Improvements in Apparatus for Actuating Mechanical Keyed Musical Instruments.
Year: 1898

page_text: Date of Application, 2nd Mar., 1898-Accepted, 27th Aug., 1898
COMPLETE SPECIFICATION.
Improvements in Apparatus for Actuating Mechanical Keyed
Musical Instruments.
Instrument Maker,
We, WILHELM PAPE, 59, Gneisenaustrasse,
WOLF
HEILBRUNN, and SIMON BLUTH, both of 39, Keibelstrasse, Manufacturers, all of
Berlin, Germany, 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:-
―
Our invention relates to a pneumatic relay for the automatic playing of keyed
musical instruments of all kinds.
By means of this improvement the ease and quickness of the response are con-
siderably improved in that on the one hand the transmission of the motion from
the membrane of the primary relay to the valve of the secondary relay is effected
by means of a striker suspended as a pendulum, and on the other hand the valve
of the secondary relay itself is formed as a double valve with a closure on both
sides, so that it can be placed in the air channel leading to the key bellows instead
of being placed in a special chamber.
In the accompanying drawing, the improved relay is illustrated in vertical
section.
The primary relay is actuated by means of the note-sheet N, as the holes in the
latter upon passing over the channel L permit the entrance of the air into the
channel, so that the membrane C is distended. After the openings of the note-
sheet N have passed the channel L, the air is again withdrawn from the chamber A
through the somewhat smaller channel M.
The relay consists of the air chamber A common to all the keys and of the
usual form, from which the air is continuously drawn, passing through the
channel B which leads to a vacuum bellows. In the said air chamber A there
is placed, in addition to the membrane C for the primary relay L, a striker I)
supported on the rod E mounted as a pendulum, which striker is directly influenced
by the membrane C, and strikes upon a conduit F leading to the bellows G by
means of the leather shod valve I weighted with a piece of metal H. The weight H
is also provided with a leather flap 0, and forms together with the valve I a
double valve, which according to its position brings the channel F either in com-
munication with the outer air through the hole K, or with the air chamber A
through the hole S.
The operation of this relay is exactly the same as with the relays hitherto in
use, with the sole difference that the channel F leading to the bellows G is con-
structed correspondingly short and narrow in order to effect a very quick evacua-
tion of the bellows G, and a relatively large membrane C influences the valve I
of the secondary relay by means of the aforesaid pendulous and therefore easily
movable striker D, so that in consequence thereof the response of the organs
moved by means of the bellows G, such as the key T or the striking mechanism of
a piano is quickened.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is:
1. Pneumatic relay for automatic pianos and the like characterized by the
arrangement that the transmission between the primary and the secondary relay
is effected by a striker suspended like a pendulum.
2. A modification of the relay characterized in Claim 1 consisting essentially
in the use of only one vacuum chamber A with channels F leading to the bellows G
arranged so small that only a single double acting closing valve IO is required
for the secondary relay, which in turn is influenced for the purpose of obtaining
an extremely quick and precise response by the membrane C of the primary relay
through the action of the striker Ĺ suspended like a pendulum, substantially as
described.
W. P. THOMPSON & Co.,
322, High Holborn, London, W.C., Patent Agents for the Applicants.