Improvements in Switches or Relays for Use with Alternating Currents, also applicable to Vibrators.
Year: 1893

page_text: Date of Application, 12th Dec., 1893
Complete Specification Left, 6th Sept., 1894-Accepted, 12th Dec.,
1894
PROVISIONAL SPECIFICATION.
Improvements in Switches or Relays for Use with Alternating
Currents, also applicable to Vibrators.
I, HERMANN ARON, of 6 Lützowstrasse, Berlin, in the Kingdom of Prussia,
Doctor of Philosophy and Professor, do hereby declare the nature of this
nvention to be as follows:-
My invention relates to an improved relay (relais) for alternating currents
which overcomes the difficulties existing in the application of a magnet of usual
construction to alternating currents for making a contact aud closing a circuit.
The aforesaid difficulties are, firstly, that the contact is not constantly closed,
This fact
but vibrates according to the number of alternations of the current.
may be observed even if the iron be divided, and though the vibrations thereby
are considerably abated, yet their existence is still very objectionable, it may
partly be attributed to eddy currents arising in the armature, which eddy currents,
together with the magnetising current, act to repel the armature and thereby
periodically interrupt the contact. Another difficulty exists in the fact that a
counter-electromotive force is produced by the great number of turns which, for
instance, are required in a central station to operate the relay for connecting a
recording instrument with but one lighted incandescent lamp, said counter-
electromotive force reduces the useful potential at the lamps, while the electro-
magnet is fully excited.
My invention consists in arranging two magnetic fields vertically upon each
other and placing a closed copper ring within said fields, the plane of the turns of
Baid ring being so located that the lines of force of one of the said fields are directed
vertically to the said plane, while the lines of force of the other field are directed
parallel to the same.
One of these magnetic fields is obtained by a coil of many turns, connected in
shunt with the lamps and, accordingly, traversed by an alternating current of
constant strength. This magnetic field produces, within the said copper ring, an
induced current, which, together with the other magnetic field, produces a motive
power with the tendency to turn the said ring in such direction that the lines of
force of the said ring will coincide with the lines of force of the other magnetic
field. To obtain the contact, it will not be necessary to give the said ring a full
quarter of a turn.
The other coil is connected in the lamp circuit. The magnetic field produced
by this coil is proportionate to the strength of current by which the contact is
closed, and, accordingly, proportionate to the pressure of said contact.
In carrying my invention into practice, I arrange the one coil with many turns
on one side of a closed square iron ring, on the opposite side of said iron ring a
This copper ring
square copper ring is arranged to turn readily on a centre.
carries an arm, which, when pressing against a contact screw, closes the circuit.
To the other side of the said copper ring, a spiral spring is secured, which leads
the current from a binding-screw to the said ring, and also returns the said ring
and arın to their normal position. The other coil of strong wire is mounted on a
U-shaped iron core, the poles of which embrace the copper ring on both sides,
being so shaped that the sides of said copper ring, while the latter is turning, are
kept in close vicinity to the said poles.
The copper ring may be constructed of a number of thin sheets, insulated from.
each other. By this means, I prevent eddy currents which might arise within the
said conner ring.

page_text: If the arrangement described is to be used to cause an existing contact to
vibrate, instead of for closing a contact, the U-shaped magnet with its coil may be
replaced by a permanent horse-shoe-magnet; in this case, the copper ring, under
the influence of said permanent magnet, will vibrate and transfer its vibrations to
the contact..
Dated this 11th day of December 1892
WM. P. THOMPSON, & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Switches or Relays for Use with Alternating
Currents, also applicable to Vibrators.
