Hitachi, Ltd.

Minetoshi Izushi

Hirokiyo Terada

Kensaku Oguni

Makoto Nagai

Hiroshi Takenaka

Toshio Hatada

Takao Senshu

Masaaki Itoh

Kenji Tokusa

Minoru Sato

Shunji Sasaki

Yasuji Sakuma

Masahiro Ito

Kazuhiko Kawaike

Shigekazu Nozawa

Hiromu Yasuda

Hideyuki Kimura

Masayuki Urashin

Shinichi Shimode

Yoshihiko Mochizuki

Takeo Tanaka

Masamichi Hanada

Tatsuya Sugiyama

Naoto Katsumata

Naoki Shikazono

Kimio Nagata

Sumiyoshi Takeda

Motomichi Doi

Shinya Okabe

Hiromi Tsuji

Ryouji Sato

A heat exchanger composed by overlapping a plurality of heat exchanger units each of which is formed by inserting a plurality of fins over one or a plurality of heat transfer tubes. The fins are worked so that a pair of opposed fins of the overlapped heat exchanger units are brought into contact with each other at one or more points. This heat exchanger constitutes an air conditioner when the heat exchanger units are overlapped in a direction of gravity.

Heat exchanger and air conditioner using same

An air conditioner in accordance with the invention comprises a first unit including a compressor and a heat exchanger; a second unit including a heat exchanger; a refrigerant circuit connecting the compressor and the heat exchanger of the first unit, with the heat exchanger of the second unit, through which a refrigerant flows; a refrigerant pressure reduction valve disposed in the refrigerant circuit and provided in the second unit; a control unit provided in the first unit for controlling the refrigerant pressure reduction valve in the second unit.

Air conditioner

An air conditioner comprises a first unit including a compressor and a heat exchanger, a second unit including a heat exchanger, a refrigerant circuit connecting the compressor and the heat exchanger of the first unit, with the heat exchanger of the second unit, through which a refrigerant flows, a refrigerant pressure reduction valve disposed in the refrigerant circuit and provided in the second unit, a control unit provided in the first unit for controlling the refrigerant pressure reduction valve in the second unit.

A fin-tube type heat exchanger has parallel heat transfer tubes and a stack of a plurality of plate fins mounted on the tubes. Heat exchange is conducted between a first fluid flowing through the tubes and a second fluid flowing through the stack across each of the fins. Each fin has flat tube-mounting portions spaced in the longitudinal direction of the fin and formed with tube-mounting holes and a louver section disposed between each adjacent pair of tube-mounting portions. The louver section has elongated slats extending longitudinally of the fin and having side edges each spaced from an adjacent side edge of an adjacent slat. The slats are classified into two groups in respect of the cross-sectional shape. The slats of one group have generally flat cross-sections to reduce the resistance of the fin to the flow of the second fluid through the stack and are disposed in planes offset from the plane of the tube-mounting portions. The slats of the other group have V-shaped or inverted V-shaped cross-sections to increase stiffness of the fin in the longitudinal direction thereof.

Fin-tube type heat exchanger

An active noise control system for a three-dimensional space, including noise detecting means, sound generating means, noise control effect detecting means and a control device consisting of a phase of a wave signal fed from the noise detecting means wherein a plurality of noise control effect detecting means and sound generating means are disposed at a distance shorter than a wavelength of the noise to be controlled, and input signals of the respective sound generating means and output signals of the respective noise control effect detecting means are fed through filters, separately, to control the sound for active noise control. In case of an air conditioner, the noise control effect detecting means are disposed at positions where an air stream flowing through the air conditioner is not obstructed thereby.

Active noise control apparatus for three-dimensional space

A screw compressor in which a pair of screw rotors supported by bearings and accommodated in a casing act to compress a gas and in which a slide valve disposed between an inner wall of the casing and the pair of screw rotors is capable of moving axially while maintaining a small gap between itself and the outer peripheries of the screw rotors, the rate of gas flow bypassed to an inlet port during compression being regulated by axially moving the slide valve. The screw compressor has: a side cover in which bearing for supporting the pair of screw rotors on the discharge side and a slide valve driving hydraulic means are incorporated and which is disposed on the discharge side of the screw rotors; a discharge axial port formed in the side cover; and at least one projection continuous with an opening edge of the discharge axial port and in contact with a semi-circular surface of the slide valve facing in the radial direction thereof, the projection acting to limit the radial movement of the slide valve while the slide valve is moving in contact with the top end of the projection.

Screw compressor with slide valve movement preventing structure

A screw compressor comprises a casing and a pair of male and female rotors respectively having herical teeth and grooves formed in their outer peripheries. The rotors are arranged within the casing in meshing relation to each other through the teeth and grooves. Each rotor is rotatably supported by a pair of first and second radial plain bearings and a thrust plain bearing which is arranged at an end of the rotor shaft and adjacent the second radial plain bearing. Each of the thrust plain bearings is of dynamic-pressure type in which with rotation of a corresponding one of the shafts of the respective rotors, pressure is applied to lubricant by sliding movement of the thrust plain bearing to produce an anti-thrust force. The lubricant for each of the second radial plain bearings and for a corresponding one of the thrust plain bearings is fed to a space between the second radial plain bearing and the thrust plain bearing, and is distributed to the second radial plain bearing more in amount than that fed to the thrust bearing due to a difference between flow resistance with which the lubricant passes through the second radial plain bearing and flow resistance with which the lubricant passes through the thrust plain bearing.

Screw compressor

Growing community of inventors

Shimizu, Japan

Minetoshi Izushi