Improvements in Electric Meters.
Year: 1891

page_text: Date of Application, 19th June, 1891
Complete Specification Left. 19th Apr., 1892-Accepted, 28th May, 1892
PROVISIONAL SPECIFICATION.
Improvements in Electric Meters.
1, PARIS EUGENE SINGER Esq. Gentleman, 6 Victoria Road, Kensington W.
lo hereby declare the nature of this invention to be as follows:-
The object of my invention is to produce an instrument for measuring and
recording the quantity of electricity which flows through conductors by means of
the property possessed by air (or other gas) of expanding when heated.
In carrying out my invention I connect two bulbs or vessels of equal volume and
preferably identical shape by a tube containing mercury. Through either of these
bulbs a coil of naked wire passes. The current flowing through this wire which is
insulated from the walls of the bulb, heats it, and the enclosed air causing the latter
to drive the mercury into the other bulb. When the mercury attains a particular
level in the bulbs, the fact of a certain quantity of electricity having passed, is
declared and the mercury on attaining this level, is made to close a derived (or an
independent) circuit which excites an electro-magnet and this in turn operates a
step instrument" consisting of a rack or pall in connection with a train of clock
wheels by means of which the fact of a definite quantity of electricity (which I
shall henceforward call the unit) having passed is permanently recorded.
But the action of the electro-magnet on the " step
instrument" docs more than
this registration. It also breaks the circuit containing the coiled naked wire in the
bulb and switches on the current to be measured, to a similar naked coiled wire in
a perfectly similar bulb, when a similar action goes on and a record of another
"unit" having passed is made by the clock train.
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It is to be noted that each excitation of the electro-magnet causes its own coils
to be taken out of that circuit which has just been closed by the moving mercury
(after the manner of a cut out) and puts them (its coils) into the circuit to be
closed by the mercury of the next pair of bulbs to be called into action.
The number of these pairs of bulbs is large enough to allow the air in the first
which is called into use, to cool down to its original state, before it is called a second
time into requisition. Any change of temperature of the apartinent in which the
apparatus is placed occuring meantime does not effect the instrument, since both
bulbs of each pair are of equal volume and identical shape. Neither can change
of pressure vitiate it since cach pair of bulbs with their connecting mercury tube is
air tight.
When I wish to merely measure the current passing through a conductor, one
pair of bulbs with coil only is necessary. The level reached by the mercury in a
given time, measures the current strength, because it measures the heat produced;
and in order to fix a definite time it is arranged that on connecting the conductor
carrying the current to be measured to the instrument, a sand glass (or similar
time-measurer) is automatically brought into play, and it is further arranged that
when the sand has run out, its weight (or other property) breaks the circuit carrying
the current being measured. The position of the mercury in the tube at that
moment gives the magnitude of the current.
1001

page_text: COMPLETE SPECIFICATION.
Improvements in Electric Meters.
| PARIS EUGENE SINGER, 6 Victoria Road, Kensington, in the County of
Middlesex, Gentleman, 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 my invention is to produce an instrument for measuring and
recording the quantity of electricity flowing through a conductor, utilizing the
property possessed by air (or other gas) of expanding when heated.
In carrying out my invention, I connect two closed vessels of equal capacity, and
preferably of the same shape, by a tube containing mercury. In one of these
vessels, I insert a coil of naked wire connected with the source of supply of
electricity. The current flowing through this wire heats it and the air confined in
the enclosing vessel, causing the air, by reason of its expansion, to drive the
mercury upwards to the other vessel. When the mercury reaches a given level,
the fact of a certain quantity of electricity having passed, is indicated; and the
mercury, on attaining this level, is made to close a derived (or an independent)
circuit, which, by exciting an electro-magnet, may operate a counting apparatus,
and, at the same time, break the circuit, and switch on the current to a similar
measuring instrument, when the like action is repeated on the counting apparatus.
Any given number of these measuring instruments may be provided, for being
brought in succession into circuit, the object being to allow the heated air of each
instrument to cool down to its original state before it is called a second time into
requisition.
In the accompanying drawings, Fig. 1. shews, in front elevation, two measuring
instruments connecting, through a switch, with the line conveying the current to be
measured, and also with a counting apparatus which marks the units of current
measured alternately by the two instruments. One of these instruments (No. 1) is
shewn in section, the better to illustrate the construction, which is identical in both,
and No. 2 in side elevation.
In both these instruments, A is a closed metal vessel containing a coil of naked
wire a, one end of which is connected to an insulated binding screw a', to which is
attached one of the "leads "a for the main current; the other lead a³ connects,
through the binding screw a and the walls of the vessel A, with the other end of
the coil a.
B is a closed vessel of equal capacity with the vessel A, and made preferably of
glass. B¹ is a straight tubular extension of the vessel B, and connecting, through
a U-shaped tube C, with the vessel A. This tube C is filled with mercury, which
remains quiescent therein during the normal state of the apparatus,
Fitted to the vessel B, is a cover of insulating material, in which are fitted two
binding screws bb, carrying pendent wires which reach to the bottom of the vessel,
and attached to the binding screws are wires 62 & 3 of a derived circuit connected
with the switch D, which is in mechanical connection with the counting
apparatus E.
Supposing, now, a current to be passed through the coil a of the measuring
instrument No. 1, the temperature of the coil will be raised, and the confined air in
the vessel A will be caused to expand, and drive forward the mercury in the
tube C, thereby causing it to rise up the tube B', until it reaches the pendent wires
in the vessel B. At the moment this occurs, a unit of current will have passed
through the coil, the proportions of the apparatus having been adjusted to that end.
Action will now take place in the counting apparatus, for the purpose of marking,
on the unit dial, that a unit of current has passed. This action is attained by
rocking the switch d, which for this purpose is provided with a pair of electro-
magnets d¹ & d² (see the plan view Fig. 2), that underlie the rocking bar d of the
switch D. These electro-magnets serve alternately, as they are energized, to

