Improved Repeating Mechanism for Pianofortes and the like.
Year: 1893

page_text: Date of Application, 14th June, 1893-Accepted, 22nd July, 1893
COMPLETE SPECIFICATION.
Improved Repeating Mechanism for Pianofortes and the like.
I, HEINRICH MAURER, Manufacturer of 11 Friedrichs Platz, Carlsruhe, in the
Grand Duchy of Baden, German Empire, do hereby declare the nature of my
invention and in what manner the same is performed to be particularly described
in and by the following Specification :-
:-
The object of the present invention is to construct the jack or escapement lever
of pianofortes in such manner as to obtain a more perfect repetition than has
hitherto been the case.
The reason why almost all repetition mechanisms and devices have hitherto
proved to be more or less inadequate, is that they do not enable the jack to get
back into position underneath the hammer block, before the hammer has fallen
back into its position of rest, after the key has been released. In order to provide
a device which shall insure perfect repetition, it is absolutely necessary that the
jack be caused to fall into position underneath the hammer (ready for the next
blow) before the hammer has fallen back into its position of rest.
I have attained this object by means of my invention, which consists in providing
the jack near its top, with a pivoted spring lever, adjusted by means of a stop, to
project underneath the hammer block, but not to be contact with the same when.
the jack is in position thereunder. This lever operates to retain the hammer by
catching underneath the block just at the moment when the same is falling back
after the jack has been disengaged therefrom, and thus preventing the hammer
from regaining its position of rest, before the said jack has come into position
underneath the hammer block.
In order to make this Specification more easily intelligible, reference is had to-
the accompanying drawings forming part of the same and in which similar letters
of reference denote similar parts throughout the several views.
Fig. 1 is a side elevation showing my improvement in connection with a pianoforte
mechanism.
Fig. 2 is a similar part elevation showing a modified form of carrying out my
invention.
The jack is provided with a pivoted lever at its upper end, having its longer.
arm projecting under the block a¹ of the hammer a, and being held against its.
adjustable stop or set screw e by means of the jack spring fattached to the shorter
end of the said lever c by a band. The hook d serves to limit the movement of the
lever c in the opposite direction and simultaneously obviates the necessity of the
protecting batten hitherto employed.
The device operates in the following manner :-
When the jack 6 has been disengaged from under the hammer block a¹ and the
hammer is about to fall back into its position of rest, the lever c catches underneath
the said hammer block and detains it until the jack has had time to regain its
proper position underneath said block. As soon as this has taken place the lever c
ceases to be in contact with the block a¹.
In the modification shown in Fig. 2, the hook d is dispensed with and the lever c
is not actuated by the jack spring, but by an independent spring f', whilst the jack.
is provided with a spring g arranged underneath its rearwardly projecting arm.
The operation of this device is substantially the same as described with reference-
to Fig. 1 and I have found this latter arrangement to be simpler and more efficient.
in the practice.
It will be observed that the advantage of my present invention is that it can.
easily be applied to all pianos at present in use without causing much extra
expense.

page_text: Having now particularly described and ascertained the nature of my said inven-
on, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In pianofortes a spring mechanism in connection with the jack lever arranged
to contact with the hammer block and retard its fall substantially as described.
2. The combination with a jack 6 of a spring lever, pivotally attached thereto
and having its arm projecting underneath the hammer block, and suitable stops for
said lever substantially as described and for the purpose specified.
3. The combination of the jack b, having spring 9 underneath its rearwardly
projecting arm and the lever e pivotted to said jack and having spring 1 and stop e
and arm to project underneath the hammer block, substantially as described and for
the purpose specified.
Dated this 14th day of June 1893.
REGINALD W. BARKER,
Applicant's Agent.