A MECHANICAL " PIANO WHICH MAY ALSO BE PLAY
Year: 1885

page_text: COMPLETE SPECIFICATION.
I, PETER JENSEN Fel. Inst: P.A of 33 Chancery Lane in the County of
Middlesex do hereby declare the nature of said Invention for A MECHANICAL
"
PIANO WHICH MAY ALSO BE PLAYED IN THE ORDINARY MANNER (a communica-
tion to me from abroad by Messra Gavioli & Co of Paris France Manufacturers)
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :—
The instrument which forms the object of the present Invention, is a new com-
bination of a piano provided with an ordinary key board, with pneumatic levers
and perforated cardboards ribbands or sheets made of paper or other suitable
material which is used as a means for the reproduction of music.
This combination is contained in the same case as the keyboard and the
mechanism of the piano, and the mechanism of the pneumatic levers is modified
simplified and specially combined, and the whole of the mechanism adapted to the
working of the perforated paper in such manner that the new mechanical piano
may serve when required as an ordinary piano, to be played in the usual manner
by means of the key board or may be played mechanically.
Heretofore the different systems proposed for these two ends have been defective
whether as regards mechanical organization or in the elements employed for the
reproduction of the music (either by perforated card-board or barrel) or in the
musical execution which they produce automatically and which sounds too much
like the action of a machine.
The mechanical piano leaves nothing to be desired in these various respects in
comparison with other arrangements. In the first place the general working of the
working mechanism placed inside in the upper part of the case does not alter
the general appearance of the instrument which retains all its elegance. Next the
employment of the pneumatic levers rendered most simple and suitable to the
working of the perforated cardboard, permits a great delicacy of the automatic
execution of the music and at the same time all the effects of the touch by the
11

page_text: possibility of varying the pressure of the air which acts on these levers may be
obtained. As the employment of perforated cardboard for the musical reproduc-
tion is infinitely superior to the cardboards or barrels usually employed in the
known mechanical pianos, for these two means cannot be applied to ordinary
pianos without causing either an alteration in the length of the notes or a bad
effect in the percussion of the hammers, moreover they are expensive not easily
manipulated and the barrels especially are too cumbersome to allow of a very
complete repertoire.
But the combination of these three things in the same instrument namely the
keyboard for the execution of music in the ordinary way, the pneumatic levers for
playing automatically with expression, and the perforated card board, as a means
of reproducing the music.
This combination constituted a very complicated question to be solved, which
because of the space occupied by the keyboard of the piano and the arrangement,
complications and ordinary dimensions of the whole pneumatic mechanism
necessitates the simplification and reduction in order to practically facilitate
-the application of cards in the same piano.
The mechanical piano solves the problem completely. There above all the
principal points which form the synthetic combination forms with the accessory
parts the new mechanism which constitutes this new mechanical piano.
1° The combination in the piano itself provided with an ordinary key-board of
the general arrangement of the pneumatic levers and the mechanism relating to the
working of the perforated cardboard.
2° The position of the playing mechanism properly speaking, comprising the
pneumatic arrangement and the mechanism relating to the working of the card in
the upper part of the case of the instrument and allowing of independent playing
on the key-board itself.
3° The direct action of the pneumatic levers on the mechanism of the hammers
to obtain the best effect possible with the exertion by doing away with all necessary
weight which causes a sensible loss of the motive power, whilst it acts by the
employment of a force, the action of which is intermittent like that of the
pneumatic levers, which is subject to the intermittent action depending on the
motion of the cardboards.
4° The new disposition of the arrangement of the small bellows or pneumatic
levers working in the reverse way, that is to say by means of the rarefaction of air.
This arrangement independently of the whole mechanism which it includes and
which offers a great security for the working of the means employed is charac-
'terized; firstly-By the outside position of all the springs which act on the
introduction and equilibrium valves of the small bellows. These springs are
placed in such a manner as to be easily taken off, adjusted and examined.
