Electric lamp or space discharge component or device manufacturi – Process – With assembly or disassembly
Reexamination Certificate
1999-12-14
2001-08-28
Ramsey, Kenneth J. (Department: 2879)
Electric lamp or space discharge component or device manufacturi
Process
With assembly or disassembly
Reexamination Certificate
active
06280276
ABSTRACT:
This invention relates to a method of fabricating a tension mask type of color picture tube, and particularly to a method of applying pressure to a tension mask frame to obtain a desired tension distribution in the mask when it is attached thereto.
BACKGROUND OF THE INVENTION
A color picture tube includes an electron gun for generating and directing three electron beams to the screen of the tube. The screen is located on the inner surface of a faceplate of the tube and is made up of an array of elements of three different color-emitting phosphors. A color selection electrode, which may be either a shadow mask or a focus mask, is interposed between the gun and the screen to permit each electron beam to strike only the phosphor elements associated with that beam.
One type of color picture tube has a tension mask mounted within a faceplate panel thereof. In order to maintain the tension on the mask, the mask must be attached to a support frame. In making a tension mask-frame assembly, the mask is attached to the frame while the frame is held in a compressed condition. After attachment of the mask to the frame, such as by welding, the frame compression is released, so that the frame springs outwardly to tension the mask. The conventional method for compressing the frame is to press on the frame members with blades shaped to provide the proper frame deflection for the desired mask tension distribution. Slight distortions of the frame, especially in frames made of relatively thin material, can result in undesirable uneven tensioning of the mask. Such undesirable variations in tension arise because of the conventional method reliance on fixed displacement inputs to the frame to provide a tension distribution.
SUMMARY OF THE INVENTION
The present invention provides a method of attaching a tension mask to a frame to achieve desired tensions at a plurality of locations across the mask, wherein the frame has two opposite sides between which the mask is to be attached. In the method, specific forces are applied from each of a plurality of separate actuators at positions, along each of the two opposite sides of the frame, that affect the mask tensions respectively at the plurality of locations across the mask. Each of the actuators is individually controlled to apply a specific force to a frame side that is directly related to the desired mask tension required at a particular mask location. While the specific forces are applied by the actuators, a mask is attached to the two opposite sides of the frame.
REFERENCES:
patent: 3638063 (1972-01-01), Tachikawa et al.
patent: 4333034 (1982-06-01), Ohgoshi et al.
patent: 4745328 (1988-05-01), Strauss
patent: 4950945 (1990-08-01), Fendley et al.
patent: 5111106 (1992-05-01), Kaplan et al.
patent: 5681197 (1997-10-01), Egami et al.
patent: 6106353 (2000-08-01), Kimura et al.
PCT Search Report dated: Mar. 28, 2001.
Bucher Alan Weir
Ragland, Jr. Frank Rowland
Irlbeck Dennis H.
Ramsey Kenneth J.
Thomson Licensing S.A.
Tripoli Joseph S.
LandOfFree
Method of attaching a tension mask to a frame does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of attaching a tension mask to a frame, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of attaching a tension mask to a frame will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2531893