Improvements in or Applicable to Pianofortes and like Instruments.
Year: 1887

page_text: Date of Application, 8th Mar., 1887
Complete Left, 5th Dec., 1887
Complete Accepted, 6th Jan., 1888
PROVISIONAL SPECIFICATION.
Improvements in or Applicable to Pianofortes and like
Instruments.
I ANDREAS LODEWYK KROM, of Utrecht, in the Kingdom of Holland, Manu-
facturer, do hereby declare the nature of this invention to be as follows:-
Hitherto the key-boards of pianofortos and like instruments having keys have
only been adapted for the use of adults, the use of such instruments by children
being difficult by reason of the keys of the key-board being too wide apart for the
small span of children's hands.
Now the object of my invention is to obviate this objection and the invention
consists in the employment of a double key-board one of which boards is provided
with keys of ordinary size whilst the other has a narrower set of keys. The said
keys are arranged on the two sides of a flat frame which can be withdrawn from and
pushed back into the instrument in such a manner that either of the key-boards can
be caused to operate the mechanism.
Or the frame can be arranged so that it can be turned in another frame, a complete
separation from the instrument not being then required.
Dated the 7th day of March 1927
G. F. REDFERN,
4, South Street, Finsbury, London,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in or Applicable to Pianofortes and like
Instruments.
I. ANDREAS LODEWYK KROM, of Utrecht, in the Kingdom of Holland, Manu-
facturer, 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 :-
Hitherto the key-boards of pianofortes and like instruments having keys have only
been adapted for the use of adults, the use of such instruments by children being
difficult by reason of the keys of the key-board being too wide apart for the small
span of children's hands.
Now the object of my invention is to obviate this objection and the invention
consists in the employment of a double key-board one of which boards is provided
with keys of ordinary size whilst the other has a narrower set of keys. The said
keys are arranged on the two sides of a flat frame which can be withdrawn from
and pushed back into the instrument in such a manner that either of the key-boards
can be caused to operate the mechanism.
Or the frame can be arranged so that it can be turned in another frame, a complete
separation from the instrument not being then required.
In order to enable my invention to be fully understood I will describe how it can
be carried into practice by reference to the accompanying drawing in which
Figure 1 is a side elevation of part of a pianoforte with my improvements applied
thereto. In this view the double key-board is shewn adapted to be revolved or
turned over in order to change the wider for the narrower set of keys or vice
versâ, the double key-board being represented partially so revolved or turned over.
Figure 2 is a vertical section of Figure 1, but shewing the double key-board in
position for playing the instrument.
Figure 3 is a horizontal section of the instrument shewing a plan of the key-
board with the narrower set of keys for children's uso in position for playing the
instrument.
Similar letters in all the Figures represent similar parts.
The two sets of keys a and b respectively are arranged one on each of the flat
sides of a frame A which turns on a pivot i mounted in a frame c.
The frame chas
runners e, e sliding in grooves in the sides d, d of the instrument and by this means
the frame c can be pulled out and pushed back like a drawer; the key levers of the
narrower set of keys diverge as shown in Figure 3 in order that they shall
correspond with the same hammer-mechanism as the ordinary keys a.
If for example the ordinary set of keys a for the use of adults be in position for
playing the instrument as shown in Figure 2 and it is required to bring the narrower
set of keys into playing position for children's use it is only necessary to pull out the
frame c with the frame A until the ends of the key levers are no longer under the
hammer-mechanism when the frame A can be turned over, in the manner indicated

page_text: in figure 1, on its pivot i and the lower key-board be thereby brought uppermost
into a horizontal position. The frame c with the keyboards must then be pushed
back into the case of the piano, the ends of the key-levers will come under the
hammer-mechanism and the key-board with narrow set of keys suitable to be
manipulated by the small hands of children is in position ready for playing as shewn
in figure 3.
The hereinbefore described construction can be simplified by making the frame A
to slide directly in the sides d of the case of the instrument, the frame e being then
dispensed with. In this case in order to change the koy-board the frame A must be
entirely drawn out from the sides d; it must then be reversed and pushed back
again.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed 1 declare that what
I claim is
1. A piano or other like keyed instrument having a double koy-board, the said
key-boards being arranged one on each side of a frame which is either pivotted in a
sliding frame or adapted to slide directly in the case of the instrument.
2. The improved pianoforte hereinbefore described with reference to the accompanying
drawing.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.