Improvements in Electrical Indicating and Recording Meters.
Year: 1895

page_text: Date of Application, 11th Nov., 1895
Complete Specification Left, 10th Aug., 1896--Accepted, 3rd Oct.,
1896
PROVISIONAL SPECIFICATION.
Improvements in Electrical Indicating and Recording Meters.
We, REGINALD JOHN CUMMING WOOD of 24 Sinclair Road, West Kensington,.
in the County of Middlesex, Electrical Engineer, and ARTHUR EDWARD MAYES
of Raleigh House, Ford End Road, Bedford, in the County of Bedford, Electrical
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to that class of recording meters in which the record is
kept upon a moving band of paper or the like, and the invention may be equally
well employed where both a paper or like record and an index are used.
The nature of the invention will be understood from the following description:
In lieu of employing a pen, pencil or stylus over the moving strip of paper, it
is proposed to record or mark such paper or other material by means of nu electric
spark, the current for which passes from the index point upon one, side to a metallic
plate placed upon the other side of the paper. The sparks in such case would
Above
either perforate or discolour the band and thus present a complete record.
the top sparking point may be placed the index finger adapted to move in front
of a suitable graduated scale. The paper or record strip is preferably moved by
clockwork mechanism acting on a drum, the strip passing over two rollers between
which is placed the lower sparking plate, while between one of the rollers and the
drum may be placed the tightening finger or roller in order that the paper may be
kept sufficiently taught when in use and may yet be readily removed and a new
sheet inserted.
In practice such index and record may be applied to many electric systems, say
for example to an electric light system in which the ordinary voltage is say
about 100. In such a case a transformer or induction coil would be employed
whereby the potential difference of 100 volts would be transformed into say
2000 volts for the purpose of producing the requisite sparking in the apparatus,
which apparatus would also be connected electrically with the electric system.
In construction it will probably be preferable to make that part of the instrument
which consists of the drum and rollers mechanically distinct from the index finger
and top sparking point in order that it can be readily removed to change the paper
or strip without the calibration of the measuring instrument being likely to be
altered, although during such removal the index finger would still continue to
indicate the potential difference, current or energy being measured. The opening
of the case is preferably so arranged as to cause the high tension circuit to be
broken, thus ensuring safety in manipulating the instrument.
When
The invention is applicable as a recording volt, current or Watt ineter.
used as a recording volt meter it is preferable to use an electro-static volt ineter as
the power absorbed in the whole instrument is a minimum. The sparking plate is
insulated from the frame but the needle or top point is electrically connected to
the Irame of the measuring instrument which is insulated from the main frame.
Dated the 11th day of November 1895.

page_text: Improvements in Electrical' Indicating and Recording Meters.
We, REGINALD JOHN CUMMING WOOD formerly of 24 Sinclair' Road, West
Kensington in the County of Middlesex, but now of Los Angelos, California,
Electrical Engineer, and ARTHUR EDWARD MAYES formerly of Raleigh House,
Ford End Road, Bedford, but now of Whitfield House, Whitfield, in-the County
of Kent, Electrical Engineer, do hereby declare the nature of this invention and
in what manner the same is to' he performed, to be particularly described and
→ ascertained in and by the following statement:-
This invention relates to that class of recording ineters in which the record is
kept upon a moving band of paper or the like, and the invention may be equally
well employed where both a paper or like record and an index are used.
The nature of the invention will be understood from the following description.
In lieu of employing a peu; pencil or stylus over the moving strip of paper it is
proposed to record or mark such paper or other material by means of an electric
spark, the current for which passes from the index point upon one side to a metallic
plate placed upon the other side of the paper. The sparks in such case would
either perforate or discolour the band and thus present a complete record. Above
the top sparking point may be placed the index finger adapted to move in front of
a suitable graduated scale. The paper or record strip is preferably moved by
clockwork mechanism acting ou a drom, the strip passing over the two rollers.
between which is placed the lower sparking plate, while between one of the rollers
and the drum may be placed the tightening finger or roller in order that the paper
may be kept sufficiently taught when in use and may yet be readily removed and
a new sheet inserted.
