Improvements in Devices for Automatically Interrupting an Electric Circuit under Predetermined Conditions.
Year: 1889

page_text: Date of Application, 28th May, 1889
Complete Specification Left, 28th Feb., 1890-Accepted, 29th Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Devices for Automatically Interrupting an Electric
Circuit under Predetermined Conditions.
A communication from abroad by THE WESTINGHOUSE ELECTRIC COMPANY, of
Pittsburgh, Pennsylvania, United States of America (Case 32).
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E. of the Agency for Foreign
Patent Solicitors, 6 Lord Street Liverpool and 6 Bank Street Manchester both in
the County of Lancaster and 323 High Holborn in the County of Middlesex, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
The invention relates to the construction of a device for automatically interrupting
an electric circuit under predetermined conditions. The special object of the invention
is to provide means for interrupting the connections of a circuit supplied by alternating
electric currents and employed in the process of treating carbon filaments.
It has been found that carbon filaments may be treated with advantage by alternating
electric currents, and it is desirable that after the treatment has proceeded to a
certain point, the circuit should be automatically interrupted so that all the filaments
after treatment shall have the same resistance. This invention is designed to provide
a circuit-controlling device which shall insure that the circuit leading to the filaments
shall be interrupted, and the treatment thereof terminate when the resistance of the
filament has decreased to a certain predetermined point.
The invention will be described in connection with the accompanying drawings in
which Figure 1 is a front elevation and Figure 2 is a detail. Figure 3 is a top view
of a portion. The circuit-connections are shown in diagram.
Referring to the Figures
A represents a suitable base upon which various parts of the apparatus are supported.
Upon a pillar B there is carried a centrally pivoted lever b. From the respective ends
of this lever there are supported cores f and f¹ which respectively enter stationary
solenoids g and g¹. The cores are preferably composed of insulated laminae of soft
iron or soft iron wires.
In the
The cores are movable freely within the coils.
diagram there is shown at A' any suitable source of alternating electric currents.
The primary coil p of an electric converter P is connected in the circuit of the
source A¹. The secondary coil s is provided with two circuits. One of these consists
of a conductor leading through a suitable adjustable artificial resistance m to a
binding post h. This post is connected by a conductor 2, through the solenoid
the conductor 3 leads from this solenoid to a binding post i which is connected, by a
conductor 4, with the other terminal of the secondary coil s.
and
The second circuit consists of a conductor 5 leading from the conductor 1 to the
filament represented at n which is to be treated, in any well known manner, as for
instance by being heated in an atmosphere of hydro-carbon. A conductor 6 leads from
this filament to the binding post k, and a conductor 7 leads from this post to the
solenoid g¹. A conductor 8 leads from this solenoid to an insulated contact-point c.
When the parts are in position shown in Figure 1, a contact spring c¹ is pressed
against the point c. This spring c is in electric connection through the frame or
support, or in any other convenient manner, with a conductor 9 leading to the
binding post i. Thus it will be seen that the solenoids g and g₁ are in branch
circuits, and that the circuit through the latter is completed only when the spring cl
is against the point c and the filament n is included between the conductors 5 and 6.
The spring c is carried upon a movable arm or lever a which is provided with a
hook or catch a'. This arm is pressed against the end of the lever 6 carrying the
core f¹, by a spring d. When the filament is inserted and ready to be treated, the

page_text: end of the lever b carrying the core f¹ is lifted, the arm a being pressed back against
the spring d. The end of the catch or projection a¹ then rests against the smooth end
of the lever b. This holds the spring c¹ against the point c. Now, as the treatment
proceeds, the resistance of the carbon becomes less by reason of the deposit from
the surrounding atmosphere of hydrocarbon, and therefore more current passes
through the solenoid g until the pull upon the core f¹ exceeds that upon the core
f
sufficiently to draw the end of the lever b' downward across the point of the catch, thus
allowing the arm a to be forced backward, separating the spring c¹ from the point c
and thus interrupting the circuit through the filament. As the current employed is an
alternating current, no injury is done to the contact points by the interruption of
the circuit, and moreover there still remains a closed secondary circuit through the
coil g. It will be noticed, however, that the catch a¹ prevents the lever 6 from
immediately tilting in the opposite direction under the influence of the solenoid g
acting upon the core f.
For the purpose of readily adjusting the device, a movable weight e may be applied
to a rod el carried upon the movable lever. The adjustable resistance m may be
employed, moreover, for determining the exact amount of resistance which shall be in
the filament n when the treatment is thus caused to cease.
Dated this 7th day of May 19080
WM. P. THOMPSON & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Devices for Automatically Interrupting an Electric
Circuit under Predetermined Conditions.
A communication from abroad by THE WESTINGHOUSE ELECTRIC COMPANY, of
Pittsburgh, Pennsylvania, United States of America (Case 32).
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in
the County of Lancaster and 323, High Holborn, in the County of Middlesex, Civil
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 :-
The invention relates to the construction of a device for automatically interrupting
an electric circuit under predetermined conditions.
The special object of the invention is to provide means for interrupting the con-
nections of a circuit supplied by alternating electric currents and employed in the
process of treating carbon filaments.
It has been found that carbon filaments may be treated with advantage by alternating
electric currents, and it is desirable that after the treatment has proceeded to a certain
point the circuit should be automatically interrupted, so that all the filaments after
treatment shall have the same resistance.
This invention is designed to provide a circuit controlling device which shall insure
that the circuit leading to the filaments shall be interrupted and the treatment thereof
terminate when the resistance of the filament has decreased to a certain predetermined
point.
The invention will be described in connection with the accompanying drawings, in
which :-
Figure 1 is a front elevation, and
Figure 2 is a detail.
Figure 3 is a top view of a portion of the invention.
Figure 4 shows a number of these arrangements worked from one dynamo, each
one of them, in this instance, being arranged slightly differently so as to show some
of the variations which can be used.
The circuit connections are shown in diagram.

