IMPROVEMENTS IN PIANOFORTES
Year: 1877

page_text: LETTERS PATENT to Julius Cossel, of 11, Queen Victoria Street, in the City of
London, for the Invention of "IMPROVEMENTS IN PIANOFORTES." A com-
munication from abroad by Carl Heinrich Ludwig Plass, of Hamburg, in the
Empire of Germany.
Sealed the 22nd January 1878, and dated the 6th November 1877.
PROVISIONAL SPECIFICATION left by the said Julius Cossel at the Office of
the Commissioners of Patents on the 6th November 1877.
JULIUS COSSEL, of 11, Queen Victoria Street, in the City of London.
"IMPROVE
MENTS IN PIANOFORTES." (A communication from abroad by Carl Heinrich Ludwig
Plass, of Hamburg, in the Empire of Germany.)
This Invention relates to improvements in pianofortes, and consists in fitting near
or at the tail end of the hammer stem a nut through which a screw pin is passed,
said screw pin carrying or having attached for adjustable pressure purposes a helical
spring to bear upon the top end of the hopper stick.
The tension of the spring is such that the hammer head is kept supported by
the spring within an easy distance of the string ready for a repeat of the blow should
it be necessary.
The tail end of the hammer is hung or suspended from the hammer rail, and has
a leather or other buffer for the nose of the hopper stick to lift the hammer by.
Instead of the nut, the screw pin may be passed through the tail end.
The Invention is described as it would be when applied to a "grand," but it can
be adapted for all kinds of pianos.
"
In an upright" for instance, the pin through the "butt" of the hammer is pressed
upon by the helical spring whose upper end is fixed to a projection on the "butt"
or tail piece. In this "upright" action, the hopper stick is jointed to a stud on
a horizontal piece; the back end of which carries a rod for operating the damper
by an upward circular movement through its connection with, a link from the
[Price fidi

page_text: damper rail, the damper pad or cushion being thus brought to act upon the string
to damp it at about the spot at which it had previously been struck by the hammer.
The horizontal piece is connected to the ordinary "jack" which is acted upon by
the key.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Julius Cossel in the Great Seal Patent Office on the 4th May
1878.
JULIUS COSSEL, of 11, Queen Victoria Street, in the City of London. "IMPROVE-
MENTS IN PIANOFORTES." A communication from abroad by Carl Heinrich Ludwig
Plass, of Hamburg, in the Empire of Germany.
:
This Invention relates to improvements in the working parts of pianofortes, and
consists,-
First. In fitting in the tail end or butt of the hammer stem a nut through which
a screw pin is passed, said screw, pin carrying for adjustable lift purposes a helical
or a spiral spring to bear upon the top end of the hopper stick.
Secondly. In fitting in a projection in the back of the hammer rest a screw.
pin, whose lower end has a pad or leather buffer to regulate the movement of the
back part of the key.
The improvements herein-before referred to are clearly shown in the accom-
panying Drawings, in which Figure 1 represents a complete action as fitted to a
horizontal instrument.
at a.
A is the key; B, the pivot or pin on which it moves when pressed upon by the
finger of an operator; C, is the jack to which the hopper stick D is hinged or jointed
This hopper stick has a tail piece b, between which and a projection c of the
jack a helical or spiral spring d is fitted, to force the nose e of the hopper stick into
the notch h under the butt or tail piece F of the hammer G each time the hammer
falls after striking its string or wire H.
The tail piece F of the hammer is hung or pivotted to the rail I in the usual
manner, but it has within the body of it a screw nut J through which a'screw pin K
passes; the lower end of this pin has attached a helical or a spiral spring f, whose
opposite end being fitted with a leather pad, bears in a recess formed in the top of
the hopper. This screw pin and spring form an important portion of this Invention
as by their combination in connection with the hopper, which has to execute a short
movement only, blows of the hammer on the string or wire are produced most
powerful or very soft, and with almost unlimited quickness, when and depending
upon the manner in which the key is acted upon. By turning the screw pin K more
or less, the desired strength can be easily given to the spring, which is of very great
advantage, especially should the spring become weak by heavy or long use.
The same amount and volumn of sound as above-mentioned is by the action of
the spring produced when the key A, having been pressed down completely, is lifted
a short distance only, and acted upon again, leaving nothing to be desired as regards
clearness of sound.

page_text: To a projection i at the back of the hammer rest L, a screw pin g is passed, its
lower end has a pad or buffer j upon it to receive the back part of the key when
acted upon. By turning this screw pin more or less, the movements which the key
has,to execute are regulated with the utmost ease and certainty.
In the front projection k of the hammer rest L, a screw pin is passed, whose
lower end is fitted with a pad or buffer m to be brought more or less close to the
tail piece 6 of the hopper D, to draw the nose e of the hopper stick out of the
notch h, after having lifted the hammer G, so that in that position the hopper brings
the spring in its full action, and consequently keeps the hammer close to the
spring or wire H. By turning the screw pin K more or less, the hammer can be
held at any suitable distance from the string or wire.
The regulation of the keys so as to adjust them as regards the different weights
of the hammers in the higher and lower octaves, is effected by plugging the front
parts only of the keys with lead; they need not therefore to be plugged in the back
part, because they get the full weight of the hammers, which causes a considerable
fall of the back part of the keys.
The hammer rest L, shown in the Drawing, Figure 1, is only to support the
hammer after the key is removed, which can be done by lifting it off the pin, the
jack C, hopper D, and the sticker N going with it.
°
The damper M is of ordinary construction, and the parts N, O, P, also. It will
be observed by the Drawing, Figure 1, that the working parts of the action move
upon two centres a and n only.
In fitting the Invention to an upright piano, see Figure 2, the screw pin K in the
butt F of the hammer G has attached to it the helical or spiral spring, as explained
for Figure 1.
In this "upright"action, the hopper stick D is jointed to a stud on a horizontal
piece C¹, the front end p of which carries a rod q for operating the damper M by an
upward circular movement through its connection with links R, S, from the
damper rail T, the damper pad or cushion being thus brought to act upon the
string H to damp it at about the spot at which it had previously been struck
by the hammer G. The horizontal piece C¹ rests upon the jack C, and is
acted upon by the key A.
By hanging the damper M in the manner described and shown, the vibrations of
a string are stopped with greater certainty and with more uniformity.
Having now described the nature of the said Invention, I declare that I claim,-
First. The improvements in the actions of pianofortes herein-before set forth, and
substantially as shown in the annexed Drawings.
Secondly. I claim fitting and using an adjustable screw pin K in the "butt" or
tail end F of a piano hammer in combination with a helical or like spring f, bearing
upon the hopper stick in the manner and for the purposes described, and substantially
as shown in the accompanying Drawings.
In witness whereof, I, the said Julius Cossel, have hereunto set my hand and
seal, this Fourth day of May, in the year of our Lord One thousand
eight hundred and seventy-eight.
JULIUS COSSEL. (L.S.)