Year: 1888

page_text: Date of Application, 1th Jan., 1888
Complete Specification Left, 8th Oct., 1888
Complete Specification Accepted, 9th Nov., 1888
We, THOMAS PARKER of the Firm Elwell-Parker Limited and EDMUND REES
both of Commercial Road Wolverhampton in the County of Stafford Electrical
Engineers, do hereby declare the nature of this invention to be as follows :-
This Invention relates to apparatus for measuring registering recording and
indicating continuous or alternating currents of electricity.
In carrying out our Invention we employ the heating effect of an electrical current
to evaporate a fluid contained within vessels carried upon the periphery of a disc or
wheel or the equivalent thereto. The heating effect is confined or limited to a segment
upon one side of the wheel and so arranged that the evaporation shall be proportional
to the current; the remainder of the wheel and the vessels thereon are exposed to the
atmospheric temperature. The interiors of the vessels are connected so that as
evaporation takes place the vapour may pass from the heated vessels to the cool ones
where it is condensed.
From the displacement of the fluid from one to the other side of the wheel,
disc or its equivalent, it follows that a rotation of the wheel will be set up, and since
the rapidity of rotation depends upon the greater or less intensity of the evaporative or
heating effect, which is proportional to the current, it follows that the rate of rotation
will also be proportional to the current. The current therefore may be measured,
registered, recorded, and indicated by means of the motion of rotation of the disc or
wheel which operates well known devices ordinarily used for similar purposes.
Dated this 5th day of January AD 1888
WILLIAM E. HEYS,
Agent for the Applicants.

page_text: A New or Improved Electric Meter.
We THOMAS PARKER of the Firm Elwell-Parker Limited and EDMUND REES both
of Commercial Road Wolverhampton in the County of Stafford, 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:―
This Invention relates to apparatus for measuring, registering, recording and
indicating continuous or alternating currents of electricity.
In carrying out our Invention we employ the heating effect of an electrical current to
evaporate a fluid contained within vessels carried upon the periphery of a disc or
wheel or the equivalent thereto. The heating effect is confined or limited to a segment
upon one side of the wheel the remainder of the wheel and the vessels thereon are
exposed to the atmospheric temperature. The interiors of the vessels are connected so
that as evaporation takes place the vapour may pass freely into all the vessels. In
consequence of the lower temperature of the vessels exposed to the atmosphere the
vapour will be condensed in these vessels more copiously than in the others, and these
vessels in consequence of the addition to their weight will descend and it follows that
a rotation of the wheel will be set up, and since the rapidity of rotation depends upon
the greater or less intensity of the evaporation or heating effect it follows also that the
rate of rotation will be in some degree proportional to the current. The current
therefore may be measured, registered, recorded, and indicated by means of the
motion of rotation of the disc or wheel which operates well known devices ordinarily
used for similar purposes.
In the accompanying drawings, Fig. 1 represents a vertical, and Fig. 2'a horizontal
section of the meter constructed according to these Improvements. The devices
which may be used for registering the number of rotations of the vessels are not
represented as their nature and construction are well understood.
A. A are the vessels which are included in a closed ring mounted upon the spindle B.
C is a coil through which the current or a known portion of the current to be measured
passes giving rise to the heating effect. D is a wooden or similar casing surrounding
a portion of the ring of vessels and the heating coil C. This casing is open at the top
and has openings formed near the bottom so that the air may circulate as indicated by
the arrows. The casing D is surrounded by an external casing E constructed of
copper or other metal of good conductivity. F is a metal shield protecting the vessels
on that part of the wheel or ring which are exposed to the external temperature.
Looking at the vessels which are upon that side of the wheel which is exposed to the
external temperature, it will be seen that the lower part of each vessel consists of an
annular trough which in that position will catch and retain any vapours that may be
condensed in them. On the other side of the wheel these annular troughs are inverted
and any fluid condensed therein would flow freely back to the bottom of the wheel.
The presence of the fluid in the annular troughs on the exposed side of the wheel will

page_text: give this side of the wheel a greater weight and tend to set up a rotation of the wheel
the rate of which will be proportionate to the evaporative and cooling effects which
may be at the time operative. We prefer to use as the fluid to be evaporated,
Sulphuric Ether or other similarly volatile liquid.
In Fig. 3 is represented diagrammatically, an automatic shunt for short circuiting
the heating coil through resistances as the current and consequently the heat of the
coil increases and for cutting out the short circuit resistances as the current and heat
diminish. The use of such an accessory is desirable inasmuch as the rotation of the
wheel resulting from the evaporation and condensation, is not directly proportional to
the current or heating effect. C is the coil as in Figs. 1 & 2. G is a bulb and
stem containing mercury. H H are resistances which are electrically connected to
pairs of opposed platinum wires fused into the stem; each resistance circuit is
connected to the lead and to the return wire of the coil. The bulb containing the
mercury is placed in such a position that it may be heated by and cool with the coil.
If the heat of the coil is increasing, the mercury will expand and travel along the tube
until it comes into contact with the pair of platinum wires which are connected to the
first resistance circuit. This resistance circuit is thereby closed and a portion of the
current is diverted through it from the coil and the heating cause in the coil is
diminished. If the current is of such a strength that the heat still increases the
mercury continues to expand and will successively close the following shunt resistance
circuits until the heat of the coil becomes constant. On a reduction of the temperature
of the coil the shunt resistance circuits are successively opened by a reversal of the
previous conditions and the opposite result is secured.
We desire it to be understood that we do not limit ourselves to the precise form
and arrangement of the ring of vessels illustrated by the accompanying drawings as
these may be considerably varied without departing from our Lisvention.
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
(1) An Apparatus for measuring, registering, recording and indicating continuous
or alternating currents of electricity constructed and arranged as hereinbefore
described with reference to the accompanying drawings.
(2) In an Electric Meter, a closed ring of vessels containing a volatile liquid capable
of being evaporated by a heated coil or conductor of electricity and of being
condensed at atmospheric temperature, substantially as and for the purpose herein-
before described.
Dated this Fourth day of October AD 1888
WILLIAM E. HEYS,
Agent for the Applicants.