Improvements in Electric Cut-outs.
Year: 1890

page_text: Date of Application, 1st July, 1890-Accepted, 30th Aug., 1850
COMPLETE SPECIFICATION.
Improvements in Electric Cut-outs.
A communication from LORENZO B. FAVOR, of Gloucester, in the County of Essex
and Commonwealth of Massachusetts, United States of America.
1, ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
M.I.M.E., 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 :-
This invention relates to devices for the protection of low tension electrical circuits
and has for its object to obviate any danger or damage that might result from the
accidental charging of a telephone, telegraph or other low tension circuit with a high
tension current.
In the accompanying drawings this invention is represented in perspective by
Fig. 1; Fig. 2 is a side elevation referred to more fully hereinafter.
The base board, A, is composed of wood, or other non-conducting material and
serves as a base to support the various mechanisms mounted thereon, composing this
invention.
.
The post a, is connected with the line wire and by a suitable line connection with
the post, b. On the post, b, is mounted a lever B, one end of which is connected with a
spring e, that operates to bear upwardly the opposite end of said lever successively
against the fusible conducting wires, f, as further described hereinafter. Said fusible
wires, f, are mounted on posts, h, h, one of which posts is a non-conductor.
The wires are preferably arranged parallel with each other, substantially as
represented. The post, n, connects with the line, M, which leads to a telephone or
other instrument operated by a low tension current.
On a post, 1, is set the metallic cap, 5. Between the cap, 5, and post, n, connection
is established, electrically, by means of wire conductor, 6. On post 4, immediately
below cap, 5, is a hard rubber or other insulating piece, 7, which prevents communi-
cation, electrically, between the post and cap in any direct line. On post, 4, is
mounted a contact-plate, 8, which is composed of spring metal or is operated upon by
springs or other devices so as to bear normally with a yielding pressure against the
cap, 5, and also to permit being withdrawn from contact with cap, 5, when desired, or
occasion demands, as described hereinafter. On the post, 9, is mounted a conducting
plate, 10, which is composed of spring material or is otherwise set to be acted upon by
springs or weight devices so as to, normally, set above the plate, 8, with its forward
end projecting over the plate, 8, and also to permit downwardly yielding movement
so as to engage and draw the plate, 8, away from contact with cap, 5, when occasion
requires. The Fig. 2 of the accompanying drawings represents, in side elevation, the
normal position of said parts and their relation to each other. The downward.
movement of plate, 10, is effected by electric current acting through magnet, 12, as
hereinafter stated. The terminal, 10, is electrically connected with the ground, or
line of the circuit which leads from the instrument through a conductor consisting of
line, 13, post, 14, post, 9, line 15. From the line wire a low tension current passes
through this invention to a telephone or other instrument, located in a building or
other suitable place. To this end the normal low tension current passes to binding
post, a, thence along wire, 20, post, b, lever, B, to the member of fusible conductors, f,
with which the lever, B, contacts, temporarily and thence along such member through
post, h, line 21 and post, 4, to plate, 8, and thence through plate, 8, cap, 5, line, 6,
post, n, and line, M, to the telephone or other-instrument. During this time, the
netallic armature plate, 10, remains lifted to its normal position, as indicated in dotted
ines (Fig. 2) and thus permits the plate, 8, to contact, normally, with cap, 5, as
ereinbefore described.

