Improvements in Brake Mechanism for Railway and similar Vehicles.
Year: 1896

page_text: Date of Application, 21st Apr., 1896-Accepted, 23rd May, 1896
[Communicated from abroad by CHARLES OLIVER BAIRD, of Darby, City of
Philadelphia, State of Pennsylvania, United States of America, Gentleman.]
Improvements in Brake Mechanism for Railway and similar
Vehicles.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent
Agents, 45 Southampton Buildings, in the County of Middlesex, do hereby
declare the nature of this invention and in what manner the same is to bo
performed to be particularly described and ascertained in and by the following
statement:-
This invention relates to brake mechanism for railway cars, having especial
reference to an improvement in the slack adjusting devices forming the subject of
former Letters Patent dated August 27th 1805 No. 16,092. Such devices, as will
be seen by reference to said Patent are designed to increase the braking power,
and to compensate automatically for wear of the brake shoes, or slack in the
operating gear, of brake mechanism of the type shown therein. The devices, as
defined in said Patent comprehend, in car-braking mechanism, a main brake beam,
a supplementary brake beam, operatively connected with the brake shoes, a brake-
operating lever bung to one of said beams and a movable wedge preferably though
not essentially in the form of an eccentrically-mounted disk, carried by the other
beam, and acted upon by said brake-operating lever in a manner to be advanced
theroby when slackness of gear or wear of the shoes permit such advance, together
with means, such as a pawl and ratchet, for retaining the wedge in its successive
positions of advancement.
The object of the present improvement is to provide means to insure and
facilitate the most effective operation of the wedge or eccentrically-mounted disk
when the lever is actuated; and to this end, the said wedge, shown in my drawings
as a disk, is provided with a fixed toothed portion and the lever is provided with a
co-acting pinion, provision being had for the retraction of the lever independently
of the pinion, as will be hereinafter particularly described and claimed.
In the annexed drawings-
Figure 1 is a plan of a car truck equipped with braking mechanism embodying
my improvement;
Figures 2 and 3 are details, enlarged, of the compensating devices showing the
same in different positions of adjustment.
Figure 4 is a section on the line -x of Figure 2.
A, B are the car axles; A' B', the wheels thereon, and the two brake beams
carrying the shoes a and b respectively.
DF are the supplementary beams adjacent to the main beams D E respectively,
there being hung to each of the latter a lever G which is connected by a rod
(dorf) with the brake operating shaft at the opposite end of the car. The
supplementary beams D' Fare coupled by rods g, the lever G of each main bean
being linked to the corresponding supplementary beam so that if power be supplied
to the lever G of the beam D this beam and its shoes will be forced toward, and
the beam D' will be forced away from the wheels A1; such movement of beams D
being transmitted by the rods to the beam F and thence to the beam F so BN
to draw the shoes of the latter into contact with the wheels B'. Suitably-disposed
springer, serve to retract the main beams from the wheels when the lever.G is
released.
J

page_text: Mounted upon each of the supplementary beams is a movable wedge in the form
of a rotatable eccentrically mounted disk, i, against which the adjacent lever G
bears at a point near its fulcrum, to the end that as the lever is properly moved
there will not only be effected a separation of the main and supplementary brake-
beams, but, if the brake shoes permit it, a further separation due to the turning
of the eccentric or wedge by contact with the bearing face of the lever G, such
face being preferably curved or cone shaped so as to facilitate the turning
movement.
The lever and eccentric are held firmly and effectively in contact with each other
by the action of the springs above referred to.
I
The eccentric is retained in its successive positions of advancement by means
of the co-acting pawl and ratchet m, and hence the excess of separation of the
main and supplementary brake beams which may be permitted by wear of the
brake shoes, is rendered permanent, and the shoes, when the brakes are off, are
normally held in close relation to the wheel trends, so that the brakes may be
always powerfully applied with a minimum movement of the brake wheel or handle
ou the platform of the car.
The construction and arrangement of the parts above described are substantially
identical with the corresponding parts shown and described in the previous Patent
above referred to. Although such mechanism has been generally practical, in its
operation, yet I have found that the mere frictional engagement of the lever and
eccentric disk are not sufficiently positive and effective to ensure absolutely satis-
factory results at all times. Hence to overcome any uncertainty in the action of
the parts, I have provided the eccentric, adjacent to its boaring edge, with a fixed
or integral segmental rack, and have mounted on a stud on lever G, near
the fulcrum point, a rotatable pinion, which gears with the rack and has a
partially rotatable movement irrespective of the movement or the position of the
lever. On the lever is a pivoted pawl that is held yieldingly in engagement
with the teeth of the pinion by means of a spring, the disposition of the pawl
being such that when the lever is operated to apply the brakes, as above described,
the pawl locks the pinion against back movemeut, and, in consequence, the pinion
positively turns the eccentric as and for the purpose above explained.
When the power is removed from the lever, and the main beam is retracted to
relieve the brakes, as before mentioned, the lever G resumes its position for a
succeeding operation, the pawl in such movement riding over the teeth of the
pinion, so as not to turn the latter. Hence, as the brakes are applied from time
to time the pinion is intermittently moved onward should wear or slack in any
part of the break gear be automatically taken up or compensated for.
It will be obvious that the rotatable pinion mounted on the operating lever
will co-act with the ratchet fixedly secured to the eccentrically mounted disk, and
hence secure certainty of action and effectiveness of result in the operation of the
lever and maintain it in its successive positions of advancement.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1. The combination, in a car braking mechanism, of a main brake beam, a
supplementary brake beam, a suitable brake connected therewith, a brake operating
lever hung to one of said beams, an eccentrically mounted disk carried by thu
other bean, a rack on said disk, and a co-acting gear on the lever, substantially
as described.
2. The combination in a car braking mechanism of a main brake beam, a
supplementary brake beam, a suitable brake counccted therewith, a brake operating
lever hung to one of said beams, an eccentrically mounted disk carried by the
other beam, resilient means to maintain said parts in contact, a rack on said disk
aud a co-acting gear on the lever; substantially as described.
3. The combination, in a car braking mechanism, of a main brake beam, a

page_text: supplementary brake beam, a suitable brake connected therewith, a brake operating
lever hung to one of said beams, an eccentrically mounted disk carried by the other
benin, a rack on said disk, a co-acting gear rotatably mounted on the lever, and
means for locking said gear and retaining it in its successive positions of advance-
ment, substantially as described.
4. The combination in a car braking mechanism, of a main brake beam, a
Bupplementary brake beam, a suitable brake connected therewith, a brako operating
lever huing to one of said beams, an eccentrically mounted disk carried by the
other beam, a rack on said disk, a co-acting gear on the lever, and means for
retaining the disk in its successive positions of advancement, substantially as
described.
5: The combination, in a car braking mechanism, of a main brake beam, a
supplementary brake beam, a suitable brake connected therewith, a brake operating
lever hung to one of said beans, an eccentrically mounted disk on the other beam,
a rack on said eccentric, a piuion rotatably mounted on the lever, and a pawl thereon
co-acting with the pinion, substantially as described.
Dated this 21st day of April 1896.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.