Solici
Year: 1897

page_text: Date of Application, 28th Sept., 1897-Accepted, 8th Jan., 1898
(A communication by THORSTEN VON ZWEIGBERGK, of Cleveland, in the County of
Cuyahoga, and State of Ohio, United States of America; Electrician.)
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors, 6 Lord Street, Liverpool, & 6 Bank Street, Manchester, both in the
County of Lancaster, 118 New Street, Birmingham, in the County of Warwick, and
322 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 object of the invention is to provide simple and effective means for transferring
the sparking resulting from breaking a contact, from a controller cylinder where this
sparking is harmful to some point where it is innocuous. The sparking in the
controller wears away the contact plates and fingers, and thus rapidly destroys the
controller. The spark sometimes causes the cnrrent to are over from a contact plate.
to its finger, and thereby defeats the operator's control of his motor. The invention
obviates the spark at the controller, and establishes it between surfaces so large or so
easily replaced that it becomes immaterial,-surfaces which can be separated far
enough to destroy all probability of an arc forming between. them. The invention
consists of a magnetic switch, adapted to be used in conjunction with a controller
and operated by a current governed by the controller, which forms a shunt around
the controller contacts, and, after that contact has become broken by the movement
of the controller cylinder, is itself opened by a further controller movement, and
thereby breaks the circuit between points where the resulting spark is harmless and
where the chance of forming an arc is minimized. The combinations of parts
hereinafter specified and definitely enumerated in the claims also disclose wherein the
invention consists, but the invention is not to be understood as limited to the
particular construction specified further than those claims indicate.
The drawings clearly illustrate the invention and its method of operation.
Figure 1 is an elevation of the circuit breaker and its case, with the case door
removed. Figure 2 is a vertical transverse section of the same being taken on the
line 2-2 of figure 1. Figure 3 is a somewhat diagrammatic elevation of the same,-
being embodied in a cheaper form. This figure indicates also the contact fingers
of the controller, and the development of the controller cylinder. The movable part
of the switch is shown in the position it occupies when the contact fingers are in the
position of contact indicated by the broken line marked 1, in the right hand portion
of said figure. Figures 4, 5 and 6 are similar diagrammatic elevations of the
magnetic switch for the contact positions indicated by the lines 2, 3 and 4 respect-
ively, on the cylinder development in figure 3. Figure 7 is an elevation, similar to
figure 3, of a modified form of circuit breaker, together with the development of the
controlling cylinder corresponding thereto.
Referring to the parts by letters, A represents a box preferably of an approx-
imately cubical shape. This box is made of cast iron or other desired material, and
has feet a at its upper corners by which it is hung from beneath a car or other

page_text: support. A suitable door a¹ closes the box. In the interior of the box, projecting
upward from its bottom, is the magnet core B. This core may be cast integral
with the box or otherwise carried by it, as desired. Secured to the core, preferably
by bolting, is a pole piece having the furcations b and 6¹. Field. coils C surround
the magnet core. Smaller coils D. and. D¹ surround the furcations b and b¹, and
these, because of their operation, are designated armature coils.
E is a metallic armature oscillatably journalled in proper relation to the pole
faces, being preferably sleeved around a large stud e¹ projecting from a boss es,
carried by the case. The winding of the field coils C is continuous, while the
windings on the two pole pieces are opposed to each other, as indicated by the
arrows in figure 3, for example. If now, a direct current flows through the field
coils and armature coils, the current around one of the pole pieces, as 61, will be
the same as that about the core B, while the current around the other pole
piece, as b, will be opposite to that around the core B. The result is that the
magnetisin which would be caused in the pole piece by the field coils is
overcome, while the magnetism of the pole piece 61 is increased. The armature
is, therefore, attracted by the pole piece bl, and oscillates towards it. If the current
through the armature coils is reversed, the pole piece b¹ will be demagnetized and
the pole piece b energized by both. field and armature coils, and hence the
armature will oscillate toward b.
