Improvements in Marine Fog Signalling Apparatus.
Year: 1895

page_text: Date of Application, 15th Oct., 1895-Accepted, 14th Dec., 1895
COMPLETE SPECIFICATION.
Improvements in Marine Fog Signalling Apparatus.
I, JOHN BLAKE TARR, a citizen of the United States of America, residing at
No. 18 South Emerson Street, in the Town of New Bedford, County of Bristol and
State of Massachusetts, one of the United States of America, Machinist, 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:-
This invention relates to an improvement in fog alarms, and the objects of the
improvement are to provide a simple and inexpensively operated machine for
light-houses and light-ships, to be used for signaling during fogs and snow storins,
when their lights are thereby obstructed. The air used in this machine being
compressed by steam power can be made to blow a whistle or a fog horn with such
force that they can be heard distinctly at a distance of ten or more miles. Another
object is to provide in the machine certain simple means to automatically and
accurately regulate the length of time occupied by the full blast of each machine
located in the same neighborhood, as said length of time must necessarily be
different, to permit mariners to locate thereby the location of their vessels.
I attain these objects by the construction illustrated in the accompanying
drawings, in which :-
Figure 1 is a front view of a complete machine constructed in accordance
with my invention, and inclles steam boiler to furnish the steam to the engine.
Figure 2 is a vertical central section through the air blower cylinder, its
valves and piston, and showing its supporting frame and a portion of its operating
mechanism.
Figure 3 is a top view of the supporting frame of the blower cylinder with
the latter removed, but showing the operating and controling mechanism of
the device.
Figure is an end view of the device showing its operating and controling
mechanism with the blower cylinder removed.
Figure 5 is a side view of the whistle carrying pipe and the adjustable sound
deflector for said whistle.
Figure 6 is a side view of a fog horn which may be substituted for the whistle.
Figure 7 is a perspective view of the pipe used to lead air within the top of the
blower cylinder to permit the descent of the piston within the said cylinder, the
speed of said descent being controlled by the size of the passage within the pipe,
said passage being regulated by a cock at the lower end of said pipe, the plug of
said cock carrying an index finger which can be set opposite any one of the
divisions on an indicator plate secured above the cock.
Figure 8 is a perspective view of the frame carrying the clutch lever, and of
the trip vers used to automatically and also manually shift the clutch lever.
Figure 9 is a plan view of the piston of the blower cylinder.
Figure 10 is a perspective view of the circumferentially grooved clutch ring of
the machine.
Figure 11 is a top view of the supporting frame of the blower cylinder as shown
in Figure 3 but on a larger scale.
Figure 12 is a vertical section of the lower portion of the blower cylinder and
its piston, with a portion of the cylinder supporting frame, and the piston in the
act of bearing upon the upper tripping lever.
In said drawings A represents a steam boiler, preferably of the form known as
vertical tubular, from which steam is conducted through the pipe a³ to the steam

page_text: chest of the engine by means of a pipe a' branching laterally from the bottom of
the pipe a. Upon the pipe a' there is a valve that can be closed by the
operator when desired, and upon the pipe a³ there is a cock a that is automatically
closed by the clutch lover d'of the machine as soon as the pistone of the blower-
cylinder Erenches the upper end of its course, and is again automatically opened
by the inverse motion of the clutch lever d as soon as the piston e reaches the
lower end of its course. For this purpose the outer end of the clutch lever,
Figure 3, is connected by means of a linke with a crank arm secured to the upper
end of a vertical shaft pivotally retained in bearings e secured to the frame C
that supports the lower cylinder and other parts of the machine. The lower
portion of the shaft carries also a crank arin that is united by means of a
connecting rod with the handle af of the cock u'.
As the steam cylinder B of the engine that forces upward the pistone of the
blower cylinder is comparatively small to reduce the amount of steam used, said
engine is intended to be run at a high rate of speel, probably one thousand
revolutions of the crank shaft per minute, and it is desirable that the engine
should respond instantly to the starting motion of the operator without danger of
finding the engine on a dead centre, the engine is intended to be kept under very
slow motion. For this purpose a short steam pipe a passing on the side of the
cock a' has its ends connected with the steam pipe in front and rear of said cork,
and the capacity of said pipe af is controlled by a cock a. Said pipe a may have
one end attached directly to the boiler if desired. The exhaust steam from the
cylinder Bescapes through the pipe that is extended upwards any desirul
distance.
The steam power exerted upon the piston and piston rol B* of the cylinder Bis
transmitted by means of the connecting rod to the crank B on the shaft
Said shaft is mounted in suitable hearings on the frame and carries an eccentric,
eccentric-strap, and rod F, through which an ascillatory motion is given to a short
shaft pivotally retained in a wide bearing cured to the frame C. Said shart
carries at one end a crank pivoted at its outer end to the eccentric rod, and at
the other end a crank having its outer end pivoted to the adjustable slide-valve
rod'.
"
The shaft carries also a fly wheel F, and on its unter end a pinion F³ that
meshes with a gear wheel G on one end of a shaft carried in suitable bearings
upon the frame C on a higher level than the shaft. Said gear wheel Gerries
on its outer face a drum around which a rope can be wound and be used for
hoisting coal or other substances, with the engine of the apparatus, into ligh
houses or light ships in which it may have been forated. Upon the shuft " there
also loosely mounted, about midway of its bearings a pinion (³ that is made to mesh
with the rack piston red E' of the pistone of the blower cylinder. One of the
faces of the pinion G³ Lears against a callar g² secured upon the shaft but the
opposite face of the pinion is provided with a short collar having a groove g³ leng.
wise thereof to be used as one member of a clutch. The second member consists
of a feather that is carried by a circumferentially grooved sleeve that is received
within a ring formed on the inner end of the clutch lever d. Said sleeve and
feather are retained pivotally connected as usual with the ring of the clutch lever
by means of two pins or short screws inserted into the periphery of said ring and
having their inner ends received into the circumferential groove of sleeve or
leather a. The outer end of said feather is made to slidingly fit within a groove
formed lengthwise of a collar. The groove in the collar of the pinion is of
greater width than the width of the feather d to insure the entrance of said
feather within said groove, and to permit the shaft g to have a full head of
motion before it begins to rotate the pinion as the latter is loaded by the pump
piston.
The clutch lever is passed through a horizontal slot in a horizontal bar C that
forms a part of the frame and unites together the upper portion of its uprights C.
The bar C has formed on one of its sides a narrow shelf to which the lever dis

page_text: pivoted at d. When the piston e is ascending, the feather of the clutch lever is
normally retained in engagement with the pinion G³ by means of a spring pressing
ngainst the inner side of said clutch lever on the end thereof opposite the feather
carrying ring.
To automatically unclutch the pinion G³ when the piston e has reached the upper
end of its predetermined course, the piston rod E" carries adjustably thereon a
rectangular sleeve E³ that is secured thereto by a screw ³, the point of which is
made to enter either one of the holes in the side of the piston rod. As shown in
the drawings, said sleeve is secured to the lower end of the piston rod to permit the
latter to make a full stroke, before the pinion G³ is unclutched from its shaft. To
automatically unclutch said pinion when the piston e has reached the upper end of
its course, the sleeve E³ upon its rack rod E has a lateral projection es that comes
into engagement with the end of the lower arm of an angular lever that is
pivoted at to tlie side of the horizontal bar C3 of the frame. The upper arm of
the angular lever h has pivoted to its side at , Figure 8, one end of a link that
has its opposite end pivoted to the ring-end of the clutch lever and thus pulls said
ring end sidewise, and with it the clutch finger, and thus leaves the pinion free to
rotate on its shaft under the impulse of the descending rack-rod and piston, the
weight of said rack-rod being sufficient for that purpose, as the piston carries
suitable weights, as will be described.
During the descent of the piston the lower arm of the angular lever is retained
in a nearly horizontal position by having the point of its upper arm come into
engagement with the inner end of a trip lever i that is pivoted at to the side of
the horizontal bar C. The outer end of the trip lever is kept normally in a partly
elevated position by a flat spring & pressing it, the inner end of said spring being
secured at 2 on top of the bar C². A pin projecting from the side of the inner
end of the trip lever i rests on top of the secured end of the spring k and prevents
said inner end of the trip lever from being depressed too much by the upward
pressure of the spring k.
