Power cylinder construction

Claim 1

In a power cylinder a body fabricated from a cylindrical tube of uniform cross section having a cylindrical bore; said body having a fixed end cap at one end; a gland end cap having an elongated cylindrical body slidable fitted within said cylindrical bore at the open end of said tubular body; said cylindricaL body having axially separated external annular grooves adjacent to its respective ends; annular seal means in said grooves for sealing said gland body relative to said tubular body; said gland cylindrical body having a third outward facing annular groove; said tubular body having one or more radial threaded holes for communication with said third annular groove; screw means threaded into said holes and extending into said third annular groove to retain said gland end cap; said gland end cap having a central axial bore for accommodating a piston rod, and including two axially spaced annular grooves opening to said piston rod bore; V-type annular seal means in the axially inner groove producing a sliding pressure seal between said gland and said piston rod; and annular wiper means in said axially outer groove for cleaning the piston rod surface; a piston rod having a reduced diameter end section defining a shoulder for accommodating an annular piston assembly attached thereto for reciprocation within said cylindrical bore; a piston assembly comprising a unitary annular disk-like member having a central bore dimensioned to be fitted over the reduced diameter end section of said piston rod, and having axially spaced peripheral annular grooves, and V-type annular piston packing members in said grooves for engagement with the cylindrical bore of said tubular body.