Improvements in Grand Pianoforte Actions.
Year: 1894

page_text: Date of Application, 5th Feb., 1894
Complete Specification Left, 5th Nov., 1894-Accepted, 8th Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Grand Pianoforte Actions.
I, JOSEPH HERRBURGER, of 16, Rue de l'Evangile, Paris, in the Republic of
France, Pianoforte Action Manufacturer, do hereby declare the nature of this
invention to be as follows:-
My invention relates to the actions of grand pianofortes, and it consists-
Firstly in replacing the spring usually employed in existing actions of the Erard
type, which spring was fixed on the fork of the lever and which consequently was
not adjustable and occasioned friction by another spring fixed to the lever itself.
The lower end of this spring acts directly on the jack whilst the upper end acts
without friction on the lever as this spring is fixed above. Owing to the position
it occupies it becomes easy to regulate it by means of a screw passing through the
lever and the lower end of which bears on the tail of the spring.
Secondly in diminishing the friction of the hammer on the lever by adapting on
the said lever a longitudinal piece or double lever jointed to a projection on the
lever, which double lever in its turn carries a projection provided with a pad acting
on the stem of the hammer.
In this case the regulating screw is sufficiently long to pass through the lever
and double lever in order to be accessible.
Dated this 5th day of February 1894.
G. F. REDFERN & Co.,
, South Street, Finsbury, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Grand Planoforte Actions.
I, JOSEPH HERRBURGER, of 16, Rue de l'Evangile, Paris, in the Republic of
France, Pianoforte Action Manufacturer, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement : —
My invention relates to the action of grand pianofortes and is illustrated in the
accompanying drawings, in which :-
Figure 1 is a side elevation of a grand pianoforte action of the Erard type of
the kind most generally employed:
Figures 2 and 3 are similar views shewing my improvements applied thereto :
Figures 4 and 5 are respectively a side elevation and a plan of the underside of
one part of the mechanism; and,
Figures 6 and 7 are respectively a side elevation and a rear elevation of another
part of the mechanism.
In the action usually employed and illustrated in Figure 1, the spring R being
fixed upon the fork F rubs against the lever L, and moreover is not adjustable.
According to my invention 1 replace the said spring by the form of spring R
shewn in Figure 2, which I fix upon a projection on the lever L. This spring, in
which a coil or turn is made, as shewn, to give it greater flexibility, acts with its
lower end upon the jack E and with its upper end upon the lever L, but as it is
fixed to the said lever it only exerts pressure thereon without any friction.
Owing to the position occupied by this lever it becomes easy to regulate it by
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page_text: means of a screw V working in the lever L and bearing on the upper end of the
spring.
Figure 3 represents mechanism similar to that shewn in Figure 2, with another
improvement which I have added thereto. I apply longitudinally above the
lever L an arm L' which I call "a double lever." It is provided at its upper end
At its lower
with a padded projection designed to lift the stem of the hammer.
end it is pivotted at A to a projection S on the lever L. This double lever has
already been adapted by me to the actions of grand pianofortes, but I have
hitherto pivotted it to the fork F. This I have found causes friction by reason
of the displacement of the double lever with relation to the lever L during
movement; whereas by pivotting the double lever to the lever itself all friction is
avoided. In this case the regulating screw V is sufficiently long to pass through
the double lever as well as into the lever L in order to be accessible. Figures 4
and 5 illustrate the manner in which the upper end of the spring is applied to the
lever L, and Figures 6 and 7 shew the recess in the jack in which the lower end of
the spring is inserted.
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. In a grand pianoforte action a spring fixed to the lever itself and rendered
adjustable by means of a screw working in the said lever, substantially as herein-
before described.
2. In a grand pianoforte action, a double lever pivotted to the lever itself instead
of to the fork, substantially as hereinbefore described.
3. In a grand pianoforte action the combination of a spring fixed to the lever
with a double lever pivotted to the said lever instead of to the fork the said spring
being rendered adjustable by means of a screw passing through the double lever
and working in the lever, substantially as hereinbefore described.
4. The improved grand pianoforte actions herein before described and illustrated
respectively in Figures 2 and 3 of the accompanying drawing.
Dated the 5th day of November 1894.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.