Patent US4449030A successfully refreshed from Google Patents.
US4449030A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for sensing the distance between an object of electrically conductive material and a reference point
Assignee: Individual
•
Filing: 1982-06-25
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Granted: 1984-05-15
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Expires: 2002-06-25
Abstract
Abstract An apparatus for sensing the distance between an object of electrically conductive material and a reference point has an electrode, the tip of which constitutes the reference point. The electrode is connected via a supply line to a high voltage source adapted to generate high voltage pulses to provide an arc between the electrode tip and the object. The apparatus also has an air-cored measuring coil disposed around the supply line for sensing the electric field about the supply line and transmitting to a measuring signal sensing circuit a measuring signal proportional to the electric field. The measuring signal sensing circuit preferably comprises a comparator unit adapted to compare the measuring signal with a signal corresponding to a predetermined distance between the object and the electrode point.
Inventors
- 👤 Sven G. R. Blomdahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:08
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/12; G01D5/14; G01B; G01B7/00; G01B7/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
137 words
An apparatus for sensing the distance between a workpiece of electrically conductive material and a reference point, the apparatus comprising: a welding gun for forming a seam on the workpiece, an electrode rigidly connected to the welding gun, electrically insulated from the welding gun and having a tip forming the reference point, supply line means for connecting said electrode to a high voltage source and generating high voltage pulses thereby generating an arc between the electrode tip and the workpiece, measuring means for sensing the electric field around the supply line means and for generating a measuring signal corresponding to the electric field, a measuring signal sensing circuit for determining the distance between the workpiece and reference point based upon the measuring signal, and transmitting means for connecting the measuring means to the measuring signal sensing circuit.
Claim 2
Independent Claim
137 words
An apparatus for sensing the distance between a workpiece of electrically conductive material and a reference point, the apparatus comprising: a welding gun for forming a seam on the workpiece, an electrode rigidly connected to the welding gun, electrically insulated from the welding gun and having a tip forming the reference point, supply line means for connecting said electrode to a high voltage source and generating high voltage pulses thereby generating an arc between the electrode tip and the workpiece, measuring means for sensing the electric field around the supply line means and for generating a measuring signal corresponding to the electric field, a measuring signal sensing circuit for determining the distance between the workpiece and reference point based upon the measuring signal, and transmitting means for connecting the measuring means to the measuring signal sensing circuit.
Claim 3
Dependent Claim
16 words
An apparatus as claimed in claim 1, wherein said measuring means is an air-cored measuring coil.
Claim 4
Dependent Claim
25 words
An apparatus as claimed in claim 2, wherein said measuring coil has one free end and another end connected to the measuring signal sensing circuit.
Claim 5
Dependent Claim
18 words
An apparatus as claimed in claim 2, wherein said measuring coil is disposed around the supply line means.
Claim 6
Dependent Claim
40 words
An apparatus as claimed in claim 1 2, 3 or 4, wherein the measuring signal sensing circuit comprises comparator means for comparing the measuring signal to a signal corresponding to a predetermined distance between said object and said electrode tip.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-15 | 1987-11-14 | 1988-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-15 | 1991-11-14 | 1992-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-15 | 1995-11-14 | 1996-05-15 | $7700.00 | Window Closed / Lapsed |