Improvements in Pneumatic Wind-chests and Mechanism for Organs, Harmoniums, and the like.
Year: 1890

page_text: Date of Application, 22nd July, 1890-Accepted, 11th Oct., 1890
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IAmraז נום
Improvements in Pneumatic Wind-chests and Mechanism for Organs,
Harmoniums, and the like.
I, EMANUEL STEFAN PETR, of Prag-Zizkov, in the Empire of Austria, Master
Organ Builder, 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:-
The invention hereafter described relates to improvements in pneumatic wind
chests and mechanism for organs harmoniums and the like and its characteristic
feature is to reduce as much as possible the loss of compressed air in such mechanism.
The improvements are further characterized by the fact that manuals as well as pedals
and registers can be replaced by pneumatic mechanism.
The invention is illustrated on the accompanying drawings in which
Figure 1 is a longitudinal section through the wind chest.
Figure 2 shews several cross sections through the same and
Figures 3 and 3ª illustrate the connection between the keys of the manual, the
pedal or the register mechanism with the air conduit or chamber.
As shewn by these figures a wire a, leads from each key of the manual, pedal or
register A, to a movable bracket or tumbler c, to which it is fixed in such a manner
by a cap that the tumbler forms a double lever with arms of unequal length. The
tumbler is placed above the air chamber, connected with the wind chest the chamber
like the latter being filled with compressed air. The tumbler operates two valves d,
and e, the former serving as an outlet valve while the latter is used as a closing valve,
the two valves being correspondingly loaded. The valve d, whose wire a' connected
with the tumbler c, passes vertically through a small tube d', closes the air outlet
channel d², when the keys are in their normal position in the manual, and the valve e,
which opens inwards within the air chamber f, and is arranged below the mouth
of the air channel is actuated by the tumbler c, through the brass wire a², which
passes into the box G, through the tube c². When the keys of the manual are at rest
the valve e, is open and establishes communication between the air channel g, and the
air chamber f
The valves d, and e, have their lower sides covered with leather to render them
air tight and a wooden nut e', adjustable on the wire a² to regulate the opening of
the valve e, is similarly furnished. The arrangement of the tumbler c, is such that
when the keys A, of the manual are depressed and the wires a, thereby raised the
valve e, is closed and shuts off communication of the air chamber f, with the
channel, before the valve d, is opened to allow the air to pass from the air
conduit, and channel g, through the outlet d³, but when the key is not depressed
the outlet valve d is closed and the valve e, opened and the small wooden nut el,
resting upon the box G, prevents the escape of air from the air chamber f. The air
conduit, communicates with the bellows i, (Figure 1) one end of which is loaded
with a weight r, which promotes the rapid action of the bellows.
The bellows i, operate at their upper part against two valves k, l, mounted upon
a spindle the valve k, being an outlet and the valve I, a closing valve. The bellows i,
are arranged below the wind chest W, and when the keys are not depressed and
hence when compressed air is contained in the air conduit h, the valve k, is forced
by the air pressure and by the weight r, against the bottom of the wind chest W, so
that the chest is closed outwardly and the compressed air passes from the chest
through the valve l, and channel m, into the bellows n¹, n³, n³, these bellows which
D
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page_text: are likewise loaded by weights r, being thereby inflated. The bellows n³, n², n², carry
upon their upper sides closing valves o¹, 03, 0³, which are applied against the
outlets p, p, p³, in the pipe frame z, and close the said outlets when the bellows
are inflated. The hollow beam v, upon which the bellows n³, n², n³, are mounted is
built in the wind chest and is held at one end upon the rear wall of the said chests
by screws y. The valves o, are also influenced by the register in such a manner
that only these valves will be opened the corresponding register of which are drawn.
This is effected in the following manner: three registers are provided in the pneu-
matic wind chest of the organ as shown in the drawings, and their channels t¹, t²,
lead to the bellows q', 92, 93, the lower parts of which carry plugs s, by means of
wires u, these plugs resting against the upper parts of the bellows n', n², n³. The
bellows q, are arranged in the wind chest W, and have their lower surfaces fully
exposed to the pressure of the compressed air therein so that when there is no
compressed air in the bellows q, they are collapsed and the bellows n, boing thereby
maintained in inflation the valves o, are kept closed. When on the contrary
compressed air enters the channels t, the bellows q, are inflated and the consequent
downward movement of the lower parts causes the plug s, to sink and allows the
valves 0, to be opened.
The registers are so arranged as to contain usually no compressed air in their
channels & such air only entering these channels when the registers are drawn. As
shewn two registers t¹, ², are drawn, while the register t³ is pushed back, in con-
sequence whereof the bellows n¹² can only open the valves o¹ of when the air escapes
out of the air passage m owing to the valve being shut and the valve & being
opened.
In this pneumatic mechanism, when a manual pedal or register key is depressed
the playing valve comes first into action and causes the air conduit to communicato
with the atmosphere; then the bellows i operate and collapse, whereby the valve lis
allowed to close, while at the same time the outlet valve k opens and allows the air
to escape from the air channel m. As a consequence and under the simultaneous
influence of the bellows q the bellows n are collapsed and the valve o opened.
The above described pneumatic mechanism for organs has the well known advantage
that a great number of levers can be dispensed with, while as compared with other
similar mechanism, little compressed air is used when playing the organ such play
Furthermore
being greatly facilitated, improved in tone and rendered more accurate.
with the improved arrangement of the pneumatic wind chest all the play valves o,
all the bellows n and the hollow beam v can be withdrawn without having to interfere
with the pipe frame or with any other part of the mechanism.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what ]
claim is :-
:-
1. A pneumatic wind chest and mechanism for organs and harmoniums in which
the bellows connected with the air passages m carry directly the play valves in the
9 influenced by
wind chest and can only open the latter valves when the bellows
the pneumatic register or stops allow the bellows n, connected with the playin
valves o to collapse.
2. In the mechanism for organs claimed above, the arrangement of the tumbler
actuated by the manual, pedal or register keys A, and the unequal lever arms c
which operate, when the manual keys are depressed, the valves d and e in such
manner, that the valve e arrests first the escape of air from the air chamber
then establishes a connection between the air conduit h in front of the chest V
and the atmosphere, through the valve d.
an
3. In the pneumatic wind chest and mechanism for organs claimed above th
connection of the wind chest W with the air conduit by means of the bellows
which operates a double valve l, k, in such a manner that when the compressed a
L

page_text: escapes from the air conduit h, the air passages m are simultaneously shut off from
the wind chest and open to the atmosphere, substantially as described and shown in
the drawings.
Dated this Twenty-first day of July 1890.
CRUIKSHANK & FAIRWEATHER,
62, Saint Vincent Street, Glasgow, Agents.