AN IMPROVED APPARATUS FOR REGULATING AND CONTROLLING ELECTRIC CURRENTS to
Year: 1885

page_text: I, ALFRED GRUNDY Electrician of Amberley Works Amberley Road Paddington,
Middlesex do hereby declare the nature of my invention for AN IMPROVED
APPARATUS FOR REGULATING AND CONTROLLING ELECTRIC CURRENTS to, be as
follows:-
A series of permanent or electro magnets being acted upon partly by the main
current and partly by a shunt current from either the generator or accumulator or
from both shall according to the preponderance or variation of potential or current
from either the generator, accumulator or other part of the circuit make or break
the connection. between them.
To enable me to do this I use in the main circuit a horse shoe electro magnet
wound with two helices of thick wire in opposite directions.
One winding being connected between the terminals of the lamp circuit, or those
of the accumulator and the other between the terminals of the dynamo or other
generator of electricity.
The soft iron cores of this horse shoe electro magnet are connected together by
being secured to the end of a bar magnet bent in the shape of an "L" which may
be either a permanent or electro magnet if it be an electro inagnet its coil may be
inserted either in the main or in a shunt circuit.
The free ends of the cores of the horse shoe electro magnet so long as no current
is flowing round them will by induction from the bent bar magnet whether the
same be a permanent or electro magnet exhibit a magnetic polarity of the same
kind as that end of the bent bar magnet to which they are attached.
At right angles to the other end of the bent bar magnet is pivotted an armature
also of soft iron so arranged as to work evenly between the free ends of the cores
or pole pieces of the horse shoe electro magnet.
This armature will again by induction exhibit a magnetic polarity similar to
that end of the bent bar magnet to which it is attached and dissimilar to that of
the free ends of the cores or pole pieces of the horse shoe electro magnet between
which it is to work and will consequently be attracted by either of the pole pieces
indifferently but most strongly to that one to which it lies nearest.
ה...מ

page_text: Parts of this armature are also made parts of the circuits of the two coils of the
horse shoe electro magnet and it is provided with suitable stops or contact points
for making or changing the connections.
The coil in connection with the accumulators is so wound that on the passage of
a current round the cores of the electro magnet in a certain direction one of the
poles viz: that to which the armature has been originally attracted shall have its
magnetism intensified whilst the other becomes neutralized and in time reversed
thereby exerting a repellant force on the armature and assisting the other pole to
hold it tightly over against the stop to which it was at first connected the charging
circuit being now open.
The coil in connection with the generator being wound in the opposite direction
will have an exactly opposite effect so that on the potential of the generator
becoming sufficiently high the magnetism of the horse shoe electro magnet will be
reversed the pole which hitherto attracted the armature will have a repellant force
and that which formerly repelled will now attract it and it will be moved to the
opposite side completing the charging circuit by coming in contact with a stop for
that purpose.
Should the leads from the generator be wrongly connected the current through
the coil being in the same direction as that from the accumulators would intensify
its effect and it would be impossible to make the charging connection until one of
the currents were reversed.
Should the potential of the generator be equal to but not exceeding that of the
accumulators the electro magnetic properties of the pole pieces being acted upon
by two equal currents in opposite directions would be neutralized and they would
revert to their original condition of soft iron and would exhibit at their free ends
the induced polarity from the bent bar magnet as if no current was flowing.
To prevent the too rapid discharge of the accumulators before the switching on
takes place and to guard against damage to the generator while working in short
circuit with the instrument I employ in each circuit a suitable resistance which is
automatically cut out as soon as the instrument begins to act.
Should it be desirable to ensure the instrument to break the charging circuit
'with a very small fall of potential and the instrument in its simple form be found
not sufficiently sensitive to act within fine limits I place in a shunt circuit with
the main instrument another of a similar type but wound with finer wire and
altogether more sensitive so that any deviation from the potential for which it may
have been adjusted will cause it to act as a relay and so close a local circuit and
assist the action of the main instrument.
Or I may if I prefer it use in the shunt circuit an instrument of the galvano-
meter type the needle or pointer of which by making contact with adjustable stops
will make the necessary connections in the local circuit, the current in which local
circuit may be either an independent one or derived from the accumulator or
generator as preferred.
Again I may if I prefer it dispense with the polarization of the first mentioned
apparatus in the main circuit and substitute for it a simple electro magnetic contact
switch the position of which shall be controlled by the action of the second
instrument in the shunt circuit whether I use the polarized instrument or the one
of the galvanometer type.
The fall of potential in the generator on causing the instrument to act may if
desired instead of at once disconnecting the charging circuit be made to act upon
a combination of wheels or levers or both and thereby open the valve of a steam
engine or sluice valve of a water motor or by other means increase the power of the
generator.
•
I may also arrange that on the charging circuit being broken the steam, gas,
water, or other source of power may be cut off from the motor, or a set of belt
shifting gear or other apparatus be set in motion so as to deprive the generator of
its motive power.

