Injection molding apparatus and method for automatic cycle to cycle cavity injection

Patent metadata

Field	Value
Publication number	US-10875226-B2
Application number	US-201715724589-A
Country	US
Kind code	B2
Filing date	Oct 4, 2017
Priority date	Jul 20, 2016
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

An injection molding system comprising:
a first selected valve, one or more downstream valves, delivering a fluid to a mold cavity, at least one fluid property sensor, each valve associated with a position sensor that detects opening of a gate at an actual open gate time to the controller, the controller automatically adjusting time of instruction to open the gates on a subsequent injection cycle by an adjustment time equal to any delay in time between a predetermined open gate target time and an actual open gate time, wherein the system forms a first one or more parts or objects, the user inspecting or measuring the first one or more parts or objects and manually adjusts the predetermined open gate target time.

First claim

What is claimed is:

1. An injection molding system for initiating flow of fluid material into multiple gates of a mold cavity during an injection molding cycle, the system comprising:
a first selected valve comprising a first fluid flow passage having a first gate to the cavity, a first valve pin driven reciprocally along an axial upstream downstream path of travel through the first flow passage by a first actuator between gate open and gate closed positions,
one or more downstream valves, each downstream valve comprising a downstream fluid flow passage having a downstream gate to the cavity disposed downstream of the first gate, a downstream valve pin driven reciprocally along an axial upstream downstream path of travel through the downstream fluid flow passage by a downstream actuator between a gate open and a gate closed position,
at least one fluid property sensor mounted within the system such that the fluid property sensor detects, at a downstream detection time, a flow front of the fluid material flowing downstream through the mold cavity at a trigger location within the cavity disposed between the first gate and at least one selected downstream gate,
the fluid property sensor sending a first signal indicative of the downstream detection time to a controller,
the controller receiving the first signal and including a set of instructions that instruct the actuator of the valve associated with the at least one selected downstream gate to open the gate on a first injection cycle by withdrawing the valve pin from the gate closed position at an instruction time (X), the instruction time on the first injection cycle comprising a predetermined open gate target time (X) following the downstream detection time,
wherein the downstream valve associated with the at least one selected downstream gate further includes a position sensor that detects an actual open gate time upon withdrawal of the valve pin from the at least one selected downstream gate, the position sensor sending a signal indicative of the actual open gate time (A) to the controller,
the controller receiving the signal from the position sensor and including a set of instructions that automatically determines an automatic adjusted instruction time (X′) for use on a subsequent injection cycle, wherein the instructions that automatically determines comprises decreasing the time of instruction to the valve pin to open on the subsequent injection cycle by an adjustment time equal to any delay in time (Y) between the predetermined open gate target time (X) and the actual open gate time (A),
the controller receiving a second signal indicative of a manual adjustment (Q) of the predetermined open gate target time (X) for one or more of the valve pins on the subsequent injection cycle based on inspecting or measuring of a first one or more parts within the mold cavity during the first injection cycle,
the controller including instructions that determine and instruct the one or more valve pins on the subsequent injection cycle to open at an overall adjusted instruction time (X″) that includes or accounts for the automatic adjusted instruction time (X′) and the manual adjustment (Q).

2. The injection molding system of claim 1 , wherein the instructions are performed continuously over a plurality of subsequent injection molding cycles, and wherein the automatic adjusted instruction time of a subsequent cycle is determined by increasing or decreasing the adjusted instruction time (X′) of a prior cycle by an adjustment time equal to the difference in time between the actual open gate time of the prior cycle and the actual open gate time of a present subsequent cycle.

3. An injection molding system according to claim 1 further comprising one or more additional fluid property sensors associated with each downstream gate mounted within the system such that each additional fluid property sensor detects, at a downstream detection time, the selected property of the flow front of the fluid material flowing downstream at an additional trigger location within the cavity disposed between the first gate and each downstream gate,
each additional fluid property sensor sending a corresponding first signal indicative of the respective downstream detection time to the controller,
the controller receiving the corresponding first signals and including a set of instructions that instruct the actuator of the valve associated with each downstream gate to open the gate on the first injection cycle by withdrawing a corresponding valve pin from the gate closed position at a respective predetermined open gate target time (X) following the respective downstream detection time.

4. An injection molding system according to claim 3 wherein the fluid property sensor is a temperature sensor and the sensed property is temperature or change in temperature.

5. An injection molding system according to claim 1 wherein each of the one or more downstream valves includes an associated position sensor that detects an actual open gate time (A) upon withdrawal of the valve pin from the associated downstream gate, each associated position sensor sending a signal indicative of the sensed position of each corresponding valve pin to the controller, the controller receiving the signals from each of the associated position sensors,
the controller including a set of instructions that automatically determines the automatic adjusted instruction time (X′) by decreasing the time of instruction to the respective valve pin to open on a subsequent injection cycle by an adjustment time equal to any delay in time between the predetermined open gate target time (X) and the actual open gate time (A).

Assignees

• Synventive Molding Solutions Inc
• Synventive Molding Soliutions Inc

Inventors

• Moss Mark

Classifications

• B29C45/762 Primary

  the sequence of operations of an injection cycle · CPC title

• B29C2945/7607

  start · CPC title

• B29C45/77

  of velocity or pressure of moulding material · CPC title

• B29C2945/76876

  Switch-over · CPC title

• B29C2945/76043

  derivative, change thereof · CPC title