Method of purging shooting pot and providing enhanced purge capability
AssigneeHusky Injection Molding Systems Ltd.
InventorsJohn R. Galt, Anthony Paulovic, Jerzy Szajak, Uwe K. Melisch
Life of this patent
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Abstract
Methods for enhanced purging of an injection molding shooting pot assembly are provided. Old melt is purged from a shooting pot having an injection plunger slidably received in an injection cylinder. The plunger is moved by a powered piston, which moves the injection plunger to a purging position. The plunger is then arrested in the purging position. Sufficient new melt is injected through an inlet positioned such that the new melt sweeps substantially an entire volume of the injection cylinder ahead of the injection plunger in flowing between the inlet and a single outlet remote from the inlet.
Claims20
A method of purging old melt from a shooting pot having an injection plunger slidably received in an injection cylinder said plunger being moved by a powered piston, said method comprising the steps of:
- i) moving said injection plunger to a purging position;
- ii) arresting said injection plunger in said purging position;
- and
- iii) injecting sufficient new melt through an inlet positioned such that said new melt sweeps substantially an entire volume of said injection cylinder ahead of said injection plunger in flowing between said inlet and a single outlet remote from said inlet.
A method of purging old melt from a shooting pot having an injection plunger slidably received in an injection cylinder communicating with an injection nozzle and an extruder via a flow distribution controller, said method comprising the steps of:
- i) moving said injection plunger to a purging position;
- ii) arresting said injection plunger in said purging position;
- iii) adjusting said flow controller to a purging position;
- iv) injecting new melt from said extruder through a purging melt inlet communicating with said injection cylinder and formed by said flow controller;
- v) simultaneously using the injected new melt to purge old melt from said injection cylinder through a purging melt outlet communicating with said injection nozzle and formed by said flow controller;
- and
- vi) injecting sufficient new melt into said injection cylinder to purge said old melt through said melt outlet communicating with said injection nozzle.
A method of purging old melt from a shooting pot having an injection plunger slidably received in an injection cylinder communicating with an injection nozzle and an extruder via a flow controller, said method comprising the steps of:
- i) moving said injection plunger to a purging position;
- ii) arresting said injection plunger in said purging position;
- iii) adjusting said flow controller to a purging position;
- iv) injecting new melt from said extruder through an inlet communicating with said injection cylinder and formed by said flow controller;
- v) using the injected new melt to purge old melt from said injection cylinder through an outlet remote from said inlet and said injection nozzle;
- and
- vi) injecting sufficient new melt through said inlet into said injection cylinder to purge said old melt through said outlet remote from said inlet and said injection nozzle.
Dependencies are inferred from the claim text.