page_text: For facility of working I affix to the base board or other convenient part of
the apparatus switches and current reversers for manipulating the currents at will.
The above arrangement or a combination of parts of it may also be used as a
governor for a motor supplying electricity for.any purpose even when accumulators
are not used.
Dated this 19th of NL 100K
An Improved Apparatus for Regulating and Controlling Electric
Currents.
I ALFRED GRUNDY Electrician of Amberley Works Amberley Road Paddington
Middlesex 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 this invention is primarily to provide an instrument which being
inserted in the circuit of an electric generator when being used for charging an
accumulator or secondary battery shall ensure
1st. That the charging current is in the right direction.
2nd. That it is of a sufficiently high potential to ensure safe charging.
3rd. That in the event of the potential of the generator approaching nearer
than within a pre-arranged limit or falling below the potential of the accumulator
whether by the slipping of a belt slackening of the speed of the motor defect in
the generator excessive rise of the potential of the accumulator, or any other cause
the instrument shall certainly and automatically disconnect the generator from the
accumulator and at the same time (without disconnecting the instrument) shall
automatically insert a resistance in each circuit. And shall further more as soon
as the generator attains a sufficiently high potential at once reconnect the charging
circuit.
Although the foregoing are the primary objects for which the instrument has
been designed it will be evident from its construction and principle that it need
not be limited to that purpose only but may be so arranged that the varying
potential may instead of or in addition to disconnecting the charging circuit be
inade to act (by means of suitable armatures or electro magnets in connection with
levers cranks or ratchet wheels) upon the throttle or supply valve or valves of the
prime motor and so admit more steam gas water or whatever may be the source of
the motive power and so long as the principle of the invention is not departed
from it may be used in any or every position to which experience may prove it
adapted so far as regulating and controlling electric currents is concerned,

page_text: The principles on which this invention is based are combinations of the
following well known magnetic and electro magnetic properties (viz):-
1st. That the free ends of a magnet (permanent or electro) of whatever shape
exhibit two distinct and separate magnetic polarities And that any pieces or parts
of magnetisable metal attached to or resting upon or near either of those free ends
will by induction exhibit at their free ends a similar polarity to that to which
they are attached or are resting upon.
2nd. That like magnetic poles repel and unlike poles attract each other.
3rd. That an electro magnet having two legs or cores attached to each other by
a magnetiseable material and wound as an ordinary horse shoe electro magnet
will on the passage of an electric current have one of its poles north and the
other south.
4th. That a second helice wound on the same cores having an equal length and
resistance and an equal number of turns to the first but wound in an opposite
direction (or as it is sometimes called differentially) will on the passage of a
current of equal potential through its coils neutralize the magnetic effect of the
first coils and the free ends of the horse shoe magnet will revert to their original
nonmagnetized condition.
And that by increasing or diminishing the potential and consequently the
current in either coil either of the poles may be made north or south at will.
Combining laws 1 and 2 and placing a bar electro magnet on a base of soft iron
the outer edge of which forms the connection between the cores of a differentially
wound horse shoe electro magnet and attaching to its upper end or poles a steel or
iron armature of suitable shape so that it shall have its free end lying between
the free ends of the cores of the horse shoe electro magnet but not touching either
of them the whole forms nearly a magnetic square and by induction the free ends
of the pole pieces of the horse shoc electro magnet will exhibit a polarity different
to that of the free end of the armature which will be attracted by both of them
equally and indifferently but by adjusting it originally nearer to one than the
other it will then ponderate in favour of that one to which it is nearest.
Combining with the foregoing the effect set forth in laws 3 and 4 and supposing
the current through the first coil to make the polarity of the core to which the
armature lies nearest of the same name and kind as it was originally by induction
and the other core of an opposite kind and name now by law 2 the armature will
be more strongly held by the first and the second will have a repellant action the
armature being thereby held firmly in position.
When however a current of equal strength is sent through the second or
differential coil the electro magnetism produced by the first will be entirely
neutralized and the free ends of the cores will exhibit only their original induced
magnetism The armature still however remains in its first position.
1st. Because of its lying nearest to the core to which it was attracted and being
somewhat out of the magnetic field of the other.
2nd. Because of its own inertia and friction it will not move without power.
being exerted upon it. Let now the current through the second coil be increased
which would be the case if the electro motive force were increased (Vide Ohms
Law) now the induced magnetism of the first core which has hitherto been
attracting the armature will be partially or totally neutralized and in time
reversed while that of the second core will be strengthened and become more
unlike the armature. The attraction of the first being neutralized or turned into
repulsion and the attraction of the second being increased the inertia and friction
of the armature will be overcome and it will move into a new position. These
movements of the armature are intended by suitable mechanical and electro
magnetic appliances to make the necessary alterations in the connections or to
move the necessary parts for obtaining the desired effect.
Having so far laid down the rudimentary principles on which the action of the
invention is based I will now with the aid of the accompanying drawings proceed

