Recording Currents of Electricity.
Year: 1887

page_text: Date of Application, 25th Mar., 1887
Complete Left, 25th Jan., 1888
Complete Accepted, 24th Mar., 1888
Recording Currents of Electricity.
I, PAUL BEDFORD ELWELL of Commercial Road Wolverhampton in the County of
Stafford Electrical Engineer, do hereby declare the nature of this invention to be as
follows:
This Invention relates to apparatus for measuring indicating and recording currents
of electricity, and it has for its object to effect the combination in one apparatus of
instruments for indicating the e.m.f.; for indicating the quantity or ampères, and
for registering or recording the total quantity during any desired period.
These Improvements consist in the combination in one apparatus of a voltmeter, an
ammeter, and an electric meter, and in the construction and arrangement of the
various parts or constituents of the combination. The apparatus consists of a high
resistance solenoid motor, for indicating the e.m.f., a low resistance solenoid current
indicator or ammeter, and of appliances for registering and recording the total current,
these appliances being actuated and controlled by the combined operation of the motor
and of the ammeter.
The high resistance solenoid is in a shunt between the lead and return mains.
Coincident or parallel with the axis of the solenoid is mounted a spindle, which carries
upon it within the solenoid a wheel or an equivalent carrier, upon which is fixed an
iron bar or bundle of iron wires parallel with the axis of the solenoid, or in some cases
one or more additional bars or bundles may be carried by or suspended from, but not
fixed to the spindle, but only in such a manner that they cannot come into actual
contact with each other, or with the bar fixed to the spindle. The spindle and the
carrier or carriers should be constructed of a non-magnetic material, and the spindle

page_text: has further fixed upon it a brass or other non-magnetic disc outside the solenoid.
Within the solenoid, close to the coils, there is fixed an iron bar curved plate or
equivalent packet or arrangement of iron wires so disposed that on the rotation of the
bar or bars or bundles of wire, it or they may just clear the fixed bar, plate or wires.
The fixed bar plate or wires occupy such a position that the swinging bar or bars may
when at rest be adjacent thereto; the weight of the bar or bars always brings them to
rest at the bottom, or the same result may be attained by mounting the spindle
eccentrically, and this will give a greater attractive force on one side of the solenoid
than on the other. A platinum or other suitable contact or pair of contacts is attached
to the fixed bar or plate or other suitable fixed part of the apparatus, and to the
rotating bar fixed upon the carrier so that the circuit through the solenoid may be
closed when the fixed bar and the moving bar fixed on the spindle are at their point
or are of nearest approach, and for some distance beyond in the direction of
rotation.
When the main circuit is closed, a current of electricity traverses the coils of the
solenoid and the iron bars plates or packets of iron wire therein become similarly
magnetised and mutually repellant. If one bar only is used the impulse thus given
will carry it over the centre when the force of gravity will be added, bringing the bar
into position for a second impulse, the circuit being broken during the are of approach.
If one bar is fixed upon the spindle, and other bars are suspended therefrom, these
bars by their repellant action will assist the bar fixed to the spindle over the top
centre. The speed of the rotating spindle is controlled by the e.m.f. of the current
and this speed may therefore be employed to indicate directly or indirectly the e.m.f.
of the current. This may be done by a finger attached to the spindle, by a speed
indicator, or by other like and suitable means. There may be attached to the spindle
or be driven thereby a "fly" or pair of wings, a balance wheel, a pendulum or a
light governor, to keep time or to prevent sudden variations of speed with
varying e.m.f.
The disc upon the spindle by its rotation therewith supplies the
motion required for the meter hereinafter described.
The low resistance solenoid is wound with a few turns of thick wire or cable and
is inserted in the main circuit so that the whole of the current to be measured passes
through it. Within the solenoid two or more bars of iron or bundles of iron wires
are suspended from or carried by rigid non-magnetic carriers mounted upon central
axes or spindles, one or more of which must be hollow if the spindles are to be con-
centric, or one of the bars or bundles may be carried from the spindle and the other
or others from carriers hearing or swinging upon the same spindle. Upon one side
of the interior of the solenoid is fixed a bar of iron, or bundle of iron wires similar
to that fixed within the high resistance solenoid. A pointer or index finger may
be attached to one or to each of the suspended bars or bundles of wire to indicate
on a dial the quantity of current passing, and the bars or bundles must be so
mounted or suspended that they cannot come into actual contact with each other
or with the fixed bar or bundle. The suspended bars or bundles are so arranged
that their motion may be resisted or controlled as desired by springs or by gravity,
or by their combined influence. On passing a current through the coils of the
solenoid the bars or bundles will be similarly magnetised and become mutually
repellant; the movable bars or bundles will consequently move through an arc the
length of which is determined by the quantity of current and by the force
counteracting the motion of the bars. It follows then that by loading the bars or
bundles with weights or with lighter or stronger counteracting springs, one bar or
bundle may be made to indicate ampères, another tens of ampères, and others other
quantities as may be desired.
By any suitable connecting device or gearing, such as a cylindrical rack and
pinion the angular motion of the axis of one of the suspended arms may be caused
to traverse a small friction pulley radially upon the face of the disc of the high
resistance solenoid. The friction pulley may have a flexible centre obtained by con-
necting the rim to the boss by means of indiarubber or of springs, so that it may
alter its position upon the disc more readily. Upon the axis of the friction pulley

page_text: is mounted a worm pulley or wheel which operates a suitable counting or recording
mechanism or device. It will be evident that the number of revolutions of the
counting or recording apparatus in a given time will be governed by the speed of
the disc which corresponds to the e.m.f. and by the position of the friction pulley
on the disc which is controlled by the quantity of current, and that therefore the
meter or recording apparatus will or may be caused to give a record of the value of
the current.
The apparatus hereinbefore described may be employed for continuous or alternate
currents.
Dated this 22nd day of March A D 1887

page_text: CUM LEID
!!
A New or Improved Apparatus for Measuring, Indicating, and
Recording Currents of Electricity.
I, PAUL BEDFORD ELWELL of Commercial Road Wolverhampton in the County
of Stafford Electrical 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:-
This invention relates to apparatus for measuring indicating and recording
currents of Electricity and it has for its object to effect the combination in one
apparatus, of instruments for indicating the e.m.f.; for indicating the quantity
or ampères, and for registering or recording the total quantity during any desired
period.
These Improvements consist in the combination in one apparatus of a voltmeter
an ammeter and an Electric meter and in the construction and arrangement of
the various parts or constituents of the combination.
The apparatus consists of a high resistance solenoid motor, for indicating the e.m.f.,
a low resistance solenoid current indicator or ammeter, and of appliances for registering
and recording the total current; these appliances being actuated and controlled by
the combined operation of the motor and of the ammeter. The diagrams on the
annexed sheet of Drawings will enable this Invention to be more readily understood
and carried into effect. Figs. 1 and 3 represent the arrangement diagrammatically
in elevation, Fig. 2 in plan.
The high resistance solenoid A is in a shunt between the lead and return
mains M B. Coincident or parallel with the axis of the solenoid is mounted a spindle
which carries upon it, within the solenoid, a wheel or an equivalent carrier B upon
which is fixed an iron plate, bar tube, or bundle of iron wires C, parallel with the axis
of the solenoid, or in some cases one or more additional bars or bundles may be carried
by or suspended from, but not fixed to the spindle, but only in such a manner that
they cannot come into actual contact with each other or with the bar fixed to the
spindle. In the diagram two iron bars or bundles of iron wire C T are shown. Cis
the bar which is fixed to the spindle. T is a bar which is merely suspended from the
spindle. These bars are so mounted that they may move without coming into contact
with each other. S is a non-magnetic stop which will permit the passage of C and
prevent the passage of T. The spindle and the carrier or carriers should be constructed
of a non-magnetic material and the spindle has further fixed upon it a brass or other
non-magnetic disc D outside the solenoid. Within the solenoid, close to the coils
there is fixed an iron bar curved plate or equivalent packet or arrangement of iron
wires so disposed that on the rotation of the bar or bundle of wire C, it may just
occupies such a
clear the fixed bar, plate or wires E. The fixed bar plate or wires
position that the Bar T may when at rest, be adjacent thereto and the bar a little in
advance. The weight of the bar or bars always brings it or them to rest at the bottom.

page_text: Attraction as well as repulsion may be obtained and utilized by mounting the spindle
excentrically. The relative positions of the bars when at rest may be secured by
counterweights. A platinum or other suitable contact or pair of contacts F is attached.
to the fixed bar or plate or other suitable fixed part of the apparatus and to the
rotating bar fixed upon the carrier so that the circuit through the solenoid may be
closed when the bar is in the positions indicated by the diagram, and for some
distance beyond in the direction of rotation.
When the main circuit is closed with a battery or a dynamo in motion, a current of
electricity traverses the coils of the solenoid and the iron bars plates or packets of iron
wire therein become similarly magnetised and mutually repellant. If one bar only is
used the impulse thus given may carry it over the centre when the force of gravity
will bring the bar into position for a second impulse, the circuit being broken during
the are of approach. When the two bars C. T. are employed and the circuit is closed
when they are in the positions indicated, C being in advance of T and both being
similarly repelled by E, both move in the direction shewn by the arrows until T is
arrested by the stop S. C is now repelled by T until it has nearly reached a vertical
position when the circuit is opened and T falls backwards while C continues its revolu-
tion and both again occupy the positions shewn by the diagram and the cycle is
repeated. The arrangement is thus a simple form of motor having a speed proportional
to the c.m.f. The commutator for opening and closing the circuit is preferably a
platinum faced cam and a platinum tipped spring as indicated at F.
The speed of the rotating spindle is controlled by the e.m.f. of the current and this
speed may therefore be employed to indicate directly or indirectly the c.m.f. of the
current. This may be done by a finger attached to the spindle, by a speed indicator
or by other like and suitable means. There may be attached to the spindle or be
driven thereby a "fly" or pair of wings (or, in case a constant speed is required to
measure quantity regardless of the e.m.f., a balance wheel, a pendulum or a light
governor,) to keep time or to prevent sudden variations of speed with varying e.m.f.
The disc upon the spindle by its rotation therewith supplies the motion required for
the meter herein after described.
The low resistance solenoid G is wound with a few turns of thick wire or cable and
is inserted in the main circuit so that the whole of the current to be measured passes
through it. Within the solenoid two or more bars of iron or bundles of iron
wires H H are suspended from or carried by rigid non-magnetic carriers mounted
upon central axes or spindles one K or more of which must be hollow if the spindles
are to be concentric, or one of the bars or bundles may be carried from the spindle
and the other or others from carriers bearing or swinging upon the same spindle.
Upon one side of the interior of the solenoid is fixed a bar of iron or bundle of iron
wires L similar to that fixed within the high resistance solenoid. A pointer or index
finger may he attached to one or to each of the suspended bars or bundles of wire to
indicate on a dial the quantity of current passing and the bars or bundles must be so
mounted or suspended that they cannot come into magnetic contact with each other
or with the fixed bar or bundle. To prevent this contact contiguous faces of the bars
may be plated with brass. The suspended bars or bundles H H₁ are arranged so
that their motion may be resisted or controlled as desired by springs or by gravity or
by their combined influence. The bars H H may be restored to their normal position
by means of the adjustable counterweights NN or by an equivalent arrangement.
On passing a current through the coils of the solenoid all the bars or bundles will
be similarly magnetised and become mutually repellant, the movable bars or
bundles H H will consequently move through an are the length of which is
determined by the quantity of current and by the force counteracting the motion
of the bars. It follows then that by loading the bars or bundles with weights N N
or with lighter or stronger counteracting springs one bar or bundle may be made
to indicate ampères another tens of ampères and others other quantities as may
be desired.
By any suitable connecting device or gearing such as a cylindrical rack and a
pinion on the spindle of the ammeter the angular motion of the axis of one of the

page_text: suspended arms may be caused to traverse a small friction pulley radially upon the
face of the disc D of the high resistance solenoid. The friction pulley may have
a flexible centre obtained by connecting the rim to the boss by means of india-
rubber or of springs so that it may alter its position upon the disc more readily.
Upon the axis of the friction pulley is mounted a worm pulley or wheel which 5
operates a suitable counting or recording mechanism or device. It will be evident
that the number of revolutions of the counting or recording apparatus in a given
time will be governed by the speed of the disc which corresponds to the e.m.f.
and by the position of the friction pulley on the disc which position is controlled by
the quantity of current through the operation of the bar H or H' and that there- 1
fore the meter or recording apparatus will or may be caused to give a record of the
value of the current.
A convenient arrangement for operating the recording mechanism is indicated
in Fig. 3 and in plan in Fig. 2. U is a silk cord passing round and secured to the
spindle in the solenoid G. This cord is attached at its opposite end to a spiral
spring which keeps it in tension. V is a light metallic tube through which the silk
cord U passes or to which it is secured so that motion communicated to the cord is
partaken by the tube. The friction pulley P is mounted upon the tube in such a
position that it is at the centre of the disc D when no current is passing in the
circuit. When current is passing the bar in G is displaced through a greater or
less angle and moves the spindle in G through a similar angle. Consequently the
cord and therefore the pulley P is correspondingly moved. The greater the current
in G the more nearly it approaches the circumference of D and the more rapidly it
is rotated. It will be evident then that the number of turns made by P in a given
time will be proportional to C × E. The motion of P may be transmitted to the
counting or other mechanism by known incans such as the silk cords and
pulleys Q.
The apparatus bereinbefore described may be employed for continuous or alternating
currents.
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) In an Electric meter, the combination and arrangement of a high resistance
solenoid having one fixed magnetic bar, one or more rotating magnetic bars and a
rotating disc, with a low resistance solenoid having one fixed magnetic bar and one or
more rotating magnetic bars, a rack and pinion or an equivalent device for trans-
forming rotary into reciprocal motion, and a friction pulley operated by the rotary
dise; substantially as and for the purpose hereinbefore described.
(2) In an Electric meter; the construction and arrangement of a high resistance
solenoid motor for originating constant motion or motion proportional to the c.m.f.
of the current, substantially as hereinbefore described with reference to the appended
diagrams.
(3) In an Electric meter the construction and arrangement of a low resistance
solenoid device for originating motion proportional to the current, substantially as
herein before described with reference to the appended diagrams.
(4) In an Electric meter; a disc rotated at a speed proportional to the c.m.f., in
combination with a friction pulley capable of being moved radially upon the disc to a
position nearer to or further from the circumference of the disc proportional to the
strength of current; substantially as hereinbefore described.