CERTAIN IMPROVEMENTS ON PIANOFORTES
Year: 1825

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PIERRE
ERARD, of Great Marlborough Street, in the County of Middlesex, Musical
Instrument Maker, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Fifth day of January, in the fifth year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
Pierre Erard, His especial licence that I, the said Pierre Erard, my exors,
admors, and assigns, or such others as I, the said Pierre Erard, my exors,
admors, and assigns, should at any time agree with, and no others, from time
to time and at all times during the term of years therein expressed, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, the Invention of "CERTAIN IMPROVEMENTS
ON PIANOFORTES" (Communicated to me by a certain Foreigner residing abroad);
in which said Letters Patent there is contained a proviso obliging me, the
said Pierre Erard, by an instrument in writing under my hand and seal,
particularly to describe and ascertain the nature of the said Invention, and in
what manner the same is to be performed, and to cause the same to be
inrolled in His Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent (as in and by the same), reference being thereunto had, will more fully
and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Pierre Erard, do hereby declare that the nature of the said "Certain Improve-
ments on Pianofortes," and the manner in which the same are to be produced
and carried into effect, are particularly described and ascertained in and by
the Drawings hereunto annexed, and the following description thereof (that is
to say):―
Having established for the pianoforte in general, by my Patent granted on
the Twenty-second of December, One thousand eight hundred and twenty-one,
a new system of action, which does away with the defects complained of in
the ordinary pianoforte actions, and possesses advantages quite peculiar to
itself, the object of the present Patent is to introduce into the construction of
the pianoforte in general such improvements as are calculated to ensure its
solidity and durability. There are also contained in this Specification several
useful improvements in sundry parts of the mechanism, new in themselves, or
such as may have suggested themselves from the application of my new system
of action to the different species of pianofortes, grand, square, upright, or any
other description of pianofortes, whether the hammer should be made in any
kind of pianoforte to strike the wiro either in a direction towards the sounding
board or away from the sounding board. The defect inherent to the grand
pianoforte in general is the want of stability in the wrest pin plank, which not
being sufficiently secured to the other parts of the case, is by the great
draught of the wires distorted more or less, but generally in such a degree as
to be injurious to the accurate effect of the mechanism on the wires. To
remedy the above-mentioned defect a new mode of construction has been
invented, and I will describe it as follows:-
In Sheet I. of the Drawings hereunto annexed, a, a, Fig. 1 and Fig. 2, is a
piece of sheet iron or other suitable metal introduced between the wrest pin
plank A, A, and the key bottom B, B, which I frame of wainscoat, or any
other firm strong wood in preference to deal. b, b, is another piece of sheet
iron, bent in the shape of a square or elbow, and fixed on both sides to the
upright sheet iron a, a, by bolts or rivets C, or otherwise the elbow pieco
b, b, and sheet iron a, a, are soldered or brazed together, as shewn by the
section Fig. 2, forming a solid piece, which is at top let in the under side of
the wrest pin plank, as seen at b, b, in Figure 2, and firmly fixed to it by
means of screws e, e, e, e, passing through the wrest pin plank, and resting
with their heads on metal plates f,f, sunk into the top of the wrest pin
plank A, A. The upright piece of sheet iron a, a, is fixed and screwed to
the key bottom B, B, in a similar manner as seen at g, g, Figure 1.
I place
between the two sides of the case at convenient distances as many such pieces

page_text: of sheet iron as may be found advisable, as shewn in Figure 3, where four of
the said pieces of sheet iron are represented, and the same letters denote the
same parts as in Figures 1 and 2, so as to unite the wrest pin plank and key
bottom in so firm a manner as to form almost an entire block, and prevent
the twisting and distortion of the wrest pin plank which takes place in the
ordinary constructions. The piece of sheet iron is so shaped as to come up
to the edge of the wrest pin plank, to be fixed at h at pleasure in a similar
manner as the one just described, and the sheet iron a, a, is prolonged in any
part of the instrument where it happens to be situated, as clearly shown in
Figure 3, to the bent side of the case, to which it is firmly secured, as at
e, e, e, e, in a similar manner to that described, or merely by screws entering
the wood, the pieces of sheet iron a, a, Figure 3, dividing the space where
the keys and action are introduced in several parts, as seen at d, d, d, d,
Figure 3. It is obvious that the keys and action must be divided in as many
compartments, and the spaces between the strings must also be divided
accordingly. I further improve the general construction of the instrument
by fixing to each of the above-named pieces of sheet iron at the end near
the bent side of the case, bolts, or riders m, n, Figure 1, so constructed as
to stride over. or embrace the sheet of iron a, a, and be fixed to it by means
of the rivets n, n, n, or in any other convenient manner.
The bolts m, m,
has a head o, o, passing through a hole in the sounding board as at p, p.
That head carries a screw q. 4, which is made so as to press with the requisite
force against the bont side of the caso at r, Fig. 1 and Fig. 8; and to
prevent the end of the screw from forcing itself into the wood, à small metal
plate is applied as at a. To make the whole apparatus almost as strong as
if it were one solid body, I introduce between the several pieces of sheet
iron a, a, other pieces of sheet iron or bolts, or pieces of wood t, t, as shewn in
Fig. 1 and 3. The number of such pieces of metal or wood is quite optional,
and the manner in which they can be fixed may be varied at pleasure, and
need no further explanation than the Drawings. The bolt m, o, may be
lengthened so as to pass through a space between the strings, and made to
press on the bracing contrived above the strings, as shewn at Fig. 4. The
bolt in Fig. 4 is shewn as terminating in a screw, which is meant to screw in
any convenient part of the instrument. A bolt u, nearly similar to the one
just described, and as shewn, Fig. 5, is meant to screw down into the lining's
of the bent side of the case to serve as a firm rest to one end of the long
arch v, and which long arch is firmly joined or secured on it by means of the
screws y; and when I apply the long arches in the bass of the instrument,
where they require to be a certain length, I provent their being twisted by

page_text: the tension of the wires by means of bolts w passing through a hole in the
sounding board, and screwing into the bracing either of wood or metal.
Under the sounding board the long arch is attached or fixed to the heads
(filed sufficiently thin to prevent the wires jarring against it) of the bolt by a
screw passing through the substance of the long arch, and screwing into
such head of the bolt as at . This way of tying together the bracing above
the sounding board with the bracing under the sounding board is calculated to
give a very great solidity to the case of the instrument.
Sheet II. represents a new application of my new system of action, which in
principle is founded on my aforesaid Patent of One thousand eight hundred and
twenty-one, but is new in point of application and arrangement of parts. The
hammer is differently placed from what it is in general in grand pianofortes (see
Fig. 6), having its head a near the centre of the finger key, and its centre of
action 6 further from it. The key is made longer than usual, and the different
pieces performing the operation, instead of being mounted upon an interme-
diate lever between the key and the hammer, are mounted on the key itself.
z is a lever, acting on a hinge or centre, with a spring applied to it at y to
support such lever and the hammer a, b, which bears upon it by means of the
stick or upright d, z, acting on a centre pin at z. The stick d, z, has got on
each side of its top two little plates of brass or any other suitable metal, shaped
at top like a fork, as at d, which little forks embrace the small roller d. The
, roller d is made of leather or any other suitable material, and turns on a
.centre pin fixed inside the opened end of the hammer, the two pieces of brass
supporting the roller leaving a space between them. The sticker passes
between them and touches on the roller also, so that the hammer rests at the
same time on the spring applied to the lever, y, and the head of sticker.
*is a small pin or point of contact, contrived in the hammer for the screw
mounted on the stick to come into contact with it when the fingers depress
the key, so as by bearing heavier than the roller on the spring of the lever y,<,
.to work that spring down, and leave a space between the bottom of the forked
pieces and the sticker v, which sticker, by escaping from under the roller d,
allows the hammer to drop and be supported again by the spring of the
lover y, 2.
C is a spring applied to the sticker v to throw it back under the
roller d. The check or apparatus to prevent the hammer rebounding to the
wire is entirely new, and acts as follows:-, e, is a lever, mounted on its
centref upon the key itself. g, g, is a wire, screwed into the key frame, and
passing freely through a groove or opening cut in the key. On the top of
this wire is mounted at 9, on a centre or pivot, a lever h, h, attached to the
lever e, e, by a rod or wire i, i, with a right-hand screw at one end, and a left-

