Improved Automatic Electric Cut-out.
Year: 1889

page_text: Date of Application, 2nd July, 1889-Accepted, 3rd Aug., 1889
COMPLETE DI BOITICATION.
Improved Automatic Electric Cut-out.
I, STANLEY CHARLES CUTHBERT CURRIE, a subject of the Queen of Great Britain,
but now residing at 813 Drexel Building Philadelphia, in the County of Philadelphia,
and State of Pennsylvania, Electrical Engineer, do hereby declare the nature of my
invention for an IMPROVED AUTOMATIC ELECTRIC CUT-OUT, and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statements :-
The principal object of my invention is to provide a simple, durable and sensitive
automatic electric cut-out for various uses and purposes, possessing the following
characteristic features and desirable qualities; first, a device of good conducting
material to afford a continuous path for the passage of a current of electricity;
second, a device constructed and arranged so that when the electric current becomes
more intense than the device is adjusted to carry, causing the circuit through the
same to be automatically broken; and third, to provide a device that can be readily
readjusted as soon as any defect in the circuit has been rectified.
My invention consists of two wires or pieces of metal or other good conducting
material interposed in an electric circuit and suitably supported at one of their ends by a
connecting device and with portions of the wires or pieces imbedded in an insulating
substance or material of poor electrical conductivity, but susceptible of being melted
at a low temperature with portions of said wires or pieces immersed in a conducting
fluid contained in a bulb, tube or other suitable vessel.
My invention further consists of two inversely disposed wires or pieces of metal or
material of good conductivity supported at one of their ends by a connecting device
composed of insulating material and portions thereof attached to or otherwise held by
an insulated yoke and said wires or pieces imbedded in a substance or material of
high resistance, but capable of being readily melted and with portions thereof
immersed in a conducting fluid contained in a vessel, bulb or other container, with a
loop or band of insulating material circumscribing the vessel or bulb to permit the
same to fall sufficiently when the circuit is automatically broken through the device by
the melting of the substance or material of poor electrical conductivity that said
wires are imbedded in and supported in the vessel.
The nature and characteristic features of my invention will be more fully
understood taken in connection with the accompanying drawings forming part hereof;
and in which
Figure 1, is a vertical central section of the automatic cut-out device embodying
the principal characteristic features of my invention; and
Fig. 2, is a plan view thereof, showing the wires which lead to or from a source of
electricity.
Referring to the drawings for a further description of my invention, A is a block
of wood, ebonite or other preferred insulating material which constitutes the frame of
the device. The inversely disposed wires or pieces B and B', are supported in or by
said frame which is provided with binding screws C and C¹. The lower extremities
of said wires are immersed in a fluid composed of mercury or other preferred liquid D,
of high electrical conductivity contained in a bulb, tube or other vessel E, made of
glass or other preferred insulating material. Portions of the wires B and B', are
iimbedded in the tube, bulb or other vessel E, in paraffine wax or other preferred poor
conducting material, but such as is susceptible of being melted at a lower temperature
than will melt the wires or pieces of metal of good conducting material B and B'.
The yoke G, composed of ebonite or other preferred insulating material consists of
a stretcher 9, which is provided with side grooves h and h¹. The wires B and B¹,
engaging in the grooves and, of the yoke G, are held to place by means of a band

page_text: of insulating material H. A band of rubber or other preferred material I, is caused
to circumscribe the tube, bulb or other containing vessel E. The action of the above
described cut-out device depends upon the heating of the wires by the passage of an
electric current larger than they are intended to carry to a temperature capable of
melting the insulating material in which they are imbedded or retained in position,
thereby effecting a change in the arrangement of the parts of the cut-out device to
cause the circuit to be broken.
The mode of operation of my improved cut-out device may be explained as
follows: The wire constituting the circuit from a source of electricity is cut and
the cut-out device interposed in the circuit by attaching the ends of the wires or
pieces to the respective binding screws C and C³, of the connecting-device A, to the
terminals of which are attached wires B and B. The electric current passes through
the binding screw C, and the wire B, to the liquid D contained in the tube or bulb E,
and thence through said liquid D, the wire B, and the binding screw C₁, to the wire
forming the circuit. In the event of the current passing through the circuit being
more intense than the cnt-out device is capable of withstanding the wires B and B¹,
will become heated and the paraffine wax or other material F, is melted in the bulb
or tube sufficiently to cause the bulb and the mercury contained therein to fall by
their own weight, thereby breaking the circuit. The bulb or tube E, is prevented
from falling farther than is necessary to always ensure the wires B and B', being with-
drawn from the conducting liquid, by the band I, surrounding the same.
It will be readily understood in the operation of my improved device that when the wire
or piece of metal becomes heated up by the electric current sufficiently to cause the
paraffine wax or other similar material to melt, the tube will fall, whereby the contact
of the wires with the mercury or other suitable material or substance will be destroyed
and consequently the electric circuit broken, but, however, in the fall of the tube the
same is checked by the insulated loop or band I, coming in contact with the yoke G.
The quantity of current in the circuit necessary to heat the wire or piece B or B¹,
sufficiently to melt the wax and destroy contact and consequently to cause the tube to
fall and the circuit to be broken, may be predetermined by either increasing or
diminishing the relative size of the wires or pieces B and B¹, and the size of the wire
forining the circuit. It may be remarked that the paraffine wax or other preferred
insulating material susceptible of being melted at a lower temperature than would
melt the wires, not only performs the functions hereinabove described, but also protects
the conducting liquid from being exposed to the atmosphere.
The instrument may be adjusted either by pressing the tube upward so that the
wires B and B', pierce or pass through the paraffine wax or other preferred insulating
material or substance susceptible of being melted at a low temperature and with the
wires again immersed in the mercury or other preferred conducting liquid, or the
paraffine wax or other preferred insulating material may be melted and the wires
readjusted as in the first instance.
Having now particularly described and ascertained the nature and objects of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. An electric cut-out device consisting of two pieces of metal interposed in a circuit
and engaging with and held by an insulated yoke and said wires embedded in an
insulating substance susceptible of being melted and immersed in a conducting
material in a vessel and a band circumscribing said vessel, substantially as and for the
purposes set forth.
2. An electric cut-out device, consisting of two wires or pieces of metal interposed
in an electric circuit and supported in or by a block composed of an insulating
material and said wires or pieces of metal in engagement with an insulated yoke and
imbedded in an insulating substance capable of being fused at a low temperature and
immersed in a conducting fluid in a vessel surrounded by a band, substantially as
and for the purposes set forth.
3. A cut-out device consisting of two pieces of metal interposed in an electric

page_text: circuit and imbedded in an insulating substance as paraffine wax and immersed in a
conducting fluid as mercury, substantially as and for the purposes described.
4. A cut-out device consisting of two pieces of metal interposed in an electric
circuit in engagement with a yoke and said pieces of metal imbedded in an insulating
substance capable of being melted at a lower temperature than will melt said pieces
of metal and portions thereof immersed in a conducting fluid in a vessel and means to
prevent said vessel from falling and to allow of the device being re-adjusted after the
circuit is broken, substantially as described.
5. The combination with two pieces of metal interposed in a circuit and a support-
ing insulated yoke, of an insulating substance and a fluid contained within a vessel
and a supporting yoke, substantially as and for the purposes set forth.
In witness whereof, I have hereunto set my signature in the presence of two
subscribing witnesses at the City of Philadelphia, Pa., this 22nd day
1000
STANLEY CHARLES CUTHBERT CURRIE.
Witnesses:
AUGUSTUS BURBANK STOUGHTON.
HERMANN BORMANN.