A method and apparatus to reduce the intrusion of ambient air into an open-crankcase compressor. The method employs recycle control to reduce the magnitude of vacuum inside the compressor relative to ambient air pressure, and thereby eliminate the intrusion of said ambient air into said compressor.

Methods and systems for applying charge to a piezoelectric element include and/or facilitate implementation of processes including cyclical multi-stage processes for: providing a piezoelectric element with an accumulated charge; providing one or more charge holding elements with a scavenged charge from the piezoelectric element; substantially removing or discharging a remaining charge from the piezoelectric element; and applying the scavenged charge to the piezoelectric element with an opposite polarity in relation to the polarity of the remaining charge.

A method of compressing gas includes maintaining a volume of gas at a first pressure within a first chamber. Pressurized liquid is forced into the first chamber through a nozzle having a curved profile. Based on the Coanda effect, the liquid compresses the volume of gas to a second pressure greater than the first pressure. The liquid is separated from the gas in a second chamber while maintaining the gas at the second pressure to provide compressed, dry gas.

A variable displacement swash compressor includes a housing, a drive shaft, a swash plate, a link mechanism, pistons, a conversion mechanism, an actuator, and a control mechanism. The housing includes a suction chamber, a discharge chamber, a swash plate chamber, and cylinder bores. The control mechanism controls the actuator. The actuator includes a partitioning body, a movable body, and a control pressure chamber. At least one of the suction chamber and the swash plate chamber is a low pressure chamber. The control mechanism includes a control passage, which connects the control pressure chamber, the low pressure chamber, and the discharge chamber, and a control valve, which adjusts the open degree of the control passage. The control passage is partially formed in the drive shaft. The movable body increases the inclination angle of the swash plate when the pressure of the control pressure chamber increases.

An air compressor of weight-reduction type is disclosed, wherein the bearing and the main housing thereof are formed integrally, so that when the piston body conducts reciprocating motion within the cylinder at high frequencies, the bearing is firmly fixed on the main housing without nonfunctioning or falling off. Furthermore, the main housing and the cylinder thereof are made of plastic and formed integrally. The main housing is formed with a wind collecting hood to facilitate the air flow being introduced through the main housing for rapidly dissipating the heat generated by the bearing and the heat generated from the reciprocating motion of the piston body. Accordingly, the manufacturing cost of the air compressor can be reduced to achieve an economical design, and the weight of the air compressor can be reduced to facilitate the compressor being carried onto a vehicle.

An oil-free screw compressor includes: a casing having a rotor chamber; a bearing supporting rotary shafts of the screw rotors; a shaft seal device including an oil seal portion and an air seal portion; an atmosphere open hole formed in the shaft seal device; at least one communication hole formed in the rotary shaft; and an annular space communicating the atmosphere open hole with the at least one communication hole communicate with each other. The annular space includes an inner peripheral annular space formed on an inner peripheral side of the casing. Assuming an open cross-sectional area of the inner peripheral annular space as S1, a total open cross-sectional area of the communication holes as S2, an open cross-sectional area of the i-th communication hole out of the communication holes as S2i, and the number of communication holes as n (n being a natural number of 1 or more), a following relationship is satisfied.

[00001]$S.Math..Math.1\geqq S.Math..Math.2=\underset{i=1}{\overset{n}{.Math.}}.Math..Math.S.Math..Math.2.Math.i$

A hermetic compressor accommodates in hermetic container (101) electric motor element (102) and compression element (103) driven by electric motor element (102). Compression element (103) includes crankshaft (110) including main shaft (115), eccentric shaft (114), and flange (116), cylinder block (111) having cylinder bore (123) passing through cylinder block (111) in a cylindrical shape, and piston (112) configured to reciprocate in cylinder bore (123). Compression element (103) also includes connecting rod (113) connecting piston (112) and eccentric shaft (114) and bearing (124) formed on cylinder block (111) for pivotally supporting a radial load that acts on main shaft (115) of crankshaft (110). Crankshaft (110) further includes communicating oil supply passage (118) provided in flange (116), main shaft oil supply passage (119) configured for communication between communicating oil supply passage (118) and cylindrical surface (115a) of main shaft (115), and eccentric shaft oil supply passage (120) configured for communication between communicating oil supply passage (118) and cylindrical surface (114a) of eccentric shaft (114).

A hermetic compressor is provided. The hermetic compressor may include a compressor body spaced apart from an inner surface of a shell and including a motor unit and a compression unit; at least one support spring provided between the shell and the compressor body and that elastically supports the compressor body with respect to the shell; at least one stopper cap fixed to the inner surface of the shell or the compressor body facing the inner surface of the shell; and a stopper bar that extends from the compressor body or the inner surface of the shell and inserted into the at least one stopper cap with a predetermined distance therebetween. By mechanically restraining vibration of the compressor body and limiting amplitude of the compressor body, vibration noise of the compressor body may be reduced and the compressor body may be suppressed from being in contact with the shell to thereby prevent damage to the compressor body.

A switch (10, 200) is provided for installation in the air conditioning (A/C) system (12) in a vehicle (16) for intermittently operating the clutch (20) in the A/C system (12) each time the control (44) in the A/C system (12) provides power to operate the clutch (20) to prevent slugging. This turns the compressor (14) a few turns each time the clutch (20) is energized during intermittent operation to purge liquid refrigerant and lubricant from the compressor (14) to prevent slugging. The switch (10, 200) can be installed in existing vehicles by connecting the switch (10, 200) in the wiring harness (18) of the A/C system (12) to the power lead (38) from the control (44) to the clutch (20) and between the ground lead (40) from the clutch (20) and a ground. The switch (10, 200) can include a microcontroller (52) for controlling the operation of a power transistor (70) to intermittently ground the clutch to provide the intermittent operation. A battery (202) can be provided to power the microcontroller (52) for a set period of time after an initial intermittent operation. This prevents additional intermittent operation for the set period of time.

A switch (10, 200) is provided for installation in the air conditioning (A/C) system (12) in a vehicle (16) for intermittently operating the clutch (20) in the A/C system (12) each time the control (44) in the A/C system (12) provides power to operate the clutch (20) to prevent slugging. This turns the compressor (14) a few turns each time the clutch (20) is energized during intermittent operation to purge liquid refrigerant and lubricant from the compressor (14) to prevent slugging. The switch (10, 200) can be installed in existing vehicles by connecting the switch (10, 200) in the wiring harness (18) of the A/C system (12) to the power lead (38) from the control (44) to the clutch (20) and between the ground lead (40) from the clutch (20) and a ground. The switch (10, 200) can include a microcontroller (52) for controlling the operation of a power transistor (70) to intermittently ground the clutch to provide the intermittent operation. A battery (202) can be provided to power the microcontroller (52) for a set period of time after an initial intermittent operation. This prevents additional intermittent operation for the set period of time.