IMPROVED APPARATUS FOR GENERATING A CURRENT OF ELECTRICITY FOR DISCHARGING FUSES FOR MINING AND OTHER PURPOSES
Year: 1871

page_text: LETTERS PATENT to Edward John Cowling Welch, of Eden Street,
Hampstead Road, in the County of Middlesex, Engineer, for the
Invention of "IMPROVED APPARATUS FOR GENERATING A CURRENT OF
ELECTRICITY FOR DISCHARGING FUSES FOR MINING AND OTHER PURPOSES."
ealed the 19th September 1871, and dated the 22nd March 1871.
PROVISIONAL SPECIFICATION left by the said Edward John Cowling
Welch at the Office of the Commissioners of Patents, with his
Petition, on the 22nd March 1871.
I, EDWARD JOHN COWLING WELCH, of Eden Street, Hampstead Road,
in the County of Middlesex, Engineer, do hereby declare the nature of
the said Invention for "IMPROVED APPARATUS FOR GENERATING A CURRENT
OF ELECTRICITY FOR DISCHARGING FUSES FOR MINING AND OTHER PURPOSES," to
be as follows:—
This apparatus consists of a brass or other metallic frame carrying
a permanent magnet, to the ends of which magnet are attached soft
iron cores upon which coils of insulated wire are placed. An armature

page_text: of soft iron is placed against the ends of the soft iron cores, and through
the centre of the armature and at right angles thereto is fixed a round
spindle, which is carried through suitable bearings. On this spindle
is fixed a collar, and on the part of the spindle on the side of the collar
furthest from the armature slides freely a metallic weight or ram.
Behind the weight or ram, and between it and one of the bearings
carrying the spindle, is a spiral steel spring just fitting, when fully
open and at rest, between the weight or ram and the bearing when the
weight or ram is close up to the collar on the spindle. Beneath the
spindle and at right angles thereto is placed a metal spindle carrying
a ratchet catch, which takes into a suitable groove in the weight or
ram, such spindle being free to revolve through a portion of a circle.
When the last-mentioned spindle is turned by means of a key adapted
for the purpose it draws back the weight or ram, compressing the spring
between it and the bearing until in a certain position. When the
spring is fully compressed the catch slips out of the groove, and the
weight or ram being impelled by the action of the spring, strikes
against the shoulder and removes the armature from the magnetic
cores, thus inducing a powerful current in the coils. A small lever
urged by a spring lifts a bolt at the back of the spindle, which carries
the armature and prevents its return until (the key being released) the
spindle carrying the catch is returned to its former position by a spring
attached to it for that purpose, and in so returning it lifts, by means
of a small projecting pin, the lever carrying the bolt, when a fine return
spring provided for that purpose sends the armature back to its place
on the magnetic cores ready for another discharge. It is necessary to
cause the circuit between the coils and the wires which lead to the fuse
to be broken exactly when the armature is at a certain distance from
the magnet. This is effected by placing an insulated stop just above
and beyond the armature. In the top of the armature is screwed a steel
pin projecting upwards and at right angles to the magnetic cores, and
which moves with the armature. A small lever is fixed to an adjustable
frame, which frame has a slot for the pin to pass along; and at the side
of the slot the lever is centred and so arranged with a spring that it
shall press against the insulated stop. The lever is so formed that
sliding the adjustable frame backwards or forwards, nearer to or further
from the armature pin, does not cause the lever to turn on the centre.
The inside face of the lever being parallel to the slot at that end where

page_text: the lever presses on the stop, but nearer the centre, it slightly inclines
across the slot, and has a sudden inclination near its centre. When the
armature is at the proper distance from the magnetic cores the pin just
touches the more suddenly inclined part of the lever and removes its
end from the stop, thus cutting off the connection, and as the pin slides
along it only passes smoothly along the lever, as that part which pre-
viously just inclined across the slot is now parallel to it, so that the
lever is not pushed further away than is requisite, just to suddenly
break circuit, and so the spring is not strained, and the pin is not
impeded in its further motion. By connecting the wires in a suitable
manner this arrangement may be made either to break the full circuit
or to simply cut off "short circuit" as may be required.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward John Cowling Welch in the Great Seal
Patent Office on the 22nd September 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
JOHN COWLING WELCH, of Eden Street, Hampstead Road, in the County
of Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of March, in the
year of our Lord One thousand eight hundred and seventy-one, in
the thirty-fourth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Edward John Cowling
Welch, Her special licence that I, the said Edward John Cowling
Welch, my executors, administrators, and assigns, or such others as I,
the said Edward John Cowling Welch, my 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 "IMPROVED APPARATUS FOR GENERATING
À CURRENT OF ELECTRICITY FOR DISCHARGING FUSES FOR MINING AND OTHER PUR-
POSES," upon the condition (amongst others), that I, the said Edward
John Cowling Welch, my executors or administrators, by an instrument