page_text: Should an abnormal shock, such as lightning, strike the main wire, the current of
electricity caused thereby would pass through the instrument as far as the fusible
member, f, against which the lever, B, might for that time, be in contact. The said
member would promptly fuse and at once and immediately open the circuit. Lever, B,
is then acted upon by spring, e, and made to approach to contact with the next fusible
conductor, f. A stroke of lightning, being momentary and of no appreciable
duration, will cause but a single wire to fuse. In case, however, the line wire contacts
with an electric light wire or other conductor, carrying a high tension current,
continuously, the several members, f, will fuse, successively, thereby completely
opening the circuit and thus give warning to the central office that a high tension and
dangerous current is crossed with the low tension or normal current of a telephonic or
telegraphic instrument as the case may be.
It will thus be observed that accident or damage from a high tension electric
current is obviated by the fusible conductors, f, but owing to the difficulty of producing
fusible conductors that will fuse under the action of a current of less than about one
ampere, it becomes necessary to provide against damage from such electric currents as
are of sufficiently low tension to pass without fusing the conductor, f, but which are
of sufficient high tension to cause damage by setting fire or otherwise interfering with.
the low tension instrument or the building wherein it may be contained.
To this end it is that I have made use of the metallic coil, 12, and the armature
plate, 10. The plate, 10, is set normally above the conductor, 8, and so as to be drawn
downward by an electric current of sufficient strength acting on and magnetizing
the coil, 12. When drawn downwardly, the plate, 10, engages the plate, 8, and forces
it also downwardly, as shown in full lines Fig. 2 and thus disconnects the plate, 8,
electrically from cap, 5, and opens the circuit to the telephone or other instrument
and conducts the current over the conductor composed of post, 9, line, 13, post, 14,
line, 15, to its terminal connection, which may be the ground or the leading out line of
the circuit conductor; in either case the telephone or other instrument is temporarily
cut out of the circuit.
The plate, 10, is set so as to be drawn downwardly by the coil, 12, when acted upon
by an electric current varying in tension from such as will fuse the conductor, f, down
to a current of such low tension, say about twenty ohms, that can do no harm. The
normal current, acting upon the telephone or other instrument, is below this tension
and will not magnetize the coil, 12, sufficiently to act upon plate, 10.
From the foregoing it will be understood that all such intermediate currents are
conducted away from the instrument, after passing the fusible conductor and before
reaching the point of doing damage, i.e., the building or instrument to be protected.
It will be understood that the lever, B, instead of being moved to contact, successively,
with the fusible conductors, f, might be fixed and the conductors mounted on a
mechanism movable to bring the conductors, f, successively, into contact with the
lever. I would not, therefore, limit this invention to the particular construction and
arrangement of parts herein shown.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1st-An electric circuit conductor having one or more interposed sections of fusible,
conducting material and an electro-magnet in connection with the circuit conductor,
combined with a cut-out conductor and a movable terminal plate, said terminal
being normally out of contact with the electro-magnet and movable by an electric
charge, abnormal to the circuit conductor in the electro-magnet, to open the circuit
conductor, substantially as described.
2nd An electric circuit conductor having a movable section, as 8, and electro-
magnet in connection with the circuit conductor, combined with the cut-out conductor
and movable terminal, 10, said terminal being normally out of contact with the circuit
conductor and movable by an electric charge abnormal to the circuit conductor in the
electro magnet, to contact with and open the circuit conductor, substantially as described.

page_text: :-
3rd An electric circuit conductor having one or more interposed sections of
fusible, conducting material, an electro-magnet, in connection with the circuit
conductor combined with a cut-out conductor and movable terminal said cut-out
conductor being normally out of connection with the circuit conductor and said
terminal being actuatable by an electric charge over the circuit conductor, in the
electro-magnet, of a tension intermediate the tension of the current, normal to the
circuit conductor, and a current of tension high enough to melt the fusible section,
of said circuit conductor, to contact with and open the circuit conductor, substantially
as described.
4th In an electric circuit the movable plate, 8, the movable terminal, 10, and
the electro-magnet, 12, and electric connections, substantially as described.
5th-The combination of the circuit conductor, the interposed series of fusible
conductors, f, and lever, B, and connections, substantially as described.
6th-The combination of the circuit conductor, the interposed series of fusible
conductors, f, a movable contact lever and means whereby said lever is made to
automatically contact successively with the fusible conductors, substantially as
described.
DLL: 1-1
CT 1900
W. P. THOMPSON & BOULT,
Agents for the Applicant.