A hydraulic device for an internal combustion engine or a gearing system, the hydraulic device including a housing featuring a chamber wall structure which delineates a pressure chamber for a pressurised hydraulic fluid; an actuating member which can be adjusted in the housing relative to the chamber wall structure in an actuating direction and in an actuating counter direction opposite to the actuating direction in order to adjust the delivery volume or phase position; and a sealing element including a sealing structure and a spring structure which is supported or moulded on one of the chamber wall structure and the actuating member, preferably the actuating member, and presses the sealing structure into sealing contact with the other of the chamber wall structure and the actuating member with a spring force in order to seal off the pressure chamber. The sealing structure and the spring structure are moulded in one piece.

An oil seal member is provided at an outside surface of a member performing whirling motion such as a rotary engine rotor. A sliding face of the oil seal member that slides relatively to a stationary-side member is provided with a step extending circumferentially, and has a relatively high surface formed on one radial side with respect to the step and a relatively low surface on the other radial side. The high surface is provided with pumping grooves to pump oil tending to leak from the high surface side into the low surface side, into the high surface side by sliding relatively to the stationary-side member.

An oil seal member is provided at an outside surface of a member performing whirling motion such as a rotary engine rotor. A sliding face of the oil seal member that slides relatively to a stationary-side member is provided with a step extending circumferentially, and has a relatively high surface formed on one radial side with respect to the step and a relatively low surface on the other radial side. The high surface is provided with pumping grooves to pump oil tending to leak from the high surface side into the low surface side, into the high surface side by sliding relatively to the stationary-side member.

Disclosed herein is a rotary engine a supply flow passage provided in the housing to allow the lubricating oil to move therethrough, a sealing part arranged to contact the rotor to selectively close the supply flow passage, and an elastic part configured to press the sealing part toward the combustion chamber.

Disclosed herein is a rotary engine a supply flow passage provided in the housing to allow the lubricating oil to move therethrough, a sealing part arranged to contact the rotor to selectively close the supply flow passage, and an elastic part configured to press the sealing part toward the combustion chamber.

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.

A rotary engine casing having at least one end wall of an internal cavity for a rotor including a seal-engaging plate sealingly engaging the peripheral wall to partially seal the internal cavity and a member mounted adjacent the seal-engaging plate outside of the internal cavity. The member and seal-engaging plate having abutting mating surfaces which cooperate to define between them at least one fluid cavity communicating with a source of liquid coolant. When the casing includes a plurality of rotor housings, the end wall may be between rotor housings. A method of manufacturing a rotary engine casing is also discussed.

A rotary engine casing having at least one end wall of an internal cavity for a rotor including a seal-engaging plate sealingly engaging the peripheral wall to partially seal the internal cavity and a member mounted adjacent the seal-engaging plate outside of the internal cavity. The member and seal-engaging plate having abutting mating surfaces which cooperate to define between them at least one fluid cavity communicating with a source of liquid coolant. When the casing includes a plurality of rotor housings, the end wall may be between rotor housings. A method of manufacturing a rotary engine casing is also discussed.

A rotary piston compressor is disclosed, comprising a housing having an epitrochoidal shaped inner bore, peripheral inlet and exhaust ports located in the bore, and a rotary piston rotatably mounted within the housing. The central portion of each rotary piston flank is configured such that, at the closest point between the flank central portion and the housing between the exhaust port of the trailing compression cycle and the inlet port of the leading compression cycle, the radial spacing between the rotary piston flank and the housing is maintained such that the volumes enclosed by the rotary piston on either side of the closest point in the respective trailing and leading compression cycles are substantially sealed from one another. The end portions of each rotary piston flank are configured such that radial spacing between the rotary piston flank and the housing exceeds that between the central portion and the housing.

A method and system is provided for pressure balancing one or more seals in machines such as expanders and/or compressors using the process fluid which is being expanded or compressed to provide the pressure for pressure balancing the other side of the one or more seals. The one or more seals may be part of a pressure containing chamber which may comprise a seal, a bearing and/or a gear on a rotating shaft common to the seal. An amount of pressure to be supplied to housing(s) for a machine so as to create a pressure cascade, and thereby dropping the pressure in each subsequent chamber as pressure approaches atmosphere. Pressure differentials may be directed to leak process fluid to the chamber into the process. Pressurized lube oil systems may be employed for balancing pressure and delivering lubricant to the seals, bearings and gears.