Improved Apparatus for Indicating Changes of Temperature.
Year: 1898

page_text: Date of Application, 6th Jan., 1898
Complete Specification Left, 6th Oct., 1898-Accepted, 19th Nov., 1898
Improved Apparatus for Indicating Changes of Temperature.
I, JOSEPH THEODOR SZÉK, of 63 and 64, Chancery Lane, in the County of London,
Manufacturer (a communication from Adolf Lyncker, Lieutenant [Retired List], of 26,
Schwindstrasse, Munich, in the German Empire), do hereby declare the nature of
this invention to be as follows:-
This invention relates to improvements in apparatus for indicating when the
temperature rises or falls beyond a certain limit in store rooms, green houses,
factories and other places.
According to this invention a tube is provided one part of which is made of thin
copper, brass, or the like, the other part of glass or similar material. The whole
tube is U shaped and suitably mounted on a board. It is preferable to make one
"leg" of the U longer than the other.
The shorter leg of this U tube, the bend, and a portion of the longer leg are
formed by the glass-part the remainder is the metal tube closed at the top and
hermetically sealed to the glass part.
The bend of the U tube and a portion of each leg are filled with mercury so as to
confine a column of air in the long leg of the U, the contraction or expansion of the
air column determining the level of the mercury in the short leg of the U which
communicates with the atmosphere.
If the apparatus is only to indicate an undue rise in temperature two insulated
wires are led into the open leg of the U tube their ends being bare. These ends are
at the same level and may be raised or lowered by means of a set screw, or they may
be held by a simple plug loosely fitting the mouth of the U tube. When the
temperature rises, the copper-portion rapidly communicates heat to the air within,
the air-column expands, forces the mercury down in the long leg of the U tube causing
a corresponding rise in the other, so that the mercury reaching the two wires closes
an electric circuit which rings a bell or is otherwise made to indicate the fact.
If the apparatus is to indicate predetermined points in both falling and rising
temperature one wire is led to the bottom of the U so as to be permanently covered
by mercury, another is adjustably mounted in the long part and a third adjustable
in the short part of the U. When the predetermined maximum or minimum is reached
the circuit is closed on the corresponding side and the signal made.
The apparatus may also be arranged to indicate minimum temperature only.
In order to increase its sensitiveness the short leg of the U tube may be of less
diameter than the long leg.

page_text: Improved Apparatus 10
1, JOSEPH THEODOR SZÉK, of 63 and 64, Chancery Lane, in the County of London
(a communication from Gustav Adolf Lyncker), 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 apparatus for indicating when the
temperature rises or falls beyond a certain limit in store rooms, green houses, factories,
and other places.
According to this invention a tube is provided one part of which is made of thin
copper, brass, or the like, the other part of glass or similar material.
The whole tube is U shaped and suitably mounted on a board. It is preferable to
make one "leg" of the U longer than the other.
The shorter leg of this U tube, the bend, and a portion of the longer leg, are
formed by the glass part, the remainder is the metal tube closed at the top and
hermetically sealed to the glass part.
The bend of the U tube and a portion of each leg are filled with mercury so as to
confine a column of air in the long leg of the U, the contraction or expansion of the
air column determining the level of the mercury in the short leg of the U, which
communicates with the atmosphere.
If the apparatus is only to indicate an undue rise in temperature two insulated
wires are led into the open leg of the U tube their ends being bare. These ends
are at the same level and may be raised or lowered by means of a set screw, or
When
they may be held by a simple plug loosely fitting the mouth of the U tube.
the temperature rises, the copper-portion rapidly communicates heat to the air
within, the air column expands, forces the mercury down in the long leg of the
U tube causing a corresponding rise in the other, so that the mercury reaching the
two wires closes an electric circuit which rings a bell or is otherwise made to indicate
the fact.
If the apparatus is to indicate predetermined points in both rising and falling
temperature one wire is led to the bottom of the U so as to be permanently covered
third
by mercury, another is adjustably mounted in the long part and a
adjustably in the short part of the U. When the predetermined maximum or
minimum is reached the circuit is closed on the corresponding side, and the signal
made.
The apparatus may also be arranged to indicate minimum temperature only.
In order to increase its sensitiveness the short leg of the U tube may be of less
diameter than the long leg.
modification of
the
In the accompanying drawings two forms of the apparatus are shewn, Fig. 1
being a front view of one form, and Fig. 2 of
apparatus.
In either case A is the glass-portion, B the part made of metal, (copper, brass,
or the like). The apparatus shewn in Fig. 1 is mounted on a base board C, that
shewn in Fig. 2 has no base board the parts being carried by a block C¹ of hard
india-rubber or other suitable material.
In either case the lower part of the glass tubing contains mercury to a suitable
level a, and the apparatus is fitted in any suitable manner with electrical
connections.
Thus in Fig. 1, D is a plug of insulating material through which passes a rod D¹
terminating in a wire b. As will be seen in the sectional plan Fig. 1 (much
enlarged) the plug is grooved for the passage of the second wire b¹. A bridge b²
carries the rod D₁, and the nuts 63, 6³ serve for adjusting and retaining in place the

page_text: plug D and hence the wire b. The wire b¹ is stationary. The wire b is connected
with the terminal c, wire b' with the terminal c¹. If preferred both the wires may
be carried up and down with the plug D.
If the apparatus is set as shewn in Fig. 1, then, when the ambient temperature
rises, the column of air confined above the mercury in the part B will expand and
drive the mercury up in the part A, this will cause the ends of both wires to dip in
the mercury and establish electrical connection between the wires thereby causing the
the bell or other apparatus within the circuit to act.
It will be readily understood that the apparatus may be variously modified, thus
the plug D may carry both wires up or down as required.
In the form illustrated in Fig. 2 the tube B is connected with one terminal and
a thin tongue of metal within it, shewn in dotted lines, extends down into the
mercury.
This form does not differ substantially from that previously described and the
apparatus will be readily understood from the fore-going, as well as adaptations of
this invention for varying circumstances.
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 :-
An improved apparatus for indicating changes of temperature consisting in a bent
tube partly of metal, partly of glass, or the like, wherein a small quantity of mercury
confines a column of air so that the expansion or contraction of the air column
produces alterations in the level of the mercury completing or breaking an electrical
circuit substantially as set forth and illustrated in the drawings.
atation 1000
BERNHARD DUKES,
226, High Holborn, London, W.C., Agent for the Applicant.