Crosshead

—In engineering, the connection between the piston and connecting rods of a reciprocating engine. With marine engines of moderate size, and many small motors, it is sometimes an enlargement of the piston rod. In stationary and locomotive work, it is usually a separate steel casting, having a taper socket into which the piston rod is cottered, with a separate pin through the jaws of a double eye to serve as a gudgeon on which the connecting rod vibrates. In large marine engines, it is a steel block into which the piston rod is bolted, a projecting arm on either side affording attachment for the forked end of the connecting rod.