Stabilized adaptive hydraulic system pressure in an injection molding system
AssigneeHusky Injection Molding Systems Ltd.
InventorsWeichun Yu, Gregory Allan Schultz
Life of this patent
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Abstract
In one aspect, there is provided an injection molding system configured to operate in a plurality of cycles. The system comprises, amongst other things, a controller that is configured for performing a comparison of a variable pressure setpoint with a target pressure value. The controller is configured to, when the target pressure value is less than the variable pressure setpoint by at least a predetermined lower bound, (i) decrease the variable pressure setpoint to a reduced variable pressure setpoint and (ii) not further decrease the variable pressure setpoint from the reduced variable pressure setpoint until the pump assembly operates for a plurality of stabilizing cycles at the reduced variable pressure setpoint.
Claims8
An injection molding system configured to operate in a plurality of cycles, the system comprising:
- a pump assembly;
- a proportional pump control valve operatively connected to the pump assembly;
- a sensor;
- and
- a controller,
- wherein the proportional pump control valve is configured to provide a variable pressure setpoint of the injection molding system equal to a magnitude of pressure of hydraulic fluid within the proportional pump control valve;
- wherein the sensor is configured to detect the magnitude of pressure hydraulic fluid within the proportional pump control valve and to send a signal to the controller representative of the variable pressure setpoint,
- wherein the controller is configured to control a flowrate of hydraulic fluid flowing out of the proportional pump control valve,
- wherein the variable pressure setpoint is configured to change based on the flowrate of hydraulic fluid flowing out of the proportional pump control valve,
- wherein the controller is configured to perform a comparison of the variable pressure setpoint with a target pressure value,
- wherein, upon performing the comparison of the variable pressure setpoint with the target pressure value, the controller is configured to, when the target pressure value is less than the variable pressure setpoint by at least a predetermined lower bound, (i) decrease the variable pressure setpoint to a reduced variable pressure setpoint and (ii) not further decrease the variable pressure setpoint from the reduced variable pressure setpoint until the pump assembly operates for a plurality of stabilizing cycles at the reduced variable pressure setpoint.
Dependencies are inferred from the claim text.