Improvements in Thermostatic Alarms.
Year: 1896

page_text: Date of Application, 4th Nov., 1896-Accepted, 5th Dec., 1896
COMPLETE SPECIFICATION.
Improvements in Thermostatic Alarms.
We, PERCY CARLETON HOWE, Mechanical Engineer, of 17 Upton Street, and
HENRY JAMES HOWES, Master Mariner, of 107 East River Street, Hyde Park,
both of Boston in the State of Massachusetts, United States of America, 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:-
Our invention relates to automatic fire alarms, and has for its object to provide
a portable device of convenient size to sound an alarm so as to notify the occupant
of an apartment that the temperature thereof has risen to a degree that is
dangerous. Another object of the invention is to provide an alarm of the
character mentioned, which shall be structurally simple, and at the same time be
highly sensitive to thermal changes, and be so constructed as to work without fail,
in case of fire.
To these ends the invention consists of a fire alarm comprising in its construction,
a gong or sounder, spring actuated gearing or clockwork, a striker for the gong
actuated thereby, and a thermostat arranged to check the action of the clock work,
except when the temperature of the apartment has risen to a degree sufficiently
high to cause the thermostat to move and release the clockwork so as to allow the
latter to actuate the striker. It likewise consists of a mechanically actuated alarm
provided with a gong, and a casing arranged to form a chamber within which the
operative parts are mounted, and the whole is so constructed and arranged as to
be carried in the pocket or in any other convenient place. Our invention also
consists of a suitable alarm of the character described, provided with other
improvements of greater or less importance, as we shall now proceed to describe
with particularity and set forth in the appended claims.
Reference is to be had to the annexed drawings and to the letters and figures
marked thereon, forming a part of this specification, the same letters designating
the same parts or features, as the case may be, wherever they occur.
Of the drawings-
Figure 1 is a central vertical section through our fire alarm so as to show the
internal construction of the same.
Fig. 2 is a plan view of the same with the casing removed..
Fig. 3 is a plan view of the alarm, reversed so as to have its bottom upper-
most, the gong being removed.
In carrying out our invention, we employ a base plate a, which is provided with
apertures whereby it may, if desired, be screwed or otherwise fastened to a wall.
or to any other suitable place.
c is a vertical standard which supports the operative parts of the device, it being
threaded at its lower end so as to be maintained in position upon the base plate,.
which has a centrally threaded aperture to receive it.
dd are substantially triangular plates through which the standard passes, they
being secured together by the bars ee. Between these plates, we mount a clock-
work, consisting in this case of a spring f having one end secured to the standard.
(which also acts as a main arbor) and its lower end fastened to one of the bars e
a main gear wheel g rigidly secured to the standard or arbor, a pin wheel h actuated
thereby, and an escapement wheel i on the arbor of the pin wheel.
These

page_text: constitute what we have chosen to term clockwork" or "spring actuated
gearing," and they may be varied: assoccasions requires. j indicates an escapernent
to which a striker k is secured, so that when the wheel i is rotated, the striker is
actuated, as will be clearly understood.
is a ring which is secured to the plates d and upon the inwardly extending
flange m of which is mounted a bridge which is ring shaped at n, with downwardly
extending supports o secured by rivets or bolts in the ring.l.
Upon the bridge or ring n we secure a thermostat p which consists of a tank,
circular in plan view with a thin. metallic flat bottom, and a thicker metallic top
which is segmental in section. The edges of the top and bottom plates are secured
together and the tank thus formed is filled with some chemical or liquid which is
highly sensitive to thermal changes. The top plate being relatively thick, the bottom
plate is forced downward when the contents of the tank expand. The tank is
detachably held in place on the ring by set screws p', the head's of which are
arranged to impinge upon its edges.
The thermostat is employed to release the clockwork when a predetermined
temperature is reached through the following devices.
9 is a bar pivoted at its end to a stud r on the supporting ring l: and having its
other end connected with a check or stops which is held by a spring t, when in
normal position, to impinge against the striker and prevent it and the clockwork
from moving. When the bar'q is depressed, however, the check on stop s is moved
out of the path of the striker, so that it may be actuated:
The bar q is provided with an upright pin or stud. u upon which a cap vis
adjustably mounted. When the bottom plate of the thermostat is forced down-
ward by the expansion of the contents of the latter, the bar g; through the
medium of the cap and pin u; is depressed and the stop is moved out of engage-
ment with the striker. The cap may be adjusted, so as to be: engaged by the
thermostat at any certain temperature, but for ordinary purposes, we find it
désirable to arrange the parts so that the bar will be depressed when the
temperature is at about 105° Fahrenheit.
The parts above described are confined within and protected by an inverted
concavo-convex gong w which is screwed on the standard c, and as concavo-convex
perforated casing, which is supported upon the ring 1. The casing and the
gong are equal in diameter so that their edges coincide and form a chamber, the
said edges being slightly separated so as not to interfere with the vibratory
qualities of the bell or gong.
From the foregoing it will be seen that we provide an automatic fire alarm which
is simple in structure, with but few parts, and which may be carried on the
person. The operative parts are all contained within a chamber, the walls of
which afford ample protection to them.
The actuating spring for the gearing is connected as said, with the standard, so
that when it is desired to wind it, the casing is grasped with one hand, and the
base plate with the other, and the two parts are rotated relatively to each other.
And when the check or stop is moved out of engagement with the striker, and the
striker is being actuated, the casing will revolve around the standard. Thus it
will appear obvious that we provide a simple means for winding the spring.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to. be performed,, we declare that what we
claim is:
1. As a new article of manufacture, a portable fire alarm comprising in its
construction, a gong, a standard, and a concavo-convex casing all secured together,
whereby the gong and casing form a closed chamber, said gong and said casing
being rotatable relatively to each other, in combination with a striker, clockwork
for actuating said striker a detent normally locking the striker against movement
and a thermostat connected with said detent for moving it to release the striker
when a predetermined temperature is reached.

page_text: 2. A portable fire alarm comprising a supporting ring, clockwork supported on
said ring, a standard rotatably connected with the said ring, a casing secured to
the ring, and an inverted gong secured to the standard, forming with the casing an
enclosed chamber, in combination with a striker in said chamber and operated by
the clockwork, and a thermostat, supported on the ring, for releasing the striker
when a predetermined temperature is reached.
3. A portable fire alarm comprising in its construction, a base, a standard, a gong,
a supporting ring connected to said standard, and a perforated casing, in combination
with a striker supported by the ring, clockwork for rotating the striker, a spring
held rod pivoted in the ring and normally engaging the striker to hold it against
movement, a bridge mounted on the ring, and a thermostat secured to the said
bridge and in operative relation to said rod, to move it and release the striker when
a predetermined temperature is reached.
4. A portable fire alarm comprising a striker, clockwork for actuating the
striker, a pivoted detent for the striker, a thermostat for actuating said detent
at a given temperature a supporting ring on which the said parts are all supported,
a casing mounted on said ring, and an inverted gong connected to said ring, and
forming with said casing a chamber in which all the foregoing parts are completely
confined.
Dind:01
Ootcha 1900
PERCY CARLETON HOWE.
HENRY JAMES HOWES.
Haseltine, Lake & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicants.