US3873804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Welding helmet with eye piece control
Assignee: Individual
•
Filing: 1973-12-26
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Granted: 1975-03-25
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Expires: 1993-12-26
Abstract
Abstract A protective welding lens assembly is shown, as for use in the eye piece of a welding helmet, utilizing a liquid crystal together with an electrical circuit which applies a suitable electrical potential to the liquid crystal to change the same from a uniform light transmitting condition to a uniform approximately opaque condition of very small light transmission solely in response to approach to the welding electrode close to the workpiece to be welded.
Inventors
- 👤 Mack Gordon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:09
CPC Classifications
A; A61; A61F; A61F9/00; A61F9/04; A61F9/06; A61F9/065; A61F9/067
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
208 words
A protective welding lens assembly for use with an electrical welding machine having an electrical energizing circuit and having a welding electrode connected thereto by an electrical cable, said assembly being planar and fixedly mounted in a welder''s helmet, and comprising a layer of liquid crystal material sandwiched between opposing parallel plates coated over their entire area with unbroken transparent conducting films, said films being pretreated by rubbing the same in parallel lines at right angles to each other whereby to control their polarizing effect upon said liquid crystal material, said plates with the enclosed liquid crystal material being disposed between and parallel to a pair of conventional cross polarizers so arranged that when a suitable electrical potential is established across said conducting films and said liquid crystal layer the lens assembly will change from a uniform light transmitting condition to a uniform high density approximately opaque condition, and means including a low voltage electrical circuit electrically associated with said electrical energizing circuit and responsive solely to approach of said welding electrode to the work to be welded by the wearer of the helmet for applying said suitable electrical potential across said conducting films and said liquid crystal layer in a period of approximately 1/500 of a second.
Claim 2
Dependent Claim
208 words
A protective welding lens assembly for use with an electrical welding machine having an electrical energizing circuit and having a welding electrode connected thereto by an electrical cable, said assembly being planar and fixedly mounted in a welder''s helmet, and comprising a layer of liquid crystal material sandwiched between opposing parallel plates coated over their entire area with unbroken transparent conducting films, said films being pretreated by rubbing the same in parallel lines at right angles to each other whereby to control their polarizing effect upon said liquid crystal material, said plates with the enclosed liquid crystal material being disposed between and parallel to a pair of conventional cross polarizers so arranged that when a suitable electrical potential is established across said conducting films and said liquid crystal layer the lens assembly will change from a uniform light transmitting condition to a uniform high density approximately opaque condition, and means including a low voltage electrical circuit electrically associated with said electrical energizing circuit and responsive solely to approach of said welding electrode to the work to be welded by the wearer of the helmet for applying said suitable electrical potential across said conducting films and said liquid crystal layer in a period of approximately 1/500 of a second.
Claim 3
Dependent Claim
26 words
A welding lens assembly as defined in claim 1, wherein said liquid crystal material is of the nematic type of mesophase with a positive dielectric anisotropism.
Claim 4
Dependent Claim
43 words
A welding lens assembly as defined in claim 2, wherein said last named means includes a switching device responsive to visible light from a welding arc struck between a welding electrode and a workpiece upon approach of said electrode close to a workpiece.
Claim 5
Dependent Claim
36 words
A welding lens assembly as defined in claim 2, wherein said last named means includes a switching device responsive to infra-red rays emitted from an electrode approaching a workpiece prior to the emission of actinic rays.
Claim 6
Dependent Claim
52 words
A welding lens assembly as defined in claim 2, wherein said welding machine utilizes direct current, and said last named means includes a current transformer operatively associated with said electrical cable and a switching device in said electrical circuit responsive to current generated in said transformer when said electrode approaches a workpiece.
Claim 7
Dependent Claim
54 words
A welding lens assembly as defined in claim 2, wherein said welding machine utilizes alternating current and said last named means includes a capacitance type pickup operatively associated with said electrical cable and a switching device in said electrical circuit responsive to change in said capacitance when said electrode is advanced to a workpiece.
Claim 8
Dependent Claim
57 words
A welding lens assembly as defined in claim 2, for use with a welding machine utilizing direct or alternating current, wherein said last named means includes an electromagnetic-responsive ferrite core antenna operatively associated with said electrical cable, and said last named means includes a switching device in said electrical circuit responsive to a signal from said antenna.
Claim 9
Dependent Claim
53 words
A welding lens assembly as defined in claim 2, for use with a welding machine having a high frequency welding current, wherein said last named means includes a detector responsive to high frequency, and said last named means includes a switching device in said electrical circuit responsive to a signal from said detector.
Claim 10
Dependent Claim
55 words
A welding lens assembly as defined in claim 8, including a switching device in circuit with said high frequency detector, said last named switching device responsive to visible light from a welding arc struck between a welding electrode connected with said welding machine and a workpiece upon approach of said electrode close to said workpiece.
Claim 11
Dependent Claim
52 words
A welding lens assembly as defined in clAim 2, wherein said welding machine utilizes alternating current, wherein said last named means includes a voltage transformer operatively associated with said electrical cable and a switching device in said electrical circuit responsive to electrical flow from said transformer when said electrode approaches a workpiece.
Claim 12
Dependent Claim
56 words
A welding lens assembly as defined in claim 10, including a switching device in circuit with said first named switching device, said last named switching device responsive to visible light from a welding arc struck between a welding electrode connected with said welding machine and a workpiece upon approach of said electrode close to said workpiece.
Claim 13
Dependent Claim
30 words
A welding lens assembly as defined in claim 10, responsive to infra-red rays emitted between a welding electrode and a workpiece upon approach of said electrode close to a workpiece.
References Cited (Backward Citations)
US3731986A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |