| Show A new miner mi ner s electric electra c lamp contributed the general electric company is offering a new miners electric lamp that is entirely safe to use of very strong construction yet light in weight simple in design foolproof very efficient in operation and of sample guaranteed capacity the outfit consists fists essentially of a lead plate battery car fried aled on the belt a three quarter candle power jower mazda lamp with a suitable reflect tor jor held in a steel shell carried on the cap and a strong serviceable cable connect ing the battery and the lamp owing to the hazardous nature of work i gaseous mines a demand has been grown N tor for some time for a practical portable IlIc lamp mp that an electric lamp would e safe to use has been well recognized because ile it could be made so that it would not nite unnamable in namable gases and would produce oT 1111 light regardless eSa dIess of atmospheric minions Mit ions while the carbon filament lamp le presented represented the best available electric allu nant auch ch a miners lamp was not pos ible e because of the relative inefficiency of tae e kanip P f for or storage batteries of the re wred d ca capacity acety could not be designed with weight and dimension limits 4 the perfection of the eff efficient lelent mazda lamp in miniature sizes by the general electric company and the development of small efficient fici ent light weight storage batteries has resulted in the design of the long desired type BL for B R miners electric lamp the prime feature of this lamp is that it has been made thoroughly safe to use by adequate insulation of the entire circuit placing all terminals and contacts inside of locked and sealed steel cases and providing automatic means for extinguishing instantly the glow of the fl filament lament should breakage of general eclectic companas Comp anys miners electric lamp the lamp bulb expose it to the air this lamp built of high grade materials 2 has been made both safe and rugged the outfit complete weighs but 3 lbs ibs of which 3 lbs ibs are carried on the belt and 4 oz on the cap the battery is rated at 72 amp hr normally it will light the lamp 12 hours per charge and can be relied on to furnish light at least 10 hours per charge at the end of one years service the ya cp c p mazda lamp operates at 19 volts and the reflector distributes the light evenly through a solid angle of about deg the battery is non spilling and the ter finals are not subject to acid corrosion the case is of medium hard ruber egide plates are used the battery box measures 61 inches high by 5 inches wide by 2 inches thick overall it is made of drawn sheet steel w welded elded including the two side straps for the miners belt after welding the box is lead plated and painted with acid proof paint the cover is drawn steel hinged at one end and fitted with a substantial lock at the other end the terminal contact block is riveted to the inside of the cover connection to the battery terminals is made by strong spring contacts arranged to close the circuit when the cover is shut the cable entrance bushing is water tight and clamps the cable firmly to prevent strain on the terminals the lamp bulb reflector and terminal contact block are encased in a light strong drawn steel shell which is copper oxidized enameled and provided with a hook for attaching to the miners cap the entrance bushing leads the cable through the back of the shell where it is reinforced by a steel plate on the terminal contact block which is waterproof and screwed to the protecting shell are mounted suitable terminals for cable connections and the spring contacts which hold the lamp bulb the contacts are nickel plated the reflector is of drawn steel white porcelain enameled A rubber gasket between this and the glass renders the case waterproof the glass is held by a phosphor bronze retaining ring which has its ends looped and flattened to extend through slots in the rim of the case for aseal wire if desired the mazda lamp bulb has it its filament inserted and connected with a base contact in the usual manner and at the tip of the bulb is a duplicate contact to which the fl filament lament is connected by a fine copper wire along the outside of the glass the bulb is held at the focal point between the contact springs which maintain it constantly under stress so that in case of a blow otherwise only sufficient to chip or partly break the bulb it will be completely shattered by the springs and will drop clear of the contacts sufficient space is provided between the reflector and glass cover to keep broken lamp parts from short circuiting the spring contacts this prevents the possibility of ignition even if the cap lamp is s seriously damaged amid explosive gases the cable consists of two braided strand rubber covered conductors each having a steel piano wire at the center these are twisted together and then heavily rubber covered making the cable able c strong wellin well in sulfated and not liable to kink the ends are protected from wear and damge by flexible steel armor to meet practice analogous to that of flame lamps this ele electric etric lamp is designed to be supplied to in miners iners from the lamp house the outfits are to ibe be assembled and locked with the lamps burning b when delivered and are to be returned to the lamp house in the same condition at the end of the shift no care or attention whatever is required from the miners direct current only should be used for charging in some instances mercury arc rectifier or motor generator sets may be required to change alternating current into suitable direct current small sets adapted for this purpose can be supplied readily charging racks arranged for charging batteries conveniently in quantities are also off offered ered |
