Electric heating – Metal heating – For bonding with pressure
Reexamination Certificate
1999-04-01
2001-10-02
Shaw, Clifford C. (Department: 1725)
Electric heating
Metal heating
For bonding with pressure
C219S119000
Reexamination Certificate
active
06297467
ABSTRACT:
BACKGROUND OF THE INVENTION
Field of the Invention
1. Technical Field
The present invention relates generally to a transducer built into an electrode and, more particularly, to a transducer built into an electrode for real time resistance spot welding monitoring and feedback.
2. Discussion
Welding is a common process for attaching one metal member to another. This process generally involves heating an interface between the items which are to be welded, thereby melting the interface into one joint or weld nugget. Because this process has its application in many different types of manufacturing, such as automobile manufacturing, inspection ensuring that the weld nugget meets certain quality standards is a must. Specifically, it is desirable to inspect the area, size and configuration of the weld nugget and to determine if any defects exist therein. Uninspected welds may result in weld failure after the welded item is sold or distributed to a final user.
Ideally, a weld is inspected either during or shortly after the welding process so that added inspection does not increase weld time, and to allow weld problems to be identified when they occur. Furthermore, non-destructive testing is preferred so that welded parts which pass inspection may still be sold or distributed to the end user.
Visual inspection systems have been employed in the weld environment for this purpose. Specifically, an individual, such as a quality control person, may gage the size of the weld nugget or destructively test a welded item to determine its internal characteristics. However, these methods have several drawbacks. First, because of the bright light and harsh conditions generated by welding, visual inspection of a weld cannot be performed during the welding process. Instead, the welded item must be inspected off line, adding more time and cost to manufacturing. Second, to properly inspect the weld for defects, the internal structure of the weld nugget must be observed. This, in many instances, requires the welded item to be destructively tested, rendering the welded item useless. Besides the increased cost associated with scrapping an item for the purpose of inspection, it is practically impossible to destructively test all items. As such, destructive testing results in a lower number of samples tested and increased cost to manufacturing. The present invention was developed in light of these drawbacks.
SUMMARY OF THE INVENTION
The present invention addresses the aforementioned drawbacks, among others, by providing an electrode assembly for a spot welder which has an ultrasonic probe built therein. In a preferred embodiment of the present invention, a spot welder has a first and second electrode assembly containing first and second ultrasonic probes respectively. During welding, the ultrasonic probe from the first electrode assembly generates a burst of acoustic energy. One portion of this acoustic energy passes through a weld subject and resonates the first ultrasonic probe and another portion is reflected back by the weld subject and is received by the second ultrasonic probe. The ultrasonic probe in the first or second electrode assembly then emits an output signal, representative of the geometry of the weld nugget, to a computer.
Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 3384733 (1968-05-01), Burbank et al.
patent: 3410983 (1968-11-01), Deutsch et al.
patent: 3575044 (1971-04-01), Gibbs et al.
patent: 3739628 (1973-06-01), Saglio
patent: 3868847 (1975-03-01), Gunkel
patent: 3895685 (1975-07-01), Gillette et al.
patent: 3958451 (1976-05-01), Richardson
patent: 3960005 (1976-06-01), Vezina
patent: 4012946 (1977-03-01), Patsey
patent: 4099045 (1978-07-01), Okuda et al.
patent: 4208917 (1980-06-01), Aoyama et al.
patent: 4449029 (1984-05-01), Nied
patent: 4480475 (1984-11-01), Tsao et al.
patent: 4711984 (1987-12-01), Bilge et al.
patent: 4712722 (1987-12-01), Hood et al.
patent: 4918990 (1990-04-01), Fowler et al.
patent: 5060518 (1991-10-01), Aleshin et al.
patent: 5439157 (1995-08-01), Geier et al.
patent: 5474225 (1995-12-01), Geier et al.
patent: 5537875 (1996-07-01), Viehmann et al.
patent: 5920014 (1999-07-01), Waschkies
patent: 6072144 (2000-06-01), Perryman
Gr. Maev Roman
Mann John L.
Ptchelintsev Andrei A.
Calcaterra Mark P.
DaimlerChrysler Corporation
Shaw Clifford C.
LandOfFree
Transducer built into an electrode does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transducer built into an electrode, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transducer built into an electrode will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2559629