The side of the armature opposite the pole pieces carries a contact knob e, which
is preferably removably, secured to the armature by a screw bolt e² passing. into a
bosses on the armature. Contact pieces are held by the case at each side in suitable
position for the armature knob e to contact with them in either extreme position of
the armature, and thus the armature may break or establish a circuit through itself
and the contact piece, and suitable conductors leading therefrom. These contact
pieces may be made in the form of shoes F and F¹, as shown in figure 1. There
each shoe is carried by a lever G pivoted at g to a platė g¹ secured to the
insulating block g². A spring g³ (secured to the lever and having its free end pressing
against the lug g5 projecting from the plate g¹) presses the shoe towards the
armature, and a stop g' limits its movement in that direction, so that it will be in
position for the armature knob. to easily slide beneath it, while' sufficient pressure is.
afforded by the spring to insure a good electrical contact. When such an arrangement.
of contact pieces is used, it is preferred to form the magnet side of the armature
with two segmental bosses e* and eo, leaving the notch es between thein. The convex
length of each boss is substantially the same as the concave length of the pole face,
while these bosses are formed such distance apart that the length of a boss and the
notch is substantially the same as the distance between the pole pieces.
The result of this construction is that the pole piece which is energized,
say b¹, holds the armature in the corresponding extreme position, resisting
its movement in either direction, and thus forms an electrical stop, dispensing with
the necessity of a mechanical stop; while the other boss, as e, has its corner opposite
the corner of the pole piece b in position to oscillate, the armature in the reverse
direction when the current is reversed.
If desired, the construction may be cheapened by providing siin ple knobs H and H¹,aз
shewn in figures 3 to 6, in place of the spring pressed shoes. These knobs are
stationarily secured by the plates h to the insulating blocks h¹. In such construction
the segmental boss on the 'armature is made to overhang the pole face when the
knob eis against the knob H or H', so that there will be an electrical pull given by
the pole piece which will hold the armature knob in good electrical contact with the
knob H.or H. A simple way to provide for this overhanging, is to make but one
boss, and is of a greater convex length than the concave length of either pole face,
which latter would in that case be preferably placed as close together as is convenient.
in construction. Such an arrangement is illustrated in figures 3 to 6, the single boss.
being indicated by the reference letter e. If desired, this boss may be nothing
more than the rounded end of the armature,

page_text: The construction and specific operation of the magnetic switch, as illustrated in the
first six figures, having been explained, the manner in which it is operated, in con-
nection with the controller, will now be described. In figure 3, a motor is indicated
at M from which the line m leads to the ground or return wire. N and N' indicate
resistances. The controller may direct the current through both of these resistances,
or only one, or, around them both, direct to the motor. This illustrates the manner
in which the controller governs the motor. The controller might be of the series--
parallel type, and govern two or more motors, but for simplicity of illustration, only
one motor is shown, and that governed by means of a variable resistance. Four
positions of the controller cylinder are indicated in the drawing, by the broken lines
marked 1, 2, 3 and 4. The first of these positions is the "off" position; No 2 is the
position where the current flows through both resistances N and N¹; No. 3 through N
alone; and No. 4 where it passes direct to the motor.
The current comes from the trolley to the conductor S, and passes around the
field windings C, and thence by the conductor to the contact finger T. The
reference letters T¹ to T, inclusive, indicate suitably formed contact fingers arranged
in a row parallel to the axis of the controller cylinder, and adapted to contact with the
plates forming that cylinder. These plates, which are secured to the controller body in
the usual manner, are indicated by the reference letters U and u with varying
exponents. The upper three plates, U1, U2, U³, govern the motor. The inter
mediate plates beginning with U³ and ending with U7, and including u to u³,
inclusive, serve to commutate the armature coils and establish the circuit through
them in the desired direction. The lower plates uº, U³, Uº and U10 operate in com-
pleting the circuit from the circuit breaker to the motor.
The contact finger T is always in engagement with the contact plate U. Let it
be supposed that the contact plates and fingers are in the relative position indicated
by the broken line in the development in figure 3, which is one of the terminal
positions of the controller,-the "off" position.
