| 摘要 |
370,981. Electric battery lamps. GENERAL ELECTRIC CO., Ltd. and RICHARDS, S. W., Magnet House, Kingsway, London. Jan. 13, 1931, No. 1216. [Class 39 (ii).] For controlling the detonation of an explosive charge a miners' battery lamp is provided with means including a removable key, whereby the current of the lamp battery which is normally unavailable for effecting detonation may be made available for that purpose. As shown in Fig. 1, members 3 extending upwardly from the lid 1 of the battery casing support a casing 4 which is provided with a screwed-on lid secured by a magnetic bolt. The removable key or plug, shown in Fig. 3, is adapted to be connected by flexible leads to the charge to be detonated, and is connected to the battery by inserting it within a tubular socket 8 secured in one side of the casing 4. The socket 8 is provided with a flange 9 adjacent to a screwthreaded part 10 which is insulated from the side of the casing by a bush and washer 13, a nut 14 being screwed on to the part 10 within the casing to secure the socket 8 in position. A metal plunger 15 adapted to slide within the socket has a cylindrical head 16 formed with a recess in its end, and carries a piston 19 of insulating material which is screwed thereon and abuts against a helical spring 23 retained within the bore of the socket by an apertured plug 21. The removable plug, Fig. 3, is adapted to be pushed against the end 17 of the piston to force the plunger 15 through the aperture 22 of the plug 21, so that the end 20 of the plunger bears against a projection 30 on the end of a metal contact strip 26 which, together with contact strips 24, 25 is mounted on the exterior of the socket 8. The strips 24, 25, 26 are insulated from one another and from the socket 8 by blocks 27, and screws 28 which retain them in position are located within insulating bushes to provide a circuit between the upper strip 24 and the socket 8. The contact strips 25, 26, separated from one another by an insulating strip 47, are connected to the battery terminals, so that when the plug is inserted into the socket and the end 20 of the plunger makes contact with the projection 30 on the contact strip 26 the strip 25 is lifted against the strip 24, and the detonating circuit is completed. The plug comprises a handle 32, Fig. 3, of insulating material with an axial bore containing a central metal stem 34 which is separated from a surrounding- metal tube 33 by an insulating sleeve 35, the stem and tube respectively being provided with terminals 42, 40 enclosed within an insulating-cover 43 for the attachment of the leads to the explosive charge. |
