Improvements in Car-brakes.
Year: 1889

page_text: Date of Application, 21st May, 1889-Accepted, 22nd June, 1889
COMPLETE SPECIFICATION.
[Communicated from abroad by THE LAWRENCE RAILWAY BRAKE COMPANY, of 280,
Broadway, in the City, County, and State of New York, Manufacturers.]
Improvements in Car-brakes.
I WILLIAM WILLOTT POPPLEWELL of 17 and 18 Southampton Buildings in the
County of Middlesex, Engineer, 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:-
This invention relates to that class of brakes that are operated by vacuum com-
pressed air or other actuating fluid.
The object of this invention is to provide a car brake which is simple in
construction does not occupy much space and which can be applied easily and
rapidly.
In the accompanying Drawings Fig. 1 is a plan view of the improved brake
shewing one way of applying it to the brake beams.
Fig. 2 is a vertical transverse sectional view on the line, Fig. 1 parts being
omitted.
Fig. 3 is a cross sectional view shewing a modified arrangement.
Fig. 4 is a cross sectional view of another modified arrangement.
Fig. 5 is a plan view of Fig. 4 parts being omitted.
Similar letters of reference indicate corresponding parts.
The brake shoes A which may be of any well known construction are attached
to the saddles A' fastened on the ends of the brake beams B.
To the inner side of one of the brake beams B the cylinder or chamber C is
secured in any well known manner, said cylinder or chamber containing the
piston D provided with the piston rod E.
The cylinder is longer than it is wide as shewn in Figs. 1 and 2 and its longer
axis extends in the direction of the length of the brake beam. The cylinder or
chamber is constructed in this shape so as to project but slightly from the top and
bottom of the brake beam but yet have the requisite area to produce the necessary
pressure. If the cylinder or chamber were made circular it would project so far
from the top and bottom of the brake beam as to strike against the projections on
the roadway between the rails.
The rod F flexibly connected with the outer end of the piston rod E is passed
through an aperture in the other or opposite brake beam B and on the projecting
end of said rod the nut G is screwed for the purpose of tightening said rod more
or less.
When by means of an ejector or other suction device connected with the cylinder
or chamber by a pipe applied on a neck a² of the cylinder the air is exhausted from
the space between the inner end of the cylinder or chamber C and the piston D
the pressure of the exterior air presses the piston D in the direction of the arrow ¹
and pulls the rod F in the same direction. The piston D may be pressed in the
direction of the arrow a' by means of compressed air steam or any other operating
fluid. Thereby the brake beams are pressed towards each other and the brake
shoes A are pressed against the rims of the wheels H. In this construction the
brake beams are at the outer sides of the wheels and the beams when the brake is
applied are pressed toward each other.
In the same manner that the shoes press on one wheel each shoe may press on a
separate wheel however, the shoes always moving toward each other.
In many trucks the brake beams are arranged between the wheels as shewn in
Figs. 3. 4 and 5. With such arrangement of the brake beams and shoes thereon it
shoes and beams must move in directions from each other while
is evident that the

page_text: being applied. The cylinder or chamber is in the construction shewn in Figs. 3, 4,
and 5 and in similar constructions also secured on the inner edge of one brake
beam B that is on the edge facing the wheel rims.
The piston rod E is passed through that head of the cylinder or chamber resting
on the brake beam and through an aperture in the beam and is connected by a
push bar F with the other brake beam.
If the air is then exhausted from that part of the cylinder or chamber between
the piston D and the inner head (of the cylinder or chamber the piston is moved
in the direction of the arrow and the brake beam with which the push bar F¹ is
connected is pressed toward the rims of the corresponding wheels and at the same
time the brake beam carrying the cylinder or chamber is pressed by the back
action toward the rims of its corresponding wheels that is each brake beam is pressed
toward a separate set or pair of wheels and the brake beams move from each other
in contradistinction to the construction shewn in Figs. 1 and 2. Instead of passing
the piston rod E through the inner head of the cylinder or chamber it can be passed
through the outer head and is connected by a yoke M and bar T2 with that brake
beam opposite the one to which the cylinder or chamber is secured.
With this construction also will the brake beam be pressed toward the corresponding
wheels and from each other when the air is exhausted from the cylinder in the
manner described.
It will be observed that in all the constructions shewn the cylinder or chamber
is secured on that edge of the brake beam facing the wheels and thus does not
interfere with any parts of the truck or car-frame.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The combination with two brake beams carrying shoes which are adjacent to the
rims of wheels, of a brake cylinder or chamber secured to the inner edge of one
brake beam, a piston in said cylinder or chamber and mounted to move while
operating toward the inner edge of the brake-beam to which the cylinder or chamber
is secured and a rod or bar connecting said piston with the other brake beam, the
brake beams being mounted to move toward and from each other substantially as
set forth.
Dated thin 01st day of May 1880
POPPLEWELL & Co.,
Agents for the Applicant.