The plate U4 is permanently electrically connected with the plate. U³, as indicated
by the line 2. The circuit thus leads to the plate U and through the contact
finger T to the conductor 84, by which it continues to the armature coils D1 and D,
and from which the conductor 80 carries it back to the contact finger T and the
plate U. From the plate U the circuit passes through the connection, the
plate U, the contact finger T, and the conductor 87, to the contact piece H¹ or F¹ of
the magnetic switch. But the armature of the switch hangs by gravity in its middle
position, and out of contact with either of the contact pieces. The circuit is broken
at H or F, and no current passes. If for any reason it should be in contact with
Hor F, the current passes through the armature and the conductor 83, and through
the resistances N₁ and N, and the motor to the ground. But before the motor can
have time to move, under the action of this current, the armature coil D¹ of the
magnetic switch has caused the armature to be swung away from H¹ or F¹, and the
circuit opened. Thus no operative current flows when the controller is in the "off."
position, while this position always causes the armature to stand away from the
contact piece H¹ or F¹. Figure 3 shows the armature just after it has swung away
from the current having been flowing from 87 to 83 as indicated by the arrows.
In order that the illustration may be logical, an arc R is shown as completing the
circuit, but in practice only a spark will be formed and the current will cease to flow
when the armature is moved away from the knob H¹. The impulse given to the
armature by the coils D¹ may not be sufficient to swing the end e clear over the
knob H, but, whether it does or not, no circuit is formed at this time through H,
and the armature comes to rest in a vertical position, midway between the knobs H
and H¹,
If, now, it is desired to start the motor, the controller is turned one notch to bring
the contact plate and fingers into the relative position indicated by the broken line 2.
Just as the contact finger T3 contacts with the plate U³, the circuit is established
from the trolley and plate Us by to plate ³, thence via contact finger T
conductor so, around the armature coils in reverse direction and back by s to plate w

page_text: connection v, plate U³, to contact.finger T3, and from T3 through the resistances N¹
and N to the motor and ground. The current thus started energizes the pole piece b
and swings the armature into contact with the knob H¹. A shunt is thus established
from U³ via vs, plate U7, finger 17, conductor 87, knob H', armature E, conductor 83
and the resistances, as indicated in figure 4. As the contact finger T7 passes off of
the plate U7, as the controller comes to position 2, this shunt is broken at that point,
but the armature remains in the same position, as the main circuit is already
established around the armature coils.
In position No. 3 the circuit extends from the trolley to plate Us, thence via v³ to u¹,
thence to contact finger T, and around the armature coils in the opposite direction
from the course it took in the preceding position; thence via conductor 8 to plate ut,
thence by the connection 27 vs to plates U³ and U2. Part of the current passes
from U2 through the single resistance to the motor, a small part from U³ through
both resistances to the motor, while, the armature having been swung by the coils D¹
into contact with the knob H, a part of the current shunts through the conductor s³,
the armature, the knob H, conductor 89, to plate U, connection 10, plate U8,
connections 8 and 82 to the motor. This leaves the switch in the position shown in
figure 5.
When the controller has been turned to its terminal position, as indicated by the
broken line 4, the current passes from the trolley to U³, as always, from there via
connection to plate us, and by the conductor 86 around the armature coils in the
reverse directions again, to conductor 84 and from thence to plates u² and U³, thence
via connection to plate U¹ and to the motor direct,-immaterial shunts being also
formed from U2 through the resistance N, and from U³ through both resistances N¹
and N. The armature having been swung by the coils D into contact with the
knob H when the fingers T and T6 passed from the plates u¹ and u to the
plates u² and us, a shunt is also formed through the circuit breaker, as indicated by
the arrows in figure 6. The current flows through this circuit from U³ to 63, and
through the armature to H¹, and from H¹ by 87, u, v, U10, 810, and 81 to the motor,
thus leaving the switch in the position shown in figure 6.
