Closed loop interactive controller

An apparatus comprising:

• (a) multiple zones, each zone having at least one chiller and at least one temperature sensor outputting a temperature indicating signal;
• (b) a source providing a cooling medium to the chillers;
• and
• (c) a controller for controlling the temperature of at least some of the zones, the controller comprising:
• (i) a data-receiving processor for receiving the temperature indicating signal from each sensor;
• and
• (ii) a separate control processor for receiving data from the data-receiving processor and for controlling the amount of chilling medium provided to the chillers.

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;
• and
• (c) 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
• (iv) an output signaler for regulating the percentage of complete current cycles provided to the heater for each zone.

An injection mold apparatus comprising:

• (a) a mold having multiple injection zones, each zone having at least one heater and at least one temperature sensor, each sensor outputting a temperature indicating signal;
• (b) a power source providing current to the heaters;
• and
• (c) a controller controlling the temperature of the zones, the controller comprising:
• (i) a first printed circuit board comprising a switch for each heater for limiting the amount of current provided to the respective heater;
• and
• (ii) a second printed circuit board controlling the switches.

A system for controlling an operational parameter of a mold within a selected range, the mold having multiple zones, the system comprising:

• (a) at least one sensor for each zone, each sensor generating an analog signal representative of an operational parameter of the zone;
• (b) at least one device for altering the operational parameters;
• (c) a detector detecting the operating state of the device and generating an analog signal representative of the operating state of the device;
• and
• (d) a controller for processing the analog signals comprising:
• (i) a first processor for digitizing the analog signals and calculating the operational parameter and the RMS operating state for each device;
• and
• (ii) a second processor responsive to the calculated parameters, the second processor performing a PID calculation for determining the amount, if any, the operational parameter for each zone needs to be modified to be within a selected range, the PID calculation providing a range of limits for modifying the amount the operating state of each device is to be modified;
• whereby the controller modifies the operational parameter of each zone within the range of limits.

An apparatus for controlling an operational parameter of a molding process within a selected range, the apparatus comprising:

• (a) a source of AC power generating cycles of an AC wave form;
• (b) a plurality of mold injection zones, each zone having an operational parameter that is power dependent;
• (c) at least one sensor for sensing the operational parameter at each zone and generating analog signals;
• and
• (d) a controller comprising:
• (i) a detector for receiving the analog signals;
• (ii) a first processor for digitizing the analog signals;
• (iii) a power driver for triggering the source of AC power;
• and
• (iv) a second processor for performing a PID calculation for determining the power requirements for each zone, and regulating the power driver to control the number of complete cycles of the AC wave form during which power is supplied to each zone, the second processor comparing the digitized signal against the selected range to calculate the percent number of total AC cycles required to maintain the operational parameter within the selected range.

An apparatus with a controlled heated zone, the zone having a heater, the zone being maintained within a target temperature range, and a temperature sensor associated with the zone, the apparatus comprising:

• (a) an AC power supply that generates an AC wave form;
• (b) a first controller for controlling the temperature of the zone by regulating the percent number of total AC cycles up to a predetermined number of cycles of the AC wave form during which power is supplied to the heater, thereby controlling the amount of AC current received by the heater;
• and
• (c) a second controller for comparing the actual temperature of the zone with the target temperature range to calculate the percent number of total AC cycles required to maintain the target temperature range, the controller determining any difference between the required percent number of AC cycles against the actual number of AC cycles delivered, and accordingly adjusting the actual number of AC cycles supplied to the heater.

A method for controlling the temperature of a zone of a molding apparatus, the zone having an electrical heater powered by electrical current, the method comprising:

• (a) in a duty cycle, sensing the current provided to the heater and providing an analog output signal multiple times;
• (b) digitizing the analog output signals to digital values, there being multiple current values digitized during the duty cycle;
• (c) splitting each digitized value into a higher, H, and a lower, L, bit number, each bit number having N bits, N being an integer;
• (d) determining the sum of squares of the digitized current values by calculating:
• SUM(L×L)+SUM(L×H)×2×2×2N+SUM (H×H)×22N;
• and
• (e) adjusting the amount of current provided to the heater in response to the calculated sum of squares.

A method for controlling the operation of an apparatus having a plurality of operating zones, each zone being equipped with a heater, the method comprising:

• (a) providing AC power to the heaters, the AC power having an AC wave form having a zero cross-over;
• (b) sensing the operational parameter at each zone and generating an analog signal representative of each operational parameter;
• (c) digitizing the analog signals;
• (d) performing a PID calculation on the digitized signals to determine the power requirements for each of the zones, the PID calculations including an integral error limitation restricting the calculated power determination to predetermined limits;
• (e) monitoring the cycles of the AC wave form;
• and
• (f) detecting the zero cross-over point, and applying the calculated power to each heater, beginning and ending at zero cross-over.

A method of controlling the operation of a mold having a plurality of zones, each zone having a target temperature and equipped with at least one heater, the method comprising:

• (a) providing AC power in an AC cycle wave form;
• (b) measuring the temperature at each zone;
• (c) determining the sum integral error between each measured temperature and the corresponding target temperature;
• (d) if there is an error, determining the percent number of total AC cycles required to restore each zone to its target temperature;
• (e) providing an accumulator rate function having a predetermined N bit accumulated limit within a processor;
• (f) counting the cycles of the AC wave form to determine the percent number of total AC cycles required to maintain the target temperature;
• and
• (g) energizing the AC power source for each zone when the percent number of total AC cycles meets the requirements of step (d).

