A display structure of a pressure gauge of an air compressor, the air compressor is received in an accommodation box, and a scale portion of the pressure gauge is viewable via a displaying opening of the accommodation box, the pressure gauge includes a cylindrical body which is transparent and is formed in a pen shape, and the pressure gauge includes a colored O-ring configured to indicate a pressure value of the scale portion. The scale portion is not printed on the cylindrical body of the pressure gauge and includes a transparent panel on which the pressure value of the scale portion is marked on an internal face of the transparent panel, and the internal face faces the cylindrical body of the pressure gauge.

Microfluidic pumps are provided that use electrowetting to manipulate the location of one or more droplets of a working fluid (e.g., water) in order to pump tears, blood, laboratory samples, carrier fluid, or some other payload fluid. The working fluid is separated from the payload fluid by one or more droplets of an isolating fluid that is immiscible with the working fluid. The working fluid is manipulated via electrowetting, by applying voltages to two or more electrodes, to repeatedly move back and forth. Forces, pressures, and/or fluid flows exerted by the working fluid are coupled to the payload fluid via the droplet(s) of isolation fluid and reed valves, diffuser nozzles, or other varieties of valve can act as flow-rectifying elements to convert the coupled forces into a net flow of the payload fluid through the pump.

A hermetic compressor includes a compressor shell, a terminal provided on the compressor shell, a terminal guard erected on the compressor shell and surrounding the terminal, and a terminal cover mounted to the terminal guard and covering the terminal. A terminal chamber is defined by the compressor shell, the terminal guard, and the terminal cover. Except for at least a body of the terminal, metal portions facing the terminal chamber are generally covered with an insulator such that the metal portions are not exposed to the terminal chamber. The insulator includes an insulating portion that covers an inner surface of the terminal guard.

Systems and methods to enhance the flow of fracturing fluid into a wellhead during a high-pressure fracturing operation may include providing a pump frame and a crankshaft. A plurality of first plungers may be connected to the crankshaft and may reciprocate in a first plane. The hydraulic fracturing pump also may include a plurality of second plungers connected to the crankshaft and positioned to reciprocate in a second plane. The first plane and the second plane may define a non-zero offset angle between the first plane and the second plane. The crankshaft may include a plurality of crankpins, and each of the crankpins may be connected to one of the first plungers and one of the second plungers. The first plungers may pump a first fracturing fluid and the second plungers may pump a second fracturing fluid different from the first fracturing fluid.

A variable-pressure air pump includes a first cylinder with a first chamber and a second cylinder with a second chamber movably connected with one another. The second chamber fluidly communicable with the outside of the variable-pressure air pump selectively. A discharge device includes a connecting member and a switch movably connected with one another. The connecting member defines at least one discharge hole fluidly connecting with the second chamber. The switch has at least one flow guide portion and at least one blocking portion. The switch is movable between a first position in which the at least one flow guide portion is adjacent and opens to the at least one discharge hole and a second position in which the at least one blocking portion is adjacent to and blocks the at least one discharge hole.

Disclosed are a magnetic bearing, a compressor and an air conditioner. The magnetic bearing includes a radial stator, where the radial stator has a plurality of stator teeth extending inwardly in a radial direction thereof; two axial stators are arranged on two axial sides of the stator teeth, respectively; and radial control coils are wound on the stator teeth, the radial control coil being located outside an area of the stator teeth covered oppositely by the two axial stators. The magnetic bearing, the compressor and the air conditioner can effectively reduce the degree of coupling between a radial electromagnetic control magnetic circuit and an axial electromagnetic control magnetic circuit, and reduce the control difficulty of the magnetic bearing.

In a linear motor and the linear compressor having the same according to the present disclosure, a plurality of magnets are coupled to a stator equipped with a winding coil, and a mover core made of magnetic material instead of a permanent magnet is provided on the mover, and by the magnetizing plurality of magnets in the same direction, the motor output can increase by increasing thrust instead of decreasing the centering force for the mover core. In addition, as it is applied to a two-pore motor, it is possible to easily control the mover core and to easily perform an assembly operation and a magnetization operation for the magnet. In addition, as the stator is made of a grain-oriented core, core loss may be reduced and the motor efficiency may be improved.

The objective of the present invention is to provide a compressor with which it is possible to simplify the manufacture of a soundproof cover. A compressor (1) is provided in an air conditioning device for an automobile. The compressor (1) is provided with: a main body portion which has a discharge port (12) and which compresses a refrigerant; and a soundproof cover (20) which includes a first cover (30) and a second cover (40), separate from the first cover (30), and inside which an internal space is formed, the main body portion being accommodated in the internal space. The soundproof cover (20) includes, in a part in which the first cover (30) and the second cover (40) face one another: a contacting portion (24) in which the first cover (30) and the second cover (40) are in contact with one another, thereby separating the internal space and an external space outside the soundproof cover (20); and a spaced-apart portion (25) in which the first cover (30) and the second cover (40) are separated from one another to form a first opening (26) connecting the internal space and the external space. The discharge port (12) is inserted through the first opening (26).

A fluid pump for pumping a fluid. One or more piston-cylinder arrangements each include a respective cylinder portion, a respective head portion and a respective piston portion together defining a respective pumping chamber. One or more connecting arrangements connect a crank member to the one or more piston-cylinder arrangements to drive the respective piston portion of each of the one or more piston-cylinder arrangements. A housing and the respective piston portion of each of the one or more piston-cylinder arrangements together house the crank member in an interior. The interior is sealed to capture blow-by. A transmission is arranged to transmit power, for rotating the crank member, into the housing magnetically, electrically or both.

A sealed refrigerant compressor (10A) accommodates an electric component (20A) and a compression component (30) in a sealed container (11). A crankshaft (40) included in the compression component (30) includes a main shaft part (41) and an eccentric shaft part (42). A main shaft part (41) is secured to a rotor (22A) of the electric component (20A). The rotor (22A) is provided with a balance adjustment means such as a balance hole (27), which adjusts an unbalanced load caused by the structure of the main shaft part (41).