GB828020A - Improvements in or relating to supports for tubular envelopes - Google Patents

Abstract

828,020. Discharge lamps. GENERAL ELECTRIC CO. Ltd. July 22, 1958 [July 22, 1957], No. 23146/57. Class 39(1). An arrangement for supporting a tubular vitreous envelope having at least one end closed by a pinch includes a holder for the pinch having a slot into which the pinch is inserted with its faces parallel to the sides of the slot and in which it is gripped between an abutment member on one side of the pinch and a torque on the other, the torque being so shaped and its free end being turned down across the slot so that one edge of the torque bears against the adjacent side of the pinch and presses it against the abutment member. The abutment member may be a second torque. The quartz envelope 1, Fig. 1, of a H.P.M.V. lamp is closed by pinches 7 held in holders 12, the envelope being supported by a wire cradle 14-16 within an outer jacket 11 provided with a luminescent coating. Leads to the main electrodes 3 and auxiliary electrode 8 are provided by molybdenum strips 6, 10 respectively. Each holder 12 is made from mild steel sheet stamped as shown in Fig. 2 to form a channel or slot to receive the pinch and having lugs 33 to which wires 15, 16 of the cradle are welded during assembly. The torques 31 are tapered at their inner edges 35 so that when the pinch is inserted and the torques bent over as shown in Fig. 4, the edges 35 bear against the adjacent sides of the pinch and press it against the cooperating abutment member at the other end of the channel. An aperture 34 is provided in the base 35 of each channel to allow the passage of electrode leads. In the case of a "fish-tail" pinch as shown, the torques prevent longitudinal withdrawal of the envelope from the holder, but for other types of pinch a separate stop member may be provided at the other end of the envelope to prevent withdrawal.