An Improved Cut-out Fuse.
Year: 1891

page_text: Date of Application, 7th Feb., 1891
Complete Specification Left, 7th Dec., 1891-Accepted, 9th Jan., 1892
PROVISIONAL SPECIFICATION.
An Improved Cut-out Fuse.
1, WILLIAM WILSON HORN of the firm of Horn and Son of 151 Strand in the
County of Middlesex Patent Agent do hereby declare the nature of this inven-
tion (à communication to me from George Herbert Whittingham of Baltimore
State of Maryland United States of America Inventor) to be as follows:-
This my invention relates to an improved cut-out fuse for incandescent lamps
and other purposes where it is desired to introduce a fuse into an electric circuit
and my object is to devise a cut-out which shall be of simple construction and in
which the fuse can be readily replaced when destroyed.
My improved cut-out consists of a block or bed of an insulating or non conducting
material, which has flexible brushes attached thereto in any convenient manner,.
said brushes being connected with the wires of an electric circuit. The said bed
has a central circular indentation in which the fuse holder turns.
The said fuse holder consists of a cup or block of insulating material of any
suitable shape, provided that its longitudinal diameter is greater than its transverse
diameter and having its longest diameter to correspond and register with the before
mentioned socket or indentation in the bed of the apparatus.
The said fuse holder has a slot along its longest diameter in which is placed a
ribbon of any suitable metal to form the fuse, the free ends of said ribbon being
bent over the ends of the fuse holder. A portion of the ends of the said holder
may be removed to form a socket or shoulder for the same.
The said fuse holder is secured to the bed by a suitable joint and is constructed
so that when the cut-out is in the electric circuit the ends of the fusible ribbon come
in contact with the before mentioned brushes. When the fuse is destroyed by an.
excessive current the fuse holder may be readily removed from the bed by turning
it by means of a handle provided for the purpose a quarter revolution and the
flusible ribbon may be replaced without disturbing the remainder of the apparatus.
The details of construction of my improved cut-out may be slightly varied without
departing from the spirit of my invention.
Dated this 7th day of February 1891
HORN & SON,
Applicant's Agents.
COMPLETE SPECIFICATION.
An Improved Cut-out Fuse.
I, WILLIAM WILSON HORN of the firm of Horn & Son, of 151 Strand, London
in the County of Middlesex, Patent Agents, do hereby declare the nature of this
invention (a communication to me from abroad, from George Herbert Whittingham
of Baltimore State of Maryland United States of America, Inventor) 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 fuse cut outs for incandescent lamps and other purposes,
where it is desired to introduce a fuse into an electrical circuit. In wiring for
electrical lighting for incandescent lamps, it is necessary to protect the lamp from
being destroyed by a current of great intensity, by introducing into the circuit a
fuse which will be melted by said current and the circuit destroyed. Many such
devices have been designed, but the object of the invention which is the subject of
this application, is to cheapen construction by simplifying the structure, as well as
Pine T

page_text: to make a cut-out device which can be quickly replaced when the fuse has been
burnt, by any one, without the exercise of skill in electric wiring and without the
use of any instrument, not even a screw-driver.
In the drawings,
Figure 1, represents a plan of my fuse, showing two fuse devices in the two
positions of the apparatus, one with the fuse in the circuit, and the other with the
fuse-holder at right angles to its former position.
Figure 2, is a view of the bottom side of the fuse holder, showing the fuse in
position.
Figure 3, is a view of the top side of the same showing the fuse in position.
Figure 4, is an end elevation of the same showing fuse in position.
Figure 5, is a side elevation of the same, showing fuse in position.
Figure 6, is a side elevation of the device with one of the contact brushes and
the bed in section through the line x-x, Figure 1.
Figure 7, is a plan of a modified form of fuse structure embodying the same
general principle as form shown in Figure 1.
Figures 8 and 9, are plans of the fuse holder and cut out device slightly modified
in form.
Referring to Figures 1 and 6, 1 is a bed made preferably of porcelain, in the
centre of which is a circular indentation or socket 2, of slight depth, in which the
fuse holder rests and revolves. The fuse holder 3, is a cup of porcelain or other
refractory material, provided with handle 4, on the bottom; the cup is shaped in
the form of two circles which intersect one another, so as to cause the ends of the
cup to be convex, and the sides concave where the circles intersect one another.
The long diameter of the cup is the same as the diameter of the socket 2, so when
the cup rests in said socket, it will revolve therein and fit snugly; the sides of the
cup are provided with the concave indentations for the purpose of making points
which will never be touched by the contact brushes, thereby avoiding the possibility
of coating the exterior of the cup with metal rubbed from the brushes and thereby
forming a conductor from one brush to the other around the fuse. The edges of
the cup are provided with a slot 5, which is in the line of the greater diameter of
the cup, and which extends about two-thirds of the depth of the sides of the cup.
Upon the exterior of the cup at its ends and on opposite sides of the slot 5, the
surface of the cup is cut away at right angles with the slot 5, from the bottom of
the cup toward its rim, leaving however, a thin edge of the rim which is of the full
contour of the cup, forming the notches 6, 6, on opposite ends of the cup, and on
opposite sides of the slot 5. This structure is shown plainly in Figures 4 and 6.
7, is a section of fuse ribbon which is placed in the slot 5, across the cup; and the
projecting ends are bent in opposite direction into the notches 6. 6. by which it is
held in place. 8, 8, are contact brushes secured to binding posts 9, 9, to which the
circuit wires are connected, the contact brushes 8, 8, extend from the binding posts
toward one another, their extremities standing over the socket 2, at such a distance
apart, that the cup 3, may be inserted between them when turned in the position
shown on the right of Figure 1, in which the shorter diameter of the cup is between
the brushes, and they do not touch it on either side. The brushes are made of
metal having some elasticity, so that when the cup is turned between them by the
handle 4, they will be pressed apart by the ends of the cup, and will exert a
pressure upon said ends. When the cup is turned so as to place the longer diameter
of the cup between the extremities of the brushes, they will fall into the notches 6, 6,
and upon the ends of the fuse 7, which lie in said notches, thereby establishing a
circuit between said brushes or contact strips, through the fuse 7. If now the fuse
is burned by an excessive current, the circuit will be broken. A quarter turn of
the cup from the position shown on the left of Figure 1, to the position shown on
the right of Figure 1, will release the cup from the hold of the brushes and it may
be taken from its socket and a fresh piece of fuse inserted into the slot 5, the ends
being bent as before described in opposite directions into the notches 6 6. The cup
is then replaced into the socket 2, in the position shown on the right of Figure 1,