It will thus be seen that the circuit breaker does not interfere in the least with the
governing of the motor by the controller. When the controller is turned a notch
from position 4 to position 3, without the use of a circuit breaker attachment, the
only path for the current which has been flowing direct to the motor is by the
previously formed shunt through the resistance Ñ. This sudden interposition of
resistance to the whole current, breaks down the current and a spark is formed
between the plate U¹ and the contact finger T¹. This spark is not as large as it
would be if there were no shunt established through the resistance, but it is enough
to be deleterious. With this attachment, a shunt is formed around the contact
between T and U¹ while they are in position 4, by the circuit breaker, which, it will
be remembered, was swung into the position indicated in figure 6 when the controller-
moved to the said position No. 4. This shunt, as stated, passes from U³ to the
armature E, thence to the knob H¹, thence via 87, T7, u, v, U10, T10, 810, and 8', to
the motor direct. Hence, when the contact finger 11 leaves the plate U¹, no spark
will be formed, as the shunt through the circuit breaker is of substantially as low
resistance as the path previously provided. When the contact fingers T and T
withdraw from the plates u² and us to the plates u¹ and ut, as the controller continues
its movement toward position 3, the current is reversed in direction through the
armature coils, the armature oscillates, and the circuit is broken between e and H',
where the spark is harmless.
This leaves the current flowing to the motor through the resistance N, both
directly from the plate U2 and from the plate U³ via the shunt through the circuit
breaker. When the finger T2 leaves the plate U2, no spark is formed, as the circuit
breaker shunt carries the current. This shunt is again broken with a spark
between H and e as the fingers T and To pass from plates u¹ and u to plates u
and u³.
As the finger T leaves the plate U³ in passing from position 2 to the "off"

page_text: position, a large spark would ordinarily be formed since there would be no shunt, even
through resistance, provided in this case, both resistances being in series with the
motor. But with the attachment herein described, a shunt through the circuit
breaker has already been formed (via u³, Tº, 8º, 84, u, U³, v³, v7, U7, T7, 87, H¹, E, 83, N¹
and N) and this receives the current. When the fingers T4 and 1 pass from the
plates u and u³ to the plates U and U, the direction of the current through the
armature coils is changed, and the circuit is thereby broken between H¹ and e, and
thus the spark takes place between these large knobs where it can do no harm. The
current now stops and the controller cylinder assumes the "off" position indicated
by 1, the armature E hanging midway between its extreme positions.
The circuit breaker shown in figure 7 accomplishes the same result as that produced
by those which have been just described, and in some cases may be deemed prefer-
able. Here, instead of the armature oscillations being caused by a reversal of current
around pole pieces of a single magnet, two magnets are employed and the current
flows entirely through one and then entirely through the other. In this arrangement,
two horse shoe magnets, each having but a single coil, as shown in the drawing, are
preferably employed. One magnet is composed, as shown, of the core 62, 63, 64, 66 and
the coil D², and the other of the core 63, 67, 64, 68 and the coil D³, the post 6 and the
proximate portions of the double base piece b5 67 and the double pole piece 66 68 being
thus common to both magnets. E' represents the pivoted armature, e and e¹o the contact
knobs carried thereby, and F2 and F3 contact shoes with which the knobs contact.
M¹ represents the motor, m¹ the ground or return wire, and N2 and N3 resistances.
The contact fingers are indicated by T¹ to T23 inclusive, the corresponding circuit
connections by S11 to S28 inclusive, and the contact plates of the controller by U"
to U2 inclusive, and u, u18 and 23. The upper five rows of contact plates are con-
nected together by the connection vil, the three middle rows by the connection v12,
and the lower five rows by the connection 13. With the connections as shown, the
upper bank of contact plates governs the motor, the middle bank the magnetic switch,
and the lower bank completes the shunt connection.
The construction indicated in figure 7 having been explained, the operation thereof
will now be briefly described, it being supposed that the controller is being withdrawn
from position 4 to position 1, i.e. from the position at full speed to the "off"
position.
