IMPROVEMENTS IN PIANOFORTE ACTIONS
Year: 1878

page_text: LETTERS PATENT to Henry William Hemsworth, of Southend, in the County
of Essex, Gentleman, for the Invention of "IMPROVEMENTS IN PIANOFORTE
ACTIONS." A communication from abroad by Hermann Alm, of Brandenburg,
in the Empire of Germanv.
Sealed the 12th November 1878, and dated the 1st August 1878.
PROVISIONAL SPECIFICATION left by the said Henry William Hemsworth
66
at the Office of the Commissioners of Patents on the 1st August 1878.
HENRY WILLIAM HEMSWORTH, of Southend, in the County of Essex, Gentleman.
IMPROVEMENTS IN PIANOFORTE ACTIONS." [A communication from abroad by
Hermann Alm, of Brandenburg, in the Empire of Germany.]
This Invention has for its object improvements in pianoforte actions, and relates
to an improved repetition movement therefor, whereby far greater volume and
richness of tone is obtained than has hitherto been practicable at a comparatively
nominal additional cost.
Such Invention consists of a suitable spring rod arranged so as to work freely in
the stump of the hammer butt, the upper part whereof is prolonged so as to extend
as far as the little check. Such spring rod is actuated by a small fine spiral spring
placed betwixt the end thereof and a suitable block fitted to the stump of the
haminer butt; and the same is furnished with a suitable head with which the
hopper comes in contact after escaping from the notch in the hammer butt. By
this means the hammer is kept in juxtaposition with the string as long as the key
in connection with such hammer is manipulated, and a greatly improved repetition
is obtained, as when the key commences to rise the hopper is ready to instantane-
ously spring back into the notch in the hammer butt and cause the blow of the
hammer to be repeated, while the damper is suspended from parallel links instead
of being mounted to rock on a centre in the ordinary manner.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry William Hemsworth in the Great Seal Patent Office on the
31st January 1879.
HENRY WILLIAM HEMSWORTH, of Southend, in the County of Essex, Gentleman.
"IMPROVEMENTS IN PIANOFORTE ACTIONS." A communication from abroad by
Hermann Alm, of Brandenburg, in the Empire of Germany.
This Invention has for its object improvements in pianoforte actions, and relates
to an improved repetition movement therefor, whereby far greater volume and
richness of tone is obtained than has hitherto been practicable at a comparatively
nominal additional cost.
Such Invention consists of a suitable spring rod arranged so as to work freely in
the stump of the hammer butt, the upper part whereof is prolonged so as to extend
as far as the little check. Such spring rod is actuated by a small fine spiral spring
placed betwixt the end thereof and a suitable block fitted to the stump of the
hammer butt; and the same is furnished with a suitable head with which the
hopper comes in contact after escaping from the notch in the hammer butt. By
this means the hammer is kept in juxtaposition with the string as long as the key
in connection with such hammer is manipulated, and a greatly improved repetition
is obtained, as when the key commences to rise the hopper is ready to instantane-
ously spring back into the notch in the hammer butt and cause the blow of the
hammer to be repeated, while the damper is suspended from parallel links instead
of being mounted to rock on a centre in the ordinary manner.
And in order that my said Invention may be better understood and readily
carried into effect, I will now, with the aid of the accompanying Drawing, proceed
more particularly to describe and ascertain the same.
:-
The accompanying Drawing represents the usual mechanism of a piano with my
improved repetition action adapted thereto, and which action is constructed as
follows The upper part of the hammer butt (4) above the jack (2) is prolonged,
such prolonged piece (a) extending as far as the little check (6), whereas in the
ordinary mechanism the butt and the little check (6) are connected by a short rod
called the little check rod. The little check is surmounted by an angle or square (b),
between which and the prolongation (a) a fine spiral spring (c) is introduced. A
hole is bored straight down through the prolonged portion (a) of the butt beneath
the spring in which a sticker (d) works, the lower end of which sticker terminates
in a wad (e) which rests upon the jack. The upper end of this sticker is in
connection with the spring (c), so that the latter, by means of the sticker (d) and
the wad (e), presses upon the jack (2).
