Patent GB-825712-A (GB)
Title: Apparatus for transferring electron tube assembliers from a prcheater to a sealing machine
IPC: B23Q7/04
Filed: 1956-10-09
Abstract: 825,712. Making electron tubes. SYLVANIA ELECTRIC PRODUCTS Inc. Oct. 9, 1956 [Dec. 16, 1955], No. 30793/56. Class 39(2) In making electron tubes a succession of bulb assemblies each comprising a tubulated bulb A, fitted over a mount B on which it is held frictionally with its bottom edge spaced from the glass base C of the mount, are fed through a preheater to a delivery station where a transfer device operates to transfer the bulb and mount assemblies sequentially to an indexing receiving machine provided with a series of equally spaced receiving-pegs, the transfer device being provided with means, movable by and with it, for pushing the bulb further down over the mount to a position such that the bottom of the bulb is opposite the glass base and thereby positioned for sealing thereto. As shown in Fig. 1 an endless chain conveyer 10 consisting of upper and lower longitudinal runs has alternate links provided with clasps for gripping the exhausting tube of a bulb which is thus carried in a relatively inverted condition through a preheater chamber 14 of known type, the tubes being mounted on the conveyer at the end opposite to that shown. The upper run of the chain 10 passes above a long inverted channel bar 22 provided with vertical side flanges supporting at each end a sprocket 20 around which the chain is guided. The side flanges of the channel also support the vertical side plates 24, 26, Fig. 2, of a structure provided with a bottom plate 38 and a transverse intermediate plate 36, the space between the plates 36, 38 forming a housing for the operating mechanism of the transfer device; the lower, or return, run of the, conveyer passes between the plates 22, 36. The transfer mechanism is carried by a platform 50 which is slidable upon a pair of vertical guide rods 44 secured between the plates 36, 38, the tube-gripping jaws 112 of the transfer device being pivoted on a vertically offset front portion 52 of the platform 50, with a cover plate 54 forming a housing for the jaws. Springs 114, Fig. 5,. tend to maintain the jaws normally open their closure being effected by a horizontally slidable cam bar 90 secured to the end of a rod 80 which may be reciprocated at predetermined intervals either by an electric motor or, as shown, by a compressed air device comprising a cylinder 76 with a piston 78, Fig. 4, which is advanced against the pressure of a spring 94 by air fed at controlled intervals through a tube 98. Vertical reciprocation of the platform 50 upon the guide rods 44 is effected by a double ended fluid motor 62, Fig. 2, secured to the underside of.the plate 38 and provided with a piston rod 72 extending between the guide rods 44 and screwed into the platform 50. The inlet and exhaust conduits 70 of the cylinder are connected to valves under the control of the sealing-machines 16. In operation the parts are so timed that when the platform 50 is elevated and the jaws 112 separated the chain conveyer 10, in its indexing movement, inserts the exhaust tube of a bulb between the long grooves in the jaws, whereupon the jaws close and the platform is moved downwardly to thrust the assembly on to a receiving peg 18 on the sealing machine, which has indexed to a position directly below the assembly. In their downward movement the jaws 112 withdraw the exhaust tube from the resilient clasps of the chain conveyer 10 and push the contact pins of the electron tube within a circular groove in the head of the peg 18, Fig. 1. The jaws 112 are next opened to release the exhaust tube, the platform 50 is lifted for the next operation, and the sealing machine indexes the electron tube to the next work station where a presser member 140 is brought downwardly to press upon the upper end of the exhaust tube at the next downward movement of the platform 50. The presser member 140 comprises a pad 146, Fig. 2, yielding material carried by a holder 144 mounted on a vertical shaft 138 which is slidable against a spring within a cylinder 134 secured on the end of an adjustable two-part arm 132 mounted horizontally at the upper end of a vertically slidable rod 128. The lower end of rod 128 is connected to a horizontal carrier rod 120 which is secured by screws to the underside of the platform 50 and extends laterally through a cut away edge of the side panel 24.