Slide cylinder

A slide cylinder including a cylinder block internally defining a plural number of parallel cylinder bores, piston rods extended through said cylinder bores, and pistons fixedly mounted on said piston rods in said cylinder bores, said pistons defining first and second drive chambers on the opposite sides thereof, said slide cylinder comprising:

• communicating passages formed in said cylinder block, one intercommunicating said first drive chambers and the other intercommunicating said second drive chambers;
• a first fluid supply/discharge passage formed axially through a first one of said piston rods in communication with said first drive chamber;
• a second fluid supply/discharge passage formed axially through a second one of said piston rods in communication with said second drive chambers;
• a first fluid supply/discharge port formed in said cylinder block in communication with one of said first drive chambers;
• a second fluid supply/discharge port formed in said cylinder block in communication with one of said second drive chambers;
• said first and second drive chambers being selectively connectable to a source of pressurized fluid through one of said first and second fluid supply/discharge ports or through fluid supply/discharge ports at the opposite ends of said fluid supply/discharge passages in said piston rods;
• plate-like cross members integrally connecting said piston rods at the opposite ends thereof;
• and
• fixing means provided on said cylinder block and cross members and selectively used for fixing said slide cylinder,
• wherein each of said piston rods is made of a straight continuous, one-piece, bar-like material having stopped grooves, wherein each said piston includes cylindrical portions fitted to one of said piston rods with ends of saud cylindrical portions of the piston being caulkingly fitted in said stopper grooves to fasten said piston to said one of said piston rods, said stopper grooves being provided at portions of said one of said piston rods corresponding to positions of ends of said cylindical portions of said piston, and wherein said ends of said cylindrical portions of said piston are pressed against outer edges of said stopper grooves.