IMPROVE- MENTS IN MINERS' SAFETY LAMPS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Thomas Thomas at the
Office of the Commissioners of Patents on the 9th November 1882.
THOMAS THOMAS of Ynishir in the County of Glamorgan, Coal Miner, "IMPROVE-
MENTS IN MINERS' SAFETY LAMPS."
This Invention which relates to improvements in miners' safety lamps, is
designed, firstly, to reduce the risk of explosion, by surrounding the gauze with
shields to break the force of the currents of air which ventilate mines and which
are liable to contain explosive gas. Secondly, this invention is designed to make
miners' lamps self locking, and, thirdly, it is designed to extinguish such lamps
simultaneously with the act of opening them.
The first part of this invention is more especially applicable to that class of lamps
known as the Clanny lamp and to lamps which bear a resemblance to the same.
It consists in the employment of two cylindrical shields surrounding the gauze and
preferably arranged on the outside of the pillars of the lamp. The upper shield
extends from the top of the lamp down to a desired point near the ring which
forms the junction between the gauze and the glass, where the said shield is turned
at right angles and forms a partial joint with the gauze. The portion of gauze
intervening between the bottom of the shield and the ring, is protected from direct
exposure to the velocity of air currents by a second cylindrical shield which extends
upwards for that purpose from the ring and, being of larger diameter, it overlaps
the upper shield which protects the upper portion of the gauze in like manner..
The lower shield having an open mouth, free access of air to the lamp is obtained,
and the area of the top of the gauze is regulated to allow for the proper exit of the
products of combustion.
The second part of this Invention consists in forming the lock of the lamp of a
small hollow box fixed to the bottom portion of the lamp case and containing a
catch or button, to the upper side of which is fitted a horizontal spring. The
spring catch or button extends into the lamp bottom or oil vessel when screwed
Pavice 6d1

page_text: home, and the lamp being thus locked, can be opened only by a V shaped, or other
special form of, key.
The third part of my invention consists in the employment of a cylinder or tube
open at each end and pierced to permit the passage of the pricker for the regulation
of the wick in the usual way. This cylinder, the ends of which are turned outwards
in the form of flanges, is made to slide vertically over the burner, and when the
lamp bottom is being screwed home, the flange on the upper end of the cylinder
comes into contact with the ends of two or more arms which are thereby made to
pivot on the hinges by which they are secured, sufficiently to permit the cylinder
to rise into place, when the said arms resume their normal position. When the
lamp bottom is unscrewed, the cylinder is thus retained in the case, and the light
is thereby extinguished as it is being withdrawn.
•
The lower flange of the cylinder is notched to provide for the pricker, and thus
the extinguishing cylinder, when in place, maintains its position with reference to
__ the burner.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Thomas in the Great Seal Patent Office on the 9th May
1883.
THOMAS THOMAS of Ynishir in the County of Glamorgan, Coal Miner. IMPROVE-
MENTS IN MINERS' SAFETY LAMPS.
My said invention which relates to improvements in miners' safety lamps is
designed, firstly, to reduce the risk of explosion, by surrounding the gauze with
shields to break the force of the currents of air which ventilate mines and which
are liable to contain explosive gases.
Secondly, my invention is designed to make miners' lamps self locking, and,
thirdly, it is designed to extinguish such lamps simultaneously with the act of
opening them.
The first part of my said invention is more especially applicable to that class of
lamps known as "Clanny" lamps and to lamps bearing a resemblanco thereto. It
consists in the employment of two cylindrical shields surrounding the gauze, which
shields may be placed either around the pillars of the lamp, or between them and
the gauze.
One of the shields extends from towards the top of the lamp
downwards to a point overlapped by the top of the other shield which protects the
portion of gauze intervening between the bottom of the upper shield and the ring
at which the gauze and glass meet, from direct exposure to the velocity of air
currents. The upper shield protects the upper gauze in like manner. The lower
shield being open at the top, free access of air to the lamp is provided.
The second part of this invention consists in forming the lock in a small hollow
box fixed to the bottom of the lamp case and containing a tongue or tumbler having
a stud or button formed on its underside. When the oil vessel is screwed into
place in the lamp, the stud or button is forced, by the action of a spring bearing
on the upper side of the tongue or tumbler, into a recess provided for its reception
in the oil vessel to which the lamp case thus becomes locked. The lamp can be
opened only by a V shaped, or other special form of, key.
