Improvements in Audible Signal-apparatus.
Year: 1888

page_text: Date of Application, 11th Sept., 1888
Complete Specification Left, 13th Nov., 1888
Complete Specification Accepted, 31st Dec., 1888
Improvements in Audible Signal-apparatus.
A communication from 'HERMANN_EDUARD PFANNENSTIEL, of Danzig, in the German
Empire, Mechanic.
I ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention to be as follows:-
The present invention relates to improvements in sounding signal-apparatus in
which metal reeds are vibrated by means of compressed air, thus producing a powerful
uniformly strong sound which is carried a great distance. The air is drawn in and
compressed by an air pump worked by hand.
The air drawn in through suitable valves when the piston is drawn back; is
compressed when the piston is moved forward and is forced into a wind chest through
a funnel shaped opening. In the wind chest are mounted preferably three coupled
steel or other reeds or blades which are vibrated by means of the compressed
air and produce the sound by vibrating near the edges of forked plates mounted
in the wind chest and between the arms of which the said reeds vibrate. The
sound travels into the outer air through a funnel shaped tube. The top blade is
slotted so that the compressed air can also act upon the lower one. The forward
stroke of the piston is made in shorter or longer intervals according to the code used
for representing the different letters of the alphabet. The wind chest and funnel
shaped tube are protected by a surrounding tube.
Underneath the wind chest is arranged an air space into which the compressed air
passing between the vibrating blades and the surrounding plates enters and prevents
the vibrating reeds from coming in contact with the wall of the wind chest.
Dated this 11th day of Santamber 1888

page_text: A communication from HERMANN EDUARD PFANNENSTIEL, of Danzig, in the German
Empiro, Mechanic.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E. 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 present invention relates to improvements in sounding signal-apparatus in
which metal reeds are vibrated by means of compressed air, thus producing a powerful
uniformly strong sound which is carried a great distance.
In the accompanying drawings:-
-
Fig. 1 represents a vertical section of the whole apparatus.
Fig. 2 represents a vertical section of the wind chest and reeds.
The air is drawn in and compressed by an air pump A worked by hand.
The air drawn in through suitable. valves v when the piston K is drawn back; is
compressed when the piston is moved forward and is forced into a wind chest W
through a conical tube T. In the wind chest are mounted preferably three coupled
steel or other reeds or blades F F which can be connected together by screws or
equivalent and are vibrated by means of the compressed air and produce the sound by
vibrating near the edges of forked plates P mounted in the wind chest and between
the arms of which the said reeds vibrate. The sound travels into the outer air through
a funnel shaped tube S. The top reed is slotted so that the compressed air can also
act upon the lower one. The forward stroke of the piston is made in shorter or
longer intervals according to the code used for representing the different letters of the
alphabet. The wind chest and funnel-shaped tube are protected by a surrounding
tube or casing H.
Underneath the wind chest is arranged an air-space L into which the compressed
air passing between the vibrating blades and the surrounding plates enters and
prevents the vibrating reeds from coming in contact with the wall of the wind
chest.
"
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. In an audible signal apparatus the combination with an air pump A of the
conical tube T and wind chest W substantially as described and illustrated in the
accompanying drawings.
2. In an audible signal.apparatus a series of reeds such as fF F', which may be
connected together and the upper, one of which is formed with a slot to allow the
compressed air to act.better on the lower ones substantially as described and illustrated
in the accompanying drawings.

page_text: 3. In an audible signal apparatus the combination with the reeds fF F¹ of forked
plates such as P between the arms of which the reeds vibrate for producing the sound
substantially as described and illustrated in the accompanying drawings.
4. In an audible signal apparatus the air space Ĺ for the purpose of preventing
the vibrating reeds from coming in contact with the wall of the wind chest
substantially as described and illustrated in the accompanying drawings.
5. The complete audible signal apparatus substantially as described and illustrated
in the accompanying drawings.