Secondly-By the combination of the introduction and equilibrium valves
relatively to the differential pressure of the air which acts on their surfaces, which
combination by a powerful action of the pneumatic levers causes the smallest
possible resistance to the action of the cardboards when the said cardboards cause
the top of the keys which have entered to come out of the apertures. In order to
appreciate the importance of this combination, it should be remarked that in the
working of a pneumatic lever each of these two valves is submitted to the
differential pressure produced by the difference in the density of the air which acts
on the two opposite surfaces of the valve. But this differential pressure may tend
either to bring the valve close to its orifice or to withdraw it, there are four
possible combinations therefrom by the position of the two valves relatively to this
differential pressure, or rather this position may be such that the differential
pressure will tend to bring the valves of introduction and equilibrium together to
their respective apertures (or valve seatings) that is to say to shut them, or to open
say the one or the other valve-or to open the introduction valve and shut the
equilibrium valve or lastly to open the latter and shut the former. The last com-
bination is the one which has been found most suitable to be used in conjunction

page_text: with cardboards. In fact it favors the rarefaction of the air in this sense that all
the introduction valves naturally tend to close when they are submitted to the
differential pressure; so much the more as the equilibrium valves tend to open
under the same pressure. The consequence is that the perforated cards in order to
bring back the ends of the keys which have penetrated into their openings, have
only to overcome at the commencement and during a great part of the depression
of the keys, the difference between the resistance of the springs which open the
introduction valves and close the equilibrium valves and the differential pressure
acts in the contrary manner on the equilibrium valves The other very weak
springs which act only to facilitate the bringing back of the introduction valves
against their orifices or seatings bave not yet been mentioned these springs are
very weak and in short are the resistances which the perforated cardboards have to
overcome.
It is not the same with the three other combinations which, by the same force of
action of the pneumatic levers, determine the higher resistances to the cardboards,
during the movements relative to the lowering of the tops of the keys.
5° The particular arrangement of the springs which act on the valves of the
small bellows: and the very practical and efficient means, employed for mounting
the small squares for work in these valves.
The springs and especially those very important ones which serve to open the
introduction valves and to shut the equilibrium valves, and which constantly tend
to make the ends of the keys penetrate into the apertures of the cardboards which
latter are presented to them, are combined in such a manner as to avoid all
perceptible friction to the points of contact and so as to be easily regulated in place
to different tensions without losing their elasticity.
The means employed for mounting the small squares consists in making a small
elongated aperture at the end of each of their arms, such apertures being enlarged
in the middle for the insertion of a wire pull, and then to introduce there a double
packing of cloth or leather, the ends of which are brought together over it on each
side and sewn or glued together. The wire pull passes through the two packings,
and this enlarged opening.
6° The reduction of the wind-chests of the pneumatic levers to two superposed
windchests, for obtaining a sensible diminution of the place occupied by the
appliance generally.
7° The position and working of the bellows pumps to the right and to the left
of the space occupied by the pneumatic levers. This very favorable position
contributes not only to the considerable reduction of necessary space for the general
installation of the mechanical appliance but it also makes it possible to adapt these
bellows pumps, arranged in two pairs, at the ends (disposed in the wind trunk) of
the lengthened table of the upper wind chest an arrangement which permits of the
collecting of all the principal parts of the general system together by connecting
them with the table of the upper wind chest and thus previously giving facility to
mount the whole system to be adapted to the instrument afterward without
difficulty. Moreover, this facility of mounting the automatic or mechanical
arrangement very easily allows of transformning an ordinary into an automatic
Iechanical piano, by adding a box to the upper part for containing the mechanical
appliance.
8° The position and arrangement of the bellows reservoir at one end of one of
the pairs of bellows pumps, and within reach of the freehand, in such a manner as
to be able to act directly, without intermediate mechanism, on the upper table of
this bellows reservoir, so as to be able to vary the density of the internal air or air
contained therein, and thus to obtain the effects of expression.
9° The new means employed for the introduction of the carboards between the
conducting rollers and their disengagement at the end of a piece, without being
pressed, either the rollers, or the ends of the keys which tend to penetrate in the
openings of the cardboards,

page_text: This new mode presents, independently of the complicated mechanical arrange-
ment that it comprises and which will be described further on, certain essential
characteristics which are as follows:-
1° The annulment of pressure from the conducting and circularly grooved rollers
on the cardboards obtained, not by the removal of the rollers with augmentation
of tensions from their springs, but by the slackening of the same springs and the
removal of the rollers which requires the employment of a much smaller force.