I will now proceed to describe the operation of my Invention, which is as
follows: In the case of an ordinary action when the key is struck and held down
the jack (2) releases itself from the notch (3) of the hammer butt (4), and cannot
therefore exercise any further action upon the hammer (5), and in order to again
set such hammer in motion the jack must fall again into the notch of the butt. To
effect this the jack must be depressed, which depression takes place when the key is
allowed to rise; but it is not until the key has regained its normal level that the
jack again falls into the notch. This will be evident if the depressed key only be
allowed to rise slowly. If the key, however, be struck again before it has returned
to its normal level it is not possible for the jack to exercise any impetus upon the
hammer, and therefore no repetition of the sound is produced.
•
These various disadvantages are obviated in the following manner by my
improved repetition action :—Upon the key being struck the jack releases itself
from the notch in the manner already described. It is not, however, necessary for
the key to regain its normal position in order to cause the jack to again fall into
the notch. On the contrary, the upward movement of the key may be interrupted
at any stage by a fresh stroke, while the jack will always remain in the notch and
exercise an impetus upon the hammer, thus producing an equally powerful sound
each time the key is struck.

page_text: If desired, the key may even be permanently prevented from re-assuming its
normal position by means of a hook or its equivalent placed in any suitable position,
and if this be done the key may then be repeatedly struck with the utmost rapidity,
the hammer completely falling back each time on to the ruler or stay at the back
thereof; and supposing the number of repetitions to amount to 1,000 per minute
the sound will never fail, but will always ring out clearly and distinctly, whereas
in the ordinary action if the key be struck with similar rapidity no sound will be
produced, not even if the key is left perfectly free in its action. It is true such
rapidity of repetition is not called for in playing, but this example serves to shew
the immense improvement effected by my improved repetition action over those of
ordinary construction.
-
My improved repetition action, as illustrated in the Drawing, produces the results
above described by the jack itself after being released, arresting the hammer in its
fall (which in the ordinary action is done by the check), and by the jack on the
key rising again, only allowing the hammer to fall in the same ratio as the jack
itself falls, while the latter, when falling, is pressed into the notch of the butt.
This is effected in the following manner: The jack on being released from the
notch presses on the wad (e), and thereby by means of the sticker (d) sustains the
butt by the upper portion or prolongation (a) as the pressure of the key which
raises the jack is stronger than the pressure of the spring (c) which depresses the
sticker, while the hammer which is attached to the butt is sustained together with
the butt in the manner already described. On the pressure being withdrawn from
the key and the consequent falling of the jack the spring (c) comes into action, and
by means of the sticker (d) and the wad (e) presses the jack at once into the notch,
thus enabling the jack at any stage of the upward movement of the key on the
latter being again pressed down to instantaneously give a fresh impulse to the
hammer.
One of the most important features of my Invention consists in the falling back
of the hammer, and the downward movement of the jack being regulated in such
a way as to correspond with one another.
I prefer also to suspend the damper by means of parallel links, as shewn in the
Drawing, instead of being mounted to work on a centre in the ordinary manner,
but I make no claim for the use of such parallel links, as the same only facilitate
without being indispensable to the working of my Invention.
Having thus particularly described and ascertained the nature of my said Inven-
tion, and the manner of carrying the same into effect, I would have it understood
that what I claim as novel is the manufacture and use of an improved repetition
pianoforte action, wherein I dispense with the little check rod by prolonging the
hammer butt in combination with the angle or square (b), the spiral spring (c), the
sticker (d), and the wad (e), all substantially in the manner and for the purposes
herein-before described and illustrated.
In witness whereof, I, the said Henry William Hemsworth, have hereunto set
my hand and seal, this Thirtieth day of January, in the year of our Lord
One thousand sight hundred and seventy-nine
Witness,
ELT & Co.,
British and Foreign Patent Office,
33, Southampton Buildings,
Holborn,
London,
W.C
H. W. HEMSWORTH. (L.S.)