IMPROVE- MENTS IN REGULATING DIGITORUMS,' PIANOFORTES, HARMONIUMS, ORGANS AND OTHER KEY BOARD INSTRUMENTS
Year: 1884

page_text: I, THOMAS STORY HORN of Elgin Road, Croydon in the County of Surrey
Manufacturer do hereby declare the nature of my said invention for "IMPROVE-
MENTS IN REGULATING DIGITORUMS,' PIANOFORTES, HARMONIUMS, ORGANS AND
OTHER KEY BOARD INSTRUMENTS" to be as follows:-
This Invention is an Improvement upon the one for which Letters Patent were
granted to me and another the 21st Febry 1880 and numbered 768 and which had
for its object the providing of means whereby the resistance of the keys and their
depth of touch could be adjusted at will.
Now by this Invention I make the keys much longer than according to the above
Invention of 21 Febry 1880 N° 768 and instead of their working from a fulcrum
at end, I form an arched notch at a desired distance from the end which crosses the
keys upon the underneath side. The keys are placed in position upon a bed
supporting a half round or other suitably shaped rod corresponding in diameter to
the arched notch in keys, so that the notches in keys rest upon the rod aforesaid.
This forms the fulcrum from which the keys according to this Invention, are
worked. Centre pins are placed upon this rod, one for each note. The upper side
of key, at back part, I build up to be horizontal and in same is a groove running
lengthwise, in which works a spring for regulating the pressure desired. The
spring is attached to a frame above these keys, which frame is supported upon two
slides running backwards and forwards at will, one at each side of Instrument.
These slides are kept in position by guides. This frame holding the spring may be
of any length and sustain any number of springs (one to each note) required and is
worked by a screw placed at back of Instrument. When it is desired to add weight
the springs are drawn back, by means of the screw, and when less pressure is
required the springs are drawn forward towards the fulcrum upon which the keys
work. Underneath the front ends of keys I form a frame, working from fulcrum
at back which by being raised or lowered diminishes or increases, as the case may
be, the depth of touch required. A bar goes across the keys on upper side in front
of fulcrum point through which is a screw in connection with the frame aforesaid.

page_text: By turning this screw the under frame is raised or lowered as required and the
keyboard with it.
Should it be desired to remove a note or key for any purpose, easy access to the
same is obtained by removing the screws keeping the frame which bears the springs,
in position, said frame being in connection with two guides or bars hinged at back. 5
These guides or bars may be lifted up when springs and frame will all be raised.
together and allow of any of the keys being easily removed.

page_text: .
I, THOMAS STORY HORN, of Elgin Road, Croydon, in the County of Surrey,
Manufacturer, do hereby declare the nature of my said Invention for "IMPROVE-
MENTS IN REGULATING DIGITORUMS, PIANOFORTES, HARMONIUMS, ORGANS, AND
OTHER KEYBOARD INSTRUMENTS," and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement,
reference being had to the accompanying drawings, and to the letters of reference
marked thereon, that is to say :—
This Invention is an improvement upon the one for which Her Majesty's Royal
Letters Patent were granted to me and another, the 21st February 1880 Numbered
768, and which had for its object the providing of means for strengthening and
developing the muscles of the fingers of pianoforte players and others, by adjusting
at will the resistance of the keys, and their depth of touch.
Now by this my present invention I construct a regulating "digitorum," or other
keyboard instrument which is even more effective than that for which Letters
Patent have been previously granted to me, as aforesaid, and which is also simpler
in its detail, and at the same time constructed and fitted at much less cost, with
less likelihood of any part getting out of order or repair.
And, in order that this my Invention may be fully understood, reference is liad to
the accompanying drawings. Figure 1, is a longitudinal section of a regulating
digitorum constructed in accordance with this my invention. Fig 2, is a view of
inner side of casing of instrument; Fig 3, is a plan of the side of casing, Fig 4 &
plan of my regulating digitorum with keys removed, Fig 5 shews the underneath
of spring rail, and Fig 6 an end view of same. Similar letters of reference refer to
like parts in all the figures.
In this my invention I make the keys A longer than according to my aforesaid
invention of 21" Feby 1880 N° 768, and instead of their working from a fulcrum
at the end of key, I form an arched notch a at a desired distance from the end
which crosses the keys A upon their underneath sides. The keys A are placed in
position upon a centre rail B supporting a half round, or other suitably shaped rod b
corresponding in diameter to the arched notch a in keys A so that the notches in
keys rest upon the rod b aforesaid. This forms the fulcrum from which, according
to this my invention, the keys A are worked. Centre pins C are placed upon this
rod b, one for each note.
The upper side of key A, at back part, I build up to the horizontal, and in same
I make a groove D shewn in dotted lines Fig 1 running lengthwise, in which groove
works a spring E for regulating the pressure desired.
The said spring E is attached to a frame F (which I call the spring rail) above
the keys. A, and the frame F is supported upon two slides G running backwards and
forwards, at will, one at each side of instrument. These slides G are kept in
position by guides H.
The frame F holding the spring E may be of any length, and may be of wood or
ron, or of wood and iron, and may sustain any number of springs E (one to each
note) required. It is caused to travel by a screw H placed at back of instrument.
When it is desired to add weight, the springs E are drawn back by means of the
crew H, and when less pressure is required the springs E are driven forward towards
he fulcrum upon which the keys work.
Attached to the slide of spring rail F is a pointer P shewing on an index the
ariations of pressure.
Beneath the front ends of keys A I form a frame K, which I call the depthing
ail, working from a fulcrum L at back which depthing rail K. by being raised or

page_text: lowered diminishes or increases (as the case may be) the depth to which the keys
fall. A bar M (the key rail) crosses the keys A on upper side in front of fulcrum
point, through this key rail there is a screw N in connection with the frame K
aforesaid. By turning the nut thumbscrew O at upper end of screw N the frame K
is raised or lowered as required, thus regulating the depth of touch of the keys.
An index finger may also be fitted to the frame K for the purpose of indicating the
depth of touch to which the keys are regulated.
R is the back rail and S the front rail, with pin 8 for taking into front end
of key A.
When it is required to remove a note or key for any purpose, easy access to the
same is obtained in this my invention by removing the screws keeping the spring
rail F, and the bar M in position, and the slides Ġ may easily be withdrawn by
taking out the back end of casing.
Having now particularly described and ascertained the nature of this my
invention and in what manner the same is to be performed I declare that what
I claim is
First. The construction and arrangement, at the sides of regulating digitorums,
pianos, harmoniums, organs and other keyboard instruments of the slide G (bearing
spring rail F) and guides H substantially as and for the purposes hereinbefore set
forth and described.
Second. The method or arrangement whereby the springs are caused to travel
upon the upper side of keys for the purpose of giving more or less resistance to tho
keys substantially as herein before set forth.
-
Third. The arrangement and construction of depthing rail K. substantially as and
for the purposes herein before set forth and described.
Fourth. The special construction of keys A substantially as hereinbefore set forth
and described.
Fifth The general arrangement and construction of regulating Digitorums, pianos,
harmoniums, organs and other keyboard instruments substantially as and for the
purposes herein before set forth and described.
Duted this Sixth day of November 1884.