Intelli-Gent Mold TM the Intelligent Molding Solution

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1 1 Intelli-Gent Mold TM the Intelligent Molding Solution Intelli-Gent Mold TM Concept The process of Molding has changed considerably over the last decade relative to the microprocessor speeds of the Machines, use of servo valves, the implementation of electric injection and screw drives, expanded use of hot runner systems, more complicated molds, more demanding part applications and the proliferation of new Polymers. There has also been a considerable amount of work done on the best way to inject the polymer into the mold and more use of in-cavity sensors to control the movement of the screw ram. The Intelli-Gent Mold TM system addresses the use of a unique micro-bead melt sensor that indicates the imposed strains of temperature and radial force strain as a melt density K electro-motive force (emf) readout to determine the Screw Cutoff Position during the Pack Stage of a Decoupled II or Decoupled III molding strategy. Placement of the Temp-Tek TM Sensor (US patents #7,585,166 & 6,649,095) into the Nozzle body and cavity(s) will enable the molding machine to react to the Thermal Elastic Non-Newtonian properties of thermoplastics, promising 100% product verification. It s as simple as 1,2,3! Temp Tek TM Sensor Fig. 1a ( Cavity Sensor) The Temp-Tek TM Melt density sensor Fig. 1a takes the applied pressure (P) by the melt which compresses the sensor area (ᴨ D²) to decrease the bead volume (V). The radial force (F) generates a pressure emf (Pemf). The temperature (Temf) is generated from the bead dissimilar metal. A Fig. 1b temperature (Temf) and pressure (Pemf) is the actual thermocouple meter readout displayed on our 4S Temp Controller. The Temp-Tek TM Sensor can be used in place of a standard thermocouple and can be calibrated on a variety of scales for direct communication with a Injection Molding Machine (IMM). The small diameter of the sheathing (1mm) lends itself for placement into ejector pins, core pins, slides or directly into the cavity block itself. Temp Tek TM Sensor Control Chart PACK Phase 2 Te Hold Time (T) Cure time Total Area underneath the Curve = Mp value Temp Trigger Screw Stop (TTR) 1 TTR Fig. 2 3 TTR

2 2 Intelli-Gent Mold TM Theory The theory behind the process control logic of the Intelli-Gent Mold TM System was developed over many years using advanced sensing equipment and processing techniques by Frederick J. Buja, from his days at Kodak and has been enhanced by the invention of the Temp-Tek TM Melt Density Sensor Fig. 1a & 1b. The mold filling process can be improved by sensing the melt density of a Single Control Cavity (the lightest weight cavity of a multi-cavity mold) using One Temp Tek TM Sensor during 2nd stage pack and setting the Screw Inject Cutoff Position for precise part density. Using the Injection Molding Machine integrated with our 4-S Temp TM Controller and our Injection Molding Process Development step by step Guide for setting up a Decoupled II or III process, it s as simple as 1, 2, 3! 1. Using an appropriate scale, determine the lightest weight cavity (in a multi-cavity mold) using statistical analysis with a minimal sampling of 29 pcs. 2. Install a Temp-Tek TM Sensor into the last to fill / lightest weight cavity based upon your study above using an ejector pin or core pin Fig. 3 near the end of fill and connect the female mini-connector of the Sensor to control cavity #1 on the 4S-Temp TM Controller Fig. 4. The Sensor should be flush with the surface of the mold, there is no need to protrude the Sensor into the cavity space and our engineering staff will help determine the optimal placement. This cavity becomes the Control Cavity; the thermal template generated by filling this Cavity reflects the Sum of the energy needed to fill the cavity as well as the entire mold. 3. Experiment with second stage pack time and or position depending upon the age of the IMM to determine when a good shot is made, record the Temp-Tek TM readout at this point and set Temp Trigger TTR on the 4-S Temp Controller. Enable the 4S-Temp controller to control the IMM, TTR set point will close a relay to signaling Screw Forward Cutoff Position and the Thermal Energy/Density Template (Mp Value) Fig. 2 will signal if a Good-Bad part is made. Fig. 3, (Ejector Pin with thru-hole) Typical Cycle of Temp-Tek TM Readout Fig 4, (4-S Temp Unit)

