Improvements in Electricity Meters.
Year: 1892

page_text: Date of Application, 6th July, 1892
Complete Specification Left, 26th Nov., 1892-Accepted, 28th Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Electricity Meters.
We JOSEPH EDMONDSON, of 36 Sunbridge Road, Bradford, in the County
of York, Electrical Engineer, and JOSEPH OULTON, of Providence Mills, Harris
Street, Bradford in the County aforesaid Clock Maker, do hereby declare the
nature of this invention to be as follows:-
This invention firstly provides, a means by which sparking may be the more
effectually lessened or prevented wherever an electric circuit is repeatedly closed
and opened; as for instance in the driving of a pendulum, or chronometric balance
by means of an arm actuated by gravity or a spring such for instance as the gravity
arms in the well known "Becketts gravity escapement," but operated by electro-
magnetic force.
Our improvement consists in combining a resistance with a condenser and the
electric circuit of an electro magnet.
Secondly. In electricity meters in which electrically driven pendulums, or
electrically driven chronometric balances as aforesaid are used, we provide for
stopping the said pendulums or balances when the supply current is intermitted and
for starting them when the current is again switched on. As long as the current is
supplied to the meter it causes an electro magnet to hold a catch out of the way of
a hook, or it ivalent, attached to the pendulum or balance; but as soon as
the current is intermitted the magnetism ceases, the catch is released, and engaging
with the hook, holds the pendulum or balance away from its neutral position or
"dead point." When the current is again switched on, the magnet withdraws the
catch and in so doing, gives a slight impulse to the pendulum or balance,, which
immediately resumes its vibrations.
The third part of our invention relates to electricity meters in which two
pendulums or two chronometric balances are used; said pendulums beating
synchronously when no current is passing into consumption, the amount of variation
from such synchronism caused by the current when going into consumption being
the basis of measurement. In order the more effectually to insure the said
synchronism we attach the two pendulums to a bar which is common to both
of them and which is itself held by a more or less elastic support.
In the case of two chronometric balances, we suspend these from more or less
elastic supports which are connected together by a rod or bar by which the
vibrations are more or less communicated from the one to the other.
WALTER
BRIERLEY,
Penny Bank Chambers, Waterhouse Street, Halifax,
Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Electricity Meters.
We JOSEPH EDMONDSON of 36 Sunbridge Road, Bradford, in the County
of York, Electrical Engineer, and JOSEPH OULTON of Providence Mills, Harris
Street, Bradford aforesaid, Clock Maker, 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 improvements in electricity meters in which the
vibrations of a chronometric balance or balances, pendulum, or pendulums in

page_text: combination with magnets, or solenoids are made to record the amount of electric
current or energy passing into consumption, and consists :-
Firstly. In combining a resistance with a condenser and the electric circuit
of the electro-magnet, so as to lessen or prevent sparking at the point where the
pendulum, or balance opens, or closes the said circuit.
Secondly. To improvements in apparatus for stopping the said pendulums.or
balances when the electric current is intermitted, and also for restarting the said
pendulums, or balances when the current is again switched on.
Thirdly. To improvements in electricity meters in which two pendulums or
chronometric balances are employed, such pendulums or balances being required to
beat synchronously when no current is passing into consumption. In order the more
effectually to insure such synchronism we attach the two pendulums to a bar which
is common to both of them, and which is itself held by a more or less elastic support.
In the case of two chronometric balances we suspend these from more or less
elastic supports which are connected together by a rod or bar by which the
vibrations are more or less communicated from the one to the other.
Such being the nature and object of our said invention, the following is a
complete description of same, reference being made to the accompanying drawings
in which similar letters, or figures of reference point to the same, or similar parts
throughout.
Fig. 1. is a front elevation of the pendulum form of our improved electrical meter,.
or apparatus for measuring and indicating the amount of electric current or energy
passing into consumption, such apparatus being electrically connected with a train of
wheels, and dials such as illustrated by Figs. 4. 5 and 6.
Fig. 2 is a detail of part of Fig. 1. drawn to an enlarged scale in order to shew
its construction more clearly.
