Hitachi, Ltd.

Hitachi Astemo Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi Automotive Systems, Ltd.

Shuhei Nagata

Masaki Koyama

Takahiro Suzuki

Wataru Hatsuse

Yasuaki Aoyama

Kenji Morita

Shigeyuki Yorikane

Kotaro Chiba

Yoshinori Kawai

Kan Kobayashi

Yuta Kajie

Shinji Seto

Takashi Ogawa

Takeshi Tsuchiya

Yosuke Tanabe

Naofumi Harada

Tomoyuki Ri

Naoyuki Oohata

A screw compressor has first and second screw rotors that suck, compress, and deliver a working medium; a first bearing supporting one end of the first screw rotor coupled to a rotating shaft of a power source; a casing housing the first screw rotor and first bearing; a shaft-sealing member located on an opposite side of a tooth profiler for the first screw rotor relative to the first bearing and seals a through hole in the casing, through which a shaft of the first screw rotor coupled to the output shaft of the power source is inserted; a partition wall isolating the first bearing from the shaft-sealing member; and a liquid-supply route that is provided in the casing and has a first liquid supply opening for supplying a lubricating liquid to the shaft-sealing member and a second liquid supply opening for supplying the lubricating liquid to the first bearing.

Screw compressor

A screw compressor for compressing a working medium sucked through a suction opening and discharging the compressed working medium through a delivery opening, wherein the screw compressor includes: a male rotor and a female rotor that rotate while meshing with each other; a casing that houses the male rotor and the female rotor and is provided with a bore which forms a working chamber designed, together with the male rotor and the female rotor, to compress the working medium; a drive unit that rotationally drives at least one of the male rotor and the female rotor; a working chamber closing unit that forms a suction port for sucking the working medium into the working chamber and closes the working chamber when the working chamber reaches a specified capacity; and a suction space that connects the suction opening and the suction port to allow communication therebetween.

Screw compressor having working chamber closing member to regulate suction working medium flow to a working chamber

Controllability of a linear motor or a compressor is improved in a linear motor system that includes: an armature having magnetic poles and winding wires; a mover having a permanent magnet; and a power conversion unit that outputs AC power to the winding wires, in which the mover and the armature are relatively movable, and the mover or the armature is connected to an elastic body. The linear motor system further includes: a position detection unit that detects and outputs the position of the mover with respect to the armature, a position estimation, or a current detection unit that outputs the value of current flowing through the winding wires; and a control unit that controls the output of the power conversion unit on the basis of the output of the position detection unit, the output of the position estimation unit, or the output of the current detection unit.

Linear motor system and compressor

Provided is a linear motor control apparatus capable of improving estimation accuracy of a resonance frequency immediately after start, and a compressor equipped with the linear motor control apparatus. A linear motor control apparatus includes a winding to which an AC voltage is applied and a mover which is connected to an elastic body, in which the linear motor control apparatus includes an operation mode (1) which monotonously increases amplitude of the AC voltage while keeping a frequency of the AC voltage substantially constant, and an operation mode (2) which changes the frequency of the AC voltage while keeping the amplitude of the AC voltage substantially constant, and executes the operation mode (1) and the operation mode (2) in this order.

Linear motor control apparatus and compressor equipped with the same

An object of the present invention is to provide a linear motor and a compressor which are effective against a non-fixed structure in which end portions of a resonant spring are not fixed and are capable of restraining loads in an up-down direction and a left-right direction which act on a slider. A linear motor includes a slider () which is driven in a first direction, a resonance spring () which is capable of vibrating in the first direction, and a permanent magnet () which is provided at the slider () and is magnetized in a second direction perpendicular to the first direction. The linear motor includes a bearing () that is movable against both forces of a force in the second direction and a force in a third direction perpendicular to the first direction and the second direction, and an elastic-body support member () which connects the resonant spring () and the bearing () to each other.

