Closed Loop Control for an Injection Unit
AssigneeHusky Injection Molding Systems Ltd.
InventorGong ZHANG
Life of this patent
Estimating the term…
Abstract
A method is provided for improving melt quality in an injection unit. A closed loop control system regulates operation of the injection unit in accordance with a reference value for at least one operating parameter. A sensor measures the present value of a load upon the motor which drives an injection screw during operation of the injection unit. A processor compares the present value of the load to a reference value for the load. If the present value of the load deviates from the reference value of the load by more than a predetermined amount, then the processor adjusting the reference value of the at least one operating parameter. Operating parameters can include barrel temperature, back pressure and screw RPMs.
Claims30
A method for improving melt quality in an injection unit, comprising:
- regulating operation of the injection unit in accordance with a reference value for at least one operating parameter;
- measuring a present value of a load upon a motor operable to rotate an injection screw during operation of the injection unit;
- comparing the present value of the load to a reference value for the load;
- and
- if the present value of the load deviates from the reference value of the load by more than a predetermined amount, then adjusting the reference value of the at least one operating parameter.
An injection unit, operable to:
- regulate its operation in accordance with a reference value for at least one operating parameter;
- measure a present value of a load upon a motor operable to rotate an injection screw during the operation of the injection unit;
- compare the present value of the load to a reference value for the load;
- and
- if the present value of the load deviates from the reference value of the load by more than a predetermined amount, then adjust the reference value of the at least one operating parameter.
Dependencies are inferred from the claim text.