A double-acting reciprocating motor with a uni-directional fluid flow path
comprises a piston disposed within a cylinder. Within the cylinder, the
piston defines a first chamber between the piston and a cylinder base and
a second chamber between the piston and a cylinder head. Fluid is
introduced into the first chamber of the motor through an inlet port
associated with the cylinder base. A pass-through valve controls the flow
of fluid from the first chamber to the second chamber. An outlet valve
regulates the draining of fluid from the second chamber through an outlet
port associated with the cylinder head. Fluid pressure within the first
chamber urges the piston towards the cylinder head when the pass-through
valve is closed and the outlet valve is open. The piston surface facing
the second chamber is larger than the piston surface facing the first
chamber, so the piston moves towards the cylinder base when the
pass-through valve is open and the outlet valve is closed. The
pass-through valve and the outlet valve are accessible without
disassembling the motor cylinder and may be electronically controlled
valves.