Fig. 2 is a similar view to Fig. 2 but shewing the action of the magnet and
weight reversed.
Fig. 3. is an end sectional elevation on line A. B of Fig. 1.
Fig. 4. is a front elevation of the indicating dials.
Fig. 5. is a plan view of Fig. 4 shewing the train of wheels for operating the
hands of the dials.
Fig. 6. is a detail of part of the indicating mechanism drawn detached in order
to shew its construction more clearly.
Fig. 7. is a front elevation of a part of Fig. 1. drawn detached and with the
pendulum rod removed in order more clearly to illustrate part of the invention.
Fig. 8. is an end view of Fig. 7 the pendulum rod being in position.
Fig. 9 is a plan view of Figs. 7 and 8 but shewing a resistance coil connected to
and combined with the apparatus and the condenser.
Fig. 10 is a front elevation of the apparatus as constructed when chronometric
balances are employed in lieu of the pendulums.
Fig. 11 is an end view of a part of Fig. 10.
Fig. 12 is a plan view of part of Fig. 10 the position of the chronometric balance
being indicated by the dotted lines.
Fig. 12 is a detail of Fig. 12 drawn to an enlarged scale in order to shew its
construction more clearly.
Referring first to meters in which pendulums are employed, and to Figs. 12
and 3 of the accompanying drawings at 1. 1. are two pendulums (whereof one is an
ordinary pendulum which may be conveniently regulated by a screw 33 as shewn,
and the other is a pendulum influenced by the current to be measured in any
convenient manner. We prefer the method shewn in the drawing, which consists of a
fixed main coil 58. together with the volt or high resistance coil on the pendulum,
as hereinafter described and marked 65.) which being made to vibrate the required
motion is maintained by gravity arms 2. 2, said arms 2. 2. are mounted on axes
free to move in the carrying frames or brackets 3. 3 (see Figs. 7. 8. and 9.).
Mounted loosely in the said brackets 3. 3 and below each of the arms 2. 2. is an
armature 4 one end of which is near to the electro magnet 5 and the other end

page_text: is provided with a counterbalance weight 6. On each pendulum rod 7 is a short
cranked finger 8 (see Fig. 2.) at the outer end of which is an adjusting screw 9
and also a small blade spring 10 fixed at one end by a screw or otherwise on the
said cranked finger 8. The free end of the spring 10 rests on the adjusting screw 9.
On the upper side of the spring 10 is a small projection, or a piece of platinum 11
which, as the pendulum vibrates, comes in contact with a similar projection 12 on
the gravity arm 2. A screw 13 (Figs. 7. 8 and 9) limits the amount of movement
of the armature 4.
The action is as follows:-In a state of rest, or in the normal position the
counterbalance weight 6 holds the armature 4 in contact with the screw 13 and
away from the electro magnet 5. the gravity arm resting on the top side of the
armature 4. As the pendulum vibrates and moves to nearly the limit of its arc in
one direction the projection or platinum 11 on the cranked finger 8 will come in
contact with the projection or platinum 12 on the gravity arm 2. At the moment
of contact, and while the pendulum moves through its supplementary arc (the circuit
being closed as hereinafter described when referring to the different coils and their
connections) the armature 4 is attracted to the electro magnet 5. When the
pendulum moves in a reverse direction the gravity arm 2 falls with it until the arm
rests upon the armature 4. The circuit is then opened by the part 11 moving
away from the part 12 and the armature leaves the magnet and lifts the gravity arm
to its original position.
It will be seen that the gravity arm falls through a longer are than that through
which it is raised by the vibrations of the pendulum, the difference being the height
to which the gravity arm is raised by the armature 4. The repeated fall of the
impulse arm 2. through this short distance is sufficient to maintain the vibrations of
the pendulum. The impulse arm may be actuated by a spring instead of by gravity.
It will be evident that the action of the magnet and weight 6 may be reversed
as shewn in Fig. 2. In this case the gravity arm 2 is mounted in bushes which
insulate it from the frame 3 its arbor being electrically connected to the bar 30 by
a light flexible connection.
