A rotary piston and cylinder device (1) comprising a rotor (2), a stator (4) and a rotatable shutter (3), the rotor comprising a piston (5) which extends from the rotor into a working chamber, the rotor and the stator together defining a working chamber, the shutter arranged to extend through the working chamber and forming a partition therein, and the shutter comprising a slot which allows passage of the piston therethrough, a bearing (20) which mounts the rotor relative to the stator, the rotor comprising a formation (12; 30) which extends substantially axially away from the chamber, and the formation being radially outward of the bearing and extending around the axis of rotation, and the formation comprising a surface which at least in part defines a space between the rotor and the stator, and at least part of that space and/or the formation overlaps in an axial direction with the bearing.

A scroll device includes a fixed scroll with an idler shaft bearing, an orbiting scroll with another idler shaft bearing; and an eccentric idler shaft having first and second arms extending in opposite directions and ending at first and second ends, the first and second arms supported by the fixed scroll idler shaft bearing and the orbiting scroll idler shaft bearing, respectively. The eccentric idler shaft has a hollow core extending from the first end to the second end, with at least one channel extending through the first arm and enabling fluid communication between the hollow core and the at least one first bearing, and at least one second channel extending through the second arm and enabling fluid communication between the hollow core and the least one second bearing.

A housing of a scroll type expansion machine includes: a suction port formed at a position on the opposite side to a drive shaft with a fixed scroll interposed therebetween; a discharge port formed on the side of a drive-side bearing closer to the tip end of the drive shaft; a low pressure chamber formed on the outer side of an orbiting-side scroll portion when viewed from the axial direction of the drive shaft; and a tip end-side low-pressure space being a space in which a sealing member is disposed, and has: a partition wall partitioning the tip end-side low-pressure space and the low-pressure chamber from each other; and a communication space communicating the tip end-side low-pressure space with the low-pressure chamber.

An expander system for recovering waste heat, a waste heat recovery system including such an expander system, a vehicle including such a waste heat recovery system and a method for manufacturing such an expander system. The expander system includes a shaft and a coupling portion including a first sealing unit and a second sealing unit. The shaft is inserted through the coupling portion to an expanding unit. The first sealing unit and the second sealing unit are arranged facing one another along the shaft. The first sealing unit and the second sealing unit are configured to seal the shaft in an axial direction relative to the shaft.

A gas processing system includes a vessel defining a cavity for processing a gas. The vessel includes a process gas inlet for accepting process gas at an input pressure, and a process gas outlet for discharging process gas at an output pressure. The gas processing system further includes a shaft coupled to the vessel and a multistage sealing system comprising multiple seals spaced along the shaft. The shaft is configured to transfer mechanical energy to or from gas in the vessel. Each adjacent pair of seals defines a corresponding pressure space therebetween. One of the pressure spaces is an equalizing pressure space in hydraulic communication with the process gas inlet via a flow line, such that in operation, pressure in the equalizing pressure space is maintained at an equalized pressure with respect to a pressure in the process gas inlet.

An expander system for recovering waste heat, a waste heat recovery system including such an expander system, a vehicle including such a waste heat recovery system and a method for manufacturing such an expander system. The expander system includes a shaft and a coupling portion including a first sealing unit and a second sealing unit. The shaft is inserted through the coupling portion to an expanding unit. The first sealing unit and the second sealing unit are arranged facing one another along the shaft. The first sealing unit and the second sealing unit are configured to seal the shaft in an axial direction relative to the shaft.

A housing of a scroll type expansion machine includes: a suction port formed at a position on the opposite side to a drive shaft with a fixed scroll interposed therebetween; a discharge port formed on the side of a drive-side bearing closer to the tip end of the drive shaft; a low pressure chamber formed on the outer side of an orbiting-side scroll portion when viewed from the axial direction of the drive shaft; and a tip end-side low-pressure space being a space in which a sealing member is disposed, and has: a partition wall partitioning the tip end-side low-pressure space and the low-pressure chamber from each other; and a communication space communicating the tip end-side low-pressure space with the low-pressure chamber.

A motor shaft seal assembly configured to prevent external elements from entering internal portions of a motor housing of a motor through a motor shaft seal is provided. The motor shaft seal assembly includes a seal plate configured to mount to a motor. The seal plate has a seal aperture configured to encircle a motor shaft of the motor. An inlet port is mounted to the seal plate. An internal passage extends from the inlet port, through the seal plate, to a plurality of annular cavities positioned proximate the motor shaft. A supply of a flexible sealing compound is provided to the plurality of annular cavities in a manner such as to contact the motor shaft, thereby forming an additional barrier to prevent external elements from entering internal portions of the motor through the motor shaft seal.

A seal assembly configured for use with a high pressure single screw compressor includes a seal body and at least one attachment structure. The at least one attachment structure fixedly attaches the seal body to the rotor of the compressor, such that the seal body is rotatable along with the rotor. The seal body has a textured outer surface which creates a labyrinthine path between the compressor housing and the seal body.

A rotary piston and cylinder device (1) comprising a rotor (2), a stator and a shutter disc (3), the rotor comprising a piston (5) which extends from the rotor into the cylinder space, the rotor and the stator together defining the cylinder space, the shutter disc passing through the cylinder space and forming a partition therein, and the disc comprising a slot (3a) which allows passage of the piston therethrough, and a surface of the rotor and a surface of the stator opposing each other forming a close-running surface pair, and at least one of the surfaces comprising an abradable coating (10) which is provided with a plurality of recess formations, and the recess formations are discontinuous from each other.