2° The combination of this slackening with the resistance to be overcome for
depressing the keys and vice versa of the resistance for distending the springs of
the rollers with the slackening produced by the rising of the keys left free in such
manner that the two pressures to overcome for the introduction and disengagement
of the cardboards, the pressure of the rollers and that of the (top of the) keys, to
sum up instead of augmenting are lessening which also contributes to the
diminishing of the necessary force to the working of the system, altogether in
permitting of the employment of not more than one handle.
In order that this invention may be more fully understood I will describe the
same with reference to the accompanying drawings of which Figure 1 is a side
elevation partly in section shewing the several parts of the mechanical construction.
Figure 2 is a longitudinal section of the part of the piano containing the
mechanical construction.
Figure 3 is a part side secțional elevation of one of the pneumatic levers of the
mechanical piano.
Figure 4 represents a back view of the arrangement of this lever.
Figure 5 represents the square 4 alone out of its place.
Figure 6 is a part longitudinal. vertical sectional elevation of the whole apparatus
relating to the introduction and disengagement of the cardboards.
Figure 7 is a part transverse vertical sectional elevation of the same.
Figure 8 is a diagram representing the positions of the handle above the rollers
and parts relating thereto.
Figure 9 is a modification of the arrangement shown at Fig 6.
Figures 10 and 11 Sheet 2 represent modifications of the pneumatic levers and
valves and Figures 12, 13 and 14 are diagrams illustrating the chromatic scale and
the action of the pulls.
Referring to figures 1 and 2.
a a is a jointed perforated cardboard for the reproduction of music.
bbare stands for receiving the perforated cardboards and serving for their
folding and unfolding;-they are jointed at c and c¹.
dds are rollers covered with india rubber for conducting the cardboards which
pass between these rollers.
e is a chain wheel for actuating the lower roller which conducts the cardboards
and which receives motion from a chain wheel e¹ fixed to the shaft g of the
handle.
h is a series of keys the noses or tops of which enter into the perforations in the
cardboard, into which they take.
i is a metallic roller with circular grooves into which the tops of the keys h can
enter. The grooves correspond to those of the same division of the plate j
(Figure 6) which serves to guide the tops of the keys h.
k is a row of rods with the slanting arms for the connection of the keys with
the mechanism of the pneumatic levers by means of the horizontal pulls m on the
right and of the horizontal guides n on the left and of the releasing wires o. The
slanting arm b of every rod k (Figure 3) is composed of two pieces, one part being
made of metal screwed to the rods k the other part of wood screwed to the metallic
piece and the wooden piece serves for the reception of the releasing wire.
A A are wind chests of the small bellows or pneumatic levers p.
B B B B are bellows pumps for the purpose of rarefying the air contained in the
bellows p the air conduits and the reservoir bellows C. .

page_text: These bellows pumps, which form two couples, are put in play by two cranks
at the back on the shaft g of the handle w in the direction shewn by q and q¹
Figure 2 and lever shafts r and small cranks 8.
The communication of the air contained in the bellows pumps, the bellows
reservoir and the windchests is made by means of the conduits arranged between
the two bellows pumps of each couple at the extremities of the table of the upper
windchest by the air opening, fastened to the bellows reservoir to one of the
extremities of the upper windchests and by the conduit made in the cross pieces
which fix the lower windchest to the upper windchest.
The bellows reservoir C is kept open by means of a spring Z placed between the
two tables. But, when the bellows pumps act, the upper table lowers itself by the
rarefying action of the pumps and it is the flexure of the spring which determines
the degree of rarefaction of the internal air, and correlatively, the differential
pressure of the external air on the upper table of the reservoir C.
t are pulls by means of which the small bellows act directly on the balances u
of the escapements, for the striking of the hammers. Each of those pulls as shown
in Figure 1 is formed of two parts the one part being hooked on to the other, the
lower part passes in a guide fixed to the framework of the mechanism of the piano,
and it is enough to unhook the upper part to be able to withdraw this mechanism
when required.
