Improvements in Organs.
Year: 1894

page_text: Date of Application, 31st Mar., 1894-Accepted, 2nd June, 1894
COMPLETE SPECIFICATION.
Improvements in Organs.
I, THOMAS CASSON, of 71 Callcott Road, Brondesbury, in the County of
Middlesex, Bank Manager, 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 :-
My invention relates to certain arrangements in pneumatic organs whereby I
facilitate the combinations of pedal stops or couplers with manual stops and the
separation of melody on one manual from harmony performed on another.
In order to facilitate the combinations of pedal stops or couplers with manual
stops I employ apparatus such as I shall describe referring to Figs. 1 to 6 inclusive
of the accompanying drawings.
A A Fig. 1 is a side view of the slides or rods for manual stops all of which for
each manual are arranged on one plane. On these I fix blocks F of cam form, and
beside them I mount transverse fans B, C and such others as may be required for
various combinations, each fan being capable of rocking on an axis, and having an
arm or arms connected to slide valves D each of which governs two passages G
and H from a wind chest E there being one chest E for each manual division.
These passages are connected by tubes or grooves to a valve box Fig. 2 containing
check valves P. There are for each pedal stop and coupler two of the valve boxes
shewn in section at Fig. 2 the one in each case communicating with the passage G
Fig. 1, the other with the passage H, and from the two valve boxes pipes g and h
lead to the valve arrangement shewn in section at Fig. 3. The pipe 9 communicates
with two pneumatic levers J and L, the pipe h with one pneumatic lever K. The
levers J and K are connected respectively to valves j and k situated in a wind
cheste over passages leading the one into a pneumatic lever M, the other to the
case containing M, which is connected to the rod or slide N for a pedal stop or
coupler. When, as shewn in Fig. 1, the valve D for any one of the manuals makes
communication from E to G, wind passes to the valve box Fig. 2 and thence by g
to act on J and L, the valve of J being thus raised, while that of K is prevented
from rising, and the pneumatic lever M is thus disturbed and moves the slide N
bringing the pedal stop or coupler into action. Should the valve D belonging to
any manual be moved over so as to open G to the air and bring H into com-
munication with E, then wind will pass by H to a check valve box like Fig. 2 and
thence by pipe to pneumatic lever K opening the valve connected to it and
thereby causing M to collapse and move back the slide N. If when the pipe / is
thus conveying wind to K, in consequence of the movement of the slide valve D of
any manual, the pipe 9 is also conveying wind to J owing to the other position
of D belonging to another manual, then K is prevented by the pressure on L from
acting so as to cause the back movement of N, the pedal stop or coupler being thus
retained in action. It is to be understood that the wind chest E is only charged
by the performer touching a button or its equivalent of which there is one for each
manual whereby a valve is opened to convey wind to E. This is the only operation
required on the part of the performer to bring into action the pedal stops or
couplers appropriate to the manual.
The valve D of Fig. 1 instead of governing two ports G and H may govern
only one, G, the port H and conduit à being omitted. In the position shewn in
Fig. 1 it charges G and g to bring the stop or coupler into action: when it is
moved to the right it opens G to the outer air by which the stop or coupler is taken
out of action, the valves for the pneumatic lever M being arranged as shewn in

