IMPROVEMENTS IN AUDIBLE FOG AND OTHER SIGNALS
Year: 1876

page_text: LETTERS PATENT to John Richardson Wigham, residing at Capel Street, in the
City of Dublin, Ireland, Gas Engineer, for the Invention of "IMPROVEMENTS
IN AUDIBLE FOG AND OTHER SIGNALS."
Sealed the 9th September 1876, and dated the 5th April 1876.
PROVISIONAL SPECIFICATION left by the said John Richardson Wigham at
the Office of the Commissioners of Patents on the 5th April 1876.
JOHN RICHARDSON WIGHAM, residing at Capel Street, in the City of Dublin,
Ireland, Gas Engineer. "IMPROVEMENTS IN AUDIBLE FOG AND OTHER SIGNALS."
My Invention relates to audible signals produced by an instrument of the kind
known as a siren, wherein a disc with holes or slots in it being made to revolve
rapidly by steam, compressed air, or other fluid under pressure in front of another
perforated or slotted disc, a loud note is produced by the intermittent passage of
the fluid through the slots or perforations.
The chief object of my Invention is the arrangement of an instrument of this
kind in a compact and convenient form, such as may be used for signalling purposes
on shipboard or at lighthouses or signal stations, the apparatus being so arranged
that the sound can be directed to any desired quarter, and can be varied and
interrupted at regular intervals. For this purpose I provide a pipe with a valve
through which the steam or acting fluid passes in greater or less volume according
as the valve is more or less opened, and for the purpose of varying the valve
opening a rotating valve may be employed worked by gearing from a hand wheel
mounted on the pipe which may also serve as a stand for the apparatus. On the
pipe I provide a stuffing box receiving a trunnion projecting from the side of a
cylinder. One end of this cylinder constitutes the fixed, slotted, or perforated disc,
and on its outer face is mounted the rotating disc. The holes or slots in these
dises may have their edges inclined, so that fluid issuing through them causes the
loose disc to revolve. I prefer however to drive the rotating disc by making a
current of the steam or acting fluid play on straight or inclined or curved fans or
vanes, or on a turbine wheel fixed on the axis of the disc. The cylinder and its
discs are all enclosed in a trumpet-mouthed casing which along with them can be
turned round in any direction on the trunnion joint. The sound produced by the
siren can thus be directed to any quarter by turning the mouth of the trumpet in
the desired direction, and the note can be varied in pitch and volume or entirely
ID Ca