For the application of the mechanical arrangement in pianos in which the
balances of the escapements have not been prepared with the view of this
application, or a row of counterbalances might be added to which the pulls t
would be connected and which would actuate the balances of the escapements.
Referring to Figures 3 and 4.
1, is the introduction valve of the small bellows or pneumatic lever p serving
for the introduction of the internal air of these small bellows into the interior of
the windchest A where the air is rarefied by the bellows pumps B.
2 is the equilibrium valve, which shuts when the introduction valve opens and
vice versa opens when that closes. In the first case, it establishes equilibrium
between the internal air of the small bellows p and the rarefied air of the wind of
the conduits and of the bellows reservoir. In the second case it establishes
equilibrium between the exterior and the internal air of the small bellows which
has been rarefied. These two valves are fixed to the rod 3. They work in a
circular cavity and there is a row of like circular cavities for the whole row of
pneumatic levers of a windebest, each isolated from the other and shut by the
cross bar where the orifices of the equilibrium valves are made. The rod 3 which
carries the two valves, is guided at one of its extremities by the upper arm of the
square 4, which it goes through, the other extremity where the introduction valve
is has no other guide than the nut 5 which because of its form and the weight of
the rod and the bend of the orifice of this valve always tends to bring it (the
valve) back into the same position; which gives a great freedom of movement to
the valves.
6 is a double action spring which by means of the square 4 of the releasing
pull o of the rod k of the pull or guide which connects this rod to the corresponding
key and to the top thereof causes the said top of the key to enter into the
openings of the cardboard as soon as it encounters them, and besides to open the
introduction valve and to shut the equilibrium valve as soon as, during the release
of the spring, the upper arm of the square 4 encounters the nut 7 fixed to the
rod 3.
8, is a spring bringing the valves back the action of which stretches according
to the differential pressure which opens the equilibrium valve and shuts the
introduction valve when the double acting spring 6 is brought back into the initial
position by the action of the cardboard on the top of the corresponding key.
Now the following shews the general arrangement of the pneumatic lever p
bearing in mind the preliminary condition for the working of the cardboards that

page_text: is to say the putting in tension of the conducting rollers and the circularly grooved
roller.
When the cardboard is under the circularly grooved roller, the top of the
key connected to the pneumatic lever p which is actuated by the tension of the
spring 6 comes against the lower surface of the cardboard. The introduction valve
is then shut and the equilibrium valve open; this position is shown on Figure 3.
A little play should be allowed between the nut 7 and the upper arm of the
square 4, to ensure the complete closing of the introduction valve. Supposing
the cardboard were moving, an opening comes forward over the top of the key h
this top or nose immediately enters the opening, by the action of the spring 6 on
the key by means of the intermediate parts described.
But the spring 6 also acts on the upper arm of the square 4, which in rocking
encounters the nut 7, draws the rod 3 which then opens the introduction valve
and shuts the equilibrium valve. It is owing to this second action of the
arrangement that the rarefaction of the internal air of the small bellows is
established and that the differential pressure of the external air acting on the
external surface of the small bellows, forces it to shut and to produce the percussion
of the hammer connected thereto by means of the pull or rod t which directly
commands the balance of the escapement or action connected thereto. The small
bellows are then always closed when the top of the key is in an opening or
perforation in the cardboard, but as soon as it comes out by the action of the card,
the two valves brought back by the same intermediate means, again taking their
initial positions, equilibrium is reestablished between the outer and inner air of the
small bellows and this latter opens again the same instant and retakes its former
position.
It is the same with all the pneumatic levers of the mechanical piano, every time
that the openings are presented above the tops of the keys during the movement
of the cardboards.
Referring to Figure 5, 4 is the square alone out of its place before its arms have
been twisted as shown in Figures 3 and 4, g, gl, are the small apertures which have
been before mentioned and in which are introduced the necessary appliances.
Figures 6 and 7 show the whole apparatus relating to the introduction and dis-
engagement of the cardboards and consists. Firstly-Of a kind of metallic box D
in which are arranged in the bearings d¹ the upper roller d for the conduction of
the card boards and the roller i with circular grooves, as well as the springs E E,
acting on the bearings of the rollers d and i¹. These springs are fixed to the plate F
which forms the top of the box, and which springs may be expanded more or less
by means of the adjusting screws secured in the plate F.
