Closed loop interactive controller

An apparatus comprising:

• (a) multiple heated zones, each zone having a target temperature and
• (i) a temperature sensor providing a temperature indicating signal;
• and
• (ii) a heater;
• (b) a power source providing AC current to each heater;
• (c) a detector detecting the amount of current provided to each heater;
• and
• (d) a controller comprising:
• (i) a first processor for receiving the temperature indicating signals;
• (ii) memory for storing the target temperature for each zone;
• (iii) a separate second processor for comparing the actual temperature of each zone against its target temperature and for comparing the detected heater current with an alarm threshold;
• and
• (iv) an output signaler for regulating the percentage of complete current cycles provided to the heater for each zone, the output signaler being responsive to the comparison of heater current with the alarm threshold for detecting an alarm condition when any of the heater currents exceeds the alarm threshold.

An injection mold comprising:

• (a) at least 48 injection stations, each station having at least one heater and at least one temperature sensor, each sensor providing a temperature indicating signal;
• (b) a source of current for the heaters;
• (c) a controller for controlling the temperature of the station, the controller comprising at least one processor for receiving the temperature indicating signals from the sensors, and an on/off switch for each heater controlling the amount of power going to each heater, the switches being controlled by the processor,
• wherein the at least one processor is on a printed circuit board and the switches are on a separate printed circuit board, the temperature signals from up to at least 48 of the injection stations being received by a single processor at a rate of not less than one temperature indicating signal from each temperature sensor per second.

A hot resin injection mold apparatus, the mold having at least forty-eight stations and at least one heater for each station, the apparatus comprising:

• (a) at least one temperature sensor in each station, each sensor outputting a temperature indicating signal;
• (b) an AC power source generating cycles of an AC wave form providing power to the heaters;
• (c) a power driver comprising:
• (i) an on/off switch for controlling the power to each heater;
• (ii) a transformer for measuring the current to each heater;
• and
• (iii) a zero crossing detector for triggering the on/off switch;
• (d) a first processor for receiving the temperature indicating signals comprising:
• (i) an AD converter for digitizing the temperature indicating signals;
• and
• (ii) a first microprocessor for computing the RMS of the measured current values and computing the average of the temperature indicating signals;
• and
• (c) a second processor comprising:
• (i) data memory for storing a selected range for the temperature in each zone;
• (ii) a second microprocessor for performing a PID calculation of the amount of power required to maintain the temperature of each zone within a selected range based on the values computed by the first microprocessor;
• and
• (iii) a zero crossing interrupter for sensing the zero cross-over of the AC wave form and outputting an interrupter signal for signaling the power driver to provide only complete AC cycles to the heaters;
• whereby each station is maintained within the selected range of operating temperatures.