Improvements in Miners' Safety Lamps.
Year: 1893

page_text: Date of Application, 12th July, 1893
Complete Specification Left, 10th Mar., 1894-Accepted, 14th Apr., 1894
Improvements in Miners' Safety Lamps.
J, WILLIAM SANDBROOK, of Ebbw Vale, in the County of Monmouth,
Ironmonger, do hereby declare the nature of this invention to be as follows:-
This invention relates to improvements in the construction and arrangement of
the parts of miners' safety lamps, and is an improvement upon, or an amplification
of the invention described, and represented in the Specification of the Letters Patent
granted William John Clapp and the present. Applicant, and dated the 4th day of
March 1886 and numbered 3092.
My present invention relates in the one part, to the extinguisher means of the
lamp; in another part, to the automatic releasing of the said extinguisher part; in
a further part, to the upper and open frame part, and in a still further part, to a
duplex lock, whereby the case or shield part is locked to the lamp in common with
the oil tank or base part.
The lower part of the lamp is made up of four component and primary parts,
consisting of an oil tank forming the base, surmounted by a vertically barred frame,
with an outside screwed terminal flange, upon which an inside screw at the mouth
entrance to the case or shield takes, and affixes the said case or shield to the said
lower part, and prevents the ingress of coal dust or other foreign matter to the
interior of the lamp.
Located within the barred frame is a short glass cylinder, with the lower part
resting upon the base, and with the upper part coming within the interior of the
screwed ring at the summits of the bars, one of which is loose and sliding, and to a
lower extension of which, an arm or lever is jointed, and which lever has a gate or
long slot through it, which takes over a staple plate or eyed plate fixed to the
lamp, and which staple plate at the fore part of its top edge constitutes the fulcrum
about which the said lever turns as a centre of motion, whereby the said loose, bar
is slid upwards, and its upper end made to engage with a catch snug or snugs at
the mouth entrance to the case or shield to be locked, so that by passing the
slotted lever over the staple plate for locking the body part of the lamp to its base,
the casing or shield is also and at the same time locked to the lamp.
Disposed or located above the lower part of the body of the lamp, and in the
same axial line as the glazing, and above the outside wormed flange as aforesaid, is
an upright cylinder of wire gauze, connected at its lower end to the said lower
part, whilst its upper end has a top also of wire gauze, upon which a perforated
disc, having an upright stalk or stem proceeding from its middle, rests.
Surrounding the upper portion of the said wire gauze cylinder is an extinguisher
casing, of a greater length or depth than the gauze itself, and which extinguisher
casing is normally suspended about half-way up the wire gauze, or at a suitable
distance from its bottom, by the aforesaid stalk or stem through the medium or
intervention of an extinguisher disc, perforated near its edges, and closed at its
middle, and with the said middle part resting upon a fusible peg or cottar, passing
through the upper end of a stalk:
The extinguisher casing has at its upper end, side piercings, and immediately
below the said side piercings is an inwardly directed flange, which semi-chokes or
contracts the inside of the said extinguisher casing near its upper end.
The bore of the choke is a little less than the diameter of the solid middle part
of the extinguisher disc, so that when the disc rests upon the choke flange of the
extinguisher casing, then the whole of the top is perfectly closed, as the piercings
D

page_text: of the said disc come opposite the solid flange of the casing, and the solid middle of
the said disc comes over the choke or middle opening.
Taking upon the top edge of the casing, above the piercings, and above the
plane of the extinguisher disc, is a ring cap, or a cap with a middle piercing, whose
clearance is greater than the distances between the outsides of the holes in the
disc.
The component and loose parts are kept to the stalk by a cross pin passing
through a hole in the latter.
The extinguisher casing, when elevated, leaves the lower part of the wire gauze
naked, whilst it also works within an open and upright-barred frame, made out of a
single piece of metal by piercing or otherwise, or made out of two or more sections
united together without soldering.
The vertical bars of this frame, which has top and bottom rings, are concaved
and fluted to increase their strength and form guards to the naked gauze, and also
slides for the extinguisher casing, which has opposite trunnion studs directed from
its sides.
The lamp is fitted with an ordinary burner and other accessories common to
miners' safety lamps.
Now assuming that the wick is lighted, and that the lamp is in use, and that fire-
damp is present in the mine in a dangerous quantity, and that its presence and
combustion within the interior of the lamp develops an abnormal heat, which fuses
the soft metal pin or cottar supporting the extinguisher casing and disc, the result
is that the last named parts, being now no longer supported or suspended, fall by
their own weight, and run down the supporting stalk or stem, and cover up the
sides and top of the wire gauze, and shuts off air for supporting combustion from
the lamp.
