An Improved Form of Integrating Watt or Ampere Hour Meter for Continuous or Alternating Currents.
Year: 1896

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 18 of. the Patents, &c., Act, 1883) as allowed by
the decision of the Comptroller General, of the 24th day of March 1898.
Date of Application, 6th June, 1896
Complete Specification Left, 8th Mar., 1897-Accepted, 10th Apr., 1897
PROVISIONAL SPECIFICATION.
An Improved Form of Integrating Watt or Ampere Hour Meter for
Continuous or Alternating Currents.
We, ALWYN WALTER STAVELEY, ISAAC HARDY PARSONS, and THOMAS
JOHN MURDAY, all of Faraday Works, Braunstone Gate, Leicester, Electrical
Engineers, do hereby declare the nature of this invention to be as follows:-
The apparatus herein described, and shown in the accompanying drawings
consists of three principal parts, viz.:-(1) A timekeeper, in the form of a pendulum
electrically driven. (2) An ammeter or watt-meter indicating on an equally
divided scale, and (3) A decimal dial mechanism-similar to those used in gas and
other meters.
The pendulum A. Fig. 1 is actuated by the electro-magnet B the bobbins of
which are set apart sufficiently to admit of the pendulum bob swinging between:
only one bobbin is shown on the drawing. C is the armature, consisting of a bar
of soft iron swinging over the poles of the electro-magnet B. The pendulum is
suspended preferably on pivots, working in the plate D and bracket E. In Fig. 1
the pendulum rod is shown with the middle portion removed so that the ratchet
wheel F and mechanism therewith connected may be better seen. The contact
springs G. H. are fixed on an insulated block and are adjusted so as to be slightly
apart at the points of contact.
K is a V-shaped brass pendant hanging freely from a stud fixed on the
pendulum rod. When the pendulum is hanging vertical the point of the pendant
engages in the groove shown in the small block on spring G, thus pressing G into
contact with H. Current is then passing through the electro-magnet B and attract
ing the armature on the pendulum. As the pendulum swings over the magnet the
pendant K is drawn off the block on spring G and the current ceases. When
the pendulum swings back the pendant trails over the block on spring G, and on the
next normal return of the pendulum, again catches in the groove and completes
the circuit as before.
If the pendulum swings beyond a certain arc, the pendant is then trailed off
the block on G and does not catch in the groove-consequently the electric circuit
is not completed through the magnet until the swing of the pendulum is reduced
to its normal value. The pendulum is thus self-regulating and is capable of
keeping very accurate time: it is also self starting as it stops always with the
pendant K in the groove on spring G when the current is cut off. The electro-
magnet and contact springs are on a shunt circuit with suitable resistance while
the current to be measured passes through the ammeter coil O.
L is a spring lever fixed to a bracket and has depending from it the catch or
pawl M. This lever rests lightly on a small roller N fixed to the side of the

page_text: pendulum rod. As the pendulum swings this roller works on the inclined face
of L causing an up and down motion of sufficient amplitude to turn, by means of
the pawl M, the wheel F, one tooth at each complete swing of the pendulum.
The shaft of the wheel F, passes through the plate D), and on the opposite end it
carries a crank R, Figs. 2 and 3. This crank gives motion to the lever S which is
pivotted on the shaft of the large ratchet wheel P. Lever S carries a pin U and
ratchet spring or pawl V engaging with wheel P. The pin end of lever S being
heaviest, falls by gravity-consequently, the other end of the lever always lies
against the lower side of the crank pin, and follows it in its motion.
