Improvements in Pneumatic Devices for Playing Keyboard Musical Instruments.
Year: 1898

page_text: Improvements in Pneumatic Devices for Playing Keyboard
Musical Instruments.
A communication by HENRY GAYLORD WILSHIRE, of Los Angeles, in the County of
Los Angeles, and State of California, United States of America.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of the Agency for Foreign Patent
Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in the
County of Lancaster, 118, New Street, Birmingham, in the County of Warwick, and
322, High Holborn, in the County of Middlesex, Civil Engineer, 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:—
The invention relates to pneumatic piano-players in which pneumatic action, in
combination with bellows, valves and tubes, form the principal parts of the
mechanism.
The object of the invention is,
}
First, to provide a pneumatic piano-player which operates with a much more perfect
action and a finer and more delicate expression.
:
Secondly, to control the entire music and operate the expression pedals, and
rewind the music on the music roll after it has been played, without the assistance of
the operator.
These objects are attained by a mechanism illustrated in the accompanying
drawings, in which
Fig. 1 is a vertical cross-section of the action showing the small bellows, valves,
air-tubes, and frame-work;
Fig. 2 is a front view of a part of the action;
Fig. 3 is a sectional end view showing a striking bellows closed, and a lifting stem
raising a key;
:
Fig. 4 is a side view with parts cut away in section on lines A-B and CD of
Fig. 3, showing the cells, air-tubes, and elbow-couplings;
5.
Section A-B of Fig. 4 shows the cells cut open and the lifting stem resting on
the ends of the bell-crank-pieces and under the ends of the piano-keys;
Section C-1) of Fig. 4, shows the back of the cells with elbow couplings and air-
tubes cut open;
Fig. 5 is a top view of a portion of the air-duct-bridge over which the perforated
paper strip passes;
Fig. 6 is a section of the same on line E-F of Figs. 7 to 10;
Fig. 7 is a side view of a portion of the air-duct-bridge showing holes where air-
tubes are attached ;
Fig. 8 is a section on line G-H of Fig. 9;
Fig. 9 is a section on line I-J of Fig. 8;
Fig. 10 is a section on line CD of Fig. 8;
Fig. 11 is a top view of the check-valve used in this instrument;
Fig. 12 is a section of said valve;
Fig. 13 is a top view of the pedal action

page_text: Fig. 14 is a side view of said pedal action with portions broken away showing valve
action;
Fig. 15 is a plan view of music drawer showing music rolls, metronome, air-duet-
bridge and rerolling devices;
Fig. 16 is an end view of said music drawer ;
Fig. 17 is a side view in two portions of lifter-bellows with lifting-pin attached,
showing vent at a, and inlet an 6%;
Fig. 18 is a cross-section of the same;
Fig. 19 is a front elevation of a piano showing the general arrangement, and
relation of parts in the instrument, the front panel being removed to show pneumatic
parts, relief-valve, z, pedal action, and music drawer.
Horizontal action-rails, B, B, and C, C, (see Figs. 1 and 2), form the supports to which
the vertical striking bellows, D, and the vertical valve-boards, E, are attached, and
form the frame-work of the action which is arranged vertically and is beneath the
piano-keys.
Horizontal flange-rails, F, F, above support the flanges, f, f, and pivoted bell-crank
pieces, G, G. E is the valve-board fastened to frame-work, C, B, and arranged verti-
cally. To the outer face of the valve-board, E, is attached the case-board, H, milled
out so as to form a vacuum-chamber, I. Said case-board, H, is provided with holes
under the horizontal tube-board, J, to which the tubes, K, are attached. On the
inside of case-board, H, are placed lifter-bellows, h, of peculiar construction (which
will be more fully described hereafter).
On the back of valve-board, E, are placed small valve-cells, L, as shown in section
in Fig. 4. Said cells, L., are each provided with vent-valves, t. On the inside of each
cell, L, and resting on the valve-board, E, are check-valves, M, covering a hole in
said board. These valves, M, are of special form (see Figs. 11 and 12, made as follows):
To a thin board of suitable size is attached a strip of soft leather of equal width, in the
following manner: The leather strip is enough longer than the board to admit of the
ends passing round each end of the board and to be glued fast on top only, leaving
the entire length under the board free and sagging, making a perfect check-valve,
which is held in place on valve-board, E, by means of a spring, as shown.
