Year: 1886

page_text: Date of Application, 24th Dec., 1886
Complete Left, 26th Sept., 1887
Complete Accepted, 28th Oct., 1887
I, HERMANN COHN, of London Wall, in the City of London, Merchant, do hereby
declare the nature of this invention to be as follows:-
This invention relates to methods of tuning the strings of pianos or other stringed
instruments, in which the string or wire is stretched or slackened as required by
turning a screw, instead of the wire being wound round a pin as in the ordinary
method.
The wire holding device consists of a cylindrical plug to which the end of the
wire is attached by pushing its end into a transverse hole drilled through the plug
near its upper end the wire then passing down a groove at the side of the plug,
round its end, and up a corresponding groove at the other side. The plug having
the wire attached to it is then driven into a separate straight tube or pipe so that
the two form a compound plug in which the wire is firmly held and which is then
inserted into a hole in the wrest plank of the piano. A screw having a hexagonal or
other head by which it can be turned is then screwed into the hole in the wrest
plank, its end pressing upon the head of the compound plug, and as the screw is
screwed in it forces the plug in, tightening the string or wire accordingly.
The plug is entirely separate from the screw, and has no lateral projection what-
ever, but one side of the hole in the wrest plank has a groove curved out at its outer
and so as to allow the wire to pass along and out of the hole without being touched

page_text: by the screw, and the upper end of the outer tube of the compound plug is also
notched to allow the wire to pass out.
By the means described the string or wire is very firmly held without the possibility
of slipping, and is stretched or slackened very gradually and easily by turning the
screw in or out.
The "pressure bar" (which generally causes great difficulty in tuning on account
of the string or wire-as is technically termed "hanging on the bar ") can be
entirely dispensed with, the string passing directly from the bridge to the plank.
Dated this 24th day of December 1886.
EDWARDS & Co.,
35, Southampton Buildings, London,
Agents for the Applicant.

page_text: A communication to me from ROBERT THOMPSON, of Christchurch, New Zealand,
Music Seller.
I, HERMANN COHN, of London Wall, in the City of London, Merchant, 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 and accompanying drawings, (that is to say):
This invention relates to the sounding wires or strings of pianos or other
instruments of the like kind, and it has for its object improvements in the method
and apparatus by which the ends of such wires are held and are stretched more
or less for the purpose of tuning them.
In the ordinary system, the ends of the wires are wound round pins or pegs
by turning which with a suitable key the wires are more or less stretched, but
in this arrangement the wires are liable to be broken, great force is required to
turn the key so that it is very difficult to tune the wire exactly, and the wires
are liable to alter in tone by the bending or yielding of the pins or pegs laterally.
The present invention consists of improvements upon the method of holding
and stretching the wire, in which the latter is attached to a cylindrical plug
fitting in a corresponding hole its position in which is altered and adjusted by
means of a screw turned in or out by a key.
The improved wireholding device consists of a cylindrical plug to which the
wire is attached by passing its end through a transverse hole drilled through the
plug near its upper end, the wire then passing down a groove at the side of
the plug, round its lower end, and up a corresponding groove on the other side.
The plug having the wire attached to it is then driven into a separate short
straight tube so that the two form a compound plug in which the wire is firmly
held and which is then inserted into a hole in the wrest plank of the piano, or
in a plate connected to it. A screw having a hexagonal or other head by which
it can be turned is then screwed in above the compound plug so that its end
presses upon the upper end of the latter, and as the screw is screwed down it
forces the plug in, tightening the string or wire accordingly, whilst if it be
unscrewed the wire is slackened, and in this way it can be exactly tuned to the
desired pitch.
The compound plug is entirely separated from the screw and has no lateral
projection whatever but on one side of the hole through which a screw turns as
described, a narrow groove is made curving out at its upper end so as to allow
the wire to pass up and out of the hole without being touched by the screw,

