IMPROVEMENTS IN PLANOFORTE ACTIONS
Year: 1887

page_text: 1. FRANZ PETERMANN, of No. 43 Dresdener Strasse in the City of Berlin, Prussia,
Germany, Pianoforte Manufacturer, do hereby declare the nature of my Invention for
"IMPROVEMENTS IN PLANOFORTE ACTIONS" 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 improvements in pianoforte actions generally known
under the name of repeating actions and more especially to a device for catching the
hammer when it rebounds after striking the wire or string, said device being extremely
simple & easy to manufacture and readily adjustable.
In employing my invention I do away with a great part of the mechanisms now in
use such as catch, counter catch, loops and bands, the latter of which are exposed to
the many destructive influences of the climate etc in the tropics.
The hammer is prevented from coming into contact with the wire or string a second
time after the key has been struck by means of an inclined surface formed on the
hopper and against which the puppets which generally serve only for releasing the
paris operate so as to carry out two functions.
Figure 1 is the elevation of a pianoforte action before the key is touched and
Figure 2 a like elevation after the key has been struck and before the finger has left
the key.
a is the hammer, the jack or hopper which is connected to the hammer and is
provided with an inclined surface b¹.
e is the releasing lever with projection c¹, and adjustable puppet d which abuts
against the incline.
A second adjustable puppet d', arranged in the jack or hopper blies against an
inclined surface of the hammer rail e and operates in opposite directions to the
puppet d. The hammer is arrested in the following manner :-When the key is
depressed the hammer a is raised by means of the releasing lever c and jack or
hopper and causes the hammer to strike the wire string.
During this time the puppet d presses the hopper from the projecting ledge c¹,
and lays itself against the incline ¹, when the hammer a falls back. This causes the

page_text: second puppet d', to be pressed firmly against the hammer rail e and so to catch the
hammer a.
The greater the pressure which is exerted on the key the firmer will the jack or
hopper, he arrested by the puppets d d', and thus all second contact with the wire
or string be avoided. When the pressure is removed a spring will bring all the parts
back to their original position.
Figure 3 represents a modification of the action shown in Figures 1 and 2.
If a third puppet (Figure 3) is employed the movement of the hammer can be
easily regulated and if the felt cover is worn can be screwed up so as to attain an
exact movement of the rocking lever.
In the modification shown in Figure 3 a third puppet d² is applied to the jack or
hopper and abutts against an inclined surface c² of the rocking lever c. The object
of this third puppet is to attain a regulation of the hammer recoil and a ready
adjustment of the movement of the hammer and rocking lever.
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. The construction arrangement and employment of a jack or hopper with
inclined surface the object of which is to catch the hammer after it has struck the
wire or string by means of the puppet d of the releasing lever e and the puppet d², in
the jack or hammer, substantially as described and shown.
2. The application and arrangement of a third puppet 2 in the jack or hopper said
puppet operating against the incline of the rocking levere (Figure 3) alone or in
combination with the device claimed in claim 1, substantially as described and shown.
Dated this 14th day of Fahmam: 1887