Injection Molding Clamping
A die clamping unit of an injection molding machine in which a molded piece is molded by injecting a material into injection molding dies, consists of a stationary platen and a movable platen. The stationary platen is fitted with a stationary die. The movable platen is fitted with a movable die. The movable platen is attached to the stationary platen by tie bars. The movable platen can advance toward and recede from the stationary die.
A die clamping unit includes hydraulic die clamping cylinders and tie bar sliding servomotors (halfnut positioning servomotors according to this invention). The hydraulic cylinders are provided on the stationary platen and advance and retreat the tie bars. The tie bar sliding servomotors advance and retreat the tie bars in their axial direction. The movable platen is advanced, and retreated on the tie bars by die opening/closing servomotors, and is anchored to the tie bars in a given position by die clamping halfnuts. In an injection pressing process, the hydraulic die clamping cylinders are driven to press the stationary and movable dies together.
Recent US Patents
1/18/2011
7,871,255
Injection molding machine
Kimura of Pascal Engineering, Japan, has developed an injection molding machine in which the molds are fixed in place by magnetic forces.
1/11/2011
7,867,415
Die clamping method
Koike et al of Toshiba, Japan,developed a die clamping unit for an injection molding machine consisting of a tie bar movably attached to a stationary platen, a halfnut positioning servomotor which advances and retreats to the tie bar, a halfnut which is provided on a movable platen and fixes the movable platen and the tie bar together by engaging the tie bar, an engaging mechanism which engages the halfnut with the tie bar, a hydraulic die clamping cylinder which presses the stationary platen and the movable platen, and a control device which controls the halfnut positioning servomotor and the hydraulic cylinder. (RDC 7/22/2011)