Improvements in and connected with Fuses for Electrical Cut Outs.
Year: 1896

page_text: Date of Application, 31st Jan., 1896
Complete Specification Left, 28th Oct., 1896-Accepted, 16th Jan., 1897
Improvements in and connected with Fuses for Electrical
Cut Outs.
I, HUGO HIRST of 71 Queen Victoria Street in the City and County of London,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to certain improvements in fuses for electrical cut outs, and
has for its object the prevention of the formation of an electric arc when the fuse
breaks the circuit.
In carrying my invention into effect I interweave the fusible metal into and
through an insulating and proferably refractory substance or material such for
instance as asbestos, and in such a manner as to stagger the fusible circuit, the
irregular course thereby taken by the fuse wire or its equivalent in conjunction
with the insulating substance breaks down or prevents the formation of an arc when
the fuse is melted by an excess of current.
I do not confine myself to the use of any special fusible metal or insulating
medium, the essential features of my invention being the interweaving or stitching
of the fusible metal or its equivalent into or through the said insulating medium or
substance in an irregular direction and made so as to be readily adapted to various
forms or types of cut outs.
1
1800
FREDK. WALKER,
Fellow of the Society of Patent Agents,
88 Queen Victoria Street, Agent for the Applicant
Improvements in and connected with Fuses for Electrical
Cut Outs.
I, HUGO HIRST of 71 Queen Victoria Street, in the City and County of London,
Electrical Engineer 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 :-
My invention relates to certain improvements in fuses for electrical cut-outs,
and lins for its objects the prevention of the formation of an electric arc when the
fuse is ruptured or breaks the circuit.
In order that my invention may be the better understood, I have appended
the accompanying sheet of drawings, in which
Figure 1 is a plan of a threaded fuse, and Figure 1A is a section thereof.
Figure 2 is a plan of a modification thereof, and Figure 2A is a section thereof,
and Figure 3 is an elevation of another modification and Figure 3ª is a section
thereaf

page_text: Figures 4 and 5 show other methods of interweaving according to my
invention, and Figure 6 is an elevation showing a modification with contact pieces
and a rigid bridge, and Figure 7 is an elevation of an alternative device with
slotted contact pieces.
Figure 8 is a modification of the device shown by Figure 6 with multiple fusible
conductors.
Figure 9 is a modification in which the fusible conductor has a free end.
Figure 10 is a plau view, and Figure 10 a sectional view of a fusible conductor
carried in a rigid base with metallic enntact pieces.
Figure 11 shows a modification of the foregoing with open slots in the base.
Figure 12 is an elevation of a fuse having a handle and contact pieces, and
Figure 13 is an elevation of a modification thereof.
Similar letters of reference indicate corresponding parts throughout the several
views.
In carrying my invention into effect I may interweave the fusible conductor B
into and through an insulating and preferably refractory substance or material A,
such for instance as nsbestos, as shown by Figures 1, 14, 2, 24, 3, 3, 4 & 5, in
which case said fusible conductor B is alternatively stitched, woven, or passed
through the insulating substance A, and may be used in continuous lengths, and
cut off and bared for connection in such shorter lengths as may be desired.
Figures and 14 illustrate one method of interweaving, and Figures 2, 2, 3, 34,
4 and 5 interweaving at shorter intervals, and these may be extended upon the same
lines without departing from the essential features of my said invention. In
Figure 6 is shown a modification in which the fusible conductor B is threaded
through the substance of the insulating material A, and the ends connected to two
contact pieces D D', and a bridge or rigid conuector C maintains the whole at a
predetermined distance between the two terminals, which allows of the ready
interchanging or replacement of the fusible conductor when necessary. The
bridge or connector C may be of mica, porcelain, or any insulating substance
possessing sufficient rigidity, and the contact pieces D D are held in position
thereupon by the screws d d which may also serve to hold the fusible conductor B
in contact with D and D' or any equivalent fastening may be employed, such as
eyelets, or open rivets. Figure 7 shows a modification of the foregoing in which
the bridge is dispensed with and the insulating or refractory material A is of
such character as to maintain the distance between the contact pieces D D' which
in this case are shown slotted at ss for attachment to terminals. In any case in
which solid metallic contact pieces for the poles or terminals of the fusible
conductor, herein always referred to as D D', square, angular, slotted or pinned
beads may be formed thereon or attached thereto, to couform to the requirements
of the terminals to which the fuses are to be adapted. Figure 8 is a modification
of the arrangement shown by Figure 6, in which the fusible conductor B is in
multiple, and may be spread apart at the points where fusion or rupture is likely
to occur.
In any case I may prefer to use a multiple fusible conductor, whether the
strands are spread or arranged close together. Figure 9 shows a modification
in which the fusible conductor B has a free end, and is also provided with a solid
end D slotted or otherwise shaped, and one or more convolutions through an
insulating or refractory medium A. This is to provide for cut outs of various
sizes, and the ends may or may not be duplicated. Figure 10 is a plan view, and
Figure 10 sectional view, in which the fusible conductor B is threaded through
a china, porcelain, or other insulating and refractory base or foundation, having
two metallic ends D D suitably shaped to fit the terminals. Figure 11 is a plan
of a modification thereof in which the convolutions are doubled and the slots or
grooves are formed so as to ventilate the fuse when operative. Figure 12 is an
elevation of a modification in which two contact pieces D D' are attached to a
china or other base A, by screws d d', which may also serve to hold the ends of
the fusible conductor B in contact, the said conductor being threaded through A
in the manner before described. Figure 13 is an elevation of a modification of