The box D has two projecting pieces which are jointed at G to two fixed supports
opposite to each other on the longitudinal cross pieces of the framework of the
mechanism of the cardboards; and when it is lowered as shown in Figure 6, that
is to say in the position which allows of the working of the cardboards, the bearings
of the upper rollers are suspended over their supports which form part of the box.
Secondly-A spindle H with handle I and mounted in two bearings in the front
of and made in one with the metallic box and to the ends of which two levers K
are jointed eccentrically at J opposite each other one only of which is shown in
Figures 6 and 7. The fulcra of these two levers are at L on the two supports
fixed to the cross pieces of the framework of the cardboard mechanism.
This arrangement of parts forms a compound lever with a variable fulcrum,
which facilitates the overpowering of a considerable resistance by a relatively small
force.
Thirdly, a slanting bar M placed near the ends of the keys, and mounted on an
arm jointed at N, which permits it to advance, to slide on the ends of the keys and
to hold them back. This bar M is jointed to the levers K by two corresponding
connecting rods O, jointed at P and Q in such manner that its movement is

page_text: communicated to it by the same movement of the spindle H which acts on the
levers K.
The machine acts as follows:→
The first thing to be considered is the system when in its fixed position which.
results from the horizontal position of the handle I shown in Figure 6 and which
serves for the conduction of the cardboards.
In this position, the spindle H is subjected to a force resulting from the pressure
of the springs E E, and acts on a line in the direction which passes by the axis of
the spindle H and the point of eccentricity J; and has a reactive force from the
fixed shaft L, which because of the rigidity of the lever K, acts on the eccentric
shaft J, on the same line of direction but in the opposite way, which passes by this
shaft, by the axis of the spindle H and by the fixed axis of the lever. These two
forces applied to different points in this same common line, being equal and
directly opposed to each other, create equilibrium there and determine the fixing of
the system.
Now, if the handle I be raised, the spindle H will be caused to turn in the bearings
and as follows, the eccentric shaft J to make a circular movement round this spindle,
but the eccentric shaft being also connected to the lever K cannot there receive
more than the movement determined by the fixed pin L; and as those two move-
ments do not coincide, this eccentric axis reacts on the axis of the spindle H in
pulling in the fixed direction by the jointed axis of the metallic box. Thus three
coexistent movements obtain the elevation of the axis of the spindle H and of the
metallic box D, the rotation of the spindle H and hence also of the turning of the
eccentric round this spindle, and lastly the circular displacement of the eccentric
axis in the direction determined by the fixed axles L and consequently the
displacement of the lever K.
It is during the elevation of the metallic box that the springs E E which press
the bearings straighten, and this straightening operates until the moment where,
these being sustained pressed on their supports, the pressure of the rollers or the
card is annulled. At the same time, the inclined bar M actuated by the lever K
comes near to the ends of the keys h, glides on them and lowers them. By
continuing the course of the handle to the place indicated by I¹, the rollers
contained in the metallic box are raised in their turn and permit the free entry or
exit of the cardboards.
A reverse movement of the handle replaces the metallic box in its first position,
reestablishes the pressure on the rollers and brings the inclined bar m beyond the
ends of the keys which become free.
Referring to Figure 8 which shows the positions of the handle I, of the spindle H
and lever K, as regards the conduction of the cardboards and to the annulling of
the pressure of the rollers on their surfaces-The full lines in the diagram show the.
foriner and the dotted lines the latter position.
Figure 9 shows how the levers K may he replaced by two hooks R of the form
indicated in the drawing. They are fixed to the ends of the spindle H.
In raising the handle I the ends x of these hooks disengage themselves from
underneath the rollers the axes of which are fixed at y and in this manner give to
the springs of the rollers the facility of distending the metallic box in raising the
box. If the course of the handle I is finished, the other ends z sliding on the same
rollers and resting there, still raise the box and hold it suspended at a point where
the removal of the rollers permits the free entry and exit of the cards. In turning
back the handle into the horizontal position the ends of the hooks catch under
the rollers and fix there after having lowered the metallic box and thus reestablished
the pressure of the rollers enclosed in the box.
