IMPROVEMENTS IN APPARATUS FOR AUTOMATICALLY INDICATING THE PRESENCE OF FIRE OR HEAT BY MEANS OF ELECTRICITY
Year: 1882

page_text: LETTERS PATENT to Edmund Edwards, of the firm of Edwards and Co:
Patent Agents and Engineers, of 40, Southampton Buildings, Chancery Lane,
in the County of Middlesex for an Invention of "IMPROVEMENTS IN
APPARATUS FOR AUTOMATICALLY INDICATING THE PRESENCE OF FIRE OR HEAT
BY MEANS OF ELECTRICITY "
A communication to him from abroad by
Barthelemy Carré, of Rouen, in the Republic of France
PROVISIONAL SPECIFICATION left by the said Edmund Edwards at the
Office of the Commissioners of Patents on the 15th July 1882.
EDMUND EDWARDS, of the firm of Edwards and Co: Patent Agents anıl
Engineers, of 40, Southampton Buildings, Chancery Lane, in the County of
Middlesex, "IMPROVEMENTS IN APPARATUS FOR AUTOMATICALLY INDICATING THE
PRESENCE OF FIRE OR HEAT BY MEANS OF ELECTRICITY "
[A communication
to him from abroad by Barthelemy Carré, of Rouen, in the Republic of France]
This invention has for its object improvements in the construction and arrange-
ment of apparatus by which automatic indications are given at any distance and at
any. desired places of the presence of fire or of heat above a certain temperature, in
houses, theatres, or other places.
The apparatus consists of an electrical wire circuit in which is included a
battery of any ordinary kind and one or more electric bells or other apparatus
by which the passage of a current of electricity is indicated in the ordinary way.
In a convenient position at or near the spot where the presence of fire or heat is to
be indicated is fixed firmly a foundation plate or board having a terminal con-
nection to which one end of the wire circuit is fixed, and a second terminal to
which the other end is fixed. In electrical connection with the first terminal is a
brass standard fixed to the foundation board to which is screwed one end of a
steel spring provided at its free end with a platinum point which is pressed by the
elasticity of the spring against a corresponding platinum contact piece upon a
[Price Bd. 1

page_text: second brass standard fixed to the foundation board and to which the second
terminal of the wire circuit is connected, and the electrical circuit being thus
complete the current from the battery passes freely and causes the bells or other
indicating apparatus in any parts of the circuit to operate,
At or about the middle of the length of the spring is fixed a hook enamelled or
coated with insulating material so as to prevent the possibility of the electric
current passing through it and through the thermometric wire either metallic or
non metallic which is connected to it in the manner hereinafter described. A stop
is fixed in a suitable position to prevent the spring from being accidentally drawn
too far back by the hook.
In order to hold back the spring sufficiently so as to prevent the platinum point
upon its extremity from touching the contact piece and thus setting in operation
the bells or other indicating apparatus, a wire or thread is stretched between
the hook upon the spring already described and a second hook at a sufficient
distance.
The stem of this second hook passes through guides upon a plate or board firmly
fixed in the required position, and it is made square so that it cannot turn round
in the guides, its outer end being screwed and provided with a nut or thumbscrew
by which the position of the hook can be adjusted so that the wire or thread is
stretched to the necessary extent, the elasticity of the spring keeping the nuț
always pressed against the guide.
The different parts of the apparatus may be covered and protected by wooden
or other cases.
The action of the apparatus is as follows:-The foundation boards carrying the
two parts of the apparatus as described are firmly fixed in the place where 'the
presence of fire or too great heat is to be indicated, and they are connected by
the wire or thread. If the distance between them is such that the wire or thread
cannot be stretched in a straight line, bell cranks or pullies may be used and in
this way it may be made to pass completely round a room, and may be concealed
under the cornices or in other convenient way.
The wire or thread may consist either of a metallic wire expan ling by heat and
contracting when the heat is reduced, and in this form the apparatus is more
particularly adapted for regulating the operation of heating apparatus by giving
indications when any maximum temperature is reached. Or, it may consist of a
thread either combustible or affected by an abnormally high temperature, such as
cotton and asbestos; and in this case the apparatus would indicate the presence of
fire, and is applicable, for instance, as a protection against accident from gas jets in
theatres or in any situation where the flame of a combustible gas is liable to
accidental increase, the thread being arranged so that it is not affected by the
ordinary flame but is burned in case of such accidental increase.
Whatever the material of the wire or thread may be, its length is adjusted by
the nut so that the platinum point only touches the contact piece when the
determined maximum temperature is reached, or when the thread is burned. It
will be seen, therefore, that the thread or wire may be of any length, in a straight
line or not, and that it may be composed of two or more separate parts metallic or
non-metallic; and directly its expansion or destruction permits contact between
the platinum point and contact piece, the bells or other indicating apparatus come
into operation.
In the novel apparatus described, the wire or thread affected by the heat does
'not form part of the electric circuit. It may be applied to numerous purposes, as
for instance, to give warning of fire or to prevent the increase of temperature above
a fixed maximum.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edmund Edwards in the Great Seal Patent Office on the
15th January 1883.
EDMUND EDWARDS, of the firm of Edwards and Co: Patent Agents and
Engineers, of 40, Southampton Buildings, Chancery Lane in the County of
Middlesex "IMPROVEMENTS IN APPARATUS FOR AUTOMATICALLY INDICATING THE
PRESENCE OF FIRE OR HEAT BY MEANS OF ELECTRICITY " A communication to
me from abroad by Barthelémy Carré, of Rouen in the Republic of France
· This invention has for its object improvements in the construction and arrange-
ment of apparatus by which automatic indications are given at any distance and
at any desired places of the presence of fire or of heat above a certain temperature
in houses, theatres, or other places.
The apparatus consists of an electric wire circuit in which is included a battery
of any ordinary kind and one or more electric bells or other apparatus by which
the passage of a current of electricity is indicated in the ordinary way. In a
convenient position at or near the spot where the presence of fire or heat is to be
indicated is fixed firmly a foundation plate or board having a terminal connection
to which one end of the wire circuit is fixed, and a second terminal to which the
other end is fixed. In electrical connection with the first terminal is a brass
standard fixed to the foundation board to which is screwed one end of a steel or
other metal spring provided at its free end with a platinum point which is pressed
by the elasticity of the spring against a corresponding platinum contact piece upon
a second brass standard fixed to the foundation board and to which the second
terminal of the wire circuit is connected, and the electrical circuit being thus
complete the current from the battery passes freely and causes the bells or other
indicating apparatus in any part of the circuit to operate.
At or about the middle of the length of the spring is fixed a hook enamelled or
coated with insulating material so as to prevent the possibility of the electric
current passing through it and through the thermometric wire either metallic or
nonmetallic which is connected to it in the manner hereinafter described. A stop
is fixed in a suitable position to prevent the spring from being accidentally drawn
too far back by the look.
In order to hold back the spring sufficiently so as to prevent the platinum point
upon its extremity from touching the contact piece and thus setting in operation
the bells or other inducting apparatus, a wire or thread is stretched between
the hook upon the spring already described and a second hook at a sufficient
distance.
The stem of this second hook passes through guides upon a plate or board firmly
fixed in the required position, and it is made square so that it cannot turn round
in the guides, its outer end being screwed and provided with a nut or thumbscrew
by which the position of the hook can be adjusted so that the wire or thread is
stretched to the necessary extent, the elasticity of the spring keeping the nut
always pressed against the guide. The different parts of the apparatus may be
covered and protected by wooden or other cases. The accompanying drawing is in
illustration of the invention. Figure 1 shews the electrical part of the apparatus,
and figure 2 the part by which the wire or thread is stretched. Figure 3 shews on
a smaller scale the principle on which the apparatus operates.
In figure 1, A, B, C, D, is the foundation plate or board, E is the stop. G is the
hook connected at M to the spring K, L, which is fixed to the standard J, and H, I
are terminals to which the wires are connected. N is the contact piece connected
to the terminal I by the wire O.

