Improvements in Low-water Alarms for Steam Boilers.
Year: 1892

page_text: Date of Application, 9th Mar., 1892-Accepted, 23rd Apr., 1892
Improvements in Low-water Alarms for Steam Boilers.
1, JAMES TAYLOR Kimberworth Road, Masbro' in the County of York,
Engineer, 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 improvements in the construction of low water alarms
which are applicable to Cornish, Lancashire, upright and other boilers, the object
being to improve the general construction, to permit the ordinary movement of the
float without sounding the alarm, and to provide ready means for testing the
efficiency of the apparatus.
1 have illustrated the method in which the invention can be successfully carried
into practice, on the annexed sheets of drawings in which like letters of reference
indicate like parts in any of the figures.
Fig. 1, is a side elevation of the apparatus as fixed in a horizontal boiler.
Fig. 2, is a plan of same.
Fig. 3, is an enlarged front clevation of the valve and adjacent parts.
Fig. 4, side view of same.
Fig. 5, plan of Fig. 3.
Brietly this invention consists of a float balanced upon a rocking lever, carried
by a suitable framework secured to the inside of boiler, a steam valve and alarm
capable of being operated by the rocking lever, and a test rod conveniently situated
for the attendant to test the efficiency of the alarm at any moment.
In carrying out my invention as shown in the drawings, A, represents the shell
of a boiler, A2 being the front plate, to the inside of which I attach a bracket B,
which can be made by bending a wrought iron bar to the form required to suit
the kind of boiler, and this is bolted to the front plate A2, as shown.
To the lower part of the bracket, I secure a double arin C, preferably of cast
iron, extending forward, and forming the support and fulcrum for the float lever D,
which carries the float F, with its rod E, and at the other end the balance
weight W, and any adjusting weights W2, that may be necessary; these weights
are half circles and are held by a pin W³, entering the hole W.
D and D, are lugs on the float lever, the upper one is for the top part of testing
lever L, to engage with when testing, the lower one D³, is to enable the lever to be
reversed when the top lug is worn.
G, is the testing rod, usually made of brass; it is attached loosely to the end of
the wrought iron testing lever L, passing through the front of boiler, and through
a stuffing box H, on the outside, and provided with a handle I, by which it can be
readily pulled out at any time, for testing or otherwise; when at rest it does not
interfere with the action of the float.
Upon the bracket B, over the back end of the float lever D, I fix a steam
valve V, preferably enclosed in a casing K, to keep it clean; this valve is to
permit steam to pass to the alarm J, (usually a steam whistle) its construction is
shown more clearly in Figs. 3, 4, 5.
The valve proper V, consists of a pin having a conical end, which fits into a
coned seating, and is held in the enlarged part of the slide M, by means of its
collar V2, and a cover plate V³.
The valve can be turned round, and bedded or ground on to the seating, by
means of its projecting end V, without removing it from its position.
It is carried by the vertically moving frame M, which is raised by the end of
the float lever D, when the float sinks low enough, or when the lever D, is acted
upon by pulling out the test rod G.

page_text: This movable frame M, can slide vertically on the adjustable guide pin R, valve
pin V, and the tee piece N, which is screwed upon a short fixed pipe P, com-
municating with the whistle.
When the valve is raised, steam will pass through the openings Q, through the
valve seating and pipe P,to the whistle. Normally, the valve is closed.
When the testing rod is pushed in as shown the upper part of the lever L, which
rocks on the same fulcrum or axis as the lever D, is at such a distance from the
lug D, as not to interfere with the ordinary action of the float; when the water
level is too low the back end of lever D, comes in contact with the end of pin R,
raises the valve and causes the alarm to sound.
When the test rod G, is drawn out the end of lever L, presses against the lug 'D²,
and depresses the float, raising the opposite end of lever and opening the valve as
before described.
The weight is prevented from rising too high by coming in contact with the
underside of the arm C, and from descending too low by the metal stop .S, inside
cast iron bracket C.
Although I have mentioned.certain materials as used in the construction of some
of the parts, such as the float brackets and the like, do not bind myself to any
particular material.
It will be understood that in some forms of boilers the wrought iron bracket_B,
will have to be varied in form as in some cases it may be necessary to suspend it
from its upper end, in others it may have to be bolted to the underside of
the top of boiler, and the whistle or other alarm may be fixed on the top of
boiler, and some of the other details may require to be varied, as will be well
sunderstood by engineers.
.
In case that the hoppers of mechanical stokers are in the way of such tan
arrangement as that shown, by leaving off the lugs from lever D, the test-rod
may be carried through, the top of the boiler if desired, in this case it is better to
curve the lower arm of the lever L.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I may say that I am
aware that low water alarms are made with floats, levers, whistles, and test rods,
and therefore I do not claim such, broadly but I declare that what I claim is :-
1-An improved low-water alarm, consisting of a bracket B, carrying a double
arm C, which supports the float lever :D, float F, and balance weight W, in com-
bination with a steam valve V, in communication with a steam whistle or alarm J,
also with a test rod G, and its lever L, arranged constructed and operating sub-
stantially as hereinbefore described and as shown in the drawings.
2 In low-water alarms, a steam valve V, carried by a vertically sliding
frame M, and communicating with the alarm constructed substantially as herein-
before described and as shown in Figs. 3, 4, 5, of the annexed drawings.
3-In low-water alarms for Cornish, Lancashire, or vertical furnace-boilers, a
double.arm C, having one or more lugs D2, and carrying the float lever D, float F,
and balance weight W, in combination with a test-rod G, and lever L, arranged
and constructed that when the test-rod is drawn out, the float will be depressed and
the alarm sounded substantially as hereinbefore described and shown.
Dated the 8th day of March 1892.
ROBT. F. DRURY, C.P.A.,
Bank Buildings, George Street, Sheffield, Agent for Applicant.