X represents the pointer of an ammeter pivotted at Y, and indicating on the
scale Z the current in amperes. The principal of the apparatus necessitates the
ammeter pointer being locked during part of the time, and Fig. 4 shows in detail
the special form taken by this locking arrangement:-
a is a rod fixed on bracket b, another lighter rod C is pivotted top and bottom
on this rod sufficient space is left between for the free movement of the ammeter
pointer (shown in section at X). A spiral spring e gives a twisting motion to rod c
and thus binds the pointer tightly between it and rod a. A slanting projection fis
so adjusted that when the crank is near its lowest position the lever S is pressing
on it and forcing the rod c slightly around, thus increasing the opening and free-
ing the ammeter pointer. The pointer is thus free once every revolution of the
ratchet wheel to take up its position on the scale corresponding to the amount of
current passing through the ammeter coil.
The reasons for this locking arrangement will now be seen-As the ratchet
wheel F and the crank work round under the impulse of the pendulum the lever S
slowly descends until the pin U rests on the ammeter pointer: it remains in this
position until the crank has performed more or less of its revolution and comes
against the lever again, when it is slowly raised and in its movement carries
round with it the ratchet wheel P. When the crank is at its lowest point, the
pin on lever S must then correspond with the zero point on the ammeter scale.
It thus becomes evident that the distance through which the lever S oscillates
is determined by the distance of the ammeter pointer from zero.
If the ammeter pointer is near the bottom of the scale the lever S will descend
through a large arc and the ratchet wheel P will be moved through a corre-
spondingly large arc, as the lever S returns to the zero of the scale. Should the
pointer only show 1 or 2 amps., the arc described by the lever and wheel will be
correspondingly less.
With a pendulum swinging half seconds and with 30 teeth in wheel F, the
lever S actuates the ratchet wheel P every 30 seconds. The movement of this
wheel is shown on the dial by the centre pointer, and the smaller dials are
geared down from the spindle of this wheel so as to indicate direct the reading
in units.
The apparatus may be applied to measure any quantity of current without any
modification beyond using an ammeter suitable for the current to be measured,
and altering the pitch of the gearing between the centre spindle, and the next
spindle in the train of the dial mechanism.
Dated this 5th day of June 1896.
ALWYN W. STAVELEY.
ISAAC HARDY PARSONS
T. J. MURDAY.

page_text: An Improved Form of Integrating Watt or Ampere Hour Meter for
Continuous or Alternating Currents.
We, ALWYN WALTER STAVELEY, ISAAC HARDY PARSONS, and THOMAS
JOHN MURDAY, all of Faraday Works, Braunstone Gate, Leicester, Electrical
Engineers, 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:-
Our invention relates to an improved electricity meter which we believe will
register the quantity of current consumed more accurately than electricity meters
as heretofore constructed and which will at the same time indicate to a consumer
the quantity of current which is being consumed at any moment, thereby enabling
him to check the consumption of current from time to time.
According to our invention we make use of any ordinary ammeter or watt-meter
and we provide for recording at regular intervals the indications of the said
ammeter and totalling the results on a series of dials.
In carrying out our invention we make use of a motor driven at a substantially
uniform speed by part of the current to be measured such for instance as a pendulum
or balance wheel, and we utilize this motor for rotating an arm or crank co-operating
with a lever (which in our Provisional Specification was referred to as the lever S
but which is hereinafter referred to as the recording lever) which actuates, through
the medium of suitable mechanism, such for instance as ratchet mechanism, the first
wheel of a recording train to a greater or less extent according as the free
end of the said recording lever projects more or less into the path of the said
rotating arm.
In conjunction with the recording lever we arrange what we term a "feeler"
(pin U in Provisional Specification) which, under the action of a spring or of
gravity, normally bears against the hand or pointer of the ammeter to regulate the
position of the free end of the recording lever relatively with the rotating arm
according to the position of the hand of the ammeter.
To prevent the contact of this feeler with the hand of the ammeter from moving
the said hand, we provide a clamping or gripping device which normally holds or
locks the said hand of the ammeter. In connection with the rotating, arm which
operates the recording lever we arrange a cam surface which during the action of
the said rotating arm upon the recording lever (at which time also the feeler is
moved away from the hand of the ammeter) moves the gripping or clamping
device to release the hand of the ammeter and allow it to take up a position
corresponding to any variation which may have taken place in the quantity of
current being consumed whilst the said hand was held by the said clamping or
gripping device.
