CONTROL SYSTEM FOR INJECTION MOLDING

1 . An apparatus comprising:

a barrel connected to a hopper for receiving a material from the hopper;

one or more heaters outside the barrel;

an extrusion screw inside the barrel;

a motor coupled to one end of the extrusion screw to rotate the extrusion screw;

a torque sensor on the motor; and

a controller coupled to the motor and the heaters, the controller configured to receive signals from the torque sensor, the controller comprising a control algorithm to adjust the one or more heaters according to the signal from the torque sensor to melt the material inside the barrel.

2 . The apparatus of claim 1 , further comprising strain sensors attached to the frame that supports a mold.

3 . The apparatus of claim 1 , further comprising thermal sensors inside the barrel.

4 . The apparatus of claim 1 , further comprising pressure sensors inside the mold and a back pressure sensor attached at the end of the extrusion screw.

5 . The apparatus of claim 1 , wherein the controller comprises a display as a user interface.

6 . The apparatus of claim 1 , further comprising a wireless device in communication with the controller.

7 . The apparatus of claim 1 , wherein the controller comprises a processor and a memory device.

8 . The apparatus of claim 1 , wherein the controller comprises a network interface.

9 . The apparatus of claim 1 , further comprising a camera for capturing images or videos in communication with the controller to help remote trouble shooting.

10 . An automatic control method for a molding system, the method comprising:

receiving a material type and a part size in a controller including a control algorithm;

selecting operating parameters by the control algorithm according to the material type and the part size, the operating parameters comprising a barrel temperature and a screw rotation speed;

switching on one or more heaters to heat a material inside the barrel to the selected barrel temperature;

activating a motor to rotate an extrusion screw inside the barrel at the selected screw rotation speed, the motor being coupled to an end of an extrusion screw inside a barrel;

adjusting the one or more heaters to melt the material; and

molding a part.

11 . The method of claim 10 , the operation of adjusting the heaters comprising:

determining if the material comprises a temperature sensitive material based upon a database; and

adjusting the one or more heaters when the temperature sensitive material is confirmed.

12 . The method of claim 10 , the operation of adjusting the heaters comprising:

analyzing to determine if the material comprises a semi-crystalline polymer based upon a database; and

deactivating at least one of the one or more heaters when the semi-crystalline polymer is confirmed.

13 . The method of claim 10 , the step of molding a part comprising rotating the extrusion screw by one of a number of screw rotations and a screw rotation time selected according to the part size.

14 . The method of claim 10 , the operation of adjusting the heaters comprising:

rotating the extrusion screw to pump the material at the selected barrel temperature into a mold at to the selected screw rotation speed;

determining if the material temperature inside the barrel is high enough for molding from a torque sensor on a motor coupled to an end of the extrusion screw; and

adjusting the heaters.

15 . The method of claim 14 , the operation of determining if the material temperature is high enough, further comprising:

analyzing the torque load data from the torque sensor; and

adjusting the heaters until the torque load achieves a predetermined value.

16 . The method of claim 15 , the operation of analyzing the torque load data from the torque sensor received in the controller, further comprising disregarding spike signals until a predetermined stress load on the frame is achieved, the stress load being measured by a strain sensor on a frame housing an extrusion system and a mold system.

17 . The method of claim 10 , the operation of molding a part comprising:

receiving a signal from a machine in an assembly line to mold a part;

clamping a mold;

opening a nozzle to allow the material to flow into the mold;

continuously rotating the extrusion screw to pump the material into the mold;

determining if the mold is filled;

closing the nozzle to prevent the material from flowing into the mold;

cooling the mold; and

unclamping the mold to release the part.

18 . The method of claim 17 , wherein an injection pressure in the barrel is substantially the same or up to 10% higher than a pressure in the mold.

19 . The method of claim 10 , the operation of molding a part comprising:

clamping a mold;

activating the motor to rotate the extrusion screw to move the extrusion screw backward to open a nozzle to allow the material to flow into the mold;

continuously rotating the extrusion screw to pump the material at the adjusted temperature into the mold;

determining if the mold is filled;

reversing the motor to rotate the extrusion screw to move the extrusion screw forward to shut off the nozzle;

cooling the mold; and

unclamping the mold to release the part.

20 . The method of claim 19 , the operation of clamping the mold comprising applying an air pressure ranging from 90 psi to 110 psi to clamp the mold.

21 . The method of claim 19 , the operation of unclamping the mold comprising releasing an air pressure to unclamp the mold.

22 . The method of claim 10 , the operation of molding a part comprising:

clamping a mold;

moving the barrel forward relative to the extrusion screw to open a nozzle to allow the material to flow into the mold;

continuously rotating the extrusion screw to pump the material at the adjusted temperature into the mold;

determining if the mold is filled;

moving the barrel rearward relative to the extrusion screw to shut off the nozzle;

cooling the mold; and

unclamping the mold to release the part.

23 . The method of claim 10 , further comprising filling a hopper with the material to be molded; and cooling the hopper with a coolant prior to the step of switching on one or more heaters to heat a material inside the barrel to the selected barrel temperature.

24 . The method of claim 10 , wherein the material is selected from a group consisting of amorphous thermoplastics, crystalline and semi-crystalline thermoplastics, virgin resins, fiber reinforced plastics, recycled thermoplastics, post-industrial recycled resins, post-consumer recycled resins, mixed and comingled thermoplastic resins, organic resins, organic food compounds, carbohydrate based resins, sugar-based compounds, gelatin, propylene glycol compounds, starch based compounds, and metal injection molding (MIM) feedstocks.