Patent GB-519952-A (GB)
Title: Improvements in and relating to machines for manufacturing filament supports and inserting them into stems for electric incandescent lamps and the like
IPC: H01K3/10
Filed: 1938-10-13
Abstract: 519,952. Making lamp filament supports. AKTIEBOLAGET HAMMARBYLAMPAN. Oct. 13, 1938, No. 29658. Convention 'date, Oct. 16, 1937. [Class 39 (ii)] [Also in Group XXII] A machine for manufacturing filamentsupporting wires and inserting them into stems for electric, incandescent lamps and the like comprises at least one device with a pair of jaws movable to and fro in the direction of the stem and adapted in an outer position to seize the supply wire, draw forth sufficient to form a supporting-wire and hold it during severing and, while the thus freed end is shaped into a pigtail or other form and without altering the grip, inserting the other end into the previously softened glass stem. Fig. 1 indicates diagrammatically the arrangement of the parts comprising a spool 1 carrying the supply wire 2, a guiding-nozzle 3, jaws 4, cutting-mechanism 5, coiling-device 6 for forming the pigtail, and a base or support 8 for the lower end of the stem 7. In addition to the jaws 4 moving to and fro between the guiding-nozzle 3 and stem 7. the cutters 5 and coiling-device 6 are adapted to be moved into and out of their operating position so as not to impede the jaws 4. The jaws comprise a pair of grippers 41, 42, Fig. 3, respectively mounted on the ends of concentric cylindrical members 45, 46 within a horizontal tube 43. A helical spring surrounding the inner member 46 has one end attached thereto whilst the other end is attached to the outer cylinder 45, and tends to hold the jaws closed. Opening of the jaws is effected through pins 48, 49 which project downwardly from the members 45, 46 and extend on either side of a flattened arm 85, Fig. 2, which is turned about its own axis by the vertical movement of a,push rod 84 coupled to its rear end, thereby forcing apart the pins 48, 49. The jaw carriers are moved to and fro by movement imparted by a rotatable die 37 which is mounted on the upper end of a cranked lever 34 and engages between'the pins 48, 49, the other end of the lever being pivoted at 35. A lateral pin 33 at the angle of the lever is engaged by a bifurcated arm 32 carried on a vertically reciprocating rod 31. Cutting apparatus.-The cutters comprise two co-operating members consisting of a vertical tube 52 which is slotted at its lower end and encloses a cylindrical segment rotatable relatively thereto, this device being supported on an arm 17. The upper ends of the cutters carry lateral arms 55, 56 which can be moved outwardly against the tension of a spring 57 by means of a wedge-shaped member 62 disposed between them on the end of a rocking-lever 63. The lowering of this end of lever 63 also produces lowering of the cutters by a spring finger 65 on lever 63 depressing a lever 64, carrying. a lateral finger 61 which engages between, the arms 55, 56 at the top of the cutters and presses the latter downwardly until a collar 54 fixed on the cutter-guide 53 engages the bracket 17. Due to the resilient connection, however, the lever 63 is able to continue its downward movement to actuate the cutters at the requisite moment. Lever 63 is operated by a reciprocating vertical rod 68 linked to its end. The pigtail is formed by a cylinder 71 having a cam on its end so that when rotated it seizes the wire and forms a loop round a mandrel 73. The cylinder is mounted on an arm 77 and driven by a sector 79 actuated as the aggregate 20 is raised. The cylinder is raised when operative and moved. in towards the filament support by vertically moving rolls (not shown), the arm 77 being pivoted with the sector 79 on a shaft carried in a nave 75 which is rotatable on a vertical pivot 18. Upturned and downturned pigtails may be formed alternately -by changing the rotation of the pigtail mechanism. Several units 'as above described may be arranged in various ways according to the type of stem to be made. Thus Fig. 5 shows a number of units mounted in a circle round a common inserting position 2 in concentric slots 3 on a table 4, and Fig. 6 an arrangement for filament supports inserted in parallel relation on a .stem 5.