To the outside of said valve-cells, L, (see Fig. 1) are attached elbow-couplings, N,
for connecting with central air-tubes, O, leading to corresponding couplings, N1, on
the striking-bellows, D. Said striking bellows, D, are provided with fingers, f2,
covered with action-leather for striking the bell-crank, G.
In Fig. 2 is shown a portion of the front of the action, the back and front being
just alike, forming a double row of bellows, bell-cranks, etc. The reason for this
double row is on account of the number of parts. There not being sufficient rooin to
admit of their all being in one continuous row, and bring each directly under a key,
they are arranged in a double row, so as to bring a striking-bellows and a bell-crank
under each key of the piano.
•
In Figs. 13 and 14.
is shown the action which operates the pedals of
the piano. There is a vacuum-chamber, r, formed by the top and bottom
boards, R, R, and a suitable marginal strip to keep them the proper distance
apart.
On the top board are mounted three bellows, S¹, S², S³. Bellows, S¹, operates
lever, T', which in turn, operates damper-rod, U. Bellows, S2, operates lever, T2,
which controls expression-rod, V. Bellows, S³, operates lever, T³, which is attached
to a catch or tripping-bar, W, which is pivoted at its lower end and provided with
two catch-blocks, 62, 63, on its face, for catching the end of lever, T2, when it is drawn
down as described hereafter. On the inside of vacuum-chamber, ", are placed lifting-
bellows, h, (similar to those in the action before described).
Under each of the bellows, S1, S2, S3, and inside of each bellows and resting on the
top board is placed a check-valve, N, and to each of said lifting-bellows is attached an
air-tube, K1, K2, K³, as shown in Fig. 14. The vacuum-chamber is provided with an
air-tube, X, extending from top board of same to an air-trunk hereafter more fully
described. All the air-tubes, K, in the striking and in the pedal-action, lead to the

page_text: side of an air-duct bridge, which is provided with holes to receive them as shown in
Fig. 7.
These holes communicate with corresponding small openings on the top (or
edge) of the air-duct-bridge, as shown in Figs. 5 and 8. The Figs. 5, 6, 7, 8, 9
and 10, show the manner in which this air-duct-bridge is constructed.
It is composed of three pieces of wood, or other suitable material, and the central
section, a¹, is thinner than the two outer sections and has its upper edge cut in such
a manner as to form teeth not unlike a comb, so that when the two outer
sections, a², a³, are glued to it the spaces between the teeth form small ducts as shown
in Fig. 5. These ducts extend downward about one-fourth of the total width of the
block, as shown in Fig. 8. The two outer sections are much thicker than the center
section, and are grooved on their inner surface in such a manner as to connect with
each of the spaces between the teeth of the center piece, and said grooves are so
arranged, and of various lengths so as to connect with holes for attaching the
air-tubes.
This arrangement of ducts and grooves admits the attachment of all the tubes to
one side, as shown in Figs. 9 and 10, which is important in assembling and attaching
air-tubes.
The music for this instrument is composed of long strips of paper the exact width
corresponding to the length of the music-roll B2, Fig. 15, and the music is written
by punching holes in this paper, so arranged that when passing over the air-duct-
bridge, A¹, the holes will pass the openings in the said bridge and allow the air to
enter the same in the well-known manner.
. This
The music-drawer as shown in Figs. 15 and 16, contains the music-roll, B2, feed-
drum, B3, gear-wheels, 52, 53 and 54, rewinding-pulleys, 45 and 48, belt, 47, and the
metronome which regulates the speed and operates the rerolling device.
metronome is composed of the following parts: A shaft, 37, collar, 38, shifting-
block, 39, bell-crank, 40, and jointed arm, 41. On the shaft, 37, is mounted
a friction-wheel, 33, which receives motion from the driving-wheel, 35, giving motion
to pinion 54, which transmits the motion to the feed-drum, B³, by means of the
gears 52 and 53.
