Improvements in Car Brakes.
Year: 1893

page_text: Date of Application, 30th Aug., 1893-Accepted, 7th Oct, 1893
COMPLETE SPECIFICATION.
[Communicated from abroad by THE NEW YORK AIR BRAKE Co., of
115, Broadway, New York City, U.S.A., Manufacturers.]
Improvements in Car Brakes.
I, REGINALD WALTER BARKER, of Monument Chambers, King William
Street, London, Middlesex, Patent Agent, 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:
-
The object of my invention is to add to the braking power on cars by using a
supplemental cylinder to increase the force after the slack is taken up. This device
is similar to the one for which I am making a separate application for Patent
simultaneously herewith. In that application the ad lition al cylinder is connected
to the train pipe and actuated by air from the train-pipe. In this device the
additional cylinder is connected to the main brake cylinder and actuated by
air from there.
Figure 1 is a plan of the device connected to the ordinary automatic brake system.
Fig. 2 is a sectional view of the actuating valve.
In the drawings 1 represents a train pipe which is connected to suitable means
for actuating an automatic brake system.
2, 3 and 4 are the well known triple valve, auxiliary reservoir and brake cylinder
now in use. The power of cylinder 4 is applied to the brake rigging as usual
through the push rod 5 and lever 6. The pipe 7 connects the valve 8 with the main
brake-cylinder 4. The passage 9 connects valve 8 with additional cylinder 10.
The power of this additional cylinder is communicated to the brake rigging by
means of the piston rod 11, jointed lever 12-13 and pull rod 14 which is attached
to the brake rigging by piu 15. The jointed lever 12-13 turns upon a fixed
fulcrum 16.
Fig. 2 is an enlarged section of valve 8; the opening 17 connects the interior of
the valve case with the brake cylinder 4 by means of pipe 7. The opening 19 is
connected to additional cylinder 10 by passage 9; port 18 is open to the
atmosphere; 20 is a valve controlling port 19.
21 is a piston for actuating valve 20.
22 is a spring to move the piston and valve one way.
The operation is as follows:-
In the normal condition the train pipe 1, triple valve 2, and reservoir 3, are
charged with air at considerable pressure, say seventy pounds. A reduction of
pressure in the train pipe causes the triple valve to act and open communication
between reservoir 3 and main brake cylinder 4, thereby forcing out piston rod 5
and applying the brakes, in a manner well known in the art. With this device added,
as soon as the pressure in main brake cylinder, which is connected to inside of the
valve case 8, exceeds the pressure of the spring 22 upon the piston 21, it causes
piston 21 to shift valve 20 and open a passage through 19 from main brake
cylinder 4 to additional cylinder 10, whereupon the piston rod 11 is forced outward,
causing the arm 12 of the jointed lever to revolve about pin 23 and seize rod 14
between the two jaws of the jointed lever; farther motion of the piston rod 11
produces a stress on pull rod 14 proportionate to the distances from the fulcrum 16
of rod 14 and piston rod 11. This stress is communicated to the brake rigging
through rod 14 additional to the stress of the main piston rod 5. The spring 22
should be of sufficient strength to resist movement of piston 21 until the piston in
cylinder 4 has completed its stroke and taken up all the slack in order that the
stroke of the piston in cylinder 10 may be limited and therefore require but
little air.

page_text: Having now particularly described and ascertained the nature of my said inveu-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
:--
1. In a fluid pressure brake system the combination of a main brake cylinder and
piston; an additional brake cylinder and piston; a clutch mechanism connecting
the piston of the additional brake cylinder with the brake rigging; a passage
connecting the two brake cylinders; and an automatic valve set to open only at a
desired fluid pressure in that passage, all combined and operating substantially as
set forth.
2 The improvements in car brakes substantially as and for the purposes herein-
before described, set forth and illustrated in the drawings annexed.
Dated this 25th day of August 1893.
REGINALD W. BARKER.