page_text: In figure 2 A¹, B, C, D', is the foundation plate or board, Q is the hook holding
the outer end of the wire or thread, its stem passing through the guides T, T', and
its outer end being screwed and fitted with a nut R.
In figure 3, A, B, represents a stretched wire or thread, C a spring the point D
of which can come in contact with the contact piece E. F is a battery, and G an
electrical bell or sounding apparatus.
The action of the apparatus is as follows:-The foundation boards A, B, C, D,
and A, B, C, D¹, carrying the two parts of the apparatus as described are firmly
fixed in the place where the presence of fire or too great heat is to be indicated, and
they are connected by the wire or thread A, B, (figure 3).
If the distance between them is such that the wire or thread cannot be stretched
it
in a straight line bell cranks or pullies may be used and in this way may
be
made to pass completely round a room, and may be concealed under the cornices
or in other convenient way. The wire or thread may consist either of a metallic
wire expanding by heat and contracting when the heat is reduced, and in this form
the apparatus is more particularly adapted for regulating the operation of beating
apparatus by giving indication when any determined maximum temperature is
reached.
Or, it may consist of a thread either combustible or affected by an abnormally
high temperature such as cotton and asbestos; and in this case the apparatus
would indicate the presence of fire, and is applicable for instance as a protection
against accident from gas jets in theatres or in any situation where the flame of a
combustible gas is liable to accidental increase, the thread being arranged so that
it is not affected by the ordinary flame but is burned in case of accidental increase.
Whatever the material of the wire or thread may be, its length is adjusted by the
nut R so that the platinum point L only touches the contact piece N when the
determined maximum temperature is reached, or when the thread is burned. It
will be seen, therefore, that the thread or wire may be of any length, in a straight
line or not and that it may be composed of two or more separate parts metallic or
non-metallic; and directly its expansion or destruction permits contact between the
platinum point and contact piece, the bells or other indicating apparatus shewn at G,
figure 3, come into operation.
In the novel apparatus described, the wire or thread affected by the heat does
not form part of the electric circuit. It may be applied to numerous purposes, as
for instance, to give warning of fire or to prevent the increase of temperature above
a fixed maximum.
Having now described the invention and the manner in which it is to be
performed, I claim :-The combination of the stretched wire or thread, the
adjustable hook and nut, the metallic spring and contact piece, the electrical
battery and conducting wires, and the bell or other sounding or indicating apparatus,
all arranged and operating substantially as and for the purposes described and
shewn in the drawing.
In witness whereof, I, the said Edmund Edwards, have hereunto set my hand
and seal this fifteenth day of January in the year of our Lord 1883.