Mark A Hinton

US Patent:

54498775, Sep 12, 1995

Filed:

Dec 29, 1993

Appl. No.:

8/175036

Inventors:

Paul R. Buda - Raleigh NC
Mark A. Hinton - Elgin SC

Assignee:

Square D Company - Palatine IL

International Classification:

B23K 1124

US Classification:

219110

Abstract:

A weld controller utilizing a constant current control employs a stepper program for increasing current boost in predetermined percentage increments or steps following a predetermined stepper current profile to provide compensation for contact tip wear. The weld controller acquires weld power data in the form of current and voltage samples for each step of the stepper program, and computes Volt Amperes or power from this data during an acquisition run through the stepper program. The stepper program specifies a constant current at each step. Associated with each incremental current step, weld power that is required to produce that weld current is determined by the weld controller to generate a characteristic power curve. The power curve will be over the range of currents as specified by the combination of the programmed weld current and the range of current boost as specified by the stepper schedule. The weld controller will build a table of values relating weld current and delivered power or Volt Amperes.

US Patent:

53860969, Jan 31, 1995

Filed:

Dec 23, 1993

Appl. No.:

8/173835

Inventors:

Paul R. Buda - Raleigh NC
Mark A. Hinton - Elgin SC

Assignee:

Square D Company - Palatine IL

International Classification:

B23K 1124

US Classification:

219110

Abstract:

A weld controller employs a stepper program for increasing heat boost in one percent increments or steps to provide compensation for contact tip wear. The weld controller acquires weld current data in the form of current samples for each step to create a characteristic curve or nominal current profile for the stepper program. Subsequent operations of the weld control utilize high and low current limit thresholds that track the nominal current profile. The thresholds can be defined as a fixed offset from the profile or as a percentage of the profile at each step of the stepper program. This allows the use of current limits to be established in close proximity to the nominal weld current at all times, enabling the use of tighter tolerances.