Improvements in Apparatus for Indicating or Signalling when Shaft Bearings and other Frictional Parts Run Hot.
Year: 1896

page_text: Date of Application, 7th May, 1896-Accepted, 15th Aug., 1896
COMPLETE SPECIFICATION.
Improvements in Apparatus for Indicating or Signalling when
Shaft Bearings and other Frictional Parts Run Hot.
I, ALFRED ALEKSANDER FRÜS of Kalajoki, Finland, Polytechnical Student
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 a device which by means of a convenient signal
indicates automatically when surfaces, being in frictional contact with each other,
for instance, in shaft bearings, slide valves, etc. begin to run hot. Such a device
is of great importance for instance in the steam engines in a steamer, in motors,
locomotives, bearings of railway wagons etc., where the running hot of a bearing or
the like may frequently cause great inconveniences.
This invention is founded upon the expanding influence of the heat upon the parts,
being in frictional contact with each other, the expansion being used for causing a
movement in the parts of a signal apparatus. The latter can be arranged in many
different ways. For instance some of the parts in frictional contact with each
other or some of the parts situated next to said parts may contain a closed cavity
filled with a liquid or fluid and connected with a pressure gauge or the like. The
hand of the latter turns when the said part begins to become hot in a noteworthy
degree, and if the temperature attains a certain height, the hand may close an
electric contact, which causes a bell to sound. The cavity filled with a liquid or
gas may also be provided with a tightly fitting piston, which will be put in motion
by the increased pressure. Or a spiral spring sensitive to the heat may be
attached to the frictional part or this part may be caused to act directly upon an
electric contact so as to close the same in consequence of its expansion and so on.
As all the different ways, in which this invention may be carried out cannot be
described here, because the description would then be too long, only the arrange-
ments with the pressure gauge and with the spiral spring respectively will be
explained more particularly as the general application of the invention will be
distinctly understood and result from these two arrangements.
Fig. 1 on the annexed drawing represents a transverse section of a bearing and
Fig. 2 a longitudinal one of a bearing, provided with a pressure gauge. Fig. 3
shows the signal system diagramatically and Fig. 4 a section of a bearing provided
with a spring.
In the top part A of the bearing or in another suitable place, for instance in the
very bush or one of the brasses of the bearing is made a cavity a Fig. 1 filled with
a suitable liquid or gas. The pressure gauge d communicates with said cavity
through an opening, so that the hand of the gauge is caused to turn, when a
pressure is created in the cavity a owing to the running hot of the bearing. The
screw serves as a plug in the filling hole of the cavity as well as for regulating
the sensitiveness of the apparatus. The cavity may also have the shape of a
pipe 6 Fig. 2, being extended and communicating with the pressure gauge. This
pipe is also provided with a screw plug l. The gauge d' is provided with two
hands m and n Fig. 3 of which one indicates on an empirical graduation the
temperature prevailing in the bearing, while the other is adjustable so that it can
by hand be put before any line of division of the dial. The hands are electrically
connected with the conducting wires of an electric bell r, and the hands being
directly one above the other the circuit will be closed and the bell sound. The

page_text: pressure gauge can thus be adjusted for signalling at a certain temperature.
B designates the battery and a box with numeral flaps corresponding to the
differently numbered bearings and indicating the bearing giving the signal.
According to Fig. 4 a spiral spring fis mounted on the bearing, this spiral
spring being enclosed in a casing and supporting a hand m visible from the
outside of the casing. Even an ordinary metallic spring changes its form at a rise
of temperature, so as to cause the hand to turn, but if a greater motion of the hand
is desired, the spring may, in the known manner be made of a strip composed of
two layers of metals with different co-efficients of expansion. The hand may, as
already stated, be arranged so as to close an electric contact, thereby causing a
bell to sound at a certain turn of the hand.
The arrangement of a pressure gauge with a pipe, Fig. 2, is very suitable in old
bearings, as it is only necessary to bore a hole at a couvenient place on the bearing
and to introduce the pipe in said hole. In case that the bearing material is porous
so as not to be sufficiently impermeable for preventing the passing off of a gas or
a liquid, the pipe, shown in Fig. 2, may also be used.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
. I claim is :-
1. In shaft bearings, slide valves and other parts in frictional contact, an
arrangement for signalling or otherwise indicating that the said parts are running
hot, characterized thereby that it. is brought in action by the expansion, caused by
said heating, of the parts next to or in the neighbourhood of the surfaces in
frictional contact with each other.
2. The arrangement stated in Claim 1, and carried out in such a way that a
pressure gauge communicates either with a cavity situated in any of the parts
being near the surfaces in frictional contact with each other or with a pipe
introduced into said parts, this cavity pipe being filled with a liquid or gas, the
hand of the pressure gauge being put into the circuit of an electric signal
apparatus, which circuit will be closed by the hand, when this reaches a certain
point on its way.
3. The arrangement stated in Claim 1, and carried out in such a way, that one
of the parts situated near the surfaces in frictional contact with each other is
provided with a cavity filled with a liquid or gas, into which is placed a piston or
the like, which will be put in motion by the heated liquid or gas thereby
signalling the running hot at the place of friction.
4. The arrangement stated in Claim 1, carried out in such a way, that a suitably
bent spring is attached to some of the parts near the surfaces in frictional contact
with each other, this spring being sensitive to heat in such a manner as to change
its shape, when being heated, thereby signalling, by means of a hand fixed to the
same and an electric bell, the running hot at the place of friction.
Dated this 7th day of May 1896.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.