page_text: the upper end of the compound plug being also notched to allow the wire to
pass out.
In the accompanying drawings, which are in illustration of the invention, figure I
is a vertical section of the compound plug with the wire in its place, figure 2 is a
corresponding section through the outer tube, and figure 3 a side view of the
inner plug.
Figure 4 is a section shewing the compound plug and wire inserted into a hole in
the plank, and pressed down by the screw as described, and figure 5 is a view of the
same from above.
Figure 6 shows in section a somewhat modified arrangement, in which metal plates
are used carried by the wrest plank.
Figure 7 is a view from above. Figure 8 is a section on a larger scale, and
figure 9 a view from below of a somewhat modified compound plug; and figure 10
is a view from above, and figure 11 a section of a slightly varied modification of
the same.
is
The same letters of reference indicate the same parts in the several figures.
In figures 1, 2, 3, 4, and 5, a is the wireholding plug to which the wire
attached by pushing its end through a transverse hole drilled through the plug at
its upper end, the wire then passing down a groove at the side of the plug (shewn
in figure 3), then round a similar groove at the bottom, and up a third corresponding
groove on the opposite side. The plug a is then driven into the tube c, until it
touches the bottom of the latter, the two forming a compound plug in which the wire
is firmly held and which is then inserted into a hole in the wrest plank d (figure 4).
A screw e having a hexagonal or other head by which it can be turned (but shewn
broken off) is then screwed into the hole in the plank, its lower end pressing upon
the head of the compound plug a, e, and as the screw e is screwed in, the plug is also
forced down, tightening the string or wire proportionally.
The plug has no lateral projection whatever, but one side of the hole in the plank d
is grooved and curved at its upper end as shown at (figures 4 and 5) so as to allow
the wire to pass along and out of the hole without being touched by the screw e,
and the upper end of the tube c is shewn notched for the same purpose.
In figures 6 and 7 the invention is shewn applied to a piano having a wooden
wrest plank d. To the end of this plank is fitted and firmly secured a metal piece g
through which are bored in the proper positions as many vertical holes as there are
wires to be tuned. These holes are bored perfectly true and parallel, so that the
cylindrical compound plugs to which the wires are fastened can move freely along
them. Upon the upper face of the metal piece is firmly screwed a metal plate h
through which are made vertical screwed holes exactly above the cylindrical holes in
the piece below. A metal screw e of smaller diameter than the holes in the
plate below turns freely and smoothly in the screwed holes in the plate 7. The
screws have hexagonal, square, or other shaped heads, by which they can be
casily screwed in or out by a suitable key. The wires after passing through
and round the slot (as already described) pass over a bridge on the plate h,
their outer ends being secured in the usual way at the other end of the wrest
plank.
In the compound plug, which is shewn in section on a larger scale in figure 8,
the inner plug a has a diagonal groove drilled through it from the upper end of
one of the side grooves (which does not reach to the top of the plug) to the
bottom of the plug, its lower end opening out of the latter not at the centre but
near one side (as shewn in figure 9).
The end of the wire is passed down through the diagonal hole and is then
bent across the bottom of the plug a. The upper part of the wire is then bent
over at an acute angle and brought down the side groove and round over the
end of the wire at the bottom of the plug a, thence passing up the opposite side
groove and out through a notch in the head of the plug.
The plug carrying the wire so arranged is then driven into the tube c until
he flange at its head rests upon the upper end of the latter. The upper loose

page_text: end of the wire b is then introduced through the hole in the plate g (figure 4)
from below and is drawn up bringing with it the compound plug (as shewn .in
figure 6).
The end of the wire is then stretched and made fast at the other end of the
plank d, and the screw e, (of smaller diameter than the compound plug), is then
screwed through the plate from above until its point presses upon the upper
end of the plug a, and it is turned round by a key, pressing the compound plug
and the firmly held end of the wire down and stretching the latter until it is
properly tuned. ƒ (figures 6 and 7) is a narrow groove, well curved and rounded;
through the plate h, opposite each screw-hole, through which the wire b passes
on its way to the bridge, and it will be seen that the wire having no sudden
bend is not liable to injury.
The corners of the different grooves in the plug a are rounded as shown.
In the modification shewn in figures 10 and 11, the diagonal hole through the
plug a is not continued to the bottom of the latter, the end of the wire being
simply inserted into it and then turned down at an acute angle into the vertical
groove at the side of the plug.
By the arrangements and construction described it is impossible that the end of the
wire can slip upon the plug, whilst the wire can be tuned with the greatest ease and
exactness.
The heads of the screws are preferably electroplated with nickel or other metal,
and the holes and grooves in the plugs should be made to properly fit the wire
which they are to receive.
Having now particularly described and ascertained the nature of my said invention
and the manner in which the same is to be performed, I declare that what I
claim is :-
1. The perforated and grooved plug a, with the tube c for the purpose of
securely holding the end of the wire or string b, substantially as described and
shewn in figures 1, 2, 3, and 4.
2. The screw e, screwing into a hole in the wrestplank, against the head of a
compound wire holding plug a, c, formed and arranged as described, and the
groove allowing the wire to pass the scrow, substantially as described and
shewn in figures 4 and 5.
3. The compound plug, consisting of a plug a, having a diagonal hole passing
out at the bottom, and vertical grooves at its sides, in combination with the
external cylindrical tube c, substantially as and for the purpose described, and
shewn in figures 6, 7, and 8.
4. The compound plug, consisting of a plug a, having a diagonal hole passing
out at the opposite side, and vertical grooves at the sides, in combination with
the external cylindrical tube c, substantially as and for the purpose described and
shewn in figure 11.
Dated this 24th day of September 1887.