Abstract: A scroll compressor (CP) in which the cylinder oil circulation rate of lubricant is optimized during the operation to improve the compression efficiency is provided. In the scroll compressor (CP) having a stepped shape, the cylinder oil circulation rate of lubricant taken into the scroll compressor (CP) and circulated together with refrigerant is set to fall within the range from 1% or more to 10% or less.

Abstract: A multi-stage compressor is provided that reliably prevents liquid compression in a higher stage compression mechanism and also prevents compression efficiency degradation resulting from overheating of injection refrigerant and from the lubricating oil being raised up together with the injection refrigerant. An injection circuit is branched into a plurality of circuits. A first circuit thereof is communicatively connected to an inside space of a closed housing that is at the same side as the higher stage compression mechanism with respect to an electric motor, and a second circuit is communicatively connected to an inside space of the closed housing that is opposite from the higher stage compression mechanism with respect to the electric motor. The first circuit and the second circuit are provided with a switching mechanism for switching the injection circuit to the first circuit or the second circuit according to the dryness of the injection refrigerant.

Abstract: In a compressor provided with two compression mechanisms of a rotary type compression mechanism and a scroll type compression mechanism, torque fluctuations are reduced. The compressor 1 includes a hermetic housing 2, a low stage-side compression mechanism 3 and a high stage-side compression mechanism 4 provided in the hermetic housing 2; and an electric motor 21 for driving the low stage-side compression mechanism 3 and the high stage-side compression mechanism 4. The low stage-side compression mechanism 3 is a rotary type compression mechanism, and the high stage-side compression mechanism 4 is a scroll type compression mechanism. The suction shutoff of the scroll type compression mechanism is accomplished when a rotor 34 of the rotary type compression mechanism is at a position A corresponding to the bottom dead center, at a position B of being rotated through 90 degrees from the bottom dead center, or between the positions A and B.

Abstract: There is provided a compressor capable of feeding lubricating oil to a blade of a rotary type compression mechanism even if the oil level in an oil reservoir lowers. The compressor 1 includes a low stage-side rotary type compression mechanism 3 having a rotor 34, and a blade 38 reciprocating with the rotation of the rotor 34 while the tip end thereof is in contact with the rotor 34; a high stage-side scroll type compression mechanism 4 for sucking and compressing refrigerant gas compressed by the low stage-side rotary type compression mechanism 3; a positive displacement lubrication pump 60 for feeding lubricating oil 27 to the high stage-side scroll type compression mechanism 4; and an oil feeding path for feeding the lubricating oil 27, which is fed to the high stage-side scroll type compression mechanism 4, toward the blade 38 of the low stage-side rotary type compression mechanism 3.

Abstract: To provide a multistage compressor including an injection circuit, which can continue high-efficiency and high-capacity operations even if the injection circuit is turned on/off in accordance with operating conditions. A multistage compressor includes a high stage side compressing mechanism suctioning the intermediate pressure refrigerant gas compressed with a low stage side compressing mechanism to perform two-stage compression, and an injection circuit for injecting an intermediate pressure refrigerant into the intermediate pressure refrigerant gas suctioned to the high stage side compressing mechanism, the high stage side compressing mechanism including a capacity control mechanism for bypassing a refrigerant gas that is being compressed to a suction side, the injection circuit including an on/off mechanism for performing on/off control of refrigerant injection, and the capacity control mechanism and the on/off mechanism being operated in conjunction with each other.

Abstract: A crankshaft is to be provided that allows its assembly process to be simplified, work hours required for the assembly process to be shortened and a manufacturing cost to be reduced. The crankshaft is provided with first eccentric section and second eccentric section at respective ends while interposing a shaft section therebetween and has such a shape that a peripheral edge of the first eccentric section and/or the second eccentric section is positioned radially inside of a peripheral edge of the shaft section.

Abstract: A storage device includes a drive selection section (1), a hard disk drive (HDD) (2), and a non-volatile memory drive (3). When an instruction such as a data I/O instruction is issued from a host such as a CPU (5) and an ATA controller (6) to the hard disk drive (HDD) (2), the drive selection section (1) receives the address value. If the address value is included in the address space predefined, the non-volatile memory drive (3) is made to execute the instruction. Otherwise, the hard disk drive (HDD) (2) is made to execute the instruction.