Patent ID: 7117828

Claim:
An axial motor comprising: a plurality of reciprocating thrust means arranged as opposed pairs in a substantially circular array about a central axis; a connecting rod for each thrust means pair connecting the thrust means in that pair, each connecting rod coincident with an axis extending through the respective thrust means pair it connects; a z crank coupled between the ends of an output shaft extending substantially coincident with the central axis, and comprising a crankshaft; and a power transmission apparatus comprising a z crank coupling coupled to the crankshaft of the z crank, a plurality of coupling support portions which are fixed relative to the z crank coupling, and a plurality of reciprocating coupling sliders, each engaged with a respective coupling support portion, wherein each coupling slider extends outwardly from the respective coupling support portion in a direction substantially transverse to the crankshaft and is reciprocable relative to the coupling support portion by means of a telescopic coupling and is connected to a corresponding connecting rod, wherein each coupling slider is adapted to transfer thrust from a corresponding thrust means pair to the z crank while reducing side thrust on the thrust means pair, by reciprocation relative to the respective coupling support portion in a direction substantially transverse to the crankshaft, with each coupling slider reciprocating relative to the respective coupling support portion by means of a sliding extending and retracting movement to compensate for movement in the transmission apparatus to retain each corresponding connecting rod substantially aligned with the axis extending through the respective thrust means pair it connects.