Patent GB-881047-A (GB)
Title: Improvements in or relating to the manufacture of incandescent filament lamps
Inventor: GELDARD ERIC
IPC: H01K3/10
Filed: 1959-06-19
Abstract: 881,047. Fixing support wires to lamp mounts. GENERAL ELECTRIC CO. Ltd. June 17, 1960 [June 19, 1959], No. 21132/59. Class 39(2) In the manufacture of an electric incandescent filament lamp of the kind in which the filament is supported at spaced points between its ends by a number of support wires extending from a glass rod, a plurality of support wires are fed into a mould for shaping the end of the glass support rod, from a single wire feeding means and are received and held in place in the mould by clamps, the mould and the clamps being rotated intermittently to bring each clamp in turn into position to receive a support wire and when all the support wires have been fed into the mould and are held in position by the clamps, the. heat-softened end of the support rod is brought into contact with the mould. The support rod 11 is mounted on a foot-tube 8 carrying also an exhaust tube 9 and leading-in wires 10. The foot tubes are loaded successively into clamps 15 carried by a continuously rotating table 1, e.g. by means such as are described in Specification 832,347. Below each clamp 15 is a drum 20 having an upstanding central peg 23 in which is a recess 24 forming the mould. Six slots 26 spaced at angular intervals of about 40 degrees are formed in the side walls of the recess and opposite each slot is a clamp consisting of a pair of jaws 27 pivoted together at 28 and biased apart by a spring 31. The drum 20 is intermittently rotated to bring each clamp in succession opposite a wire feeding means 47 consisting of a plate 49 having an upturned front edge 62 provided with a slot for the passage of the wire and a block 48 carried by a pivoted arm 60, the plate 49 and block 48 forming a clamping means for the wire. The feeding means is reciprocated in the direction of the radius of the drum and in its forward movement draws wire 50 from a spool 51. During this movement a cam 46 raises a rod 45 passing through the table, to operate a pawl 38 pivoted on the drum so as to depress a spring urged rod 33, the tip of which normally projects between the tails 32 of the jaws 27, and allow the spring 31 to open the jaws. When the end of the wire 50 enters the recess 24, the rod 33 rises to cause the jaws 27 to close and clamp the wire and the feeding means 47 is then retracted, the wire sliding between the plate 49 and block 48. Means (not shown) are provided to cut off the wire between the jaws 27 and the edge 62 and the drum 20 is then rotated to bring the next clamp into position to receive a fresh end of wire. When wires have thus been fed to all or a selected number of slots 26, a cam 66 moves the support 14 for the clamp 15 downwards, the end of the rod 11 having been heat-softened in the meantime by means not shown so that the downward pressure fans a button on the end of the rod into which the ends of the wires 50 are sealed. A cam 58 then depresses a rod 52 carrying a plate 54 engaging the lower ends of all the rods 33 so that all the sets of jaws 27 are opened simultaneously, the clamps 15 are raised lifting the end of the rod 11 from the recess 24 and the finished supports are unloaded from the machine, e.g. by mechanism similar to the loading mechanism.