Improvements in or relating to Railway Brakes.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in or relating to Railway Brakes.
I, WILLIAM PELHAM BULLIVANT, of 72, Mark Lane, in the City of London,
Gentleman, do hereby declare the nature of this invention to be as follows:
-
My invention relates to railway brake apparatus of the class in which jaws
carried on a locomotive brake van, or other vehicle, are operated to grip either
one, or both, of the rails, or a rope, or ropes, or other stationary device or devices.
My said invention is particularly applicable for use on railways having a steep
gradient, and it has for its objects to provide means whereby the gripping, and
the necessary lowering and raising of the jaws into, and out of, their operative
position, can be effected at the requisite times by steam, or other motive agent,
and means whereby the said apparatus is prevented from operating at the
junctions and other parts where the rail, or rails, or its, or their, equivalent, can-
not be gripped.
I will describe an arrangement according to my invention as being operated
by steam and arranged on a locomotive for gripping both of the rails, but it is
to be understood that the invention is not limited thereto.
I provide for each rail a pair of jaw levers, or jaws pivotted in a vertically
moveable slide, and having connected to their upper ends the lower and outer ends
of two toggle links whose upper ends are pivotted, by a pin guided in the slide,
to the rod of a piston raised and lowered by steam pressure. The said slide is
free to move in a rigid frame fixed to the locomotive and is provided with buffers
for absorbing shock and for supporting the slide in its lowest position. To the
frame is pivotted a segmental dog, or cam, connected, by a slot and pin, to the
piston rod in such manner that the said dog, or cam, will always be moved
angularly when the piston rod is raised and lowered. The said dog, or cam,
engages with the upper part of the slide to ensure that the jaws and slide shall
move as one piece during the time that the said jaws are being lowered into
their operative position; that is to say, during the first part of the downward
stroke. When the jaws reach this position the further descent of the slide is
arrested by the aforesaid buffers, and the dog, or cam, having also reached a
portion of the slide curved concentrically with the pivot of the said dog, or cam,
the piston rod descends independently of the slide and thereby causes the jaws
to be closed upon the rail.
During the releasing operation of the brake the dog or cam, first prevents the
slide from ascending and thereby ensures the jaws opening to disengage from
the rail and then releases the slide so that it, and the jaws ascend together away
from the rail.
The valve for controlling the supply and exhaust of steam to and from the
cylinder is connected to a weighted lever having a downwardly extending arm
carrying a roller adapted to engage with obstructions placed at those parts of
the track at which it would be dangerous, or undesirable, that the brakes should
be applied. To this weighted lever is attached by a pin-and-slot-connection, the
.

page_text: brake controlling gear consisting, preferably of a vertically adjustable nut and
a screwed shaft and lever handle under the control of the brakesman.
In the normal working of the apparatus the weighted lever is maintained in
its raised position by the brake-controlling-gear, the lower end of each of the
steam cylinders being fully open to the steam supply and the before mentioned
jaws are thereby supported in their raised, or inoperative positions. When the
brakes are to be applied, the brake-controlling gear is operated so as to release
the weighted levers which then immediately descend and cause the steam to be
admitted above, and exhausted from below the pistons so as to force down the
pistons and piston rods and thereby cause the jaws to grip the rails as herein-
before described. Should this operation however be applied, or if applied fail
to stop the locomotive, before the locomotive reaches a junction, or the like, the
before mentioned obstruction in the track raises the weighted levers and thus
temporarily causes the brake jaws to ascend into their inoperative positions the
brakes being afterwards automatically reapplied when the end of the obstruction
is reached and the weighted lever thereby again allowed to descend.
The pivots of the jaws are free to adjust themselves in a horizontal direction
in the slides so as to compensate for sideway displacement of the locomotive on
the rails due to curves for example.
To enable the brakes to be maintained in in-operative positions when the loco-
motive is not under-steam stops are provided for supporting the pistons in the
raised position.
11
13
1000
Improvements in or relating to Railway Brakes.
I, WILLIAM PELHAM BULLIVANT, of 72, Mark Lane, in the City of London,
Gentleman, 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:-
-
My invention relates to railway brake apparatus of the class in which jaws
carried on locomotive, brake van, or other vehicle, are operated by steam or other
motive agent to grip either one, or both, of the rails, or a rope, or ropes, or other
stationary device, or devices.
My said invention is particularly applicable for use on railways having a steep
gradient, and it has for its object to provide means whereby the said apparatus
is prevented from operating at the junctions and other parts where it is not
desirable that the rail, or rails, or its or their, equivalent, should be gripped. I
will by reference to the accompanying drawings describe an arrangement accord-
to my invention as being operated by steam and arranged on a locomotive for
gripping both of the rails, but is is to be understood that the invention is not
limited thereto.
In these drawings:-Fig. 1 is a vertical section of the apparatus, Fig. 2 is a
vertical section taken at right angles to Fig. 1 and Fig. 3 is an elevation shewing
the apparatus as applied to the vehicle only part of which latter is represented.
I provide for each rail a pair of jaw levers, or jaws A pivotted in a vertically
moveable slide B, and having connected to their upper ends the lower and
outer ends of two pairs of toggle links C, whose upper ends are pivotted by a
pin D, guided in the slide B to the rod k of a piston K¹ raised and lowered in a
cylinder K by steam pressure. The slide B is free to move in a rigid frame E

