Improvements in Pianoforte Actions.
Year: 1887

page_text: Date of Application, 11th Jan., 1887
Complete Left, 11th Oct., 1887
Complete Accepted, 11th Nov., 1887
PROVISIONAL SPECIFICATION.
Improvements in Pianoforte Actions.
1 AUGUST KAMPE of Moscow (Gazetny pereoulok h. Korzinkin) Piano Manufacturer
do hereby declare the nature of this Invention to be as follows:-
This Invention relates to improved mechanism for Pianoforte Actions which is
equally applicable to Grand and Cottage Pianos of all descriptions and unites great
simplicity and strength of construction with remarkable precision of action.
An essential peculiarity of the improved mechanism is that the motion or impulse
of the key is transmitted to the jack or hopper by means of an oscillating angular or
bent lever carried by the key the jack bearing against the internal angle of the said
lever which at that place is provided with a corresponding notch step or bearing.
The lower end of the jack is thus supported and slides upon a smooth surface parallel
to the grain of the wood which always remains smooth and is not affected by
atmospheric influences and a more regular action is obtained than when the jack
slides in the usual manner across the end of the grain.
The said bent lever is adjustably attached to the end of the key by means of an
adjustable regulating plate.
In the internal angle of the lever is made a step or notch which acts on the lower
end of the jack the upper end of which is hinged to the hammer so that when the key
is depressed and consequently its internal end raised the jack causes the hammer to
strike against the strings. At the same moment the horizontal arm of the lever
comes in contact with a stop screw and being held back by the same the vertical arm
of the lever is caused to press against the jack so that the latter escapes from or slips
off the aforesaid step or notch and the hammer falls onto a support carried by the
key or by the frame. To prevent the jack from being thrown too far when the key is
violently struck the jack is held or checked on the opposite side by a counter support
or check which is contiguous to a projection on the jack and is attached to a spring
adjustably secured to a bar or support.
The pressure produced by the check on the jack can be regulated by a screw acting
on the spring or on a plate carrying the spring. In order to prevent every possibility
of the jack moving sideways its lower end can be provided with a steady pin passing
C

page_text: through a corresponding slot in the vertical arm of the bent lever or directed down-
wards and passing through a slit in the horizontal arm of the said lever. The vertical
arm of the bent lever is provided with a recess or cavity of peculiar curved shape on
the side facing the jack being so arranged as to cause the hammer to leave the strings
immediately after striking.
Springs fastened to the jack and to the hammer may be employed if desired in
order to regulate the lightness of the touch by counterbalancing the hammer or the
reverse.
The damper is fixed to the end of a lever which is hinged to a stationary bar
carrying the hammers. The damper is pressed against the strings by means of
springs. The lower end of the damper lever is jointed to an adjustable link which is
provided with a pad or cushion bearing against the inclined part of a projection on
the jack. The link is also provided with a guide pin passing through a corresponding
slit in the jack and serving to prevent the link from moving sideways. When the
jack is raised the inclined projection acts upon the link and causes the damper to
leave the strings. All the dampers can be taken off at once by turning a rod or
spindle in the usual manner.
Dated this 11th of Ta..
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London,
Agents for the said August Kampe.

