Valve gate system
OwnerPanos TRAKASinventor
Life of this patent
Estimating the term…
Abstract
A valve gate assembly comprises a piston that is actuable between a forward position and a rear position and has a piston stop surface and a forward pressure surface. A cylinder has a cylinder stop surface that is disposed to contact the piston stop surface when the piston is in the forward position. The cylinder stop surface is radially outward of at least a portion of the forward pressure surface and a shutoff pin is substantially aligned with the axis.
Claims12
A method of in situ purging of a shutoff valve of an injection molding apparatus comprising the steps of
- providing a chamber to be axially rearward of a manifold shutoff pin hole, the shutoff pin hole opening onto the chamber, a forward surface of a piston defining a rearward surface of the chamber;
- accumulating debris in the chamber, the debris resulting from polymer flowing from a polymer melt flow bore through the shutoff pin hole into the chamber;
- positioning the piston in a purging position;
- flowing a purging fluid from a purging supply port into the chamber;
- and
- exhausting the purging fluid and debris out of an exhaust port in fluid communication with the chamber.
A valve gate assembly for injection molding, comprising:
- a clamp plate having
- a first bore having an axis and a first diameter;
- a second bore adjacent to and forward of the first bore, aligned with the axis, and having a second diameter larger than the first diameter;
- a cylinder having a third diameter larger than the first diameter but smaller than the second diameter, the cylinder being insertable into the second bore;
- a piston being insertable into the cylinder through the first bore and actuable along the axis between a forward position and a rear position, the piston having a rear piston stop surface, a gate shutoff pin aligned with the axis and affixed to the piston;
- and
- a cover plate disposed rearwardly of the rear piston stop surface and having a cover plate stop surface disposed to contact the rear piston stop surface with the piston in the rear position.
A method of adjusting the stroke of a piston of a valve gate assembly comprising the steps of:
- providing a valve gate assembly including a cylinder and a piston actuable along an axis within the cylinder between a forward position and a rear position, the piston having a rear piston stop surface;
- providing a plurality of cover plates, each cover plate having at least one leg, said at least one leg having with a predetermined length and a cover plate stop surface, the cover plate stop surface contacting the rear piston stop surface with the piston in the rear position;
- and
- adjusting the stroke of the piston by replacing a first cover plate having a leg of a first predetermined length with a second cover plate having a leg of a second, different predetermined length.
Dependencies are inferred from the claim text.