Improvements in Apparatus for Facilitating the Teaching of the Piano.
Year: 1892

page_text: Date of Application, 19th July, 1892-Accepted, 3rd Sept., 1892
COMPLETE SPECIFICATION.
[Communicated from abroad by ALMON KINCAID VIRGIL, of 26, West 15th
Street, New York City, State of New York, United States of America,
Musician.]
Improvements in Apparatus for Facilitating the Teaching of the
Piano.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co., Patent
Agents, 45 Southampton Buildings in the County of Middlesex, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement :-
This invention has for its object the instruction of pupils on the piano. It is
embodied in an instrument containing a facsimile of the piano key-board but in lieu
of the piano movements for producing musical tones, mechanism is combined with
the keys of this instrument whereby a click or short quick sound resembling that of
a telegraph key, is produced at the termination of the downward and upward stroke
of each key, respectively and also mechanism whereby the touch of the keys is
assimilated to that of the piano. The mechanism for producing the down clicks and
the up clicks, respectively are so constructed that either or both may be thrown out
of operation.
The point at which the down clicks occur is made to correspond with the point in
the travel of the key of the piano at which the musical tone commences because,
although in the piano the hammer is thrown against the string before the key is
fully depressed, yet the tone does not commence until after the hammer has left the
string or just about the instant when the key is fully down on its cushion. The
point at which the up clicks occur is made to correspond with the point at which in
à piano, the musical tone ceases because, although the damper of a piano comes
upon the string slightly before the key is fully elevated, yet the vibration of the
string and the sound caused thereby are not fully destroyed until the damper has
rested upon the string for an instant, which continues to about the instant when the
key is fully elevated.
The instrument is shown in the accompanying drawings in which
Figure 1 is a plan view thereof having the upper portion of the case removed and
having certain of the other parts omitted at one end to display the interior
construction.
Figure 2 is a section taken longitudinally through one of the keys showing the
key in its depressed position.
Figure 3 is a similar section showing the key in its raised position.
Figures 4 and 5 are details of the mechanism for adjusting the click producing
devices into and out of operation.
Figure 6 is a front view of the name board showing the tension indicator.
Figure 7 is a sectional elevation of a modification.
The white keys are lettered a and the black keys are lettered b. These keys are
constructed like those in an ordinary piano and are arranged and controlled in
position by a series of balance or fulcrum pins lettered respectively a b. They
rest upon the balance rail c extending under all the keys and are also furnished
with the guide pins d extending upward from the piece e arranged transversely
under all the keys. The rear ends of the keys are so weighted by weights fat
their extremities remote from the finger ends, that the rear ends slightly over-
balance the front ends, so that the said keys normally assume the position shown in
Figure 3. Underneath the keys at the rear end, extends transversely, the piece g.
Cushions are arranged under the forward ends of the keys, and cushions under

page_text: the rear ends thereof.
Each key is provided with a downwardly projecting
metallic spur under its forward end and a corresponding spur i under its rear end,
and these spurs are screw-threaded into the key so that they may be adjusted to
project a greater or less distance from the surface of the key. Beneath the series
of spurs is arranged transversely of the keys, a hard platej which is fitted into a
slot in a bark, being packed in said slot by felt or other compressible material
whereby vibration and rattling are prevented. is a hard plate extending
transversely of the keys under the series of spurs and which is also packed within
a slot of the bar k.
It is essential that the bars and carrying the plates and should be
adjustable, vertically, and to that end I provide such mechanism as is shown in
Figure 4. The bar is stationary in a longitudinal direction; but below it is a
bar which is movable longitudinally, and still below that is an incline m which is
stationary. I and m are provided with inverse inclines o and p so that when the
bar is shoved longitudinally toward the left of Figure 4, it will be raised vertically
by the action of such inclines into the position shown in that figure; whereas, when
it is moved toward the right of Figure 4 it will fall vertically. Such longitudinal
movements are imparted by the lever fulcrummed to the case having a handler,
in any suitable position. The bar & is held in position and guided vertically by a
series of studs s. A similar arrangement is provided for raising and lowering the
bar the same being illustrated in Figures 3 and 5.
The parts for controlling the vertical position of the bar are moved
longitudinally by a lever which takes the bent form shown in Figure 5 in order
to extend from the rear position of the bar to the convenient front position of the
handle.
Now, it will be understood that the mechanism above described will afford
perfect control of the vertical positions of the plates and and not only 50, but
will support and control them in any position which they may occupy so that they
will be held firmly and without any substantial tendency to rattle.
The extent of vertical adjustment of the plates; and is regulated in accordance
with the adjustment of the spurs and and the position of the cushions and W.
When these parts, however, are in proper relative position and adjustment, the key
in its descent at either end will strike and commence to compress the cushion / or
as the case may be, before the spur or as the case may be, comes in contact with
the plate or so that a certain amount of power is required to compress the
cushion, especially under the forward end of the key before the spur will strike the
plate. In constructing the machine, this power is regulated to a nicety by adjusting
the spur in each of the keys until the same power is required for all the keys in
compressing the cushion sufficiently to bring the spurs into contact with the
plates.
This operation of compressing the cushions is an important feature in the
machine, because by virtue of it, the strength of touch is insured to the full end of
the stroke and as soon as the touch is released the resilience of the cushion at once
raises the key sufficiently to break the contact between the spur and the plate and
thus prevent any rattling.
The
It remains to describe the mechanism whereby the key resistance is determined
and the character of the touch is still further controlled. Over the back end of
each key is located a vertically movable weight t in such position as to be struck by
the upward movement of the rear end of the key and to be thrown by its momentum
above the key so as to drop back upon the key and cause a back stroke.
springs by which the key resistance is principally produced are lettered ", being
coil springs mounted upon the tops of the keys. These coil springs are extended
into the upward projecting spring arms u¹ which bear against a bar u extending
clear across the instrument. The rear ends of the keys cannot rise so as to
approach the bar without causing the compression of the springs but the extent
of this compression is varied by the adjustment of the bar upon the screw shaft e
which extends out through the name board of the instrument and is provided with

page_text: the handle By turning this screw shaft in one direction, the bar is moved
toward the back of the instrument and by turning the screw shaft in the opposite
direction, the bar is moved toward the front of the instrument; in the first case
producing greater compression of the springs and in the latter case, less. The
spring arms are, however, so formed as shown in the drawings, and the surface
of the bar against which these spring arms act is so formed, that while the tension
of the spring tends to force the rear end of the key downward, the friction between
the spring arm and the surface of the bar v caused by the sliding of such spring
arm on the surface of the bar is in a direction opposed to either the downward or
the upward motion of the rear end of the key. Thus, the sensible action and
reaction of the springs upon the keys is deadened.
It is very important that the screw shaft should move the bar squarely, and
to this end an additional bearing is provided for the screw shaft which is braced
In order that the
to the bar in both directions by the braces w¹ and w².
flexible
adjustment of the screw shaft may be indicated, I connect it by a
connection with an index finger which is pulled in the opposite direction by a
spring This index finger extends out through a slot in the name board, as
shown in Figure 6, and moves adjacent to a scale placed on the name board. A
series of springs lettered y extend rearward from a fixed bar y and rest upon the
rear of the keys adjacent to the spurs the tendency of these springs being to
press downward the rear extremities of the keys, but these springs are very weak in
comparison with those before described.
The operation of the instrument is as follows:-Starting with the keys in their
normal position, as shown in Figure 3, the first thing to do is to adjust the
instrument by means of the screw threads on the spurs i and so that they will
strike the plates and j¹ after the cushions have been compressed, when (if it is
desired to produce a click both at the down stroke and up stroke of the keys) the
bars and are adjusted to their uppermost positions. When one key is depressed
it will press the cushion beneath it and then the spur i will strike against the
plate so as to give a sharp distinct sound commencing and occurring the moment
when the key is down, and immediately the expansive force of the cushion will
raise the key so as to break the contact between the spur and the plate j. When
now, the key is released by the finger, it will return to its normal position shown in
Figure 3, but the momentum that it acquired in making the movement will cause
the rear end of the key to compress the cushion / sufficiently to permit the spur
to strike the plate j and produce a click which commences and occurs when the
key is up. The momentum of the key being exhausted the expansive force of the
cushion will immediately break the connection between the spur and the plate.
In the modification shown in Figure 7, the principal difference consists in the
manner of supporting the click producing devices which in this case, are
respectively supported upon rotatable bars 13 by the rotation of which either of
the plates may be removed from the position shown in full lines in Figure 7,
where they will not be struck by the spurs to the position shown in dotted lines
in Figure 7 where they will be struck by those spurs.
When the keys are operated under a normal tension of say two ounces, the bar
will be adjusted so far forward that the spring arms will not exert pressure at
any position of the keys, the tension being then dependent upon the weight and the
spring y. The
pressure between the spring arms and the bar occurs when the
bar is adjusted back to produce a tension exceeding, say, three ounces.
In employing this instrument for instruction, the up-clicks will be thrown into
operation until the pupil has become accustomed to release the keys properly.
Then the down-clicks will be brought into operation with the up-clicks, and the
pupil will practice the down and up action of the fingers until he has become
equally accurate and prompt in depressing and releasing the keys. Next, with
both the down and up-clicks in action, the pupil will practice to release one key and
simultaneously to depress another key until he has acquired the skill to cause the
up-click of a released key and the down-click of a depressed key to so coalesce as

page_text: to produce only one sound; thus is produced the perfect legato. All of the various
qualities of piano touch should be practiced with the down and up-clicks in action.
Any incorrect finger movements will at once be. announced by the clicks. After
the fingers have been so trained, the pupil will be, able to play accurately, any
music upon the instrument, and without further practice to play on the piano.
When the pupil is practicing musical compositions on the instrument, the down
clicks should be used without the up-clicks. The up-clicks and the up and down-
clicks in combination, will be used only in technic practice, and in the practice of
passages in musical compositions to test the accuracy of the touch.
Having now particularly described and ascertained the nature of this invention
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. The combination with a key board, of a device to produce a short quick sound
occurring when a key is down.
2. The combination with a key board, of a device to produce a short quick sound
occurring when a key is up.
3. The combination with either of the above of means whereby the sounder may
be thrown out of operation.
4. The combination with a key board, of sounders and cushions compressed
simultaneously with the striking of the sounders.
5. The combination with a key board and sounders of inclined sliding surfaces
whereby the sounders may be raised or lowered.
6. The combination with a key board, of an adjustable bar and a spring arm
interposed between said bar and cach key and extending approximately in the
direction of motion of the key, whereby as the key moves the friction produced by
the sliding contact of said spring arm is in a direction opposed to the action or
reaction of said spring.
7. The combination with a key board, of an adjustable bar, a screw shaft
extending through the name board and connecting with said bar and a spring
interposed between said bar and each key.
8. The combination with the last of a scale on the name board and a tension
indicator finger.
Dated this 19th day of July 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.