Improvements in Pianofortes
Year: 1898

page_text: Date of Application, 6th Dec., 1898-Accepted, 2nd Dec., 1899
COMPLETE SPECIFICATION.
Improvements in Pianofortes, .
I, ANTON MEDLIK, of Stärkengasse, Dresden A, Saxony, Musical Instrument
Manufacturer, 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 a pianoforte in which the sounding board is of a
double construction forming a single undivided part and tuned to correspond to
the sound graduation of the strings, and in which the fixing of the strings over
the double sounding board is accomplished so as to relieve it from the strain of the
strings and allow it to vibrate freely and thereby improve and strengthen the
tone or sound, said sounding board for the purpose of facilitating repairs and for
other purposes being removable from its metal frame from behind without the
necessity of slackening or displacing the strings at their places of attachment to
the wrest plate or sounding board frame or of tightening them at those places
when the sounding board is replaced in position; and further in which the string
bridge on the wrest plate is so insulated from the frame that it cannot give out
sound. Another feature of the invention by which al material advan-
tage is gained is an arrangement of string support on the double sounding board
and wrest plate for sharply limiting the effective sounding string length for the
purpose of obtaining a clear tone. The invention also relates to a method of
attaching sides to the frame.
In the accompanying drawings Fig. 1 is a front view of the double sounding
board referred to and Fig. 2 is a section of the same on line y-y of Fig. 1.
Figs. 3 and 4 are respectively a front and a back view of the double sounding
board placed in its frame.
Fig. 5 is a section on line 2-2 of Fig. 3.
Fig. 6 shews a portion of Fig. 5 on an enlarged scale.
Fig. 7 is a cross sectional view of the string pressing arrangement on the
Eounding board.
The sounding board is composed of two bulged out or arched sides a, b, which
are glued to a correspondingly curved edge piece o said sides being provided with
a rib (Fig. 2) of a strength suitable for holding them in their bulged position.
They are made of wood with the fibres running in the direction of the section
line yy of Fig. 1 whereby the tone is improved.
By reason of the peculiar construction of the double sounding board the same
sounds conformably to the graduation of sound of the strings stretched over it
at a given place and consequently strengthens and improves the tone of the
string.
The side piece of the sounding board is provided with one or more sound
orifices and has fixed to it curved strips e, f, which carry double string rest rails g
provided with steps or notches (a portion of which are shewn) for groups of strings
said rails and the steps formed in them are held so that the actual sounding string
length between the string support and the sounding board and that on the wrest
plate is precisely and sharply limited thereby enabling a very clear, full, and
sonorous tone to be produced.

page_text: Instead of the usual method of fixing the strings by means of zigzag placed
studs, they are here fixed on the sounding board by pressing strips adjustable
by screws towards or away from the rails g,. by which pressing strips the
strings k, a few only of which are shewn for the sake of clearness, are stretched
on the two supporting points of the rails g (Figs. 6, 7). This method of mounting
the strings on the double sounding board presents the advantage that the latter
is relieved from the pressure of the strings and consequently can vibrate more
freely and give out a clearer and better tone. Further there is the advantage
that when, for repairing or other purposes, the sounding board is to be taken
out, this can be done without slackening or displacing the strings at the other
fastening places on the frame and wrest plate 7, it being only requisite to
remove the pressing strips by unscrewing the screws in order to set free all
the strings whereupon the sounding board, after being unfastened at its places
of attachment to the frame, can be taken out at the back of the latter, and when
replaced it is only necessary to return the pressing strips to their place and
stretch them as before to produce the same tone as before.
The frame has two large apertures m through which the supporting rails
and pressing strips i can pass to the front (Fig. 3). The circular apertures m
serve to develope or expand the tone.
In addition to the adjustable pressing strips i, a similar strip n is attached to
the wrest plate by screws o said pressing strip serving to hold down the strings
between the cushion and the wrest plate bridge q. By reason of the strings
being thus pressed down by the pressing strip the tone is greatly improved.
For the bass strings a similar pressing strip n is not employed because they
do not cross their supporting bridge at right angles and for this reason are set
by pins s.
The wrest plate bridge which limits the sounding length of the strings
between it and the supporting rails g,. instead of being formed in one piece as
hitherto, is provided with a wood base let into the iron frame and adapted
to be removable and interchangeable, said wood base serving as an insulator
between the bridge and the frame to prevent the latter sounding with the
strings, thereby insuring a clearer tone.
Like the supporting rails g, the interchangeable wrest plate bridge 7 is held to
stand out sharply to sharply limit the effective string length for the production
of a clear tone.
The double sounding board is fixed in the frame by means of screw bolts t
which are passed through the sides a, b, the intermediate edge c, and into the
frame.
In order that the arched sides of the sounding board may bed properly against
the frame and against the screw bolt nuts, wedged shaped packing pieces w
(Fig. 6) are provided.
w are dovetail recesses in the side edges (Fig. 4) of the frame in which
wood pieces are inserted to facilitate the fixing of wooden sides to the frame by
glueing.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1. A pianoforte, which is provided with a double sounding board forming a
single undivided part so constructed and arranged that it sounds according to the
string musical graduations and in which the connection of the strings with the
double sounding board is so accomplished by means of string pressing and stretch-
ing strips that the sounding board is free from string pressure, can vibrate
freely whereby the tone of the instrument is improved, and is removable and
replaceable for the purpose of repairs and other purposes without it being neces-
sary to slacken or displace the strings at their places of attachment on the wrest
plate and frame 1, substantially as described and shewn.

page_text: 2. In the pianoforte referred to the arrangement of the removable string bridge q
placed on a wooden base on the wrest plate h which base serves as an insulator
to prevent the frame from sounding and thus to obtain a clear tone, substan-
tially as described and shewn.
3. In the pianoforte referred to, the arrangement for limiting the effective
sounding length of the strings in a sharply defined manner, consisting in the
string supporting rails g, bridge g and strips i, n, which strips press upon and
hold the strings upon said rails and bridge for the purpose of obtaining a full,
clear, and sonorous tone, substantially as described and shewn.
4. In the pianoforte referred to, the provision in the side edges of the frame/
of dovetail recesses filled in with wood pieces for the purpose of facilitating the
fixing of sides to the frame by glueing them on the side edges, substantially as
described and shewn.
Dated this 6th day of December 1898.
THOMAS R. SHILLITO,
15, Tooks Court, London, E.C., Agent for the Applicant.