An Improvement in Electric Meters.
Year: 1890

page_text: Date of Application, 11th Sept., 1890
Complete Specification Left, 7th July, 1891-Accepted, 5th Sept., 1891
PROVISIONAL SPECIFICATION.
Communicated from abroad by Messrs. SIEMENS & HALSKE, of Markgrafen-
strasse, Berlin, in the German Empire, Electrical Engineers.]
An Improvement in Electric Meters.
We, SIEMENS BROTHERS AND CO. LIMITED of 12 Queen Annes Gate,
Westminster in the County of Middlesex, Electrical Engineers do hereby declare
the nature of this invention to be as follows:-
In the Specification No. 11419 of 1889 is described an electric meter in which a
pointer connected to a rotatable solenoid within a solenoid coil through which the
current to be measured passes, is moved to various positions according to the
strength of the current, and a curved armed caused to oscillate at certain intervals
by clockwork or by an electromagnetic relay and arrested by the pointer at different
parts of its stroke according to the position of the pointer, by means of a pawl and
ratchet gives a greater or less amount of motion to a counter, which is thus made to
sum up the successive measurements corresponding with the successive positions of
the pointer. The instrument described in the said Specification is subject to a
defect, inasmuch as the indication and measurement can be vitiated by bringing a
magnet externally into the neighbourhood of the rotatable solenoid and so influencing
it as to cause the pointer to take false positions.
The object of the present invention is to remove this objection, which is effected
by employing, instead of a single rotatable solenoid, several of these of alternating
polarity fixed on one axis so that a magnet brought into their neighbourhood,
attracting half and repelling half of them, has no effect on the position of the pointer
which is fixed on the common axis of the solenoids.
This alteration in the number of solenoids involves certain alterations in the con-
struction of the instrument, but not in the principle of its action which remains the
The clockwork
same as set forth in the previous Specification above referred to.
or its equivalent gives rotation to a crank pin which works in the slot of a lever,
causing this lever to make periodic oscillations.
To this lever is connected by a spring the curved arm which carries a spring
In front of the curved arm
pawl engaged with the ratchet wheel of the counter.
is the pointer, the position of which is determined by the multiple rotatable solenoids
on the common axis of which the pointer is fixed.
As the slotted lever makes one part of its oscillation, it urges the curved arm
towards the pointer by which the arm is stopped, the spring however allowing the
lever to complete its stroke.
As the lever makes its back stroke, it moves the curved arm back through the
distance through which it had been moved until stopped by the pointer, and the
pawl of the arm in this movement gives proportional motion to the counter.
Dated this 11th day of September 1890.
ABEL & IMRAY,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
An Improvement in Electric Meters.
We, SIEMENS BROTHERS AND CO. LIMITED of 12 Queen Annes Gate,
Westminster, in the County of Middlesex, Electrical Engineers, do hereby declare
the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement :-
In the Specification No. 11,419 of 1889 is described an electric meter in which a
pointer connected to a rotatable solenoid within a solenoid coil through which the
current to be measured passes, is moved to various positions according to the
strength of the current, and a curved arm caused to oscillate at certain intervals by
clockwork or by an electromagnet relay and arrested by the pointer at different
parts of its stroke, according to the position of the pointer, by means of a pawl and
ratchet gives a greater or less amount of motion to a counter which is thus made to
sum up the successive measurements corresponding with the successive positions of
the pointer. The instrument described in the said Specification is subject to a
defect, inasmuch as the indication and measurement can be vitiated by bringing a
magnet externally into the neighbourhood of the rotatable solenoid and so influencing
it as to cause the pointer to take false positions.
The object of the present invention is to remove this objection, which is effected
by employing, instead of a single rotatable solenoid, several of these of alternating
polarity fixed on one axis so that a magnet brought into their neighbourhood,
attracting half and repelling half of them, has no effect on the position of the
pointer which is fixed on the common axis of the solenoids.
This alteration in the number of solenoids involves certain alterations in the
construction of the instrument, but not in the principle of its action, which remains
the same as set forth in the previous Specification above referred to. The clock-
work or its equivalent gives rotation to a crank pin which works in the slot of a
lever, causing this lever to make periodic oscillations.
To this lever is connected by a spring the curved arm which carries a spring
pawl engaged with the ratchet wheel of the counter. In front of the curved arm is
the pointer, the position of which is determined by the multiple rotatable solenoids
on the common axis of which the pointer is fixed.
