US4330700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasmaburner with contact protection
Assignee: Mansfeld Kombinat Wilhelm Pieck VEB
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Filing: 1980-03-25
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Granted: 1982-05-18
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Expires: 2000-03-25
Abstract
Abstract There is disclosed a plasma burner which has contact protection for protecting the operator against impermissibly high voltage and the burner head itself against destruction. The plasma burner comprises a burner shaft, a nozzle and a nozzle cap surrounding the nozzle, with cooling water flowing between them, a cathode disposed coaxially in the nozzle, a fault current protective circuit and a voltage indicator, disposed over the nozzle cap and insulated therefrom by an air gap is an electrically conductive protective cap.
Inventors
- 👤 Peter Jagieniak
- 👤 Hans Koerdt
- 👤 Jochen Bohme
- 👤 Dieter Odrich
- 👤 Rudolf Pochert
- 👤 Peter Wiese
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:51
CPC Classifications
B; B23; B23K; B23K10/00; B23K10/006
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
142 words
A plasma burner with a contact protection device comprising; a nozzle having concentrically therein, a cathode; a nozzle cap around said nozzle with a space therebetween for cooling water flow; an electrically conductive protective cap around said nozzle cap electrically spaced therefrom by an air space, said protective cap electrically connected to a fault clearing circuit; a voltage indicator connected between a workpiece and said nozzle which functions as a switching device supervising the voltage potentials therebetween; wherein said electrically conductive protective cap is fastened electrically insulated on the shaft of the plasma burner by at least two contact pieces, each of which is connected by a line to the protective fault clearing circuit connection and, in said circuit, a resistor in series to said voltage indicator, at least one capacitor having a diode in series is in parallel to said resistor.
Claim 2
Dependent Claim
142 words
A plasma burner with a contact protection device comprising; a nozzle having concentrically therein, a cathode; a nozzle cap around said nozzle with a space therebetween for cooling water flow; an electrically conductive protective cap around said nozzle cap electrically spaced therefrom by an air space, said protective cap electrically connected to a fault clearing circuit; a voltage indicator connected between a workpiece and said nozzle which functions as a switching device supervising the voltage potentials therebetween; wherein said electrically conductive protective cap is fastened electrically insulated on the shaft of the plasma burner by at least two contact pieces, each of which is connected by a line to the protective fault clearing circuit connection and, in said circuit, a resistor in series to said voltage indicator, at least one capacitor having a diode in series is in parallel to said resistor.
Claim 3
Dependent Claim
15 words
A plasma burner according to claim 1, wherein the protective cap is provided with apertures.
Claim 4
Dependent Claim
18 words
A plasma burner according to claims 1 or 2, wherein the nozzle slightly protrudes from the protective cap.
Claim 5
Dependent Claim
25 words
A plasma burner according to claim 3, wherein the protective cap is fastened to the contact pieces by means of screw threads or resilient cams.
Claim 6
Dependent Claim
21 words
A plasma burner according to claim 4, wherein the voltage indicator is a semiconductor circuit, semiconductor relay, or an electromechanical relay.
References Cited (Backward Citations)
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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) | 1985-05-17 | 1985-11-16 | 1986-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-17 | 1989-11-16 | 1990-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-17 | 1993-11-16 | 1994-05-18 | $7700.00 | Window Closed / Lapsed |