Stud welding apparatus with two-wire control

Claim 2

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid, a solenoid core connected to said stud holding means, a start switch, a welding cable electrically connected to said stud holding means independently of said solenoid coil, welding cycle controls remote from said stud welding tool having means for controlling the supply of power to said coil independently of the length of time said start switch is closed, means for supplying power to said welding cable independently of said solenoid coil to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising only two wires connecting said responsive means to said start switch and said controlling means to said start switch, whereby the same two wires connect said responsive means to said controlling means.

Claim 3

Stud welding apparatus according to claim 1 characterized by said responsive means being electrically connected in parallel with said controlling means.

Claim 4

In stud welding apparatus for welding studs to workpieces by a drawn-arc technique, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a weld cable electrically connected to said stud holding means, and controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising conductor means in said welding tool electrically connecting said solenoid coil and contacts of said start switch, means in said conductor means enabling current to flow through said coil only in one direction and for enabling current to flow through said start switch only in the opposite direction, and only two wires connected between said conductor means and said responsive means, whereby both wires carry the controlling current and the solenoid coil current.

Claim 5

In stud welding apparatus for welding studs to workpieces by a drawn-arc technique, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a weld cable electrically connected to said stud holding means, and controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising conductor means in said welding tool electrically connecting said solenoid coil and contacts of said start switch, means in said conductor means enabling current to flow through said coil only in one direction and for enabling current to flow through said start switch only in the opposite direction, and only two wires connected between said conductor means and said responsive means, whereby both wires carry the controlling current and the solenoid coil current.

Claim 6

Stud welding apparatus according to claim 3 chararcterized by conducting means connecting said responsive means in parallel with said controlling means.

Claim 7

Stud welding apparatus according to claim 3 characterized by two light-emitting diodes electrically connected in opposite directions across said wires and effective to indicate three conditions of said apparatus.

Claim 8

Stud welding apparatus according to claim 3 characterized by a first light-emitting diode electrically connected across said wires in one direction to indicate a condition of said apparatus, a second light-emitting diode electrically connected in the opposite direction across said wires to indicate a second condition of said apparatus, and said diodes being effective to both light to indicate a third condition of said apparatus.

Claim 9

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding the studs, an electrical solenoid coil connected to said stud holding means, a start switch, a weld cable electrically connected to said stud holding means, and a welding cycle control circuit remote from said stud welding tool having means for controlling the supply of power to said solenoid coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece, when spaced apart, and means responsive to the closing of said start switch to initiate a welding cycle, the improvement comprising conducting means connecting said responsive means in parallel with said controlling means, conductor means in said welding tool electrically connecting said start switch in parallel with said solenoid coil, diode means in said conductor means for enabling current to flow through said coil only in one direction and for enabling current to flow through said start switch only in the opposite direction, and only two wires connection said conductor means and said responsive means, whereby both wires carry the controlling current and the solenoid coil current.

Claim 10

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding the studs, an electrical solenoid coil connected to said stud holding means, a start switch, a weld cable electrically connected to said stud holding means, and a welding cycle control circuit remote from said stud welding tool having means for controlling the supply of power to said solenoid coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece, when spaced apart, and means responsive to the closing of said start switch to initiate a welding cycle, the improvement comprising conducting means connecting said responsive means in parallel with said controlling means, conductor means in said welding tool electrically connecting said start switch in parallel with said solenoid coil, diode means in said conductor means for enabling current to flow through said coil only in one direction and for enabling current to flow through said start switch only in the opposite direction, and only two wires connection said conductor means and said responsive means, whereby both wires carry the controlling current and the solenoid coil current.

Claim 11

Apparatus according to claim 7 characterized by a power source being connected in series with said responsive means across said two wires.

Claim 12

Apparatus according to claim 7 characterized by said responsive means comprising an optical-coupled silion-controlled rectifier.

Claim 13

Stud welding apparatus according to claim 7 characterized by said responsive means comprising a light-emitting diode, and a unijunction transistor in series with said diode to cause it to be energized when said unijunction transistor is turned on.

Claim 14

Apparatus according to claim 7 characterized by said responsive means comprising a low current requirement relaying circuit.

Claim 15

Apparatus according to claim 7 characterized by a first light-emitting diode electrically connected across said wires in one direction to indicate that the wires are properly connected, a second light-emitting diode electrically connected across said wires in the opposite direction to indicate that the wires are improperly connected, both of said diodes being lighted when there is a short in the welding circuitry.

Claim 16

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a welding cable electrically connected to said stud holding means, welding cycle controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising only two wires connecting said responsive means to said start switch and said controlling means to said start switch, whereby the same two wires connect said responsive means to said controlling means, and two light-emitting diodes electrically connected in opposite directions across said wires to indicate three conditions of said apparatus.

Claim 17

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a welding cable electrically connected to said stud holding means, welding cycle controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising only two wires connecting said responsive means to said start switch and said controlling means to said start switch, whereby the same two wires connect said responsive means to said controlling means, and two light-emitting diodes electrically connected in opposite directions across said wires to indicate three conditions of said apparatus.

Claim 18

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a welding cable electrically connected to said stud holding means, welding cycle controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising only two wires connecting said responsive means to said start switch and said controlling means to said start switch, whereby the same two wires connect said responsive means to said controlling means, a light-emitting diode connected in one direction across said wires to indicate a condition of said apparatus, and a second light-emitting diode connected in an opposite direction across said wires to indicate another condition of said apparatus, said light-emitting diodes being effective to both light to indicate a third condition of said apparatus.

Claim 19

In stud welding apparatus for welding studs to workpieces, said apparatus comprising a welding tool having means for holding a stud, an electrical solenoid coil, a solenoid core connected to said stud holding means, a start switch, a welding cable electrically connected to said stud holding means, welding cycle controls remote from said stud welding tool having means for controlling the supply of power to said coil, means for supplying power to said welding cable to establish an arc between the stud and the workpiece when spaced apart, and means responsive to the closing of said start switch to cause said controlling means to initiate a welding cycle, the improvement comprising only two wires connecting said responsive means to said start switch and said controlling means to said start switch, whereby the same two wires connect said responsive means to said controlling means, a light-emitting diode connected in one direction across said wires to indicate a condition of said apparatus, and a second light-emitting diode connected in an opposite direction across said wires to indicate another condition of said apparatus, said light-emitting diodes being effective to both light to indicate a third condition of said apparatus.