On the shaft 37, is loosely mounted pulley 45, which drives the
reroll-pulley 48, at the proper time, as hereafter described.
The end of the shaft 37, on which pulley 45, and pinion 54, are placed, is provided
with a movable bearing, 42, on which is arm 43. The jointed arm 41, of the
metronome is provided with a knob and suitable guides through which it passes.
Near the outer end and under said arm is situated a brass spring, 60, screwed to
the end board as shown at 62. This spring is so bent that it presses out against the
arm, so that when the knob is pressed downward, as shown in Fig. 16, the top end
of the spring springs out and into contact with the brass strips, shown at 61. The
object of this spring is to open and close the electric circuit, when an electric motor
is used to run the instrument. When the handle is down the contact is made and
the motor starts, and by raising the arm the spring is pressed back and the circuit
broken and motor stops. The instrument is to be driven by any suitable motive
power such as electric motor, water motor, spring or weight motor, whichever is
most convenient to the owner of the instrument in which it is to be placed. The
action is intended to be made to fit almost any piano or reed instrument (the shape
of parts being modified to suit). When the motor is placed in the instrument it is
so arranged that it gives motion to a shaft at the back of the instrument. This shaft
operates the triple exhaust pumps or bellows, which are made and so arranged as to
fit in between the timbers at the back of the instrument. These pumps or bellows
are connected to a main hellows which is kept expanded by a strong spring. The
main bellows is connected to the vacuum-chambers, described, by an air trunk of
suitable shape and capacity. Therefore, when the motor is started the pumps exhaust
the air from the main bellows, causing it to collapse, also exhausting the air from the
vacuum-chambers. The spring in the main bellows keeps a constant and equal
pressure, so that when air is admitted to the chambers through the tubes the bellows
expand and keep the suction the same, thereby equalizing the irregularity of the
pumps and air admitted.

page_text: The pneumatic action is placed in the front of the piano under the key-board and
close to the strings, so that the front panels may be placed back in position hiding
the entire action with the exception of the music-drawer. (See Figs. 15 and 16).
This music-drawer is hung under the key-board at the right hand side, out of the
way of the person sitting at the instrument, as shown in Fig. 19, and there is
nothing to interfere with playing the instrument in the ordinary way.
Having described the working parts the operation of the instrument will now be
explained.
To explain the action of the instrument, the sheet music, which
roll, B2, is placed in the music-drawer, as follows:
always on the
First, lower the drawer (which is hinged at the back) then place the end of the
roll (which is provided with a flat or square hole) on the end of the small reroll-
shaft 49, then drop the other end of the roll (which is provided with a pivot) into the
recess in the drawer-frame at 618, Fig. 15. Then take the loose end of the music
sheet, which is provided with a small brass ring, and pass it back and hook the ring
into the hook 51, on the feed-drum, giving the drum a slight turn to take up the
slack paper, and then raise the drawer up until it catches and is held by spring-
hook 65, Fig. 16. Start the motor by pressing down the knob on the jointed arm, 41,
which will release spring 60, which latter comes in contact with the plate 61, and
completes the electric circuit. The motor starts at once, the sheet music begins to
move over the air-duct-bridge, and the pumps also being in motion, the air is
exhausted from the vacuum-chambers and draws the sheet music down onto the air-
duct-bridge preventing the air from entering the openings in the bridge, and, there
being no other way for air to reach the vacuum-chamber, as the perforations in the
music reach the openings in the bridge, the instrument begins to play.
The valves, strikes and keys, are operated as follows:
J
As the paper moves, the first perforation in it tends to uncover the opening in the
bridge which allows the air to rush in said opening and through the air-tube, K, to the
lifter-bellows, h, Fig. 1, in the vacuum-chamber, I. This little bellows instantly
opens, and by means of a pin on its side lifts the check-valve, M, in the celi, L, on
the valve-board. This action allows the air to be instantly drawn out of the striking-
bellows, D through the tube, O, causing the latter to collapse and the finger, f2, of
bellows, D, strikes one end of a bell-crank, G, which throws the other end of said
crank up.
