Electric lamp and discharge devices – Cathode ray tube – Shadow mask – support or shield
Reexamination Certificate
1999-06-22
2001-06-19
Patel, Vip (Department: 2879)
Electric lamp and discharge devices
Cathode ray tube
Shadow mask, support or shield
C313S402000
Reexamination Certificate
active
06249081
ABSTRACT:
TECHNICAL FIELD
This invention relates to cathode ray tubes and more particularly to face panels therefore having article supporting studs retained therein. Still more particularly, it relates to the studs themselves.
BACKGROUND ART
In certain types of cathode ray tubes, particularly those adapted to provide color imagery, it is conventional to position specialized structures, such as grids or apertured shadow masks, in the proximity of the cathodoluminescent screen. These structures generally are supported within the face panel on a plurality of supporting studs embedded in the wall of the face panel. The studs, which are heated for sealing into the wall, are of an alloy having a thermal coefficient of expansion that is compatible with the glass. The usual form of the studs is a hollow body having a head for receiving a support spring and a skirt for insertion into the glass wall of the face panel. In past practice, these studs have been manufactured from an iron alloy comprised of 18 to 26 weight percent chromium and the balance iron (ASTM F256) and, more specifically, an 18 to 20 weight percent chromium-iron alloy (430TiM) stabilized with 0.2 to 0.6 weight percent titanium. Other iron-based alloys that have been used for glass to metal sealing in such face panels have included chromium-free nickel alloys and chromium-nickel-iron alloys such as ASTM F31. These alloys are expensive.
DISCLOSURE OF INVENTION
It is, therefore, an object of the invention to obviate the disadvantages of the prior art.
It is another object of the invention to provide a low cost stud that is suitable for metal sealing in cathode ray tube face panels.
These objects are accomplished, in one aspect of the invention, by providing a cathode ray tube face panel having an upstanding wall therearound with a plurality of article supporting studs retained therein, said studs being formed from an alloy having a chromium content of from about 10 to 16% by weight and the balance iron.
In a preferred embodiment of the invention, the stud has a chromium content of 12 to 14%.
These studs are compatible with the glass of the cathode ray tube face panel and are workable and less expensive than those previously employed.
REFERENCES:
patent: 3379913 (1968-04-01), Gannoe
patent: 4755713 (1988-07-01), Wageaknecht et al.
patent: 4886997 (1989-12-01), Inoue et al.
McNeill William H.
Osram Sylvania Inc.
Patel Vip
LandOfFree
Low chromium ferritic stainless steel studs for cathode ray... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Low chromium ferritic stainless steel studs for cathode ray..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low chromium ferritic stainless steel studs for cathode ray... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455556