Year: 1887

page_text: ite of Application, 3rd Dec., 1387
Specification Accepted, 6th Jan., 1888
I, EMIL HUGO HÖFINGHOFF of Barmen, Rhenish Prussia Germany, Merchant 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:
My invention consists of a new arrangement of the keys of key instruments such
as pianos, harmoniums, cottage organs, church organs and similar key instruments.
The chief advantage which my new key board offers to the player is, that an
average hand can strike on it one octave more than on the key board hitherto in use.
To give an instance I may say that a hand, which can strike on the ordinary key
board the "contra C and the "great D" at the same time, is able to strike on my
new key board the "contra (" and the "small D" simultaneously.
From this it appears that on my new key board compositions can be played which
it would be impossible to execute on the ordinary key board. There are besides a
great many combinations of tones in existing compositions, which offer great diffi-
culties to the performer playing on the ordinary key board and which are easily
played if the player performs them on an instrument with my key board.
Hitherto it was impossible to perform compositions composed for the organ with
organ pedal on instruments having no organ pedal. Most of these compositions can
be performed on my new key board.
I attain this object by arranging the keys of my new key board as illustrated in
the accompanying drawing, in which:
Figure 1. is a vertical sectional view of the new key board for a pianoforte.
Figure 2. is a vertical sectional view of the same for a harmonium.
Figure 3 a. is a plan of my new key board having the prolongations of the lower
keys bent in an obtuse angle to the right.
Figure 3b. is a plan of my new key board having the prolongations of both sets of
keys bent in an obtuse angle, one set to the right and the other set to the left so that the
prolongations of the corresponding keys run in converging lines and meet at the point
where they act upon the inner mechanism of the instruments, be it for strings, hammers,
pipes, tongues, valves etc. of pianos, harmoniums or cottage organs respectively.
My new arrangement of keys consists of two sets of keys U U & L L in diatonic
CD 57

page_text: order placed one immediately behind the other, the back or upper one U U being
placed only so much higher than the front or lower one L L that both of them form
together but one uninterrupted key board and that the keys of both can be struck
conveniently by one hand at the same time, for the purpose of which the keys of the
upper set and the semi tones of the lower set are made shorter than usual.
In this my new key board differs materially from the two manuals of an organ on
which it would be impossible for instance to strike the white keys of the lower manual
and the semitones (black keys) of the upper manual simultaneously and conveniently
by the same hand and on which it would be impossible to play compositions like
those composed especially for my key board.
This new key board has two keys for each tone of the instrument, i.e. one key in
the front set and one key in the back set and thus each tone may be played on the
front set of keys or on the back set of keys. The keys are arranged in such a manner
that the keys of the back (upper) set give a tone sounding just one octave higher-
(or deeper) than the tone brought to sound by touching that key of the lower set
lying in a straight line before it.
This is obtained by bending the inner prolongations of the keys either of the lower
or of the upper set, M. or N respectively, oscillating on the pins O & P respectively
in such a way either to the right or left side, that the prolongations of the keys of
the lower set do not run parallel with the prolongations of the keys of the upper set,
but that the prolongation of each key of the upper set brings in action the same
hammer (pianoforte) or the same mechanism for opening the valves (harmonium)
which is connected with that key of the lower set, that lies an octave higher up or
lower down.
My invention does in no way relate to the inner mechanism of key instruments,
whether they be wind instruments acting by pipes and tongues and valves or string
instruments acting by strings and hammers and I make no claim or any arrangement
of this inner mechanism which as a matter of course in every case is prescribed by
the nature and construction of the instrument.
My invention consists solely in the new arrangement of the double set of keys
forming but one uninterrupted key board, by means of which it is possible to strike
with one hand over two octaves and to play an unlimited number of accords and
combinations of tones between this reach which it was hitherto impossible to perform
on the instruments with the ordinary arrangement of keys.
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 :
A key board composed of two sets of keys of the usual diatonic system, UU & LL
of which the upper set U U is placed immediately behind the lower set L L and only
so much higher that both sets form but one uninterrupted key board having for each
tone two keys, viz. one in the lower and one in the upper set, arranged in such a
manner, that:
A. each key of the lower set gives a tone sounding either one octave deeper or one
octave higher than the tone produced by striking that key of the upper set which lies
in the direct prolongation of it and that
B. the white keys of the lower set and the semitones (black keys) of the upper set
can be struck conveniently by one hand simultaneously."
nahin 20th dom af Naha 1987
KARL T. MAYER,
Agent for Applicant.