Patent USH1083H successfully refreshed from Google Patents.
Patent US3674976A successfully refreshed from Google Patents.
US3674976A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Welding head for producing uniform and repeatable resistance welds
Assignee: PNC Bank NA
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Filing: 1970-11-13
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Granted: 1972-07-04
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Expires: 1990-11-13
Abstract
Abstract In a welding head, the weight of a substantially free-falling body is applied to a welding electrode via a lever, the mechanical advantage introduced by the lever being selected to achieve a predetermined movement of said electrode into a body to be welded during a predetermined time interval, irrespective of the magnitude of the weight, the weight being selected to apply a predetermined weld pressure at the electrode via the mechanical advantage of the lever. Timing operation depends solely on a falling weight and hence is perfectly reproducible for a variety of weld pressures.
Inventors
- 👤 Sheldon S Bitko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:56
CPC Classifications
B; B23; B23K; B23K11/00; B23K11/10; B23K11/11; B23K11/115
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
206 words
A welding head, comprising a support member, a pair of welding electrodes, first and second lever arms disposed at right angles to one another, means pivotally supporting said first and second lever arms at a pivot point such that said first and second lever arms are pivotable together about said pivot point, means securing at least one of said welding electrodes to said first lever arm at a predetermined distance from said pivot point, means for applying a variable torque to said second lever comprising means for receiving a weight of variable amount at variable locations along the length thereof, means for spacing said welding electrodes in contact with said elements to permit at least a portion of the elements to be welded to present a resistive current path between said welding electrodes and such that said elements are urged together by said electrodes with a horizontal force determined by the torque applied by said weight to said second lever arm, supply means for passing a pulse of welding current between said welding electrodes for a specified time interval, said welding current being sufficiently high to soften said elements to be welded and thereby to enable full force of said weight under the influence of gravity.
Claim 2
Dependent Claim
206 words
A welding head, comprising a support member, a pair of welding electrodes, first and second lever arms disposed at right angles to one another, means pivotally supporting said first and second lever arms at a pivot point such that said first and second lever arms are pivotable together about said pivot point, means securing at least one of said welding electrodes to said first lever arm at a predetermined distance from said pivot point, means for applying a variable torque to said second lever comprising means for receiving a weight of variable amount at variable locations along the length thereof, means for spacing said welding electrodes in contact with said elements to permit at least a portion of the elements to be welded to present a resistive current path between said welding electrodes and such that said elements are urged together by said electrodes with a horizontal force determined by the torque applied by said weight to said second lever arm, supply means for passing a pulse of welding current between said welding electrodes for a specified time interval, said welding current being sufficiently high to soften said elements to be welded and thereby to enable full force of said weight under the influence of gravity.
Claim 3
Dependent Claim
85 words
The welding head according to claim 1 wherein the weighting location y on said second lever arm, for a given welding operation, is given by the following expression: where x is said predetermined distance between said at least one welding electrode and said pivot point; d is a desired depth of the weld to be formed; a is the gravitational acceleration constant; and t is the period of time during which said elements to be welded are softened by welding current passed between the electrodes.
Claim 4
Dependent Claim
98 words
The welding head according to claim 1 wherein said supply means comprises a welding current supply having a selectively variable welding current interval selected for a given welding operation in accordance with the following expression: where t is the interval of time during which said elements to be welded are softened in response to said welding current interval, y is the weighting location on said second lever arm, d is the desired depth of weld, a is the gravitational acceleration constant, and x is said predetermined distance between said at least one welding electrode and said pivot point.
Claim 5
Dependent Claim
119 words
The welding head according to claim 1 wherein for a given welding operation the weighting W of said second lever arm is determined by the following expression: W Fx/y where F is the desired forging force to be applied against said elements by said electrodes, x is said predetermined distance between said at least one welding electrode and said pivot point, and y is the weighting location on said second lever arm; and wherein y is determined by the expression: where d is the desired depth of weld, a is the gravitational acceleration constant, and t is the period of time during which the elements to be welded are softened by the welding current passed through said welding electrodes.
Claim 6
Dependent Claim
121 words
In the method of welding a workpiece which includes the steps of urging a pair of spaced welding electrodes against said workpiece to apply a predetermined compressive force thereto by applying a weight thereto via a lever arm; passing a welding current of predetermined duration through said electrodes and said work piece to soften said workpiece and permit penetration of at least one of said electrodes into said workpiece in response to said weight, the improvement comprising adjusting the position of said weight along said lever arm to provide penetration of said workpiece to a desired depth over a period of time in excess of said predetermined duration, and selecting the value of said weight to establish said predetermined compressive force.
Claim 7
Dependent Claim
121 words
In the method of welding a workpiece which includes the steps of urging a pair of spaced welding electrodes against said workpiece to apply a predetermined compressive force thereto by applying a weight thereto via a lever arm; passing a welding current of predetermined duration through said electrodes and said work piece to soften said workpiece and permit penetration of at least one of said electrodes into said workpiece in response to said weight, the improvement comprising adjusting the position of said weight along said lever arm to provide penetration of said workpiece to a desired depth over a period of time in excess of said predetermined duration, and selecting the value of said weight to establish said predetermined compressive force.
References Cited (Backward Citations)
US3303316A
Cited
US3316383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-04 | 1976-01-03 | 1976-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-04 | 1980-01-03 | 1980-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-04 | 1984-01-03 | 1984-07-04 | $7700.00 | Window Closed / Lapsed |