page_text: interrupted by varying or closing the valve passage for the acting fluid to the
rotating disc or to the fans or vanes, or to the turbine wheel which drives it.
Instead of employing fixed and rotating discs as above described for producing
the sound two cylinders may be used in the same apparatus, the one cylinder
fitting within the other with slots or holes on their peripheries, so that when either
is caused to rotate the steam or acting fluid in passing through the slots or holes
produces the sound as in the case of discs.
If it be desired that the siren should be sounded at stated intervals, the valve for
the admission of steam or other actuating fluid may be opened and closed at the
desired intervals by means of clockwork.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Richardson Wigham in the Great Seal Patent Office on the
3rd October 1870.
JOHN RICHARDSON WIGHAM, residing at Capel Street, in the City of Dublin,
Ireland, Gas Engineer. "IMPROVEMENTS IN AUDIBLE FOG AND OTHER SIGNALS."
My Invention relates to audible signals produced by an instrument of the kind
known as a "siren," wherein a disc with holes or slots in it being made to revolve
rapidly by steam, compressed air, or other fluid under pressure in front of another
perforated or slotted disc, a loud note is produced by the intermittent passage of the
fluids through the slots or perforations.
The chief object of my Invention is the arrangement of an instrument of this
kind in a compact and convenient form, such as may be used for signalling purposes
on shipboard or at lighthouses or signal stations, the apparatus being so arranged
that the sound can be directed to any desired quarter, and can be varied in note
sounding two or more notes in succession, or interrupted at regular intervals. For
this purpose I provide a pipe with a valve through which the steam or acting fluid
passes in greater or less volume, according as the valve is more or less opened, and
for the purpose of varying the valve opening a rotating valve may be employed
worked by gearing from a hand wheel mounted on the pipe which may also serve
as a stand for the apparatus. On the pipe I provide a stuffing box receiving a
trunnion projecting from the side of a cylinder or chamber of any shape. One end
of this cylinder constitutes the first slotted or perforated disc or discs, and on its
outer face is mounted the rotating disc or discs. The holes or slots in these discs
may have their edges inclined, so that the fluid issuing through them causes the loose
discs to revolve or assists in driving them. I prefer however to drive the rotating
disc or discs by making a current of the steam or acting fluid play on straight or
inclined or curved fans or vanes, or on a turbine wheel fixed on the axis of the disc
or geared or connected with the same. The cylinder and its dises are all enclosed
in a trumpet-mouthed casing, which along with them can be turned round in any
direction on the trunnion joint. The sound produced by the siren can thus be
directed to any quarter by turning the mouth of the trumpet in the desired
direction, and the note can be varied in pitch and volume or entirely interrupted
by varying or closing the valve passage for the acting fluid, or successively turning
it on to the rotating discs or to the fans or vanes, or to the turbine wheel which
drives it so as to produce either steady sounds of one note or sounds of varying
pitch, or of more than one note.
Instead of employing fixed and rotating discs as above described for producing
the sound two or more cylinders may be used in the same apparatus, the one
cylinder fitting within the other with slots or holes on their peripheries, so that
when either is caused to rotate the steam or acting fluid in passing through the
slots or holes produces the sound as in the case of discs.
When it is desired to sound two blasts of different note consecutively the
annular or cylinder discs as above described may be placed side by side with their

page_text: trumpet mouths in the same plane, or back to back, or at any desired angle from
each other, and the sounding apparatus may work each separately or be so arranged
ns to work both sirens according as convenience may dictate.
If it be desired that the siren should be sounded at stated intervals, the valve.
for the admission of steam or other actuating fluid may be opened and closed at the
desired intervals by means of clockwork or by any other motive power.
The accompanying Drawing shews a side view of my before described improved
signal apparatus. A is a fixed steam pipe having a stuffing box B through which
passes a hollow trunnion C, connected to and conveying the steam into the casing D.
of the sounding apparatus, which consists of fixed and rotating slotted discs as
before described. To the casing is attached the trumpet E which can be turned so
as to propel the sound in any direction by turning the casing D on its trunnion.
A pipe F conveys a jet of steam against a turbine wheel G, the rotary motion of
which is communicated through gearing to the spindle H of the rotating disc of the
sounding apparatus. In the steam pipe A is a rotary valve I actuated by gearing
from the crank handle K, so that by turning the valve into a more or less open
position, the sound of the siren may be varied in tone. The trunnion C may have
a branch for supporting and conveying the steam or other operating fluid to a
second similar sounding apparatus arranged by the side of the other one for the
purpose of sounding another note. For this purpose also a single siren disc may be
employed having two or more rings of slots or perforations so arranged that the
operating fluid can be admitted to act on any of the rings, suitable valves being
provided for directing it as desired.
Having thus described the nature of my Invention and in what manner the same
is to be performed, I claim, the construction of audible signalling apparatus wherein
a siren in its case is mounted with a hollow vertical trunnion in a stuffing box on
the pipe conveying the steam or other operating fluid, the rotation of the disc of the
siren being effected by a turbine or vane wheel acted upon by a jet of steam or
other fluid from the said pipe, substantially as herein described.
In witness whereof, I, the said John Richardson Wigham, have hereunto set
my hand and seal, this Second day of October, in the year of our Lord One
thousand eight hundred and seventy-six.
JOHN RICHARDSON WIGHAM. (L.S.)