Override control apparatus and method for parameter adjustment of digitally based welding process programmers

Apparatus for controlling a welding control parameter for a welder during a welding process comprising:

• storage means for storing program data representative of:
• a length of a time interval (T) over which welding is to occur,
• an initial value of power (X0) to be supplied to a welding head at the beginning of said time interval, and
• a target value of power (X1) to be supplied to a welding at the termination of said time interval;
• manually actuable input means for changing said target value (X1) during said time interval;
• calculating means for repetitively and frequently calculating, during said time interval, the instantaneous value of power X(t) to be supplied to a welding head according to the equation:
• X(t+dt)=(X1-X(t))t/(T-t)+X(t) indicative of X(t);
• and weld power supply means responsive to the output value X(t) of said calculating means for supplying power to a weld head given by the value X(t), whereby the amount of power supplied to the welding head is calculated repetitively and frequently and whereby the adjustments for the amount of power supplied to the welding head can be made in real time during the welding interval.

A method of controlling a welding parameter during a welding process comprising the steps of:

• providing a programmer with data of:
• a time interval (T) representative of the length of a welding process interval,
• an initial value of power (X0) to be supplied to a welding head at the beginning of said time interval (T) yet to be commenced, and
• a target value of power (X1) to be supplied to a welding head at the termination of said time interval (T) yet to be commenced;
• providing said programmer with data representing desired changes to said target value (X1) during the time interval;
• repetitively and frequently calculating during said time interval, the instantaneous value of power to be supplied to a welding head according to the equation:
• X(t)=(X1-X0)t/T+X0;
• providing power to a welding head during said interval in an amount given by the value X(t), whereby the amount of power supplied to the welding head is calculated repetitively and frequently and whereby adjustments can be made to the amount of power supplied to the welding head during the actual welding interval.