When the gravity arm 2 rests on the top of the weight 6 the electric circuit of
the magnet 5 is completed, the armature 4 is consequently drawn down, and the
gravity arm 2 is lifted along with the weight 6. When the pendulum moves in the
direction of the arrow and lifts the gravity arm 2 by means of the screw 9
the circuit is broken at 11. 12. the magnet 5 releases the armature 4, and the
weight 6 falls as far as permitted by the stop 13. When the pendulum moves in
the reverse direction the gravity arm 2 falls with it until the arm rests again
on the weight 6, completes the circuit and the magnet 5 again lifts the weight 6
and gravity arm 2 to the first named position.
In order to lessen or prevent sparking at the points of contact 11. 12 whenever
the electric circuit is opened or closed, we combine an ordinary condenser such as 14
and a resistance coil such as 17 with the electro-magnet 5, a wire 15 from the
frame 3 being connected with one side of the condenser, and a wire 16 connects
the opposite side of the condenser 14 to the resistance 17 (see Figs. 1 and 9.)
placed between the condenser 14 and the circuit of the electro-magnet, as shewn.
The improved apparatus for stopping the pendulums 1. 1, when the current is
intermitted, and for restarting the said pendulums when the current is switched on,
consists of an electro magnet 18 near the bottom of which is hinged an armature 19
the outer ends of which are cranked as at 20, and the cranked ends 20. 20 pass
underneath the two arms 21. 21 which latter rest on the cranked ends 20. 20. The
arms 21. 21 are at their inner ends hinged, or free to move on fulcrum pius 22. 22
and their outer ends carry the pins 23. 23. A hook 24. is fixed on the rod 7 of each
of the pendulums 1. 1 in such a position as to engage with the pins 23. 23 when
these are in their lowest position. When current is passing through the circuit of
the electro magnet 18 the said magnet holds up the armature 19 which then
supports the arms 21. 21. in a position too high for the hooks 24. 24 to engage
with the pins 23. 23. But when the current is switched off the armature 19 falls

page_text: and allows the armature 21. 21 to fall by gravity to their lowest position. When
this is so (as the pendulums 1. 1. vibrate towards one another) the inclined edges 25
of the hooks 24 will come in contact with, and move underneath the pins 23. 23
until the latter fall into the catches 26. 26 of such hooks. The pendulums 1. 1. are
thus stopped and will be held stationary at an elevation above their dead point.
As soon as the electric current again switched on, the electro-magnet 18 will
draw to it the armature 19 and the cranked ends 20. 20 will raise on their centres
the arms 21. 21 and pins 23. 23 and as the latter move up the inclined faces 26. 26
with a sharp movement the pendulums 1. 1. receive a slight impulse towards
each other, the hooks 24 are released from the pins 23 and the pendulums resume
their vibrations.
The lifting action of the magnet 18 is made more certain by a larger current
temporarily passing through the circuit of the magnet by way of the hooks 24. 24
pins 23. 23 and arms 21. 21 as hereinafter described.
In order that the synchronism of the two pendulums 1. 1. may be effectually
maintained when no current is passing into consumption, we attach the two
pendulums 1. 1. by the usual suspension springs 27. 27 to a bar 28 common to both
pendulums, and this bar 28 is itself supported by springs 29. 29. (or other elastic
support or supports) which are attached to a bar 30 secured to the box or casing of
the meter. Passing through a slot or hole in the bar 28 is a screwed pin 31 fixed
in the bar 30 and nuts 32 are placed on each side of the bar 28 so that the latter
can be held rigid, or nearly so, by causing the nuts 32 to nip it between them.
This bar 28 being thus made rigid or nearly so the pendulums 1. 1 are made to
beat synchronously by the regulating weight 33 which is screwed up or down on
the pendulum rod as required. The bar 28 is then released from the grip of the
nuts 32. 32. and the synchronism is maintained. The screwed pin 31 and the
nuts 32. 32 may be dispensed with, but in this case the primary adjustment of
the pendulums for synchronism will not be so accurate.