When the piston e reaches nearly the lower end of its course, it presses upon
the outer end of the trip lever i, and the inner end of said lever becomes tilted
upwards, and releases the angular lever h, the upper arm of the latter becoming
t.lted under said inner end of the lever i, the lower arm of the angular lever h
assuming then the position shown in dotted lines in Figure 8, said P osition
sing maintained until the piston is again at the upper end of its course.
dotted lines position of the lever his caused by the spring d pressing against
the side of the clutch lever d, causing its ring end to be swung away from
the upper arm of the angular lever hand pulling on the latter by means of the
link.
Said
To permit the operator to produce with the machine, a series of short blasts
in quick succession, as for example, if a vessel is dangerously close to a light
ship, a light-house, or rocks in its neighborhood, a hand lever m is pivoted
at m to the side of the bar C3 of the frame, and has its outer end projecting
beyond the side of the frame to serve as a handle for said lever, while its
inner end is extended under a pin projecting from the side of the trip lever i
adjacent to its inner end, by which means said inner end of the trip lever can
be lifted out of engagement with the upper arm of the angular lever and
permit the ring end of the clutch lever d to swing laterally and its feather to
enter into engagement with the clutch member of the pinion G³ without
requiring the piston e to descend sufficiently to press on the outer end of the
trip lever i.
To permit the pinion G³ to remain loose upon its shaft g for any desired
length of time, when it is desired to use the steam engine of the apparatus for
hoisting coal or other objects, the operator takes advantage of the time that the
pinion G³ is loose upon its shaft while the piston and its rack-rod are descending,
and arrests its descent by clamping said rack-rod E. For this purpose a
lever nis pivoted at to a bracket secured to the side of the bar C2 of the

page_text: frame, the inner end of said lever is made to pass through a horizontal slot in
said bar C and press against the outer end of a sliding pin passing through
the side of one of the side bearings C³ of the rack-rod, said bearings being
integral with the bar C and projecting from one of its sides. The outer end
or handle of the lever is adjustably retained by means of a thumb-nnt mounted
upon a bolt a projecting from gaid handle and passing through a slot in the
outer erd of an arm having its inner end secured to the side of one of the
standards of the frame C.
The pistone of the blower cylinder consists preferably of two metal disks
between which two disks of leather are clamped, the upper disk of leather
having its edge turned up and the lower disk of leather having its edge turned
down. The turned up edge is wider than the thickness of the upper metal
disk, and the upper portion of said turned-up elge is kept in close contact with
the inner face of the cylinder by means of a suitable number of metal
segments that are loosely connected with the upper metal disk by means of a
screw passing through radial slots in the segments ². Each segment has n
standing lug against the inner face of which one end of a coil spring is made
to press, while the opposite end of said spring presses against a shoulder formed
upon a screw passing horizontally through a lage projecting from the upper
face of the upper metal disk of the piston. To give the necessary gravity to the
piston a series of weights are secured on top thereof.
On top of the blower cylinder E is mounted a valve ense P containing a valve p
adapted to he opened by having it lifted a short distance by the compressed air
in said cylinder. The valve case has on top thereof a pipe 1" that may be ten or
more feet high, to extend a suitable distance above the deck of a light ship. On
the upper end of said pipe is mounted a whistle P³ of suitable size. Above the
whistle there is placed a sound deflecting plate P" that is adjustably retained at any
desired angle by divergent braces having their upper ends hinged to the
ottom of said plate. The lower portions of the braces p² are secured to two
sleeves adjustably retained upon the pipe P while the lower portion of the
shorter brace is adjustably retained in a tubular brace by mens of a bolt or
screw passing through the side of said brace p. the lower end of which is also
secured to the sleeves p
In place of the whistle, a fog-horn Q may be substituted, in which case it is
desirable to have a pressure-regulating valve R, of any well-known construction,
mounted on top of the blower cylinder to prevent the reed in the bottom of the
horn from being injured by too great an air pressure.
