IMPROVEMENTS IN FIRE WARNING AND INDICATING APPARATUS
Year: 1879

page_text: LETTERS PATENT to John Garrett Tongue, of the Firm of Tongue and Birkbeck,
Patent Agents and Engineers, 34, Southampton Buildings, Chancery Lane, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN FIRE
WARNING AND INDICATING APPARATUS." A communication from abroad by
Amédée Paulin Charpentier, of Paris, France.
PROVISIONAL SPECIFICATION left by the said John Garrett Tougue at the
Office of the Commissioners of Patents on the 6th September 1879.
JOHN GARRETT TONGUE, of the Firm of Tongue and Birkbeck, Patent Agents and
Engineers, of 34, Southampton Buildings, Chancery Lane, in the County of
Middlesex. "IMPROVEMENTS IN FIRE WARNING AND INDICATING APPARATUS."
communication from abroad by Amédée Paulin Charpentier, of Paris, France.
A
This Invention relates to new or improved fire warning and indicating apparatus.
This apparatus is based on the expansion of metal, or other bodies under the
influence of increased temperature, and consists of mechanism so arranged as to
register or indicate the expansion, and thus ascertain the temperature of the body
surrounding the apparatus which may be placed or fixed, for example, in a mass or
body gathered together, such as hay or other materials.
The apparatus based on the expansion of a solid substance is composed advan-
tageously of a rod of metal placed in a thin cylinder of glass or metal.
The rod is fixed at the lower part to a socket or boss at the bottom of the
cylinder.
The rod is surmounted with another smaller rod placed in such manner as to be
acted upon by the larger rod.
The rods are guided and kept in position by suitable guides.
The upper part of the smaller rod which is put in motion by the increase of
length caused by expansion of the lower rod is connected with a lever arm on a
toothed quadrant which transmits motion to a small pinion fixed to a spindle,
carrying a needle or pointer.
A graduated dial is fixed to the upper part of a small cylinder which surrounds

page_text: the smaller rod, so as to indicate the temperature corresponding to the different
degrees of expansion of the larger rod.
In order to regulate the apparatus the quadrant has only to be unscrewed.
The expansion of the atmosphere contained in the apparatus acts as an indicator
by means of a piston made steam tight, and fixed to the lower part of the operating
rod.
In order to indicate or register at a distance the warning given by the apparatus,
a stop on the electric contact system is fixed to the figure on the dial, showing the
temperature at which warning is to be given, and as it comes in contact with the
indicating needle puts in motion a bell or other apparatus for giving warning.
Any other suitable mechanical contrivance may be employed to serve the above
purpose.
The form and dimensions of the apparatus may be varied as well as the material
employed for the construction according to the purpose to which it may be applied.

page_text: The form and dimensions of the apparatus may be varied as well as the material
employed for the construction according to the purpose to which it may be applied.
Having thus described the nature of the Invention communicated to me from
abroad, and the manner of performing or carrying the same into practice; I do not
claim any of the parts,separately, which, are well known, but what I claim on
behalf of the said Amédée Paulin Charpentier is,
First. The improved fire warning, and indicating apparatus composed of a rod. of
metal placed in a cylinder or tube, fixed or placed in the centre of a mass of substances
in order to ascertain the degree of temperature, thereof, the changes in the length of
the said rod according to the temperature being indicated or registered by a quadrant
and dial by means of a convenient mechanical contrivance, substantially in the
imanner, and for the purpose described and shown in the Drawings hereto annexed.
Second. The improved fire warning and indicating apparatus composed of a tube
or cylinder containing air or other suitable fluid, and fixed or placed in the centre
of the mass of substances, the expansion of the atmosphere or fluid caused by the
change in temperature 'being indicated or registered by the action of a rod on a
quadrant and dial by means of a piston made steam tight; and fixed to the lower
part of the operating rod placed in a cylinder, substantially as and for the purpose
hereinbefore described.
Lastly. Shewing and registering at a distance by putting in motion a bell or
other apparatus by means of an indicating needle, fixed to the figure of the dial,
which comes in contact with a stop on the electric contact system, indicating the
maximum temperature, at which warning is to be given, substantially as and for
the purpose herein before described.
In witness whereof, I, the said John Garrett Tongue, have hereunto set my
hand and seal, this Fourth day of March, in the year of our Lord Ono
thousand eight hundred and eighty.