When in lieu of the pendulums 1. 1 we employ chronometric balances 1. 1. (see
Figs. 10 and 12.) the said balances 1. 1 being made to vibrate, their motion is
maintained by the impulse arms 2. 2 which are mounted on axes 35 free to move in
the carrying frames or brackets 3. 3. On the axis 35 is a vibrating spring 34
(preferably similar to the balance spring of a watch). Mounted loosely in the
brackets 3. 3. is an armature 4 one end of which is near to the electro magnet 5
but held (when no current is passing round such magnet) against the adjusting
screw 13 by the spring 6. It is shewn in the drawing Fig. 12. as attracted by the
magnet, and away from the said adjusting screw 13. On each balance 1 is a pin 11
which, as the balance vibrates, comes in contact with the end 12 of the impulse
arm 2. The action is as follows:-In a state of rest, or in the normal position,
the spring 6 holds the armature 4 against the adjusting screw 13 and away from
the electro magnet 5. The impulse arm 2 then rests against the armature 4 being
retained there by the force of the spring 34.
As the balance vibrates and moves
to nearly the limit of its arc in the direction of the arrow the pin 11 will come in
contact with the end 12 of the impulse arm 2. The balance continues its motion
through its supplementary arc (the circuit being closed as hereinafter described
when referring to the coils and their connections) the armature 4 is attracted to
and held by the electro magnet 5. When the balance moves in the reverse
direction the impulse arm 2 is made by the spring 34 to follow it until it comes in
contact with the armature 4, the pin 11 then leaves it behind, the circuit is broken,
and the armature 4 being released the spring 6 brings it back to the stop 13 and
carries the impulse arm 2 with it. It will be seen that the impulse arm 2 moves
through a shorter arc when carried by the balance in the direction of the arrow
than when it returns with it, the difference being the distance between the position
of the armature 4 when it is against the magnet, and its position when against the
adjusting screw 13. This difference gives the required impulse to the balance.
The apparatus employed for stopping and restarting the balances 1. 1 is similar
to that described with reference to Figs. 1 and 3 excepting that the pin 23 is fixed

page_text: UHIC
to and at about the centre of gyration of the radius of the balance 1, and
springs 36 (see Fig. 12.) are employed to keep the arms 21. 21 in contact with the
cranked ends of the armature 19. The arms 21. 21 terminate in the hooks 24. 24.
As long as the current is passing around the magnet 18 the armature is held by it
and the arms 21. 21 are held with their hooks 24. 24. out of reach of the pin 23
but when the current is switched off the armature 19 is released and the hooks 24. 24
are by the springs 36 brought within range of the pins 23 which they catch and so
hold the balances in a position away from their neutral or dead point, until the
books are withdrawn by the renewed action of the current.
In order that the synchronism of the balances 1. 1 may effectually be main-
tained when no current is passing into consumption we attach the two balances 1. 1
by the usual torsion suspension springs 27. 27 (Figs. 10 and 11.) which are supported
by the much stronger springs 29. 29 or other somewhat elastic support or supports
attached to a bar 30 secured to the box or casing of the meter. The elastic
supports 29. 29. are connected to one another by the bar 28 the supports 29. 29.
being bent or having a crank formed on them, and these cranks 37 are received in
the recesses 38 formed one at each end of the bar 28 and held by means of
the small springs 39. 39. their ends resting in the notches 40. 40 of the
recesses 38. 38.
The action and result of suspending the balances 1. 1 as described is similar to
that hereinbefore described in reference to Figs. 1 and 3. The index which records
the amount of electric current or energy passing into consumption, to which we
make no separate claim, consists of the dials, and hands (see Figs. 4 and 5) the
hands being actuated by the train of wheels (see Fig. 5) such train of wheels
being operated and operating as follows: The electric circuits of the two electro-
magnets 41. 41 are connected in series with the electric circuits of the magnets
which actuate the impulse arms (one to each) and near to each magnet 41 is an
axis 42 (seen most clearly in Fig. 6) on which is fixed the armature 43 and also the
lever 44, the upper end of which has two cross arms 45, 45 in which are pins 46, 46
carrying the blade springs 47. 47 which engage with the teeth of a ratchet or
catch wheel 48 carried on an arbor 49 which passes through a slot 50 in the lever 44.
