A leak-current detecting unit detects a zero-phase current flowing from an electric-motor driving device, which drives an electric motor with electric power from an alternating-current power supply, or the electric motor to a ground, a leak-current control unit that, on the basis of the zero-phase current detected by the leak-current detecting unit, generates a control signal having cyclicity synchronized with the alternating-current power supply, and an anti-phase generating unit that generates an anti-phase current that is in anti-phase to the zero-phase current on the basis of the control signal from the leak-current control unit, and outputs the anti-phase current.

An air compressor assembly may include a support structure, an operating unit including a compressor operatively connected to a motor through at least one drive belt, and at least one vibration isolator that is positioned between at least a portion of the support structure and at least a portion of the operating unit. The vibration isolator(s) is configured to dampen vibratory energy generated by the operating unit.

An electric device includes a case, an electric component that is provided in the case and has a main body section and a lead terminal extending from the main body section, the main body section being supported on the case, a circuit board that is provided in the case and has a connecting hole through which the lead terminal is inserted, and a guide member that has a guide hole positioned relative to the connecting hole, the lead terminal being disposed to penetrate through the guide hole.

A linear compressor is provided. The linear compressor may include a shell having a cylindrical shape, a shell cover that covers both open ends of the shell, a cylinder accommodated into the shell and defining a compression space for a refrigerant, a piston that reciprocates within the cylinder in an axial direction to compress the refrigerant within the compression space, a motor assembly including a motor that provides power to the piston and a stator cover that supports the motor, and resonant springs seated on the stator cover that support the piston to allow the piston to perform a resonant motion. The resonant springs may be circularly arranged at three points having a same interval around a center in an axial direction.

A denting device for forming a predetermined pattern on a surface near a discharge hole and an intake hole of a valve plate for a compressor includes: a seating jig to which the valve plate is fixed; a processing pin in which a pressing part for pressing the valve plate is formed at a distal end thereof; and a moving unit which is disposed on an upper portion of the seating jig, horizontally moves the processing pin at a constant speed while allowing the processing pin to vertically reciprocate at a constant speed, so as to form the pattern on the valve plate.

A compressor system and a method of reducing noise in the compressor system. The compressor system includes an inlet port configured to receive gas, an outlet port configured to output compressed gas, and a compressor pump connected to the inlet port via a pneumatic line and to the outlet port. The compressor pump is configured to pressurize gas input through the inlet port and to output a compressed gas through the outlet port. The compressor pump generates noise during operation of the compressor pump. The compressor system further comprises a side-branch resonator having a housing forming a cavity and an elongated member connected to the housing. The elongated member is pneumatically connected to the pneumatic line between the inlet port and the compressor pump. The side-branch resonator is configured to substantially reduce noise generated by the compressor pump, to monitor an operation of the compressor pump, or both.

According to the present invention, there is provided a compressor including: a piston reciprocated in a cylinder; a valve seat plate provided with a port through which a fluid passes along with the reciprocation of the piston; a valve provided in the valve seat plate to open/close the port; a valve receiver regulating the degree of opening of the valve; and a stress suppression member provided between the valve and the valve receiver, wherein the stress suppression member includes a valve exposing portion exposing the valve.

A pulsation control device coupling a reciprocating pump with either suction or discharge piping and having a generally spherical or cylindrical interior chamber includes a curved baffle with a pressure drop device (e.g., a choke) separating the interior chamber into two volumes and forcing fluid flow through the pressure drop device. The effective fluid passage provided by the pressure drop device is smaller than the fluid passage for one or both of the inlet to and/or the outlet from the interior chamber. Fluid entering the pulsation control device reacts with fluid contained within the volume thereof on both sides of the baffle. The baffle attenuates pressure pulses within fluid passing through the interior chamber in response to operation of the reciprocating pump. The pressure drop device dampens high frequency pulsation magnitudes of pressure pulses within fluid passing through the interior chamber in response to operation of the reciprocating pump.

Provided is a linear compressor. Provided is a linear compressor. The linear compressor includes a shell defining an internal space, a compressor body disposed in the internal space, and a passage guide disposed between the shell and the compressor body. The passage guide may include a first guide part extending along an inner surface of the shell in an axial direction and a second guide part extending from the first guide part to the compressor body in a radial direction.

In a permanent magnet embedded electric motor, a rotor iron core of a rotor disposed on an inner diameter side of a stator includes: a plurality of first slits that are formed on a radial direction outer side of a magnet insertion hole, and communicate with the magnet insertion hole; a plurality of second slits formed at positions opposed to and spaced apart from the first slits; inter-slit iron core portions formed between the first slits and the second slits; outer side iron core portions formed between the second slits and an outer circumferential surface of the rotor iron core; space portions communicating with rotating direction end portions of the magnet insertion hole; and thin iron core portions that are formed between the space portions and the outer circumferential surface of the rotor iron core, and extend in a rotating direction.