Manufacturer.
Year: 1895

page_text: Date of Application, 16th Mar., 1895-Accepted, 20th Apr., 1895
A communication by HEINRICH KAIM, of Kirchheim-under-Teck, Wurtemberg,
in the Empire of Germany, Piano Manufacturer.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool, and 6, Bank Street,
Manchester, both in the County of Lancaster, 118 New Street, Birmingham in
the County of Warwick and 31 High Holborn in the County of Middlesex,
Civil Engineer, 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 has for its object to make the repetition action in pianos effective
by means of a special arrangement whereby on a short cessation of pressure on the
keys the hammer is prevented for a short time from falling back, whilst the hopper
returns immediately under the hammer butt in such a way that by a light touch on
the keys the hammer is immediately again caused to strike. Further, the drawing
back of the hammer is effected from the hopper itself by means of a bent metal
pin attached to the hammer butt instead of by the action hitherto employed.
Further the check is here not arranged on the usual lever but on a special lever
which is necessary for the new repetition action, whereby an improved damper
lifting mechanism for the separate keys and for the forte may be employed.
In the accompanying drawings, this improved mechanism is shown on one sheet
for pianos with overhead check on the hammers, that is without a counter check on
the hammer, and on the other sheet for pianos with a counter check on the hammer.
The hammer check itself is in both forms of construction operated by the improved
mechanism hereinbefore mentioned.
In Sheet 1 of the drawings,
Figures 1, 2 and 3 show a sectional side elevation, front elevation and partial
plan respectively of the improved mechanism with an overhead check on the
hammer and with special repetition action.
Sheet 2 shows in Figures 4-6 similar views of the mechanism with counter
check on the hammer.
The lever B is operated in the usual manner by means of the sticker L from the
rear of the key T. The hopper G is arranged on the lever B in the usual manner.
The check F and damper H are operated by means of a new lever A which is
pivotally connected to the rail D and is moved by an arm on the sticker L by
means of an adjustable link M. On the front part of the lever A the check arm I
with the check is secured, the padded or leather coated under surface of this
check bearing when checking the hammer on the upper padded surface of the
hammer head e.
An elbow lever C is further pivotally attached to the rail D. The longer arm o
of this elbow piece C, which renders the repetition possible, rests with its point
against the front of the padded hammer head after the stroke of the hammer has
taken place and slides gradually upwards on the padding so that the hammer for a
short time is checked in its return movement, and opportunity is afforded for the
hopper G to immediately return under the hammer butt e'. The precise adjustment
of the elbow piece C is effected by means of an adjustable contact piece or button
arranged on the check arm F. This button has also the function of returning the

page_text: elbow piece C into its normal position by pressing on its short arm c². The action
hitherto employed at the butt of the hammer is replaced by a bent metal pin e
attached to the under part of the hammer butt e', which pin passes through a slot
in the hopper G. The form of the pin is such that the end of the hopper may
unimpededly slip out of the way on the stroke of the hammer. This arrangement
is much simpler and more durable than that hitherto employed.
By the arrangement of the check F on the new lever A, instead of on the
lever B, the disadvantage of the check pressing the hammer against the strings is
avoided in the case of over pressure being applied to the keys.
Hitherto many
otherwise well built instruments have been made unuseable owing to this defect.
In order to effect the new separate raising of the dampers there is provided on
the rear side of the new lever A, an adjustable contact piece or button a. This
presses on the spoon-shaped end of the horizontal arm of the damper lever H
which latter is pivotally attached to the damper rail K.
The lifting of the various dampers for the forte is effected by means of a round
iron rod extending across all the levers which is pivotally arranged with its axis
of rotation coinciding with the axis of rotation o of the damper levers whereby a
rubbing friction of the rod J on the damper levers is avoided.
Instead of lifting the dampers for the forte by means of the rod J, there may
be employed, as shown in Sheet 2, a covered bar J and an elbow piece or hook h
fastened on each damper lever in such a way that the bar J' lies between the bent-up
ends of the hooks 2 and the levers H. The dampers may then either be arrested
by means of the bar J1 (which passes through them all) or they may be raised for
forte playing.
This new method of raising the dampers affords the essential advantage that the
raising by the separate keys may be conveniently effected from the front by means
of the contact a. It is also possible by means of the rod J or the bar J to
regulate the forte raising in the simplest manner from the front.
The hammer rail consisted formerly of one piece. In the improved arrangement
shown on Sheet 1 two rails are employed. The damper rail K is attached to the
iron frame in front of the strings, whilst the hammer rail K' together with
the mechanism fastened thereon may be taken out, so that when working on the
mechanism or the dampers, the parts will not be in the way of one another.
The damper rail K is screwed together with the hammer rail K' in the spaces
between the supports and thus the former carriers are unnecessary.
By the arrangement of moving the checks and dampers from a special lever
instead of from the usual lever which special lever is operated by means of an arm
on the sticker, the weight of the inserted parts more nearly equipoises the keys, and
consequently the operation of the mechanism is essentially facilitated.
The cost of the improved mechanism is not at all or only slightly greater than
that of the mechanisni previously employed.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1. A repetition action for pianos consisting in operating the hammer check F by
a special inserted lever A or A' instead of by the lever B hitherto employed for
this purpose, said special lever being operated by an arm attached to the sticker
and directed towards the key centre in such a manner that even in the case of
over-pressure, the check does not press the hammer on the strings, and the operation
of the mechanism is easier and requires less force substantially as described and
illustrated.
2. In the repetition action as described in Claim 1, the further arrangement of
operating the dampers from the special lever A or A' instead of from the lever B
hitherto employed by means of an adjustuble contact piece or button a or a
arranged thereon, the lifting or raising of the dampers by means of these contact
pieces being conveniently regulated from the front, whilst for lifting for forte,

page_text: there is employed either a round iron rod J lying behind the damper levers, the
axis of rotation of which bar coincides with the axes of the damper levers or a
bar J which lies in front of the damper levers and within elbow pieces or hooks *
attached to the latter, by means of which bar the dampers may either be stopped
or raised for forte playing substantially as described and illustrated.
3. In the repetition action described in Claim 1, the arrangement of two rails
instead of one as formerly for the dampers and hammers respectively, the damper
rail K being fastened to the iron frame in front of the strings, whilst the hammer
rail K is screwed on the damper rail in the spaces between the supports, by which
means the carriers previously employed are dispensed with, whereby after the
hammer rail K' with its attached mechanism has been taken out, work can be done
to the latter or to the dampers more conveniently substantially as described and
illustrated.
4. For use with the repetition action described in Claim 1, an elbow piece or
repetition lever Coperated by a contact piece or button arranged on the check
arm F in such a manner that after a blow of the hammer, the point c of one arm
of this repetition lever bears against the padded rear part of the hammer head
and slips along this part of the hammer when the pressure on the keys ceases, so
as only to release the hammer after having passed over the padded part for the
purpose of checking the return of the hammer for a short time to allow of the
hopper returning under the hammer butt, substantially as described and illustrated.
5. For use with the repeating mechanism described in Claim 1, a device for
drawing back the hammer consisting of a curved metal pin 2 attached to the lower
part of the hammer butt e¹ in place of the mechanism hitherto employed for this
purpose, which pin 2 passes through a slot in the hopper G and is of such a shape
as to arrest the hopper after a stroke of the hammer but to allow the latter to pass
immediately and unimpededly again under the hammer butt e' when the pressure on
the keys ceases, substantially as described and illustrated.
Dated this 15th day of March 1895.
WM. P. THOMPSON & Co.,
Agents.