Abstract: In an engine having free floating reciprocating pistons each with a cam follower which bears on a tri lobed cam, the pistons are arranged in one or more banks of four pistons each of which extends over an angular interval of 90.degree.. Where two banks of four pistons are utilized, the banks may be separated by an angular interval of 30.degree. or 90.degree.. The tri-lobed cam may be sinuously shaped with different profiles according to the desired characteristics of the engine.
Abstract: In an engine having free floating reciprocating pistons each with a cam follower which bears on a tri-lobed cam, each cam follower is supported by a guide bearing running in a track which serves to transmit to the track lateral reactive force components generated between the cam and the cam follower.