Method of assembling a shadow mask and an apparatus for carrying out the same

A method of assembling an electron beam selection mask formed of a mask sheet for a color cathode ray tube, comprising the steps of:

• providing a frame formed by a pair of spaced apart parallel support members each having an upper curved mask sheet support surface, said parallel support members each having a longitudinal extent along the mask sheet;
• providing a mask sheet having parallel slits;
• providing a mask sheet support plate extending from the one parallel support member to the opposite parallel support member and which fits between the two support members, said mask sheet support plate having an upper surface which is curved in a same curvature as said upper curved mask sheet support surfaces;
• setting the frame with the mask sheet support surfaces facing upward and positioning the frame;
• positioning the mask sheet support plate between the two parallel support members so that said upper curved surface of said mask sheet support plate coincides with the parallel support member mask sheet upper support surfaces;
• placing the mask sheet on the curved upper surfaces of the parallel support members and plate;
• fixedly positioning the mask sheet on the frame;
• and
• attaching the mask sheet to the support members.