Improvements in or connected with Mechanical Musical Instruments.
Year: 1894

page_text: Date of Application, 21st June, 1594-Accepted, 15th June,
1895
COMPLETE SPECIFICATION.
Improvements in or connected with Mechanical Musical
Instruments.
1, FERDINAND PIETSCHMANN of 25 Brunnenstrasse, Berlin in the Kingdom of
Prussia, in the Empire of Germany, 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 improvements in the so-called automatic or mechanically
played musical instruments, principally of the kind in which a scale of metal reeds
is played or vibrated by mechanical means under control of a travelling music
sheet carrying the tune in the form of perforations or projecting lugs in a manner
as is well known.
The improvements of my invention have reference, first, to improved means for
vibrating or striking the metal reeds through the medium of a ratchet wheel unler
immediate control of the music sheet and also to apply a damper to the reed at the
proper time, the said damper being actuated by another ratchet wheel rigidly
connected to the wheel which serves to strike the reeds.
Another part of my invention has reference to an improved construction and
shape of the lugs or projections raised from the metal of the music sheet to strike
the reeds.
A further part of my invention has reference to improved means of mounting the
ratchet wheels destined to strike the reeds, as also to apply the dampers, on their
common shaft by means of a springy sleeve, or by separate springs interposed
between the said ratchet wheels and their shaft.
And, finally, my invention relates to an improved mode of fastening the sound
board to the casing of the musical instrument.
The first part of my invention is illustrated by Figures 1, 2, 3, 4 and 5 of the
accompanying drawings.
Figures 1, 2, and 3, being side elevations showing different positions of the
essential parts.
In Figure 1 the parts are shown keeping their normal position of rest;
In Figure 2 they keep the position immediately before striking the reed, and in
Figure 3 the position after striking the reed.
Figure 4 is a view against the other side of the ratchet wheel and
Figure 5 a front view of the same.
Each of the reeds a has mounted opposite to it, on a common shalt g, a ratchet
wheel, the teeth of which are under immediate control of the tune sheet N,
travelling in the direction indicated by the arrow, the said teeth of the wheel b,
being engaged by the perforations of the said sheet, as illustrated, or by projecting
If collapsible
lugs of the said sheet, which serve in lieu of the said perforations.
music sheets consisting of jointed lengths are employed, 1 prefer to use perforated
sheets which offer no difficulty in being folded or piled up, as is the case with sheets
having projecting lugs, but in some cases, sheets or circular discs with projecting
lugs are of good service and even preferable. As the said wheel is being turned,
one of its teeth will come to strike the reed a, the vibrations of which produce the
sound. The said wheel is guided within a slit of the block c, supporting the
shaft the said slit is of sufficient width to leave room for another ratchet wheel d,
A wire
of smaller size and made integral with or rigidly connected to the wheel b.
spring, or small rod of elastic steel, is arranged to fulfil a double purpose, serving

page_text: partly as a damper to the reed and partly as a means for pushing the combined
wheels and upwards against the travelling sheet. The said spring has a
peculiar shape being so bent to form a lug projecting towards the smaller wheel d
and bearing against the circumference of the latter. When the said lug of the
spring/takes the position indicated in Figures 1 and 3, entering into the recess
between two teeth of the wheel d, the said spring will act a pressure against the
said wheel which tends to turn the same to the right, whereby I obtain, that, as
soon as a perforation of the music sheet arrives opposite the uppermost tooth of
wheel, the said tooth is forced to enter the said perforation, so that, as the sheet
is travelling on, the edge of the perforation will positively engage the tooth and
give the wheel & a partial turn. By such partial turn another tooth of wheel b
will engage the reed a and vibrate the same; at the same time the smaller wheel d,
is carried along with the wheel and its tooth will bear against the spring and
bend the same forward towards the reed, as clearly shown in Figure 2. The teeth
of the two wheels band d are so placed in relation to each other, that, before the
tooth of wheel actually strikes the reed, the spring is forced by the tooth of
wheel d to make contact with the forward end of said reed, thereby damping the
same before it is vibrated. In the moment, when the reed is being struck by the
tooth of wheel 4, the spring has been lifted from the reed by its own elasticity,
the tooth of wheel d, which had forced it into contact, having moved on by this
time. It will be readily understood, then, that each vibration of the reed is
preceded by the application of a damper, but that the latter leaves the reed free to
vibrate as soon as it is engaged by the striking tooth. As will be seen in Figure 3
the lug of the spring when the latter has receded from the reed, engages again
into a recess of wheel d and arts a pressure against the lower side of its tooth,
tending to turn the said wheel d to the right, as before, till another perforation of
the travelling sheet comes opposite the next tooth of wheel b. If instead of n
perforated music sheet, a sheet or circular disc with projecting lugs he employed,
the said spring will equally act to obtain a positive engagement of the lugs of the
sheet with the teeth of wheel b. The pressure of spring against wheel d, will
place the topmost tooth of wheel & directly into the path of the lugs of the travelling
Sheet, and by this means, the said logs will be prevented from idly passing by the
teeth to be struck. Owing to this positive engagement obtained, the lugs or
projections of the travelling sheet or disc can be of inferior height, than had been
hitherto required, without diminishing the certainty of their due function.
The same effect derived from the spring as before described, not considering as
neting as a damper, may be obtained by mounting the ratchet wheel, loosely on
its shaft and placing a spring between the said wheel and shaft. Constructions of
this kind are illustrated by Figures 14, 15, 16, 17, 18 and 19.
Figure 14 represents the shaft common to the whole series of ratchet wheels / ;
rotary motion is in this ense imparted to the shaft g through the wheel in gene
with the driving gear of the instrument. The wheels are rotated by both th
spindle g and the travelling tune sheet as will be hereinafter described. The said
shaft has a groove ' extending in the direction of its length, and into sail
groove engages the deflected inner edge of an open tube or shell of steel or springy
metal, ns shown in Figure 15. The central aperture of the ratchet wheel is of
greater diameter than that of the shaft g, so that the said tube or shell may be
placed between the wheel and shaft g, as shown in Figures 16 and 18.
The springy open tube has the tendency to extend, when compressed by the
wheel, slipped over the said tube, and owing to said pressure of the spring,
the wheel is constantly forced to bear with its teeth against the travelling sheet. N.
Figure 18. Accordingly, as a perforation of the sheet is being placed opposite the
tooth of wheel 6, the said tooth will readily enter the perforation and be engaged by
the edge of the travelling sheet, thereby being turned to strike the reed, as
described with reference to Figures 1, 2 and 3. Or, if the music sheet has
projecting lugs instead of perforations, the topnost tooth of wheel 6 will be
placed into the path of the projecting lugs by the agency of said spring i, to