page_text: section at Fig. 4. In this case the chest e Fig. 4 has to be charged and depleted
simultaneously with any of the chambers E Fig. 1.
If one of two manuals be augmented by coupling another to it, the stud or its
equivalent, which I call +6
a pedal help," of the manual thus augmented should
bring into action the pedal combination of both though that of the coupled manual
must continue in action for only its own combination. For this purpose I employ a
valve arrangement shewn in section at Fig. 5. The pneumatic current which
effects the coupling of the manuals supplies also a chamber a. The current
charging the chamber E of the augmented manual charges also a chamber b.
In a and b are valves pendent from a beam in a chamber whence a conduit
furnished with a check valve goes to charge the chest E Fig. 1 of the coupled
manual. If now either a or b (Fig. 5) be separately charged no action can result
because the valve in either will close; but when a and b are both charged wind will
pass either or both valves to f and thence to the chest E Fig. 1 of the coupled
manual.
If one or more divisions of stops be attachable to one manual only, the "pedal
help" of that manual should bring into action the appropriate combination for the
division then attached. To effect this I employ a valve arrangement such as is
illustrated in section at Fig. 6. The pedal help by conduit charges a chamber a,
while b and c are respectively charged by the currents which attach the divisions
to the manual. Balanced valves like those in Fig. 5 are suspended from chambers d
and f, whence proceed conduits with check valves to the chests E (Fig. 1) of the
two divisions. Concurrent charging of a and b will charge the chest E (Fig. 1) of
the one division and the concurrent charging of a and c will charge the chest E
(Fig. 1) of the other division.
I have shewn the arrangements of Figs. 5 and 6 combined as they should be
when that of Fig. 6 is in relation to a coupled manual.
Thus the "pedal help" of any manual will always bring into action the correct
pedal combination of stops and couplers, automatically selecting and coupling them,
rectifying any contradictory positions and displaying the combinations, the draw
stops being nevertheless perfectly free for ordinary manipulation.
It is sometimes desirable that while a piece of music is performed with its full
harmony on one keyboard of an organ the melody alone without the harmony should
be sounded by the pipes appropriated to another keyboard. This may be done in
two ways. Firstly by applying the apparatus shown in Figs. 7 and 8 to the key
action, in which case the melody will be taken by the pipes of the keyboard played
upon while the harmony will be supplied by those of another keyboard coupled to
it, or secondly (which is preferable) the apparatus may be applied to the coupling
action, in which case the harmony will be taken by the pipes of the keyboard
played upon, while the melody will be taken by those of the keyboard coupled to
A third method is when (as in the "Ventil system") two or more divisions are
attachable to one manual only in which case one division can take the full harmony
while the other takes the melody only. The apparatus is of the same form in each
instance and is described for the second method.
it.
In order to effect this separation of melody from the harmony I employ an
arrangement of valves such as that shown in section in Fig. 7 along the line OO
of the plan shown in Fig. 8. U is a pneumatic lever worked directly electrically
or otherwise by the depression of the key on which the harmony is performed;
this pneumatic lever extends diagonally from the line of the chamber for
one key to the line of the chamber for the next lower key. When it is
distended it opens valves T and Y and closes V and X. Thus wind from a
charged wind chest R, passes by S to the pneumatic lever which causes a
note to sound on a second keyboard. Each note has a chest R, but only the
chest for the note of highest pitch is directly charged, the chest for the next
lower note being charged through a diagonal passage W, and so on throughout
the compass or any desired portion of it. As when the lever U is distended the
valve X is closed, it follows that only that note of the harmony which has the

page_text: highest pitch is sounded, the valve Y allowing escape from the pneumatic lever of
any lower note previously sounded. Z is a chest communicating with all the valve
openings Y. Should it be desired to prevent the separation of the melody as above
described, the chest Z may be charged with wind whereby all the valves Y are
free to open, charging all the chests R, and thus all the notes, whatever their
pitch, will be sounded in the usual way.
If the apparatus be applied according to the first named way the duct S would
lead to the pneumatic lever of the action belonging to the keys struck, instead of
to that of another keyboard. I have described this arrangement applied to cause.
only the notes of highest pitch to sound. Obviously by arranging that only
the wind chest R of the note of lowest pitch is directly charged, the chest of the
next higher pitch being charged from it and so on throughout the compass or any
desired portion of it, the bass melody can be similarly separated from the general
harmony.
The valves T and V, X and Y may be lifted by direct key action instead of by
the pneumatic lever U.
I have described the valve arrangements in all the foregoing figures as being
worked by plenum or wind under pressure; by suitable inversions they may be
worked by exhaust or vacuum.
It must be understood that pneumatic relays may be inserted at any point and
that any of the pneumatic levers may be charged and depleted by electro-
pneumatic agency and may themselves be used for making electric contacts. Also,
that where a drawstop is referred to, the term applies whatever exterior accessory
be employed to draw and close it, such as a stop, key or pedal.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. In combination with the slides or rods of the manual stops of an organ cam
blocks arranged thereon acting on rocking vanes connected to slide valves, passages
controlled by these valves, tubes, check-valves, pneumatic levers and valves,
arranged to operate the rods or slides of pedal stops or couplers substantially as
and for the purposes herein set forth and as illustrated by Figs. 1 to 6 inclusive of
the accompanying drawings.
2. In combination with the key and coupling actions of two divisions of an organ
or set of wind chests and valves arranged to operate the gear for sounding the notes
in such manner that on one division the full harmony is sounded while on the other
only the note of highest or lowest pitch is sounded substantially as described with
reference to Figs. 7 and 8 and for the purpose set forth.
Dated this 31st day of March 1894.
ABEL & IMRAI,
Agents for the Applicant..