IMPROVEMENTS IN PIANOS, ORGANS OR OTHER MUSICAL INSTRUMENTS HAVING KEYBOARDS
Year: 1883

page_text: "
LETTERS PATENT to John Henry Johnson of 47 Lincolns Inn Fields, in the
County of Middlesex, Gentleman for an Invention of "IMPROVEMENTS IN
PIANOS, ORGANS OR OTHER MUSICAL INSTRUMENTS HAVING KEYBOARDS
communicated to him from Walter Richard Elmenhorst, of the City of
Montreal in the District of Montreal, and Province of Quebec, Canada,
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents on the 31st October 1883.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman "IMPROVEMENTS IN PIANOS [ORGANS] OR OTHER MUSICAL INSTRUMENTS
HAVING KEY BOARDS" A communication to me from Walter Richard Elmenhorst
of the City of Montreal in the District of Montreal and Province of Quebec
Canada
The object of this Invention is to supply mechanical means whereby an air or
melody played upon a Piano or Organ or analogous instrument may be transposed
from the original to a higher or lower key without diffulty, the air being played
in such higher or lower key while the player strikes apparently the notes set
down in the original music. The invention is applicable to all kinds of pianos and
organs.
This transposition key board may be described as consisting of two parts, one
the stationary frame, so called, not because it is permanently affixed to the piano
but in contradistinction to the sliding frame which it carries.
This stationary frame, which, when in place, occupies the whole space of the
keyboard of the instrument to which it is applied, carries in its two ends
longitudinal guides along which slides the upper frame to be presently described.
Besides these the ends of this frame carry a bar in which are suspended pins or
bolts corresponding to the keys of the keyboard of the piano.
These when the frame is in placo, rest respectively on the centres of such keys,
and when it is lifted off hang from the bar, to which they are attached usually by
pins working in slots formed in them.

page_text: The upper side of this bar will always be an even horizontal surface and the
heads of the pins or bolts be at the same level so that these must be of unequal
length according as they rest on the white or black keys of the key board.
The sliding frame is of course of less length than the stationary frame and is
composed of two ends carrying guide bars or slides corresponding to and moving 5
on the guides of the stationary frame.
To the rear one of these guide bars are secured pieces to which are attached the
several keys forming the bank carried by the sliding frame, springs assisting in
holding them up.
In the underside of the keys in the sliding frame are set immediately over the 1
line of the bar and the pins or bolts carried therein pins projecting downwards
sufficiently to clear the upper side of such bar when the sliding frame is moved
along.
The operation of the invention is very simple the stationary frame is set in
place on the key-board and the sliding frame brought to its normal position thereon 1
this being marked by the coincidence of the indicator on the front piece carried in
the stationary frame and the centre of the sliding frame which is then moved in
either direction, the desired distance, or number of semitonos which is shown by
an index or scale.
In any of these positions the pins projecting down from the keys of the sliding
frame are immediately and directly above the transmitting pins or bolts carried in
the stationary frame and resting on the respoctive keys of the key-board so that
when the air as originally set is played upon the bank of keys in the sliding frame
such keys when struck act through the transmitting pins or bolts and will reproduco
the air transposed as desired.
In order to secure the exact correspondence and working together of the soveral
parts it is proposed to so construct the ends of the stationary frame that the height
of the several bars & above the keyboard shall be adjustable and still further that
the exact position vertically of the bar carrying the transmitting bolts or pins
shall be adjustable in the ends of the frame.
The transmitting pins themselves are made in two parts connected by a screw so
as to be capable of adjustment in length and the pins which act on these from the
keys in the sliding frame can also be screwed in or drawn out at will.