On the arbor 49 is a pinion 51 gearing with and driving the wheel 52 of the
differential motion 53 and on the arbor 49" is the pinion 51ª gearing with and
driving the wheel 52 of the differential motion. When current passes around the
electro magnets 41. 41 (in consequence of the circuits being closed at the contacts 11
and 12, by the vibration of the respective pendulums or balances) the armatures 43, 43
are attracted to such magnets 41. 41 consequently the axes 42, 42 are turned part
of a revolution and the levers 44, 44 are moved in the direction indicated by the
arrows in Fig. 6 the ends of the upper blade springs 47. 47 come in contact with
the teeth of the ratchet or catch wheels 48. 48 and the latter are turned a space of
half a tooth. When the circuit is again opened the spiral springs 54. 54 move the
levers 44, 44 in a reverse direction to that indicated by the arrows in Fig. 6 and
the lower blade springs 47. 47 now move the ratchet or catch wheels 48. 48 a space
of half a tooth in the same direction as before.
This to and fro movement of the levers is repeated so often as the circuit is
opened and closed by the pendulums or balances consequently the pinion 51 rotates
and drives the wheel 52 in a reverse direction to that in which the pinion 51° drives
the wheel 52°. So long as the speed of these wheel 52. 52ª is the same the wheel 55
will remain stationary.
When the speed of the wheel 52 varies from the speed of the wheel 52" in con-
sequence of the deviation from synchronism of the pendulums or balances caused
by current going into consumption the wheel 55 will rotate and set in motion the
train of wheels or clockwork which drives the hands or indices. The stop pins 56. 56
on the levers 44. 44 prevent the ratchet or catch wheels 48. 48 moving more than
the distance or space of half a tooth at one time or for one vibration of the
levers 44. 44.
The electro magnets in this invention may be either with or without iron cores

page_text: and their armatures may be either of iron or of a coil or coils placed in a shunt
-circuit and with or without iron cores.
Although we have hère described the application of the first and second parts
of this invention to electricity meters constructed as described in the Specification
lodged subsequently to our application for a Patent dated 13th February 1892
No. 2831 yet it will be readily understood that they are applicable to meters in
which only a single pendulum or balance is used to which construction each of the
above named parts of our invention equally applies.
We will now describe how the different parts of the apparatus are connected
together, and indicate the flow of the electric current through the meter.
At 57 (see Fig. 1) is the main supply wire along which the current passes
around the fixed main coil 58 to the lamps. The wire 57 is connected by shunt
wire 59 with the bar 30 through which a current for actuating the movements and
index passes down the springs 29. 29 and pendulum rods 7. 7 and (when contact
is made between the parts 11. 12) along the gravity arm 2 to the frame 3 which
is connected (as shewn in Fig. 9) by the wire 15 to the resistance 17 thence
by wire 15 to one side of the condenser 14 the opposite side of the condenser
being connected by the wire 16 to the bar 30 or the reverse as shewn in Fig. 1.
We prefer inductive resistances as shewn in the drawings and one of them may
be placed on each side of the condenser 14 if desired or thought necessary.
The circuit is continued from the frame 3 by wire 60 round the magnets 5. 5
and by wire 61 to the index. Another current passes along the pendulum rod
to the fork 63 thence by wire 64 to correcting and volt coils, 65 which are
upon and form part of the pendulum or balance and whose functions are here-
after described. From the correcting coil 65 the current passes up the pendulum
rod 7 by the wire 66 away to the main wire for supplying the lamps. A wire 67
from the volt coil 65 also passes along the pendulum rod to the frame 3° of the
electro magnet 18 and the current flows by wire 68 to said electro magnet and
thence by wire 69 to the supply terminal. The wires 66. 67 may be carried inside
the pendulum rod 7 the latter being made hollow for this purpose. When the
hooks 24. 24 are engaged with the pins 23: 23 of the arms 21. 21 a short circuit is
formed between the pendulum rod 7 through such hooks 24 pins 23 arms 21 and
frame 3" to the electro-magnet 18 thence to the supply terminal. The volt coil 65
being thus temporarily cut out the magnet 18 is much more powerful, and when
the current is switched on the armature 19 is strongly attracted and moves sharply
to the magnet 18.
