IMPROVEMENTS IN SAFETY LAMPS, AND IN APPARATUS
Year: 1858

page_text: LETTERS PATENT to Thomas Robinson, of Manchester, in the County of
Lancaster, Brassfounder, and Heth Ogden, of the same Place, Engineer,
for the Invention of "IMPROVEMENTS IN SAFETY LAMPS, AND IN APPARATUS
Scaled the 7th December 1858, and dated the 9th June 1858.
PROVISIONAL SPECIFICATION left by the said Thomas Robinson and
Heth Ogden at the Office of the Commissioners of Patents, with their
Petition, on the 9th June 1858.
We, THOMAS ROBINSON, of Manchester, in the County of Lancaster, Brass-
founder, and HETH OGDEN, of the same Place, Engineer, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN SAFETY LAMPS, AND IN
APPARATUS CONNECTED THEREWITH," to be as follows:-
Our Invention consists, firstly, in the application of two or more fastenings,
which must be kept back in order to enable the lamp to be opened; thus we
employ three catches, which are forced forward by springs, and must therefore
be simultaneously held back.
Another part of our Invention consists in forming the keys with an interior
or exterior thread, by which they must be screwed on to the catches or locks
in order that the lamp may be opened.
Another part of our Invention consists in apparatus for enabling the duly
appointed person to unlock a lamp fastened according to the first part of our
Invention; this may be thus described :-To a table are adapted the two or

page_text: more keys, in such manner as to be capable of being applied to the lock and
of withdrawing the catches, means' being provided for moving them simul-
taneously or for retaining them consecutively as they are withdrawn. A
particular arrangement we adopt is to mount the keys upon levers capable
of turning upon centres. Within the circle enclosed by these the lamp is
placed, and the keys having been adapted the said levers are turned so as to
withdraw the whole simultaneously.
Another part of our Invention consists in the application to safety lamps of
reflectors formed of enamelled metal.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Robinson and Heth Ogden in the Great Seal Patent
Office on the 9th December 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
ROBINSON, of Manchester, in the County of Lancaster, Brassfounder, and
HETH OGDEN, of the same Place, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of June, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said Thomas Robinson and Heth Ogden, Her especial license that we, the
said Thomas Robinson and Heth Ogden, our executors, administrators, and
assigns, or such others as we, the said Thomas Robinson and Heth Ogden,
our executors, administrators, and assigns, should at any time agree with, and
no others, from time to time and at all times. thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN SAFETY LAMPS,
AND IN APPARATUS CONNECTED THEREWITH," upon the condition, amongst others,
that we, the said Thomas Robinson and Heth Ogden, or some or one of us,
by an instrument in writing under our hands and scals, or under the hand
and seal of one of us, should particularly describe and ascertain, the nature of
the said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Robinson, do hereby declare
the nature of our said Invention, and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement and accompanying Drawing (that is to say):-
The object of the first part of our Invention is to attach the gauze to the
lamp in such a manner that it cannot be removed by any apparatus which
the miner usually has at his disposal, and to effect this end in a simple
manner.
In the accompanying Drawing, Fig. 1 represents the lamp in clevation;
and Fig. 2 is a sectional plan view taken through the locking apparatus,
representing the two parts fastened together. The gauze is shewn at a, and
the lower boss to which it is attached at 6; this boss fits upon the lamp c,
and is provided on its periphery with a series of inclined notches & and
recesses e, the latter of these are for the reception of bolts f, which aro
mounted in sockets attached to the lamp, and are pressed forward by springs g,
but capable of being withdrawn by screwing a key on to their spindles h.
Suppose the
gauze to be separate from the lamp and it is desired to fasten the
two together, the notches & are placed opposite the bolts f, the gauze is then
turned round, so that the bolts are forced back by the inclined sides of the
notches, thus bringing them to bear upon the concentric surface, after which
a further turning of the gauze will bring the recess e opposite to them, and
into which they will then spring, so as to secure the lamp, as shewn in Fig. 2.
The two parts being now fixed together in three places, it is evident that the
spring bolts must be held back simultaneously before they can be separated,
and to do this, apparatus of a different character from ordinary keys must be
employed, in addition to which any instrument to be employed must be tapped
with a thread corresponding to that upon the spindles h. Fig. 3 represents
in plan view the arrangement we employ for unlocking these lamps. Upon
a metal block k are mounted three bell-crank levers 1, so as to turn upon
centre pins m; within slots formed in these levers are the keys n, the ends
thereof being tapped with threads corresponding to those upon the spindles h
of the bolts f, and the said slots are sufficiently long to allow a motion of the
keys for adjustment of position; the bell-crank levers are connected together
by rods o, and to the centre of one of them is attached a handle p.
The apparatus above described is kept by a person appointed for the
purpose, and upon a lamp being brought to him to be unlocked, he places it
in the situation A, the keys are then moved inward and screwed upon the
spindles h, when the handle p being turned, the bolts f will be simultaneously
withdrawn and held back, so as to allow of the gauze being removed.
The next part of our Invention relates to reflectors used with safety lamps.
For this purpose we make them of sheet metal and coat the surface with

page_text: enamel, after the usual manner as applied to other purposes. These reflectors
may be adapted to the lamps in the same manner as those now in use.
In reference to the first part of our Invention, we would observe that although
we have shown three fastenings for the lamp, yet we do not confine ourselves
thereto, as two or a greater number than three may be employed if desired;
nor do we confine ourselves to the mechanical arrangements shewn and
described for effecting such fastening, as many modifications may be made
thereon. We would also observe that although we have described a certain
unlocking apparatus as part of our Invention, yet we do not limit ourselves to
its use, only combined with the other part of our Invention; that which wo
claim as secured to us under the above in part recited Letters Patent
being,-
Firstly, the use of two or more fastenings, which must be held back simul-
taneously to allow the gauge to be removed:
Secondly, the use of keys acting by screw threads for unlocking safety
lamps, whether one or more fastenings be employed.
Thirdly, an apparatus for unlocking, described at Fig. 3, whereby two or
more keys are inade to act simultaneously.
Fourthly, the use of enamelled metal reflectors for safety lamps.
In witness whereof, I, the said Thomas Robinson, have hereunto set my
hand and seal, this Eighth day of December, in the year of our
Lord One thousand eight hundred and fifty-eight.
THOMAS ROBINSON. (L.S.)