The extinguisher casing also forms an auxiliary shield as a preventative against
the wire gauze being choked by the coal dust suspended in the air passing to the
lamp for supporting combustion therein.
Dated this 11th dev of July 1802
WILLIAM SANDBROOK,
By Henry Skerrett,
Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Miners' Safety Lamps.
I, WILLIAM SANDBROOK, of Ebbw Vale, in the County of Monmouth,
Ironmonger, 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 :-
This invention relates to improvements in the construction and arrangement of
the parts of miners' safety lamps, and is an improvement upon, or an amplification
of the inventions described and represented in the Specifications of two several
Letters Patent granted to William John Clapp and the present Applicant and dated
respectively the 3rd day of June 1885 No. 6727 and the 4th day of March 1886
No. 3092.
My present invention relates in the one part, to the extinguisher means of the
lamp in another part, to the automatic releasing of the said extinguisher part; in
a further part, to the upper and open frame part, and in a still further part, to a
duplex lock, whereby the case or shield part is locked to the lamp in common with
the oil tank or base part.
The lower part of the lamp is made up of four component and primary parts
consisting of an oil tank forming the base, surmounted by a vertically barred frame,
with an outside-screwed terminal flange, upon which an inside screw at the mouth

page_text: entrance to the case or shield takes, and affixes the said case or shield to the said
lower part and prevents the ingress of coal dust or other foreign matter to the interior
of the lamp.
Located within the barred frame is a short glass cylinder, with the lower part
resting upon the base, and with the upper part coming within the interior of the
screwed ring at the summits of the bars, one of which is loose and sliding and to a
lower extension of which, an arm or loop is jointed, and which lever has a gate or
long slot through it, which takes over a staple plate or eyed plate fixed to the
lamp, and which staple plate, at the fore part of its top edge, constitutes the
fulcrum about which the said lever turns as a centre of motion, whereby the said
loose bar is slid upwards, and its upper end made to engage with a catch
snug or snugs at the mouth entrance to the case or shield to be locked, so that
by passing the slotted lever over the staple plate for locking the body part of the
lamp to its base, the casing or shield is also and at the same time locked to the
lamp.
I
Disposed or located above the lower part of the body of the lamp, and in the same
axial line as the glazing, and above the outside wormed flange as aforesaid, is an
upright cylinder of wire gauze, connected at its lower end to the said lower part, whilst
its upper end has a top, also of wire gauze, upon which a perforated disc, having an
upright stalk or stem proceeding from its middle rests.
Surrounding the upper portion of the said wire gauze cylinder is an extinguisher
casing, of a greater length or depth than the gauze itself, and which extinguisher
casing is normally suspended about half-way up the wire gauze, or at a suitable
distance from its bottom, by the aforesaid stalk or stem through the medium or
intervention of an extinguisher disc, perforated near its edges, and closed at its
middle, and with,the said middle part resting upon a fusible peg or cottar, passing
through the upper end of the stalk.
The extinguisher casing has at its upper end, side piercings, and immediately
below the said side piercings is an inwardly directed flange, which semi-chokes or
contracts the inside of the said extinguisher casing near its upper end.
The bore of the choke is a little less than the diameter of the solid middle part
of the extinguisher disc, so that when the disc rests upon the choke flange of the
extinguisher casing, then the whole of the top is perfectly closed as the piercings of
the said disc come opposite the solid flange of the casing and the solid middle of the
said disc comes over the choke or middle opening.
Taking upon the top edge of the casing, above the piercings, and above the plane
of the extinguisher disc, is a ring crown or a cap with a middle piercing.
The component and loose parts are kept to the stalk by a cross pin passing through
a hole in the latter.
The extinguisher casing, when elevated, leaves the lower part of the wire gauze
naked, whilst it also works within an open and upright-barred frame, made out of a
single piece of metal by piercing or otherwise, or made out of two or more sections
united together without soldering.
The vertical bars of this frame, which has top and bottom rings, are concaved or
fluted to increase their strength and form guards to the naked gauze, and also
slides for the extinguisher casing, which has opposite trunnion studs directed from
its sides.
The lamp is fitted with an ordinary burner and other accessories common to
miners' safety lamps.
Now assuming that the wick is lighted, and that the lamp is in use, and that
fire-damp is present in the mine in a dangerous quantity, and that its presence and
combustion within the interior of the lamp develops an abnormal heat, which fuses
the soft metal pin or cottar supporting the extinguisher casing and disc, the result
is that the last-named parts, being now no longer supported or suspended, fall by
their own weight or are assisted in falling by a spring and run down the supporting
stalk or stem, and cover up the sides and top of the wire gauze, and shut off air for
supporting combustion from the lamp.

page_text: The extinguisher casing also forms an auxiliary shield as a preventative against
the wire gauze being choked by the coal dust suspended in the air passing to the
lamp for supporting combustion therein.
Figure 1 of the accompanying drawings represents, in longitudinal vertical
section, a miners' safety lamp constructed, arranged and provided with improve-
ments made according to my invention. The said figure shows the parts of the
lamp in the positions which they normally assume when the said lamp is in use.
Figure 2 represents a like. sectional view as Figure 1, but with the lamp
extinguished by the dropping down of the extinguisher casing consequent upon the
same being released through the fusing of the lower cottar by which the said
extinguisher casing is upheld and normally supported when in use.
Figure 3 represents a horizontal cross section of the upper part of the lamp, upon
the dotted lines A B Figure 1, looking upwards.
Figure 4 represents a horizontal section of the middle part of the lamp upon the
dotted lines CD Figure 1, showing the supports of the guide frame.
Figure 5 represents a section of a portion of the lower part of the lamp showing
the means of locking the outer casing to the inner frame.
Figure 6 represents a section of the extinguisher casing separately and Figure 7
represents the movable crown and its supporting means separately.
Figure 8 represents an inverted plan of the covering case or sheath.
a is an oil tank, (which is preferably unspillable) forming the base to the lamp,
which base is surmounted by a vertically barred frame b, having at its summit, an
outside-screwed flange b², upon which the inside-screwed mouth c², of the shield or
covering c, takes, which covering is locked to the said frame b, by the end 2, of a
sliding bar-bolt d, taking through the eye b³, of the flange b2, and between one or
other of the snugs c³, arranged around the inner circumference of the said mouth of
the cover or shield c.
Located within the frame b, is a short glass cylinder e, with its lower edge resting
upon the upper part al, of the base a, and with its upper part coming within the
inside boundary edge of the ring or flange 62, of the barred frame b.
The loose and sliding bar-bolt d, is jointed at d', to a loop or slotted arm d³,
having a gate or slot d, through it, which takes over a staple plate. f, carried
upon the side of the oil tank. This staple is curved and the lower part f², of it
forms a fulcrum or inclined plane against which the inner part d', of the gate or
opening, impinges, on the said arm or loop being pressed down, and by it, the
bolt rod d, is automatically shot upwards, and the end extremity d², brought
between the snugs c³, projecting inwardly from the inner circumference of the
mouth of the shield or cover c, thereby preventing the same from being rotated and
locking the cover of the lamp to the lower part.
Located above the lower part of the body of the lamp as aforesaid, and directed
in the same axial line as the glazing, and also coming above the outside wormed
flange of the barred frame, as aforesaid, is a wire gauze cylinder or chimney,
with its lower and flanged end g², resting upon the top side of a prepared felt
washer located upon the top edge of the circular glazing e.
The gauze chimney or cylinder is closed at top, and has resting upon the outside
of it, a perforated foot i, having an upright stalk or stem 2, directed from its
middle, fitted or provided with fusible cross cottars or pins k, k², (the latter of
which may be a non-fusible one) between which, a movable and pierced crown m²,
of an extinguisher casing m, having a choked inside part m', is fitted.
This stalk, forms a prop for supporting both the extinguisher casing m, and
also the loose crown m², which is flanged at m³, and by means of which the
casing m.
is upheld by the same coming upon the underside of the overhanging
flange m of the casing m.
Now the extinguisher casing m, is open at bottom at m³, and has at the upper
end, side piercings me, and a top piercing m', which, when in the position represented
in Figure 1, come coincident with the flange piercings m", of the flange m³, of the
When the fusible piug k, has been melted by abnormal heat in the
crown m².

page_text: interior of the lamp, then the loose crown runs down the stalk 2, and falls upom
the solid flange m', of the choked part of the extinguisher and at the same time,.
both the extinguisher casing and crown (which latter is a greater normal length
than the naked part of the gauze) run down the stem until the flange m³, comes.
upon the closed end of the gauze or upon the perforated foot i, and so hood over
the said gauze and cut off air froin the lamp, hence the same is extinguished.
Surrounding the lower part of the extinguisher and coming between the said
lower part and the outer casing or shield c, is a pierced and barred frame n, (see
Figure 9) made from a blank of sheet metal and having a continuous solid ring-
part, at its upper end, concaved bars ², and base n³, circumferentially embracing
an annular bearing or bed, which is an upward extension of the annular flange. 62,.
upon which bed or bearing, a prepared asbestos or felt washer o, comes, upon
which the edge of the mouth of the extinguisher casing seats itself when the
lamp is extinguished.
The bars, are transversely concaved to impart rigidity and strength to them,.
whilst the extinguisher is loosely connected to the pierced frame n, by studs m³,
standing away from the opposite sides of the walls of the extinguisher m. Before
the pierced blank Figure 9 is turned up, the bars n², are channelled or concaved
and the upper part shaped and then the blank is turned up and the meeting ends
united by the one being folded over the other as marked n, see Figure 4.
Located between the movable crown m2, and the inside crown c*, of the
casing e, is a coiled spring p, designed for the purpose of assisting the bringing
down of the extinguisher and its loose crown. It is understood that this
spring is only an auxiliary to the extinguisher in assisting the taking of the
extinguishing parts home on the fusible cottar or pin k, which keeps the parts
suspended, melting.
The lamp is also provided with a burner 7, and other accessory fittings common
to safety lamps.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
First. In a miners' safety lamp having a detachable and falling extinguisher
casing released by the fusion of a fusible cottar, supporting the said extinguisher
casing through the intervention of a fusible cottar by or from the upper end of an
upright. stalk or stem resting upon the top-side closed end of the gauze chimney,
over which the extinguisher normally partly comes when the lamp is in general
use, substantially as described and set forth.
Secondly. In a miners' safety lamp having a detachable and falling extinguisher
casing released by the fusion of a fusible cottar, making the said casing of two
component parts, i, a loose and falling crown part and a body part with an inside
choke or an inside annular flange near its upper end, substantially as and for the
purpose as described and set forth.
Thirdly. In a miners' safety lamp having a detachable and falling extinguisher
casing released by the fusion of a fusible cottar, making the said casing of two
component parts, viz., a loose crown part and a body part with an inside choke,
and with the said body part supported by the crown through the medium of a
fusible cottar or pin directed through the upper part of an upright stalk supported
by the top of a gauze chimney, substantially as described and set forth.
Fourthly. In a miners' safety lamp having a detachable and falling extinguisher
casing released by the fusion of a fusible cottar, the combination with the com-
ponent parts of the lamp, of a pierced and barred frame surrounding the upper
part of the gauze chimney and the lower part of the extinguisher casing when the
said casing is held in its non-acting position, substantially as and for the purpose
as described and set forth.
Fifthly. In the pierced and barred frames of miners' safety lamps as referred to.
in the preceding claim, making the same from a single blank of sheet metal, with

page_text: the edges united together without soldering by the overlapping of the one edge
over the other, substantially as described and set forth.
Sixthly. In the pierced and. barred frames of miners' safety lamps, cross-
concaving or cross channelling or longitudinally fluting the sheet metal bars of the
said framing, whereby the strength of the said bars is increased, substantially as
described and set forth.
Seventhly. In a miners' safety lamp having a detachable and falling extinguisher
casing released by the fusion of a fusible cottar, the combination with the
extinguisher casing m, m2, the pierced and barred frame n, the gauze chimney g;
and extinguisher supporting means i, i², k, and auxiliary spring p, of an outer shield
or casing. c, substantially, as described and set forth.
Eighthly. In miners' safety lamps having detachable and falling extinguisher
casings released by the fusion of fusible cottars, the general construction, arrange-
ment and combination of the parts above the glazing, substantially as described
and set forth.
Ninthly. In miners' safety lamps having detachable and falling extinguisher
casings released by the fusion of fusible cottars, the general construction, arrange-
ment and combination of the whole of the parts, less the locking means, substantially
as described and set forth.
Tenthly. In miners' safety lamps, locking the upper part of a lamp to the lower
part (to prevent the opening of the same), by a sliding rod or bar jointed at one
end to a loop-shaped arın adapted to take over the staple plate and when pressed
home over the said plate, to automatically lock the said lamp by the unjointed end
taking between snugs or equivalents located around the inner circumference of the
mouth of the outer shield or casing, substantially as described and set forth.
1
100
WILLIAM SANDBROOK,
By Henry Skerrett,
6, Livery Street, Birmingham, Agent for Applicant.