This adjustment will probably only be needed when the transposition keyboard
is first applied to the piano or to take up subsequent wear, but to facilitate such 3
adjustment it is proposed to secure the rear guide bar of the sliding frame by
gudgeons or pivots to the rear guide of the stationary frame so that the former can
be thrown back and the parts adjusted without in most cases the necessity of
removing the transposition keyboard from the piano.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Patent Office on the 30th April 1884.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman "IMPROVEMENTS IN PIANOS ORGANS OR OTHER MUSICAL INSTRUMENTS
HAVING KEY BOARDS" a communication to me from Walter Richard Elmenhorst
of the City of Montreal in the district of Montreal and Province of Quebec,
Canada
The object of this Invention is to provide mechanical means whereby an air or
melody to be played upon a piano or analogous instrument may be transposed
from the original key to another key without difficulty so that such air or melody
may be played in such other key whilst the player strikes the same digitals that
he would use in playing the air or melody in the key set down in the original
music. The invention is applicable to all kinds of pianos or organs or analogous
instruments having keyboards without necessitating alterations in the key board of
the instrument. This transposition key board which is applied to the instrument
to effect this purpose may be briefly described as consisting Firstly of a frame
(which may be called the rigid or stationary frame) which is set over the key
board of the instrument or the lovers or parts by which the notes are caused to
sound and can be arranged to be instantaneously lifted off or put in placo without
any fastening being needed. In this frame is carried a bar in which are suspended
or contained pins or bolts or plungers which may if necessary be of different lengths
corresponding in number and position to the keys lovers or equivalent operating
parts of the instrument when the frame is in place resting upon such keys or parts.
In the ends of this stationary frame are also carried guido bars along and upon
which slides a framo carrying a bench of keys or digitals so that the position of
these keys relatively to the pins or bolts carried in the bar in the stationary frame
and consequently to the key board proper or operating levers or parts may be
varied at will. The stationary and sliding frames are so connected that the latter
can be turned back for the adjustment of the parts.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 is a plan view of the transposition key board in position as applied to
the ordinary key board of a piano or organ or the like. Figure 2 a part longitudinal
vertical section taken on the line 1, 1 Figure 1. Figure 3 a transverse section
taken on the line 2-2. Figure 1. Figure 4 a transverse section taken on the
line 3. 3. Figure 1. Figure 5 is an end view. Figure 6 is a part plan view of
underside of the transposition key board. and Figure 7 a detail of one of the bolts
pins or plungers. Figures 2 to 6 are drawn to a larger scale than that to which
Figure 1 is drawn and Figure 7 is drawn to a still larger scale.
The stationary frame is composed of the two ends A A connected by a bar D
(constructed as hereinafter described) and by bars B, B¹ and B' these having
projections on their upper surfaces and serving as ways for the sliding frame to
move upon. The bars B, B', are carried rigidly in the ends A A and the bar B' is
secured to the said ends A by gudgeons or pivot pins b for the purpose hereinafter
to be described. O is the front piece secured to the ends A A and having a cap
or strip O covered if desired to match the keys and upon this is marked a scale
indicating the relative positions of the sliding and stationary key boards. The
stationary frame above described covers the whole of the key board or operating

page_text: parts of the instrument to which it is applied resting on the first and last keys or
operating parts.
The bar D is perforated to hold the pins bolts or plungers E shewn in Figures
2, 3, 6 and 7 which correspond to the keys or operating levers or parts of the
instrument and are so placed as to be over their respective centres. These pins
bolts or plungers are preferably made in two parts connected by a screw E¹ (see
Figures 2, 3 and 7) so as to allow of adjustment in length and may be muffled on
their upper and lower surfaces with either felt, cork or rubber, or any other suitable
material. When the transposition key board is in place on the instrument these
pins bolts or plungers E rest on the surface of the keys or operating lovers
or parts, but they may be held in position by pins F passing through the bar D
and entering slots e in the plungers or in any other suitable way so that when the
transposition key board is removed the plungers are retained in position.
In the case illustrated by the drawing the bar D is shewn with its under surface
corresponding in outline to the black and white keys of the instrument and the
pins É are of two different lengths according as their positions are on white or
black keys. At the top of the bar D the heads of the plungers are in one plane
to allow the sliding frame to move easily along the bar and at the same time to
ensure the certain action of the keys or digitals (presently to be described) of the
Bliding frame.
The bar D may however be made with even and straight under surface the
pins or bolts for the white keys (when used with an ordinary key board beneath)
only projecting below it; but it must be understood that in all cases when the
frame is in position the tops of the pins bolts or plungers E are all in the same
plane.
G, G, are the ends of the sliding frame to which are secured guide pieces or
longitudinal bars H, H and H corresponding to and moving upon the ways B, B¹,
and B. Upon the upper surface of the bar H rest the rear ends of the keys or
digitals K, K which aro held up by springs L under each and have small front
lips k which take under the cap or strip C. In the rear of the keys K are
pieces G which are secured to the bar H2 and serve to retain the keys or digitals
in position which is also regulated by the pins h h' projecting up from the
bars HH and acting respectively on the white and black keys or digitals.
Pins K¹ (projecting downwards from the under surfaces of the keys or digitals K)
when the digitals are struck act upon the keys or operating levers or parts of the
instrument through the transmitting pins or bolts E but are not normally in contact
with them.
It will be seen that by sliding the frame in which the keys or digitals K are
carried along the stationary frame these keys or digitals can be brought over a
higher or lower part of the register of the keyboard or operating levers or parts of
the instrument, tho pins K¹ being sufficiently distant from the top of the bar D as
not to touch it while the frame is moved along and at the same time so close that
the slightest touch on the keys or digitals K will be communicated through the
transmitting pins E to the key board or operating levers or parts of the instrument
and that therefore by playing on the keys or digitals K K (when the sliding frame
is moved in either direction from the centre) the music as set down in the score,
its transposition to a higher or lower key will be effected, the difference in tone
being adjusted by means of the indicator placed on C' and the mark denoting the
centre of the keys or digitals K K, the divisions usually answering to semi-tones.
I have already stated that the pins E are made adjustable in length, the pins K
being also susceptible of similar adjustment by sorowing them into the keys and
in addition to this it is proposed to render the Invention still more applicable to
different kinds of instruments by constructing the ends of the stationary frame
Eo as to bo adjustable in height by means of set screws a a working in blocks a¹ a
muffled or cushioned at the bottom upon which the ends rost, the bar D being
also secured to the ends AA by set screws working in a slot so that its height with
relation to these ends can be easily and readily adjusted.

page_text: The sliding frame with the bar B₁ can be turned up on the pivot 6 to allow the
length of the pins K' to be adjusted without removing the key or digital from the
bench and for the purpose of verifying the evenness of the heads of the bolts with
the upper surface of the bar D.
The devices above described for adjustment will usually only need to be employed
when the transposition keyboard is first applied to an instrument and when the
exact relative positions of the digitals and the operating keys levers or parts
beneath have been ascertained. The apparatus may it will be readily seen by the
foregoing description be attached to an instrument so that it may be removed and
replaced at will without requiring further adjustment in any way.
Having now described and particularly ascertained the nature of the said
Invention and the manner in which the same is or may be used or carried into
effect I would observe in conclusion that what I consider to be novel and original
and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is :-
First: Providing pianos organs or like instruments with a transposition key
board consisting of the combination of a stationary frame set over the keys or
operating levers or parts of the instrument and carrying pins bolts or plungers
corresponding to the said keys or operating levers or parts and of a sliding frame
carrying keys or digitals acting when struck through the said pins bolts or
plungers in the stationary frame upon the keys of the key board proper or the levers
or parts by which the notes are sounded all substantially as and for the purposes
hereinbefore described.
Second In a transposition key board for pianos organs or like instruments a
bar carried in a frame separable from the key board proper or operating levers or
parts and set over it the upper parts of the said bar being in the same plane and
the said bar carrying transmitting pins bolts or plungers normally not in contact
with the keys or digitals of the sliding frame all substantially as and for the
purposes herein before described.
Third: In a transposition key board for pianos organs or like instruments the
combination with a rigid frame (set over the keys or operating levers or parts and
separablo therefrom, in which rigid frame is carried intermediate transmitting
mechanism) of a sliding bank of keys or digitals pivotted to a back piece or pieces
attached to the rear of the said rigid frame as and for the purposes hereinbefore
described.
Fourth-The herein before described improvements in pianos organs or like
instruments which can be operated upon through a key board the said improve-
ments consisting in providing them with an arrangement or combination of parts
substantially as hereinbefore described whereby the transposition from one key to
another may be mechanically effected.
In witness whereof I the said John Henry Johnson have to this my Specification
set my hand and seal this twenty-eighth day of April One thousand eight hundred
and eighty four