To regulate and adjust the speed at which the piston a descends within the
blower-cylinder, and thereby regulate the amount of time between each blast of
the whistle or fog-horn, air is admitted above the piston through the top of the
cylinder E, by means of a pipe S that has on its lower end a cock, the plug of
which carries radially thereof an index finger that is standing in front of a
stationary index-plate preferably secured to the side of the blower cylinder.
The position of the index finger relatively to the marks on the face of the index
plate can be adjusted by partly rotating the plug of the cock by means of its
handle. The upper end of the pipe S enters a valve-case T secured on top of
the blower cylinder. Within said ease is placed a valve that has its sent on top
thereof in the walls of the valve cuse. so that it is open when it drops down in the
position shown in Figure 2 As soon as the piston e begins to ascend and
compress air above it, the valve fis fured upward by said air and closed against
its seat, even before the valve p controling the whistle is opened, as the valve is
of lighter weight than the valve p.
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 a fog alarm, the combination of a vertical bottomless blower cylinder, a
.

page_text: valve
piston therein, a sound producing device as described, mounted on the upper end
of a pipe standing upon said cylinder and connected with its interior, and
interposed between said sound producing device and the top of the bottomless
blower-cylinder, as described.
2. In a fog alarm, the combination of a vertical bottomless blower cylinder, a
piston therein, a sound producing device as described, mounted on a pipe connected
with the interior of said cylinder, a valve interposed between said sound producing
levice and the interior of the blower cylinder, and an air leading-in valve upon the
top of said bottomless cylinder substantially as described.
3. In a fog alarm, the combination of a vertical blower cylinder, a piston
therein adapted to descend by its own gravity, a sound producing device and a
valve thereunder mounted upon said cylinder, and an air leading-in valve also
upon said cylinder, with a pipe leading air to the latter valve and a cock upon
said pipe.
4. In a fog alarm, the combination of a vertical blower-cylinder, a piston
therein, a sound producing device and a valve thereunder mounted upon said
cylinder, and an air leading-in valve also upon said cylinder, with a pipe
leading air to the latter valve, a cock upon said pipe, the plug of which carries
an index finger, and an index-plate alongside of said finger, substantially as
described.
5. In a fog alarm, the combination of a vertical blower-cylinder, a sound
producing device and a valve thereunder mounted upon said cylinder, a piston
therein adapted to descend by its own gravity, its rack-rod, a sleeve adjustably
mounted upon said rod, and a clutch lever actuated by said rod and sleeve,
substantially as described.
6. In a fog alarm the combination of a vertical blower-cylinder, a sound
producing device and a valve thereunder mounted upon said cylinder, a piston
therein adapted to descend by its own gravity, a trip lever adapted to be tripped
by said piston, an angular lever released by sau tip leve, a clutch lever linked
to the angular lever and a spring pressing the clutch lever, substantially as
described.
7. In a fog alarm the combination of a vertical blower-cylinder, a sound
producing device and a valve thereunder mounted upon said cylinder, a piston
therein adapted to descend by its own gravity, its rack-rod, a pinion meshing with
the rack of said rod, said pinion being loose upon its carrying shaft and having a
clutch member on one of its sides, with a clutch lever carrying the second clutch
member, substantially as described.
8. In a fog alarm, the combination of a vertical blower-cylinder, a sound
producing device and a valve thereunder mounted upon said cylinder, a piston
therein adapted to descend by its own gravity, a trip lever adapted to be tripped
by said piston, and a hand lever m to trip said trip-lever and perimit a clutch lever
to be automatically swung laterally, substantially as described.
9. In a fog alarm, the combination of a vertical blower-cylinder, a sound
producing device and a valve thereunder mounted upon said cylinder, a piston
therein, a trip lever adapted to be tripped by said piston, the rack-rod of said
piston, a pinion and its clutch member, and a clutch lever, with a steam pipe, a
cock thereon and means connecting the plug of said cock with the clutch lever,
substantially as described.
10. In a fog alarm, the combination of a vertical blower-cylinder, a whistle,
its supporting pipe and valve thereunder mounted upon said cylinder, a sleeve
adjustably secured to said pipe, divergent braces secured to said sleeve, and a
sound deflecting plate pivoted to the upper end of said braces and adapted to
be tilted, substantially as described.
Dated this 15th day of October 1805
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents,