Instruments having Finger Keys.
Year: 1885

page_text: Instruments having Finger Keys.
I, CHARLES DENTON ABEL of No. 28 Southampton Buildings in the County of
Middlesex, Consulting Engineer and Patent Agent, do hereby declare the nature
of my invention for "IMPROVED APPARATUS FOR PLAYING UPON PIANOS AND OTHER
MUSICAL INSTRUMENTS HAVING FINGER KEYS to be as follows:-
و"
This invention relates to an improved construction of that description of
apparatus for playing on pianos and other instruments having finger keys wherein
a series of mechanical fingers or strikers situated over the finger keys are actuated
by a travelling perforated music card operating in combination with mechanism so
as to depress the finger keys as in playing with the hands. The main feature of
the present invention consists in effecting the movement of the strikers by means
of a cord or band, one end of which is attached to a lever actuating the striker,
which cord after being passed round one or more barrels or cylinders to which
continuous rotary motion is imparted, has its other end subjected to a pull of
greater or less force, whereby the cord being more or less tightened upon the barrel
will be made to exert a variable pull with its other end upon the striker lever, so
that the striker will be actuated with more or less force and thus produce the effect
of expression in playing.
j
According to the arrangement employed by preference for this purpose, there are
three barrels geared together, one of which is rotated by a crank handle and
imparts motion to the other two in the contrary direction. These barrels have as
many circular grooves in them as there are keys of the piano, and situated below
the barrels are a number of bars capable of sliding longitudinally, each bar being
situated in one of the grooves. To each bar is attached one end of a cord or band,
which is first led round in the groove of one of the driven barrels, then round the
groove of the driving barrel, whence it passes to a sliding piece which is connected
Price Qi

page_text: by a rod with screw adjustment to an elbow lever that actuates the striker. The
sliding bar is connected by a rod or cord to the one arm of an elbow lever having
an angular beak that is caused by a spring pusher acting on the other arm of the
lever to press upwards against the under surface of the travelling music-card, this
being held against such upward pressure by a grooved roller on its upper surface.
"reader,"
Thus when a perforation of the card passes the beak of the lever or
this is moved upward through the perforation by the spring pusher, and is thereby
made to pull upward the sliding bar so as to bring it more or less forcibly in
contact with the third grooved barrel, the rotation of which consequently induces a
longitudinal motion of the bar, and a corresponding pull upon the cord that
actuates the striker. By varying the degree of upward pull upon the sliding bar,
its contact with the barrel will be made more or less forcible resulting in a corre-
sponding variation of the force with which the striker strikes the finger key. This
variation is obtained by pivotting the spring pusher at its one end so that its other
end can be made to act at different points of the arm of the "reader" at greater or
less distance from the fulcrum thereby varying the motion which it imparts to the
"reader." The pusher is actuated for this purpose by a slide moved by hand and
either the whole of the pushers may be actuated by a single slide whereby the
expression of the whole of the notes will be varied at the same time, or the pushers
may be connected in independent groups to two or more hand slides, so that the
expression of the corresponding groups of notes can be varied independently of the
others.
The variation of the expression may also be obtained in other ways, such as by
varying the position of end stops that limit the longitudinal motion of the sliding
bars, or by varying the speed of rotation of the actuating barrels.
As is well known, sustained notes are obtained by forming long slots in tho
music card so that the striker is kept continuously depressed for the requisite
Jength of time. As, however, such slots, when of excessive length, weaken the
music card, they are according to the present invention strengthened at intervals
by narrow cross pieces and in order to prevent these cross pieces from having the
effect of interrupting the note, the sliding bar is maintained in the strained position
while the cross-pieces are passing the "reader," by means of a catch actuated by a
second "reader" lever whose beak is make to enter a special lino of perforations
formed in the card at points corresponding to the positions of the cross pieces.
The sliding bars rest upon small rollers that have rotary motion imparted to
them in the contrary direction of that of the barrels, so that when the bar ceases to
be engaged with the barrel, it is brought back to its original position by the said
rollers.
The strikers consist by preference of a rod sliding vertically in a guide bar and
having at its upper and lower ends metal sockets into which are screwed leather
plugs, the lower one of which strikes the key while the upper one has the actuating
lever bearing upon it.
The rod passes through a helical spring that brings it into the raised position
away from the key when it is not actuated.
A flannel washer is provided between the striker head and the guide bar to
prevent noise in coming in contact.
The rod connecting the actuating lever to the slide to which the pulling cord is
attached can be unhooked and adjusted in length by screwing so as to adjust the
tension of the cord.
In place of communicating the movement of the "reader" lever that is in
contact with the music-card directly to the sliding bar by means of a rod as
described, the music-card and "reader" may be situated at a distance from the
piano where the other part of the mechanism is situated. For this purpose, the rod
of the sliding bar is connected to the armature of a small electro-magnet, the coil of
which is included in the circuit of an electric battery, in which is also included the
"reador" at a distance. This consists of an insulated spring arm, having a beak
bearing upon the music card and so arranged that when it enters a passing

page_text: perforation, it makes an electrical contact, closing the circuit and actuating the
electromagnet, the armature of which in its turn actuates the sliding bar.
Or, instead of actuating the apparatus by an electric current the reader lever
may be connected to a piston or other device for conveying air pressure through a
tube to a second piston connected to a lover that actuates the sliding rod in a
similar manner to that employed for pneumatic bells.
Instruments having Finger Keys.
I, CHARLES DENTON ABEL, of No 28 Southampton Buildings, Chancery Lane
in the County of Middlesex, Consulting Engineer and Patent Agent, 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:-
This invention relates to an improved construction of that description of apparatus
for playing on pianos and other instruments having finger keys wherein a series
of mechanical fingers or strikers situated over the finger keys are actuated by
a travelling perforated music card operating in combination with mechanism so as
to depress the finger keys as in playing with the hands. The main feature of
the present invention consists in effecting the movement of the strikers by means
of a cord or band, one end of which is attached to a lever actuating the striker,
which cord, after being passed round one or more drums or cylinders to which
continuous rotary motion is imparted, has its other end subjected to a pull of
greater or less force, whereby the cord, being more or less tightened upon the drum,
will be made to exert a variable pull with its other end upon the striker lever, so
that the striker will be actuated with more or less force, and thus produco the
effect of "expression" in playing.
The arrangement of apparatus employed by preference for carrying out this
invention is shewn on the accompanying drawings in which Fig. 1 shews a longi-
tudinal vertical section, Fig. 2 a cross section and Fig. 3 a sectional plan. The
apparatus consists of three revolving drums or cylinders A B C, each having fixed
thereto a toothed wheel a bc which are geared together so that the drums A and C
revolve in the same direction while B revolves in the contrary direction and receives
its motion through a crank-handle M fixed on the axis thereof. The length of these
51

page_text: drums varies according to the number of keys of the instrument to be played upon.
As the mechanisms that act on the different keys are all identical one with the
other, it will be sufficient to describe a single one thereof.
A small wooden bar a moves to and fro between fixed stops z z¹ in grooves b² 6*
formed in the supports D in which the bar rests freely. This bar can move to and
fro below the drums A and C, working in the grooves c d thereof.
The groove c
of the drum A is so formed that when the bar is raised into it, it will be carried
along by the friction in the groove on the rotation of the drum. The groove d of
the drum C is made narrower at bottom in order that the friction between it and
the cord e, which surrounds the greater part thereof, may be increased sufficiently
to produce an effective pull thereon when the drum revolves. The said cord also
passes round the drum B and has its end attached to a bar E sliding in a guide F.
It is this bar E which actuates, at the desired moment, the striker P, this being
effected by the following means:
On the upper end of the striker bears the end f of the arm g fixed on the
underside of the pivotted cross bar G. Upon the top of this is fixed a metal pin h
to which is attached the rod i that hooks into the end of the sliding bar E. The
connection between h and i is effected by means of a horizontal stud into which is
screwed the end of the rod ; thus, on unhooking the rod i from the bar E and
turning it in one direction or the other, its length may be regulated to the required
degree so as to apply a greater or less amount of tension to the cord e. In place of
a cord might be used, in some cases, a wire or a strip of iron, steel or brass. The
striker is constructed of a leather plug k screwed into a copper block p attached to
a rod to the other end of which is screwed a second block p' also containing a
leather plug. A spring m tends to draw the striker upwards again when it is
released from the arm g after being depressed thereby. A felt washer n prevents
occurrence of noise on the striker coming in contact with the framing in its upward
motion. The travelling music card X, suitably perforated, is made to pass between
the rollers R R covered with caoutchouc one of which receives rotary motion from
the crank handle by means of toothed gearing op q. The music card passes over
the board H beneath the metallic roller I provided with as many grooves r as there
are mechanisms for acting upon the finger keys so that each groove, as also each
longitudinal line of perforations, corresponds to a note. Each mechanism also
includes an elbow lever K pivotted at 8, of which the upper, horizontal arm carries
a beak t which engages in a corresponding groover of the metal roller. This
horizontal arm is connected to the bar a by means of a metal wire or cord u which
hooks on to another coiled wire u³ fixed to the bar a by having its bent end inserted
into a hole in the latter. The vertical arm of the lever K is always acted upon by
a spring O so that the beak t always has a tendency to rise; the spring O surrounds
a small rod or pusher x. Its one end bears against the support Z while its other
end is fixed to the end y of the pusher so as by its action to tend to draw the
pusher forward so that the pusher exerts a continual pressure upon the vertical
arm of the lever K.
When the music card in travelling presents a full portion to the beak t this is
depressed and consequently compresses the spring O. As soon as a perforation
presents itself the beak t passes through the same by the action of the spring thus
applying a pull upon the wire u whereby the bar a is drawn up in contact with
the drum A, the rotation of which imparts a longitudinal motion thereto. The
bar a having the cord e attached to it thus exercises a pull upon the latter so as to
tighten it round the drums C and B, the rotation of which cousequently apply an
increased pull upon the upper end of the cord c, causing it to act with sufficient
force upon the transverse bar G which is thus made to depress the striker P, and
thus to actuate the finger key of the piano beneath it. As soon as the beak t of
the lever K. passes on to a full portion of the music card, the bar a is released
and, in falling, moves away from the drum A and, in thus ceasing to have any
pull exerted upon it, it also releases the cord e, whereupon the spring of the
striker will lift this into the raised position again. The longitudinal movement of

page_text: the bar a is limited by the stop z; this stop might be dispensed with, a sufficient
stop being afforded by the depression of the finger key, but in this case a useless
expenditure of power would be caused by frictional contact between the cord and
the drums for overcoming the counter pressure of the springs.
It will be seen from the foregoing description that the energy of the contacts
and consequently the strength of blow received by the finger keys depend upon
the power with which the bar a is applied to the drums. It results from this
that, for modifying the force with which each note is struck and thus giving
what is known as "expression," it will suffice to cause the wire u to have a greater
or less lifting force. This result is obtained by modifying, at will, the action of the
pressure exerted by the spring O upon the elbow lever H. This action is varied,
not by varying the force of the spring O but by varying, at will, the point at which
the spring acts upon the vertical arm of the lever K. For this purpose the
supports Z Z that carry the pusher c actuated by the spring O form part of a
frame that can be raised or lowered upon the axis y'. This is effected by means
of the bar a provided externally with a button 61. The upward or downward
movement of the frame with the pushers is easily effected, as it takes place in a
direction at right angles to the pressure of the springs. Other means might be
employed for varying the force with which the strikers act upon the finger keys.
Thus, for instance, it may be effected by varying the speed of rotation of the
cylinders, or again, the motion of the bars a might be controlled by movable
stops.
In the above described arrangement which is adopted by preference, all the
springs acting upon the levers K can be mounted on one and the same pivotted
framing which may be termed "expression board." In this case the springs will
consequently all be moved relatively to the levers K to the same amount.
Practically it would certainly be advantageous to divide them into two sets, one
set corresponding with the treble notes and the other with the base notes, in which
case each set would be mounted on a separate expression board having a separate
finger stop so that the expression of the base and treble could be varied indepen-
dently of each other. If desired also a still greater subdivision of the expression
boards may be employed.
In order to ensure the return of the bars a into their original position when they
cease to be acted upon by the wire u, there are arranged under the drums A and C
small rollers that are provided with circular grooves like those of the drums.
These rollers have their axes connected by toothed gearing c d e¹ c² d² e³ with the
axes of the drums A and C so that the upper part of these rollers move in the
contrary direction to the lower part of the drums A and C. From this it follows
that as soon as the bars a are liberated and come in contact with the rollers ³ these
move them back at once into their original position. It will be understood that in
order to sustain a note for any length of time it is sufficient to increase the length
of the perforation in the music card to the required extent, but by this means the
music card is reduced in strength. In order to obviate this inconvenience the
following arrangement is employed.
Instead of making a continuous long slot in the card this slot is connected at
certain distances apart by transverse pieces of the card; but as these transverse
pieces would cause an interruption in the note, such cessation of the sound is
prevented by means of a pedal catch p¹ pivotted at ¹ and connected by a wire q¹
to a supplemental elbow lever K', the beak of which is situated opposite a supple-
mental line I on the music card as shewn in plan at Fig. 4. This line presents
perforations o¹ situated exactly opposite the strengthening bars of the long slot
above mentioned, the perforations o¹ being at least of the same length as the
strengthening bars l. The bars a have on their underside triangular notches ffs
and the pedal catch p¹ has a triangular tooth g¹ extending across the whole width of
the apparatus. Whenever an opening o' of the line I passes over the beak of the
lever K', the 'catch p¹ is raised and causing the tooth g¹ to enter the notches of the
.

page_text: corresponding bars a and thus holds this or these in the position in which it or they
cause the finger key to be depresserl, as although during this time the lever K, will
be depressed by the transverse bar 7 the consequent releasing of the bar a thereby
will not cause this to move back into its original position as it is held by the catch.
It will be understood that the perforations o¹ and strengthening bars 7 must bo
made in such positions as not to interfere with the action of the perforations in
any of the other lines of notes. It is not necessary that the above described
apparatus with its music card should be fixed to the other part of the apparatus.
It may be arranged independently thereof and may even be situated at a distance
"therefrom, in which case its action would be transmitted to the striking apparatus
by means of pneumatic or electric transmission.
An arrangement for this purpose is shewn at Figs. 5 and 6. In this case all the
elbow levers K and their support are dispensed with, and are replaced by small flat
electromagnets h of which the armatures k¹ are connected by rods u¹ to the bars a
so as by their motion to raise and lower the latter. A current of greater or less
duration is conveyed through the coil of one or other of these electromagnets h¹, by
means of the reading apparatus at Fig. 6. This consists of a table over which
passes the music card beneath which are arranged as many springs 8¹ as there are
notes. All the springs are attached to a transverse bar m³ formed of insulating
material and each one is connected on the one hand with the corresponding electro-
magnet while, on the other hand, it is provided with a stud n' which is situated
above a metal plate 9' which is common to all the springs. This plate q' com-
municates with one pole of a battery, the other pole of which is connected to all
the electromagnets. This electrical reading apparatus presents great advantages
over similar apparatus beretofore employed. The perforations in the music card
always remain very accurate in shape and the contact which is formed indepen-
dently of the music card between the atud n' and the plate q¹ is absolutely certain.
Owing to its small size the above described apparatus can be placed over the key
board of an apparatus and it is therefore much less cumbersome than the so-called
pianista" over which it possesses the further advantage of permitting of great
variation of "expression." Any description of music card may be employed in
connection with this apparatus, whether of strong paper, card-board, woven fabric,
wood or metal, and the perforations may, in certain cases, be replaced by studs or
projections of various kinds.
"
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 is
1. In apparatus for playing upon pianos and the like, the method of imparting
motion to the strikers by the pull produced by the frictional contact of a cord upon
a revolving drum or cylinder, such contact being regulated according to the strength
of stroke required, and made to cease when the action of the striker is to be dis-
continued, substantially as herein described.
2. In the method of operating the strikers referred to in the preceding claim, the
use of two or more grooved drums or cylinders round which the operating cord is
wound in order to increase the force of its pull by increasing the frictional contact,
substantially as herein described.
3. The herein described mechanism for carrying out the method of operating the
strikers referred to in the preceding claims, consisting of a sliding bar which by the
action of the music card upon a lever is brought into frictional contact with a
revolving drum and in thus having longitudinal motion imparted to it, draws the
operating cord of the strikers into frictional contact with one or more other
revolving drums.
4. The arrangement whereby the springs operating the levers that actuate the
sliding bars referred to in the preceding claim, can be made to act upon such levers
at different points of their fulcra in order to vary the force with which the sliding
bars and cords act upon the strikers, and thus to produce "expression."

page_text: 5. The use in combination with the sliding bars a, of rollers for bringing
back the bars into their original position, substantially as herein described.
6. The use in combination with the sliding bars a of the retaining catch or pedal
lever pl with tooth g¹ acted upon by a supplemental lever K₁ and wire q' whereby
the action of the bar a upon the striker is maintained while the transverse
strengthening pieces of the slots I' in the music card depress the lever K
substantially as herein described.
7. The general arrangement and combination of parts herein described with
reference to Figs. 1, 2 and 3 of the drawings constituting apparatus for playing
upon pianos and the like.
8. The arrangement herein described with reference to Figs. 5 and 6 wherein
the mechanism that is operated by the music card is separate from the mechanism
that actuates the strikers, motion being communicated from the former to the
latter by means of an electric current or by other suitable means.
ABEL & IMRAY,
Agents for the Applicant.