Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.