Improvements in Electrical Apparatus for Indicating the Heating of Bearings, and for Stopping Trains when their Bearings are Heated.
Year: 1891

page_text: Date of Application, 17th Aug., 1891-Accepted, 26th Sept., 1891
COMPLETE SPECIFICATION.
Improvements in Electrical Apparatus for Indicating the Heating
of Bearings, and for Stopping Trains when their Bearings are
Heated.
A communication to me from ANTON BACKHAUS, of Sachsen-Altenburg, in the
Empire of Germany, Engineer.
I, EDMUND EDWARDS, of the firm of Edwards and Co., Patent Agents and
Engineers, of 35, Southampton Buildings, Chancery Lane, in the County of
Middlesex, 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 and accompanying drawing, that is to say :—
My present invention relates to an improved arrangement of apparatus by which
when the temperature of any revolving axle, more especially the axle of a railway
carriage, exceeds a determined degree, an automatic electric signal is given by
which such overheating is indicated, and if necessary its cause can be removed.
The invention is applicable to revolving shafts and axles of all kinds.
The dangers which are likely to arise from the overheating of the axles of
railway carriages are so well known that it is unnecessary to point out the
importance of any invention providing security against them.
The accompanying drawing is in illustration of the present invention.
Figure 1 is a longitudinal section and Figure 2 a vertical section.
In the axle box or bearing L a thermometer A is inserted which touches the
brass or bush S and is contained in a strong protecting tube or case.
This thermometer contains mercury, or other suitable fluid which is a conductor
of electricity, and from the bulb two branches or tubes rise in which the quicksilver
or other liquid expansible by heat, rises when the thermometer is heated. These
tubes may be marked with graduated scales, and in each of them is arranged an
electrical conducting wire B the lower ends of which are at such a height that the
rising mercury will touch them when it has become heated to the determined
degree. The wires B form the poles of a battery in the circuit of which at one or
more points electrical signalling apparatus or bells are inserted.
It evident that as soon as the mercury or other liquid shall have risen to the
determined point by its expansion through the heating of the shaft or axle,
the connection of the two wires B by the fluid completes the electric circuit so that
the signalling apparatus at once sounds. Brakes put in operation by electro-
magnets may also be included in the circuit, which come into operation directly
the latter is completed by the heating of an axle, so that the revolution of the
axle is checked or stopped and the cause of the overheating can be remedied.
Instead of a thermometer as described the apparatus may be set in action by the
melting of an easily fusible metal. The conducting wires B descend into a
chamber C, in which a piece of easily fusible metal or metallic alloy D, or other
solid body which when melted is a conductor of electricity, is fitted.
The case C is inserted into the cover of the axle box or bearing, and directly
the latter reaches the melting point of the piece D by reason of the overheating of
the axle, the melted metal runs to the bottom of the case and effects a connection
between the ends of the two wires B.
This arrangement can either be used alone or in combination with the
thermometer A. In the latter case the conducting wires of the thermometer may
set in operation the signalling apparatus, and those of the case C the brake, the
thermometer being arranged to operate at a somewhat lower temperature than
the melting apparatus C D, so that the last only comes into use in the event of the
signal not having been noticed.

page_text: The melting arrangement must be renewed after every time that the melting of
the piece D has taken place.
Figure 3 shews a general view of the application of the apparatus to a railway
train, the device being applied to each of the axle boxes. The signal bells E can
be arranged in any convenient positions.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. The application to the bearings of axles and shafts, of apparatus in which the
rise of temperature to a determined degree sets in operation signalling apparatus or
brake devices, by the completion of an electric circuit effected by the expansion of
the liquid in a thermometer, or the melting of a suitable body, substantially as
described and shewn.
2. The arrangement of two or more devices of the kind described and claimed in
Claim 1, such devices being arranged to operate at different degrees of heat and
therefore to come into action successively, substantially as described.
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.