Year: 1897

page_text: I, GERARD JOHAN PIETERS, of Vijgendam. No. 20, Amsterdam, in the Kingdom
of Holland, Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to a construction of foghorns having reeds worked by
steam or other elastic fluid under pressure, whereby I obtain tones purer and
stronger and capable of being heard at a greater distance than the tones of
horns as they are usually constructed.
For this purpose I introduce the working fluid into the chamber containing
the reed in a stream parallel to the reed and of width equal to that of the reed,
the inlet being of rectangular shape, having its length equal to the width of the
reed and its breadth approximately equal to the range of vibration of the free
end of the reed. The reed itself has its end which is farthest from the fluid
inlet securely fixed to the flattened face of the outlet tube there being a hole
through this face of about the same area as that of the inlet to the chamber,
this hole being somewhat narrower than the reed and in the form of a rectangle
on which is superposed a triangle or curved segment.
The outlet tube which has a bend terminating in a trumpet mouth is made
in two parts jointed together in such a manner that the one part can be turned
on the other as an axis, so as to direct the trumpet mouth as may be desired.
Preferably two horns sounding notes of different pitch are mounted side by
side with valves by which fluid can be admitted to the one or the other. I make
these valves preferably in the form of screw stop valves the handle which works
them having its stroke limited by a stop adjusted so as to restrict the flow of
fluid to that which is found by trial to produce the purest tone.
Two or more
horns having notes of different pitch may be used for signalling purposes.
In some cases I employ for the horn a free reed vibrating between two equal
chambers which communicate with the trumpet tube.
The chamber containing the reed is provided with an outlet governed by a cock
or valve, by which water of condensation can escape, or steam can be allowed
to issue so as to reduce the pressure in the chambers as may be desired.
T : 100-1 dos at Cantambon 1907
ABEL & IMRAY,
Agents for the Applicant.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Fog Horns.
1. GERARD JOHAN PIETERS. of Viigendam No. 20. Amsterdam, in the Kingdom

page_text: what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
This invention relates to an improved construction of fog-horns having reeds
worked by steam or other elastic fluid under pressure, whereby, with a compara-
tively small expenditure of power I obtain sounds purer and stronger and capable
of being heard at greater distances than the sounds of fog horns as they are
usually constructed, the sound being given out in such manner that the position
of the fog-horn can be accurately determined by the strength thereof.
This object is fulfilled according to the present invention by effecting the vibra-
tion of the reed, not merely by the pressure of the steam, as heretofore, but also
by utilising the velocity of issue or the vis viva of the steam for this purpose,
and by admitting only a definite quantity of steam, determined by experiment.
In order to utilize the velocity of the steam, the arrangement of the fog-horn
is such, that the reed is situated directly in front of the steam inlet, the latter
being necessarily inade of a rectangular cross section, such that the length of
the rectangle corresponds to the width of the reed, while the width of the inlet
corresponds with the range of vibration of the reed.
These proportions are of importance, not only because thereby the entire
steam jet is led directly against the reed and is consequently better utilised, but
also, because all particles of steam that might rise uselessly at the side of the
reed would only increase the steam pressure in the cylinder, in which the mouth-
piece carrying the reed is arranged, whereby the vibration of of the reed would
be reduced and even might be entirely prevented.
This defect is also prevented in the improved construction, by providing the
cylinder with an escape valve; experiments have shown that this also has a
most marked influence upon the purity of the tone.
In order to prevent the possibility of the fracturing of the reed under the
increased strain to which it is subject by the improved construction, a peculiar
configuration is imparted to the opening of the mouth through which the steam
escapes under the reed, such configuration being made to correspond to the form
of the steam jet, the reed being enclosed between side ribs.
By this means the steam jet is made to act in an undivided manner only on
the free end of the reed and a fracturing of the latter, such as occurs when the
steam jet tends to force the reed away near its weakest point usually in the
middle is avoided.
For insuring a sharper sounding of the reed, this is fixed, not merely by
screws as heretofore, but through the medium of an inelastic intermediate plate.
In order to insure that only a definite quantity of steam shall pass to the
reed, as above stated, and thus to prevent the occurrence of too great a com-
pression causing interference with the vibration of the reed in the cylinder not-
withstanding the provision of the escape valve, the spindle of the inlet valve
is provided, for example, at the handle, with a projecting arm which after turning
the spindle through a certain angle, is made to strike against a stop on an
adjustable disc, so as to prevent the further rotation of the spindle and conse-
quently the further opening of the valve.
By the above described means the greatest possible extent of vibration of the
reed, and consequently the greatest amplitude of the sound waves is obtained,
resulting in a very sharp pure sound, which when led off through a horn will
travel to great distances even against a strong wind, and which, if the upper part
of the horn be gradually turned round, renders it still more easy to determine,
from the strength of the sound, which is greatest in the axial line of the fog-
horn's mouth, the exact point at, or direction in which, the fog-horn is situated.
The length of the horn should be so made that the vibrations of the reed work
in unison with the vibrations of the column of air in the horn, that is to say
the horn ought to sound with the reed.
It is of importance that only the upper part of the horn should be made to turn,
and not the entire apparatus, because in the latter case an interference in the

