APPARATUS FOR CLAMPING OF MOLDING MACHINE

摘要

PURPOSE:To make a clamping part smaller and to obtain a defined clamping force with a smaller driving force, by providing a cam supported by a frame, contacting a contacting part and whose slope of the displacement curve is at first large and becomes smaller with progress of clamping. CONSTITUTION:The movable side mold 19 of a movable platen 12 is elevated by an air cylinder 13 to contact with a mold of the fixed side 18 and a cam 15 is pushed out by an air cylinder 17. A roller follower 14 is also pushed up and a defined clamping force is thereby generated. A molten resin or metal is injected from an injection nozzle 20 and is molded. The cam 15 is pulled back by the air cylinder 17 and the high pressure clamping is released. The movable platen 12 descends and opening of the mold is carried out. The part 15a of the cam 15 has a displacement curve represented by the equation (1) and the parts 15b and 15c have shapes represented by the equations (2) and (3). The cam 15 contacts the roller follower 14 at the part 15b and the contacted part moves to the part 15a. The clamping force thereby gradually increases. The slope of the part 15a becomes smaller with increase in the clamping force and the cam 15 can be thereby driven by a constant force. The clamping force reaches the defined force when the contacted part becomes to the part 15c.