page_text: be positively engaged by the lugs of the sheet. The spring i, placed between
the wheel and its shaft g, compels the said wheel to follow the rotary motion
of the shaft, but at the same time it acts as a brake. The open tube or
shell, instead of being secured to the shaft g by engaging the groove 7', may
be mounted in any other suitable manner, for instance, by riveting or screwing
its sides as at k, to the shaft; in this case, the groove and the inward bent
edge may be omitted. And, instead of mounting the whole series of wheels b
on a common tube or shell, each wheel may have a separate spring, as
shown in Figure 19. said spring / being placed between the wheel and axis g,
acting there in the same manner as the open springy tube/
It will be understood that the shaft g, receiving motion from the driving gear
through wheel, is rotating on in continuous motion and equal speed. The wheels b,
being loosely placed on the interposing shell or spring, would be carried along
in the continuous motion of the shaft, if the frictional resistance acted by the
travelling music sheet N against the topmost tooth of said wheels, did not
prevent such motion, the said resistance being stronger than the friction of the
tube or spring 1, against the inside surface of the wheels b. Now, as soon as
a perforation of the travelling music sheet comes opposite the topmost tooth of
one of the wheels b, the frictional resistance of the sheet N against said wheel
will cease and the respective wheel will be carried along by the shaft,
thus turning up the topmost tooth to project into the perforation, where it will
be struck by the rear edge of said perforation and thereby receive a positive
impulsion to strike the reed. The wheel, is then further carried on by the
common shaft o, until the next tooth will rest against the surface of the travelling
sheet N, which prevents further rotation, as described, till the next perforation
appears opposite the said tooth.
As I have stated before, instead of actuating the ratchet wheels by means of
perforated music sheets, metal sheets or discs may be employed with projecting Ings
that strike against the teeth of the said wheels.
The said lugs or projections usually employed consist of small tongues pressed out
of the metal of the sheet, which tongues, however, are liable to being broken or
being deformed.
One part of my present invention consists in providing improved lugs, which
project so much from the surface of the sheet as to positively engage the teeth of
the ratchet wheel, and, nevertheless, are possessed of extraordinary resistance
against breaking or being deformed.
Figure 6 is a plan of a portion of a music sheet carrying lugs or projections
constructed according to my invention; Figure 7 is a longitudinal section through
the said lugs, and Figure 8, a longitudinal section through lugs of a slightly
modified shape. The lugs or projections have the shape of a bridge, extending in
the length of the staves; the length of the two sides of the triangular lugs may be
equal or unequal, the apex of the triangle may be pointed or rounded off. The said
bridge-shaped triangular lugs are raised from the metal by means of special
mechanism, which forms no part of this invention; their height exceeds that of the
Ings usually employed without impairing their rigidity and resistance. I am aware
that lugs or projections on music sheets, pressed from the metal in the shape of a
bridge, have been employed before, but not in the longitudinal direction of the
staves said lugs, extending across the staves, require considerably more space on
the music sheet and strike against the ratchet wheel with their broad side, while
the improved lugs of my invention may be placed closely to each other in the length
of the staves and strike the ratchet wheel in their longitudinal direction. Owing
to the latter circumstance, the said lugs are not in the least liable to breaking, in
spite of their unusual height, which ensures their positive engagement with the teeth
of the wheel.
Figures 9 and 10 illustrate another modification of the lugs described before.
The lugs of this modification are, first, stamped in the triangular shape, as shown
in Figures 7 and 8, and subsequently one of the sides is subjected to the operation
.R