page_text: the foregoing, in which the fusible conductor B is diagonally threaded through
the insulating base A, both vertically and transversely. These fuses with rigid
insulating and uninflammable bases, allow of a ready renewal or replacement of the
fusible conductor or conductors B and are practically indestructible and always
interchangeable within the range of the terminals to which they are adapted. The
conductors made according to Figures 1, 2, 3, 4 and 5 may be made in considerable
lengths, and cut off in short lengths as required for use, and such short lengths
may or may not be furnished with contact ends or contact pieces as herein before
described.
I do not confine myself to the use of any special fusible metal or the shape
thereof, which may be round, a twisted series of wires, or a strip or strips, or any
other conformation or shape, or to any special iusulating medium, the essential
features of iny invention being the interweaving or stitching of the aforesaid
fusible metal conductor or its equivalent into or through the said insulating
medium in an irregular direction, in single or multiple stran is, and made so as
to be readily adapted to various forms or types of cut outs or cut out terminals.
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 I
claim is:-
First. In fuses for electrical cut outs the method of and means for producing au
irregular path or direction of the fusible conductor in conjunction with an inter-
posed insulating and preferably refractory substance or material substantially as
and for the purposes herein set forth and shown by the drawings.
Second. In fuses for electrical cut outs, the method of and means for interposing
an insulating or refractory substance or inaterial between the convolutions of an
irregularly disposed fusible conduetor or conductors, by means of stitching,
stranding, plaiting, or twisting, substantially as herein described with reference to
Figures 1, 14, 2, 24, 3, 4, and 5 of the appended drawings.
Third. In fuses for electrical cut outs, the combination of an insulating bridge,
carrying a single or multiple fusible conductor interwoven or disposed through,
within or between an insulating or refractory medium, substantially as and for the
purposes herein described with reference to Figures 6, 7, 8, 9, 10, 11, 12, and 13 of
the appended sheet of drawings.
Fourth. In fuses for electrical cut outs, the employment of a mica, china,
porcelaiu, or other base, in combination with a fusible conductor or conductors
stranded or separated irregularly disposed through within or about it, with suitably
shaped contact pieces substantially as and for the purposes herein set forth with
reference to Figures 10, 11, 12, and 13 of the appended drawings.
Dated this 10th 1.com 1000
FREDK. WALKER,
73 St. Stephen's Road, Upton Park, E.,
Late of 88 Queen Victoria Street, E.C., Agent for the Applicant.