GB402735A - Improvements in or relating to capless electric incandescent lamps or discharge tubes and holders therefor - Google Patents

Abstract

402,735. Electric incandescent lamp caps. NAAMLOOZE VENNOOTSCHAP PHILIPS' GLOEILAMPENFABRIEKEN, 13D, Emmasingel, Eindhoven, Holland. March 3, 1932, No. 6464. Void [Abridged as open to inspection under Sect. 91 of the Acts, March 6, 1932]. [Class 39 (ii).] A capless electric incandescent lamp bulb, or an electric discharge tube such as a thermionic transmitting or receiving valve, X-ray tube or the like, is detachably connected to a cap by the interengagement of members which are coupled together by a straight pushing movement. The bulb 1, Fig. 1, is provided with a stem-tube 2 and pinch 3 through which the leading-in wires 4 pass at opposite sides of an exhaust tube 6, the cap 8 being provided with an extension 9 which fits within the interior of the stem tube 2 and is provided with two tubular channels 13 each containing a helical spring 12. Pins 10 extending downwardly from the contact plates 11 of the cap are gripped by the upper portions of the springs 12, and when the cap extension 9 is pushed within the stem-tube 2 the leading-in wires 4 pass axially within the lower portions of the springs, the relative dimensions being such that a closely gripping contact is provided. Rotary movement of the cap relatively to the bulb may be prevented by pinching a portion of the stem-tube 2 so that it is of the crosssection shown in Fig. 4, and making the capextension 9 of corresponding non-circular section. In a modification the cap 22, Fig. 5, is provided with blade-springs 23 which are offset at their lower ends to form a recess 24 adapted to engage a right-angled bend 21 at the upper ends of the leading-wires 18, the form of the springs 23 being such that they press the bent ends of the leading-in wires against the exhaust tube 20 and ensure greater rigidity.