A wooden stem, P, rests on the end of elbow-lever, G, and reaches up and
comes in contact with the bottom of the key immediately upon it causing the hammer
belonging to that key to strike the strings. As soon as the paper moves forward
enough to allow the perforation to pass the opening in the air-duct-bridge, the paper
closes it again, shutting off the air. The suction in the vacuum-chamber causes the
check-valve, M, to close forcing the air out of the lifter-bellows, h, through a small
vent, shown at a, Fig. 17, also allowing the small valve, t, in the cell, L, to open,
letting air into the cell and back up through tube, O, to striking-bellows, D, allowing
it to open instantly. This operation is the same in all the keys.
The object of the metronome is to regulate the speed, stop and start the motor,
and operate the rerolling device. All of which is done with the one handle or knob
on arm, 42, in the following manner:
Push down the handle to start, raise it up to stop. If the music is not playing fast
enough pull out on the handle a little, which moves the outer end of bell-crank, 40,
the inner end of which is attached to shifting-block, 39, which when moved to the
left (or downwardly in Fig. 15) draws the shaft, 37, with it by means of collar, 38.
The shaft moving to the left draws the friction-wheel, 36, farther out from the center
of the driving-wheel, 35, thereby increasing the speed of the metronome-shaft, making
the feed-drum revolve faster. The more rapidly the sheet music passes over the air-
duct-bridge, the faster the music will be played. To play slower the action is reversed
(namely) by pushing in the handle.
When the music has run off the music-roll onto the feed-drum, the instrument is
not stopped in order to rewind the music, but it is only necessary to pull the
metronome-handle out to the full-limit. It moves the shaft, 37, so far to the left that

page_text: the small pin, 46, will engage the pin, 46, on the pulley, 45, causing it to revolve
with the shaft, driving the belt, 47, which drives the reroll-pulley, 48. However,
before the shaft, 37, moves far enough to the left for the pins, 46, 46, to engage, a
nose, C3, Fig. 16, on the outer end of the bell-crank, 40, passes under a lug on arm, 43,
which is attached to movable bearing, 42, causing the movable bearing to be tipped
back about the point, h², so as to throw the pinion, 54, out of gear with wheel, 52,
and release the feed-drum, allowing it to revolve backward while the paper is being
rewound on music-roll. When it is all off the feed-drum, the ring on music-sheet
unhooks automatically.
on.
There is still another action which takes place while this unrolling action is going
When the movable bearing tips back (to disengage the gear) it comes in contact
with a crank, 44, Fig. 15, on a small rod, pushing it back. This rod operates a
valve, z, Fig. 19, on the vacuum-chamber opening it to admit air, for as the motor is
still going, and the pumps working, it is necessary to admit air to the vacuum
chamber to relieve it while rerolling, in order to prevent the pneumatics working by
the return of the sheet over the air-duct-bridge, which would play the music
backward with a jumble of discordant sounds. When the rerolling is completed the
handle is pushed back and raised, the motor then stops, and the movable bearing
returns to its normal position allowing vent-valve to close.
The action for operating the pedals in this instrument controls the expression
perfectly, which is, one of the most important features in any instrument, to which
attention will now be directed.
In this instrument it does not require a knowledge of music in order to play it
properly.
The expression action is operated as follows: When the music is made it is
provided with perforations where pedal-action is wanted, just the same as where a note
is to be sounded. When the perforation intended for expression passes its opening
in the air-duct-bridge, the bellows are operated similarly to that of the striking
bellows described.
The sustaining or damper operation is very similar to that of the regular striking
action, as the opening of the air-duct allows the bellows, S¹, to be drawn down, pulling
down lever, T', holding it the required time. The soft pedal bellows, S2, is operated
just the same as sustaining pedal, S¹, but has the addition of a catch or tripping
bar, W, lever, T³, and small bellows, S³.
