AN IMPROVED PNEUMATIC LEVER FOR ORGANS OR WIND INSTRUMENTS
Year: 1885

page_text: I HENRY THOMAS WEDLAKE trading as H. Wedlake of 8 Berkeley Road,
Regent's Park in the county of Middlesex Organ Builder do hereby declare the
nature of my said invention for AN IMPROVED PNEUMATIC LEVER FOR ORGANS
OR WIND INSTRUMENTS to be as follows:-
The object of my invention is to provide a pneumatic lever for organs and other
wind instruments that shall be extremely efficient and sensitive and of which a
large number can be placed in a comparatively small compass whereby these
pneumatic levers can be applied in positions where the usual and ordinary ones at
present in use cannot be utilized and at the same time as these my pneumatic
levers are very simple in construction the same will be much less costly than the
present appliances..
1.
To carry out this object I form and construct this my pneumatic lever in the
following manner. A fixed upper board is provided of the required size and shape
and under one end of this board is formed a small chamber divided by an horizontal
partition. A lower board is hinged or pivotted to this chamber or to the underside
of the fixed upper board and the edges of these two boards are joined by a strip of
flexible material and thus these two boards and the joining strip constitute the
bellows required. A passage of communication is made from the space inside the
bellows to the chamber aforesaid above the horizontal partition therein and in this
said partition is an aperture governed by a suitable valve. A large aperture is
also made in the fixed upper board above this valve which is partially closed by a
piece of flexible material leaving a rather large aperture in the centre thereof the
edges of which may be stiffened by a ring of stiff material secured to the said
edges. A rod passes through and is secured to the valve aforesaid the upper end of
which is attached to a long flat spring secured on the upper surface of the fixed
upper board while any suitable metallic or other spring can also be secured between
any fixed point above and the top of the valve rod to assist in forcing the said
valve down on its seat. The lower end of the rod is attached to or actuated by a
lever the other end of which is connected with the key. Another aperture is also
made through the fixed upper board at or near the other end thereof which is
governed by a binged or other valve on the lower side whereof is a stud and a
cushion is formed on the lower hinged board immediately below the same.
suitable rod or other appliance is secured to or actuated by the end of the lower
A

page_text: binged board through and by which rod or other appliance the action required of
this pneumatic lever is effected. This apparatus is enclosed in a wind chest
through the side or casing of which is made an aperture communicating with the
chamber aforesaid below the horizontal partition therein and the action of this my
pneumatic lever is as follows.
When the wind chest is filled with air at the proper desired pressure the valve
is forced down on its seat in the partition in the chamber and the air, finds its way
through the aperture in the fixed upper board into the upper division of the
chamber and thence into the bellows expanding the same and depressing the
lower hinged board. When the key is depressed the lever raises the valve off this
seat and presses it against the piece of flexible material which partially closes the
aperture in the fixed upper board above which therefore forms another and flexible
seat for the upper surface of the valve preventing any more air from entering from
the wind chest and the long flat spring aforesaid acts as a guide for this motion of
the valve. The air therefore rushes out of the bellows through the aperture in the
horizontal partition into the lower division of the chamber and thence out of the
wind chest through the aperture in the side or casing thereof and the pressure of
ain in the said wind chest immediately raises the lower hinged board of the bellows
producing through and by the rod or other appliance the aforesaid required action
and to obviate any noise or jarring by this collapse of the bellows as the said lower
hinged board rises close to the fixed upper board the cushion aforesaid comes in
contact with the stud on the hinged or other valve slightly raising the same and
allowing some air to enter the bellows and then when the two boards are in close
proximity the said cushion acts as a valve and entirely closes this aperture pre-
venting any more air from entering the bellows until the key is released when the
valve in the chamber is forced down on its seat in the horizontal partition air is
admitted and the bellows again is expanded and all is in readiness for the next
depression of the key.
This apparatus which constitutes my pneumatic lever can be placed in any
required number in the wind chest through the side or casing of which is made an
aperture communicating with the lower division of the chamber of each apparatus
and each of the said apparatus would be secured therein by their fixed upper
boards or otherwise in any arrangement that may be convenient and suitable and
they can be placed so close together that a large number can be fitted in a com-
paratively small wind chest as is required.

