Wire feeder with non-linear speed control

Abstract

A welding machine with a wire feeder and a controller is disclosed. The wire feeder includes a wire feed motor with a motor speed input. The controller is coupled to the motor speed control input. A user selectable wire feed speed input is also connected to the controller. The controller has an input circuit coupled with a non-linear stage such that the relationship between the user selectable wire feed speed input and the actual wire feed speed is not linear. The selectable input may be a potentiometer mounted on a front panel as the user selectable wire feed speed input. The non-linearity may be continuous or two discrete gains.

Description

FIELD OF THE INVENTION [0001] The application relates generally to electrode wire feeders used in welding, and, more particularly, to a wire feed speed controller for wire feeders used in welding. BACKGROUND OF THE INVENTION [0002] Many welding applications such as MIG (metal inert gas) or GMAW (gas metal arc welding) utilize a wire feeder to provide filler metal to the weld. Generally, the wire feeder will provide wire at a nominally constant speed (typically given in inches per minute). Wire feed speed controllers control the speed at which the wire is fed to the arc. [0003] A typical prior art wire feeder incudes a motor that pulls wire from a reel and, feeds the wire to the weld arc. The motor is controlled by a wire feed controller that may be a stand alone controller or maybe part of a controller that controls other aspects of the welding process. The wire feed controller controls the speed of the wire feeder and typically includes a potentiometer on a front panel of the contr...

AI Technical Summary

Benefits of technology

[0015] A first aspect of the invention is a wire feeder that feeds wire to a weld at a controllable rate. The wire feeder includes a wire feed motor with a motor speed input. A controller is coupled to the motor speed control input. A user selectable

Problems solved by technology

However, they have a significant drawback.

However, when welding, the speed selection at the faster end of wire feed speed range (heavier gauge material) need not be as precise as the speed selection at the slower end of the wire feed speed range.

However, when operating at 50 inches per minute, being off by 5 or 10 inches per minute may be very significant and can confuse the operator since 175 inches / minute is available on both toggle switch positions.

However, this requires an additional control switch.

However, this sort of design does not allow the wire feed speed to be displayed in inches per minute on the selector knob.

Additionally, this does not allow the user to effectively access all wire feeds speeds over the entire range, without toggling a switch.

This controller is complex and expensive and has tow adjustment knobs: arc power and arc length.

However, this prior art did not allow independent control of the wire feed speed by a single knob.

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