Bolt-on piston assembly

Claim 1

A bolt-on piston assembly comprising a piston rod having an integral portion projecting radially on said rod, two endlessly circular piston pieces encircling said rod and being disposed on axially opposite sides of said portion and with said pieces each having a surface respectively faced toward said portion to be clamped relative thereto and be axially fixed relative to said rod, said piston pieces each having an outer diameter greater than the outer diameter of said portion to extend radially beyond said portion, said pieces being entirely separated from one another by a space, one of said piston pieces having a section thereof extending axially of said rod and axially over said portion, the surface of said one piston piece being in axial abutment with said portion, the axial length of said section being less than the axial length of said portion for effecting clamping of said pieces onto the projecting said portion and have said pieces without movement axially of and relative to said rod, engagement means interposed between said surface of said other piston piece and said portion, bolts extending into said piston pieces radially beyond said portion for releasably securing said piston pieces on said portion to be axially fixed relative thereto for attaching said piston pieces onto said rod, and a seal member disposed in said space between said piston pieces at the outer diameters of said piston pieces.