In practice such index and record may be applied to many electric systems, say
for example to an electric light system in which the ordinary voltage is say
about 100. In such case a transformer or induction coil would be employed
whereby the potential difference of 100 volts would be transformed into. say
2000 volts for the purpose of producing the requisite sparking in the apparatus,
which apparatus would also be connected electrically with the electric system.
To clearly explain our invention reference is made to the accompanying
drawings in which :-
"
:-
Fig. 1 is a front elevation of a voltmeter showing one manner of carrying our
invention into effect.
Fig. 2 is a side elevation of same.
Fig. 3 is a plan of the sparking plate.
Fig. 4 is a section of the roller on which the paper for the record is carried, and
Figs. 5 to 8 are diagrams showing various electrical connections of the apparatus
according to some of its different uses.
The measuring portion of the instrument is contained in a case a and may be of
any known suitable kind for measuring the potential difference, current or energy.
6 indicates on this the needle, and c the axis of same, d being the index in front of
which the index finger e is situated, such. finger moving with the movement of the
needle.
We preferably form the recording portion of the apparatus distinct from the
measuring portion as above in order that it can be readily removed to change
the paper or for other purposes, without the calibration of the measuring
instrument being likely to be altered and so that during such removal the index
finger will still continue to indicate visibly the potential difference, current; or
energy, being measured. For this purpose the case a is mounted on an insulated
materialy carried by a bracket g. The recording instrument which is contained
in a framework is supported by three adjustable screws iii, the two in front

page_text: [seating one in a V shaped groove and the other in a hole in the bottom of the
bracket, and the one in the rear resting on a flat surface, the arrangement
enabling the recording portion of the instrument after removal to be
put back into the same position that it occupied before. The frame h carries
on a spindle the roll of paper for the record. The spindle is mounted
on centres consisting of the coned points of adjustable screws, the paper
being wound upon a tube of cardboard or some light material m (Fig. 4)
which can be slipped on to the spindle and held in place by an adjustable
cone m¹ and a fixed cone m', the arrangement enabling a fresh roll of paper to
be easily substituted. From the roll the paper o passes over a roller n carried on
centres formed by the points of adjustable screws n', a tension device being
employed at this point consisting of bent levers p carrying a roller p between them
and pivoted on a rod p', the short arms of the levers' carrying weights p³ hung on
same, the position of such weights being varied according to the pressure it is
desired to put upon the paper o.
From the roller n the paper passes in a
horizontal direction over a sparking plate 7; or it may be a number of sparking
points though we prefer the plate. This as shown in Fig. 3 consists of a plate
having a shaped ridge or projection g¹ thereon, such ridge being a segment of a
circle which corresponds to the curve described by the needle and index finger e.
The plate is supported on insulating blocks g of highly insulating material at
either end, such blocks separating it from the framework. The index finger'e
carries beneath it a sparking point el which is over the ridge q² and is separated
from it by the paper o. The paper now passes over a roller carried on the point
of adjustable screws n³, and from thence' passes down vertically between a drum'r
(which may have rubber bands around it) and a pressure roller carried by
arms pivoted at, the arms and roller being pressed against the drums by a
spring actuated curved rod or strip & the pressure of which can be regulated by an
adjusting screws at the front of the apparatus. Various other means may
however be employed for putting the pressure or tension on the rollers and p²,
the object of such tension being to keep the paper flat and out of contact with the
sparking point and flat on the sparking plate. The paper passes between the
rollers and drum r and out below the same, or if a case is employed through a slot
in the case.
