Patent GB-449590-A (GB)
Title: Improvements in and relating to machines for manufacturing incandescent electric lamps
IPC: H01J9/46
Filed: 1935-07-01
Abstract: 449,590. Making electric incandescent lamps. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London. July 1, 1935, No. 18816. Convention date, June 30, 1934. [Class 39 (ii)] In a machine for making electric incandescent lamps of the miniature type the mounts, of the form shown in Fig. 2, are made first in a machine A, Fig. 1, of the turret type described in Specification 264,805, [Class 39 (ii)], and are carried round to unloading mechanism B which transfers them to position S. During transfer a testing current is passed through the leading-in wires and filament, a faulty mount causing the unloading mechanism to stop and discard the mount. From position S the mounts are carried by mechanism C to one of a series of storage shoots D which pivot about a central point and tilt down in the direction thereof, so that the mounts slide down towards the inner end and operate counting' mechanism. After receiving a predetermined number of mounts the shoot is swung 180‹ to a stationary shoot E in the unloading position, and is tilted downwardly so that the mounts slide down on to the stationary shoot from whence they are released one at a time at the end T by an escapement mechanism. From the lower end T of the stationary shoot the mounts are taken bv transfer mechanism G to the jaws of a turret at position U and are indexed intermittently to an unloading position V where they are placed successively into bulbs which are fed into the machine through escapement mechanism in a bulb turret K, whereupon the bulb and mount are transferred bv mechanism L to a head W in a sealing-machine M. The seating-machine is of the type described in Specification 252,395, [Class 39 (ii)], wherein an exhausting tube is butt-sealed to the bulb, with the leading-in wires sealed in the joint thus formed, these operations being completed as the bulb assembly is carried anti-clockwise into position X. Unloading and transfer mechanism N then places the bulb assembly on to a conveyer chain O which indexes it intermittently into position Y from whence it is taken by transfer mechanism P and placed in the head of an exhausting-machine Q at position Z. The exhausting-machine is of the type described in Specification 199,362, [Class 39 (ii)]. As shown in Fig. 3, the mechanism for taking the finished mount from the jaws 35, 36 of the mount-making machine A comprises a pair of relatively fixed jaws B<1>, B<2> co-operating with movable jaws B<6>, B' to grip the filamentsupporting wires, the jaws B<1>, B<2> being mounted on an arm B<3> and insulated therefrom. While the mount is held within the jaws it is tested by passing current therethrough from a battery connected in circuit with the jaws B<6>, B'. If satisfactory, the strength of the current through a relay is sufficient to close a mains circuit through a solenoid which withdraws a sliding latch B<53> to allow the arm B<3> to be swung to transfer the mount, otherwise the latch opens the jaws and the mount is released and discarded. The swinging of the arm B<3> is effected by a vertically movable rod B<26> and arm B<27>, and the rod B<26> also actuates a pawl which drives a ratchet wheel provided with a number of teeth corresponding to the number of mounts that can be received in each storage shoot D. At the end of each revolution of the ratchet wheel another shoot is indexed into the mount-receiving position. The storage-shoot loading device C comprises a pair of jaws at the end of an arm which oscillates between the position S, Fig. 1, and the outer end of a storage-shoot D, the jaws being opened to drop a mount on to the rails of the shoot. Eight shoots are provided, arranged radially about a vertical shaft D<14>, and each comprising a pair of side rails D<1>, D<2>, Fig. 11, and a central guide rail D<3>. Each shoot is mounted on a pivot D<12>, Fig. 10, at the outer end of an arm D<10> and, when in the mount-receiving position is pulled by a spring D<16> so that it inclines downwardly and rests on a stop D<17> on the arm D<10>, whereby the mounts slide down against a block D<4> at the inner end of the shoot. After receiving the predetermined number of mounts the shoot is carried clockwise through 180‹ to the unloading position, by its supporting-arm D<10>, this movement being effected by a chain-andsprocket drive on a wheel D<20> on the shaft D<14>. At the unloading position a roller D<43> on the outer face of a block D<11> on the shoot is engaged by a finger E<2> at the upper end of a vertically movable rod E<6> and the shoot is tilted to enable the mounts to run off it on to the rails of a stationary shoot E, Fig. 1. The stationary shoot E comprises a pair of stationary rails E<13>, Fig. 12, and a guide rail E <14> which is agitated by means