1, HERMANN ARON of 6 Lützowstrasse, Berlin in the Kingdom of Prussia,
Doctor of Philosophy and Professor, 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:-
My invention relates to an improved switch or relay for alternating currents,
which overcomes the difficulties existing in the application of a magnet of usual
construction for obtaining, with alternating currents, a motion, such as for making
a contact and closing a circuit. The aforesaid difficulties consist, first, in that the
contact is not constantly closed, but vibrates, according to the number of
alternations of the current. This fact may be observed even if the iron be
divided, and though the vibrations, thereby, are considerably abated, yet their
existence is still greatly objectionable, it may partly be attributed to eddy currents
arising in the armature, which eddy currents, together with the magnetising
current, act to repel the armature and thereby periodically interrupt the contact.
Another difficulty exists in the following circumstance. If the switch or relay
be employed for instance to connect a recording instrument for measuring the
amount of electricity delivered to a subscriber, it is desirable that the said instru-
ment should be capable of measuring the electricity consumed not only when a
single lamp is burning, but also when a number or all the lamps are in use.
In employing, for such purpose, a switch or relay, the coil of which has but a
small number of turns, the said switch or relay will fail to connect the recording
instrument, when only a single lamp is lighted, because the attraction produced by
the current taken by lamp is not sufficient to connect such instrument in circuit.
Accordingly, it has been necessary to employ a switch or relay with a coil
having a great number of turns; but this is equally objectionable. The alternating
current, flowing through the coil of the switch or relay produces therein an induced
current which, if only one lamp be lighted, will be comparatively small; but if all
the lamps be lighted, the self-induction caused by the large current passing through
the switch or relay will be so much increased as to considerably reduce the voltage
at the lamps.
My invention consists in arranging two magnetic fields vertically upon each
other and in placing a closed copper-ring within said fields, the plane of the turns
of said ring being so located, that the lines of force of one of the said fields are
.directed vertically to the said plane, while the lines of force of the other field are
directed parallel to the same.
In the accompanying drawings,
Figure 1 is a perspective view of the complete arrangement of the switch or
relay;
Figure 2 is a plan of the iron ring and core & in combination with the pivoted
finger f;
Figures 3 and 4 are diagrams showing the connections of the current.
13

page_text: Figure 5 illustrates the connection of an apparatus for measuring electric
currents to the line circuit by the switch or relay hereinafter described.
Figure 6 illustrates the arrangement of the switch or relay when adapted for
ransmitting the electrical undulations of telephones and microphones.
turns,
One of the said magnetic fields is formed by the coil a of a great number of
said coil being connected in shunt with the lamps and accordingly an
alternating current of constant force flows through said coil. This magnetic field
produces within the copper-ring d an induced current, which, together with the
other magnetic field, obtained by the coil b produces a motive power with the
tendency to turn the said ring d in a direction to make the lines of force of the said
ring d coincide with the lines of force of the said other magnetic field.
To obtain the desired contact of the finger f, it will not be necessary to give the
said ring d a full quarter of a turn. The other coil b is connected in the lamp
circuit. The magnetic field produced by this coil b is proportionate to the strength
of current and accordingly, also proportionate to the pressure by which the contact
is closed.
In carrying my invention into practice, 1 arrange the coil a, on one side of a
square iron ringe and on the opposite side of said iron ring e, a square copper
Said copper ring d, carries an arm f
ring d is placed, turning readily on a point e.
which, when pressing against a contact screw g, closes a shunt or secondary circuit.
To the other side of the said copper ring d, a spiral spring his secured, which leads
the current from a binding screw i, to the said ring d and also returns the said
ring d and arm f to their normal position. The other coil 6 of strong wire is
mounted on a U-shaped iron core k, the poles of which embrace the copper ring d
on both sides, said poles being so formed that the sides of the copper ring d, while
the latter is turning, are kept in close vicinity to the said poles, as shown in
Figure 2.
1
The connection of the series and shunt coils of this improved switch or relay, in
The path of the current for
the main lamp circuit is illustrated by Figure 3.
connecting an instrument for recording the amount of energy delivered, as an
example, is shown in Figure 5, in which D is the dynamo, the current of which
passes from one of the brushes to the coil A connected in series with the lamps L.
