IMPROVEMENTS IN PIANO- FORTES
Year: 1882

page_text: LETTERS PATENT to William Thomas of the firm of Hemingway and Thomas
of Kentish Town in the County of Middlesex, Piano-forte Manufacturers.
PROVISIONAL SPECIFICATION left by the said William Thomas at the
Office of the Commissioners of Patents on the 18th December 1882.
WILLIAM THOMAS, of the firm of Hemingway and Thomas, of Kentish Town, in
the County of Middlesex, Piano-forte Manufacturers, "IMPROVEMENTS IN PIANO-
FORTES
"
My invention relates to piano-fortes, and is designed to provide certain improve-
ments in the action of these instruments, which improvements have for their chief
objects to simplify the arrangements for moving various parts, whereby, there being
less resistance to the touch of the player, he is enabled to play with greater. facility
than is possible with instruments as ordinarily made; also to so construct and
arrange certain parts of the action that whenever they require to be repaired,
altered, or adjusted they can be readily manipulated for these purposes without
the necessity for removing other parts in the manner heretofore indispensable.
In carrying my said invention into practice I provide a jack-guide made of metal
pins or pieces which are secured within a hammer-rail whose face is bevelled or
inclined in such a manner that the narrowest part in transverse section is at the
bottom, the thickness increasing gradually in an upward direction.
The jack
works between these metal pins; I arrange the set off screw or pin in the jack and
it passes through the latter at an angle corresponding with that of the hammer-
rail. The stroke or travel of the hammer can be regulated to a great nicety by
turning this screw or pin, which, by reason of its position, is readily accessible to
the hand.
I connect the damper-wire to the top of the jack in such a manner that it may
at any time be readily removed without disturbing any adjacent, or other, parts of

page_text: the action, that is to say, the lower end of this wire is bent at a right angle and
the bent portion is inserted within an opening in the jack, which opening is closed
by a flap or piece of the wood forming part of the jack and hinged in such a
manner that it can be turned down to release the wire, by removing a screw which
unites the flap to the body of the jack. The damper-wire extends upwards from
the top of the jack almost perpendicularly, thereby providing for a direct lifting
action which diminishes the weight to a degree which considerably facilitates the
playing of the instrument.
The piano-forte action made according to my said invention requires only four
centres or pivots for the parts to work upon, which, it will be obvious, is a
considerable advantage.

page_text: :
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Thomas in the Great Seal Patent Office on the 18th June
1883.
WILLIAM THOMAS of the Firm of Hemingway and Thomas of Kentish Town in
the County of Middlesex, Piano-forte Manufacturers "IMPROVEMENTS IN PIANO-
FORTES
This Invention relates to improvements in the action of piano-fortes and has for
its object a simple and effective construction which not only affords great facilities
for repairing regulating and adjusting the mechanisin of the action' but also
facilitates the manipulation of the keys of the instrument by diminishing the
resistance to the touch thus enhancing both the delicacy of tone and the durability
of the instrument
In order that my said invention may be better understood and readily carried
into effect I will now with the aid of the accompanying drawings whereon similar
letters of reference indicate corresponding parts proceed to more particularly describe
the same
Figure 1 shews a view in side elevation of a portion of the action of a piano-forte
having my improvements applied thereto
The remaining figures shew detail views of portions of my improvements and are
hereafter more particularly referred to
}
I
:
My first improvement relates to an improved construction and arrangement of
the jack and hammer rail for the purpose of controlling and regulating the action.
of the hammer which is as follows I provide a jack guide consisting of two metal
pins (a) only one, of which is seen in the drawings Figure 1-inserted in the
hammer rail (b) between which the jack (c) works up and down The face (d) of
such hammer rail is bevilled or inclined the narrowest part. being at the bottom
while it gradually increases in breadth upwards
.A. set off screw pin (e) passes through the jack obliquely at such an angle as to
ensure the butt end of the pin (f) working fairly against the bevelled face of the
hammer rail and by turning such screw pin either to the right or left the stroke or
travel of the hammer (g) can be controlled and regulated to the utmost nicety
thus not only ensuring the hammer delivering the requisite blow for. the production
of the proper quality of tone but also preventing all possibility of its blocking
which is a great advantage
The head (h) of such screw pin projects in front of the jack in such a position as
to be within easy reach of the hand
My second improvement relates to an improved method of connecting the damper
wire with the jack so that not only can such wire be readily removed and replaced
when necessary without disturbing any other parts of the action (a most important
advantage when tuning and regulating the instrument) but much greater delicacy
of touch is obtained-The following is an accurate description of this part of my
invention
Fastened to the top of the jack (c) by a screw (¹) is a face plate (i) (in my
Provisional Specification termed a flap) having a small horizontal groove (j) on its
inner surface as shewn at Figure 2 while a corresponding groove (¹) is cut on the
top of the jack as shewn at Figure 3-Such face plate is so fitted to the top of the
jack that the two grooves come opposite each other and thus form a channel to
receive the lower end (k¹) of the damper wire (k) This lower end is bent to a
suitable angle as shewn in Figure 4 and is then inserted in such channel wherein
it is securely held by tightening up the screw (i)-In order to prevent the wire
chattering I line the contact surfaces of the jack and face plate with felt

page_text: When it is desired to release the end of the damper wire it is only necessary to
loosen the screw e when the wire can be at once drawn out and readjusted
This improved construction affords great facility for remedying any defect in the
mechanism of the action without the aid of skilled labor and particularly is of
great advantage and convenience when the instrument is being tuned
In order to obtain the increased delicacy of touch before referred to I so fit the
damper wire that it extends upwards from the top of the jack almost perpendicularly
so that when actuated it exercises a direct lifting power upon the damper and thus
greatly diminishes the force requisite for the manipulation of the keys of the
instrument by the player thus producing an exquisitely sensitive touch
•
Another great advantage of my improved construction and arrangement of the
action of a piano-forte is that only four centres or pivots marked respectively 1-2-
3-4 are required for the parts to work upon instead of six, seven, eight or more as
hitherto owing to the simplicity of my improved construction which renders
superfluous many of the mechanical parts now in use thus rendering the action far
more durable both by reducing the wear and tear and diminishing its liability to
get out of order whether from the effects of damp or otherwise
Having thus particularly described and ascertained the nature of my said
invention of improvements in piano-fortes and the manner of carrying the same
into effect I claim as novel and of my invention
1° The improved combined construction and arrangement for controlling and
regulating the action of the hammer consisting of guide pins (a) bevil faced hammer
rail (b) jack (c) and screw pin (e) arranged and fitted substantially in the manner
and for the purposes herein before described and illustrated
2° The improved combined construction and arrangement for connecting and
disconnecting the damper wire and jack consisting of jack (c) face plate and
screw (i. ¹) grooves (j.j.) and damper wire (k) with bent lower end all arranged
and fitted substantially in the manner and for the purposes hereinbefore described
and illustrated
3º The employing four centres or pivots only as herein before described and
shewn
In Witness whereof I the said William Thomas have hereunto set my hand
and seal this 16th day of June in the Year of Our Lord. One thousand eight
hundred and eighty three
14
Witness
ELT & Co
Agents 33. Southampton Buildings
Holborn, London
“WILLIAM THOMAS (L.S:)