IMPROVEMENTS IN AUTOMATIC MUSICAL INSTRUMENTS
Year: 1874

page_text: LETTERS PATENT to Daniel Imhof, of No. 547, Oxford Street, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN
AUTOMATIC MUSICAL INSTRUMENTS."
Sealed the 10th March 1874, and dated the 14th January 1874.
PROVISIONAL SPECIFICATION left by the said Daniel Imhof at the
Office of the Commissioners of Patents, with his Petition, on the
14th January 1874.
I, DANIEL IMHOF, of No. 547, Oxford Street, in the County of
Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN AUTOMATIC MUSICAL INSTRUMENTS," to be as follows:-
:-
My Invention relates to means of damping and sustaining the notes
produced by the strokes of hammers worked automatically by pegs or
projections on a revolving barrel or other travelling surface. For this
purpose I provide the strings, wires, bells, or other sounding objects on
which the hammers strike with dampers of ordinary construction, and I
connect each of those dampers to a lever mounted by the side of the
hammer lever belonging to the same note. On the hammer lever I

page_text: provide a shoulder or projection, which when the hammer is raised by a
travelling peg or projection so as to be ready to strike its note moves the
damper lever so as to raise the damper off the sounding object. The
damper lever is made with a nose or key point like that of the hammer
lever on which the travelling peg or projection acts, and this nose or
key point of the damper lever is arranged in the same line with but a
little behind the nose of the hammer lever. After the travelling peg or
projection has escaped the nose of the hammer lever and thereby allowed
the hammer to strike, it still for a short time holds the nose of the
damper lever and thereby keeps off the damper so as to permit the struck
note to sound until the farther travel of the peg or projection by escaping
the damper lever allows the damper to drop and stop the sound. The
position and dimension of the nose of the damper lever can be adjusted
so as to keep the damper off for a longer or shorter period after the stroke
of the hammer.
When it is desired to sustain a prolonged note I provide on the barrel
or travelling surface besides the ordinary peg for raising and discharging
the hammer in the same line with the peg an extended projection which
may be in the form of a staple. The peg having raised and discharged
the hammer so as to strike the note, and then having for a short time
sustained the damper, as above described, the extended projection again
raises the hammer before the damper falls, and the shoulder or projection
on the hammer lever when the hammer is thus again raised continues to
sustain the damper during the time occupied by the travel of the
extended projection or staple. The length of this extended projection or
staple is adjusted to the desired duration of the note, and it is made to
terminate with an easy slope so that as it passes from under the nose of
the hammer lever the hammer moves gently towards the sounding object
without again striking at the termination of the period during which the
note is sustained.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Daniel Imhof in the Great Seal Patent Office
on the 7th July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DANIEL
IMHOF, of No. 547, Oxford Street, in the County of Middlesex, send a
greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of January, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Daniel Imhof, Her special license
that I, the said Daniel Imhof, my executors, administrators, and
assigns, or such others as I, the said Daniel Imhof, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN AUTOMATIC
MUSICAL INSTRUMENTS," upon the condition (amongst others) that I, the
said Daniel Imhof, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Daniel Imhof, do hereby declare
the nature of the said. Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the accompanying
Sheet of Drawings and to the figures and letters marked thereon, that is
to say:-
My Invention relates to means of damping and sustaining the notes
produced by the strokes of hammers worked automatically by pegs or
projections on a revolving barrel or other travelling surface. For this
purpose I provide the strings, wires, bells, or other sounding objects on
which the hammers strike with dampers of ordinary construction, and I
connect each of those dampers to a lever mounted by the side of the
hammer lever belonging to the same note. On the hammer lever I
provide a shoulder or projection, which when the hammer is raised by a
travelling peg or projection so as to be ready to strike its note moves the
damper lever so as to raise the damper off the sounding object. The
damper lever is made with a nose or key point like that of the hammer
lever on which the travelling peg or projection acts, and this nose or
key point of the damper lever is arranged in the same line with but a

