GB891764A - Improvements in and relating to the lampholders for screw cap or bayonet cap lamps - Google Patents

Abstract

891,764. Lamp holders. CHAUME, J. April 14, 1958 [April 19, 1957; March 6, 1958], No. 11758/58. Class 38 (1) A lamp holder 1 (Fig. 2) made of resilient plastic material, has mounting means, which may consist of a slot 5 adapted to receive a mounting bar, and contacts formed by lugs 4 and 7, the lug 4 having an arm 4a which contacts the lamp cap body and lies in a groove 3 while the lug 7 has a contact 9 co-operating with the centre contact of the lamp cap. The lamp may be secured in the holder by a bayonet connection or may have a screw thread on the cap which co-operates with a screw thread 2, or with fragments of a screw thread, or with pips 18 (Fig. 8), in the bore of the holder. In either case pressure of the lamp cap tip on the bottom of the holder, when in its fully inserted position, deforms the holder so that it grips the lamp and secures it against loosening by vibration. The holder may be mounted by providing it with a T-section projection or studs co-operating with suitable apertures in a carrying plate. Alternatively, it may be mounted in a carrying plate, the edge of the plate surrounding the holder fitting between lips of a peripheral flange integral with (20 in Fig. 15) or screwed on to (25 in Fig. 19) the body of the holder. In another modification the edge of the plate may be deformed to co-operate with a screw thread on the outside of the holder. Rotation of the holder in the carrying plate may be prevented by a projection on the flange fitting into a notch in the plate.