page_text: Referring to the Figures 1, 2 and 3 :-
A represents a suitable base, upon which various parts of the apparatus are
supported. Upon a pillar B there is carried a centrally pivoted lever b. From the
respective ends of this lever there are supported cores and f, which respectively
enter stationary solenoids g and g¹. The cores are preferably composed of insulated
laminae of soft iron or soft iron wires. The cores are movable freely within the coils.
In the diagram there is shown at A¹ any suitable source of alternating electric
currents. The primary coil p of an electric converter P is connected in the circuit
of the source A¹. The secondary coils is provided with two circuits. One of these
consists of a conductor 1 leading through a suitable adjustable artificial resistance m
to a binding post h. This post is connected by a conductor 2 through the solenoid g,
and the conductor 3 leads from this solenoid to a binding post which is connected
by a conductor 4 with the other terminal of the secondary coils.
The second circuit consists of a conductor 5 leading from the conductor 1 to the
filament represented at n, which is to be treated in any well known manner-as, for
instance, by being heated in an atmosphere of hydro-carbon. A conductor 6 leads
from this filament to the binding post k, and a conductor 7 leads from this post to the
solenoid g¹. A conductor 8 leads from this solenoid to an insulated contact point c.
When the parts are in the position shown in Figure 1 a contact spring c¹ is pressed
against the point c. This spring c¹ is in electric connection through the frame or
support, or in any other convenient manner, with a conductor 9 leading to the binding
post . Thus it will be seen that the solenoids g and g₁ are in branch circuits, and
that the circuit through the latter is completed only when the spring c¹ is against the
point c, and the filament n is included between the conductors 5 and 6.
The spring c¹ is carried upon a movable arm or lever a, which is provided with a
hook or catch a'. This arm is pressed against the end of the lever b carrying the
core f¹ by a spring d. When the filament is inserted and ready to be treated, the end
of the lever b carrying the core f¹ is lifted, the arm a being pressed back against the
spring d. The end of the catch or projection a' then rests against the smooth end of
the lever b. This holds the spring against the point c. Now, as the treatment
proceeds, the resistance of the carbon becomes less by reason of the deposit from the
surrounding atmosphere of hydrocarbon, and therefore more current passes through
the solenoid g until the pull upon the core f¹ exceeds that upon the core f sufficiently
to draw the end of the lever 6 downward across the point of the catch, thus allowing
the arm a to be forced backward, separating the spring c¹ from the point c, and thus
interrupting the circuit through the filament. As the current employed is an
alternating current, no injury is done to the contact points by the interruption of the
circuit, and, moreover, there still remains a closed secondary circuit through the coil g.
It will be noticed, however, that the catch a prevents the lever b from immediately
tilting in the opposite direction under the influence of the solenoid g acting upon the
core f.
For the purpose of readily adjusting the device, a movable weight e may be applied
to a rod carried upon the movable lever. The adjustable resistance m may be
employed, moreover, for determining the exact amount of resistance which shall be in
the filament n when the treatment is thus caused to cease.
Referring now to Figure 4, this illustrates the apparatus connected with the dynamo
as in actual practice in which several filaments can be treated simultaneously. Like
letters refer to like parts on this drawing as in Figures 1, 2 and 3. Three filaments
with the apparatus necessary for treating them are shown. In the first-the one on
left hand it is arranged precisely as set forth in Figures 1, 2 and 3. In this it is
found that as the filament under treatment becomes nearer its standard resistance the
treatment goes on too quickly through its resistance falling. To remedy this the
impédance coil H is inserted as in the second (middle) arrangement. This impédance
coil can be of any ordinary construction, but as various sized lamps, having various
degrees of resistance, are often to be treated on the same apparatus, it is preferable to
have three or four different terminals I 12 13 1 in order to give various resistances as

page_text: required. This is shewn so that it can be thrown into circuit of nitt of the con-
verters P by means of the switches K'. By this means the treatment is rendered
slower that it would otherwise be towards the end of the operation, and hence the
deposition of carbon is more uniform through the entire treatment. The third
apparatus in the line commencing from the left hand side shows the two solenoids
both arranged on the same core, but working in opposition to each other, the same
result can be obtained by winding the wires together on one solenoid. A balance
weight J balances the core, in other respects the apparatus is identical, and these
three slight variations are merely shown as giving a few useful ways in which the
apparatus can be varied without departing from the principle of the invention.
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 correspondents, I declare that what I claim is :-
1. In an apparatus for treating filaments by means of the alternating current, the
combination of two solenoids acting upon one or more cores in opposition to each
other, a carbonised filament in circuit with one solenoid, and an automatic circuit
interrupter in series with only the last named solenoid and the filament, the whole
arranged in such manner that the circuit through the carbon filament shall be broken
the moment it arrives at the predetermined resistance.
2. The process of treating filaments which consists in dividing an alternating
current into two parts each passing through a separate solenoid, one passir; also
through the filament to be treated and a circuit interrupter and the two rolenoids
acting in opposition to each other on the same core or on two cores mechanically
united and so arranged that when the two branches reach a certain ratio the one to
the other the circuit containing the filament shall be automatically interrupted.
3. The improved apparatus for treating filaments by the alternating current whereby
the filaments are treated with great uniformity substantially as described and as
illustrated in the accompanying drawings.
Dated this 27th day of February 1890.
WM. P. THOMPSON & Co.,
Agents for the Applicant.