Heavy duty axial piston, swashplate pump or motor - has spherically shaped cylinder clearance space and cylinder block walls bulged locally

摘要

The heavy duty axial piston, swashplate type, pump/motor is conventional with a rotating cylinder block in which pistons reciprocate by virtue of being movably mounted in a plate set at an angle to the cylinder block axis. However that part (18) of each cylinder into which the piston does not enter has a spherical surface, and is connected to the end opening (14) by a smooth curve. To maintin an even wall thickness, the outside surface of the block is bulged out concentrically in that vicinity (27). Alternatively a reinforcing strap, the same width as the bored-out part of the cylinder, is fitted around the block.