page_text: little behind the nose of the hammer lever. After the travelling peg or
projection has escaped the nose of the hammer lever, and thereby allowed
the hammer to strike, it still for a short time holds the nose of the
damper lever and thereby keeps off the damper so as to permit the struck
note to sound until the farther travel of the peg or projection by escaping
the damper lever allows the damper to drop and stop the sound. The
position and dimensions of the nose of the damper lever can be adjusted
so as to keep the damper off for a longer or shorter period after the
stroke of the hammer.
When it is desired to sustain a prolonged note I provide on the barrel
or travelling surface besides the ordinary peg for raising and discharging
the hammer in the same line with the peg an extended projection which
may may be in the form of a staple. The peg having raised and discharged
the hammer so as to strike the note, and then having for a short time
sustained the damper as above described, the extended projection again
raises the hammer before the damper falls, and the shoulder or projection
on the hammer lever when the hammer is thus again raised continues to
sustain the damper during the time occupied by the travel of the
extended projection or staple. The length of this extended projection or
staple is adjusted to the desired duration of the note, and it is made to
terminate with an easy slope, so that as it passes from under the nose of
the hammer lever the hammer moves gently towards the sounding
object without again striking at the termination of the period during
which the note is sustained.
musical instrument with its hammer and damper worked by pegs on a
revolving barrel, the barrel, sound board, and part of the framing of the
instrument being shewn in section.
Fig. 2 represents a back view of the hammer and damper, the sounding 3
board being supposed to be removed.
B is a portion of the cylindrical barrel which is made to revolve in the
direction of the arrow so that a peg P upon it as it passes under the
inclined nose of the hammer lever H causes the hammer head H¹ to be
withdrawn from the string, and when the peg has passed the nose of the 3
hammer lever a spring S impels the hammer head against the string and

page_text: causes it to sound. So far the construction and operation of the parts
are of ordinary and known kind, and form no part of my Invention.
D is a damper also of ordinary construction mounted and stopped on à
frame F; which frame may be pivotted at fand may be caused to rock
on its pivots so as to withdraw all the dampers from the strings, according
to the mode usually adopted in pianofortes.
The novel construction and arrangement for operating the damper D.
by the movement of the barrel B is as follows:-The damper rod R is.
connected with an adjusting nut to one arm of a bell-crank lever L
mounted by the side of the hammer lever H on the same axis. The
other arm of the lever L is turned a little to one side at so as to
present a nose in the same plane with and immediately behind the nose
of the hammer lever. The lever L rests in a notch in the side of the
hammer lever H on the lower shoulder thereof. When a peg P of the
barrel passes under the nose of the hammer lever so as to raise the
hammer from the string, the shoulder of the notch in the hammer lever
acting on the lever L raises the rod R and withdraws the damper D from
the string. The peg P having passed the nose of the hammer lever the
hammer is discharged striking the string, but the same peg P having
now come under the nose 7 of the damper lever, as shewn in Fig. 1,
keeps up the damper until the peg has passed that nose, whereupon the
damper again falls against the string and stops its vibration. Thus after
the stroke of the hammer on the string the sound of the latter is sus-
tained while the peg P passes the nose 7 of the damper lever.
When it is desired that a note should be sustained for a longer period
I make the peg of the kind shewn at P¹ consisting of a simple peg p
succeeded by a peg p' of staple form with sloping terminations. The
peg praises the hammer and discharges it as already described, after-
wards sustaining the damper while it passes the nose 1, but before the
peg p has cleared the said nose the hammer is again lifted by the
staple p¹, the shoulder of the notch in the hammer lever keeping the
damper up until the staple peg p³ passes the noses of both the hammer
and the damper levers. The rear of the staple peg p¹ being sloped off,
the hammer instead of being discharged suddenly from it so as to strike
the string is allowed by the passage of the sloped portion to move
gradually towards the string without striking it.
Although in the Drawings I have shewn the damping apparatus
applied to a string, it is obvious that a similar construction and arrange-

page_text: ment are applicable when sounding bodies other than strings, such as
bells or springs are employed.
It may also be readily understood that a similar construction and
arrangement are applicable when the acting pegs instead of being on a
revolving barrel are on a plane or other travelling surface.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I claim, the use in combination
with the ordinary hammer action of an automatic musical instrument, of
dampers worked by the hammer levers, and by the pegs of the barrel or
other travelling surface, substantially in the manner and for the purposes 1
herein set forth.
In witness whereof, I, the said Daniel Imhof, have hereunto
set my hand and seal, this Fourth day of July, in the year
of our Lord One thousand eight hundred and seventy-four.