Linear motor and compressor

Provided are a power conversion device and a system using the same, which can reduce loss of each semiconductor element in a power conversion circuit and enable high efficiency of a device controlled by the power conversion device. The power conversion device includes a direct current (DC) power source; and a full-bridge circuit having first upper and lower arms having an upper element and a lower element and second upper and lower arms having an upper element and a lower element, in which the first upper and lower arms and the second upper and lower arms are electrically connectable to a device, and ON resistances of the upper element of the first upper and lower arms and the lower element of the second upper and lower arms are smaller than ON resistances of the lower element of the first upper and lower arms and the upper element of the second upper and lower arms.

Power conversion device and system using the same

Controllability of a linear motor or a compressor is improved. There is provided a linear motor system that includes: an armature having magnetic poles and winding wires; a mover having a permanent magnet; and a power conversion unit that outputs AC power to the winding wires, in which the mover and the armature are relatively movable, and the mover or the armature is connected to an elastic body. The linear motor system further includes: a position detection unit that detects and outputs the position of the mover with respect to the armature, a position estimation, or a current detection unit that outputs the value of current flowing through the winding wires; and a control unit that controls the output of the power conversion unit on the basis of the output of the position detection unit, the output of the position estimation unit, or the output of the current detection unit. In the case where a signal having a frequency substantially the same as the frequency of the AC power is applied to the output of the position detection unit, to the output of the position estimation unit, or to the output of the current detection unit, the control unit changes the frequency of the AC power, and in the case where a signal having a frequency substantially larger than the frequency of the AC power is applied, the control unit keeps the frequency of the AC power substantially the same.

In an air suspension system, starting of a compressor is facilitated in a condition in which there exists a pressure difference. There is provided an air suspension system in which air compressed by a compressor is supplied to a plurality of air chambers provided between a vehicle body side and a wheel side and configured to perform vehicle height adjustment in accordance with the supply and discharge of air. The compressor has a needle connected to a piston and extending in a moving direction of the piston, and an armature reciprocating the needle in the moving direction of the piston.

Air suspension system

Provided are: a linear motor that has increased compactness and that can effectively use magnetic flux; and an apparatus provided with the linear motor. The linear motor has a top mobile element and a bottom mobile element provided below the top mobile element, and an armature has: a top first set of magnetic pole teeth comprising two magnetic pole teeth opposing each other in the vertical direction across a space through which the top mobile element can move in a reciprocating manner; and a bottom first set of magnetic pole teeth comprising two magnetic pole teeth opposing each other in the vertical direction across a space through which the bottom mobile element can move in a reciprocating manner. The linear motor is characterized by the armature being able to be split into an inner component, which has the bottom magnetic pole tooth of the top first set of magnetic pole teeth and the top magnetic pole tooth of the bottom first set of magnetic pole teeth, and a component having approximately the same shape as that of the inner component or outer component and having the bottom magnetic pole tooth of the bottom first set of magnetic pole teeth.

Linear motor and apparatus using same

To provide a motor system that can control the position of a control object in multiple directions while suppressing the number of required switching elements. A motor system includes: a power conversion device including first, second, and third up-down arms each including two switching elements connected in series; a control object; and a first load including a magnetic pole tooth facing the control object, and a winding wound around the magnetic pole tooth. The motor system includes a second load including two magnetic pole teeth facing each other in a second direction with the control object therebetween, and a winding wound around one or both of the magnetic pole teeth. The power conversion device provides a force with respect to a first direction to the control object through an output to the first load, and provides a force with respect to the second direction to the control object through an output to the second load.

Motor system and compressor equipped therewith

A linear motor includes an armature with two magnetic poles arranged in the Z direction, and winding wires wound around the two magnetic poles, respectively, and a mover with a permanent magnet, which moves relative to the armature in the Z direction. A first auxiliary magnetic pole is disposed between the two magnetic poles, and a bridge is disposed between the first auxiliary magnetic pole and the magnetic pole. The two winding wires are electrically coupled.

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Tokyo, Japan

Shuhei Nagata