This arrangement of hooks fixed to the ends of the spindle H has the advantage
of setting free the metallic box from the whole connection which limits the removal,
and consequently renders the complete raising of this box possible on its hinges.
But on the other hand it necessitates the employment of a second handle for
depressing the keys. It may however be used...

page_text: Besides the essential elements which have been enumerated for the mechanical
piano it must be distinctly understood that the pneumatic levers may be applied
direct, that is to say working by means of the compression of the air instead of the
rarefaction of same.
These two pneumatic modes are in reality two different aspects of the same
physical fact: namely, the difference in the density between the internal air of the
bellows and the external air, the latter is denser than the former in the inverse
mode and the internal air of the bellows is more dense than the exterior air in the
direct mode.
.
The application of the pneumatic lever in the direct manner does not elsewhere
change the general arrangement of the mechanical piano. It may even easily be
constructed of the parts before mentioned. It is enough to adjust the tension of
the springs which act on the valves of the pneumatic levers, to alter the position of
the valves of the bellows pumps to put them in accordance with the new function
of the latter, to observe that the bellows reservoir should be shut in the ordinary
position and be subject to the pressure of a spring acting on a movable table, to
adjust and place the wind chests of the pneumatic levers upside down, in order that
the small bellows, which would then naturally shut by their own weight to open
under the action of the compressed air, worked like pulls which would be connected
to the balances of the escapements, to replace the return pulls by the guides and
to give an inverse position to the slanting arms of the rods k.
In short, if the pneumatic levers are required to be applied in the direct manner,
under the same conditions which have been pointed out in the inverse manner for
the position of the introduction or inlet and equilibrium valves, relatively to the
differential pressure of the air which acts on their surfaces, a position of which the
advantages have been explained, the arrangement must evidently be modified to
adapt it to the inverse mode as shown in Figure 3, by disposing the valves in the
direct mode to conform to the action of this differential pressure and place the
springs and nuts in conformity with this arrangement.
Figure 10 represents another arrangement of valves for the pneumatic levers p
which arrangement is a modification of the foregoing. The valves 3 and 4,
mounted on the same valve rod t t are the compensation valves of the inlet valve 1
and equilibrium valve 2. o is a circular conduit which goes from the interior of
the air chamber C to the outside and communicates with another circular
conduit o¹ which communicates with the interior of the pneumatic lever p.
It is evident that when the valves 1 and 3 are shut, the differential pressure
tends to open the latter and close the former, and, in like manner, when the
valves 2 and 4 are shut the differential pressure tends to open the one and to close
the other; which precisely neutralizes the effect of this pressure on the valves 1
and 3 and on the valves 2 and 4 and it will be understood that by properly
apportioning the aperture of the valve 3 and relatively to that of the valve 1 and
the opening for the valve 2 relatively to the valve 4 complete equilibrium may be
obtained between all the like and contrary actions of the differential pressure on
each couple of the valves during the movement communicated by the valve rod t t.
But, as it is practically advantageous to assure the air tight closing of the valves,
particularly of the inlet valves, it is preferable as shown in Figure 10 to make the
valve apertures the same size for all the valves. In this manner the differential
pressure is a little greater on the inlet valve 1, and this by reason of the reclosing
of the valve. This excess of pressure therefore tends to shut the valve 1 and by
the same movement communicated to the valve rod t t which carries the other
inlet compensating valve 3 also to shut the latter. It is the same for shutting the
equilibrium valves 4 and 2. The double acting spring 6 not having to overcome
anything more than the differential pressure on the whole surface of the inlet
valve 1, but only this pressure on the part of the valve which comprises the closing
outside of the opening, may have a very sensibly reduced tension and hence also
will present a much weaker resistance to the cardboards for the total depressing of
the top of the corresponding key.. The helical spring a placed on the valve

page_text: spindle t t between the nut b and the upper arm of the square c is instead of the
pull back spring 8 of Figure 3 Sheet 1. It serves like the latter to facilitate the
bringing back of the valves, when the square is brought back in the initial
position by the corresponding key.
Now the valves 1, 2, 3 and 4 are mounted on the valve rod t t in such manner
that the regulation may be very easily made from outside, by means of the nuts d
and e.