The object of these parts is as follows:-
As the soft pedal needs to be kept down very often for a considerable length of
time, it would require a long continuous slot or hole in the sheet music to keep the
port open to hold the pedal down, but with the catch or trip-bar, W, a small hole in
the music passing the opening in the air-duct-bridge causes the bellows, S², to draw
down the levers, T2, until the end catches under top block, 62, on catch-bar, W, where
it is held as long as required. When the time comes to let up the pedal a perforation
in the music operates the small bellows, S³, releasing lever, T³, and allowing it to
return.
The first block, 62, on tripping-bar, W, is "soft" on piano and is operated as above
described. In case the music requires "very_soft." ("PP”) or "double piano" the
small bellows, S3, acts at the same time as the large one, S2, pulling back the catch-bar
and allowing the lever, T2, to be drawn down until it strikes the stop-block, Q. The
catch-bar returns instantly and holds the lever down under the lower block, 63, where
it is held until released by the small bellows, S³.
In case it is being held at "P P" ("very, soft") and wants to return to P,
("medium soft ") the small bellows gives a quick motion releasing the lever, but
returns in time to catch in next space, from which it may be returned again to PP
very soft," or released and returned to normal or, "loud," there being no limit if the
music is properly written. As before mentioned the small lifting bellows are of
peculiar construction, of which particular mention will be made.
"
Very fine leather is glued together so as to form a tube the desired length, as shown

page_text: in Fig. 18, and the ends of this tube are closed by flattening or pressing together
and giving them one fold back and gluing them. Then two very light, thin pieces
of wood are glued on opposite each other corresponding to the flattened sides of the
tube, in order that only one end of this bellows inay open. There is a small strip of
thin leather glued to the top piece of wood and passed over the end of tube and glued
to the bottom, this forms a kind of hinge, e, allowing only one end to open freely-
-as
shown in Fig. 17. To the top board (bottom as shown in Fig. 17) at the free end is
attached a pin, as, for the purpose of opening the check-valve, N, and immediately
back of said pin is a small hole or vent at a, Fig. 17. The air is admitted to said
bellows through an opening in the bottom, as shown at b, Fig. 17. This makes a very
light and sensitive bellows of more power than any other construction using so small
a space.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1 In an automatic piano-playing action, a key-striking device compactly arranged
to be placed beneath the keys, and within the piano-case, and comprising a set of
vertical lifting stems, a double series of elbow levers arranged alternately upon
opposite sides of the row of stems, a double series of vertically arranged striking
bellows operating on said levers, a double series of valves, pneumatics, and chambers,
arranged respectively, below the two series of striking bellows and a central support-
ing frame-work and central vertical tubes, connecting the valve-chamber to the
striking-bellows, substantially as and for the purposes specified.
2 In an automatic piano-playing action the combination of the two rails, F, F,
having flange-plates, f, f, and two corresponding series of elbow levers, G, pivoted to
said plates, vertical key lifting stems, P, supported upon the elbow-levers, the
vertically arranged frame-work, B, C, C, B, two series of vertical striking-bellows D, D,
arranged upon opposite sides of the frame-work to act upon elbow levers, G; and sub-
jacent valves, pneumatics, and air-tubes, substantially as and for the purposes
specified.
3-In an automatic piano-playing action, the combination of a generally vertical
frame-work comprising horizontal top and bottom rails, B, B, and horizontal inter-
mediate rails, C, C, striking-bellows arranged vertically upon the top rail, B, and
middle rails, C, valve mechanism and operating pneumatics arranged vertically upon
the middle rails, C, and lower rail, B, connecting tubes between the valve-mechanism
and the striking-bellows, said tubes being arranged centrally, a series of vertical
lifting stems for the piano-keys, and also for transmitting the motion of the striking-
bellows to the key-lifting stems, all being constructed to be placed within the piano-
case below the keys and invisible from without, substantially as and for the purposes
specified.
