US2272744A - Electric hand lantern - Google Patents

Description

Feb. l0, 1942. J. r. HELLING ELECTRIC HAND LANTERN Filed June 27, 1959 W. TE NH E VE NR lo JB'HN IT-#Eon I FIG. II

FVI'TORN Ey Patented Feb. 10, 1.942

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ELECTRIC HAND LANTERN .lohn Theodore Helling, Auckland Park, Johannesburg, South Africa Application June 27, 1939, Serial No. 281,318 In the Union of South Africa June 28, 1938 1 Claim.

This invention relates to electric hand lanterns which depend for their electrical energy on accumulators or secondary batteries incorporated in the lanterns.

It is particularly applicable to lanterns for use in mines and places where they are used regularly; are liable to very rough handling during service and are available for charging between service periods.

The object of the invention is to provide a lantern which will be as shock proof as possible and for this purpose there is used in its construction as much rubber as is practicable.

A further object is to provide a lantern of this type in which the accumulator is well packed to keep it in good condition, reduce evaporation and prevent spillage of the electrolyte.

The special design and construction of the lantern aims at producing a robust, eilicient and economical source of light whilst having the least possible weight and capable of being recharged without dismantling any of its parts.

According to this invention the lantern is as far as possible made of a resilient material, so

that the lantern will rebound from falls or blows and thus avoid damage. Therefore the container for the cells is made of rubber or similar resilient substance which, whilst being an insulator, will resist the electrolyte and be hard enough to keep its shape. The lamp house, with, if desired the reflector, is also made of resilient material such as rubber, so as to absorb and cushion any shocks and spring back to its normal form after encountering any blows. In other words the inventionprovides a lamp which will withstand falls and rough usage incidental to mining, and still retain its efliciency.

A lantern according to this invention is illustrated in the accompanying drawing in which- Fig. I is a view of a preferred construction of the lantern, partly in section, and,

Fig. II is a side view of a lantern having an extra reflector.

In the drawing l is the casing of a rubber or similar resilient material moulded in one piece so that the casing comprises a boX part 2 and a lamp housing and reflector 3.

The chambers 4, in part 2 are provided with a cover 6, of hard rubber or like material, and in these chambers is built up the electric accumulators. Any suitable type of accumulator may be used, that is, either the acid or alkali type, but it is essential that the various parts making up the accumulator be so packed and held in place as to resist shock. In the form illustrated, sponge rubber is used and is shown in the drawing at l. 3 is the dividing wall between chambers 4 and 5.

The surface 9 of part 3 acts as a reiiector and its reilecting capacity is increased by spraying or painting the moulded rubber surface. l!! is a transparent cover or lens which may be snapped into place in the annular V-shaped groove Il formed in the rubber moulding. I2 is a support for the lamp i3 which is connected by wires I4 to the battery terminals l5 and a switch I6 of any suitable type may be provided.

A handle may be moulded with the rubber casing, but generally it is preferred to provide a metal cage embodying a carrying handle Il. In the illustration, ll is a bent metal handle secured to a metal cover plate I8 which is provided with a depending tongue I9 forming a hook for fastening the lantern to a belt. 2l! is a stirrup shaped metal strap with its ends 2| projecting up through slots 22 in the cover i8, leaving projecting pieces 23 which may be secured in place by bending the metal over the plate I8. If desired the projections 23 may be welded in place so as to prevent the lamp being opened. 24 are holes in the rubber wall of the container 2, and 25 are metal thimbles forming the charging terminals for the accumulator and are Xed in the cover 6 and so placed as to be accessible to contact plugs entering through the holes 24 for charging the accumulator. A hole 26 in cover plate I8 may provide a vent through which any gasses from the accumulator can escape. hole v26 is located over a hole 2l in cover B. Between cover 6 and plate I8 is a pad of sponge rubber or other suitable absorbent material which will allow the passage of gas but will prevent the electrolyte from spilling.

In making use of a lantern according to this invention, particularly where it is used as a miners lamp, it is normally housed -on a charging stand provided with a place for each lantern, which has a power supply connection taking the form of projecting terminals carrying the charging current. Said terminals are adapted to enter holes 24 and make electrical contact with Vthe thimbles 25. When required the lantern is pulled oli the terminals and taken from its stand when it should be charged sufficiently to give service for the length of the shift, say eight hours.

Usually the accumulator will be a normal four volt accumulator and of such size that it will keep a lamp burning for the full shift. O-n coming 01T shift the lantern is returned to the charg- The ing stand and charging takes place until the lantern is required for the next shift.

At proper periods a few drops of distilled water or other liquid required to make up for loss of the electrolyte is squirted into the case 2. This is conveniently done by a syringe entering through the hole 26 and piercing the pad 28, so that the electrolyte can be introduced into the accumulator through hole 2l in the cover. The sponge rubber packing 1 absorbs the electrolyte and will not allow it to spill. Holes 26 and 2l are duplicated (not shown) for servicing the second compartment of the accumulator.

It will be observed that without cutting or burning away the welds 23 it is impossible to open the accumulator and therefore the lantern is very suitable for use in coal mines and similar places where there may be combustible gases present in the atmosphere and consequent danger of explosion.

When desired, the casing may be made sumciently large to accommodate a second accumulator, and suitable switches provided to connect one or both accumulators either in series or parallel with Ithe lamp bulb.

Should a special reflector be desired, for instance to throw a concentrated beam of light, a special metal or other suitable reflector may be iitted into the lamp housing and be kept in place and protected by the cover IU.

In a modied construction, as Shown in Fig. 2, the lantern may have a double lamp housing 3 one on either side; one of which may be coloured red as a warning signal.

An electric lamp having an accumulator or electric cell and the lamp housing moulded all in one piece, is known, but heretofore the housing has been made from ceramics, glass or other rigid insulating material which is liable to deformation or breakage if subjected to falls or knocks incidental to mining work.

This invention provides an electric lamp which is entirely resilient so far as its casing is concerned, and therefore made to withstand falls or knocks. Whilst the lantern is made robust enough to stand rough usage it is kept as light in weight as possible.

What I claim as new and desire to secure by f Letters Patent is:

An electric hand lantern comprising an accumulator casing having cell partitions and a lamp housing formed with a reiiector surface and a recess for a lens all moulded in one piece of resilient material, said accumulator casing having a cover of similar material, passages in the cover to allovl7 the escape of gas, inserted charging contacts allowing charging of the accumulator whilst sealing the contents against spilling, a stirrup shaped cradle of rigid material forming a handle for carrying the lantern and supporting the resilient body of the accumulator and means for locking the cradle round the body of the lantern to prevent unauthorised access thereto.

JOHN THEODORE HELLING.

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