The invention relates to a pump unit that can be driven by an electric motor, in particular for providing vacuum for a pneumatic brake booster, including a pump housing that can be closed by a working-chamber cover and at least one elastic displacement element, wherein a working chamber is bounded between the displacement element and the working-chamber cover and wherein inlet valves and outlet valves and inlet channels and outlet channels associated with the valves are associated with the working chamber. According to the invention, in order to reduce noise emissions, devices for reducing a contact surface between the working-chamber cover and the pump housing are provided.

A fluid system includes a pumping flowline, wherein the pumping flowline is in selectable fluid communication with a production flowline, a cylinder including a first port and a second port, a piston slidably disposed in the cylinder, the piston sealing against an inner surface of the cylinder to form a first chamber and a second chamber, wherein the first chamber is in fluid communication with the first port and the second chamber is in fluid communication with the second port, and a first flowline in fluid communication with the first port of the cylinder and the pumping flowline, the first flowline including a first flowline valve, wherein, in response to opening the first flowline valve, the piston is displaced through the cylinder in a first direction to expand a volume of the first chamber of the cylinder.

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.

An improved air compressor generally includes a cylinder fitted with a piston body, a main frame for mounting a motor, and an air storage container. The cylinder defines at its top wall a plurality of exit holes, which are separated by a plurality of blocking walls and regulated by a control mechanism. When the compressed air is produced in the cylinder causing the control mechanism to open the exit holes, the instantaneous high-pressure air that flows through the exit holes can be restrained by the blocking walls to prevent the air from interfering with operation of the control mechanism, so that the piston body can conduct reciprocating motion more smoothly and thus the performance of the air compressor can be increased.

Provided is a muffler for an air-conditioning apparatus, which is compact and has a small pressure loss, and an air-conditioning apparatus including the same. The muffler for an air-conditioning apparatus including a muffler main body which has small diameter portions on an inlet side and an outlet side, the small diameter portions having inner diameters smaller than an inner diameter of a central portion of the muffler main body, an inlet pipe connected to the small diameter portion on the inlet side of the muffler main body; and an outlet pipe connected to the small diameter portion on the outlet side of the muffler main body. The inlet pipe is inserted into the muffler main body, and has a distal end positioned at a center of a length from an inlet to an outlet of the muffler main body. The distal end side of the inlet pipe inserted into the muffler main body has an inner diameter smaller than an inner diameter of the inlet pipe on an upstream of the distal end side.

A shunt pulsation trap for a positive-displacement gas-transfer machine having a gas transfer chamber with an intake port and a discharge port and having at least one positive-displacement drive device (such as two cooperating rotors) defining a compression region of the transfer chamber. The trap includes a pulsation-trap chamber arranged for parallel fluid flow with the machine transfer chamber. The trap has a first (e.g., inlet) port in communication with the compression region of the transfer chamber (e.g., at least one lobe span away or totally isolated from the transfer-chamber intake port), a second (e.g., discharge) port in communication with the discharge port of the transfer chamber, and at least one pulsation dampener in the pulsation-trap chamber. In this way, the shunt pulsation trap traps and attenuates gas pulsations before discharge from the machinery transfer chamber, thereby reducing induced NVH and improving machinery efficiency.

A linear compressor is provided that may include a shell; a compressor body accommodated in the shell to compress a refrigerant; a discharge cover assembly through which the refrigerant compressed in the compressor body may be discharged; a cover pipe that extends from the discharge cover assembly to discharge the refrigerant discharged into the discharge cover assembly to an outside of the discharge cover assembly; a discharge pipe coupled to the shell to discharge the refrigerant flowing along the cover pipe to an outside of the shell; a loop pipe having a first end connected to the cover pipe and a second end connected to the discharge pipe; and a coupling member that respectively couples both the first and second ends of the loop pipe to the cover pipe and the discharge pipe. The coupling member may include a connection member, a first portion of which is inserted into the loop pipe and a second portion of which is inserted into the discharge pipe or the cover pipe. The connection member may be formed of a steel material. At least one of the discharge pipe or the cover pipe may be formed of a steel material.

A linear compressor is provided. The linear compressor may include a discharge cover including a plurality of covers stacked in an axial direction.

A linear compressor is provided that may include a cylinder which defines a compression space for a refrigerant and into which a piston that reciprocates in an axial direction may be inserted, a frame in which the cylinder may be accommodated, a discharge valve that selectively discharges the refrigerant compressed in the compression space for the refrigerant, a spring assembly coupled to the discharge valve, a discharge cover on which the spring assembly may be seated and having a discharge space through which the refrigerant discharged through the discharge valve may flow, and a first gasket seated inside of the discharge cover to support the spring assembly and attenuate vibration during an operation of the discharge valve.