4 In an automatic piano-playing action, the combination with the key-striking-
bellows and the middle horizontal rails, C, C, and the bottom horizontal rail, B;
of the vertical valve-boards, E, having openings through them and provided with
bellows, chambers, I, and valve-cells, L, on opposite sides of said vertical board,
the lifting-bellows or pneumatics arranged in chamber, I, and communicating with.
tubes leading to the air-duct-bridge, the cell, L, being provided with a check-valve,
and additional valve, t, central and vertically arranged tubes leading to the striking-
bellows, said valves, valve-chambers, and bellows being duplicated upon opposite
sides of the central pipe and frame-work, substantially as and for the purposes
described.
5 A valve-mechanism comprising the horizontal fraine-rails, C, B, vertical valve-
board E, the bellows-casing, H, hollowed out and applied to the exterior of valve-
board, E, and having on its outer side tube connection, J, the valve-cells, L,
hollowed out and applied to the inside of the valve-board and having a connection N,
for the striking-bellows, tubes and valves and lifting bellows, substantially as and
for the purpose' described.

page_text: 6 The air-duct-bridge composed of a middle board, a¹, having its upper end
slotted, and two side boards, a³, and a³, on their sides adjacent to the middle
board and terminating short of the upper edge and communicating with the
slotted spaces of the middle board, said channels being all arranged to open at
their lower ends through one side of the ledge, substantially as and for the
purpose described.
7-A check-valve, M, for an automatic piano-player comprising a stiff back
piece and a loose flexible facing fastened only at its ends to the back piece and
sagging or hanging loosely, a valve-board with a hole in it, and a spring secured
to the valve-board and lying against the back of the valve, substantially as and
for the purposes specified.
8-In an automatic piano-playing device the combination with the pedal or
expression rods, of an operating bellows having check valve and lifting pneumatic,
a connecting lever, and a supplemental bellows with check-valve and pneumatic,
and a catch-lever for the suppleinental-bellows for catching and holding the lever
to the main expression bellows in either an extreme or intermediate position to
continue any expression without undue prointion of an opening in the paper
strip as set forth.
9 In an automatic piano-playing device, the combination with the air-duct-
bridge, and the two winding drums on opposite sides of the same; of the
longitudinally adjustable shaft 37, arranged parallel with and in rear of the drums
and carrying a rigid collar 38, in the middle, an adjustable friction-gear 36, 36,
at one end, and an elongated pinion 54, at the other, a train of gears connecting
the latter with the winding-drum, a loose pulley 45, with clutch, coupling the
same to the shaft 37, pulley 48, for the reroll-drum, B2, belt, 47, shifting slide 39,
embracing collar 38, elbow-crank 40, connected to said slide, and adjustable pull-rod
for the elbow-crank, substantially as and for the purposes described.
10 The combination with the speed-shifting device, of the jointed pull-rod 41,
and a pair of electrical contacts controlling an electric motor, said contacts being
operated upon by the outer end of the jointed pull-rod with a radial movement of the
same handle that operates the speed-shifting device, as shown and described.
11 The combination with the vacuum-chamber for the pneumatics, and rerolling
devices, of the shifting or reversing mechanism, a pull-rod operating the same, the
tilting bearing 42, with lug 43, the rocking crank-shaft 44, and the valve, z, for the
vacuum-chamber, arranged to be opened simultaneously with the operation of
the rerolling devices to relieve the vacuum and prevent playing the music backward
when rerolling the same, substantially as described.
12 The combination with the vacuum-chamber for the pneumatics, of the relief-
valve, z, crank-shaft 44, the movable bearing 42, binged at its lower end h², and
having an arm 43, arranged to be operated against the crank-shaft, and the pull-rod
for disconnecting the gears and re-winding the music sheet, said pull-rod being
arranged to tilt the movable bearing 42, rock the crank-shaft 44, and open the relief-
valve, substantially as described.
13 The lifter-bellows or "pneumatic" comprising a flexible tube, b, with
openings, a and b, rigid strips on opposite sides of the tubes connected together at
one end by hinge, e, and the pin, a³, fixed on one of the rigid strips and projecting
therefrom, substantially as and for the purposes described.
Dated this 10th day of January 1898.