US 6,056,536 A · Valve gating apparatus for injection molding

Abstract

A valve gating apparatus and method for injection molding includes at least one shutter disposed between the gate and the cavity melt channel into a mold cavity. The shutter is moved laterally, between a closed position wherein flow of melt from the nozzle into the cavity is inhibited, and an open position wherein flow of melt into the cavity is unimpeded by the shutter. Intermediate these two positions, the shutter can be employed to reduce the cross sectional area of the gate to throttle the gate. Embodiments are disclosed wherein one shutter or pairs of shutters are employed to gate the gate. Further, when pairs of shutters are employed, the shutters can abut each other in the close position or can overlie each other. This novel design prevents generation of waste material and eliminates the need to have devices for removing cold plugs.

Claims14

Dependent claims

A valve gating apparatus for a hot runner injection molding assembly having at least one injection molding nozzle mounted in a manifold plate and including a melt channel and a nozzle gate, said valve gating apparatus being positioned between the nozzle gate and a mold cavity, comprising:

at least one shutter positioned between said manifold plate and said manifold cavity and movable between a first position wherein said shutter inhibits flow of melt material from said nozzle gate and a second position wherein said nozzle gate is in fluid communication with said mold cavity, said shutter having a body with an aperture therethrough defining a melt flow path and a sealing edge, said aperture receiving a sealing post adjacent said nozzle gate therein, said sealing edge of said shutter abutting said sealing post in said second position to inhibit flow of melt and said sealing edge being distal said sealing post in said first position;
and,
means to move said shutter substantially perpendicular to the direction of melt flow through said nozzle gate between said first and second positions.

Dependencies are inferred from the claim text.

Valve gating apparatus for injection molding

Life of this patent

Valve gating apparatus for injection molding

Life of this patent

Abstract

Claims14