Above said coil swings the pendulum belonging to the clock-work to be influenced
by the current. The said pendulum carries a coil B, connected in shunt to the
lamps, the current flowing through said coil B being proportional to the voltage at
the lamps.
From the coil A, the current flows to a terminal C, of the switch or relay and
from thence has three courses, first, to the coil b, second to the coil a, and third, to
the binding-screw i, of the ring c.
From the coil b, the current flows to the lamps L. The other end of coil a is
connected, with one end of coil B, and with the coil F of a mechanical driving
mechanism, and finally to the return wire of the lamps.
The other end of coil B, and the other terminal of the driving-mechanism are
connected to the contact-screw 9.
Supposing now, that one or more lamps are lighted, the main current in coil b
together with the shunt-current of the coil a operates to turn the copper ring d, as
described, and thereby the finger makes contact with the screw g. Now, the
current can pass through the driving coil F, as also through the measuring coil B,
in shunt to each other. The coil sets in motion the two clock-works of the
0 meter, and the attraction established between the coils A and B by the currents
passing, causes the deviation of one clock-work relative to the other running at
normal speed. The deviations of the two clock-works are recorded to measure the
electrical energy consumed. This mode of connecting, however, is only necessary
with currents of great energy, with currents of small energy both coils a & b may
5 have the same winding of wire and may be connected in series in the same circuit,
as indicated by Figure 4.
The said copper ring d may be constructed of a number of thin sheets of copper,

page_text: '
insulated from each other. By this means I prevent eddy currents which might
arise within the said copper ring.
If the switch or relay is required to cause an existing contact to vibrate,
instead of for closing a contact the U-shaped magnet k with its coil b should
be replaced by a permanent magnet or by an electro-magnet with continuous
current, preferably in the horse-shoe shape; in this case the copper ring d, under
the influence of said permanent magnet, will vibrate and transfer its vibrations to
the contact.
By this means I obtain a relay vibrator for transmitting the electrical undulations
of telephones and microphones.
A general arrangement of this kind is 'illustrated by Figure 6. M is a
microphone, P¹ the primary induction coil belonging thereto, E' the primary
:battery. The current induced by the vibrations of the microphone in the
secondary coil B³, flows through both coils of the relay vibrator R connected in
series and effects the movement of the copper-ring d, the armf of which makes and
breaks the circuit of a local battery E, the undulations of which correspond to
those of the secondary or induced current of the coil P' and relay vibrator R.
This vibrating current of the battery E' passes through the coil P³ and induces
within the coil P an alternating current of the same frequency, as that flowing
through the coil P³, thereby reproducing in the telephone T the sounds transmitted
by the microphone M.
'
By this means the current of a microphone may be transmitted to any distance,
as is the case in telegraphy.
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. A switch or relay for alternating currents, having two magnetic fields vertical
upon each other and a copper ring so arranged within said magnetic fields, that the
plane of its turns in the normal position, is coincident with the direction of the
lines of force of one of the said fields, whereby the current induced within the said
copper ring by the other field causes a deflection of the said copper ring, thereby
causing a contact to be closed, substantially as and for the purpose set forth.
2. A switch or relay for alternating currents, consisting of a coil a, mounted on
an iron ring c, and forming a magnetic field, a copper ring d arranged to turn and
having an arm fand a return spring h, another coil 6 mounted on a U-shaped iron
"core and a contact g against which the said finger bears to close the circuit under
the influence of the two magnetic fields, substantially as and for the purpose set
forth.
3. A switch or relay for alternating currents, consisting of a coil a mounted on
an iron ring c and forming a magnetic field, a copper ring d arranged to turn and
having an arm f and a return spring ha permanent magnet or continuous electro-
magnet forming another magnetic field, and a contact g against which the said arm
bears to cause vibrations of the existing contact, substantially as and for the
purpose set forth.
Dated this 5th day of September 1891
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.