page_text: and given a quarter turn by its handle, into the position shown on the left of
Figure 1, in which position as before stated, the brushes 88 will be in contact with
the turned over ends of fuse 7, but the circuit will be re-established without injury
to the socket or without taking the apparatus apart otherwise than to remove
the cup.
The brushes 8, 8, rest upon the bed 1, and stand over the socket 2, the rim
of the cup below the notches 6, 6, is of such a width that when the cup is inserted
in the socket, the upper side of said rim will be on the level of the surface of the
bed I, thus when the cup is turned from the position shown on the right of
Figure 1, to the position shown on the left of Figure 1, and the brushes fall into
the notches 6, 6, the ends of said brushes will stand upon the rim and hold the cup
firmly in the socket. The bed and cup being made of porcelain, it is unnecessary
to provide the device with any supplemental cover, because the fuse is enclosed
within the cup and is surrounded on all sides by porcelain, or other similar material
may be used if preferred.
Figure 7 illustrates a modified form of construction, which consists of a cup 10,
slotted as before, on its longer diameter and provided at its rim with projecting
lips 11, 11, the fuse 12, as before, is placed in the slot 13, and bent under the lips
in either direction. 14, 14, are the contact strips connected to the binding
posts, 15, 15, which are in the circuit. These contact strips project from the
binding posts in the same direction, parallel to one another. Between these strips
the cup 10, is placed so as to push them slightly apart and make a contact between
their extremities and the bent over ends of the fuse. The lugs, 11, 11, being below
the strips and being between them and the bed 16. Figures 8 and 9, are slightly
different forms of the same structure, differing only from the form shown in
Figure 7, in that the cup is provided on either end with notches which are engaged
with the contact strips, and the cup is held in place by them the lower side of the
notch being the projecting rim of the cup, and being between the brushes and
the bed.
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:
1. In a thermal cut out, the combination of a cup of refractory material, the edge
of which is slotted with a base of similar material, having a socket, circular in form
and of the same diameter as the cup, into which the cup when inverted fits and
may revolve, a section of fuse ribbon inserted in the slot of the cup, the projecting
ends thereof being bent over in contact with the exterior of the cup, and strips or
brushes connected to the terminals of an electric circuit, which when the cup is
pressed between them will make contact with the turned over ends of the fuse and
complete the circuit through said fuse, substantially as described.
2. In a thermal cut out, the combination of a cup of refractory material, of
greater diameter in length than width, and having indentations in the sides thereof,
and the edge of the cup slotted in the line of its longer diameter, with a base of
similar material having a circular socket of the same diameter as the longer diameter
of the cup, in which the cup when inverted, fits and may revolve, a section of fuse
ribbon inserted in said slot in the cup rim and having its projecting ends turned
over in contact with the exterior of the cup, and contact strips or brushes, con-
nected to the terminals of an electric circuit, which when the longer diameter of
the cup is pressed between them, will make contact with the turned over ends of
the fuse and complete the circuit through said fuse.
3. In a thermal cut out, the combination of a cup of refractory material of
greater diameter in length than width, and having its rim slotted in the line of its
greater diameter with a fuse ribbon inserted in said slot the projecting ends
thereof being bent over in contact with the exterior of the cup, and contact strips
connected to the terminals of an electric circuit, so located that the distance
between their extremities will be less than the greater diameter of the cup, but

page_text: greater than the shorter diameter, so that when the cup is revolved between them,
they will come into contact with the ends of the cup and the extremities of the
fuse which projects therefrom, but will not touch the sides, when they are turned
toward said contact strips, substantially as described.
4. In a thermal cut out, the combination of a cup of refractory material of
greater diameter in length than width, and having its rim slotted in the line of its
greater diameter and provided on the exterior at its ends and on opposite sides of
the slot, with notches which are below the rim, with a fuse ribbon inserted in said
slot and having its projecting ends turned over in opposite directions into the
notches, and contact strips connected to the terminals of an electric circuit, so
located that the distance between their extremities will be less than the greater
diameter of the cup, but greater than the shorter diameter, so that when the cup
revolved between them, they will come into contact with the ends of the cup and
fall into the notches therein, and upon the extremities of the fuse which lie in said
notches, but will not touch the sides, when they are turned toward said contact
strips, substantially as described.
Dated this 7th day of December 1891. .
is
HORN & SON,
Applicant's Agents.