The thermal actuator can have a housing, a moving member, a sensing portion configured to move the moving member relative the housing when receiving heat from a source of heat, and a thermal insulator between the sensing portion and the source of heat.

The thermal actuator can have a housing, a moving member, a sensing portion configured to move the moving member relative the housing when receiving heat from a source of heat, and a thermal insulator between the sensing portion and the source of heat.

A piston assembly for a transmission includes a piston and a washer connected to the piston. In one embodiment, the washer includes a circumferential ring that extends continuously about an inner diameter, wherein a cavity is defined between the piston and the washer. A bearing element is retained and centered on the washer by the circumferential ring.

The invention relates to an imide polymer-based solid film lubricant, a method for producing same, a sliding element comprising same and the use thereof. According to the method, difunctional or cyclized difunctional compounds and optionally functional fillers are added to a non-imidized or partly imidized polyamide acid prepolymer or an imidized short-chain blocked prepolymer in a solvent or solvent mixture and then, depending on the prepolymer, a polymerization reaction or an imidization reaction and in both cases a crosslinking reaction is carried out. The solid film lubricant comprises an imide polymer as the resin matrix and optionally functional fillers, the molecules of the imide polymer comprising groups (R.sub.1) of the difunctional compounds that additionally contribute to the crosslinking.

A piston assembly for a transmission includes a piston and a washer connected to the piston. In one embodiment, the washer includes a circumferential ring that extends continuously about an inner diameter, wherein a cavity is defined between the piston and the washer. A bearing element is retained and centered on the washer by the circumferential ring.

A piston and cylinder assembly of an axial piston machine is disclosed which includes a cylinder having a uniform internal diameter, a cylindrical bushing press-fit against the inner surface of the cylinder and extending at least partially therein, the bushing comprising at least one circumferential groove formed on an outer surface of the bushing against the inner surface of the cylinder, a piston reciprocably disposed within the cylindrical bushing, generating a piston-bushing-interface, the piston and the bushing defining a diametrical clearance therebetween, the diametrical clearance defining a lubrication gap and a fluid-dynamic seal between the piston and the cylindrical bushing.

A piston and cylinder assembly of an axial piston machine is disclosed which includes a cylinder having a uniform internal diameter, a cylindrical bushing press-fit against the inner surface of the cylinder and extending at least partially therein, the bushing comprising at least one circumferential groove formed on an outer surface of the bushing against the inner surface of the cylinder, a piston reciprocably disposed within the cylindrical bushing, generating a piston-bushing-interface, the piston and the bushing defining a diametrical clearance therebetween, the diametrical clearance defining a lubrication gap and a fluid-dynamic seal between the piston and the cylindrical bushing.

A sliding contact assembly includes a first surface and a second surface. The second surface of the sliding contact assembly is configured to slide over the first surface, and at least a portion of the second surface contacts the first surface to form at an interface between the first surface and the second surface. The sliding contact assembly also includes a plurality of textures on the portion of the second surface that contacts the first surface. A density of the plurality of textures is not uniform over the portion of the second surface that contacts the first surface. The sliding contact assembly can include apex seal to housing interfaces in rotary engines, roller to roller interfaces, roller to housing interfaces, bearing to surface interfaces, etc.

A sliding contact assembly includes a first surface and a second surface. The second surface of the sliding contact assembly is configured to slide over the first surface, and at least a portion of the second surface contacts the first surface to form at an interface between the first surface and the second surface. The sliding contact assembly also includes a plurality of textures on the portion of the second surface that contacts the first surface. A density of the plurality of textures is not uniform over the portion of the second surface that contacts the first surface. The sliding contact assembly can include apex seal to housing interfaces in rotary engines, roller to roller interfaces, roller to housing interfaces, bearing to surface interfaces, etc.

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.