Patent GB-706449-A (GB)
Title: Improvements in and relating to lamp base printing mechanism
IPC: H01J9/30
Filed: 1951-12-11
Abstract: 706,449. Printing on the bases of electric lamp bulbs. BRITISH THOMSON-HOUSTON CO., Ltd. Dec. 11, 1951 [Dec. 16, 1950], No. 28992/51. Class 100 (2) A mechanism, for printing on cylindrical objects, e.g. on the bases of small electric lamp bulbs periodically presented in a work station, e.g. in a rotary turret lamp-making machine, comprises a pair of slide rods 10, 11, Figs. 1a, 1c, mounted substantially parallel and adapted to move forward from the position of Fig. 1a towards the lamp 1, a pair of gripping jaws 7, 8 mounted on radial springy arms 12, 13 on the rods, a marking stamp 6 carried on one of the jaws, means for rotating the slide rods to bring the jaws together to grip the base of the lamp and means for moving one of the slide rods with respect to the other to rotate the lamp between the jaws so that the periphery of the base of the lamp is rolled against the stamp 6. The rolling action, shown in Fig. 1c, is provided by the equal and opposite movement of the two slide rods so that the axis of the lamp remains stationary. The slide rods are mounted in a guide block 37, Fig. 3, and oscillated longitudinally by levers 27 pivoted at 28 to members displaceable by screws 44 to adiust the working stroke of the slide rods. Cam followers 31 on the levers 27 co-operate with cams 32, 45. The rods are tilted by the vertical movement of a slider 54 which is urged by a spring 57 into engagement with a cam 56. A cross-piece 53 on slider 54 is formed with horizontal slots 51 receiving rollers 49 carried on pins 47 projecting from the inside faces of the slide rods. The lamp is held in a bracket 21, on holder 16, by a rod 23 upwardly urged by a spring 25 and pressed downwardly at the right time by a roller 82 to release the clamping pressure on the lamp so that it may be rotated by the jaws 7, 8. As the slide rod 10 moves from its initial position towards the lamp the stamp 6 is swung inwardly so as to wipe across an inking plate 61 rotated slowly and inked by a vertical roller 64 reciprocating with slide rod 10 and, at the end of each stroke, engaging an horizontal roller 65, rotated by a ratchet wheel and pawl, feeding ink from a reservoir 66. The amount of ink fed to the plate 61 is governed by the engaging pressure between the rollers 64, 65, the former being of rubber or the like. The pressure is adjustable by thumb screw 44. To prevent the stamp being inked when no lamp is presented at the work station for printing an interlock is provided preventing the inward swinging movement of the jaw 7 in such a case. This consists of a lever 73 having near one end a roller 76 normally engaged, as the turret rotates to bring a new lamp to the work station, by a peg projecting from the retaining rod 23 so that the lever 73 is displaced to cause the head of a screw 78 carried at the other end thereof to clear a peg 79 projecting from the controlling slide 54. When there is no lamp in the holder 16 the rod 23 is in a higher-position and consequently the peg misses the roller 76 and the screw-head 78 remains-in the path of the peg 79 preventing upward displacement of the slide 54 and rotation of the rods 10, 11. In either case the lever 73 is tripped to free the slide by contact of the projection with a second roller 77 as the lamp holder 16 moves to the next position. Specification 702,098 is referred to.