US3838244A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical system for automatic arc welding
Assignee: General Dynamics Corp
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Filing: 1971-04-22
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Granted: 1974-09-24
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Expires: 1991-04-22
Abstract
Abstract A process and system for welding of the tungsten inert gas (TIG) type is described. A welding torch is mounted on a mechanism which provides for motion of the torch with respect to the work (a pipe being welded) in three different directions. Movement in each direction is electronically controlled so as to obtain preset magnitudes of oscillation of the torch, both vertically and laterally with respect to the work. The vertical oscillation is provided by following the pulsating arc current in accordance with a preselected control function. In addition, the system and process provides for control of substantially all of the parameters affecting the formation of the weld in order to produce improved weldments.
Inventors
- 👤 P Petrides
- 👤 R Nickerson
- 👤 R Cordeiro
- 👤 J Dodson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:27
CPC Classifications
B; B23; B23K; B23K10/00; B23K10/006; B23K9/00; B23K9/02; B23K9/028; B23K9/0282; B23K9/0286; B23K9/09; B23K9/095; B23K9/12; B23K9/127; B23K9/24; B23K9/28; B23K9/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
319 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for driving said torch with respect to the work in a plurality of different directions at least one of which is along a vertical line between the work and said torch, c. means for providing to said torch welding current having a plurality of different waveforms in one of which the current slopes to a level at which the arc is extinguished, d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving means and providing different ones of said current waveforms in preselected time sequence, said timing and programming means being operative to inhibit said driving means from moving said torch in at least one of said different directions when said waveform with said current slope is provided, e. means for detecting the welding current flowing to said torch for inhibiting the enablement of driving means to drive said torch in said vertical direction until said current exceeds a predetermined level, and f. means responsive to the output of said welding current detection means for providing a short circuit between said torch and the work until said welding current exceeds a predetermined level, wherein said short circuit providing means including a main SCR connected between said torch electrode and a point at substantially the same potential as said work, a first discharge circuit means connected between said torch and said point for triggering said main SCR when the voltage thereacross exceeds a first potential, a second discharge circuit means including at least one secondary SCR connected across said main SCR, and means operated by said weld current detection means for triggering said secondary SCR when said welding current exceeds a predetermined magnitude for applying a potential across said main SCR for cutting off said main SCR.
Claim 2
Dependent Claim
319 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for driving said torch with respect to the work in a plurality of different directions at least one of which is along a vertical line between the work and said torch, c. means for providing to said torch welding current having a plurality of different waveforms in one of which the current slopes to a level at which the arc is extinguished, d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving means and providing different ones of said current waveforms in preselected time sequence, said timing and programming means being operative to inhibit said driving means from moving said torch in at least one of said different directions when said waveform with said current slope is provided, e. means for detecting the welding current flowing to said torch for inhibiting the enablement of driving means to drive said torch in said vertical direction until said current exceeds a predetermined level, and f. means responsive to the output of said welding current detection means for providing a short circuit between said torch and the work until said welding current exceeds a predetermined level, wherein said short circuit providing means including a main SCR connected between said torch electrode and a point at substantially the same potential as said work, a first discharge circuit means connected between said torch and said point for triggering said main SCR when the voltage thereacross exceeds a first potential, a second discharge circuit means including at least one secondary SCR connected across said main SCR, and means operated by said weld current detection means for triggering said secondary SCR when said welding current exceeds a predetermined magnitude for applying a potential across said main SCR for cutting off said main SCR.
Claim 3
Dependent Claim
50 words
The invention as set forth in claim 1 including means connected in said first and second discharge circuit means and responsive to said welding current for preventing operation of said first and second discharge circuit means when welding current above approximately said predetermined magnitude is being supplied to said torch.