of a vibrating finger in engagement with a ratchet wheel E<22>, thereby causing the mounts to move progressively along the shoot. In moving along the shoot the mounts pass beneath a pivoted feeler E<24> which is turned at intervals to rest on the edges of the rails or on the mounts thereon. When the number of mounts on the stationary shoot has so decreased that the feeler no longer contacts with a mount, the feeler drops and actuates an electric relay which operates a pawl in engagement with a ratchet wheel and brings another loaded shoot into the tilting-position. During their passage along the stationary shoot the mounts meet an escapement mechanism comprising two pairs of jaws which separate at intervals to release one mount and allow it to slide to the end of the shoot where its progress is arrested by a gate E<68>. The mount is then gripped by the transfer mechanism G carried by an arm G<2> and comprising a stationary jaw G<1> and a pair of movable jaws which are opened and closed by levers actuated by a wedge-shaped lever G<9> located between them. The gate is raised and the arm G<2> carrying the mount is swung clockwise to bring the mount beneath the jaws of the turret H at position U. The turret H is provided with eight pairs of radially disposed mount-gripping jaws, each pair consisting of a stationary jaw H<1>, Fig. 12, fastened to the turret, and a laterally extending jaw H<3> mounted on the stationary jaw, each movable jaw being provided with a roller adapted to engage a cam H<5> which is mounted coaxially with the turret shaft H<13>. A spring H<8> tends to hold the jaws closed, the movement of the opening cam H<5> being provided by a lever H<14> secured thereto and operated from the main cam shaft. The turret is indexed clockwise bv a ratchet mechanism at the lower end of its shaft H<13>, and the mount is carried through 180‹ into position V, Fig. 1. From the turret H the mount is dropped into a lamp bulb which is fed, neck-uppermost, into a tube J<1>, Fig. 12, by apparatus of the type described in Specification 212,412, [Class 117]. The lower end of the tube J<1> is located in a boss J<2>, Fig. 20, into which a finger J4 projects to prevent the passage of a bulb until a pair of jaws J', J<8>, Fig. 21, located below it are closed by a spring J<13>. The jaws J', J<8> are provided with inter-engaging gear segments J<16>, J<17> and are opened by the operation of levers J<18>, J<19>, this action simultaneously introducing the finger J<4> into the bulb-feeding tube to prevent the passage of another bulb. The released bulb falls on to one of the heads K<2>, K<3> of a bulb turret K, Fig. 12, which carries it into a position to be taken by the bulb transferring mechanism L. The bulb is retained in position in a conical seating K<8> in the bulb turret by connecting the lower end of the seating to a vacuum source. The turret is then lowered, turned through 180‹, and raised again, thus placing the other head in position to receive a bulb and placing the head which carries a bulb in position for the transfer mechanism to take the bulb. This transfer mechanism comprises a pair of jaws L<1>, L<2>, Figs. 1 and 12, upon an arm L<5> which is carried by a vertical shaft L<12>, the jaws being mounted on pivots and provided with interengaging teeth, so that movement produced in jaw L<1> by a lever L<8> and actuating cam L<6> causes corresponding movement in jaw L<2>. A spring connected between arm L<5> and lever L<8> tends to close the jaws. The jaws are opened to grip a bulb, after which the transfer device is raised to bring the bulb neck around the mount in turret H at position V. The mount is released from the turret and falls into the bulb, with the outwardly extending portion of the leading-in wires between guides attached to the transfer jaws to keep the mount from turning. The transfer mechanism now swings to a position over the head 49 of the butt sealing machine, and the shaft 12 is lowered until the bulb rests thereon, after which the shaft L<12> is turned, causing the cam L<6> to open the jaws. Means for automatically stopping the feeding of the bulb if a mount is absent from the turret, comprises an electric switch L<39>, Figs. 1 and 12, with a fixed contact L<43> and movable contact L<44> which is operated by an arm L<46> striking a cam L<47> on the post H<9> of the movable jaw of the mount turret, the device being so adjusted that the members L<46>, L<47> clear one another when the turret jaw holds a mount. The closing of this switch operates a solenoid which stops the bulb transferring mechanism. The butt-sealing mechanism M, which is of the type described in Specification 252,395, holds the bulb by suction in a head 49, and grips the leading-in wires in jaws 50, 51. A tube 52 held by jaws 53, 54, Figs. 1 and 12, is sealed to the neck of the bulb with portions of leading-in wires enclosed in the joint.