page_text: •
to describe my method of combining these principles in my improved apparatus
for regulating and controlling Electric Currents.
In Fig. I, o. o. is the base board having suitable terminals or binding screws and
mercury or other contacts the apparatus being suitably mounted upon the same―
p is an electro magnet- so wound with a helice of fine wire that a positive
electric current flowing from b+ through m. c to b - will make the upper end s a
south pole and its lower end a north pole The lower end of the core is attached
at.z. to the outer edge of a plate of soft iron l. n. At the other outer edge of 1. n."
on the side n. are connected two soft iron cores c c¹ forming with the connecting
part of 7. n. between them a horse shoe electro magnet. This horse shoe electro
magnet is first wound with a coil of thick wire in such a direction that a current
passing. from m + to m - and entering at c shall make the poles c¹ & c a north
and south pole respectively It is also wound with two fine wire coils wound
differentially so that a current through one of them from 6+ to b- shall
a north pole while a current from m + to m will make ca
-
make c
south pole.
The upper end of p being south the edge of 1. n. will be north at n and conse-
quently the cores c c¹ will also be north when no current is passing through their
coils.
The upper end of the pole piece of the magnet p, has a slit in it at s in which is
pivotted an armature of steel n² 81 free to move in a horizontal direction between'
the poles of cc-This by induction from 8, which is a south pole will exhibit at
its free end s¹ a south magnetic polarity and so will be indifferently attracted by c
or c¹ but preferentially by the one to which it lies nearest In this case it is
adjusted nearest to c for reasons which will be hereafter explained.
-
Should however by any means the connection at 6+ 6- be reversed the upper
end of p
I would become north the free end of n¹ s' would be also north the free
ends of the cores c c¹ would by induction become south and the action of the
instrument would remain as before.
d' d' e i and i¹ are metallic cups containing mercury for making the necessary
connection, though it may be convenient in some cases to make them of metallic
surfaces or of flexible or other wire d is in connection with b+. i is connected to c.
21 to cand e to b - Their method of working will be explained later on.
These with the other parts of the instrument are represented diagramatically in
Fig. II for the purpose of tracing the current through its various paths when the
№ to c.
instrument is in use.
-
The terminals b + b are for the accumulator and those marked m. + m - are
for the generator. 8¹ represents the free end of the armature n' s¹ having attached
to it two soft iron shoes f. f¹ which are capable of being moved and adjusted so as
to bring s¹ more or less into the magnetic field of c or c¹ which represent the cores
of the horse shoe electro magnét as in Fig. I.
In Fig. III Q is a cover for the magnets (which may be of any suitable form)
and upon which are fixed two supports r. r. for an insulating spindle working in
the bearings thereof rigidly attached to this spindle are the metal arms t. t and the
projection w which fits into a recess in the armature a¹ so that the movement of
the armature causes the spindle with its arms t¹ to rock about its axis u u
u¹ u¹ & v. are metal plungers attached to the arms t t and which dip into the
cups ddii & e which are sunk into the base board o. o. The arms or
plungers u u are given a slight preponderance in weight over u u¹ The cup i
is so filled with mercury that the contact with u' is never broken. Contact at d is
broken when the arm t. is fully depressed towards i.
-
dande are so filled with mercury that when u and u are level they make
contact in both cups only breaking with either of them when the arm t¹is is fully
depressed in either direction.
Tracing the current and explaining its various effects I proceed as follows.
Referring to Fig. II and first taking the current from the accumulators and
following the complete line; the + and of the accumulator being connected

page_text: -
to b + and b
respectively There will be a current through m. c. the coil of p
which will have the effect of polarizing p which will by induction give to the
various parts of the instrument their requisite polarity.
There will also be a current through the cup d the arm t and cup i to one end of
one of the differential coils at c through c to b c should now be north and
attracting & which is south while c¹ is south and repelling it The cups being now
connected as at first.
11
On connecting the generator to its proper terminals a current will flow following
the single dotted line from m + to c¹ through c! and c to d¹ by the arm t to ¹ then
by the double dotted lines through the thick coil which is also wound in the same
direction as the last one viz: so as to make the polarities of c and d opposite to
that of the first differential coil passing through c¹ and c by the thick coil the
circuit is completed at m - As soon as the potential of the generator becomes
sufficiently high to change the polarities of c and o¹ the armature in its passage
towards will move the arms t. t lifting the plungers u. u out of d d and
establishing contact at e Both the fine coils are now cut out The polarizing
current through m. c. the magnet coil of p remaining intact and the generator
current following the double dotted lines will flow from m + to b + through the
accumulator to b to e through and the thick coil of c¹ and c to m As this
coil is wound so that c¹ shall be N the armature will be held over towards o² so
long as power sufficient is maintained in c¹ but the armature s¹ is so adjusted that
it is at all times nearer to c than c¹ consequently on any falling off of the current
through the thick coil the cores will have a tendency to revert to their original
polarized condition as induced by p and c will have an attractive effect on 81
which attraction will be somewhat assisted by the extra weight of u. u. and should
the current fall too low for safe charging the contact at e will be broken and ď ď¹
reestablished leaving the instrument free to reconnect the charging circuit as soon
as the potential is bigh enough for it to safely do so.
-
-
Supposing for an instant that the generator were wrongly connected the current
from it would flow from m - through the thick coil of co to i through and the
fine coil of c c¹ to m + this current being in the same direction as that from the
accumulators the pole c would be more strongly "N". and c¹ more "S" con-
sequently the armature would be held tighter over to c and should the attendant
through ignorance or wilfulness move over the lever arms t t they would imme-
diately on their release revert to their original position.
Again if both the leads of the generator and accumulator were reversed the
magnetic effect in each case being reversed, the instrument would still act with the
same certainty and precision.
Fig. IV is a section taken through the line x-x of Figs. I and III in which
letters of reference correspond with those marked similarly on the other Figs. It
shows also in rather more detail ff the soft iron shoes of s¹ the armature and
their method of adjustment also the manner and adjustment of the sliding weight
on the beam t which beam can be graduated in parts representing the number of
amperes of current which flowing through the thick coil from c¹ to c would suffice
to hold the armature over in the direction of c¹ when the weight is adjusted on any
one lines.
If desired p Fig. I may be a permanent magnet in which the magnet coil m c
will be unnecessary but particular care will have to be observed that the con-
nections of the ginerator and accumulator are correctly made to their respective
terminals as designated.
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 :-
1st. In an apparatus for regulating and controlling electric currents the com-
bination of the various parts acting electrically and magnetically as set forth in the i

page_text: well known and generally accepted magnetic and electrical laws and as explained
in and by the foregoing specification and its accompanying drawings.
2nd. The adaptation of the aforesaid laws and their combination in whole or in
part or the modification in shape or form position or size of any of the parts of the
apparatus as shewn in this specification as may by experience be found necessary
or advisable and the use of such modification in any position or for any purpose
consistent with the original purpose for which the apparatus is designed viz:
regulating and controlling electric currents always providing that the principle of
the invention remains substantially the same.
3rd. The Improved apparatus for regulating and controlling electric currents as
herein before described and set forth.