To enable our invention to be fully understood we will 'describe the same by
reference to the accompanying drawings, in which:-
Figure 1 is a front elevation of our meter; and,
Figure 2 is a section on the line 2-2 Figure 1:
Figure 3 is a rear view, drawn to a larger scale than Figure 1, of some of the
mechanism of our meter; and,
Figure 4 is a section on the line 4-4 Figure 3:
Figure 5 is a view of some of the parts shewn in Figure 1 but in a different
position to illustrate their operation; and,
Figure 6 shews some of the same parts in another position:.
Figure 7 is a section on the line 7-7 Figure 3;
1

page_text: Figure 8 is a diagram illustrating a modification of our invention.
a is the casing of our meter which may be of any suitable construction but which
as shewn in the drawings has corner pillars b, b carrying between them sheets of
glass. c is the coil of an ammeter fixed to a plate d carried upon pillars d', d
fixed to the base, board or plate of the casing, the hand or pointer é of the said
ammeter being arranged to work over a scale e', as shewn in Figures 1 and 3.
fg are the positive and negative circuit wires or cables respectively, the former,.
which includes the coil of the ammeter, being connected to two binding posts h, h¹
which are in communication with the terminals of the ammeter coil through the
conducting strips or plates i, ¹ and the terminal plates j, j to which the terminals
of the ammeter coil are directly connected, as shewn in Figues 1 and 2, so that the
whole of the current to be measured passes through the meter. k, k are lamps
arranged in parallel between the conductors.
I is the motor which as shewn is a pendulum carried by an arbor supported in
the plate d and in a bracket 2 fixed thereto, Figures 1 and 4, and m is the electro-
magnet for operating the said pendulum the said magnet receiving its current from
the terminal plate j through the wire m¹, Figures 1 and 2, and a contact making
and breaking device, the current after passing through the said magnet returning
through the wire m² to the main conductor g. In order to protect the said magnet
from injury owing to the passage of an excessive amount of current through it and
also to limit the quantity of current used for operating the pendulum we arrange
between the said magnet and the conductor a suitable resistance such as the
coil n, Figures 1 and 2.
In order further to economize the quantity of current consumed, the contact
making and breaking device which we employ in connection with the electro-
magnet m is not necessarily operated to close the circuit at each oscillation of the
pendulum but only at such times as the oscillation of the pendulum falls below a
certain arc of movement. A suitable contact device for this purpose is shewn in
Figures 1 and 5, as, however, this contact device forms the subject matter of an
application of later date than this application no claim is made to it in this
application. o, ol are two contact springs in the wire m' which springs are normally
separated, as shewn in Figure 5. Upon the rod of the pendulum is pivoted, so as
to swing very freely, a pendant or trip piece p and on the contact spring o is a
block p notched to receive the end of the said trip piece, as shewn in Figure 1, the
said trip piece and block being so related to each other as regards length and
thickness that when the pendulum is at rest in its vertical position and the end of
the trip piece is upon the block p¹ the contact spring o will be depressed into
contact with the spring o¹.
The length of the block p¹ is such that with a normal arc of oscillation of the
pendulum the trip piece p will pass right over the said block pl without moving
the spring o but that when the swing of the pendulum falls below a certain limit
the said trip piece p will not clear the block, as shewn in Figure 6, so that on the
return swing of the pendulum in the direction of the arrow Figure 6 the said spring
will be pressed down in a manner which will be readily understood by reference to
Figures 1 and 6 whereupon the circuit of the magnet m will be completed and will
impart a fresh impulse to the pendulum.
