A compressor includes a shell, a first scroll member, a second scroll member and a sealing assembly. The shell defines a first pressure region and a second pressure region. The first scroll member is disposed within the shell and includes a first end plate and a first scroll wrap. The second scroll member includes a second end plate and a second scroll wrap. The second scroll wrap meshingly engages the first scroll wrap to define a compression chamber therebetween. The seal assembly fluidly separates the first and second pressure regions from each other. The seal assembly includes a first plate, a second plate, a first sealing member and a second sealing member. The first sealing member is sealingly engaged with the first plate and the second plate. The second sealing member is sealingly engaged with the first sealing member and the first plate.

A scroll pump includes a first scroll member having a first involute, a second scroll member scroll member having a second involute, and a camshaft rotatably connected to the first scroll member and to the second scroll member. A link is pivotably connected to the first scroll member and the second scroll member. The first and second scroll members cooperate to define a working volume wherein a working fluid is pressurized during operation of the scroll pump. The second scroll member is configured to equalize pressure across first and second opposed surfaces of an end plate thereof. The second scroll member includes a piston and cavity configured to bias the second scroll member toward the first scroll member in response to pressure across the first and second opposed surfaces of the end plate of the second scroll member.

A compressor includes a shell, a first scroll member, a second scroll member and a sealing assembly. The shell defines a first pressure region and a second pressure region. The first scroll member is disposed within the shell and includes a first end plate and a first scroll wrap. The second scroll member includes a second end plate and a second scroll wrap. The second scroll wrap meshingly engages the first scroll wrap to define a compression chamber therebetween. The seal assembly fluidly separates the first and second pressure regions from each other. The seal assembly includes a first plate, a second plate, a sealing member. The sealing member is sealingly engaged with the first plate and the second plate.

One of a pair of a fixed scroll and an orbiting scroll is the scroll including a step portion provided only at a predetermined position along a spiral direction on a blade bottom surface of a spiral wrap, and the other one of the scrolls is the scroll including a step portion provided only at a predetermined position along a spiral direction on a blade tip surface of a spiral wrap. A blade bottom surface of an end plate of the fixed scroll is set as a reference surface for setting a chip gap between both the scrolls. When a wrap height of the spiral wrap of the orbiting scroll is represented by (L) (Lo, Li) and a wrap height of the spiral wrap of the fixed scroll is represented by (lo, li), L (Lo, Li)>1 (lo, li) is satisfied.

A rotor for a rotary internal combustion engine with a first face seal biased axially outwardly away from the first end face has opposed curled ends abutting a first end seal of a respective one of the adjacent apex portions, and a second face seal biased axially outwardly away from the second end face has opposed curled ends abutting a second end seal of a respective one of the adjacent apex portions. A rotary internal combustion engine and a method of sealing chambers of a Wankel engine are also discussed.

A rotor for a rotary internal combustion engine with a first face seal biased axially outwardly away from the first end face has opposed curled ends abutting a first end seal of a respective one of the adjacent apex portions, and a second face seal biased axially outwardly away from the second end face has opposed curled ends abutting a second end seal of a respective one of the adjacent apex portions. A rotary internal combustion engine and a method of sealing chambers of a Wankel engine are also discussed.

A positive displacement pump assembly includes a rotor housing defining a rotor cavity, and an end plate configured to at least partially close one end of the rotor cavity. Rotors are supported on and fixed to rotor shafts and extend through the rotor cavity. A first pair of bearings fixing the rotor shafts to the end plate. A second pair of bearings fixes the rotor shafts to the rotor housing, preventing relative axial movement between the rotor shafts and the rotor housing. The end plate is axially movable with the rotor shafts when the rotor shafts vary in axial length due to thermal fluctuations so that changes in an axial clearance at end faces of the rotors are reduced.

Durability of a vacuum pump is prevented from degrading by suppressing abrasion of a rotor and a side plate. The vacuum pump has a hollow cylinder chamber S having an opening at an end portion of a casing body, a rotor which is rotationally driven in the cylinder chamber S, a side plate for blocking the opening of the cylinder chamber S, and a pump cover which is disposed at the opposite side to the rotor so as to sandwich the side plate between the pump cover and the rotor, and the side plate is provided with an intercommunication port which confronts a shaft hole of the rotor and intercommunicates with a space between the side plate and the pump cover.

A sealing arrangement between a rotating plane surface on a rotor and a machine housing prevents flow of process fluid between an internal volume and an external volume of the machine housing. The sealing arrangement includes a piston arrangement, and a sealing bearing ring between the piston arrangement and the rotating plane surface. A fluid supply line supplies pressurized lubrication fluid through the machine housing to a piston cavity, wherein the piston arrangement further includes piston fluid channels and the bearing sealing ring includes lubrication conduits through the bearing sealing ring, corresponding with the piston fluid channels. The pressurized lubrication fluid is arranged for moving the piston arrangement against the sealing bearing ring and thus moving the sealing bearing ring against the sealing surface thus forming a sealing arrangement.

Disclosed are a sealing structure and a scroll air compressor having the same. The sealing structure includes: an orbiting scroll including an orbiting scroll spiral tooth (11), the orbiting scroll spiral tooth (11) being provided with an orbiting scroll spiral tooth groove (12), an orbiting scroll wear-resistant sealing strip (30) being provided in the orbiting scroll spiral tooth groove (12); a stationary scroll including a stationary scroll spiral tooth (21) matched with the orbiting scroll spiral tooth (11), the stationary scroll spiral tooth (21) being provided with a stationary scroll spiral tooth groove (22), a stationary scroll wear-resistant sealing strip (40) is provided in the stationary scroll spiral tooth groove (22), the wear-resistant sealing strip (30) is divided into sections including a high-temperature and high-pressure section (30a) and a medium-temperature and medium-pressure section (30b). The sealing structure reduces costs of use and maintenance of the sealing strip; a buffer contact surface of the wear-resistant sealing strip (30) in contact with a scroll surface is flat, which improves performances of sealing and noise-reduction; a bottom surface of the wear-resistant sealing strip (30) is equipped with a sealing ring having a cross section in a shape of a circle or a circular tube, which improves the damping and buffering performances; thereby the performance of the air compressor is improved, and the use cost of the air compressor is also reduced.