Improvements in Heat Indicating Apparatus.
Year: 1894

page_text: Date of Application, 27th June, 1894
Complete Specification Left, 20th Mar., 18-5-Accepted, 27th Apr., 1895
PROVISIONAL SPECIFICATION.
Improvements in Heat Indicating Apparatus.
I FREDERICK WILLIAM GOLBY of 36 Chancery Lane, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention as
communicated to me by Franz Harde, Goldworker, and Johann Gerhard Hams,
Watchmaker, both of Rhede, Germany, to be as follows:-
Various apparatus of somewhat complicated nature mostly actuated by the
expansion of a column of mercury have hitherto been in use for indicating by
means of an alarum or other audible signal in an electric circuit, the degree of
friction or "running hot" of various parts of machinery, (such for instance as axles
and the like), and also for indicating an unusual or dangerous degree of heat in
rooms or other places. Such apparatus are not only costly and fragile, but they
can only be attached with very great difficulty, if at all, to machinery and ware-
houses. Apparatus other than these, and of a cheaper description, have to be taken
to pieces after each alarum or signal, otherwise they will not be able to give a
second alarum or signal.
The present invention relates to a simple cheap and durable heat indicating
apparatus, which can be reset in a few seconds after each alarum.
The apparatus consists of a metal case closed at each end with discs of material
which will not easily conduct heat or electricity. Through one of the discs passes
the end of a metal spring which is connected with the positive pole of an electric
battery, the free end of the said spring being bent over into a hook like shape.
This spring carries a small plate which is made of a non-conductive material and is
attached to the wall of the case by means of a substance fusible at a given
temperature, the attachment being such that the plate retains and gives tension to
the spring. Opposite the bent end of this spring and connected to the interior of
the case is a metal bridge; the bent-end of the spring strikes this bridge as soon
as the material retaining the plate is melted by the rise in temperature of the case
to which it is attached. The wall of the case is connected with the negative pole
of the battery, so that the electric circuit is closed when the bent end of the spring
is in contact with the bridge aforesaid. By this means an alarum in the circuit is
Bet going.
To enable the spring to be replaced in its former position, without having to take
the apparatus to pieces, a rod is attached to the plate, said rod projects through an
opening in the wall of the case, which opening is packed with insulating material.
By the aid of this rod the plate can be again pressed back onto the wall of the case
which must be heated for a short time at the spot where the glutinous substance is
placed, and then allowed to cool so that the substance may again bind the plate and
spring to the wall of the case.
The cases are constructed in accordance with the purposes for which they are
required, and have fittings etc., to enable them to be attached to parts of
machinery.
Dated this 27th day of June 1894.
F. W. GOLBY,
36, Chancery Lane, London, W.C.

page_text: COMPLETE SPECIFICATION.
Improvements in Heat Indicating Apparatus.
I FREDERICK WILLIAM GOLBY of 36 Chancery Lane, in the County of
Middlesex, Patent Agent, do hereby declare the nature of this invention as
communicated to me by Franz Harde, Goldworker, and Johann Gerhard Hams,
Watchmaker, both of Rhede, Germany, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
Various apparatus of somewhat complicated nature mostly actuated by the
expansion of a column of mercury, have hitherto been in use for indicating by.
means of an alarum or other audible signal in an electric circuit the degree of
friction or "running hot" of various parts of machinery (such for instance as axles
and the like) and also for indicating an unusual or dangerous degree of heat in
rooms or other places. Such apparatus are not only costly and fragile, but they
can only be attached with very great difficulty, if at all, to machinery and ware-
houses. Apparatus other than these, and of a cheaper description, have to be taken
to pieces after each alarum or signal otherwise they will not be able to give a
second alarum or signal.
The present invention relates to a simple, cheap and durable heat indicating
apparatus, which can be reset in a few seconds after each alarum.
In the accompanying drawings
Figures and 2 are sections at right angles to each other of the apparatus in the
set position and
Figure 3 is a section of the apparatus in the indicating position.
The apparatus consists of a metal case closed at each end with discs s and s¹ of
material which will not easily conduct heat or electricity. Through one of the
dises passes the end of a metal spring f which is connected with the positive pole
of an electric battery, the free end of the said spring being bent over into a hook-
like shape. This spring carries a small plate p which is made of a non-conducting
material and is attached to the wall of the case by means of a substance fusible at
a given temperature, the attachment being such that the plate retains and gives
tension to the spring f
Opposite the bent end of this spring fand connected to the interior of the case is
a metal bridge b; the bent end of the spring f strikes this bridge b as soon as the
material retaining the plate p melted by the rise in temperature of the case to
which it is attached.
The wall of the case is connected with the negative pole of the battery, so that
the electric circuit is closed when the bent end of the spring f is in contact with the
bridge baforesaid (see Figure 3). By this means an alarum in the circuit is set
going. To enable the spring to be replaced in its former position, without
having to take the apparatus to pieces, a rod t is attached to the plate p said rod t
projects through an opening o in the wall of the case, which opening o is packed
with insulating material. By the aid of this rod t the plate s can be again pressed
back on to the wall of the case which must be heated for a short time at the spot
where the glutinous substance is placed, and then allowed to cool so that the
substance may again bind the plate p and spring to the wall of the case.
The cases are constructed in accordance with the purposes for which they are
required and have fittings etc. to enable them to be attached to parts of
machinery.
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 :-
A heat indicating device consisting of a case contained in an electrical circuit

page_text: and having a spring f retained in the set position and in tension by a glutinous
substance fusible at high temperatures and a bridge b with which the spring f
makes electrical contact when the glutinous substance is fused, said spring being
furnished with or connected to a rod t by the aid of which the spring can from
outside again be pressed back on to the wall of the case and there secured in the
set position by reheating and allowing the glutinous substance to cool again
substantially as described and illustrated and for the purpose stated.
Dated this 20th day of Movch 1895
F. W. GOLBY,
36, Chancery Lane, London, W.C.