The connections are similar when torsion balances are employed excepting that
wires 70. 70 are employed dipping into the mercury cups 71. 71 by way of which
the current passes as indicated in Fig. 10.
It will be seen that instead of the current to the magnet 18 being passed through
the volt coil, when the pendulums are vibrating it might equally well be passed
instead thereof through a separate coil of similar resistance coupled between the
frame 3 and the main wire 57, or further instead of the contact between the
hooks 24 and the pins 23 cutting out the said separate resistance coil or the volt
coil, the said contact might close the circuit of a second coil placed on the
core of the magnet 18 by which the magnetism would be temporarily increased as
required.
A very small current is continually passing through the shunt circuit which
includes the volt coil, the magnetic effect of which is in proportion to the electro
motive force of the current. When current is passing through the fixed main coil
to the lamps, the magnetic force of the main coil and of the volt coil combined,
accelerate or retard the vibrations of the pendulum such acceleration or retardation
being registered on the dials and being except as hereinafter described in proportion
to the watts passing into consumption.
The force required to produce the vibrations of a pendulum is in proportion to
the square of the number of vibrations. If therefore a = the normal number of
vibrations and the number to be added by the current the force required to
==

page_text: produce a will be a² and to produce a + b will be a² + 2 a b + b³, the difference.
(2ab+b) being the force to be exerted by the current under measurement.
With the volt coil alone the force actually exerted would be in the ratio 2 a b + b².
only.
Upon each volt coil therefore there is wound the "correcting coil" carrying a
very small proportion of the current passing into consumption. If correctly
calibrated this small current brings the ratio up to 2 a b + b and makes the
readings proportional throughout any range.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
Firstly. Electricity meters constructed substantially as herein described and
substantially as illustrated by the annexed drawings.
Secondly. In an electricity meter in which a pendulum or chronometric balance
actuated by electricity is used the lessening or prevention of sparking at the point.
at which a circuit is opened or closed, by combining a resistance with a condenser
and the said pendulum or balance and the points of contact as herein described and
illustrated by Figs. 1 and 9 of the annexed drawings.
Thirdly. In the case of electrically driven pendulums or chronometric balances.
the combination therewith of an electro magnet, or electro magnets with hooks or
catches which are prevented by the said magnet or magnets from engaging when
the current is on, but which being released when the current is switched off, trap.
or catch the pendulums or balances and hold them at a distance from their dead
points until the current is again switched on as such mechanism is herein described
and illustrated by annexed drawings and for purpose herein set forth.
Fourthly. In a Watt meter the combination with pendulums or chronometric
balances and an electro magnet whose circuit is in series with the volt coil, of
hooks or catches which are prevented by the said magnet from engaging when the
current is on, but which, being released when the current is switched off, trap or
catch the pendulums or balances and hold them at a distance from their dead
points until the current is again switched on as such mechanism is herein described
and illustrated by Figs. 1. 3. 10 and 12 of the annexed drawings and for the
purpose herein set forth.
Fifthly. In electricity meters in which hooks or catches combined with an electro
magnet are employed for trapping or stopping, and restarting pendulums or chrono-
metric balances the use of such hooks or catches to convey a current which shall
temporarily increase the energy of the said magnet for the purpose of attracting
the armature as herein set forth and as illustrated by Figs. 1. 3. 10 and 12 of the
annexed drawings.
Sixthly. In the case of two pendulums or chronometric balances intended to
vibrate synchronously, the combination with them of a bar, rod or other connection,
by which the vibrations of the one may slightly influence those of the other and
thereby the more effectually maintain the synchronism as herein described and
illustrated by Figs. 1. 3. 10 and 11 of the annexed drawings.
Dated this 25th day of November 1892.
JOSEPH EDMONDSON,
JOSEPH OULTON,
By their Agent, Walter Brierley,
Penny Bank Chambers, Waterhouse Street, Halifax.