PIANOFORTE ACTIONS FOR UPRIGHT PIANOS
Year: 1888

page_text: Date of Application, 10th July, 1888
Specification Accepted, 31st Aug., 1888
I, NEWNHAM BROWNE, of 73 Cheapside in the City of London, Fellow of the
Institute of Patent Agents do hereby declare the nature of the said invention for
"PIANOFORTE ACTIONS FOR UPRIGHT PIANOS" which invention has been communi-
cated to nie from abroad by Charles Bunce and Edwin H. Benedict both of No. 56,
Court Street in the City of Brooklyn, County of Kings, and State of New York,
United States of America, Piano Manufacturers, to. be as follows:-
--
This invention relates to certain improvements in the construction of piano forte
actions for upright pianos whereby it is rendered possible to repeat the blow of the
hammer against the string at any position that the key may be in. To this end a
peculiar construction of hammer is adopted, having a hammer butt which is made
substantially circular or are like in outline said circular portion resting directly upon
the transmitter which is itself rigidly fixed with relation to the part to which it is
attached, and which is, as contemplated by this invention, either the rear portion of
the key itself, or a part fixed thereto.
The invention further includes a peculiar novel construction of the rail to which the
hammer butts are pivoted, and of the damper rail to which the damper levers are
pivoted, whereby the cost of making the pianos is materially cheapened. And the
invention further includes the method of making the hammers and dampers.
The invention is illustrated in the accompanying drawings, in which Fig. 1, is a
vertical section of an upright piano forte action, showing the same at rest. Fig. 2, is
a similar section showing the hammer raised to the string. Fig. 3, is a perspective
view of one end of the hammer butt rail. Fig. 4, is a detailed sectional view showing
a modification of the transmitter between the key and hammer butt.
In the drawings A, is the bottom rail of the key frame; B, is one of the keys;
C, is the usual center rail to which the keys are pivotally connected; D, is the front
rail of the key frame; and E, is the back rail which is hinged at a, to the bottom rail.
All of these parts are of ordinary and well known construction and require no further
description.
F, is the hammer butt rail to which the hammer butts are pivoted and which is
secured to the bottom rail immediately behind the keys. This rail is made of a single

