Abstract: An inverter-type resistance welding machine includes a keyboard for inputting desired welding current command data corresponding to commanded values, a display unit for displaying, in the form of a numerical table or graph, the welding current command pattern data inputted by the keyboard, a memory for storing a plurality of the welding current command patterns set by the keyboard and from which these patterns are read out in response to a selection command from the keyboard to serve as a control command of the inverter, and acceptability decision means which successively accepts detected welding current at the time of welding for making a comparison with the reference welding current command pattern over a full range of values, checking correlation between the detected welding current and the reference welding current command pattern and determining whether the detected welding current lies within a predetermined tolerance.

Abstract: Items constituting a resistance welding schedule are set to desired numerical values by pressing three kinds of keys, namely a shift key for designating one item after another, and increment and decrement keys for setting or changing a numerical value corresponding to each designated item. Each item is displayed in an individual display section of a display unit, with the display sections being made to blink sequentially as each corresponding item is designated. The numerical values are displayed directly item by item and are set sequentially as the respective items of the schedule are designated.