Improvements in or connected with Safety Fuses.
Year: 1896

page_text: Date of Application, 5th May, 1896
Complete Specification Left, 5th Feb., :897-Accepted, 5th May, 1897
PROVISIONAL SPECIFICATION.
Improvements in or connected with Safety Fuses.
I HERMANN HOHENDAHL, Managing Director, of Camen, Westfalea, in the
Empire of Germany, do hereby declare the nature of this invention to be as
follows:-
This invention for improvements in or connected with safety fuses consists of
two main parts, an igniting device and pincers.
In the annexed drawing Fig. 1 is a longitudinal section on the line Y-Y;
Fig. 2 a view of one half of the pincers with section of rotating stud f³, and Fig. 3
a cross section through x-x of Fig. 1.
The igniting device A is formed of the following parts; the chamber piece a,
the closing piece b furnished with a bayonet joint, the striking bolt c which
carries in its prolongation the handle d and the trigger d', and lastly the spiral
spring e.
The pincers consist of the two gripping parts and the bolt f³ with a nut.
When pressed together they form in their interior several cylindrical bores; the
middle one for receiving and clamping the match cord and priming cap by means
of the projections; the adjoining ones, serving for the discharge of the powder
gases, carry the cutting device at their end.
Into the open pincers I so place the match cord with the priming cap put on that
the front of the cap will touch that of the igniting device, the pincers being then
closed by pressing them together.
In the first place the igniting device is put under tension by pulling out the
striking bolt and engaging the trigger; and then, the lower handle of the pincers
being held by three fingers of the right hand and the upper handle by the thumb,
the trigger can be removed by means of the forefinger and the firing can take
place.
The apparatus serves for igniting the charges in fire-damp mines, is very handy
and acts with absolute certainty; the cap cannot possibly fall out, and the
emission of sparks endangering the life of the workman is entirely obviated.
Dated this 5th day of Mar 1896.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.
Improvements in or connected with Safety Fuses.
1, HERMANN HOHENDAHL, Managing Director, of Camen, Westphalia, in the
Empire of Germany, 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 for improvements in or connected with safety fuses consists of
two main parts, an igniting device and pincers. The igniting device consists of a
chamber piece, a closing piece furnished with a bayonet joint, a striking bolt which
carries in its prolongation a handle and trigger and a spiral spring. The pincers
are formed of two gripping parts pivotally connected.

page_text: In the accompanying sheet of illustrative drawings:
Fig. 1 is a sectional elevation of an igniting device and pincers constructed
according to this invention.
Fig. 2 is an elevation showing the pincers in an open position. Fig. 3 is a plan
of the same, and Figs. 4 and 5 are elevations showing pincers of modified
construction.
The igniter E is composed of the chamber piece a the cover piece b provided
with a bayonet. fastening, and the striking bolt c, which carries on its projection
the spring holder d and the holding down piece e, and finally the spring f. The
pincers Z consist of the two handles g' and g², the rotating bolt h and the jaws i¹
and which are provided with several horings kkk and carry the cutting
apparatus 12. The central boring k¹ receives the fuse and cap which are
clamped between the projections m, the side borings 2k serve to lead the powder
gases away.
The fuse is cut off to the length required by the cutters and with the cap
fitted on is inserted in the open pincers in such manner that the front surface of the
cap rests on that of the igniter, the pincers are then closed and the igniter is put
in tension by drawing out the striking bolt c and inserting of the holding down
piece e. In use the tool is held by gripping the handle g¹ with three fingers of the
right hand and the handle g2 by the thumb, the holding down piece e is then
released by the index finger and ignition caused.
Fig. 4 shows an arrangement for automatically putting the spring f in tension.
A sliders is jointedly connected by a link t to the jaw 2 on which the igniter E is
fitted, so that in opening the pliers the slider s pushes back the striking bolt c with
the spring (shown dotted) and thus put the igniter E in tension.
A further form of construction of the tension arrangement is shown in Fig. 5.
The back end of the striking bolt c is bent up at right angles, provided with a
knob, and runs in a slot m' of the chamber piece a and cover piece b. By pulling
the knob, whereby the projection moves in the slot m', the spring is put in
tension and by rotating the projection sideways (shown dotted) it is kept in this
position.
The apparatus serves for the ignition of charges in mining, it is convenient and
acts with absolute certainty as the cap cannot fall out, and spark-flying, so
dangerous to the lives of the workmen, is prevented.
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 [
claim is :-
1. A safety igniter E characterised by its combination with pincers Z for cutting
off the fuse and by the arrangement of continuous channels k k and projections m,
the former for the escape of the powder gases without danger, and the latter
acting as clamps for the fuse and the caps.
2. In the apparatus described under Claim 1 the arrangement of a spring
apparatus characterised by the link t and the sliders whereby the spring fis
automatically put in tension by opening the pliers..
3. In the apparatus described under Claim 1 the arrangement of a spring
apparatus characterised by the right angled bent projecting piece of the striking
bolt e running in the slot m, so that by the drawing back and side rotation thereof
the spring is put in tension.
4. The improvements in or connected with safety fuses substantially as described
with reference to the drawings.
Dated this 5th day of January 1897.
WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.