3 Mold Startup/Setup with a new Tool 3 A complete systematic approach to Injection Molding Process Development for use with the 4S Temp Controller is offered when an Intelli-Gent Mold TM system is purchased and can be used to improve part quality of an existing tool or in the setup and development of a new tool, a brief explanation of the process is outlined below. Channel #1 Control Cavity Setup 1. Determine the velocity that is necessary for the Machine that the mold will be processed in so as to assure the optimal fill conditions with regard to fill time, fill pressure and resin temperature while using the nozzle body and tip selected for the mold. A systematic method for determining the correct velocity can be seen in our Viscosity section of our comprehensive guide. When trialing a mold for the first time it is best to execute a short shot progression so a calculation should be made on the volume of the mold vs. the volume of the injection cylinder so that the first shot will be approximately 80% filled. The subsequent shots should be increased and the fill progression observed until the parts are approximately 95-98% filled. Cavities should be labeled and part weights taken and recorded per the Cavity Imbalance section of the set up guide. If the cavity imbalance is greater than 5% then the mold should be sent back for modification of the gate and runner configuration. 2. When controlling with the Intelli-Gent Mold TM System, One Sensor/Channel should be used for Control and the selection of the control cavity should be the lightest weight cavity. If all cavities are balanced within 1% then any cavity can be used for the control cavity. Selecting the lightest weight cavity assures that once the control cavity is filled/packed, the other cavities will be packed as well. 3. Using the IMM controls, set the Inject Forward position transfer point from Fill to Pack so that the parts are between 95-98% filled. Observe the Temp Tek output at this position. 4. Using the IMM controls for a Decoupled II process, reduce second stage pressure and set Pack time. For a Decoupled III process, reduce the velocity and set the screw forward cutoff position. Through the use of visual techniques and part weight measurements observe the molded parts physical characteristics and make adjustments as necessary to complete the final filling of the cavity(s). Record the Temp-Tek TM readout at final screw cutoff position (note there will be additional melt inertia present in the cavity that is reflected on the 4-S Temp readout, this difference in Time/Temperature is shown in Fig. 2 as the range between set point TTR and maximum Temp Te) and Set Control Channel, Alarm #1 TTR Temp Trigger value to correspond with final screw cutoff position. Determine that parts pass quality inspection with TTR setting and proceed to item #5 below. Note that when TTR Temp Trigger is set the 4-S Temp Controller performs two actions; a. Closes/opens a digital relay, this relay is integrated with the IMM to signal Screw Forward Cutoff Position. b. A calculation is initiated starting at TTR to max Te to TTR set point, shrinkage. The area under this curve Fig. 2 represents the total Energy used to complete pack, hold and shrinkage in the control cavity. An Mp and Te value are recorded and displayed on the screen, these values are used to determine if a good-bad part is produced by setting a range for the values and closing/opening a digital relay when the value is off spec.

4 4 5. Conduct a statistical analysis for the next 29 shots (minimum) recording the max Te and Mp values. Use the statistical Mean of these values to set the control limits on the 4-S Temp Controller s Promote List. The min/max set points are factory set at +/- 3% of the Mean, when the molded part falls out of this range a digital relay is closed/ opened to signal an out of spec. part. The relay should be integrated to an in-house alarm signaling a bad part. 6. If pack and hold conditions can be established without clamp deflection or adverse effects then continue with the gate seal test in our Injection Molding Process Development Guide to determine the hold time necessary for gate freeze off, make adjustments as necessary after gate freeze off is established. 7. Good Parts are made when TTR Temp Trigger is met and the area between TTR, Te and TTR (Mp) and Te is within a set range. It s as easy as 1,2,3! Channel #2 Nozzle Sensor Setup 1. Alarm #1 TTR Temp Trigger = set point along the thermal curve that can be set at any point above the minimum temperature to record the thermal energy expended by the plasticating unit. The suggested set point should occur at the beginning of fill, the output, Mp value will display the energy used during the fill, pack, hold and shrinkage phase of the molding cycle. During machine idle time where there is the minimal Pressure emf (Pemf) the 4S Temp display will reveal the actual Melt Temperature of the polymer. The thermal curve and Mp output can be used for comparison over time to evaluate changes in the plasticating screw/barrel gap, screw tip (NRV) response time and dead head pressure resistance, heater band performance, use of the proper nozzle body Fig. 6 and tip, significant changes in melt viscosity of the material batch to batch and mold temperature. If a control batch of material is saved for comparison, an evaluation base point can be established for use to evaluate the mechanical components of the plasticating unit as detailed above. The output data can be used to make a determination on scheduling maintenance or on capital expenditures for these components. Fig. 6a Nozzle Body with Connector Fig. 6 Nozzle Body Temp Tek TM Nozzle Sensor 2. Alarm #2: An upper/lower control limit should be set to compare the Mp value for each cycle on the 4-S Temp Controller s Promote List. The Closure of the relay that is interfaced with an auxiliary alarm supplied by the customer is used to signal that the total shot used to fill the Mold is out of range. The use of this control output is different than the control cavity and the individual cavity sensors that are used for monitoring and it is unlikely Mp for the control cavity will be Good if the Mp for this channel is out of range. Using the Intelli-Gent Mold TM system to control the Mold final Pack Screw Cutoff Position is the most robust system designed for Injection Molding today. The unique Temp Tek TM Melt Density Sensor and 4S -Temp Controller assures 100% Molded part Control and Verification...it s as simple as 1,2,3!

5 The Intelli-Gent Mold TM Control System Parts List S Temp TM Video Recorder Bench Mount with Handle and Four Channels, Hz Supply, Ethernet and USB port for communication. 2. One Temp-Tek TM Melt density Sensor, 1mm diameter from 6-24 long and female Mini-Connector for insertion into Cavity with 12 long cable and female Mini-Connector. 4-S Temp TM Controller Electrical connection Schematic 3. One Temp-Tek TM Melt Density Nozzle Sensor with Brazed Fitting and female Mini-Connector for insertion into Nozzle with 12 long cable. 4.