A helical spring 9 placed between the two valves 1 and 2, pushes the
valve 1 against the fixed nut i and the valve 2 against the tube j through which
passes the valve rod t t. This tube which may slide freely on the valve rod, is
stopped by the nut d. Another helical spring h, placed between the fixed nut k
and the valve 3, pushes this valve, which pushes the tube on which the valve 4
is placed the closing of which with the valve 3 is regulated by the nut m fixed
in like manner on the tube 7. This closing, regulated previously, invariably
determines the degree of opening of the valves 3 and 4 and consequently their
correlatives 1 and 2.
The valve rods t t are cranked at 8 which parts pass in between the teeth of a
rack u so that the valve rods cannot turn to right or left when the nuts e, d, b, v,
are screwed up or down.
The position of the valve 1 on the valve rod t t is determined by the fixed nut i.
This valve 1 being applied against its aperture, the valve 3 is regulated by means
of the nut 6.
If this nut is screwed up, it pushes against the loose nut n, which presses against
the valve 4, which is mounted on the tube 7, which opens in its turn the valve 3
more or less. If the nut e is unscrewed, this valve 3 is brought back, in like
manner the tube 7 with the valve 4 which it carries, by the expansion of the
spring h. The valve 3 being adjusted, the valve 2 is fixed in position and after
that the valve 4, the position of which is determined by the nut m. It suffices
then to screw up the nut d for making the tube jadvance, which presses and opens
the valve 2 more or less, or to unscrew this nut so that the tube and the valve 2
may be brought back by the spring g.
This combination of compensating valves for each pneumatic lever of the
mechanical piano has three great advantages; that not only does it permit of using
very thin cardboards for the automatic execution of the music, but, by reason, the
doubling of the apertures with the same internal capacity and dimension of each
small bellows or pneumatic lever, it results in a like differential density of the
motive air, a very sensible augmentation of the energy of the pneumatic levers and
consequently of the power of the percussion of the hammers. I add this minute
detail that the pneumatic lever combined with the compensating levers may serve
as well without any change in the mechanism for the inverse pneumatic action (by
rarefaction) as for the direct pneumatic action (by compression of the air).
The second combination for neutralizing the differential pressure on the inlet
and equilibrium valves, consists in the addition for every pneumatic lever of a
compensating appliance subservient to the differential pressure and acting in the
contrary sense to this pressure on the valves.
Figure 11 Sheet 2 shows a full sized sectional side elevation of this combination
adapted to the pneumatic lever of the mechanical piano. is the compensating
appliance in the shape of a little bag on which is fixed a rigid plate which takes
against the extremity of the guide y screwed on to the end of the valve rod t t.
The differential pressure, acting externally on this little bag or pouch, pushes the
guide and the rod on which are mounted the valves 1 and 2 in the contrary sense
to the action of this differential pressure on the valves and in order that there may
be compensation between these two contrary effects of the pressure, the size of the
little bag or pouch and of the small rigid plate are calculated according to the size
of the aperture and the covering of the valves in observing that the effect of the
pressure should be rather a little less on the appliance in order to ensure the
natural shutting of the introduction valve.

page_text: By mounting the valves 1 and 2 (Figure 11 on Sheet 2) on a partly cranked or
bent shaft with a helical spring, tube and nut, as shown in Figure 10 and which
has been previously described the adjustment of the equilibrium valve 2 from
without could be more easily effected.
The comparative examination of Figures 10 and 11 sheet 2 shew that it is also
easy to combine the compensating appliance with the valves 1 and 2 placed like
the valves 3 and 4 of the Figure 10 sheet 2, relatively to the differential pressure
which acts there because it will suffice, without changing the situation of the
appendage x and the guide y, to dispose the double acting spring 6 so that its
expansion may act instead in the contrary sense on the upper arm of the square c
to place the adjusting nut v of the rod in connection with this expansion, and to
replace the bringing back spring a by another which acts in the opposite sense on
the rod t, t.
For the direct pneumatic mode that is to say by compression of the air the
compensating appendage receiving the differential pressure interiorly should be
disposed so as to produce its effect in pulling.
