Improvements in Recording Instruments.
Year: 1889

page_text: Date of Application, 8th Oct., 1889
Complete Specification Left, 7th July, 1890-Accepted, 23rd Aug., 1890
Complete Specification Left, 7th July, 1890-Accepted, cord A
PROVISIONAL SPECIFICATION. ·
Improvements in Recording Instruments.
We, BERNARD MERVYN DRAKE and JOHN MARSHALL GORHAM, Electrical
Engineers, both of No. 2 Princes Mansions, Victoria Street, S.W. in the City of
Westminster do hereby declare the nature of this invention to be as follows:-
The object of our invention is to provide a reliable method of recording the move-
ments of a needle or index without the friction which attends the ordinary appliances:
For this purpose we arrange an electro magnet with an intermittent make & break
circuit which is utilized to attract an armature pivotted or suspended in such a way
that the attraction of the magnet will press the needle against the paper and cause it
to leave a permanent record. After each stroke the needle is again free to take up a
new position before the next record: The most convenient form is to employ metallic
paper & to fix the magnet & armature on opposite sides of this, the needle moving
near the paper bat not touching either the magnet or the paper except when_strúck-by
the armature.
T
TA
1006
COMPLETE SPECIFICATION.
Improvements in Recording Instruments.
We, BERNARD MERVYN DRAKE, and JOHN MARSHALL GORHAM, Electrical
Engineers, both of No. 2 Princes Mansions, Victorin Street S.W. in the City of
Westminster, 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:
After each
The object of our invention is to provide a reliable method of recording the move-
ments of a needle or index without the friction which attends the ordinary appliances.
For this purpose we arrange an electro-magnet with an intermittent make and break
circuit arrangement which is utilized to attract an armature pivotted or suspended in
such a way that the attraction of the magnet will cause the armature to press the needle
or indicator against the paper, and cause it to leave a permanent record.
stroke the needle is again free to take up a new position before the next record. The
most convenient form is to employ metallic paper and to fix the magnet and armature
on opposite sides of this, the needle moving near the paper but not touching either
the armature or paper except when struck by the armature. Or, again this may be
done mechanically by means of a striking arrangement working at regular intervals,
and a plate placed on opposite sides of the paper, the needle being perfectly free as
before except when struck by the striker.
In the case of paper running over rollers an accurate method of dividing or
calibrating the same is to employ metal points pressing against the paper, which will
leave lines on the paper, which will be correct with regard to the record, irrespective
of the uneven running of the paper on the rollers.
Referring now to the drawings, in Fig. 2 & 3,-A is the needle or indicator fitted
with a blunt point B, preferably of metal. The needle moves freely about centre C,
being near the paper but not touching it. D is the paper running over rollers and
across the face of the metal plate E fixed to the poles of the electric magnet F which
1 is
is excited at regular intervals by means of the battery G and circuit breaker H.
the armature fixed on springs J J which normally keep it clear of the needle A.
When the contact breaker H closes the circuit round the electro-magnet F the
D
"

page_text: armature I is attracted and strikes the needle A against the paper D the point B
making a permanent record as shewn at K. Immediately on the circuit being
broken at H the armature flies back to its original position leaving the needle A. free
to move until the next record.
Referring to Fig. 1. A mechanical arrangement is shewn in place of the electro-
magnet and armature. L is a metal striker fixed on springs M and moving about
centre N. Normally this striker L is kept some distance away from the needle A by
the cam wheel O which may be driven by the same means as the paper. At certain
regular intervals this cam wheel O allows the spring P to draw the striker L forward
striking the needle A against the paper D the point B making a record as before.
Immediately after the blow the striker L flys back to the dotted position, and is
gradually forced back by the cam wheel O till ready for the next record.
In figures I, II, III, Q, Q, Q, are a row of metal points pivotted at point R and
kept pressed against the paper D by springs S-these mark the paper off into any
required divisions as it runs, and obviate any irregularity in the record due to the
paper running unevenly.
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-
I. The use in recording instruments of an electro magnet and armature for the
purpose of avoiding friction and making an intermittent record substantially as
described.
II. The application of an intermittent mechanical striker to the index of recording
ammeters and voltmeters substantially as described.
III. The use of a comb or marking arrangement in connection with a recording
instrument for calibrating or dividing the paper at the same time that the record is
being taken substantially as shown in accompanying drawings.
Dated this 7th day of July 1890.
BERNARD MERVYN DRAKE.
JOHN MARSHALL GORHAM.