Improvements in Apparatus for Lighting Miners' Safety Lamps.
Year: 1894

page_text: Date of Application, 15th Mar., 1894
Complete Specification Left, 13 h Dec., 1894-Accepted, 9th Mar.. 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Lighting Miners' Safety Lamps.
We, BENJAMIN MAWSON, of Street Lane, Gildersome, near Leeds, Engineer,
and WILLIAM BEST, of Wesley Street, Morley, near Leeds, Foreman Lampman,
both in the County of York, do hereby declare the nature of this invention to be
as follows:-
The object of our invention is to construct apparatus in connection with miners
safety lamps, whereby such lamps may be lighted in a safer and more expeditious
manner than heretofore, whilst at the same time such apparatus is not liable to
misfire, nor does it diminish the light when the lamp is burning.
In the Specification of a Patent granted to Graham and Chapman, dated the
10th day of April 1893 No. 7286, an electrical lighting device is shown and
described, in which a stationary carbon and a moving carbon are employed in
conjunction with other mechanism, whereby an electric circuit is completed and
theu broken, causing a flash which lights the wick of the lamp.
In making practical experiments with lamps constructed according to Graham
and Chapman's Specification aforesaid, we have found serious defects which render
the invention impracticable in its present state. According to their invention it is
necessary to employ the stationary carbon projecting above the level of the wick,
in order that the moving carbon may come in contact therewith on crossing the
wick. The projecting of the stationary carbon deprives the wick of a portion of its
air supply, thereby diminishing the flame of the lamp considerably, whilst at the
same time the lighting device is liable to misfire should a portion of the wick come
between the two carbons.
According to our invention we attach the stationary carbon to the side of the
wick holder of the lamp, in such a manner that the upper surface of the carbon is
at or below the upper edge of the wick holder. The movable carbon is mounted
on the lamp at the same side as the stationary carbon, and we prefer to mount the
said movable carbon on an arm carried by the upper end of a metal spindle, which
latter passes through the lamp bottom by way of an insulated tube.
By connecting the opposite poles of an electric generator respectively to the
spindle and to the lamp bottom, at the same time turning the said spindle, the
carbon on the end of same is brought in contact with the carbon on the wick holder,
and the electric circuit is completed. On separating the said carbons the current is
broken and a flash takes place which immediately ignites the wick, which latter has
already become heated by the passage of the current down the wick holder to the
base of the lamp.
By having the upper surface of the carbon at or below the upper edge of the wick
holder, the light is not diminished, as is the case with the employment of a carbon
projecting above the level of the wick holder; and by having the two carbons
situated on the same side of the wick holder, the necessity of crossing the wick
is dispensed with, and the danger of the wick coming between the carbons and
preventing contact is entirely obviated.
The spindle carrying the moving carbon may be turned by means of a crank
situated on its lower end, the said crank being actuated in any suitable way.
Dated this 15th day of March 1894