Claim 4
Dependent Claim
302 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for driving said torch with respect to the work in a plurality of different directions at least one of which is along a vertical line between the work and said torch, c. means for providing to said torch welding current having a plurality of different waveforms in one of which the current slopes to a level at which the arc is extinguished, and d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving means and providing different ones of said current waveforms in preselected time sequence, said timing and programminG means being operative to inhibit said driving means from moving said torch in at least one of said different directions when said waveform with said current slope is provided, wherein said welding current supplying means includes means for generating welding current connected to said torch, and means for controlling the waveform of said welding current generating means, said welding current control means being connected to said timing and programming means for enabling the generation of said different current waveforms, wherein said welding current control means includes means for generating pulses having selectable rates and durations, current amplitude selection logic means responsive to said pulses for selectively providing outputs on a plurality of different lines, each corresponding to different amplitude levels of said pulses, means including in said amplitude selection logic responsive to said timing and programming means outputs for enabling said logic to provide outputs on selected ones of said lines, and means connected to said lines for applying a control signal to said welding current generating means for generating the selected ones of said pluralities of different waveforms.
Claim 5
Dependent Claim
302 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for driving said torch with respect to the work in a plurality of different directions at least one of which is along a vertical line between the work and said torch, c. means for providing to said torch welding current having a plurality of different waveforms in one of which the current slopes to a level at which the arc is extinguished, and d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving means and providing different ones of said current waveforms in preselected time sequence, said timing and programminG means being operative to inhibit said driving means from moving said torch in at least one of said different directions when said waveform with said current slope is provided, wherein said welding current supplying means includes means for generating welding current connected to said torch, and means for controlling the waveform of said welding current generating means, said welding current control means being connected to said timing and programming means for enabling the generation of said different current waveforms, wherein said welding current control means includes means for generating pulses having selectable rates and durations, current amplitude selection logic means responsive to said pulses for selectively providing outputs on a plurality of different lines, each corresponding to different amplitude levels of said pulses, means including in said amplitude selection logic responsive to said timing and programming means outputs for enabling said logic to provide outputs on selected ones of said lines, and means connected to said lines for applying a control signal to said welding current generating means for generating the selected ones of said pluralities of different waveforms.
Claim 6
Dependent Claim
25 words
The invention as set forth in claim 3 including means connected to each of said lines for independently varying the amplitude of the signal thereon.
Claim 7
Dependent Claim
191 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for providing to said torch welding current having a plurality of different waveforms, c. means for driving said torch with respect to the work, d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving and providing different ones of said current waveforms in preselected time sequence, and, e. welding current control means in said means for providing current, comprising: i. means for generating pulses having selectable rates and durations, ii. current amplitude selection logic means responsive to said pulses for selectively providing outputs on a plurality of lines, each corresponding to different amplitude levels of said generated pulses, iii. means included in said amplitude selection logic means responsive to said timing and programming means outputs for enabling said logic means to provide outputs on selected ones of said lines, and iv. means connected to said lines for applying a control signal to said means for providing current for generating the selected ones of said plurality of different waveforms.
Claim 8
Dependent Claim
191 words
An automatic arc welding system comprising; a. a torch means for providing an arc with which work can be welded, b. means for providing to said torch welding current having a plurality of different waveforms, c. means for driving said torch with respect to the work, d. timing and programming means connected to said driving means and to said welding current providing means for enabling said driving and providing different ones of said current waveforms in preselected time sequence, and, e. welding current control means in said means for providing current, comprising: i. means for generating pulses having selectable rates and durations, ii. current amplitude selection logic means responsive to said pulses for selectively providing outputs on a plurality of lines, each corresponding to different amplitude levels of said generated pulses, iii. means included in said amplitude selection logic means responsive to said timing and programming means outputs for enabling said logic means to provide outputs on selected ones of said lines, and iv. means connected to said lines for applying a control signal to said means for providing current for generating the selected ones of said plurality of different waveforms.
References Cited (Backward Citations)
US2773970A
Cited
US3102948A
Cited
US3133187A
Cited
US3207881A
Cited
US3317811A
Cited
US3233076A
Cited
US3538299A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |