A piston unit for coupling to a crosshead piston rod with a crosshead piston pin includes a piston crown member and an integrated crosshead pin support and skirt member. The piston crown member consists essentially of forged steel. An integrated crosshead pin support and skirt member consists essentially of forged steel. The integrated pin support and skirt member is affixed to the piston crown member and is configured to support the crosshead piston pin. In a method of making a crosshead piston, a piston crown member is forged from steel. An integrated crosshead pin support and skirt member is forged from steel. The piston crown member is welded to the integrated crosshead pin support and skirt member.

A piston unit for coupling to a crosshead piston rod with a crosshead piston pin includes a piston crown member and an integrated crosshead pin support and skirt member. The piston crown member consists essentially of forged steel. An integrated crosshead pin support and skirt member consists essentially of forged steel. The integrated pin support and skirt member is affixed to the piston crown member and is configured to support the crosshead piston pin. In a method of making a crosshead piston, a piston crown member is forged from steel. An integrated crosshead pin support and skirt member is forged from steel. The piston crown member is welded to the integrated crosshead pin support and skirt member.

A compressor assembly for a compressed-air feed of a compressed-air supply system for operating a pneumatic system includes a compressor having a con-rod, a con-rod bearing, and a cylinder. The con-rod has a compressor piston. The compressor assembly further includes a drive having a drive shaft and a drive housing. The drive shaft is mounted in a drive bearing that is disposed within the drive housing. The drive bearing and the con-rod bearing partially or completely overlap one another in the axial direction, or the axial central plane of the drive bearing and the axial central plane of the con-rod bearing lie in one bearing plane. A crank disk is fixedly connected to an end portion of the drive shaft, the crank disk having a con-rod receptacle portion that is disposed so as to be eccentric to the drive shaft, the crank disk being rotatably connected to the con-rod.

The disclosure provides rotary machines that include, in one embodiment, a shaft defining a central axis A, the shaft having a first end and a second end. The shaft can have a first gearbox disposed thereon defining one or more cavities therein. At least one contour is slidably received into an arcuate cavity in an exterior surface of the gearbox. The contour has a convex outer surface that cooperates with an inwardly facing curved surface of a housing to form a working volume. A gearbox mechanism consisting of gears, crankshafts, bearings and connecting rod creates an oscillatory motion 2 times per revolution such that the contour can navigate about the arcuate cavity without contacting the cavity at a high rate of rotating speed. Thus, said working volume can expand and compresses twice per rotatable shaft revolution.

The disclosure provides rotary machines that include, in one embodiment, a shaft defining a central axis A, the shaft having a first end and a second end. The shaft can have a first gearbox disposed thereon defining one or more cavities therein. At least one contour is slidably received into an arcuate cavity in an exterior surface of the gearbox. The contour has a convex outer surface that cooperates with an inwardly facing curved surface of a housing to form a working volume. A gearbox mechanism consisting of gears, crankshafts, bearings and connecting rod creates an oscillatory motion 2 times per revolution such that the contour can navigate about the arcuate cavity without contacting the cavity at a high rate of rotating speed. Thus, said working volume can expand and compresses twice per rotatable shaft revolution.

A piston assembly includes a piston head. The piston assembly further includes an upper connecting rod rotatably coupled to the piston head. The piston assembly also includes a shoe positioned between the upper connecting rod and an inner wall of the piston head.

A piston assembly includes a piston head. The piston assembly further includes an upper connecting rod rotatably coupled to the piston head. The piston assembly also includes a shoe positioned between the upper connecting rod and an inner wall of the piston head.

A piston assembly, piston therefor and methods of construction are provided. The assembly includes a piston head and connecting rod operably coupled thereto via a wrist pin. The piston head has an upper crown with a combustion bowl and an undercrown surface. The lower crown includes axially aligned pin bores receiving the wrist pin. An upper wall of the lower crown has an oil inlet, an oil outlet and a concave, saddle bearing surface that bears against the wrist pin. A toroid-shaped outer cooling gallery is formed between wall portions of the upper and lower crowns, wherein the outer cooling gallery surrounds an inner cooling gallery. The connecting rod is fixed to the wrist pin for conjoint oscillation. The connecting rod has an oil passage in fluid communication with a through hole in the wrist pin to allow oil to flow therethrough into the inner cooling gallery via the oil inlet.

A piston assembly, piston therefor and methods of construction are provided. The assembly includes a piston head and connecting rod operably coupled thereto via a wrist pin. The piston head has an upper crown with a combustion bowl and an undercrown surface. The lower crown includes axially aligned pin bores receiving the wrist pin. An upper wall of the lower crown has an oil inlet, an oil outlet and a concave, saddle bearing surface that bears against the wrist pin. A toroid-shaped outer cooling gallery is formed between wall portions of the upper and lower crowns, wherein the outer cooling gallery surrounds an inner cooling gallery. The connecting rod is fixed to the wrist pin for conjoint oscillation. The connecting rod has an oil passage in fluid communication with a through hole in the wrist pin to allow oil to flow therethrough into the inner cooling gallery via the oil inlet.

A pin including recesses extending longitudinally between opposite ends, and a piston assembly including the pin, for a two-stroke engine, is provided. The recesses preferably have a radius of curvature less than a radius of curvature of the remaining outer surface of the pin. The pin is rotationally fixed relative to the connecting rod. As the connecting rod swings back and forth during operation, some of the recesses rotate beyond the load bearing region of the pin joint where oil is located, allowing oil to fill the recesses. As the pin swings back, these recesses carrying the oil enter the load bearing region of the pin joint, transferring the oil with them. Preferably, at least one of the recesses aligns with an oil opening in the pin, which aligns with an oil hole in the connecting rod, to receive and distribute oil along the full length of the pin.