Improvements in Electromagnetic Circuit Breakers.
Year: 1897

page_text: Date of Application, 2nd Nov., 1897-Accepted, 18th Dec.,
1897
[Communicated from abroad by DANIEL C. SPRUANCE and MONTGOMERY, WADDELL,
of the Times Building, New York, in the State of New York, United States of
America.]
Improvements in Electromagnetic Circuit Breakers.
1. WILLIAM GEORGE HEYS of 70 Market Street, Manchester in the county of
Lancaster. Chartered Patent Agent. 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 electro-magnetic circuit-breakers, the primary object
being to provide an apparatus that will positively open an electric circuit under
certain prearranged conditions, in such a manner that there can be no possibility of
the circuit being completed or left in such a condition as will cause an arc to be
formed, by the accidental return to position, of the section of the circuit wherein
the opening is made. A further object is to provide a sensitive instrument: one
easily and accurately adjustable to operate under various current amperages and one
which may be readily reset after having operated.
The invention consists first in the method of opening a circuit by mechanically
breaking out a section thereof from between two terminals: second, in certain latch
and trigger mechanisms and third, in the details of construction.
The invention is illustrated in the accompanying drawings, in which Figure 1
is a front elevation of the improved circuit breaker and Figure 2 is a side elevation
of the same.
Referring to the drawing by letter, A represents a base of insulating material such
as slate or marble, upon which the parts of the circuit breaker are mounted: a and a¹
are two binding posts to which the wires of the circuit are connected and between
which the instrument is interposed. Upon the face of the base and along its central
vertical line, are permanently mounted, two terminal clips b and b¹ respectively,
provided with rectangular openings near their outer ends adapted to receive a
metallic bar & forming a part of the circuit. The clip nearest the binding post a¹ is
conductively connected therewith by a lug b². Above the upper clip is placed an
electro magnet consisting of a core e and a coil e¹. The core is in the form of a ring
or other closed figure having a segment removed to determine the location of its poles
and the operating position of the armature: this opening is made in the upper outer
side of the ring. The core consists of a series of thin plates of soft iron confined
between two end plates e² e² which latter have extending brackets e3 by which the core
is secured to the base A. The coil consists of several turns of bare wire coiled
about the core in such a manner as not to touch each other nor the core. One
terminal of the coil connects with the clip b', while the other terminal leads through
a suitable opening and a groove in the base A to the binding post a.
The arinature of the magnet is represented by f. It is supported at the extremities
of two arms f¹ pivoted at their opposite ends upon a shaft g. The armature normally
stands within the enclosure of the core and the arms straddle the core.
The

page_text: armature is supported in its normal or retracted position by an arm hattached at one
end to the shaft g and engaging with a ratchet i at its other end. This arm has a
kink or bend h' in it, by compressing the sides of which, the arm may be slightly
shortened to change its point of engagement with the ratchet and thus alter the
distance of the armature from the poles. A brass frane I consisting of two plates
secured to the opposite sides of the core of the magnet is used to support the shaft g,
the ratchet and another shaft j. The ratchet is formed directly in an extension ¹
from this frame, the extension flanking both sides of the core and the teeth being
cut in each at corresponding points. A scale, as will be seen, is marked upon the
ratchet for the purpose of indicating where the arın h should be set to determine
when the circuit breaker shall perform its function of opening the circuit. The
figures of the scale will indicate a graduation of amperes of current at any point
between the limits of which, the armature may be set to alter the attractive distance
between magnet and armature.
o indicates a latch lever in the form of a yoke; its two arms embrace the magnet
core and are pivoted at their extremities upon the ends of the shaft j. The cross
connection of the yoke stands in behind the magnet core, near the base A and
carries a tail piece of projecting downwards from its middle point and having a
slightly curved or hooked end o². The outer extremities of the yoke have excentric
hooks o³ formed thereupon and these, for the sake of strength and rigidity, are
connected together by a cross-bar o. p is a lever performing the functions of a
trigger. It is pivoted upon the shaft and has an outwardly reaching arm
terminating in a finger piece p', and an inwardly reaching arm provided with
a shoulder p² and a hook p³, the latter being located in the same vertical plane as
the tail piece o¹ on the yoke or latch lever. The outwardly reaching arm is provided
with a lug p extending into the space between the pole piece of the magnet core.
r is a yoke of heavy stiff wire, which we will call the hammer; its terininals are
coiled up into two heavy springs 1, 2, the ends of which are firmly secured into the
base A. These two springs are placed in line with each other upon the opposite sides
of the magnet core near the base and are held in place by a transverse rod ² extending
through the side plates supporting the core of the magnet and lying against the
inner surface of the springs on each side. The tendency of the spring is to force
the hammer towards the face of the base A and in this position, the hammer rests
upon two rubber cushions t t. The radial length of the hammer is such that it will
swing midway between the two clips b 6' and will engage with the hooks os on the
latch lever.
8
The metallic bar & hereinbefore referred to forms a section of the circuit interposed
between the clips band 6¹. This bar is adapted to be broken by the hammer in such
a way as to absolutely remove a section of it from between the two fixed clips, and
to this end it is formed with a number of transverse weakening grooves &¹ to
determine where it shall be broken. We prefer to have three of these grooves and
to arrange one of them near the middle point of the bar and the other two
respectively adjacent to the clips, so that the blow delivered by the hammer near the
middle point of the bar will fracture it at three points and remove a section of the
circuit in two pieces. This precludes the possibility of the removed section from
rebounding or otherwise accidently bridging the two clips and so closing or partially
closing the circuit, immediately after it has been opened. This obviously would be
accomplished if the bar were broken into any number of pieces above two, and
consequently the invention comprehends not only the removal of a section of the
circuit from between two fixed terminals, but also the breaking up of the removed
section into a plurality of pieces.
The operation of the circuit breaker is as follows: The normal position of the
parts is shewn in Figure. 2 where it will be seen that the hammer has been elevated
and is held against the tension of its springs by the hooks o³, the latch yoke o being
locked by contact with the shoulder p2 on the trigger. When the current in the
circuit rises to a predetermined maximum, the strength of the magnet becomes
sufficient to lift the armature into the gap between the two poles of the magnet core

