Patent GB-104962-A (GB)
Title: An Automatic Machine for the Manufacture of Stems for Metallic Filament Electric Lamps.
IPC: C03B23/049
Filed: 1916-05-12
Abstract: 104,962. Morris & Whitham, and Allison, J. A. May 12, 1916. Forming supports for electric-lamp filaments; cutting glass.-A machine for making stems for metal-filament lamps comprises means for holding a glass rod, heating it, upsetting it to form a collar B, Fig. 6, and cutting off the required length. In the construction shown in Fig. 1, chucks e, e<1> are carried by alined shafts d, d<1> having bearings c, c<1> on a bed b. One shaft d is hollow, so that the glass rod can be fed through it: the other is telescopically adjustable, to vary the length of the stem. The chuck on the latter shaft also forms a stop for the end of the glass rod. A loose driving-pulley f on the hollow shaft d can be coupled thereto by a clutch f<1> operated by a handle f<2>. The second shaft d<1> is driven from the first shaft d by a parallel shaft g and tocthed gearing. A shaft i below the bed b is also driven from the hollow shaft d through reducing- gearing and bears cams for effecting the various operations. A blowpipe r, preferably having four fine air-jets, is mounted on a carriage sliding on rods q<1> at right-angles to the shafts. The carriage is pressed away from the glass rod by springs, but forced inwards, when heating is required, by a cam and curved lever. Two fishtailed plates v support the glass rod and limit the area of heating; they are lowered by means of a cam when not required. Upsetting is effected by movement of the right-hand shaft d' endways by a coil spring p<4> when permitted by a cam p, which acts on a lever p<1> pivoted to a loose collar p<2> bearing against a fast collar p<3>. In the outer position of the blowpipe carriage, a pipe s thereon directs a cooling air-jet on to the glass. The right-hand chuck is then opened and is withdrawn clear of the rod by the cam p. A second carriage w, sliding on the same rods as the blowpipe carriage, brings a steel cutting-disk x against the glass rod. Ratchet gear, operated by a lever engaging a stop, turns the disk slightly during its return motion. The disk x is mounted in arms which can rock under control of a spring and an adjustable stop on the carriage. Thus, the carriage can move farther after the disk meets the glass rod, in order to trip a lever z mounted on the carriage. This lever breaks off the finished stem from the rod. Each chuck e or e<1> comprises a pair of pivoted grooved jaws urged apart by a blade spring, but normally forced together by the wedge action of a sliding sleeve k or m<1> pressed backwards by a coil spring within it. In order to open the chuck e when the glass rod is to be fed forward, a cam k<1> and lever k<2> force the sleeve of the chuck forwards. A cam m<2> for opening the right-hand chuck e' acts on a vertically sliding, rod m<3> connected to a bell-crank m<4> carrying an adjustable roller m<5> to engage a lever m<6>. The forked end of the lever m' is pivoted to a loose collar m' resting against the sleeve m' of thet chuck e<1>. When the collar m<7> is forced forward to open this chuck, a pawl on the collar drops behind a collar on the shaft d'. The chuck is thus held open until the pawl is tripped by a lever n<1> and cam n, the chuck c<1> being meanwhile withdrawn clear of the glass rod, and the stem cut off. According to the Provisional Specification, the cutting-disk may be hardened by sulphuric acid.