Friction based tool clamping mechanism for an injection molding machine comprises a wedge shaped clamp held on a tie bar by a hydraulic piston moving inside the moving platen

摘要

A wedge-shaped clamp(9) acting in conjunction with a corresponding piston(8) form part of a hydraulic locking system(3) by which the position of a moving tool carrying platen(2) or a third platen(7) is fixed relative to a tie bar(4) or a compression shaft. Independent claims are made for: a) an injection molding machine with the claimed friction mechanism for locking the moving tool clamping platen(2) position; b) a process for applying a closure force on the injection machine which involves operation of a closure cylinder(5) to move the moving platen towards the fixed platen(1) and close the tool(6a,6b) and locking the closed position of the tool using the claimed mechanism by filling an annular chamber with pressurized hydraulic fluid to force the piston(8) and thus the clamp onto the tie bar(4). A further increase in pressure in the annular chamber produces a clamping force on the tool.