The number of oscillations which the pendulum makes without a fresh impulse
will be dependent upon the amount of work which the pendulum has to perform
which work will slightly increase in proportion as the amount of current consumed
increases. The notch in the block 7 serves to ensure that when the trip piece is
in contact with the said block it shall not for any reason slide along and off the
same without depressing it. With this arrangement we obtain a pendulum doing
variable work having practically no timekeeping error beyond the usual temperature
error and we can avoid this small inaccuracy by the use of a compensating pendulum.
q is the arm which is rotated by the pendulum, the said arm being mounted on
one end of an arbor q¹ on the other end of which is a ratchet wheel q³ with which

page_text: engages a spring pawl q³, Figures 1 and 4, carried by pivoted arm q. On the
underside of the arm is an inclined cam surface q against which a roller 9°
carried by a pin on the pendulum rod is designed to operate in order to oscillate
the said arm q and so move the pawl to operate the ratchet wheel q³. q' is a
counterweight fixed on the arm to balance the lever so as to reduce the amount.
of energy which the pendulum has to expend in moving the said lever to a minimum.
r is the first wheel of a recording train of wheels and r is the recording lever
hereinbefore referred to, which recording lever at one end carries a series of
pawls,, engaging with teeth on the periphery of the wheel r, two or more pawls
being used in order to subdivide the length of a tooth of the ratchet wheel whereby,
very small movements can be imparted to the said wheel r in a manner which will
be readily understood. 0, are detent pawls engaging with the wheel r. The
other end of the recording lever is designed to be engaged by a pin on the
rotating arm q to move it through a greater or less arc according as the lever r
projects more or less across the circular path of the arm q.
s is the feeler fixed upon the recording lever, the said feeler having a bent ends¹
which normally rests against the hand or pointer e of the ammeter under the weight
of the end of the recording lever carrying the pawls r.
It is to be understood that when the hand or pointer of the ammeter is at the
zero position, as shewn in the drawings, the feeler will retain the recording
lever out of the circular path of the arm q so that as the said arm rotates under
the movement of the pendulum no movement will be imparted to the recording
lever. When, however, the hand e moves more or less over the scale e', the feeler s
by following up the said hand brings the recording lever into the path of the
pin of the rotating arm g so that at each rotation of the said arm g the recording
lever and consequently also the wheel r will be moved a corresponding distance.
It will be obvious that a proper relation must be established between the several
parts in order to obtain proper records, for instance, assume the hand of the
ammeter to be at the first division on the scale which indicates say a current of one
ampere passing and assume also that one rotation of the wheel r corresponds with
a current of one ampere passing for one hour and that the arm q is rotated by
the pendulum to make one revolution per minute, then the recording lever
must be so arranged relatively with the wheel r and with the arm g that if the
wheel has say 120 teeth it will be moved a distance of two teeth at each oscillation
of the lever. If the hand of the ammeter is at the second division of the scale
the movement of the wheel r should be four teeth and if at the tenth division of the
scale twenty teeth.
In practice we find it advantageous to fix in connection with the wheel ra
pointer t, Figure 1, moving over a dial u, as shown in Figure 1, one rotation of the
pointer t around the said dial u under the above assumed conditions corresponding
to a consumption of current of one ampere for one hour. If a current of 10 amperes
at an E.M.F. of 100 volts passing for one hour indicates a Board of Trade unit
then it will be obvious that the pointer t in recording one unit will move ten times
around the dial u. A dial u¹ is advantageously arranged so that one revolution of
its pointer indicates one unit of electricity and other dials u, u, u, may be
arranged in a well known manner for recording tens of units, hundreds of units and
thousands of units.
It will be obvious that with a meter constructed in this manner a consumer can,
knowing the quantity of current which a lamp or lamps should consume, readily
check the consumption.
is the clamping or gripping device which serves to hold the hand e of the
ammeter against movement by the contact of the feeler therewith. This gripping
device comprises a frame adapted to rotate upon its axis between two pivots or
trunnions vi, v, Figure 3, and having two bars 2, 3 (notched as shewn in Figure 4
at 3) between which the hand of the ammeter moves as shewn in Figure 7.
