IMPROVEMENTS IN The Construction of PianOPORTES
Year: 1875

page_text: LETTERS PATENT to Edward Thomas Burling, of Goswell Road, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN
The Construction of PianOPORTES.”
Scaled the 20th April 1875, and dated the 19th February 1875.
PROVISIONAL SPECIFICATION left by the said Edward Thomas
Burling at the Office of the Commissioners of Patents, with his
Petition, on the 19th February 1875. ·
I, EDWARD THOMAS BURLING, of Goswell Road, in the County of
Middlesex, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN THE CONSTRUCTION OF PIANOFORTES," to be as follows:-
-
My Invention relates to improvements in the construction of piano-
fortes, whereby greater accuracy and facility in tuning is obtained, and
the tension of the strings is brought to bear directly on the ends of the
bars or bracings of the frame, thereby avoiding the deflecting strain
consequent on attaching the strings to pins projecting from the front or
face of the wrest plank, as usual, and rendering the frame less dependent

page_text: of temperature and humidity.
I will first describe my Invention as applied to an upright pianoforte.
I transpose the usual position of the wrest pins and hitch pins, the
former being fixed in an angle iron embracing the lower part of the frame,
whilst the latter are fitted in turning levers, whose fulcrum is on a metal
plate fixed on the top ends of the bracings. The levers are adjusted by
tuning screws tapped into a metal head cast with or fixed to the said
plate.
By using straight or cranked levers, and a suitable construction of the
head, the tuning screws may be vertical or horizontal to admit of tuning
either on the top or in front. The hitch pins are fitted to turn like wrest
pins, to correct any inaccuracy of unison, and they are hereafter called
unison pins.
In stringing the pianoforte each string is doubled and looped over its
unison pin, and the two ends are attached to the wrest pins in the
bottom plate, by which the double string is drawn up above pitch. The
instrument is then tuned by means of the tuning screws and levers at
the top, each of which acts on both parts of the double string simulta-
neously, any inaccuracy in unison between the two strings being cor-
rected by turning the unison pin.
The metal head or plate at the top and the angle iron at the bottom
are tied together by bolts introduced between the bracings or upright
timbers of the frame to bring the strain of the strings wholly in the
longitudinal direction of the bracings.
To enable persons unacquainted with the ordinary method of tuning
pianos to tune their own instruments I provide a series of metal tongues
tuned to the required scale, and placed opposite their relative notes,
which can be tuned in unison with them.
The same method of holding and tuning the strings is applicable in
horizontal pianofortes, the metal head in which the levers are fulcrumed
being suitably modified in form and sustained against the tension of the
strings by abutments or shoulders formed on the under side of the bars of
the frame.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Thomas Burling in the Great Seal Patent
Office on the 19th August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
THOMAS BURLING, of Goswell Road, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of February, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Edward Thomas Burling,
Her special licence that I, the said Edward Thomas Birling, my exe-
cutors, administrators, and assigns, or such others as I, the said Edward
Thomas Burling, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF PIANOFORTES," upon
the condition (amongst others) that I, the said Edward Thomas Burling,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Thomas Burling, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the two accom-
panying Sheets of Drawings and to the letters and figures marked
thereon (that is to say) :-
My Invention of improvements in the construction of pianofortes has
for its object to facilitate the accurate tuning of the instrument. It has
also the further advantage that the pull of the strings is brought to bear
directly on the ends of the bracings of the frame, thus avoiding the

