method and apparatus for applying a bead of material from the surface of the part of the funnel of a cathode ray tube at

摘要

1353988 Coating edges with glass sealing material RCA CORPORATION 11 Aug 1971 [12 Aug 1970] 37642/71 Heading C1M [Also in Division B2] Apparatus for applying glass frit sealing material to the rim surface 16 of an article such as a TV tube 10 where the edge of the rim surface forms a closed configuration with arcuate corner portions 17a to 17d comprises a glass frit material dispenser 23 having an outlet nozzle 93 supported above the rim surface 16 by a support member 102 on -which is mounted a rotatable mounting member 107 by a bearing 106 on a member 103, the member 107 normally rotating about the axis of the nozzle 93, a guide roller 108 being mounted on the member 107 and spring means 120 between member 103 and member 102 biasing the roller 108 against -the side wall 20a adjacent rim surface 16, means being provided for moving the rim surface 16 beneath and with respect to the outlet nozzle 93 and a structure including cam 112 mounted on support member 102 to move members 103 and 107 and thereby roller 108 so that the distance of the nozzle 93 from the edge of the rim surface is charged as the arcuate comer portions of the sealing rim surface move under the nozzle. The apparatus comprises a frame 21 and funnel support assembly 22 including a circular platform unit 24 rotatably supported on frame 21 by guide rollers 33a, 33b, and 33c and joined to a bottom plate 26 by struts 25a, 25b, and 25c, the plate 26 being mounted on the input shaft 31 of a gear-box 32. Plate 26 is driven from drive unit 35, supported on arm 36 pivoted at 37 on frame 21, via a rectangularly shaped member 34 having surfaces 39b corresponding to the surfaces of the TV tube and surrounded by a roller chain 40. Unit 35 comprises a variable speed motor 41 during horizontal input shaft 42 of gear-box 43, allowing adjustment of the linear speed at which the sealing rim passes beneath the nozzle 93, and guide wheel (46) and sprocket (45) on shaft (47) of gear-box 43, the sprocket (45) driving chain 40. Actuator discs 55a and 55b, with actuators 56a and 56b at positions corresponding to the corner portions 17a to 17d of the surface 16 to operate switches 57a and 57b, are mounted on a shaft 59 which is connected by sprockets 63, 64 and chain 65 to the output shaft 66 of the gear-box 32, output ratios being such that the discs 55a and 55b are rotated in direct relationship to that of the funnel support assembly 22. Switch 51a operates an air cylinder (115) to rotate cam 112 at each corner to alter the distance of nozzle 93 from the edge of the rim surface and switch 57b operates to vary the speed of motor 41 at each corner. Container 23 for the glass frit is supported on frame 21 by a vertically adjustable post 70 via bracket 68, pivot shaft 69 and support arm 67, the container 23 being attached by a clamp unit 80 to an upper platform 74 pivotally mounted at 76 on a lower platform 75 of arm 67, stops 79a and 79b limiting pivotal movement operated by a pneumatic cylinder 77. The glass frit is agitated by a vertically reciprocated agitator 91 operated by a motor 82. Cam 112 is mounted on a shaft 110 in bearings 111a and 111b in support member 102 and engages a wear plate 113 on the member 103. Operating air cylinder (115) is attached to a cam operating lever 114 by a clevis 116 and pivot 118 and at its other end pivoted to a bracket 117 attached to support member 102. A counter weight 126 (Fig. 2) attached to lower platform 75 by a cable 122 biases support member 102 so that roller 108 is urged against the inner wall 20a of funnel 14, so that cam 112 therefore moves the nozzle 93 towards the outer edge 20b of the sealing rim 16 at each corner. In a suggested modification, roller 108 may be urged against outer edge 20b and nozzle 93 then moves towards the inner edge 20a.