Year: 1887

page_text: Date of Application, 8th Dec., 1887
Specification Accepted, 13th Jan.. 1888
I, LORENTZ ALBERT GROTH of No. 5 Crosby Hall Chambers in the City of
London, Civil Engineer, as a communication to me from abroad by Jules Lotineaux,
Manufacturer, of No. 15 Impasse Ménilmontaut, in the City of Paris 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:
Reference being had to Figures 1, 2, 3, 4 and 5 of the sheet of drawings accom-
panying Figure 1 is a vertical section of the lamp, duly closed; figure 2 is a plan
view of the lock of the lamp, its bottom plate being partly removed, in order to shew
the inner mechanism; figures 3 and 4 shew the key; and figure 5 a plan view of the
collar A¹.
This invention relates to improvements in safety lamps for miners, the principal
features of which are the admittance of the air under the wick, by means of a special
organ, in order to prevent explosion due in the presence of fire damp; the arrange-
ment of a double cap of wire-gauze in order to prevent the admittance of air or fire-
damp through the top of the lamp; and a special lock, preventing the miner from
opening the lamp. a is a common oil reservoir, the bottom of which can be turned
round by means of a pivot k and an arın a. This arm is retained in the position
shewn on the drawings by means of the spring
The left end of said arm is
connected with the pin a', traversing the oil reservoir, which can thus be raised or
lowered according to the movements of the said arm.
The hollow foot of the lamp is on its inner side provided with a border n n, the
object of which is to support the special lock, as will be mentioned later on.
The wick, not shewn on the drawings, is moved in the usual way, by means of
wheel i, rod and knob j.
The upper part of the oil reservoir is provided with a kind of basket or hoop h,
consisting of the part of wire-gauze, under which is placed a perforated circular
gallery The collar h¹ rests on a projecting edge of the hoop hand at a certain
distance from the wire-gauze, leaving a passage for the wick, through an oblong
opening corresponding with the empty circular chamber in the bottom of part 2;
this empty chamber does not however communicate with the exterior, as the ring,
which limits it, encloses a circular socket, of the same hight and diameter as the top-
hole-plug for admitting the oil, and whereby the exterior atmospher cannot

page_text: communicate with the interior of the lamp, without traversing the wire-gauze h². lis
the glass, resting on the collar h¹ fis the chimney, extending through a collar g of
wire-gauze, which rests upon the upper part of the glass. e is a double cap of wire-
gauze, which terminates in an annular rim, which encloses the glass and rests on the
collar g.
c is a case of sheet iron enclosing a part of the cap e, and resting on a
small circular projecture of the annular rim, which terminates the cap. This case has
for object to protect the cap and to increase the draught. a² constitutes the vertical
pillars of the lamp, and consists of a number of pieces, kept together partly by an
iron ring a³, which rests on the inner projecture of the case c, and partly by a ring a',
screwed on to the oil recevoir a. The horizontal part of this ring possesses sockets
on its inner side, in one of which the top of the pin a enters, when the said ring
is screwed down entirely, its moving is thus rendered impossible, unless the pin a' is
forced down by means of the arm a³. In order to prevent this, a special lock is
employed, and shown in figs. 2. 3. 4. This lock consists of a box, formed of two
circular plates, fastened together, between which is left room sufficient to enclose the
mechanism. This mechanism consists of certain number of rotating bolts m m³ (three
shewn on the drawings), each provided with a spring m², pressing on the part m.
These bolts are made to project through openings in the periphery of the box, q, s, by
introducing the key o ol (fig. 3, 4), and turning it from right to left; the projecting
parts will then push the bolts mm² round their respective axis, the part m
entering the box. In this state, the lock is applied to the circular ring n n, and
by then withdrawing the key, the springs m² are liberated, thereby repushing the
heads m of the bolts, which then will rest on the upper face of the circular ring n n,
whilst the inner face of the bottom plate of the box will lean against the lower part
of the ring n n. The lamp is thus entirely and securely closed, and impossible to
open it without the key, which is not left with the miner. The keyhole is covered by
a special plate p, hinged on by p³, or in
other suitable way.
any
The action of the lamp, when fire damp is at hand, is as follows.
The flame ascends on the fire damp approaching, and indicates to the miner, that
danger is at hand; he then lowers the wick, and the flame is, so to say, fed by the
fire damp; when this arrives in excess, the flame extinguishes suddenly, as well as all
the flames of fire damp, remaining in the lamp.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, 1 declare that what I
claim is
10) The loop h h² h³ with collar h¹.
20 The double cape of wire gauze, partly enclosed in a cap c.
30 The pin a in conjunction with the ring a', arm a and spring r.
4°) The lock and key, as shewn in fig. 2. 3. 4; substantially as hereinbefore
described and illustrated in the drawings hereto annexed.
Dated this 8th day of December 1887