page_text: depress the ends of the rocking bar d, and draw them into one or other of the
mercury cups d' d', situate beneath them, and connected with the lead a² through
one or other of the coils a in the two measuring instruments. The middle
mercury cup d' connects with the lead a³.
The coils of the magnets d', d² connect, at one end, with the lead a²; the other
ends of the coils connect, the one, d', with the binding screw of the measuring
instrument No. 1, and the other magnet coil with the corresponding binding screw
of No. 2 instrument,
The apparatus, as shewn in the drawing, indicates that the instrument No. 2 has
just been cut out of circuit by the rocking of the bar d, and that the current to be
measured is flowing through the coil of No. 1 instrument. As the temperature
increases in the vessel A, the column of mercury will rise, and close the derived
circuit by touching the pendent wires in the vessel B. The result of this rise of
the mercury, which indicates, as before mentioned, the passage of a unit of electric
current, will be to energize the electro magnet d', and draw down the switch bar d
to the dotted position, breaking, at the same moment, the circuit completed by the
switch bar in the drawn position.
I have said that the switch is connected mechanically with the counting
apparatus. This is effected by pivotting, to an arm of the switch lever, a rod e,
which connects with a rocking arm working on a fixed fulcrum at or near its
centre, and carrying, at opposite sides of the centre, pawls ee², which take into a
ratchet wheel e³ of the counting apparatus.
It will now be understood that at every dip of the switch bar d, caused by the
rise, to its full height, of the mercury in one or the other of the measuring
instruments, the ratchet wheel e will be driven forward one tooth, and the count
of one unit of current passed will be indicated on the unit dial.
Simultaneously with the marking of this unit, the supply of the current to No. 1
instrument will be cut off, and the course of the current will be changed back to
No. 2 instrument, leaving the vessel A. of No. 1 to cool down before being brought
again into use. As, however, the time required for cooling may be too short to
secure accurate measurement, I propose to employ a group of these instruments;
which will be thrown into circuit in succession, and will thus allow the time for
cooling to be increased to any extent thought desirable.
The manner of carrying this out will now be explained.
Fig. 3 is a diagram shewing five measuring instruments of the construction
above described, all in connection with the lead wires through a rotating switch F.
This switch consists of a disc of insulating material, mounted on the axle of the
ratchet wheel of the counting apparatus, which wheel is made, say, with twenty
teeth.
The disc fis provided on its face with a series of concentric rings f,BAR
corresponding in number with the measuring instruments contained in the series,
and on the edge of the disc are contact pieces equal in number to the teeth of the
ratchet wheel, and divided equally among the five concentric rings with which they
are respectively in electrical connection. Bearing on the periphery of the disc, is
an elastic electric conductor fe, connected with the lead a². The contact surface
of this electric conductor is of sufficient length to allow of a fresh contact being
made before the other is broken. ƒ ƒ ƒ ƒ**, and *, are elastic electric
conductors bearing upon their respective concentric rings, f, ƒ³, ƒ^, ƒ³,
connected each with the coil a of their respective instruments.
1*
and
It will now be understood that at every axial motion of this disc, caused by the
step by step movement of the ratchet wheel, the course of the current will be
diverted from No. 1 measuring instrument to No. 2; from No. 2 to No. 3, and so
on, until the cycle is completed by the current passing from No. back to No. 1,
and so on in the like order.
The movement of the ratchet wheel is effected by a pawl carried by a T-shaped
tipping lever f, which is attracted by an electro magnet f³ towards the ratchet
wheel & drawn back, when the attraction ceases, to its normal position by a

page_text: spring. This electromagnet is situate in a derived circuit with which all the
instruments are permanently connected as described with reference to Figure 1.
It will now be understood, that each time a unit of current is passed through a
measuring instrument, and the rise of the mercury closes the circuit, the electro-
magnet will be energized, and will cause the lever to rack round the wheel one
tooth, and, through the disc f, switch the current to the next measuring instrument
of the series.
In order to measure simply the quantity of electricity passing through a conductor
in a given time, a single measuring instrument will serve my purpose. From what
has gone before, it will be understood that as the level reached by the mercury
measures the heat produced, it will only be necessary to watch the time-rate of the
rise of the mercury, to ascertain the amount of electricity passing.
To facilitate this object, I employ the apparatus shewn in Figures 4, 5, 6, and 7,
in which a clock-work is provided for breaking and making circuit.
Fig. 4 is a front view of the apparatus; Figure 5 is a plan view; Figure 6 an
elevation of the left hand end; and Figure 7 an elevation of the right hand end of
the apparatus.
Figures 4 are detached views of the rock lever, and the arms ¹² & 12, in
their position of rest. G is a train of wheels actuated by a main spring H, which
drives a fan that regulates the running down of the spring. The arbor of this
spring is fitted with a winch handle for winding it up to a limited degree, the limit
being determined by a stop h
Mounted on the arbor of this spring, are two arms ', ², the use of which will be
presently explained.
In line with the spring arbor, is mounted on a rock shaft I, which carries two
prongs, which dip into separate mercury cups i i. These cups are connected, the
one with the line wire, and the other with the measuring instrument (say No. 1,
Fig. 1).
3 is a horizontal rock lever, one end of which lies in the path of the arm h' of
the spring arbor, when the arbor is at rest; the other end of this rock lever rests
against a bent arm carried by the rock shaft 1.
Supposing, now, the spring H to be wound tip to the extent allowed by the
stop h, and the running down of the clock to require a certain definite time for its
completion, it will be readily understood that this apparatus will provide the
element of time required for rating the rise of the mercury in the measuring
instrument.
The operator having wound up the spring, and having his eyes upon the
measuring instrument, lets go the handle, and allows the clock-work to run down ;
the arm of the spring arbor now strikes the rock lever ³, and passing that lever,
is free to continue its further movement. The tipping of this lever.imparts, through
the arm, a rocking motion to the shaft. I, which depresses the prongs into the
cups, and closes the circuit with the measuring instrument.
The operator, with his eyes still on this instrument, notes the arrest of the clock-
work, representing a given period, and, at the same moment, the height at which
the mercury has attained. The spring, in completing its limited action, brings the
arm of its arbor into contact with the arm of the rock shaft, and striking it,
causes that shaft to lift the prongs out of the mercury cups, and break the circuit,
thus preventing the further rise of the mercury, which is then free to return to its
normal position.
From this explanation it will be understood that it is the height which the
mercury has attained within the limited period assigned for its rise, that gives the
true indication of the quantity of electricity passing through the "leads."
Having now particularly described and ascertained the nature of my said inven-
tion and what manner the same is to be performed, I declare that what I
claim is -
:-
1. The measuring instrument described with reference to Fig. 1 of the drawings

page_text: in which two closed air vessels connected with a mercury tube are employed for
controlling, by their contained air, the movement of the mercury initiated by the
heat of a coiled wire, or its equivalent, contained in one of the vessels, and in
circuit with the conductor carrying the current to be measured.
2. The arrangement of measuring instruments, whether in duplicate or in a group
of three, four, or more, with a counting apparatus as described with reference to
Figs. 1, 2 and 3 of the drawings, wherein, when unit quantity has passed through
the measuring instrument, the instruments are in turn thrown out of circuit, for the
purpose above set forth.
3. The means above described with reference to Figs. 4, 5, 6, and 7, for
ascertaining the quantity of electricity that passes in a given time.
Dated this 19th day of April 1892.
NEWTON & SON,
Agents for the Applicant.