GB1101565A - Improvements in or relating to cathode ray tubes - Google Patents

Abstract

1,101,565. Work holders. RAULAND CORPORATION. 4 Oct., 1965 [20 Oct., 1964], No. 42,110/65. Heading B2L. [Also in Division H1] Apparatus for coating the faceplate of a cathode ray tube with a viscid material-e.g. polyvinyl alcohol containing a phosphor-permits simultaneous controlled rotation and tilting of the faceplate. The faceplate 5 is mounted on a workholder 23 rotatable about its axis by gear 21 and shaft 16, and tiltable about shafts 16 and 30 by rotation of the latter, to which the housing 20 is secured. Operation of a first control button actuates an hydraulic system which rotates shaft 30 to render the faceplate horizontal, and lowers into place a panel bearing on infra-red heater (Fig. 1, not shown). Actuation of a second control button causes the deposition of a quantity of the viscid coating material upon the faceplate, energization of an electric timer, and simultaneous rotation of shafts 16 and 30, to produce both rotation and tilting of the faceplate, followed by a stay of the tilting motion at a tilt angle of about 30‹, during which excess coating material accumulated at the lowermost edge of the face plate is syphoned off, whereafter the tilting motion is resumed. Immediately thereafter, cams 45b and c engage their cam followers which adjust the hydraulic system to cause the faceplate both to rotate about its axis at an increased speed, and also rapidly to tilt to a substantially vertical position, as shown, whereupon cam 45d actuates its cam follower to prevent further tilting rotation, to switch on the infra-red heaters, and to energize a second timer, which subsequently switches off the heaters, and stops the rotation of the faceplate about its axis.