Improvements in and relating to Cut-out or Safety Devices for Electric Circuits.
Year: 1888

page_text: Date of Application, 28th Sept., 1888
Complete Specification Left, 12th Apr., 1889
Complete Specification Accepted, 8th June, 1889
PROVISIONAL SPECIFICATION.
Improvements in and relating to Cut-out or Safety Devices for
Electric Circuits.
We, JOHN KENDALL, of School Cottage, Clements Road, Notting Hill in the
County of Middlesex, Engineer, and OWEN COOPER, of 70 High Street Notting Hill,
in the County of Middlesex, Butcher, do hereby declare the nature of this invention
to be as follows:-
Our invention relates to electrical cut-out or safety devices of the kind or class
wherein a conductor or connecting piece composed of easily fusible metal or alloy
forms a part of the electric circuit, so that any abnormal increase in the intensity of
the current will cause the fusion of the said conductor or connecting piece, and over-
heating of the wires in other parts of the circuit will be prevented.
Our said invention comprises a method of providing for the automatic indication,
by the sounding of a bell or otherwise, of the fusion of the said conductor or con-
necting piece, so that it can be at once replaced by a new one, and the inconvenience
arising from the temporary cessation of the current will be minimized.
For this purpose we employ a movable holder for the fusible conductor or connecting
piece and means whereby, when the latter is fused, the said holder will actuate a
circuit-closing device and thus give an alarm by ringing a bell or otherwise.
Our said invention is conveniently and advantageously carried into practice as
hereinafter described, that is to say:-Two rods are fitted to slide in tubes or sockets so
that they are in the same straight line and are provided at their outer ends with
conical or cup-shaped cavities adapted to engage with the ends of the fusible
conductor. The said tubes or sockets are connected in any convenient manner to the
wires of the electric circuit and springs are arranged in the said tubes or sockets so
that they press the rods outward and thus retain them in engagement with the fusible
conductor. The said rods and springs are, moreover, so arranged that, when the said
conductor is fused, the said rods will be moved towards each other by their springs,
but cannot be brought into contact with each other. The rods can then be very
readily pushed back into their sockets and a new fusible conductor inserted between
them, without the necessity for using.any tools in effecting this operation.

page_text: The cup-shaped ends of the rods are preferably surrounded by insulating material
to obviate any liability of the current passing through a person while inserting a new
conductor.
In combination with one of the said rods is arranged a suitable circuit-closing
device, so that, when the aforesaid conductor is fused, the said rod will, in being
pushed outward by its spring, actuate the said device and close or complete an electric
circuit in which is included an electric bell.
We sometimes arrange a great number of our safety-devices side by side and
combine therewith a single electric bell and meáns whereby, when either of the
conductors is fused, the circuit of the said bell will be completed, for instance we use
for this purpose a pivoted lever having a series of teeth, like a comb, each of which
teeth is arranged to be actuated by one of the spring rods above described so as to
turn the said lever and thus close the circuit of the electric bell.
In some instances, we use a single spring rod in combination with a fixed rod having
a cup-shaped end for the purpose above specified.
Dated this 28th day of September 1888.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicants.

page_text: Improvements in and relating to Cut-out or Safety Devices for
Electric Circuits.
We JOHN KENDALL of School Cottage, Clements Road, Notting Hill, in the:
County of Middlesex, Engineer and OWEN COOPER of 70 High Street, Notting Hill
in the County of Middlesex Butcher, 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 :-
Our invention relates to electrical cut-out or safety-devices of the kind or class
wherein a conductor or connecting piece composed of easily fusible metal or alloy.
forms a part of the electric circuit so that any abnormal increase in the intensity of
the current will cause the fusion of the said conductor or connecting piece thus,
preventing overheating of the wires in other parts of the circuit
Our improved device or safety fuse comprises a movable holder for the fusible,
conductor or connecting piece and means whereby, when the said conductor or
connecting piece is fused or melted, the said holder will be caused to actuate a circuit
closing device and thus give an alarin by ringing a bell or otherwise.
By the employment of this device we provide for the automatic indication, by the
sounding of a bell or otherwise, of the fusion of the said conductor or connecting.
piece so that it can be at once replaced by a new one, and the inconvenience arising
from the temporary cessation of the current will be minimised.
In the accompanying drawing we have shown how our said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a plan, and”
Figure 2 a perspective view showing one form of our improved device.
Figure 3 is a vertical longitudinal central section, drawn to an enlarged scale,
showing details of construction.
Like letters indicate corresponding parts throughout the drawing.
A, A are two rods or plungers fitted to slide freely in tubes or sockets B so that
they are in line with each other. The tubes or sockets B are secured by means of
set screws B2 or in any other convenient manner, in brackets B' firmly attached to or
forming part of a base-plate B³, which may be secured to a .block B of wood or
other suitable material. C is the fusible conductor. The rods or plungers A are
preferably provided at their outer ends with conical or cup-shaped cavities A¹
(Figure 3) adapted to engage with the ends of the said fusible conductor C. Spiral
•

page_text: springs D are arranged in the said tubes or sockets B so that they tend to push the
rods or plungers A outward and thus retain them in engagement with the fusible
conductor C. The rods or plungers A are made hollow to allow the wires E of the
electric circuit to pass into or through them, the said wires also passing through
suitable holes in the tubes or sockets B and through the spiral springs D. The
wires E are retained in position either by the set-screws F or by the set screws F¹.
The rods or plungers A and springs D are so arranged that, when the conductor C
is fused, the said rods or plungers A will be moved towards each other by the
springs D, but cannot be brought into contact with each other by reason of the
stops A² which limit their movement. The rods or plungers A can then be very
readily pushed back into the tubes or sockets B and a new fusible conductor C
inserted between them, without the necessity for using any tools in effecting this
operation.
The conical or cup-shaped ends of the rods or plungers A are preferably surrounded
by insulating material to obviate any liability of the current passing through a person
while inserting a new conductor.
In combination with the said rods or plungers A we arrange a suitable circuit-
closing device so that when the conductor C is fused, the said rods or plungers will,
on being pushed outward by their springs D, actuate the said device. and close or
complete an electric circuit in which is included an electric bell. In the apparatus
shown in the drawing, the circuit-closing device consists of pins or studs A³ fixed in
the rods or plungers A, and arranged to come in contact with pins or studs A fixed
in the base-plate B3, when the rods or plungers A are moved towards each other as
ahove described, the pins, or studs A³ being connected with the wires of the electric
bell circuit. By those means when the conductor C is fused, the. electric bell will be
rung and. indication thus afforded that such is the case.
We sometimes arrange a great number of our safety devices side by side and
combine therewith a single electric beil and means whereby when either of the con-
ductors is fused, the circuit of the said bell will be completed. For instance we use
for this purpose a pivoted lever having a series of teeth like a comb, each of which
teeth is arranged to be actuated by one of the spring rods or plungers above described
(when the corresponding conductor is fused) so as to turn the said lever and thus
close the circuit of the electric bell.
The safety-devices and electric bell may advantageously be arranged in the engine-
room of an electric light installation. The engineer can in this case, ascertain at
once when a circuit is interrupted, by the fusing of a conductor, without having to
wait for a communication to this effect from the persons using the lights in this
circuit.
Our improved safety-device is also advantageous as a fire alarm, one or more of the
said devices being placed in those parts of a building in which a fire is likely to break
out and being so arranged that, when the connecting piece or conductor, is fused by
the heat of the fire, the circuit of an electric bell will be closed and the bell rung.
In this case we may use for our purpose electric bells employed for other purposes
upon the premises. Should a fire take place the fusible conductor will be fused or
melted in a few seconds and the springs forcing out the rods or plungers A will
close or complete the electric bell circuit as hereinbefore described thus indicating
the presence of the fire and its locality.
It is obvious that we can somewhat modify the construction of our device without
departing from the nature of our said invention. For instance, we can employ a
single spring plunger or rod in combination with a fixed rod or stem with or without
the conical or cup shaped cavity herein before described.
Having, now particularly described and ascertained. the nature of our, said inven-
tion and in what manner the same, is to be performed we; wish it. understood
that we claim :-
First The combination, with a fusible rod or conductor, of one or more spring

page_text: rods or plungers whereby,, when the said rod or conductor is fused, an electric circuit
will be closed or completed, for the purposes above specified.
Second. The improved cut-out or safety-device constructed substantially as
described with reference to the accompanying drawing, and for the purposes
specified.
Dated this 10th day of April 1889.
JOHN KENDALL.
OWEN COOPER.
Haseline, Lake & Co.,
45, Southampton Buildings, London,
Agents for the Applicants.
JOHN
KENDALL.
OWEN COOPER.
Haseltine, Lake & Co.,
45, Southampton Buildings, London,
Agents for the Applicants.