This invention also comprises
1° The manufacture of cardboards or cards, papers or any other materials with
interspaced chromatic perforation in the same chromatic order for the lower and
the upper notes.
A much better distribution of openings on the breadth of the cardboards
relatively to the solidity of the unperforated part results from this arrangement,
the part of the middle taking place at each end at one side with the bass and at
the other with the treble, and at the same time preserving the same chromatic
signification to the bass and to the treble, for the facility of notation. The scale
will be arranged in the rack as shown in Figure 12 Sheet 2.
2° The chromatic interlined arrangement of the guides and pulls or trackers of
the keys.
This arrangement results in a greater space between the guides and also between
the pulls or trackers without complication in the general arrangement which at the
same time avoiding all possible friction between these guides and between these
pulls, gives much more facility for regulating them.
Figure 13 Sheet 2 is an example of the new chromatic interlined arrangement
of the guides and of the pulls.
Figure 14 sheet 2 is an example of the old arrangement of guides and pulls it is
enough to compare this example with Figure 13 Sheet 2 in order to appreciate all
the advantages of the interlined chromatic arrangement as shown."
3° The movement of the metal roller with circular grooves by the lower con-
ducting roller by means of tooth gearing or other mechanism.
By means of this new movement the cardboard has not to overcome the resistance
which the metal roller presented which should really receive its rotary movement
from the cardboard itself. The metal roller being now actuated by a rotary
movement corresponding with that of the conducting roller it also tends to conduct
the cardboards which are underneath by a double conduction, a conduction from
pushing proceeding from the lower conduction roller and a conduction from pull,
proceeding from the circularly grooved roller. It follows therefore that the
resistance which this roller presents when it should be conducted by the cardboards
is annulled and this also to the advantage of the conducting power of the lower
conducting roller.
The grooved metal roller may also be worked direct from the shaft of the crank
handle.
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 as the invention communicated to me is
First The combination in the same Piano provided with an ordinary key
board of the general arrangement of pneumatic levers and of the mechanism

page_text: relating to the working of the perforated card boards, the relative position of the
said parts being substantially as described.
Second-The pneumatic levers p acting directly on the mechanism of the
hammers and arranged as set forth.
Third: The particular arrangement of the springs of the pneumatic levers
placed on the exterior of the surface so as to be easily removed adjusted and
regulated.
Fourth-The particular combination of the inlet and equilibrium valves.
Fifth The particular arrangement of the springs acting on the valves of the
small bellows or pneumatic levers in combination with the squares 4 constantly
tending to make the tops of the keys h penetrate into the perforations of the
cardboards.
Sixth-The arrangement of the windchests of the pneumatic levers in two
superposed rows for obtaining a sensible diminution of the space occupied by the
arrangement in general as set forth.
Seventh-Arranging the bellows pumps to the right and left of the space
occupied by the pneumatic levers as set forth.
Eighth Arranging the bellows reservoir at one of the ends and conveniently
for working, as set forth.
Ninth The new means for the introduction of card boards between the con-
ducting rollers and their disengagement at the end of a piece, without having to
support the least pressure, either of the rollers or of the tops of the keys which
tend to penetrate into the perforations of the cards as set forth.
Tenth The applications of compensating valves and of a compensating appliance
for the mechanism of the pneumatic lever in combination with the perforated card-
boards or leaves of any similar substance for the automatic execution of the music
for the purpose of considerably diminishing the resistances which these cardboards
or such like leaves have to overcome in their working substantially as described
also the arrangement of parts for this purpose as described with reference to
Figs. 10 and 11.
Eleventh-The means employed for the easy and exterior adjustment of the
valves of each pneumatic lever as described with reference to Figures 10 and 11.
Twelfth The chromatic interlined perforation of the cardboards, cards, papers
or all other materials with the same chromatic sense for the bass and treble
substantially as described.
:-
Thirteenth The chromatic interlined arrangement of the guides and of the keys
substantially as described with reference to Figure 13.
Fourteenth-The working of the metal roller with circular grooves by the
lower conduction roller by means of tooth gearing or other suitable mechanical
arrangements.
Fifteenth The combination of parts forming a piano which can be played either
mechanically or in the ordinary manner substantially as described and shown.