page_text: Improvements in Apparatus for Lighting Miners' Safety Lamps.
We, BENJAMIN MAWSON of Street Lane, Gildersome, near Leeds, Engineer,
and WILLIAM BEST of Wesley Street, Morley near Leeds, Foreman Lampman,
both in the County of York, do hereby declare the nature of this invention, and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
The object of our invention is to construct apparatus in connection with miners
safety lamps, whereby such lamps may be lighted in a safer and more expeditious
manner than heretofore, whilst at the same time the light is not diminished and
misfiring is entirely obviated.
In the Specification of a Patent granted to Graham and Chapman, dated the
10th day of April 1893 No. 7286, an electrical lighting device is shown and.
described, in which a stationary carbon and a moving carbon are employed in
conjunction with other mechanism, whereby an electric circuit is completed and
then broken, causing a flash which lights the wick of the lamp.
In making practical experiments with lamps and lighting apparatus constructed
according to the Specification aforesaid, we have found serious defects which
render the said invention impracticable in its present state.
According to Graham and Chapman's invention and as shewn at Fig. 1 of the
accompanying drawings, a stationary carbon A is fitted to one side of the wick
tube B, so as to project above the level of the said wick tube B. A movable
carbon C is mounted on a spring D on the opposite side of the wick tube to that of
the carbon A, and the said movable carbon C has to cross over the wick B' in order
to come in contact with the stationary carbon A. It will be readily seen that the
projecting of the stationary carbon A. above the level of the wick tube B, deprives
the wick B of a portion of its air supply, thereby diminishing the flame of the
lamp considerably, whilst at the same time the lighting device is liable to misfire,
should a portion of the wick B' come between the two carbons A and C.
Sliding bars E and F are employed for actuating the spring D of the movable
carbon C, the bar E being situated on the lamp bottom G, whilst the bar F is
carried in a bracket H situated on the body J of the lamp, consequently unless the
lamp bottom G screws up absolutely true, the two bars E and F will not coincide,
and the lighting apparatus cannot be actuated. A stationary bracket Kis connected
to one pole of an accumulator or dynamo, the opposite pole being connected to, a
spindle L working centrally in the bracket K. The bracket H on the lamp body is
brought into contact with the stationary bracket K, and in order to light a lamp,
the spindle L in the bracket K is pressed forward, which simultaneously moves the
sliding bars E and F. Should the spindle L be, pressed too hard, the lamp is
moved bodily back, breaking the circuit at the juncture of the two brackets H
and K and producing an external spark.
According to our invention, and with reference to Fig. 2 of the accompanying
drawings, we mount the stationary carbon A in a box A, which is attached to one
side of the wick tube B in such a manner that the upper surface of the said carbon A
is at or below the level of the upper edge of the wick tube B. The movable
carbon C is mounted on a spring D at the same side of the lamp as that of the
stationary carbon A, and such movable carbon C may be actuated by similar
mechanism to that described in the Specification of Patent No. 7286 of 1893
aforesaid. By having the carbon A at or below the upper surface of the wick
tube B as above described, the light is not diminished, as is the case with a carbon
projecting above the level of the wick tube; and by having the two carbons A
nd C situated at one and the same side of the wick tube B, the necessity of the
rbon C crossing the wick B' is dispensed with, and thus the danger of

page_text: misfiring by the wick B' coming between the two carbons A and C and preventing
contact, is entirely obviated.
In order to actuate the movable carbon C in a more efficient manner, and at the
same time to obviate an external spark taking place when lighting the lamp, we
dispense with the spring D, sliding bars E and F, bracket H, stationary bracket K,
spindle L and parts connected therewith shewn at Fig. 1, and employ apparatus
shewn at Figs. 3 and 4 of the accompanying drawings, in which the movable
carbon C is mounted on an arm M carried by the upper end of a metal spindle N,
which latter passes through the lamp bottom G by way of an insulated tube P.
The spindle N carrying the moving carbon C may be turned by means of a crank R
situated on its lower end, the said crank being actuated in any suitable way.
By connecting the opposite poles of an electric generator respectively to the
carbons A and C, and bringing them in contact one with the other, an electric circuit is
completed, the passing current causing the oil in the wick B' to become warm. On
separating the said carbons A and C, the current is broken and a flash takes place,
which immediately ignites the already heated wick B'.
It will be readily understood from the above description, that whereas the
apparatus described in Graham and Chapman's Specification of Patent aforesaid is
practically unsuccessful, it has by the employment of our invention been converted
into a practical and commercial success.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
:-
1. A stationary carbon attached to the side of the wick tube of a lamp, the upper
edge of the carbon being situated at or below the level of the upper edge of the wick
tube, substantially as and for the purposes set forth.
2. The carbon A, in combination with the carbon C, both situated at the same
side of the wick tube B, substantially as and for the purposes set forth.
3. The combination of the carbon A, box A', wick tube B, carbon C, spring D,
and lamp bottom G, substantially as and for the purposes set forth.
4. A spindle N carrying the movable carbon C on its upper end, and passing
through the lamp by way of an insulated tube, substantially as and for the purposes
set forth.
5. The combination of the carbon A, box A', wick tube B, carbon C, arm M,
spindle N, lamp bottom G, insulated tube P, and crank R, substantially as and for
the purposes set forth.
Dated this 13th day of December 1894.