A method for controlling the operation of an apparatus having a plurality of operating zones equipped with heaters, the method comprising:

• (a) providing a source of AC power to the heaters, the AC power having an AC wave form with a zero cross-over;
• (b) detecting at least one operational parameter for each operating zone, the operational parameter being power dependent;
• (c) storing the detected operational parameter;
• (d) sensing the temperature at each zone and generating an analog signal representative of the level of temperature;
• (e) digitizing the analog signals and measuring the digitized signals;
• (f) performing a PID calculation on the measured digitized signals to calculate the power requirements for each of the zones, the PID calculation including an integral error limitation restricting the calculated power requirements to predetermined limits;
• (g) comparing the determined power requirements and the stored operational parameter to calculate the number of complete cycles of the AC wave form required;
• and
• (h) detecting the zero cross-over point and applying the calculated number of complete cycles to the AC power source.

A method for starting up an apparatus having a plurality of heaters, each heater having a heat-up time equal to the amount of time required to heat up the adjacent portion of the apparatus to a start-up temperature with the heater on substantially full power, and including at least two heaters having different heat-up times, the method comprising the steps of:

• (a) comparing the heat-up times of the heaters to identify a longest heat-up time;
• (b) determining for each heater the amount of heat-up power required for each heater to heat up the respective adjacent portion of the apparatus to the start-up temperature in the heat-up time;
• and
• (c) applying to each heater simultaneously the heat-up power, wherein all portions of the apparatus reach their target temperature at substantially the same time.

An injection mold comprising:

• (a) multiple 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 processor is on a printed circuit board and the switches are on a separate printed circuit board.

A system for controlling the operation of an apparatus having a plurality of operating zones, the system comprising:

• (a) at each zone, at least one operating element and a detector generating an analog operating signal representative of the operating state of the operating element;
• (b) an input for each operating element to vary an operational parameter of each zone;
• (c) a sensor for sensing the operational parameter at each zone and generating a corresponding analog sensing signal;
• and
• (d) a controller comprising:
• (i) a first processor for digitizing the signals and determining from the signals the operating state of the operating element and the operational parameter of each zone;
• and
• (ii) a second processor for performing a PID calculation for each zone based on the operating state and the operational parameter of each zone to determine the amount of input for each operating element to maintain the operational parameter of each zone within a selected range, wherein the second processor limits the maximum amount of input determined by the PID calculation to prevent damage to the apparatus and operating elements.

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
• (e) 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 zero crossing detector to provide only complete AC cycles to the heaters;
• whereby each station is maintained within the selected range of operating temperatures.

A system comprising:

• (a) a hot runner injection mold;
• (b) a plurality of heaters for the mold, each heater having a heat-up time equal to the amount of time required to heat up the adjacent portion of the mold to a start-up temperature with the heater on substantially full power, wherein at least two heaters have different heat-up times, and one of the heaters has a longest heat-up time;
• (c) a power source for applying current to the heaters;
• and
• (d) a processor for controlling the power source so that each heater simultaneously receives the amount of heat-up power required for each heater to heat up a respective adjacent portion of the mold to its start-up temperature in the heat-up time, so that all portions of the mold reach their respective start-up temperature during start-up at substantially the same time.

An injection mold apparatus comprising:

• (a) a mold having multiple stations, each station having at least one heater and at least one temperature sensor outputting a temperature indicating signal;
• (b) a power source providing power to the heaters;
• and
• (c) a controller within a housing, the controller controlling the temperature of at least some of the stations and receiving temperature indicating signals from each sensor and controlling the amount of power provided to the heaters in response to the received temperature indicating signals, wherein the housing is mounted on the mold.

A mold apparatus comprising:

• (a) a mold having multiple stations, each station having at least one cooling path and at least one temperature sensor outputting a temperature indicating signal;
• (b) a source of chilling fluid for the chilling path;
• and
• (c) a controller within a housing, the controller controlling the temperature of at least some of the stations and receiving temperature indicating signals from each sensor and controlling the temperature of chilling fluid provided to the chilling path in response to the received temperature indicating signals, wherein the housing is mounted on the mold.

An injection mold apparatus comprising:

• (a) a mold having multiple injection stations, each station having a mold cavity formed by a male mold portion and a female mold portion with a parting line therebetween;
• (b) a sensor for detecting the spacing at the parting line;
• (c) a pressure system for maintaining the parting line closed when injecting plastic into the mold cavity;
• and
• (d) a controller for controlling the pressure provided by the pressure system in response to signals from the detector for automatically maintaining the parting line closed during injection of material into the mold cavity.

A method for controlling the temperature of an apparatus, the apparatus having multiple zones, each zone having at least one heater, the apparatus having a power source for providing power to the heaters, and the method comprising:

• (a) sensing the temperature of each zone with the sensor providing a temperature indicating signal;
• (b) receiving the temperature indicating signal in a data-receiving processor;
• (c) outputting the received data from the data-receiving processor;
• (d) receiving output from the data-receiving processor with a separate control processor, and determining the amount of power provided to the heaters with the control processor;
• and
• (e) outputting from the control processor signals to the power source for controlling the amount of power to the heaters.

A method for controlling the operation of an apparatus having a plurality of operating zones by controlling an operational parameter of each zone within a selected range, each zone having an operating element whose operation affects the operating parameter, the method comprising:

• (a) generating analog signals representative of the operating parameter of each zone and the operating state of each operating element;
• (b) in a first processor, digitizing the signals and determining from the signals the operating state of the operating element and the operating parameter of each zone;
• and
• (c) in a second processor, performing a PID calculation for each zone based on the operating state and the operating parameter to determine the amount of input for each operating element to maintain the operating parameter of each zone within the selected range, wherein the PID calculation is limited within a range to prevent too much input to the operating elements.