Abstract: An engine piston composed of a head and a body separately formed from the head. The head is of ceramic material and the body is light metal or light alloy. The head and the body are connected against axial movement by interengagement of inclined surfaces on the head and body by rotation of the head relative to the body, and the head and body are then fixed against relative rotation by an anti-turning device, this arrangement preventing development of excessive thermal stress. The piston is of reduced weight, can be mass-produced, and reduces fuel consumption.

Abstract: A piston rod is formed of fiber reinforced material so arranged that an elastic connecting zone is provided between the rod and the piston, thereby avoiding bolting one end of the piston rod to the piston. The cavity inside the piston has a dovetail recess. The fibers are anchored in the cavity and recess by embedding the fibers, which fan out in a uniform distribution from said elastic connecting zone, in a synthetic embedding material.

Abstract: The piston of a piston-type machine has on its surface a heat-barrier layer of plastic material which is cast into a recess formed in the piston crown. A pouring means formlockingly enclosing the upper edge is put on the piston, held in a vertical position, to permit the recess to be overfilled with the material. The pouring means is removed after the material has hardened. Due to the shrinkage of material when the material hardens, the material and the upper edge form a flat surface on the piston.

Abstract: A composite piston for internal combustion engines is provided. The base structure of the piston is formed from a fiber-reinforced resin material. Covering the head portion of the base structure and integral therewith is a cap portion formed of a nonflammable material such as metal, metal alloys and ceramics. The cap and head portion of the piston have an outer diameter which is less than the outer diameter of the piston body by an amount sufficient to accommodate for the difference in the thermal coefficient of expansion of the material of the cap and the material of the base structure.

Abstract: The disclosure illustrates an insulated composite piston comprising a crown of ceramic or other heat resistant material secured to an aluminum piston body by a bolt of temperature resistant alloy. A low conductivity interface between the crown and the body is provided by a series of stacked discs having low effective thermal conductivity. The relative thermal expansion of the parts is compensated for by bellville washers on the bolt. The above arrangement insulates the crown from the piston body thereby minimizing the temperature gradient across the crown so that its temperature can be maintained as high as necessary to increase efficiency and minimize noxious emissions.

Abstract: A plastic disc brake piston is disclosed with a novel fluted inner core design, giving a piston with superior structural strength, crack resistance, and improved heat dissipation when used in disc brake assemblies.

Abstract: A piston having a floating wedge carried in a recess of the skirt for limited axial movement. Reciprocation of the piston shifts the wedge position between upper and lower extremes, reducing the effective piston clearance in its cylinder during the upper portions of its stroke, thus reducing lateral piston motion and resulting piston slap caused noise.

Abstract: An internal combustion engine crosshead piston assembly having an outer skirt elastomerically mounted on an inner skirt to reduce piston-slap-caused noise.

Abstract: An internal combustion engine crosshead piston assembly having an outer skirt mounted by an elastomeric member on an inner skirt to reduce piston-slap-caused noise wherein expansible chambers are provided in the elastomeric member and are connected by orifices in the inner skirt to receive and eject oil to provide cooling of the outer skirt and also add a damping effect to further reduce the noise.

Abstract: An impact drive tool has a cylinder within which a percussive piston is mounted for actuating a ram to drive a nail into a workpiece. Valve means are provided for introducing compressed air to one side of the piston to cause the impact stroke, and an air storage chamber is provided for returning the piston to its rest position. A truncated cone shaped first buffer element of a cellular polyurethane is affixed to the bottom of the percussive piston. A second buffer element of a harder material, such as a cross-linked polyurethane is mounted in the bottom of the cylinder. The second buffer element has a recess facing the first buffer element and shaped to receive the first element. The buffer elements are positioned so that, at the end of an impact stroke, the first buffer element is initially deformed, followed by the striking of a bottom portion of the piston on the second buffer element to absorb the impact energy.