page_text: of a special tool, which bends the said side inwards to form an angle, as clearly
shown in Figure 9. By this operation the sides of the lng receives a vertical or
Dearly vertical position, enabling the log to better engage the tooth to be struck.
Figure 10 is an underside view of a portion of the music sheet provided with lugs
having a bent side s. The edges of the slot, from which the lug r, has been raised,
are crimped, as at f, to prevent the lug from being forced back through the said
slot. The height of the lugs r. is not diminished by bending the side, into the
angular shape, as shown.
Figures 11, 12, and 13 represent, respectively, a side view, a longitudinal section
and a plan of a portion of a music sheet provided with lugs or projections of another
modification. The lugs are raised from the metal of the sheet in a vertical or
nearly vertical position, and re-inforced by a boss r, not, extending to the full height
of the lugu, but forming a counter pillar to increase the resistance of the lug. If
the said boss, was raised up to the full height of the lug, the metal would break
in stamping the boss of such height.
My invention, finally, relates to an improved mode of securing the sound board
to the easing of the instrument. In the musical boxes hitherto used, the sound
board is permanently secured to the casing by being glued to ledges or bars of woul
attached to or forming part of the casing.
According to my present invention, secure the sound board removably by
means of a spring, which holds the board tightly pressed up to the casing, thereby
giving it the desired tension, and at the same time offering great facility in removing
and replacing the sound board, for the purpose of obtaining rendy access to the
interior of the casing, where the mechanism of the instrument is lodged, to make
repairs or for cleaning or grensing the working parts.
In the drawings, this part of my invention is illustrated by Figures 20 and 21,
the former being a longitudinal section of the casing of the instrument, and the
latter an underside view of the same.
n, is the casing, having ledges or bars of wood p, secured to it as usual, to
support the sound board in. The said sound board, instead of being glued or
rigidly secured to the said ledges p, is held up to the same and in close contact by
the pressure of a spring o, which, in its normal state, is curved as indicated by
dotted lines in Figure 20. At or about its central part the said spring o, is secured
to the sound board m, by a screw of or rivet, on which the spring may freely turn.
Below the sound board and flush with its lower surface, grooves ', are provided in
the sides of the easing a, and on turning the spring », into a position vertical to
the sides of the casing, as shown in Figure 21, the ends of the spring, being forced
down upon the surface of the board m, will enter into the said grooves which
lock the spring in its flat and strained position, as shown in Figure 20. The spring
by its permanent pressure keeps the sound-board tightly up to the ledges p, and in
the desired tension. If it is desired to remove the sound board, the spring o need
only be turned into the position indiented by dotted lines in Figure 21, and the
ends of the spring losing their hold within the grooves n', the board is at once free
to be taken off.
This mode of fastening the sound-board not only serves for conveniently
removing the board ocensionally, but it also improves the sound, as the board, kept
in the proper tension, is not rigidly connected but allowed to vibrate freely.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. In a mechanical musical instrument, mechanism for vibrating the reeds and
also for damping the same, consisting of a ratchet wheel under control of the
travelling music sheet or dise, a smaller ratchet wheel rigidly connected or integral
with the other one, and a spring wire or bar bent to form a lug bearing against the
smaller wheel, said spring serving simultaneously to force the combined wheels into
their proper position for being positively engaged by the travelling sheet, as also

page_text: to be applied as a damper against the front edge of the reed at the exact time
before the reed is being vibrated, substantially as described.
2. In a mechanical musical instrument, mechanism for vibrating the reeds by
means of ratchet wheels loosely mounted on their common shaft with an open
springy tube common to the whole set, or a separate spring for every single wheel,
interposed between the wheels and their shaft, substantially as and for the purpose
set forth.
3. In a mechanical musical instrument having mechanism to vibrate the reeds by
wheels under control of a travelling music sheet or disc, a sound board removably
secured to the casing by a curved spring pivoted to the sound board and engaging
with its ends grooves or recesses of the casing, to lock the sound board in proper
tension, substantially as and for the purpose described.
4. In a mechanical musical instrument operated by the control of a travelling
music sheet or disc, a music sheet or disc having lugs or projections of triangular
shape raised from the metal of the sheet and extending in the direction of the
length of the staves, substantially as and for the purpose described.
5. In a mechanical musical instrument operated by the control of a travelling
music sheet or dise, a music sheet or dise having lugs or projections of triangular
shape raised from the metal of the sheet or disc and extending in the direction
of the length of the stuves, the said lugs having one of their sides bent inwards to
form a steep side, substantially as and for the purpose described.
6. In a mechanical musical instrument operated by the control of a travelling
music sheet or disc a music sheet or disc having lugs or projections raised from the
metal of the sheet or disc, said projections being backed by a boss integral with
the projecting tongue but not extending to the full height of said tongue,
substantially as and for the purpose described.
Dated this 20th day of June 1894.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.