An Improvement in Piano-forte Actions.
Year: 1892

page_text: COMPLETE SPECIFICATION.
An Improvement in Piano-forte Actions.
I CHARLES GEHRLING of 59 Rue de l'Ourcq, 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 an improvement in pianoforte actions. The said
improvement is particularly applicable to actions known as sticker check actions
and founded upon the "Molyneux" type of action, which actions are familiar to
those who are skilled in the manufacture of piano-fortes.
The object of my said invention is to provide an improved set-off in actions
of a similar type to the aforesaid, so as to reduce the friction of the action, to
give the hammer greater freedom than has been possible on actions of that type
as hitherto constructed, to facilitate repetition, and to enable the hammer to
deliver a more powerful blow. Moreover in the improved action constructed
according to my invention, the regulation is considerably facilitated.
In order that my said invention may be readily understood I will now proceed to
describe the same with reference to the accompanying drawings, in which
Figure 1 illustrates in side elevation an action to which my said improvement is
applied.
Figure 2 is a view similar to Figure 1, but with the movable parts of the action
in the positions they assume when the outer end of the key is depressed.
Like letters of reference indicate corresponding parts in all the figures.
A is the hammer rail, B is the hammer, C is the sticker rail, D is the sticker,
E is an arm by which the movement of the lower end of the sticker is guided, the
upper end being guided by the pin 6 fastened in the lower end of the butt of the
hammer as shown. F is the key.
G is the set-off rail, placed at the front side of the action as shown and H is a
set-off secured therein, the stem of the set-off being screw threaded to enable it to
be readily adjusted in the set off rail.
D' is a set-off arm, secured to the sticker so as to engage with the button of the
set-off when the said sticker is raised by the key F.
The operation of this action will now be described.
Let it be assumed that the parts of the action are in the positions indicated
in Figure 1. If now the key F be depressed, its inner end, in the first portion
of its movement will raise the sticker D until the arm D' is brought into contact
with the button of the set-off H. During the second part of the movement
the key, acting upon the lower end of the sticker continues to raise it while the
arm D is retained by the set-off and consequently the sticker is tilted into the
position indicated in Figure 2 so as to cause its head to move clear of the lower
end of the hammer in the customary manner. By turning the set off the screw
thread on its stem will cause its button to move down or up so that the tilting
of the sticker may commence sooner or later as may be desired.
It is obvious that in the improved action hereinbefore described the operation of
setting off is performed more sharply and with less friction than in actions where
an inclined surface is employed to actuate the set-off.
Although I have herein shown only one mode of carrying my said invention into
effect, I do not desire to confine myself to that particular method, which is given
by way of example. Obviously I may modify the said apparatus without departing
from the nature of my said invention.

page_text: Having now particularly described and ascertained the nature of this inven
tion and in what manner the same is to be performed, I declare that what I
claim is
In pianoforte actions of the kind hereinbefore referred to the combination with
a sticker having an arm or projection rigidly secured to the front thereof, of a·
set-off substantially as hereinbefore described for the purposes specified.
Dated this 20th day of April 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.