page_text: and cause it to strike a blow against the lug pt on the trigger and swing the inner
enl of the trigger outward, thus releasing the yoke and allowing the hooks o³ to tilt
downward sufficiently to free the hammer. The springs controlling the hammer
cause it to make a quick powerful stroke across the middle of the bar s and shatter
it along the weakened lines, thus mechanically removing a section of the circuit
bodily from between the two terminals b, b¹. After fracturing the bar, the hammer
comes into rest upon the cushions t t. The tilting of the yoke o to release the
haniner causes the inner end of the yoke to rise until the hooked extremity of the
tail piece of passes above the hook p³ on the trigger, which latter then passes under
the end of the tail-piece and holds the inner end of the latch yoke in its elevated
position. This is convenient in re-setting the instrument, for, in this position, the
excentric hooks o³ are tilted to permit the hammer to pass behind them. The
hammer having passed the hooks it is carried slightly beyond to strike and lift the
outer end of the trigger and so remove hook p³ from the tail piece of the latch allowing
it to drop to carry the hooks in front of the lever in which position it again becomes
locked by engagement with the shoulder p and will sustain the hammer."
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed I declare that what I claim is :—
1. The method of opening an electric circuit which consists in mechanically
breaking out by a hammer blow, a section of the circuit from between two terminals,
and simultaneously breaking the removed section into a plurality of parts, sub-
stantially as and by the means herein before described and as illustrated by the
accompanying drawings.
2. In an electric circuit breaker, the combination of a breakable bar forming a
section of the circuit and a hammer adapted to strike and break said bar, constructed
and arranged substantially as described and as illustrated by the accompanying
drawings.
3 In an electric circuit breaker, the combination of a breakable bar forming a
section of the circuit, a hammer adapted to strike and break said bar and an electro-
magnet controlling said hammer, constructed and arranged substantially as described
and as illustrated by the accompanying drawings.
4. In an electric circuit breaker, the combination of a breakable bar forming a
section of a circuit, a hammer adapted to strike and break said bar, a latch supporting
said hammer in position to strike, a trigger for releasing the latch and an electro-
magnet whose armature is adapted to operate the trigger, all constructed arranged
and operating substantially as described and as illustrated by the accompanying
drawings.
5. In an electromagnetic circuit breaker the combination of a breakable bar forming
a section of the circuit, a hammer adapted to strike and break said bar, a latch
supporting said hammer in position to strike, a trigger adapted to hold the latch in
its operative position and to release the same, a detent for the latch adapted to hold
it in its inoperative position, and an electromagnet whose armature operates the
trigger, all constructed and arranged substantially as herein before described and as
illustrated by the accompanying drawings.
6. In an electromagnetic circuit breaker, the combination of a breakable bar forming
a section of a circuit, a hammer adapted to strike and break said bar, a latch supporting
said haminer in position to strike, a trigger provided with two detents, one adapted to
sustain the latch in its operative position and the other to sustain it in its inoperative
position and an electromagnet whose armature operates the trigger, constructed and
arranged substantially as hereinbefore described and as illustrated by the accompanying
drawings.
7. In a circuit breaker an electromagnet having a ring, or other closed shaped core
whose arinature space is formed by removing a segment thereof, an armature for said
magnet normally located within said ring, a trigger projecting into the armature space
and adapted to be moved by the armature, a latch controlled by the trigger and a

page_text: circuit controlling device held in operative positive by the latch, substantially as
described and as 'illustrated by the accompanying drawings.
8. In an electromagnetic circuit breaker, an electromagnet having a ring or other
closed shaped core, a segment of which is removed to form the armature, an
armature normally surrounded by said ring, and an adjustable support for the
armature, constructed and arranged substantially as hereinbefore described and as
illustrated by the accompanying drawings.
9, In an electromagnetic circuit breaker an electromagnet having a ring or other
closed shaped core, a segment of which is removed to form the armature space, an
armature located within said ring, a pivoted arm normally supporting the armature and
a ratchet sustaining said arm and along which it is adjustable, substantially as and
for the purpose described and as illustrated by the accompanying drawings.
10. In a circuit breaker, a breakable bar forming a section of the circuit, a spring
operated hammer in the form of a yoke, a cross piece of which is adapted to strike
and fracture the said strip, substantially as herein before described and as illustrated
by the accompanying drawings.
11. An electromagnetic circuit breaker constructed arranged and operating
substantially as and for the purpose herein before set forth and as illustrated by the
accompanying drawings.