| 摘要 |
457,815. Perforated sheets; thermionic valves. BRITISH DRIVERHARRIS CO., Ltd., Gaythorn Mill, Albion Street, Manchester. June 7, 1935, No. 16569. Convention date, March 29. [Classes 83 (ii) and 83 (iv)] Rolling; shearing ; angular bending. - Electrodes for thermionic valves &c. are formed of thin strip perforated, to form burrs projecting from one side, which are flattened to bend the burrs against the side of the strip. The perforations are formed by passing the strip 14 through rollers, Figs. 9, 10. The strip is then reversed and passed through a third pair of rollers 2, 4 which bend the burrs 16 to the shape shown in Fig. 8. Further rollers flatten the burrs, Fig. 11. The flattening rollers may be omitted. The perforating rollers are formed by cutting transverse and circumferential grooves in master roller and running roller blanks with the master roller to emboss the blanks. |