In position four, the current passes, as always, along conductor S17 to the contact
finger T, to the plate U. From thence the current travels via connection v12 to
contact plate u", thence to contact finger T18 thence via conductor S18 to coil D²,
thence via conductor S15, contact finger T15, plate U1, connection to the contact
plate U¹¹, and thence to contact finger T₁ and conductor S direct through the
motor M¹ to the ground or return wire m'. The magnet D² is thus energized and its end
of the armature E' drawn down, causing the contact knob eo to impinge against the
shoe F3, thus connecting the conductor S with the conductor S23. No complete
circuit is established, however, as the contact finger T23, at which the conductor S23
terminates, is not in contact with any plate. When the controller cylinder is turned
from position four to position three, however, the first result is that the contact
fingers T1 and T23 contact with the plates U21 and 23. This completes a shunt
circuit from the plate U15 via connection, plate U14, contact finger T", conductor S14,
armature E', knob e¹0, shoe F³, conductor S³, contact finger 123, contact plate u³³,
connection v13, contact plate U2, contact finger T21, conductor S" to contact
finger T, where it joins the main circuit. This shunt circuit is thus established
when the contact finger T passes off the plate U" and the contact finger T¹² passes
onto the plate U12, and therefore no spark results. When the contact finger T18
passes off the contact plate 18 and the contact T1 passes onto the plate u¹0, the
coil D² is cut out and the coil D³ cut in, thus causing the armature to oscillate and
the shunt circuit to be broken.
Before a contact finger T12 leaves contact plate U12, a new shunt is established from
plate U15 to plate U, to conductor S", to the armature and through knob e' and
shoe F to conductor S20 and from thence to the plate U", from thence to plate Ụ¹º

page_text: and via conductor S10 to contact finger T, where it joins the main circuit to the
motor through the resistance N². As contact finger T1 passes off the plate u16, and
contact finger T18 passes onto the plate US, the magnet D³ is cut out and that of D2
is cut in. The armature is again reversed breaking the circuit between the knob e
and the shoe F2. Before the contact finger T13 passes off the plate U13, a shunt is
established through the circuit breaker and the two resistances, by means of the
contact plates U and U23 and the corresponding conductor and connections, and this
prevents the spark otherwise resulting between contact finger T¹³ and contact plate U13.
When contact fingers T1 and T18 come onto the plate U16 and leave the plate U18
respectively, the armature is again reversed, swinging into the position shown in
figure 7, and the current is broken between the knob eo and the shoe F³, where the
spark will do no harm.
It will thus be seen that the operation of this modified form of circuit breaker is
substantially the same as that herein before described.
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 :-
1. The method, substantially as herein described, of obviating the sparking at a
controller contact when broken.
2. In a controller circuit breaker, the combination of a magnetic switch, a controller
having plates and contact fingers adapted to govern the current through the motor,
and plates and contact fingers adapted to govern the current through said switch,
said last mentioned plates and contact fingers being adapted to be separated by the
movement of the controller at a different time from that when the first mentioned
plates and contact fingers are separated by said movement, whereby a shunt is
established through the magnetic switch around the motor-governing contact about
to be broken, which shunt continues until after said contact is broken and is then
itself broken by the movement of the controller, substantially as described.
3. The combination with a motor and a magnetic switch, of a controller having
co-operating contact members consisting of a series of contact fingers and a series
of contact plates, there being provision for relative movement between said two
series, conductors leading from one series to the magnet or magnets of the switch,
to the contact points of the switch and to the motor, whereby some of said contact
members are adapted to govern the motor, others to govern the magnetic switch, and
others to properly complete a shunt circuit through contact established by said
switch, substantially as described.
4. The combination of a controller having contact fingers and plates adapted to
come into different relations, a motor, a circuit-breaker including a magnet and
armature, and a circuit extending from the controller through the magnet of the
circuit-breaker and back to the controller, and then dividing to the motor by two
paths, one of which includes a movable part consisting of or operated by the
armature of the circuit-breaker, said controller being adapted in its movement to open
first the direct path to the motor, and then to electrically open the path through the
circuit-breaker by means of the movement of the armature caused by an electric
change in the magnet, substantially as described.
