AN IMPROVED APPARATUS FOR MEASURING ELECTRICAL PROVISIONAL SPECIFICATION
Year: 1882

page_text: LETTERS PATENT to Theophilus Varley, of Marsh Street, Walthamstow, in
the County of Essex, Electrician and Engineer, and Henry Bickerton
Greenwood, of Monmouth Road in the County of Middlesex, Gentleman,
for an invention of
" AN IMPROVED APPARATUS FOR MEASURING ELECTRICAL
PROVISIONAL SPECIFICATION left by the said Theophilus Varley & Henry
Bickerton Greenwood at the Office of the Commissioners of Patents on the
12th May 1882.
THEOPHILUS VARLEY, of Marsh Street, Walthamstow in the County of Essex,
Electrician and Engineer, and HENRY BICKERTON GREENWOOD, of Monmouth
Road, in the County of Middlesex Gentleman "AN IMPROVED APPARATUS FOR
MEASURING ELECTRICAL CURRENTS
ور
The object of this Invention is to provide means for measuring, that is to say
indicating and registering correctly the amount or quantity of electricity supplied
from any source for lighting or other purposes so that any person using electricity
may know the amount which has been supplied to him.
In a meter or apparatus which shall correctly measure and record the quantity
of electricity supplied or used in any period of time it is essential, first, that the
speed of the apparatus shall be so governed that its rate of rotation will not be
altered or interfered with by friction or surplus power. Second, that the electric
current passing the said meter shall be continuous or un-intermittent.
According to our invention we obviate or prevent the detrimental influence of
friction, and surplus power by the use of a train of wheels or clockwork governed
or controlled by a lever escapement and balance or other means for ensuring
regularity of motion. This train of wheels is to be driven or actuated by an
electric current.
The said clockwork actuates a disc or plate which rotates with a uniform speed;
geared with this disc or plate, by friction or otherwise, is a small wheel which is
the first wheel of the indicating gear and which may or may not be provided with
an indicating hand. This first wheel is arranged to gear with the face of the said
Price Gd1

page_text: disc or plate and is capable of moving farther from, or nearer to, the centre of the
same according to the current; that is to say, when no current is passing, this
wheel will be at the centre of the said disc and when a current is passing it will
be moved away from the centre thereof. For instance when say one unit of
current is passing, the said wheel will be moved by the force of the same to a point
on the disc say about inch, more or less, from the centre of the said disc and
when two units are passing it will be moved to about inch, more or less, from
the centre of the said disc or to a point on the disc where its motion is exactly
double that of the first named point thereon and the speed of the said first wheel
will be increased in proportion to its distance from the centre. Thus an increase
or diminution of the current will increase or diminish the distance of the first
wheel from the centre of the disc or plate so as to ensure a correct register of the
consumption of the electric fluid or power.
The said first wheel may be made to approach or recede from the centre of the
said plate or disc according to the strength of the continuous current of electricity,
by means of helices or electro-magnets acting on a wheel in which a current passes
from the centre to the periphery or vice versa, or by a wire, or helices, acting
against a helice or electro or permanent magnet or magnets, or bars or pieces of
soft iron, during the passage of an electric current.
The said first wheel may be made, by means of levers, cams, springs, weights, or
cranks, to move in such manner that when a current of one unit of electricity is
passing through the electrical part of the meter it will indicate one and when two
or more units are passing it will indicate two or more, and although, the force
moving the said first wheel may increase in the ratio of the square or other
electrical progression by the adjustment of the aforesaid cams, cranks, levers,
springs or weights, the said first wheel will be moved the proper distance from the
centre of the rotating disc or plate and caused to rotate at an increasing or
decreasing rate of speed in direct proportion to the strength of the electric current
passing through the meter, and will thus indicate accurately the amount of
electricity supplied to the consumer.
The first wheel of the indicating mechanism is geared to wheels similar to those
usually employed in gas meters for a like purpose which wheels are arranged to
register 10, 100, 1000, 10,000, or more units as may be required.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Theophilus Varley & Henry Bickerton Greenwood in the Great
Seal Patent Office on the 11th November 1882.
THEOPHILUS VARLEY, of Marsh Street, Walthamstow, in the County of Essex,
Electrician and Engineer, and HENRY BICKERTON GREENWOOD, of Monmouth
Road in the County of Middlesex, Gentleman. "AN IMPROVED APPARATUS FOR
MEASURING ELECTRICAL CURRENTS
"
The object of our invention is to provide means for measuring, that is to say,
indicating and registering correctly the amount or quantity of electricity supplied
from any source for lighting or other purposes, so that any person using electricity
may ascertain the amount which has been supplied to him.
In order that a meter or apparatus shall correctly indicate and register the
quantity of electricity supplied or used in any period of time, it is essential first,
that the speed of the indicating mechanism shall vary with, and according to, the
current passing through the circuit in which the apparatus is included and
consequently that such speed shall not be sensibly affected or interfered with by
friction; also that the electric current shall be continuous or unintermittent.
According to our said invention we obviate or prevent the detrimental influence
of friction by constructing the apparatus in the manner hereinafter described, that
is to say; We provide a disc fixed to a spindle carried in suitable bearings and
arranged to be rotated by an electro-motor, a spring, a weight, or other suitable
means, its speed being maintained at a uniform rate by a train of wheels and an
escapement, or other device for ensuring regularity of motion. In combination
with this disc we employ a roller or wheel carried in a pivotted arm or frame, the
said roller or wheel, and the frame, being arranged to be oscillated by the varying
attractive force of an electro-magnet or solenoid included in the circuit through
which passes a part or the whole of the electric current to be measured, or by
means of any suitable device capable of electro-magnetic action. The shaft of the
said roller or wheel is connected with any suitable indicating and registering
mechanism, which is preferably carried by the said pivotted arm or frame.
provide a roller, a cam, or other suitable device in connection with the armature of
the electro-magnet or solenoid, for transmitting the movements of the said
armature to the frame.
We
In the accompanying drawing we have illustrated two forms of apparatus whereby
our said invention may be carried into practice.
Figure 1 represents a front elevation of one form of our improved apparatus.
Figure 2, represents another form or modification of the same.
a represents a base-plate or stand of suitable construction, upon which the said
apparatus is mounted; 6 is an electro-motor, c is the disc fixed upon the spindle d
which forms an extension of, or is connected to, the axis of the said motor. The
spindle & has fixed on it the toothed wheel d³ forming part of a train of wheels the
motion of which is controlled by the action of an ordinary or any suitable
escapement, so that the speed of the said spindle and disc is kept at a uniform rate
although the strength of the current actuating the motor may be in excess of that
required. The disc c is arranged to operate the indicating mechanism in the
following manner, that is to say;-We arrange, in combination with the said disc,
the roller e to the axis of which is fixed the pointer f and the gear-wheel f¹ of the
indicating mechanism. The roller e is supported and fitted to turn freely in
bearings in the frame g which is pivotted at g¹ to the lever h, this lever being

page_text: e
jointed or pivotted upon a pin or stud i fixed in a bracket on the base plate a.
The roller è is held in frictional contact with the disc c by means of the springs j
attached at one end to the frame g and at the other end to any suitable stationary
part of the apparatus. These springs can, if desired, be made adjustable to regulate
the friction between the disc and roller. The frame g carries at its upper end
the indicating and registering mechanism and has an extension at its lower end to
which is attached one end of a cord or chain k, whose other end is attached to a
roller or to a cam or excentric l. This cam or excentrix Z is carried by a small
shaft m turning in bearings in the standard or bracket n and having fixed to it a
piece o which forms the armature of the electro-magnet p. This electro-magnet p
is included in the circuit of the current to be regulated.
The operation of this apparatus may be understood by the aid of the following
explanation, that is to say-It is obvious that the disc and the roller c are in
frictional contact; when no electric current is passing the said roller is in such a
position that a point thereof bears against the centre of the said disc and it is
obvious that although the disc continues to revolve it then imparts no motion to
the roller or drum e; but when an electric current is passing through the circuit
the said electro-magnet or solenoid attracts the armature towards its pole p*. As
this armature moves in a circular path to which the axis of the magnet is
tangential, the said armature does not move into contact with the pole and its rate
of movement diminishes as it approaches the same; and this rate of movement, by
the proper proportioning of the excentric or cam, the levers and the springs, is
caused to impart to the roller a movement or adjustment accurately in proportion
to the variations in the current, that is to say, the cam 7 fixed on the axis m of the
armature o, acting through the cord or chain k, turns the frame g upon its pivot g¹
and thereby moves the roller e upon the disc c one unit of distance nearer the
periphery of the said dise for each unit of current and the speed of the roller e and
consequently of the indicating mechanism is thus made to vary with and in
proportion to the current passing through the circuit.
According to the modification of our invention illustrated in Figure 2 the
working surface of the disc c is concave and is arranged to gear with a small
wheel e carried by the arbor of the first wheel f¹ of the indicating mechanism.
This wheel e¹ is carried in a pivotted arm or frame g and is arranged to gear with
the concave face of the said disc in such a manner that it can be moved farther
from or nearer to the centre of the same, in a similar manner to that above
described, according to the variations of the current.
In this case, however, the amount of friction between the wheel e and the surface
of the disc might be sufficient to affect the action of the apparatus, as the wheel
is moved over the said surface, and to avoid this friction we prefer to adopt the
arrangement in which the roller is used as above described, this roller may have
either a conoidal or a cylindrical surface pressing against the disc which is made
flat or convex accordingly, that is to say, in some cases we make the surface of the
roller cylindrical and the face of the disc convex, and in other cases we make the
surface of the roller conoidal and the face of the disc flat, or we make the roller
conoidal and the disc convex, so that by tilting the roller it is brought into contact
with the face of the disc further from or nearer to the centre, thereby increasing or
diminishing the motion of the indicating mechanism according to the strength of
the controlling current.
Having thus fully described our said Invention and the manner of performing
the same, we wish it understood that we claim, for the measurement of electrical
currents :-
First. The improved apparatus wherein the speed of the indicating mechanism is
caused to vary with, and in proportion to, the current passing through the circuit,
by means of a roller or wheel arranged to be brought into contact with different
parts of the surface of a disc rotating at a uniform speed as above set forth.
Second. In the said apparatus, the employment of an electro-magnet, a solenoid,

page_text: or other suitable device for bringing the roller or wheel into contact with
different parts of the surface of the disc, substantially as, and for the purpose, set
forth.
In witness whereof we the said Theophilus Varley and Henry Bickerton
Greenwood have hereunto set our hands and seals this Eleventh day of
November in the year of our Lord One thousand eight hundred and
sight tran
THEOPHILUS VARLEY (L.S.)
HENRY B. GREENWOOD (LS.)