page_text: piece of wood which serves as the bearing rail for all of the hammer butts used in the
piano, as long as the piano does not contain more than four or five octaves. The
bearings for the several hammer butts are formed in this rail in the following
manner A groove is made on the top edge of the rail in which is placed a wire
rod G, extending the whole length of the rail. Then a second strip of wood is glued
on to the rail above the wire. When the glue is dry the wire is drawn out thus leaving
a hole extending the entire length of the rail. The rail thus formed is then sawed out
so that a series of notches b, b, are formed on its upper side throughout its entire
length, the notches being of the proper width and depth to receive the hammer butts.
The hammer butts which are provided with suitably bushed apertures are then inserted
into the notches and pivoted therein by means of the wire G, which is inserted through
the hole in the rail and through the bushed apertures of the hammer butts. In this
manner the hammer butts are pivoted in a very economical as well as efficient
manner.
H, is one of the hammer butts which has secured thereto an upwardly extending
shank I, which carries on its upper end the hammer head J, which is adapted to strike
one of the strings L. The hammer butt has its lower edge or surface formed in a
curved line which is substantially circular or are like. In the preferred construction
of the action this circular edge of the hammer butt rests directly upon the rear end of
the key which constitutes itself the transmitter between the key and the hammer butt.
It will be observed that with this construction the transmitting or rear end of the key
will always be in contact with some portion of the circular edge of the hammer butt
in whatever position the key may be held so that at all times by further depression of
the key the hammer may be thrown back to strike the string.
M, is one of the damper levers which is pivoted in a damper rail, N, between the
hammers and the strings. The damper levers carry on their upper ends the damper
cushions, which are normally held in contact with the strings by means of small
springs c, mounted upon the damper rail. A single damper rail is used for all of the
damper levers and it is constructed in exactly the same manner as the hammer butt
rail, and the damper levers are pivoted therein in the same manner that the hammer
butts are pivoted in the hammer butt rail.
The hammer shanks are supported in their position of rest by a hammer shank rail O,
which is suitably mounted in the piano frame. Each hammer shank carries a regulating
screw P, having a padded end e, which, when the hammer is thrown back to strike the
string, comes in contact with the lower end of the damper lever thus swinging the
damper pad away from the string and permitting the free vibration of the latter.
When the hammer falls backs to its position of rest, the damper lever is released
and the damper pad is again pressed against the string by means of its spring c.
When the improvements are used with pianos embracing more than four or five
octaves wherein a larger number of strings are employed it is necessary to place some
of the hammer butts at such a distance above the keys that the keys cannot act
directly upon the circular edge of the hammer butts. In such a case an additional
transmitting device must be interposed between the key and hammer butt as is shown
in Fig. 4. This transmitter which is rigidly attached to the rear end of the key
consists of a vertical tracker Q, which has rigidly secured to its upper end a horizontal
cross-piece R, which comes directly in contact with the curved edge of the hammer
butt and takes the place of the transmitting rear end of the key in the construction
shown in Figs. 1 and 2. In whichever construction that is employed it will be
observed that there is no independently moving part interposed between the key and
the hammer butt, but that the transmitter is in any case rigidly fixed with relation to
the part to which it is attached.
In constructing the hammer butts, hammer shanks and hammer heads, these parts
are made from separate sheets each wide enough to contain one or more full sets for a
piano. The sheets from which the hammer butts and hammer heads are formed, are
grooved to admit the edges of the sheet from which the hammer shanks are formed.
The hammer heads are covered with felt or leather while still in the sheet, and the
hammer shank sheet is then glued to the hammer head and hammer butt sheets thereby

page_text: making one or more complete sets of hammers while still in the sheet, and then the
sheets are sawed apart to form the individual hammers. The damper levers and
damper heads are made in the same manner.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
'
1. In a piano forte action the combination of a key, a simple transmitter rigidly
fixed with relation to the part to which it is attached, and a pivoted hammer butt made
substantially circular or arc like in outline.
a
2. In an upright piano forte action a pivoted hammer having a hammer butt with
its lower edge substantially circular in outline, in combination with a key having
transmitting part in substantially a horizontal plane on its rear end, the curved edge
of the hammer butt resting directly upon said transmitting part in which ever position
the key may be held at rest, substantially as set forth.
3. In a piano forte action, the strings, the damper rails, the damper levers pivoted
in said damper rail and having damper pads adapted to said strings, in combination
with the keys of the piano, the hammer butt rail behind the rear ends of the keys,
the hammers pivoted in said hammer rail having hammer butts and hammer heads,
and being also provided with regulating screws, carrying pads which co-operate with
said damper levers, and said hammer butts having one edge substantially circular in
outline, said curved edge being acted upon by a horizontal transmitting surface rigidly
attached to the key, substantially as set forth.
4. The method of making the rails for the hammers and dampers of a piano forte
action of the whole length of the action in two pieces, which consists in grooving tho
top edge of each rail along its whole length to receive a wire, then gluing a strip of
wood on the top of the rail above said wire; and when the glue is dry drawing out
the wire, whereby a hole is formed in the entire length of the rail, and then forming
notches in said rail, substantially as set forth.
5. A rail for the hammers and dampers of a piano forte action, having a strip of
wood glued along one end or side thereof, said end or side being first grooved and
said rail with the glued strip attached thereto being formed with notches for the
reception of the hammers or damper levers, substantially as set forth.
6. The method of making the hammers of a piano forte action, which consists in
first securing together the sheets of wood from which the hammer heads, shanks and
butts are formed, and then cutting out from such united sheets the hammers in a
completed condition, substantially as set forth.