5. The combination of an electrically operatable circuit-breaker with a controller
having a series of contact fingers and contact plates of various lengths or positions
adapted to be engaged thereby, some of said contact plates governing a motor and
others of them the circuit-breaker, the relative termini length or position of the
motor-governing plates and the circuit-breaker-governing plates being such that in
the movement of the controller the motor plate-fingers and the circuit-breaker-plate
fingers leave their respective plates alternately, substantially as described.
6. The combination with an electrically operated circuit-breaker, of a controller
having a series of contact fingers arranged in a row, and a series of contact plates
secured to a body which is adapted to come into different relative positions with the
contact fingers, some of said contact plates governing the machine to be controlled,

page_text: and some the circuit-breaker, the former plates being so placed that each of their
contact fingers engages with but one plate and the several contact fingers are adapted
to leave the several plates one at a time, and the latter plates being so placed that
one circuit-breaker-governing contact-finger is adapted to contact successively with a
plurality of plates, substantially as described..
4
7. In a magnetic switch, the combination of a magnet core having continuously
wound field coils surrounding it and two pole pieces projecting from. it, armature
coils surrounding the two pole pieces in opposite directions, and an "armature
oscillatably journalled in suitable relation to the pole pieces, substantially as
described.
8. In a magnetic switch, a magnet core having continuously wound field coils
surrounding it, and two pole pieces projecting from it, armature coils, surrounding
the two pole pieces in opposite directions, and an armature oscillatably journalled in
suitable relation to the pole pieces, combined with a controller adapted to govern a
machine by breaking contacts and adapted to change the direction of a current
through the armature coils at times which are intermediate of the governing breaks,
substantially as described.
9. The combination of a circuit-breaker including two contact pieces, an armature
and coils adapted to electrically draw the armature into contact with either contact
piece by a change of the current through the coils, and a controller adapted to
govern a machine and cause such a change of the current through the coils,
substantially as described.
10. The combination with a controller consisting of co-operating contact members,
of a circuit breaker, including two contact pieces, an armature, and coils adapted to
electrically draw the armature into contact with either contact piece by a change of
the current through the coils, and conductors leading from said armature, from said
contact pieces and from said coils to contact members of the controller, whereby said
controller is adapted to govern a machine, to cause a change in the current through
said coils and to complete a circuit through said armature, substantially as
described.
11. The combination with a circuit-breaker of a controller adapted to govern a
motor and having plates and corresponding contact fingers substantially as shown, for
governing the circuit-breaker, there being connections substantially as shown between
the controller and the circuit-breaker, substantially as described.
12. The combination with a circuit-breaker of a controller having plates and
corresponding contact fingers, substantially as shown, for governing a motor and
plates, and corresponding contact fingers, substantially as shown, for governing the
circuit-breaker, substantially as described.
13. The combination with a controller of a circuit-breaker interposed in a shunt
circuit around said controller, said controller having plates and corresponding contact
fingers, substantially as shown, for governing a motor, and plates, and corresponding
contact fingers, substantially as shown, for completing the circuit through the
circuit-breaker, and means for governing the movement of the circuit-breaker,
substantially as described.
14. In a magnetic switch, the combination of the magnet core B, the field coil C,
the pole pieces b and b¹, the armature coils D and D¹, the armature E carrying the
knob e, contact pieces with which said knob is adapted to contact in either extreme
position of the armature, and conductors connected with the contact pieces and the
knob, substantially as described.
15. In a magnetic switch, the combination of the box A, the core B and the boss €8
formed integral with the walls of said box and extending inward at substantially
right angles to the same, pole pieces extending from said core, a stud e¹ extending
from said boss, an armature mounted on said stud, and having a rounded end adapted
to stand close to the face of the pole pieces, and means for electrically energizing
said pole pieces, substantially as described.
16. In a magnetic switch, the combination of pole pieces having concave faces, an
oscillatable armature having a rounded end and suitably journalled with reference to

page_text: said pole pieces, means for stopping the oscillation of said armature in either
direction, and thus providing an extreme position, contact pieces with which said
armature contacts in either extreme position, conductors leading from said armature
and contact pieces, and means for electrically energizing the pole pieces and thereby
making or breaking a circuit through the armature and a contact piece, substantially 5
as described.