Multi-parting molding system with clamping means

Abstract

A desynchronously opened, stacked, multi-parting molding system includes left, center and right molding blocks for defining a left molding cavity between the left and center molding blocks and a right molding cavity between the center and right molding blocks; a positioning mechanism for moving the left, center and right molding blocks along a common axis with respect to each other for desynchronously opening and closing the left and right molding cavities by retracting the first means and for simultaneously clamping both molding cavities in a closed position by protracting the first means, a locking mechanism for locking one molding cavity in a closed position while both molding cavities are clamped in a closed position and for maintaining the one molding cavity in a closed position while the other molding cavity is in an open position; and a clamping mechanism within at least one of the molding blocks that define the closed cavity provides axial clamping force while the first means is retracted to open the other molding cavity to the one molding cavity that is maintained in a closed position by the second means after the other molding cavity is opened. The axial clamping force is provided by expanding the thickness of at least one of the molding blocks that defines the one molding cavity. The clamping mechanism may be such as a spring for passively providing the axial clamping force. The clamping mechanism may be controllable, such as a controllable hydraulic cylinder, for actively providing the axial clamping force.