The means employed for drawing the paper consist of a spur wheel t
with which engages a pinion t driven through a spur wheel of a suitable train
of clockwork contained in a case u. The case may be held in position by ear
pieces carried by a stay v', the ear pieces having slots in same through which
pass screws r. The arrangement enables the case to be moved back to disengage
the pinion from the spur wheel when it is not required to drive the drum r.
The paper is ruled with curved lines which correspond to the curve which the
sparking point may travel through, and such paper is also divided up vertically
into lines which correspond to the divisions on the index of the measuring
instrument, and it may also be marked at the edges to indicate hours and divisions
of same or any periods of time which may be required so that the record will
show not only the variations of the needle but the times at which such variations
occurred.
t
The record is made by the spark passing from the sparking point (which is
connected electrically with the measuring instrument) to the sparking plate through
the paper, the spark thus perforating or discolouring the sheet so that a continuous
record is presented. To prevent the paper from being entirely divided by the
spark, lines of some insulating substance may be ruled across the same if desired,
and stops limiting the play of the needle may be employed. To produce the spark
a small transformer or induction coil may be used in the low tension circuit of
which a resistance or choking coil is put so that the current in the spark gap
cannot rise beyond a certain value. The high tension winding of the transformer
should be highly insulated from the low tension and the iron.
A case with a glass front may cover both the measuring and recording.
instruments, the case being so arranged that when taken off it breaks by means of

page_text: a switch, the transformer circuit thus ensuring safety and ease in manipulation,
the index finger however may still continue to indicate on the graduated scale
or iudex.
The instrument it will thus be seen is capable of recording electric difference of
potential, current, or energy with great sensitiveness (there being no friction
between the sparking point and sheet) and with a small amount of energy while it
also provides in one instrument both a visible and a permanent record of the
variations of the needle. For measuring and recording difference of potential
between any point of an electric system the use of an electrostatic volt-meter
ensures a minimum amount of energy being expended.
The diagrams Figs. 5 to 8 show the electrical connections with various forms of
measuring instruments,
Fig. 5 illustrates the connection when using an electro-tatic volt meter, C being
the case, e the sparking point, q¹ the sparking plate, 1 points.on an electric
system whose difference of potential is to be measured or recorded, T the
transformer, S a switch closed by putting on the case, Ra resistance in series with
the low tension circuit of transformer, and 1 the inductors of volt-meter insulated
from case, the latter being insulated from the frame.
Fig. 6 shows the connections when using a volt-meter taking current, the parts
being similar to those in Fig. 5 except that the coil is joined as shown. The
arrangement applies for volt-meters with fixed or moving coils.
Fig. 7 shows the connections for au amineter, I being the coil of the latter.
Fig. 8 shows the connections for a Watt-meter, I being the fixed coil, aud I* the
moving coil.
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. In an electric meter the means for producing a record ou a strip of paper,
consisting of a sparking point and a sparking plate or its equivalent between which
the paper is caused to travel, substantially as described.
2. In an electrical indicating and recording meter the means for producing a
record on a strip of paper consisting of a sparking point and a sparking plate or
its equivalent between which the paper is caused to travel, said sparking point
being carried by the index finger or needle of an electrical measuring instrument,
substantially as described.
3. In an electric meter a sparking point, a sparking plate or its equivalent, a
strip of paper, means for drawing the strip between the point and plate, and means
for putting a tension on the paper for preventing it touching the sparking point,
substantially as described.
4. In an electrical indicating and recording meter a measuring instrument &
bracket or the like for supporting and insulating the same, and a recording
instrument carried by said bracket, said recording instrument carrying a strip of
paper which passes between a sparking point and a sparking plate or its equivalent
adapted to make a record on the paper, said sparking point being attached to or
forming part of the needle or index of the measuring instrument, substantially as
described.
5. The improved electrical indicating and recording meter substantially as
described and illustrated.
described and illustrated.
Dated the 10th day of August 1896.
For the Applicants,
PHILIP M. JUSTICE,
55 & 56 Chancery Lane, London, Chartered Patent Agent.