As the slotted lever makes one part of its oscillation, it urges the curved arm
towards the pointer by which the arm is stopped, the spring yielding to allow the
lever to complete its stroke.
As the lever makes its back stroke, it moves the curved arm back through the
distance through which it had been moved until stopped by the pointer, and the
pawl of the arm in this movement gives proportional motion to the counter.
The construction of the meter operating as above described is shewn by the accom-
panying drawings.
Fig. 1 is a plan, Fig. 2 is a side view partly in section of the meter and Fig. 3 is
a front view partly in section of the compound solenoids.
Four pairs of solenoid bobbins B are fixed on a vertical axis A which is free to
oscillate, when these bobbins which are excited by a fraction of the current to be
measured are deflected, in opposition to an adjustable spring C, by the influence of
the current passing through the successive pairs of bars D which act as a compound
solenoid. These pairs of bars D are electrically connected to each other by metallic
bosses E at one end of each pair and are insulated from each other by non-metallic
bosses F of non-conducting material at the other end of each pair, these bosses
alternating at the opposite ends so that an electric current entering at one end of
the uppermost pair has to take a zig-zag course, as indicated by the arrows in
Fig. 3, to the opposite end of the lowest pair of bars. Owing to this course of the
current below each pair of bobbins B in a direction opposite to its course above the
same pair, and to the connections of the coils of these bobbins so as to give the two

page_text: of each pair opposite polarity, and each single bobbin opposite polarity to that of
the bobbins immediately above and below it, whenever an electric current passes
through the bars D and bobbins B, the latter are more or less deflected according
to the strength of the current, moving a pointer G which is attached to the axis A
more or less in opposition to the spring C. Also, owing to the opposite polarities
of the several pairs of bobbins B, they are not effected by the neighbourhood of any
magnet, the attractions and repulsions on the several pairs balancing each other.
The registering part of the apparatus is as follows. Clockwork such as is
described in the previous Specification No. 11,419 of 1889, accommodated in the
space H, gives rotation to a crank pin I which is engaged in the slot in one arm J
of a lever, the other arm of which J¹ is bent upwards. Free on the same axis with
the lever JJ' is another lever one arm K of which is curved and the other arm
carries a spring pawl K engaging with a finely toothed ratchet wheel L. This
ratchet wheel carries a pinion gearing with the first wheel of a counter M which has
suitable indices and dials for recording the number of revolutions and parts of a
revolution of the wheel L. To the bent up arm Jis attached one end of a spring p
the other end of which is fixed to a boss of the lever K K', and from J' extends a
wing piece P towards the arm K'.
The operation of the apparatus is as follows. As the crank pin I revolves in
the direction of the arrow it causes the arm J' to move towards the right straining
the spring p and thus moving the arm K until it is stopped by meeting the end
of the pointer G which may be more or less deflected from its neutral position
according to the strength of current acting on the bobbins B. The arm J¹ goes on
moving to the right until the crank pin I has made half a revolution, but, the
arm K being stopped against G, the farther movement of J¹ only strains the
spring p. As the crank pin I continues to revolve, the arm J returns towards
the left until its wing piece P coming to bear against the arm K' moves it with it
and thus, when the crank pin has completed its revolution, the arm K is brought
back over the same distance as it had moved forward. During this backward move-
ment its pawl k moves the ratchet wheel L which works the counter, and the indices
of the counter are thus moved proportionally to the stroke which the arm K had
made in advancing to meet the pointer G. The curve of K is so shaped that the
distance which it has to move in order to meet the end of G in any position to
which G is deflected, is proportional to the electrical energy which causes the
deflection; and thus the counter registers the summation of the successive amounts
of energy measured at each revolution of the crank I, that is to say at the suc-
cessive intervals of time determined by the clockwork which drives the crank.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In an electric meter in which the position of a pointer due to the deflection of
bobbins mounted on an axis within a solenoid coil determines the stroke of a pawl
lever working a counter, the construction and connections of the solenoid and
bobbins in such manner that the electric current takes in the solenoid a zigzag
course below and above successive pairs of the bobbins, which are alternated in
polarity, those of each pair having polarity opposite to one another, and each
bobbin having polarity opposite to that of the bobbins immediately above and
below it, so that the instrument is not influenced by any external magnetic force,
substantially as described.
2. An electric meter constructed and operating, substantially as herein described
and illustrated.
Dated this eth 1
Ր T..1001
ABEL & IMRAY,
Agents for the Applicants.