Abstract: In a fluid tensioner for a camshaft drive belt, a piston rod is sealed by a flexible diaphragm having an enlarged inner end clamped in a conforming groove in the piston rod by a spring clamp. This maintains the inner end of the diaphragm at a fixed position on the piston rod, and provides a labyrinthine seal preventing leakage of fluid. A flattened portion of the piston rod fits a D-shaped opening in a cap to prevent rotation of the piston rod and premature failure of the seal. A dust seal located on the cap also has a D-shaped hole, aligned with the D-shaped hole in the cap, and conforming to the flattened part of the piston rod.

Abstract: A frictional transmission chain, comprising: an endless transmission chain formed from link plates and link plate connection pins; a plurality of frictional V blocks, each having a hollow interior through which a portion of the endless transmission chain extends, each having inner lateral surfaces with holes therein for receiving opposite ends of at least one of the connection pins, and each having inclined, generally trapezoidal outer lateral surfaces; and, frictional transmission contact surfaces of a generally V-shaped configuration, transversely symmetrical about a centrally disposed recessed portion, and projecting radially from the outer inclined lateral surfaces with respect to a V-groove pulley with which the transmission chain is adapted to tightly frictionally engage by means of the V blocks, power being transmitted along the chain only by the link plates and connection pins of the endless chain, each of the V blocks transmitting power only between its respective at least one connection pin and the

Abstract: A surface hardened pin for a chain is made from a ferrous alloy containing manganese, silicon, chromium, molybdenum and about 0.1 to 0.4% carbon, with the balance essentially iron. The layer is formed of ferrous material containing chromium and 0.6 to 0.9% carbon and has a plurality of carbide particles dispersed therethrough. The hardened surface layer is formed by gas carburizing the pin.