Patent US4419562A successfully refreshed from Google Patents.
US4419562A
Expired / Lapsed
US
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Nondestructive real-time method for monitoring the quality of a weld
Assignee: AT&T Inc
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Filing: 1982-01-19
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Granted: 1983-12-06
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Expires: 2002-01-19
Abstract
Abstract Herein disclosed is a noncontact, nondestructive method for monitoring the quality of a high energy weld, e.g., laser beam weld. In accordance with the proposed method, an acoustic sensor (32) is positioned at a distance from the welding zone (34) and picks up airborne acoustic emission signals (33) associated with the laser welding process. These acoustic signals, propagating through the air space between the welding zone (34) and the sensor (32), are detected and analyzed (36,37) to determine the quality of the weld (FIG. 3).
Inventors
- 👤 Min-Chung Jon
- 👤 Vito Palazzo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:49
CPC Classifications
B; B23; B23K; B23K15/00; B23K15/0013; B23K26/00; B23K26/02; B23K26/03; B23K37/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
81 words
Method for monitoring the quality of a weld on a workpiece comprising the steps of: positioning a high frequency wideband acoustic emission sensor in noncontact spaced relation with the workpiece and in noncontact spaced relation with the weld site on said workpiece; detecting at said acoustic emission sensor airborne shock wave signals propagating away from the weld site and having a frequency above 100 KHz; and analyzing the detected high frequency acoustic emission signals thereby determining the quality of the weld.
Claim 2
Dependent Claim
81 words
Method for monitoring the quality of a weld on a workpiece comprising the steps of: positioning a high frequency wideband acoustic emission sensor in noncontact spaced relation with the workpiece and in noncontact spaced relation with the weld site on said workpiece; detecting at said acoustic emission sensor airborne shock wave signals propagating away from the weld site and having a frequency above 100 KHz; and analyzing the detected high frequency acoustic emission signals thereby determining the quality of the weld.
Claim 3
Dependent Claim
98 words
Method for monitoring the quality of a weld on a workpiece comprising the steps of: directing a high energy welding beam toward a weld site on the workpiece thereby forming a plume at said weld site; positioning a high frequency wideband acoustic emission sensor in noncontact spaced relation with the workpiece and in noncontact spaced relation with the weld site; detecting at said acoustic emission sensor airborne shock wave signals propagating away from the plume and having a frequency above 100 KHz; and analyzing the detected high frequency acoustic emission signals thereby determining the quality of the weld.
Claim 4
Dependent Claim
98 words
Method for monitoring the quality of a weld on a workpiece comprising the steps of: directing a high energy welding beam toward a weld site on the workpiece thereby forming a plume at said weld site; positioning a high frequency wideband acoustic emission sensor in noncontact spaced relation with the workpiece and in noncontact spaced relation with the weld site; detecting at said acoustic emission sensor airborne shock wave signals propagating away from the plume and having a frequency above 100 KHz; and analyzing the detected high frequency acoustic emission signals thereby determining the quality of the weld.
Claim 5
Dependent Claim
48 words
Method for monitoring the quality of a weld according to claims 1 or 2, wherein the positioning step comprises the step of: attaching said high frequency acoustic emission sensor to the surface of a metal plate; and positioning said metal plate at a predetermined distance from said workpiece.
Claim 6
Dependent Claim
25 words
Method for monitoring the quality of a weld according to claim 3, wherein said metal plate is positioned between said workpiece and a welding source.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-05 | 1987-06-06 | 1987-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-05 | 1991-06-06 | 1991-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-05 | 1995-06-06 | 1995-12-06 | $7700.00 | Window Closed / Lapsed |