A piston and cylinder arrangement is disclosed in which a field of spaced pockets is provided on the walls of a piston skirt and/or the cylinder to create a seal equivalent between the piston and the cylinder. The pockets may be provided in a pattern having a plurality of vertically spaced rows.

Provided is a sliding component capable of stably reducing the frictional resistance of a sliding surface entailing eccentric rotation. A sliding component has a sliding surface relatively sliding with eccentric rotation, in which the sliding surface includes a land and a plurality of dynamic pressure generation mechanisms arranged in a circumferential direction, the dynamic pressure generation mechanism includes a shallow groove portion and a deep groove portion, and the shallow groove portion surrounds a circumference of the deep groove portion and communicates with the deep groove portion.

An engine housing includes a rotor housing and a side housing assembly. The rotor housing includes a rotor housing body. The rotor housing body extends about an axis to form a rotor cavity of the engine housing. The rotor housing body extends between and to a first axial end and a second axial end. The side housing assembly includes a side housing body, a side plate, and a seal assembly. The side housing body is disposed at the first axial end. The side plate is disposed axially between the rotor housing body and the side housing body. The side plate includes an inner side, an outer side, and a perimeter edge. The seal assembly includes a support ring and a sealing ring. The support ring is disposed at the perimeter edge and the first axial end. The support ring circumscribes the side plate. The sealing ring extends between and to a first axial sealing ring end and a second axial sealing ring end. The first axial sealing ring end is disposed at the support ring and the outer side.

A rotor housing for an aircraft rotary engine includes a side housing body and a rail. The side housing body extends along an axis between and to an inner side and an outer side. The side housing body forms a fluid cooling passage and a plurality of ribs. The fluid cooling passage extends about the axis at the inner side. The plurality of ribs are coincident with and extend into the fluid cooling passage. The plurality of ribs are distributed about the fluid cooling passage as an array of ribs. The rail is disposed at the plurality of ribs. The rail extends about the fluid cooling passage. The side housing body and the rail form a plurality of fluid cooling channels connected in fluid communication with the fluid cooling passage.

A pump, comprising a pump insert which is arranged in an accommodating space of a cup-shaped pump housing. The pump insert comprises a first housing part and a second housing part between which a rotor is rotatably arranged, and a stroke ring which surrounds the rotor and is arranged between the first housing part and the second housing part. A spring flexing along the rotational axis is arranged between the accommodating housing and the second housing part. The spring comprises a spring structure which is made of metal and which imbues the spring with its essential spring characteristics along the rotational axis. The spring is supported towards the second housing part in a region which is arranged in axial alignment with the stroke ring in the direction of the rotational axis, and thus presses the second housing part against the stroke ring.

A method of manufacturing a power unit for a downhole drilling motor includes fabricating a stator that provides two or more stator lobes that define an internal profile, and fabricating a rotor that provides at least one rotor lobe that defines an external profile that both rotates and precesses within the internal profile during operation. At least one of an external geometry and an internal geometry of the rotor along all or a portion of the rotor may be varied to alter a stiffness and mass of the rotor and thereby optimize stiffness and force balancing with respect to the stator. The rotor may then be rotatably positioned within the stator and thereby optimize the functioning and reliability of the motor power unit, of the downhole drilling motor assembly, of associated downhole drilling equipment, and to enhance directional drilling tendency modelling and directional drilling trajectory control.

The invention relates to a sealing arrangement (1) for conveying devices, in particular for gear pumps, in which an inner space (5) can be sealed off from an outer space (6), wherein the sealing arrangement comprises at least two parts (2, 3) each having at least one sealing surface (20, 21), wherein the sealing surfaces (20, 21) comprise: a first seal (11) along a first, medial perimeter of the sealing surface (20, 21), a second seal (12) along a second, lateral perimeter of the sealing surface (20, 21), a recess (15) between the first seal (11) and the second seal (12), characterized in that the recess (15) can be connected to a source (30) of a flushing medium such that the recess (15) can be actively flushed with the flushing medium.

A rotor for a rotary cylinder includes a body having a tube and a plate which has the first end integrally formed to the tube, and the second end of the plate extends radially relative to the tube. The plate is a solid plate and has a curved outer periphery. A first recessed area is defined in each of the top and the bottom of the plate. A waist is formed to the plate and located between the first and second ends of the plate. A resilient coat is coated to the body and includes a Y-shaped seal portion along the curved outer periphery of the plate so as to be movably in contact with the inside of the cylinder.

A rotary engine including a housing and housing head enclosing a combustion chamber, a piston including an output shaft and a piston disk within the housing and rotatable on a piston rotation axis, a quadrant within the housing and around the piston and rotatable on a quadrant rotation axis, wherein the quadrant rotation axis is acutely angled to the piston rotation axis, and a post surrounding a segment of the piston disk. The post pivots relative to the piston about a post-piston rotation axis that is normal to the face of the piston disk. The post pivots relative to the quadrant about a post-quadrant pivot axis that is perpendicular to the quadrant rotation axis. The post rotates about the quadrant rotation axis relative to the housing. Combusting fuel injected into the combustion chamber expands and pushes on the piston disk to rotate the output shaft about the piston rotation axis.

A supercharger assembly has a rotor housing defining a chamber. A rotor is within the chamber and has an end with an end face. A seal has a seal face adjacent the end face. The seal face and the end face have complex topographies configured to be complementary to define a gap therebetween. The complex topographies can be, but are not limited to, interfitting concentric annular channels. The gap functions as a tortuous flow path to inhibit fluid flow past the end face. A method of manufacturing a supercharger assembly is also provided.