IMPROVEMENTS IN APPARATUS FOR OPERATING CONTINUOUS BRAKES BY COM- PRESSED AIR
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by James Steel at the Office of the
Commissioners of Patents on the 13th October 1876.
JAMES STEEL, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN APPARATUS FOR OPERATING CONTINUOUS BRAKES BY COM-
PRESSED AIR."
This Invention, which relates to improvements in apparatus for operating con-
tinuous brakes on railway trains by means of compressed air, consists of a hollow
cylindrical vessel which is placed horizontally underneath the floor of each vehicle.
This cylindrical vessel is provided with a hollow or recessed or flat cover at each
end, and at or near or between the joint made by the covers with the cylindrical
vessel an elastic diaphragm or bag, preferably corrugated, so as the more easily to
be expanded or contracted or moved horizontally is fixed. Into the centre of each
such elastic diaphragm or bag a metallic draw bar is fixed by a strong metallic joint,
so as to be air-tight, and each such draw bar is coupled by rods to the brake levers at
each end of a railway carriage or other vehicle, so that when the diaphragms or
bags are moved horizontally by the action of the compressed air as herein-after set
forth, the brake blocks are applied or withdrawn. The hole through which the
draw bar passes out of each of the ends or covers of the cylindrical vessel is kept
air-tight by means of an elastic sleeve or tube surrounding it, after the manner
of that set forth in the Specification of the said James Steel, No. 2721, A.D.
1875.
Pipes or passages are provided for the purpose of admitting air to both sides of
the elastic diaphragms or bags, and when the air is on both sides the brakes are
out of action. To apply the brakes the air is withdrawn from the space between
the two diaphragms or bags, which allowing that on the other side to expand forces
the diaphragms or bags inwards, so that they at once put the brake blocks on to the
wheels. To withdraw the brakes con pressed air is re-admitted to the space between
the diaphragms or bags, which forces them and the brake gear connected with
them inwards, that is to say, into their normal position of being off; the valvular
and cock arrangement for the foregoing purposes being substantially the same as
those set forth in the aforesaid Specification No. 2721, A.D. 1875.
It is to be understood that in place of the elastic diaphragms or bags herein-before
described, the cylindrical vessels may be bored and provided with close fitting
pistons and piston rods, but the diaphragm or bag arrangement is preferred as being
Pasien Q11

page_text: much less costly and not requiring the lubrication which pistons and piston rods
require to ensure their efficient action.
Another improvement comprised under the present Invention is applicable not
only to the apparatus herein-before set forth, but also to the other air brake
apparatus for which Letters Patent have been previously granted to the said James
Steel, and to the said James Steel and John McInnes, Nos. 74, A.D. 1874; 623,
A.D. 1875; and 2721, A.D. 1875.
This improvement relates to apparatus for enabling passengers to at once apply
the brakes to a train on an occasion of emergency without incurring the dangerous
delay of first communicating with the guard or driver. It consists of a cock placed
on the air escape side of each piston, diaphragm, or bag, or to the spaces outside
each pair of pistons, diaphragms, or bags, or to pipes attached thereto. The plug of
each cock is fitted with a lever, to which a light chain or strap is connected passing
to the interior of each carriage over the heads of the passengers, and the rim of the
eye of the lever is notched, into the notches of which the point of a pawl or spring
catches. When a passenger pulls the chain or strap for the purpose of allowing the
air to escape in order to apply the brake, the chain hangs loose inside the carriage,
and at the same time the lever on the cock or valve which has been opened is held
up by means of the catch or pawl, so that the carriage and compartment from
which the brake has been applied is at once detected, and thus a check is provided
against the improper use of the passenger brake appliance.