page_text: Improvements in Piano-forte Actions.
I AUGUST KAMPE of Moscow (Gazetny pereoulok h. Korzinkin) Piano Manufacturer,
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:
This Invention relates to improved mechanism constituting piano-forte actions,
which is equally applicable to all kinds of pianos such as those known as grand and
as cottage pianos for example. The actions according to this Invention unite great
simplicity and strength of construction with remarkable precision of action of
the keys.
These advantages can be according to this Invention obtained without the aid of
springs with the exception of a support on a springy wire for supporting the rod
serving to raise the hammer.
In the annexed drawings Figure 1 shews an action constructed or arranged according
to this Invention applied to a grand piano. Figure 2 shews a modification of the
same mechanisin; Figure 2 a represents a modification in the mode of direction of the
raising rod, jack, or hopper. Figure 3 shews a further modification of the mechanism
applied to an upright piano with an improved mute-mechanism all as hereinafter
described.
An essential peculiarity of the action according to this Invention is that the motion
or impulse given to the key in playing is transmitted to the jack or hopper a by means
of the oscillating angular lever b, the jack a bearing against the internal angle of the
lever b, which at that place is provided with a corresponding notch step or bearing o.
The lower end of the jack a is thus supported and slides upon a smooth surface parallel
to the grain of the wood, which always remains smooth and is not affected by
atmospheric influences and a more regular action is obtained than when the jack
slides as hitherto across the end of the grain of the wood. The said bent lever bis
adjustably attached to the hinder or inner end of the key A by means of an
adjustable regulating plate B so that the said lever b can oscillate on the end of the
said plate B. In the internal angle of the lever is made the step or notch o and on
it bears the lower end of the jack a the upper end of which is hinged to the hammer C
so that when the key is struck and consequently its inner or rear end is raised the
jack a causes the haunner C to strike the string 1. At the same time the horizontal arm
of the lever b comes into contact with a stop-screw p and being thereby held back the
vertical arm of the lever b is caused to press against the jack a, so that the latter
escapes from or slips from off the step or notch o and the hammer C in consequence
leaves the strings and falls on to a support which is carried by the key A in Figure 1
(or, in the mechanism for upright pianos carried by the frame as at ' in Figure 3)
when the key is left free. To prevent the jack a from being thrown too far by the
vertical arm of the lever 6 when the key is violently struck, the jack a is held or
checked on the opposite side by a counter support d, which is contiguous to the
projection a' on the jack a and is attached by a wire spring c to the plate t, secured to
the rigid cross bar D (Figure 1), on which cross-bar D the hammers Care carried.
Or the wire c can also be fixed by means of the regulating plate e¹ and the bar s to

page_text: the bar E, which supports the hinder ends of the hammers as shewn in Figure 2, or
the said wire can be fixed to a special bar as shewn at D' in Figure 3.
The pressure produced by the check d on the jack a can be regulated by a screw e
(Figure 1) acting on the spring c or by a screw acting on the plate el carrying the
spring as in Figures 2 and 3. In order to prevent any possibility of the jack a
moving sideways, its lower end can be provided with a steadying pin f'passing
through a corresponding slot in the vertical arm of the lever as in Figures 2 and 3
or a similar pin can be directed downwards and pass through a slit in the horizontal
arm of the said lever b as shewn in Figures 2 and 3.
The vertical arm of the lever bis provided with a recess or cavity of the peculiar
curved shape shewn on the side facing the jack a being so formed as to cause the
hammer to leave the string immediately after striking it even when the keys are
pressed slowly.
The arrangement shewn in Figure 2 differs from that shewn in Figure 1 in that
the support d'and the stop screw p are placed in the rear of the jack a instead of in
front thereof, and that the angular lever bis situated reversely on the other side of
the jack a.
Figure 2 shews also how springs g g can be employed fastened to the
jack a and hammer C respectively, their office being to modify the "touch
according to the position of the spring g¹, it can be made to more or less counter-
balance the hammer C to give lightness of touch or it can be made to press the
hammer downwards for a "touch" of the reverse character.
22
as
In the mechanism for upright instruments a novelty is also the mute- or damper-
mechanism represented by Figure 3. The mute or damper k is fixed to the end of the
lever i which is hinged to the stationary bar u carrying the hainmiers C. The mute or
damper is pressed against the string by means of the spring v. The lower end of
the lever i is jointed to an adjustable link A, which is provided with a pad or cushion /¹
bearing against the inclined part of the projection a² on the jack a.
The link is also provided with a guide pin passing through a corresponding
slit in the jack a and serving to prevent the link from moving sideways. When the
jack a is raised the inclined projection a² will push the stop screw or link to the
right of Figure 3 causing the inute or damper k-to leave the string. All the mutes
or dampers can be taken off at once by turning a rod or spindle z in the usual way.
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 :-
1. The Mechanism for all kinds of Pianofortes whether grand or upright consisting
in the combination of the angular lever carried by the key A, with the jack or
hopper a, jointed to the hammer-C and with the support d and also with the stop p,
essentially as hereinbefore described and illustrated by the accompanying drawings.
2. The notch step or bearing o in the internal angle of the lever b, whereon rests
the raising rod a in such way that it slides on a smooth surface parallel to the fibres
of the wood and not on the cross-grain substantially as hereinbefore described.
3. The peculiar shape of the notch in the vertical arm of the lever whereby the
hammer Cleaves the string immediately after the stroke, even when the key is pressed
slowly substantially as hereinbefore described.
4. The mute mechanism consisting in the combination of the lever i with the link,
which is pushed aside by the projection a² of the jack a substantially as hereinnefore
described and illustrated in Figure 3 of the accompanying drawings.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C.,
Agents for the said August Kampe.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C.,
Agents for the said August Kampe.