a bypass line connecting one end of a bypass branching portion disposed at an intermediate point of the oil circulation line between the oil separator and the oil cooler to the downstream side of the oil cooler of the bearing oil supply line; and a control valve controlling the inflow amount of the lubricating oil to the bypass line.

Air compressor

Growing community of inventors

Tokyo, Japan

Minako Kanada