page_text: An Improved Pneumatic Lever for Organs or Wind Instruments.
HENRY THOMAS WEDLAKE trading as H. Wedlake of 8 Berkley Road Regents
Park in the County of Middlesex Organ Builder, do hereby declare the nature
of my invention for AN IMPROVED PNEUMATIC LEVER FOR ORGANS OR WIND
INSTRUMENTS and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :—
The object of my invention is to provide a pneumatic lever for organs and other
similar wind instruments that shall be extremely efficient and sensitive and of
which a large number can be placed in a comparatively small compass whereby the
pneumatic levers can be applied in positions where the usual and ordinary ones
at present in use cannot be utilized and at the same time as these my Pneumatic
levers are very simple in construction the same will be much less costly or may be
so than the present appliances.
In order that my invention may be clearly understood and carried into effect
I will now proceed to more particularly describe the several parts with the aid of
sectional drawings.
The same letters of reference indicate corresponding parts in all the corresponding
figures. In the said drawing Fig. 1 illustrates a transverse section through a box
or chest hereafter called the wind chest in which are fitted my improved pneumatic
levers or bellows. Fig. 2 is an enlarged section of one of my improved pneumatic
levers showing how I apply my improved double faced valve (which may be covered
with leather or any other suitable material) for the purpose of opening or closing
the passages which admit the ingress of compressed air to the inside of the bellows
and the egress of compressed air to the atmosphere.
Fig. 3 is another view of the said valve shewing in transverse section my
improved flexible seating together with the wire bridge I prefer to use for the
purpose of obtaining a support for the wire spring which keeps the valve in its
required position but I may sometimes apply the necessary pressure to the valve
by other means.
Referring to Fig. 2 A is a fixed upper board supported in any convenient manner
within the wind chest C preferably attached to the front-side and supported at the
opposite end by a bar or bearer B which may extend from end to end of the said
wind chest but it may be attached to the opposite side if necessity arises. The
size or shape of the said upper board which forms a portion of my improved
pneumatic lever deing discretionary but preferably made rectangular. At that end
where the upper board is secured to the side of the wind chest is a valve chamber D
the lower side of which or adjacent thereto is hinged or pivoted another
upon
board F the edges of which when joined by any flexible material to those of the
upper fixed board A constitute a bellows or pneumatic lever the said lower board F
being so hinged that it may coincide with the upper one A the position during
coincidence being shown in the second lever G Fig. 1.
An open passage of communication is left between the space H inside the
bellows and the valve chamber D at or about the point where the lower board
hinges at K

page_text: Two other ports or passages are provided one in the lower side of the valve
chamber at E hereinafter called the exhaust port and another at E' in the upper
side of the valve chamber which is formed by the fixed board A.
Each of these ports may be made circular or otherwise as may be desired.
Within the said valve chamber D is the double faced valve L which travels
vertically between the two ports E and E¹ the port E being provided with a flexible
seat in accordance with my claim contained in the patent granted to me No. 2666
of this present year.
By referring to Fig. 2 it will be seen that the aperture in the fixed board A which
forms a portion of the valve port E¹ is larger than that in the lower side of the
valve chamber at E but the desired area is obtained by reducing the opening in
the flexible material M which forms the seating for the said valve L the edges of
which seating which may be of soft leather are stiffened by a ring N of stiff material
which may be of cardboard secured to the inner edge of the said flexible seat.
The valve L is provided with a central spindle O the upper end of which is
attached to the flat spring P which said spring is secured to the upper surface of
the fixed board A at P¹ and the means I use to keep the valve L down to its lower
seat closing the exhaust port is by the pressure of a suitable spring bearing upon
the top of the valve spindle. O at S which spring is held in position by a wire
bridge R Fig. 3 which provides the fulcrum for the upper arm of the spring Q.
The lower end of the valve spindle is actuated by the upward pressure of the
lever T centered at U the opposite end being connected by a tracker to the key as
shown at V in Fig. 1. At the opposite end of the bellows is an aperture W
governed by a valve X which for convenience is held by the elongated end of the
flat spring P but it can be held upon its seat in any other suitable manner.
Immediately below the valve X is a stud Y and cushion Y₁ secured to the hinged
lower board F and consequently moveable with it. The Bar Z which moves with
the lower board F (being secured to it) is the means by which I transmit motion
through a tracker to the sound board valve. Thus it will be understood that when
the box or chest C is charged with wind under pressure and the valve L forced
down upon its lower seat closing the exhaust port E the wind necessarily finds its
way into the bellows as well as surrounding its external surfaces the whole
apparatus being consequently in equilibrium and the several parts comprising the
pneumatic lever are in the position indicated in Fig. 2. that is to say the key and
Bound board valve are at rest.
Upon the key being depressed by the finger of the organist the rocking bar 2
brings down the outer end of the lever T the opposite end of the same lever lifts
the valve L from its lower seat and presses it against the flexible material of which
the valve seat M is formed, hence the supply port E' is closed and the exhaust
port E is opened the former cutting off the supply of compressed air to the inner
chamber of the bellows and the latter causing the compressed air to escape to the
passage J below the valve chamber to the outside of the wind chest reducing the
pressure of air within the bellows to that of the atmosphere and as the external
surfaces of the pneumatic lever or bellows are surrounded by wind which is pressing
upon them and the inner chamber of the said bellows is devoid of such pressure
the air which remains inside is consequently squeezed out by the superabundance
of pressure which surrounds the external surfaces resulting in the movement of the
lower hinged board F until it coincides with the upper fixed board A and as the
bar Z has a simultaneous movement with the board F the tracker which it carries
transmits a corresponding movement and opens the sound board valve.
In order to prevent any noise occurring by the sudden collapse of the bellows
the stud Y comes in contact with the valve X immediately before complete
collapse has taken place and by slightly lifting it from its seat a small portion of
compressed air is admitted in order to form an elastic cushion and when the two
boards A and F are in close contact the flexible cushion Y¹ acts as a valve and
effectually closes the aperture thereby preventing any more compressed air entering
the bellows until the key is released. Upon the key being released the valve L