page_text: hand screw at the other for adjustment. The combination of this contrivance
is such that when the centre f on the key is raised, the lever e, e, falls towards
the hammer, so as to come in contact with the part t when it has struck the
wire. Meanwhile the point or screw le comes in contact with the point / to
effect the escapement of the sticker from under the roller d. To the
lever e, e, is attached on a hinge or centre m, a piece m, n, kept apart from
the lever e, e, by a spring o, regulated to a proper distance by the tapped or
adjusting stop wire p. The piece m, n, bears on the lower extremity of the
lever q, r, moving on its centre W, carrying the damper a, which is raised up
from the string, and allows it to vibrate by a spring &, when the lever e, c,
carries back with it the piece m, n.
Sheet III. represents the application of my new system of action to the
horizontal grand or square pianoforte, with the hammer striking above the
string in the direction towards the sounding board (as in cabinet pianofortes).
Fig. 7 represents the action at rest, and Fig. 8 when the key is held down
after the blow of the hammer to the wire; in both Figures the same letters
denote the same parts. a, a, is a rail going from one end of the instrument to
the other to support the hammers and other pieces of the action, to which rail
they are attached so as to allow the whole of the action to be removed in one
frame; it is obvious that such frame is to be attached to both ends of the caso
in a suitable manner, and kept firm and prevented from warping or casting by
means of metal pillars or wires going in the spaces between the strings through
holes in the sounding board, and screwing into some solid rail underneath.
b, c, is the hammer moving on its centre at 6, kept from falling on the wire by
the spring d, which application of such spring I do not give as new.
o, f, is
an intermediate lever between the key and the hammer; the centre is at e; on
this lever is mounted on a centre at g, the lever h, supporting, with the spring n
applied to it, the hammer by means of the stick i, and the metal forked pieces
aforesaid described, embracing the roller. k is the sticker bearing on the roller
also between the two forked metal pieces; the stick i has a screw to come in
contact with the point l. m is the point of contact which makes the sticker k
escape from under the roller when the key is depressed by the finger; the
stickerk is thrown back under the roller by the spring n, fixed on the centre g.
The operation performed by this apparatus is the same in effect as that per-
formed and described in Fig. 4, with the only difference that such operation is
performed on the other side of the centre of the hammer. The opened end
of the hammer being in this position or application of mechanism on the
other side of the centre of the hammer, it is evident that the different pieccs
act against the power or resistance of the spring d, keeping the hammer from

page_text: the string, instead of acting on the weight or momentum of the hammer as
usual. The motion of the key is communicated to the whole apparatus by
'means of a rod or sticker w, passing through guides o, o, and the sticker is so
shaped as to rest on the lower guide when the set of keys or a separato key is
withdrawn from the instrument; with such arrangement of mechanism I
apply a case constructed on the plan of the cabinet pianofortes in general,
where the sounding board extends without interruption from the wrest pin
plank to the other end of the case, as shewn at E, E, E.
Sheet IV., Fig. 9 and 10 represent an application of my new system of
action to the upright pianofortes. The key a, b, c, in both Figures, is made of
an angular or elbow shape, instead of being straight, and the different parts of
the mechanism are mounted on the elbow part of it b, c. It is obvious that
such action may be placed at any distance above or under the level of the keys,
so as the form or construction of the instrument may require, by means of a
striker between the key a, b, and the elbow part of it b, c, by detaching the
part a, b, of the key from the elbow part of the key b, c, which then will answer
as an intermediate lever, and placing it with the hammer and mechanism upon
it, to any desired point on the wires, the motion of the key a, b, would be
then communicated to this intermediate lever by the well known contrivance
of a light wooden rod, striker, or riser. d, Figure 9, is a piece of wood screwed
fast on the elbow part of the key b, c. e is the lever supported by the
spring f, which lever and spring support the hammer by means of the roller i.
is the sticker bearing, also under the roller. Z is the point of contact
to make the sticker escape from under the roller; m is the piece of flat wire
to be bent more or less for regulating, and which, following the motion of the
elbow part of the key, is brought towards the head of the hammer and checks
it at n after the blow, and prevents the hammer rebounding to the wires. o is
the point of contact brought about nearer the centre of the hammer to prepare
the escapement.
Fig. 10 contains a new contrivance for the check, which is of importance;
the lever or check d, e, f, which receives the hammer in its fall after striking
the wire, instead of being a fixture on the intermediate lever or the key is
moveable upon a centre at e, and thrown forward to check the hammer from
the circumstance of its resting at f on the escaping lever g, which, being
stopped in its motion at h, acts upon the end of the lever f, e, and encreases the
motion of the check at d. The advantage of this new check is obvious, and
though it is here given in the action of an upright pianoforte, it may be
applied to any other arrangement of the same principle for any kind of piano-
fortes; in fact, by merely lengthening the part b, c, in Fig. 9 and 10, both

page_text: i
arrangements of mechanism would nearly answer for horizontal pianofortes,
especially for the square. is the damper placed in the space between the
strings and the sounding board, moving on its centre at k by means of the rod
or wire acting upon it when the key is depressed; m is the spring to make it
press upon the wire more or less, so as to damp sufficiently the vibration.
In witness whereof, I, the said Pierre Erard, have hereunto set my hand
and seal, this Fifth day of July, in the year of our Lord One thousand
eight hundred and twenty-five