When the said frame is turned to the position shewn in Figure 7 the index or
pointer of the ammeter will be held against movement; when, however, the said

page_text: frame is turned upon its axis to place the bars v2, v3 in a different plane from that
shewn then the hand e of the ammeter is free to move under the action of its
operating coil c. The movement of this frame is effected by the arm which
carries a cam surface which at each rotation of the said arm q acts against a
lever w¹ engaging with an arm a in connection with the said frame. As, as herein-
before stated, the arm 7 makes say one rotation per minute, it will be obvious that
the hand e of the ammeter will be released each minute to allow of the ammeter
adjusting itself. to any variations which may have taken place in the quantity of
current passing during the preceding minute. This release of the hand of the
ammeter takes place at the time when the pin is acting against the lever
whereby the feeler is moved. back to its zero position and so cannot impede the
free movement of the hand e when adjusting itself.
A curved surface r+, is formed in this recording lever r¹ which curved surface ia
concentric with the path of the pin 3 when the said recording lever is in a position
corresponding with the zero position of the index or pointer, whereby the feeler is
retained in its zero position for a definite period of time, to allow the ammeter
hand or pointer time to come to rest, if not of the dead beat type and the clamping
device to close again to hold the ammeter hand in its new position, before the
feeler again comes into contact with it.
In Figure 3 of the drawings we have represented a meter wherein the ammeter
dial is graduated uniformly, that is to say, wherein equal movements of the hand e
correspond with equal variations of current. In this case the axis of the recording
lever is represented as being placed vertically above the axis of the hand e of
the ammeter so that equal movements of the ammeter hand make substantially
equal movements of the feeler and consequently also of the recording lever r. It is
well known, however, that equal movements of the ammeter hand do not always
correspond with equal variations of current, this will be understood by reference to
Figure 8 wherein the lines y, y are lines corresponding with equal variations of
current. In order that in this case the unequal movements of the hand may ensure
equal movements of the feeler and consequently of the lever r¹ the axis of the said
lever is arranged to one side of the vertical line passing through the axis of the
ammeter hand, for instance, to the point z as shewn in Figure 8.
2 is a spring adapted to engage and hold the lower end of the pendulum for
transport purposes, the said spring being disengaged when the meter is in use and
held by a turn-buckle 22.
Although the foregoing description refers to the use of an ammeter it is to be
understood that a Watt meter can be applied with equal advantage.
It is also to be understood that instead of using a pendulum as a time keeping
motor we may use any other motor suitable for the purpose, as for instance, a
balance wheel as hereinbefore indicated.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same.is to be performed, we declare that what
we claim is:-
1. In an electricity meter the combination of a motor driven at a uniform speed
by a part of the current to be measured, an ammeter or Watt meter having a hand
or pointer the position of which varies to correspond with the variations of current
passing through the said ammeter or Watt meter and a lever in connection with
counting or recording mechanism and adapted to extend more or less into the path
of a device upon the electrical motor for periodically operating it, the position of
the said lever relative with its operating device being determined by the hand or
point of the ammeter or Watt meter; substantially as described and illustrated in
the accompanying drawings.
2. In an electricity meter wherein an indicating ammeter or Watt meter is
employed and wherein a feeler is used for ascertaining the position of the hand or
pointer of the said ammeter, a clamping device for holding the said hand or pointer

page_text: of the ammeter against movement by the said feeler the said clamping device being
periodically moved to disengage the said hand or pointer, substantially as, and for
the purpose described, and illustrated in the accompanying drawings.
3. The manufacture and use of the improved electricity meter consisting of the
parts constructed and combined, substantially in the manner herein before described
and illustrated in the accompanying drawing and operating as, and for the purposes,
set forth.
Dated the 8th day of March 1897
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.