page_text: deflecting strain to which the frame is subject when the strings are
attached to pins projecting from the face of the wrest plank, as usual,
and rendering the frame less dependent for strength on the use of glue,
which is liable to be affected by extremes of temperature and humidity.
I will describe my Invention as applied to an upright pianoforte. The
wrest pins are placed in the position usually occupied by the hitch pins,
being fixed in an angle iron embracing the lower part of the frame, and
in lieu of the ordinary wrest plank and pins. I provide tuning levers
fulcrumed on a metal plate fixed on the top ends of the bracings. To
these levers the strings are attached by being looped over pins resembling
hitch pins fixed in the levers. These pins are fitted to turn like wrest
pins to enable any inaccuracy of unison to be corrected, and they are
therefore called unison pins. The strings may however be otherwise
attached. The levers are adjusted by tuning screws, and by using
straight or bell-crank levers. The tuning screws may be vertical or
horizontal to admit of tuning either on the top or in front, as preferred.
The wrest pins in the bottom plate serve for stretching the strings and
roughly tuning the instrument (when it is first strung), the tuning
being afterwards perfected by means of the tuning screws and levers at
the top, by which also all subsequent tuning is effected.
. In pianofortes for extreme climates the metal head or plate upon
which the levers are fulcrumed and the angle iron at the bottom are tied
together by bolts introduced between the bracings or upright timbers of
the frame to bring the strain of the strings wholly in the longitudinal
direction of the bracings.
In horizontal. pianofortes the metal head in which the levers are
fulcrumed is sustained against the tension of the strings by abutments or
shoulders provided on the bars of the frame.
In order that my Invention may be more readily understood I have
illustrated it in the accompanying Drawings, in which,-
Figure 1 represents in transverse section and front elevation so much
of an upright pianoforte as is necessary to illustrate one arrangement of
my Invention.
Figures 2 and 3 show slightly modified arrangements also applied to
the upright form of pianoforte; and Figure 4 shows one form of the a
Invention applied to the horizontal or grand pianoforte.

page_text: In all these Figures the same letters of reference indicate the same
parts wherever they recur.
a the strings; b, the wrest pins replacing the ordinary hitch pins, to
which the ends of the strings are attached at the bottom of the instru-
ment; c are the tuning levers to which the strings are attached at top;
these levers each work on a fulcrum c¹, and in Figures 1, 2, and 4
each lever c sustains a doubled string, which is attached by passing
round a pin d fixed in lever c, termed a unison pin. In this case the
lever c of course acts on both lengths of the doubled string simulta-
neously, any inaccuracy in unison being corrected by turning the unison
pin d. In Figure 3 each string is sustained by a separate lever, and the
string is differently attached. This Figure shows the combination in
the same pianoforte of the bell-crank and straight levers shown in
Figures 1 and 2. e are the tuning screws which operate the levers c;
they are received in corresponding holes tapped in the cast-iron head f
which extends completely across the instrument. The screw e may be
variously arranged, as shown.
In Figures 1 and 3 the levers c are forked or slotted for the passage
of the screw, and the screw is provided with a shoulder e¹, which bears
against the lever, whilst in Figure 2 the end of the screw bears directly
upon the lever. The tuning screws e and unison pins d are squared to
receive the ordinary tuning hammer by which they are tuned. g are
bolts introduced between the bracings h (in pianofortes intended for
extreme climates) to tie together the head fand the angle iron i at the
bottom of the instrument, which in this case extends quite across the
pianoforte. For ordinary instruments the angle iron i would extend
along the bass portion of the instrument only, and the metal head ƒ
would be attached to the bracings h either by a short bolt, as in Figure 3,
or it would be merely an L shaped angle iron, and bolted to the bracings,
as shown in dotted lines Figure 1.
In Figure 3 the metal plate f is made much lighter, the screws
working partly in the wood. In this arrangement the strings are attached
each to a separate lever, so that one string only may be tuned at a time.
The string is attached by being passed through a hole in the end of the
Jever, and twisted on itself, as shown. This arrangement may also be
adapted for a trichord" by providing a unison pin d on one of the
levers (as shown in dotted lines), and passing a doubled string round it,
a single string being attached to the other lever.

page_text: In Figure 4 the metal casting is modified in form to adapt it to the
horizontal construction of pianoforte. In this case the cranked form of
lever only would be employed for "bichords," in order that the tuning
screws and unison pins may occupy the same position as the ordinary
wrest pins.
For trichords however the arrangement shown in Figure 3 would be
adopted, the tuning screws of the straight levers being in that case at
the front. The levers, tuning screws, and unison pins are the same as
before described, and need no further description. I is one of the cast-
iron bars of the frame, each of which bars is provided with two shoulders
m, m, against both of which the casting abuts, as shown.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as the Invention to be
protected by the herein-before in part recited Letters Patent is,-
1st. In a pianoforte the use of levers controlled by screws, substantially
as and for purpose herein set forth.
2nd. The combination with the levers and regulating screws of the
unison pins, as and for the purpose set forth.
3rd. The combination with the levers c, screws, and metal head ƒ of
the tie bolts and angle iron for sustaining and counteracting the pull of
the strings, and avoiding any deflecting strain on the bracings, as
described.
In witness whereof, I, the said Edward Thomas Burling, have
hereunto set my hand and seal, this Eighteenth day of August,
in the year of our Lord One thousand eight hundred and seventy
five