Welding control

A method of delivering electrical energy to a welding head by welding apparatus that includes a voltage storage device for delivering output energy to the weld head and a charging circuit for establishing a stored voltage in the storage device, said method comprising the steps of:

• empirically determining a nominal voltage in said storage device and target energy delivered to a weld site upon making an acceptable weld with said welding apparatus,
• charging said storage device to said nominal voltage,
• delivering energy from said storage device to the weld head to make a first subsequent weld,
• measuring energy delivered to the weld head during said first subsequent weld, and
• controlling energy delivered to the weld head for making a second subsequent weld in accordance with the magnitude of said measured energy.

Welding apparatus comprising:

• a weld head,
• voltage storage means for delivering electrical energy to said weld head,
• charging means for charging said storage device,
• means for sensing weld energy delivered to said weld head during a weld, and
• means responsive to said means for sensing for controlling said charging means in accordance with sensed weld energy delivered to the weld head from the storage device during a previous weld.

Welding apparatus comprising:

• a weld head,
• a capacitor storage bank for storing a voltage and delivering weld energy to said weld head,
• charging circuit means for charging the storage bank,
• means for establishing a set point voltage,
• comparison means for comparing the voltage in said storage bank with said set point voltage.
• means responsive to said comparison means for shutting down said charging means, and
• sensing means for generating a sensed energy signal indicative of energy delivered to the weld head during a first weld, compensation means responsive to said sensed energy signal for determining a modified set point voltage for use in making a subsequent weld.