page_text: production of the sound might ensue, which does not occur in the former
case.
On the accompanying drawings is shewn by way of example one construction
of the improved fog horn.
Figs. 1, 2, 3 and 4 shew respectively a front view of the complete mouth
piece D, a front view of the mouth piece without the reed, a side view, and a
vertical section of the same.
The mouth piece D has a peculiarly shaped escape opening d with rectangular
lower end and pointed equilateral triangular upper end, over which the reed g
is secured by means of screws and an intermediate plate f.
The Figs. 1, 2 are plans, and Figs. 3 and 4 show the mouth piece upside
These ribs ought to
down with the arrangement of the side ribs p q and rs.
enclose the reed as much as possible without disturbing the vibration and they
ought to be prolonged as shewn in the drawing up to the base of the triangle
in order to further prevent the steam from forcing itself a way under the reed.
The mouth piece is suspended by its upper rim a in the cylinder C, of the
fog horn as shewn in Figs. 5 to 9, of which Fig. 5 shews a vertical section of
the fog horn, Fig. Ga section at right angles to Fig. 5, Fig. 7 an elevation
Fig. 8 the mouth of the horn and Fig. 9 a cross section. The mouth piece is so
arranged in the cylinder C that the lower edge of the reed is exactly over the
steam inlet 11 of the valve casing A, as shown at Figs. 5 and 6. The regulation
of the steam jet is effected by the valve 1 with spindle 2 handle 3 arm 6 and
disc 5 with stud 4 Fig. 7. The cylinder Chas, as shewn at Figs. 5 and 6, an
outlet at operating as an escape valve.
Over the mouth piece 1) is fixed upon the cylinder C the funnel-shaped tube E,
and on the cylindrical upper end of this is fitted loose the mouth of the foghorn F.
The rotation hereof is shewn effected by way of example by means of a hand
wheel o, bevil wheels b¹ b¹, spindle carried in the base plate G and the cross-
head K supported by standards H, and toothed wheels m, l.
As with the improved foghorn the pitch of the sound can be accurately adjusted,
it is possible to employ it as signalling apparatus, in particular if two foghorns
with notes of different pitch be employed. Such two foghorns may either be
separate or they may be combined in one apparatus.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:
1. A foghorn wherein, for the purpose of obtaining a clear pure sound of
increased penetrating power the reed is actuated not only by the pressure of
steam but also by the vis viva thereof, said foghorn being characterised by the
arrangement of the reed directly over the steam inlet opening which has a
cross section corresponding to the form and size of the space traversed by the
end of the vibrating reed, a complete utilisation of the steam being thereby
obtained and a diminution of the vibrations of the reed, resulting from excessive
pressure in the cylinder prevented, substantially as described.
2. In a fog horn such as is referred to in the preceding claim, a mouth piece
with escape opening having a configuration corresponding to the form of the
steam jet and having ribs enclosing the reed nearly up to its point for the
purpose of causing the steam to act with its full force only on the free end or
point of the reed, substantially as described.
3. In a fog horn of the kind referred to in the first and second claims, the
combination with the spindle of the inlet valve of a handle which, after being
turned through a certain angle, is brought in contact with a stop on an adjust-
able disc or equivalent device, for the purpose of always admitting only a definite
quantity of steam to act upon the reed, substantially as described.
4. In a foghorn of the kind referred to in the preceding claims, mounting the
upper part or mouth of the horn rotatably upon the fixed lower part, for the

page_text: purpose of transmitting the strong sound emitted from the horn in different
radial directions, so that the position of the fog horn can be readily determined
by observing the direction of the greatest strength of the sound given out.
5. In combination with the cylinder and mouth piece located therein, the
arrangement of an escape valve for the purpose of getting rid of any excess
pressure in the cylinder that would interfere with the vibration of the reed and
in consequence has to be located just at the point of the vibrating reed sub-
stantially as described.
6. The combination for signalling purposes of several of the apparatus referred
to in the preceding claims.
Dated this 22nd day of July 1898.
ABEL & IMRA Y,
Agents for the Applicant.