Improvements in Electric Meters.
Year: 1892

page_text: Date of Application, 27th June, 1892
Complete Specification Left, 16th Aug., 1892-Accepted, 17th Sept., 1892
PROVISIONAL SPECIFICATION.
Improvements in Electric Meters.
I JOHN WILLIAM JONES of 13 Dornton Road Balham in the County
of Surrey Engineer do hereby declare the nature of this invention to be as
follows:
:-
In electric meters which depend for their action on the difference in rate of two
clocks, one of which clocks is accelerated or retarded by the current to be
measured, a difficulty exists in maintaining synchronism between the two clocks
when no current is flowing. I am aware that this has been partially met by
connecting the pendulums by a loop of flexible cord at the middle of which hangs
a small weight this arrangement however has the disadvantage that a sudden
alteration in the current sometimes stops one of the pendulums, by my invention I
overcome this difficulty by connecting the two pendulums by a fine cord of silk or
other suitable material with or without the weight as above mentioned but to the
centre of this cord or to the weight (if used) 1 attach one end of each of two cords
similar to the first the free ends being attached to two sides of the case or other
suitable supports, thus forming two more loops similar to the first, at or about the
centre of each of these two loops hangs a small weight. By these means I am
enabled to obtain greater accuracy in synchronism without the risk of stopping the
proper action of the meter.
Dated this Twenty-seventh day of June 1802
COMPLETE SPECIFICATION.
Improvements in Electric Meters.
1, JOHN WILLIAM JONES, of 13 Dornton Road, Balham in the County of
Surrey, Engineer, 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 :-
My invention relates to electric meters of the kind or class in which two clocks
are employed one of which is accelerated or retarded when a current flows through
the meter the difference in time of the two clocks being a measure of the energy
which has passed through the meter.
In these meters a difficulty exists in maintaining synchronism between the two
clocks when no current is flowing, the meters are thereby rendered inaccurate. I
am aware that this has been partially overcome by connecting the pendulums of the
two clocks by a loop of flexible cord at the middle of which hangs a small weight,
this arrangement however has the disadvantage that a sudden alteration in the
current frequently stops one of the pendulums.
According to my invention I connect the two pendulums by a fine cord of silk
or other suitable material either with or without the weight above mentioned; to
the centre of this cord or to the weight, if used, I attach one end of each of two
cords similar to the first, the free ends of the said cords being attached to the two
sides of the meter case or to other suitable supports, thus forming two other loops.
At or about the centre of each of these second loops I hang a small weight.
In order that my invention may be more clearly understood I will now proceed
to describe the same with reference to the accompanying drawings, in which:
Figure 1 is a front view of a meter in which the pendulums are connected by
cords according my invention, and

page_text: Figure 2 shews how my invention may be applied to a meter the clocks of which
are controlled by balance wheels, instead of pendulums.
Similar letters of reference denote corresponding parts in both the figures.
Referring now to Figure 1, A. is the meter case, B B₁ are the pendulums of the
clocks. The pendulums B, B1 are first connected by the single string C having a
small weight at or near its middle point C₁ and to the said weight or to the
point C, the ends of the second loops Care connected, the free ends of the same
being joined to the case A as shewn. Small weights C³ are provided at or near
the middle points of the second loops. The weights C³ may be about one gramme
each and I may adjust the weights or the point C¹ until the pendulums are in
synchronism.
In Figure 2 I have shown how my invention can be applied to a meter in which
balance wheels are employed instead of pendulums. In that case the ends of the
first loop C are secured to the arbors or axles of the balance wheels B, B', the
arrangement of the second loops, C² being the same as hereinabove described with
reference to Figure 1.
I prefer that the sag in the loop C should be about 8 inches and it may be
twice the sag in either of the loops C³.
By my invention I obtain greater accuracy in synchronism of the two clocks
without the risk of stopping the action of the same, and I can in general apply my
improved synchronising gear to electric meters without affecting the constant or
calibration of the same.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
Connecting the pendulums or other oscillatory parts of a clockwork electric
meter by a system of strings or cords with or without a centre weight substantially
as described for the purpose specified.
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.