Abstract: A piston ring providing improved performance during operation, including reduction in blowby gases and improved oil control, is provided. The piston ring includes an upper layer, a lower layer, and a middle layer each formed from a powder metal material. An exposed sharp first corner is present between an upper ring surface and an upper outer diameter surface, and an exposed sharp second corner is present between a lower ring surface and a lower outer diameter surface. The piston ring also comprises a coating including diamond-like carbon (DLC). The DLC coating is inlaid. Thus, the coating is disposed on the middle layer but is spaced from the upper and lower corners, so that the upper and lower corners of the piston ring are exposed.

Abstract: An insert for a cylinder liner which is capable of trapping heat in the combustion chamber is provided. The insert extends circumferentially around a center axis and longitudinally from an upper end to a lower end. The insert includes an inner portion presenting an inner surface facing the center axis and an outer portion presenting an outer surface facing away from the center axis. The inner portion is formed of an iron-based material, such as steel, and the outer portion is formed of a material having a thermal conductivity of not greater than 3.5 W/mK, for example ceria stabilized zirconia. The inner and outer portions each present a thickness, and the thickness can form a gradient between the upper end and the lower end of the insert. For example, the thickness of the outer portion can be greater at the upper end than at the lower end of the insert.

Abstract: A piston ring providing improved performance during operation, including reduction in blowby gases and improved oil control, is provided. The piston ring includes a rail disposed in a recess of a wire. The wire presents a wire outer diameter surface, the ring presents a ring outer diameter surface, and a coating including diamond-like carbon is disposed on the rail outer diameter surface. The coating is inlaid and thus an exposed sharp upper corner is present between an upper portion of the wire outer diameter surface and an upper ring surface, and an exposed sharp lower corner is present between a lower portion of the wire outer diameter surface and a lower ring surface.

Abstract: A piston ring providing improved performance during operation, including reduction in blowby gases and improved oil control, is provided. The piston ring includes an upper layer, a lower layer, and a middle layer each formed from a powder metal material. An exposed sharp first corner is present between an upper ring surface and an upper outer diameter surface, and an exposed sharp second corner is present between a lower ring surface and a lower outer diameter surface. The piston ring also comprises a coating including diamond-like carbon (DLC). The DLC coating is inlaid. Thus, the coating is disposed on the middle layer but is spaced from the upper and lower corners, so that the upper and lower corners of the piston ring are exposed.

Abstract: An insert for a cylinder liner which is capable of trapping heat in the combustion chamber is provided. The insert extends circumferentially around a center axis and longitudinally from an upper end to a lower end. The insert includes an inner portion presenting an inner surface facing the center axis and an outer portion presenting an outer surface facing away from the center axis. The inner portion is formed of an iron-based material, such as steel, and the outer portion is formed of a material having a thermal conductivity of not greater than 3.5 W/mK, for example ceria stabilized zirconia. The inner and outer portions each present a thickness, and the thickness can form a gradient between the upper end and the lower end of the insert. For example, the thickness of the outer portion can be greater at the upper end than at the lower end of the insert.

Abstract: A piston ring assembly for sealing a cylinder wall to a piston body is provided. The piston ring assembly includes a plurality of rings stacked in an axial direction one in abutment with another. Each ring has an inner face and an outer face. The piston ring assembly also includes a spring which substantially circumferentially surrounds the stacked rings and abuts the outer faces of the rings. The spring biases the stacked rings in a radially inward direction for sealing the inner faces of the rings against the piston body. The spring may be of a strip of material bent into a serpentine pattern when in an at rest condition to apply the biasing force against the piston body.

Abstract: A power cylinder assembly for an internal combustion engine is provided. The power cylinder assembly includes a cylinder wall having a channel formed therein and a piston body with a skirt. A piston ring is seated within the channel of the cylinder wall and is sealed against the skirt of the piston body. Specifically, the piston ring has a ring body with an inner face that presents two radially inwardly extending ridges spaced axially from one another by a valley region, and the outer face presents a groove which receives a spring to bias the ridges into sliding engagement with the outer surface of the skirt of the piston body. The ring body also has at least one oil drainage port which extends radially between the valley region of the inner surface and the groove of the outer face for conveying oil from between the ridges into the groove.

Abstract: A piston ring for sealing a cylinder wall to a piston body is provided. The piston ring includes a ring body of an elastically deformable material which extends substantially circumferentially around an axis and has an inner face that faces the axis. The inner face includes a plurality of axially spaced and radially inwardly extending contact features. The ring body configured to bias the contact features into engagement with the piston body to establish a seal therebetween. At least one of the contact features extends substantially continuously around a circumference for establishing a substantially continuous seal around the piston body, and at least one of the contact features is non-continuous and has at least one recessed area for allowing the passage of oil and gas therethrough.

Abstract: A piston ring for sealing a cylinder wall to a piston body is provided. The piston ring includes a ring body that extends about an axis and has inner and outer faces. The inner face presents a pair of ridges that extend in a radially inward direction, and the outer face presents a groove. A spring of an elastomeric material substantially circumferentially surrounds the ring body and is seated in the groove on the inner face. The spring biases the ring body in the radially inward direction to seal the ridges against the piston body. The ring body also has at least one oil drainage port which extends at an angle relative to the radially inward direction from the inner face to a location on the outer face on one axial side of the spring for conveying oil out of a space between the ridges.

Abstract: A cylinder liner includes a body formed of a metal material extending circumferentially around a center axis with an outer surface facing away from the center axis. A thermal barrier coating including an insulating material having a thermal conductivity of not greater than 5 W/(m·K) is applied to the outer surface. The thermal barrier coating is thermally applied to the outer surface at a velocity of 100 to 1,000 m/s, for example by a high velocity oxygen fuel (HVOF) spray, a plasma spray, or a detonation gun.

Abstract: An apparatus and method for measuring brake bias in a brake system on a vehicle includes a brake bias measuring pad, such that the brake bias measuring pad is operatively positioned within a brake caliper in the brake system. The apparatus also includes a load measuring mechanism disposed within the brake bias measuring pad, such that the load measuring mechanism measures a load applied by a brake caliper piston on the brake bias measuring pad. The method includes the steps of measuring a load applied by a brake caliper piston on a brake bias measuring pad operatively positioned within a brake caliper in a brake assembly of the brake system. The method also includes the steps of determining a brake caliper pressure based on the load applied by a brake caliper piston on the brake bias measuring pad and determining a load in the brake caliper based on the caliper pressure.