GB191325210A - Improvements in Miners' Electric Safety Lamps. - Google Patents

Abstract

25,210. Patterson, J. G. Nov. 5. Battery lamps.-In a miner's lamp in which the lantern is rotatable for switching purposes, a ring f, for example of stamped metal, forming the base of a protecting cage, is provided with a depending flange which fits closely over a cylindrical metal case a containing an accumulator. A ring g, secured by means of the cage bars h in the ring f, has a flange at its upper end which is spaced from the depending flange to form an annular recess l, in which the top edge of the case a fits flame-tight. The ring g also carries two segmental projections d, which engage corresponding projections c on two segment-pieces b fixed inside the case a and form a bayonet-joint; extensions e of the pieces b are adapted to position a square or rectangular accumulator in the case. The joint is locked by means of a vertical spring - pressed bolt which passes through the rings f, g and engages the projections c to limit the rotation of the cage; the bolt is released by a magnet. A plate m of celluloid, ebonite, &c., for supporting a glass cylinder and a reflector for holding the lamp bulb, is clamped by a ring k which screws into the ring g. Contacts o, n, connected respectively to the centre contact of the lamp and the reflector and fixed on the underside of the plate m, are movable on and off the battery terminals. Each terminal consists of a metal plunger d<1> actuated by a spring c<1> inside a sleeve b<1> of porcelain, ebonite, antimonial lead, or other acid-proof material screwed on to a lug a<1> of the accumulator. The spring c<1> may be soldered to the lug a<1>. According to the Provisional Specification, the bolt may be locked by a lead plug.