page_text: in writing under my, or their, or one of their hands and seals, 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 Edward John Cowling Welch, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, that is to say :—
My said Invention relates to the construction of apparatus for
generating a current of electricity which is capable of being applied
to discharging fuses for mining, military operations, and other purposes.
The apparatus consists of a brass or other metallic frame carrying a
permanent magnet, to the ends of which magnet are attached soft
iron cores, upon which coils of insulated wire are placed. An armature
of soft iron is placed against the ends of the soft iron cores, and through
the centre of the armature, and at right angles thereto is fixed a spindle
of circular section which is carried through suitable bearings. On this
spindle is fixed a collar, and on that part of the spindle which is on the
side of the collar furthest from the armature a metallic weight or ram
is placed capable of sliding freely thereon. Behind the weight or ram
and between it and one of the bearings carrying the spindle is a spiral
steel spring just fitting, when fully open and at rest, between the
weight or ram and the bearing, when the weight or ram is close up to
the collar on the spindle. Beneath the spindle and at right angles
thereto is placed a metal spindle carrying a ratchet catch, which takes
into a suitable groove in the weight or ram, such spindle being free to
revolve through a portion of a circle. When the last-mentioned spindle
is turned, which operation is effected by means of a key adapted for the
purpose, as will be well understood, it draws back the weight or ram and
compresses the spring between it and the bearing. When the spring is
fully compressed the catch slips out of the groove, and the weight or
ram being impelled by the action of the spring strikes against the
shoulder and removes the armature from the magnetic cores, thus
inducing a powerful current in the coils. A small lever urged by a
spring is so placed as to lift a bolt at the back of the spindle which
carries the armature, and prevents its return until (the key being

page_text: released) the spindle carrying the catch is returned to its former
position by a spring attached to it for that purpose, and in so returning
it lifts by means of a small projecting pin the lever carrying the bolt,
when a fine return spring provided for that purpose sends the armature
back to its place on the magnetic cores ready for another discharge.
It is necessary to cause the circuit between the coils and the wires
which lead to the fuse to be broken exactly when the armature is at a
certain distance from the magnet. This is effected by placing an insu-
lated stop just above and beyond the armature. In the top of the
armature is screwed a steel pin which projects upwards and at right
angles to the magnetic cores, and which moves with the armature. A
small lever is fixed to an adjustable frame, which frame has a slot for
the pin to pass along, and at the side of the slot the lever is centred
and so arranged with a spring that it shall press against the insulated
stop. The lever is so formed that sliding the adjustable frame back.
wards or forwards, nearer to or further from the armature pin does not
cause the lever to turn on the centre, the inside face of the lever being
parallel to the slot at that end where the lever presses on the stop, but
nearer the centre it slightly inclines across the slot and has a sudden
inclination near its centre. When the armature is at the proper distance
from the magnetic cores, the pin just touches the more suddenly inclined
part of the lever and removes its end from the stop, thus cutting off
the connection, and as the pin slides along it only passes smoothly along
the lever, as that part which previously just inclined across the slot is
now parallel to it, so that the lever is not pushed further away than is
requisite suddenly to break circuit, and so the spring is not strained,
and the pin is not impeded in its further motion. By connecting the
wires in a suitable manner, as will be well understood, this arrangement
may be made either to break the full circuit, or to simply cut off " short
circuit" as may be required.
The apparatus before described is enclosed in a box or case having
on the exterior thereof the necessary arrangements for attaching the
conducting wires and for the introduction of the key. The box or case
being securely fastened the mechanism cannot be tampered with, nor
can a discharge be effected except by the use of the proper key.
Having thus described and ascertained the nature of the said Inven-
tion, and in what manner the same is to be performed, I would observe

page_text: in conclusion that what I consider novel and original, and therefore
claim as the Invention secured to me by the said herein-before in part
recited Letters Patent is, the combination and arrangement of parts
and mechanism substantially as and for the purposes herein-before
described and set forth, or any mere modifications thereof.
In witness whereof, I, the said Edward John Cowling Welch, have
hereunto set my hand and seal, the Twenty-first day of Septem-
ber, in the year of our Lord One thousand eight hundred and
seventy-one.
Witness,
EDWARD J. COWLING WELCH. (L.S.)
R. S. MORDAUNT VAUGHAN,
54, Chancery Lane.