Improvements in Means for Cooling Electric and other Brakes.
Year: 1899

page_text: Date of Application, 22nd Dec., 1899-Accepted, 7th Apr., 1900
COMPLETE SPECIFICATION.
Improvements in Means for Cooling Electric and other Brakes.
We, THE BRITISH THOMSON-HOUSTON COMPANY, LIMITED, of 83, Cannon
Street, in the City of London, Electrical Engineers, do hereby declare the nature
of this invention (which has been communicated to us from abroad by Axel
Ekstrom, of Schenectady, in the County of Schenectady, State of New York,
United States of America, Electrical Engineer), and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement:-
-
The present invention relates particularly to the operation of railroad trains
where the brakes must be frequently used under such circumstances that no
opportunity is given for the shoes to cool. In modern railway equipments, using
electric brakes, this may become a serious difficulty, because the coils in the
shoe as the current passes through them add to the heat generated by friction.
These coils are usually held in place by a filling of fusible metal, on a long run,
the heat may become so great as to melt the filling and leave the coil loose in the
shoe, which might be productive of accident to the brake. Under ordinary
circumstances this is not likely to arise, but in some installations, actual and
proposed, with which we are familiar, very long and very steep grades are
employed. Under such circumstances, our invention becomes particularly useful.
We have therefore provided a system of cooling brake shoes, which may be
applied to any device ordinarily used, as well as to the electric brake although,
for the causes mentioned above, it necessarily finds its best application in the
latter. The system, in Brief, consists of a set of pipes with which conducting
channels in the shoes are connected, and a pump or other equivalent apparatus
for driving through the pipes cooling fluid, such as air, oil or water.
These pipes
are provided with ordinary couplings between the cars, and in operation whenever
a long grade is encountered, as soon as the brakes are set, the pump is started
and the fluid kept circulating through the- shoes so that their temperature would
not rise too high.
Of course in many cases air would furnish sufficient cooling, but in those cases
in which the grade is heavy and long, it is better to use a liquid.
The invention is illustrated in the accompanying drawings, in which Fig. 1
is a diagram in side elevation of a train equipped therewith; Figs. 2 and 3 show
different arrangements of the circulating pipes; Fig. 4 is another diagrammatic
side elevation of a train having the invention in a modified form; Fig. 5 is a plan
view of a truck equipped with two motors, having the invention applied to it;
Figs. 67 and 8 are details of ordinary brake shoes; Figs. 9 and 10 are, respec-
tively, a side elevation and section on the line 10-10 of Fig. 9 of an electric
brake shoe.
In Fig. 1, A, B, B, etc., are the cars of the train, A being the electric loco-
motive; C is a pump upon the locomotive, D a reservoir; E is one of the circulat-
ing pipes; F, F are the brake shoes. The arrangement of the system of piping
may be either that shown in Fig. 2 or in Fig. 3. In these figures E, E are the
main longitudinal pipes of the train, provided with couplings E. These pipes

page_text: are connected to the brake shoes by cross pipes e, e¹. The connection of these
pipes will be better understood from the subsequent figures.
In Fig. 4 we show that a tank DI may take the place of the pump C; this would
be connected with the pipes E, E by a stand pipe D2, one side which connects
with the bottom of the tank 11, and the other connects with its side higher up.
With this arrangement, as will be understood, the currents of connection in the
liquid which we prefer to employ would ordinarily be sufficient to keep the brake
cool, and the pump may be dispensed with. This is not, under all circum-
stances, as good an arrangement as that shown in Fig. 1, but it may sometimes
be employed.
In Fig. 5 is illustrated the connection of the side pipes with brake shoes of the
electric type and with auxiliary brake shoes of any other convenient type. In
this figure, M, M are the motors, provided with gear cases G, G; H, H are the
electric brake shoes, the discs against which they bear. Suitable angle
valves f, fcut off the supply of oil or other liquid when it is desired to couple
the pipes E, E, the couplings not being shown, but being of any ordinary form.
Pipes e, e connect with the electric brake shoes H.
A suitable form of brake shoe for our invention is illustrated in Figs. 6 and 7
in side and end elevation, respectively. In these, the pipes e e¹ are shown con-
nected by a pipe f embedded in the tread of the shoe. In a modified form, such
as that shown in side elevation in Fig. 8, this pipe may be embedded in the back
of the shoe, leaving the tread F2 of common form, so that it may be renewed
as often as desired.
In Figs. 9 and 10 the electric brake shoe is illustrated. The shoe is supported
in the ordinary way, now well understood in the art, by lugs H', and carries a
coiled pipe connecting the pipes e e'. The arrangement is best understood
from the section in Fig. 10, in which the coil f¹ are shown as retained in place
by the filling of fusible metal. As shown in Fig. 9, the shoe is divided so as
to be conveniently clamped around the axle by the bolts 2, 12. In order to make
a tight joint between the ends of the pipes h, which is by preference cast into the
metal of the shoe, gaskets of some suitable form of packing are provided, as
shown in dotted lines at ht.
Our invention therefore comprises a system of ready application to existing
or new equipments, of efficient form and one easy to manipulate. We believe
ourselves to be the inventors not only of the system, but of the combination of
apparatus for carrying it into effect, and of the novel brake shoes used with it
as hereinafter claimed.
Having now particularly described and ascertained the nature of our said
invention (as communicated to us from abroad) and in what manner the same is
to be performed we declare that what we claim is:-
1. As a new article of manufacture, an electric brake shoe provided with a
channel or groove for the coils, and having a pipe cast in it forming a channel
for the circulation of cooling fluids.
2. As a new article of manufacture, a divided electric brake shoe, provided
with a channel in each part for the coils, and having a spiral pipe cast in it, with
means for making a tight joint in the pipe at the dividing line of the shoe, and
means for clamping the parts together.
3. In a braking system for an electrically propelled car or train, the com-
bination of electric brake shoes and devices for applying them, with a system
of main pipes running through the train, pipes connected with the main pipes
for cooling each shoe, and means for circulating a cooling fluid through the pipes.
4. As a new article of manufacture, a brake shoe provided with a channel
for circulation of cooling fluid.
5.As a new article of manufacture, an electric brake shoe having a channel

page_text: formed therein for the coils, and another channel for circulation of a cooling
fluid.
6. In a braking system for a tram or train, the combination of brake shoes,
and means for applying them, with means for artificially dissipating the heat
occasioned by their application."
7.—In a braking system, the combination of brake shoes and means for
applying them, with a system of pipes for absorbing the heat of the shoes, and
means for circulating a cooling fluid through the pipes at desired times.
Dated this 12th day of December 1800
OMSON-HOUSTON CO. LTD.
ALFRED CLEMENTS,
Assistant Secretary,
J. J. MANHEIM,
T. R. THOMPSON,
Directors.
THE BRITISH THOMSON-HOUSTON CO. LTD.
ALFRED CLEMENTS,
Assistant Secretary,
J. J. MANHEIM,
T. R. THOMPSON,
Directors.