The third part of my invention consists in the employment of a cylindrical or
conical thimble opened at each end and pierced to permit the insertion of the
The said thimble slides
pricker for adjusting the wick in the usual manner.
vertically over the burner and, when the lamp bottom is being screwed up to close
the lamp, the flange or rim on the upper end of the thimble comes into contact with
the inner ends of two or more arms extending towards the burner, and the said
arms are thereby tilted on the hinges by which they are secured sufficiently to
permit the thimble to rise into place. After the rim of the thimble has passed
beyond them, the arms resume their normal position. The arms may consist of
flat pieces secured firmly in place, instead of being hinged, and of sufficient
elasticity to resume their normal position after the rim of the thimble has been-
passed up between them. As the lamp bottom or oil vessel is unscrewed, the
thimble is retained in the case by the ends of the arms aforesaid, and the flame of
the light is thereby extinguished while being withdrawn.
And in order that my said invention may be properly understood and the mode
or manner in which the same may be used or practically carried into effect, I now
proceed more particularly to describe the same with reference to the accompanying
sheet of drawings and the figures and letters marked thereon.
Fig: 1 on the accompanying sheet of drawings represents a view, partly in
elevation and partly in vertical section, of a lamp constructed in accordance with
my invention. The upper shield A, embracing the upper gauze compartment a,
extends from towards the top of the lamp down to a point overlapped by the lower
shield B screwed to the ring R at which the glass G and the gauze b meet. The
upper gauze compartment a is thus sufficiently protected from direct exposure to

page_text: the velocity of currents by the cylindrical shield A, and the lower gauze compart-
ment b is likewise protected by the shield B. The latter is open at the top to
permit free access of air to the lamp.
C
The self locking device, forming part of my improvements, consists of a tumbler
or tongue c pivotted at e in the box d and having a stud or button f formed on the
underside at the end opposite to the pivot e. A flat spring g tends to exert a
downward pressure on the tumbler c whereby, when the oil vessel D carrying the
burner and wick is screwed into place, the stud or button is maintained in a
recess formed in the oil vessel D to receive the same, and the lamp thus becomes
locked. On the application of a V shaped key to the pivote to overcome the
downward pressure of the spring g, the projection c¹ on the tumbler c, being raised,
indicates the withdrawal of the stud or button f from the recess aforesaid. The oil
vessel D may then be unscrewed. While, by the bearing of the stud or button f
on the underside of the lamp case, the projection c¹ is kept raised, an indication is
afforded that the lamp is not locked.
-
That part of my invention which relates to the extinguishing of the flame as the
lamp is opened, consists in the employment of a cylindrical or conical thimble o
slotted to admit of the insertion of the pricker p correspondingly with the burner-m
secured in place in the usual manner. As the oil vessel D is being screwed up into
position to close the lamp, the rim 8 of the thimble o comes into contact with the
inner ends of the arins 7. r. which are thereby forced outwards sufficiently to permit
the passage of the rims. By their elasticity the said arms r. r. then resume their
normal position and embrace the thimble o below the rims as seen at Fig. 1 and also at
Fig. 2 which is a transverse sectional view taken immediately above the burner m.
When the oil vessel 1) is unscrewed the cylinder or thimble o is retained in the case
by the arms and the flame becomes-extinguished as the burner is withdrawn
through-the thimble. Two springs tie upper-ends-of which tend to incline
towards each other are fixed in the thimble-o-and assist in extinguishing the flame.
A bar or rod pierced with a succession of holes to hold matches or match-heads
may be made to slide vertically in a barrel or tube, extending upwards through tho
oil vessel, in such manner that at a point opposite the top of the burner the
matches, by impinging against the serrated face of a spring or against any other
suitable face, iguite and light the lamp wick. The lamp may thus be lit without
being opened.
Having now described and particularly ascertained the nature of my said
invention and the mode or manner in which the same is or may be used or
practically carried into effect, I claim as the invention secured to be by the berein-
before in part recited Letters Patent.-
1, The employment in miners' safety lamps of the shields surrounding the
gauze, one of which shields overlaps the other as hereinbefore described and for the
purpose set forth.
2nd, The means whereby the oil vessel carrying the burner becomes locked to
that part of the lamp above it at such time as the oil vessel is secured. in place,
substantially as described and shown.
3rd, The means whereby the act of opening the lamp causes the flame to be
extinguished substantially as described and shown.
In witness whereof I the said Thomas Thomas have hereunto set my hand
and seal this eighth day of May in the year of Our Lord one thousand
sicht hunded and night th
THOMAS THOMAS (L.S.)