A compressor having a rotor assembly within which a rotor is rotated on an eccentric shaft in a sealed chamber. Two or more intake ports are provided that open into the sealed chamber and two or more exhaust ports are provided with one way valves, to permit compressed gas to exit the sealed chamber. The geometry of the rotor and sealed chamber and eccentric drive are such that apices of the rotor remain in contact with a peripheral wall of the sealed chamber as the rotor rotates and apex seals are provided on the apices of the rotor to prevent leakage of the gas around the apices of the rotor. In a preferred embodiment the rotor is a multi-lobed rotor orbiting within a trochoidal chamber.

A compressor having a rotor assembly within which a rotor is rotated on an eccentric shaft in a sealed chamber. Two or more intake ports are provided that open into the sealed chamber and two or more exhaust ports are provided with one way valves, to permit compressed gas to exit the sealed chamber. The geometry of the rotor and sealed chamber and eccentric drive are such that apices of the rotor remain in contact with a peripheral wall of the sealed chamber as the rotor rotates and apex seals are provided on the apices of the rotor to prevent leakage of the gas around the apices of the rotor. In a preferred embodiment the rotor is a multi-lobed rotor orbiting within a trochoidal chamber.

An epitrochoidal vacuum pump includes a housing having a chamber, a rotor rotatably received within the internal space of the chamber, and a drive shaft configured to rotate the rotor eccentrically about an axis within the chamber in an epitrochoidal manner. An externally toothed guide sprocket meshes with and guides movement of a guide gear of the rotor as it is driven by the drive shaft. A chamber inlet draws air under negative pressure into the housing, and an outlet is provided to expulse air under positive pressure from the housing. Further, a fluid inlet is provided to input lubricant along the drive shaft and into the internal space of the chamber. The fluid inlet is communicated by channel(s) in an interior of the housing. The lubricant is drawn into the housing via a pressure differential.

An epitrochoidal vacuum pump includes a housing having a chamber, a rotor rotatably received within the internal space of the chamber, and a drive shaft configured to rotate the rotor eccentrically about an axis within the chamber in an epitrochoidal manner. An externally toothed guide sprocket meshes with and guides movement of a guide gear of the rotor as it is driven by the drive shaft. A chamber inlet draws air under negative pressure into the housing, and an outlet is provided to expulse air under positive pressure from the housing. Further, a fluid inlet is provided to input lubricant along the drive shaft and into the internal space of the chamber. The fluid inlet is communicated by channel(s) in an interior of the housing. The lubricant is drawn into the housing via a pressure differential.

A rotary compressor is provided that may include a casing, a cylinder, a main bearing, a sub bearing, a rotational shaft, a roller, and at least one vane. The cylinder may include at least one elastic deformation unit to absorb impact with the at least one vane. With this structure, a collision force caused due to chattering of the at least one vane may be absorbed to suppress or prevent friction loss and/or wear between the cylinder and the vane, thereby enhancing compressor efficiency, reducing vibration noise, and enabling fast initial actuation.

A rotary compressor is provided that may include a casing, a cylinder, a main bearing, a sub bearing, a rotational shaft, a roller, and at least one vane. The cylinder may include at least one elastic deformation unit to absorb impact with the at least one vane. With this structure, a collision force caused due to chattering of the at least one vane may be absorbed to suppress or prevent friction loss and/or wear between the cylinder and the vane, thereby enhancing compressor efficiency, reducing vibration noise, and enabling fast initial actuation.

Pressure changing devices and methods of making and using the same are disclosed. One pressure changing device includes an elliptic cylinder and a piston that has an external surface with a trochoid cross-section. Another pressure changing device includes a piston and a rotating cylinder that has an internal surface with a trochoid cross-section. Another pressure changing device includes two fixed axes, one for rotation of one component and another for orbiting or oscillation of the other component. The devices and methods include stacked pressure changing devices with one or more common shafts. The pressure changing device may be easier and less expensive to manufacture and repair than prior pressure changing devices of the same or similar functionality, and can provide efficient gap sealing in a high pressure expansion part of a compression or expansion cycle.

Pressure changing devices and methods of making and using the same are disclosed. One pressure changing device includes an elliptic cylinder and a piston that has an external surface with a trochoid cross-section. Another pressure changing device includes a piston and a rotating cylinder that has an internal surface with a trochoid cross-section. Another pressure changing device includes two fixed axes, one for rotation of one component and another for orbiting or oscillation of the other component. The devices and methods include stacked pressure changing devices with one or more common shafts. The pressure changing device may be easier and less expensive to manufacture and repair than prior pressure changing devices of the same or similar functionality, and can provide efficient gap sealing in a high pressure expansion part of a compression or expansion cycle.

A rotary piston compressor for compressing gas, in particular carbon dioxide, in which a side wall face of a housing side wall and a respective planar sealing face of a respective housing cover enclose a working chamber and a rotary piston is rotatably mounted in the working chamber on an eccentric. A respective planar-seal receiving channel is formed in the piston bases of the rotary piston and a planar seal is arranged in each of the planar-seal receiving channels. To press the seal surface of the respective planar seal against the respective planar sealing face, lateral-surface openings in the piston lateral surface of the rotary piston have a pressure-transmitting connection to the respective planar-seal receiving channel via pressure leadthrough lines, formed inside the rotary piston and each open into the respective planar-seal receiving channel on a side of the respective planar seal facing away from the seal surface.

A rotary piston compressor for compressing gas, in particular carbon dioxide, in which a side wall face of a housing side wall and a respective planar sealing face of a respective housing cover enclose a working chamber and a rotary piston is rotatably mounted in the working chamber on an eccentric. A respective planar-seal receiving channel is formed in the piston bases of the rotary piston and a planar seal is arranged in each of the planar-seal receiving channels. To press the seal surface of the respective planar seal against the respective planar sealing face, lateral-surface openings in the piston lateral surface of the rotary piston have a pressure-transmitting connection to the respective planar-seal receiving channel via pressure leadthrough lines, formed inside the rotary piston and each open into the respective planar-seal receiving channel on a side of the respective planar seal facing away from the seal surface.