page_text: fixed to the locomotive, and is provided with buffers F absorbing shock and for
supporting the slide in its lowest position. To the frame E is pivotted a
segmental dog, or cam G connected, by a slot g and pin gl, to the piston rod k
in such manner that the said dog, or cam, will always be moved regularly when
the piston rod is raised and lowered. The dog or cam G engages with the upper part
of the slide B to ensure that the jaws A, and slide shall move as one piece
during the time that the said jaws are being lowered into their operative posi-
tion that is to say, during the first part of the downward stroke. When the
jaws A, reach this position, the further descent of the slide B is arrested by the
aforesaid buffers F and the dog or cam G having also reached a portion 6 of the
slide B curved concentrically with the pivot H of the said dog or cam, the piston
rod k descends independently of the slide B and thereby causes the jaws A to
be closed upon the rail X. During the releasing operation of the brake, the dog,
or cam G first prevents the slide B from ascending and thereby ensures the jaws A,
opening to disengage from the rail X and then releases the slide so that it, and
the jaws ascend together away from the rail.
The valve J Fig. 3 for controlling the supply and exhaust of steam to and from
the cylinder K is connected to a weighted lever L having a downwardly extending
arm carrying a roller M adapted to engage with obstructions such as N (partly
shewn by dotted lines in Fig. 3,) placed at those parts of the track at which it
would be dangerous, or undesirable, that the brakes should be applied. To this
weighted lever L is attached by a pin and slot connection /, the brake
gear consisting, preferably, of a vertically adjustable nut and a screwed
controlling
shaft O, and lever handle 02, under the control of the brakesman.
In the normal working of the apparatus the weighted lever L is maintained in
its raised position by the brake-controlling-gear, the lower end of each of the
steam cylinders K (one over each of the rails) being fully open to the steam supply
and the before mentioned jaws A are thereby supported in their raised or inopera-
tive positions. When the brakes are to be applied the brake controlling gear
is operated so as to release the weighted leyer L which then immediately descends
from the position shewn in dotted lines to the position shewn in full lines in
Fig. 3 and through the valve J causes the steam to be exhausted from below the
pistons K and steam. from the boilers admitted above the pistons so as to
force down the rods and thereby cause the jaws A to grip the rails X as herein-
before described. Should this operation however fail to stop the locomotive,
before the locomotive reaches a junction, or the like, the before mentioned
obstruction N in the track raises the weighted lever L and thus temporarily causes
the brake jaws A to ascend into their inoperative positions the brake being after-
wards automatically reapplied by the descent of the weighted lever L which
operates the valve J when the roller M leaves the obstruction. The pivots P of
the jaws A are free to adjust themselves in a horizontal direction in openings b
in the slides B so as to compensate for sideway displacement of the locomotive
on the rails X due to curves for example.
To enable the brakes to be maintained in inoperative positions when the loco-
motive is not under steam, stops (not shewn in the drawings) are inserted beneath
the buffers F for supporting the pistons K' in the raised position.
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 railway brake apparatus, the combination with jaws adapted to grip a
stationary rail or device extending along a railway track of motor mechanism
opperatively connected with the jaws for causing them to grip and release the
stationary rail or device, and a valve for controlling the operations of the grip-
oing jaws, of mechanism operatively connected with the valve, and obstructions
In the railway track for operating automatically the said mechanism substan-
ially as set forth.

page_text: 2. railway brake apparatus the combination with jaws, adapted to grip a
Stationary rail or device extending along a railway track, motor mechanism opera-
tively connected with the jaws for causing them to'grip and release the stationary
rail or device, a valve for controlling the operations of the gripping jaws, means
for enabling the valve to be actuated by hand, and mechanism adapted to be
automatically operated by obstructions in the railway track substantially as set
forth.
3. The combination and arrangement of parts constituting the railway brake
apparatus substantially as herein before described and illustrated in the accom-
panying drawings.
11: 1411
of 1000
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.