Two Manuals can be Applied to One Sound-board.
Year: 1886

page_text: Two Manuals can be Applied to One Sound-board.
I WALTHER ALBERT HEINRICH DRECHSLER of 53 Percy Road Shepherds Bush in
the county of Middlesex Organ Builder do hereby declare the nature of the said
invention for IMPROVEMENTS IN PNEUMATIC SOUND-BOARDS OF ORGANS WHEREBY
TWO MANUALS CAN BE APPLIED TO ONE SOUND BOARD, and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement:-
The essential features of this invention are 1st to get a quick repetition and 2nd
to make the leather pallets or valves of the sound board perfectly air tight.
Fig. 1 of the accompanying drawings represents the pneumatic sound-board seen
in side view, the action being shown half size, the key supposed at rest, A, A, A, are
the chests in the sound board filled with pipe wind, the stops being understood to
be drawn out.
The wind from the chest B, is from 1 to 2 inches higher pressure, and as
represented in the drawing is pressing through the hole m, channels C. D. D, and
holes E. E. E. and acting on the leather pallets or valves F. F. F. presses them
against the holes G. G. G. keeping the pipe wind in the chest A.
As soon as the key is pressed down, the wind from the chest beneath the clavier
or key board (not shown in the drawings) passes through the tube I to the
buffer K, lifting up the felt pallet L.
This pallet closes the hole m, and opens the hole n, thus shutting off the high
pressure from the chest B; and the channels C. D. E. then communicate with the
external air only.
The pipe wind in A instantly forces the leather pallets F, towards the
holes E. E. E, and enters the pipe through G. H.
0.0. O. are upper, and R. R. R. the bottom boards. To get a quick repetition it
is imperatively necessary that the mouth of the hole E should occupy a position
exactly opposite the flat part S.
The leather of the pallets must be soft, and to make it air tight must be rubbed
with grease. It would not matter if any parts of the sound board occupied any
other position.

page_text: Fig. II represents the draw-stop action half size, constructed on the same
principle.. A is a box with pipe wind, B containing the higher pressure, communi-
cating through m, C, with B, which latter is covered with the leather pallet F.
By pulling out the draw stops, the wind is admitted into the tube I, and to the
buffer K, by this means lifting up the pallet L, this latter closes the hole m, and
opens the hole n, thus the high pressure is shut off, and in n. C. B, is the atmo-
sphere merely. The pipe wind in A then forces the pallet F, towards C, and admits
the wind through G, and H, into the box A, Fig. 1. The above mentioned arrange-
ment refers to a single manual.
Fig. III, shews a full sized apparatus which can be adapted to the sound-board
when required for two manuals. It is to be placed between the bottom board R,
Fig. 1, and the channel D, any of the holes E Figs. I and III, are then brought
into communication, and the channels D, Fig 1, with the hole D Fig. III as well, as
the hole B is intended to communicate with another similar channel to D Fig. 1,
but belonging to the second clavier or key board.
A and C Fig. III are chambers for the draw-stop action, and can be filled
with high pressure wind, or simple atmosphere through a pallet not seen in the
drawings.
If the chamber C, Fig. III is open to the atmosphere (draw stop on) the leather
pallet F, Fig. III will close the hole L, because the high pressure comes through the
channel D, Fig. 1 into the hole D Fig. III.
As soon as the wind in D is exhausted (which is also occasioned by touching the
key) the high pressure on the other side will close the pallet H, and open that G,
thus the pallet F, Fig. 1 will be forced back by the pipe wind, because there is an
exhaust through E Fig. 1. E. G. D. Fig. III, D. C. and n Fig. 1.
When the draw stop is off (vide Fig. III to the right) the pallet will close the
hole B, whether the key is touched or not, and the high pressure will still be
in H. E Fig. III. keeping the pallet F Fig. 1 closed. As soon as the key is touched,
and the draw stop is pulled out the high pressure is exhausted through A. K. H. E
Fig. III, and E Fig. 1, and the pipe wind will act at once as before.
The two pallets G. and H Fig. III, are connected with a sticker m, which keeps
one pallet always open allowing a free return to the wind."
The same arrangements must be applied to each stop, that is required on the
second manual.
In small organs where the distance of the keys from the organ is short, the high
pressure can supply the channel D Fig. 1, direct through the tube I, so that the
buffer K, pallet L, and chest B, Fig. 1 are done away with.
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
1st The method of getting a quick repetition by having the mouth of the hole E
exactly opposite the flat part S.
2nd Making the leather of the pallets air tight by rubbing grease into them;
Dated this 24th day of May 1886.
A. C. HENDERSON,
Agent for Walther Albert Heinrich, Drechsler