page_text: falls or is pressed down upon its lower seat the exhaust port thereby being closed
and the supply port opened compressed air again passes from the wind chest into
the inner space of the bellows resulting in its expansion and the consequent return
of the parts connected there with to their normal position.
Hence it will be seen that my improved pneumatic lever is entirely self contained
the only connections required being those with the lever T one end of which lever
is connected with the under side of the valve spindle and the other end of the said
lever to the tracker which is attached to the rocking bar 2 or key action.
I am also enabled to considerably reduce the expense of those parts used in
transmitting movement to the sound board valves first by the employment of less
skilled labour than has previously been required and secondly by the greatly
reduced compass of space in which I am enabled to compress my improved
pneumatic levers it only being necessary to allow a trifling clearance between
each bellows both vertically and longitudinally so that I can pack all the pneu-
matic levers for an organ of ordinary dimensions into a comparatively shallow
box a feature of considerable importance where height cannot be obtained; further
my improvements enable me to produce a sensation of real grip such as no other
pneumatic has ever given at once establishing a sympathetic bond of union between
artiste and mechanism, direct contact in fact with the sound producing apparatus.
I am also enabled to produce an organ in which the most rapid repetitions of a·
single note may be played with facility and such as have been hitherto thoroughly
impracticable upon organs fitted with the ordinary pneumatic action.
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 use of a Pneumatic lever within an air tight wind chest the action of
which is directly reverse to what has been previously adopted viz. that it is
inverted, the result being that when a key is depressed by the organist I allow the
air which is in the Pneumatic lever to escape and cause thereby an immediate
collapse of the bellows which brings with it the tracker opening the sound board
valve in contradistinction to the method which has previously been adopted viz. the
inflating and opening of the said Pneumatic lever when the key has been depressed,
by this means I secure over a third more power to each lever than has hitherto
been obtained and in consequence of this additional power I am enabled to save
considerable expense in the construction of organs as I am able to use the bellows
of the ordinary instrument instead of being compelled to add an auxilliary bellows
usual in dealing with the ordinary pneumatic action.
2nd The construction and application of a double faced valve fitted to and acting
within a pneumatic lever which valve shall open an exhaust port and in doing so
close a supply port when the key is depressed and which shall close the same
exhaust port and in doing so open a supply port immediately upon the key being
released.
3rd The construction and application of an improved flexible valve seat made of
any flexible material the aperture through which shall be somewhat smaller than
that which is made in the board upon which the said flexible valve seat is secured
in order that the said seat may be free to bend when the valve is pressed against it
and which shall have a ring of stiff material having an aperture equal to that of
the said flexible material the inner edges of which shall be secured together, the
other edge of the said stiff material being left free in order that the flexible seat
may bend freely on one side but which stiff material shall prevent the external
pressure from causing the flexible seat to follow the valve any further on its travel
than the point at which the said flexible material becomes level with the board
upon which it is held.
4th The application of a check valve fixed in any convenient position upon the
pneumatic lever which shall be made to open just upon the complete collapse of the
bellows and which shall be so actuated that it will admit just sufficient air to

page_text: produce an elastic cushion between the two said boards together with the use of a
flexible cushion which shall effectually close the aforesaid valve opening directly
after the cushion of air has been admitted and secured upon the opposite board to
that in which is the opening for the admission of the cushion of air.
5th The application of a full set of Pneumatic levers consisting of 56 notes into
a wind tight chest the compass of which shall be sixteen inches in height or there-
about and an average width between first and last arms equal to that of the key
board of an organ the said pneumatic levers being so self contained that the chest
can be supplied ready for attachment in any organ already constructed and which
shall require no more connections than those to the trackers leading to keys and
roller board.
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