Note: Descriptions are shown in the official language in which they were submitted.
3~3
hOW-PROFILE RAI~W~ CAR RETARD~R
FIELD OF TH~ INVENTION
This invention relates to railway braking apparatus and,
more particularly, to a railroad p~a~matically operated rail-
road car retarder employing a pair of braking ~ars disposedparallel to the track rail which ara carried by a pair of
respective pivoted levers that are opened and closed ~y a
pneumatic pressure piston-cylinder actuator having increased
braking effort to provide greater retardation, having a low-
profile design to provide more vehicle clearance, and havingan improved brake hoa wear and lever spring stop adjusting
features.
BACKGROUMD OF THE I~VE~TIO~
In certain railroad operations, such as, in a classi~i-
cation processing yard, the railway cars or vehicles ofincoming trains are sorted or classified in accordance with
con~ist and destination in a given one of a plurality o~
class or receiving tracks. In hump types of classification
yards, it i~ necessary to control the velocity or speed of
the free-rolling vehicles by suitable braking apparatus.
Generally, the braking apparatus takes the form of power .
operated frictional car retarders having braking bars which
engage and gxip the sides of the passing wheele of the humped
railway vehicles. It will be appreciated that the amount of
retardation or braking effort which is exerted on the pas~ing
wheels by the car retarder is dependent upon the xolla~ility
and the distance that the humped vehicle or cut of vehicles
3~
have to travel -to safely couple with the foregoing vehicle in
the appropriate class track. It has been found that the most
effective retardation occurs when the frictional braking
force is applied to a relatively high point on the sides of
the car wheels. The ensuing benefits of higher wheel contact
braking results in the ability to construct and utiliæe
shorter car retarders in the classification yards. It will
be appreciated that the shortening of the overall length of
the car retarder not only reduces the initial manufacturing
cost~ but also results in the more economical use of the
available space of the yard since the required length of the
approach track is proportionally reduced. Further, it has
been found that the leading edges, corner sill portions, or
side ladders on locomotives and/or vehicles hit the upper
levers and cause damage to the ~ehicl~s and retarders
Further, since some humped cars were unable to clear~freely
pass through the existing car retarders~the amount of retarda-
tion was not always accurately controlled. Thus, it would be
highly advantageous to provide a low-profile car retarder to
allow the unimpeded passage of the locomotives and particu-
larly, the humped cars. An additional problem in conven-
tional braking apparatus resides in the difficulty in making
the necessary adjustments for brake shoe wear and lever stop-
ping. Thus, it is desirable to provide a simple time-saving
method of brake shoe and stop adjustment.
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OBJECTS AND SUMMARY OE THE INVENTION
Accordingly, it is an object of this invention to provide
a new and improved railway braking apparatus for effectively
retarding railway cars.
: 5 Still another object of this invention is to provide a
unique low-profile railway car retarder which allows the
free, unimpeded passage of humped vehicles.
Still a further ob~ect of this invention is to provide a
novel frictional-type of gripping railway brakin~ apparatus
which more effectively retards passing vehicles by having the
brake shoes engage the sides of the wheels at a relatively
higher level.
Yet another object of this invention is to provide an
improved railway car retarder which is readily adjusted for
compensating for brake shoe wear.
Yet a further object of this invention is to provide a new
~ow-profile pneumatically operated car retarder having a
pair of braking bars disposed parallel and on opposite sides
of a track rail which is mounted on cross t.ies, an upper and
a lower pivotal lever, each of the upper and lower pivotal
levers having a platform portion for carrying a respective
one of the pair of braking bars, the lower pivotal lever
having a laterally extending arm, the upper lever initially
extending upwardly and outwardly, and subsequently extendiny
outwardly to form a horizontal arm, a pneumatic piston~
: cylinder actuator, the piston of the pneumatic piston-cylinder
actuator pivotally connected to the cuter extremity of the
laterally extending arm of the lower pivotal lever, the
cylinder of ~he pneumatic piston-cylinder actuator pivo~ally
connected to the outer extremity of the horizontal arm of
the upper pivotal lever, the height of the pivotal connect-
ion of the cylinder with the outer extremity of the horizontalarm of the upper pivotal lever is approximately fifteen inches
from ~the top of the cross ties and is substantially at the
same level as the top of the track rail so that a low sluny
railway vehicle is permitted to freely pass through the car
retarder, and the pneumatic piston-cylinder actuator lifting
the upper pivotal lever and depressing the lower pivotal
lever for moving the pair of braking bars to a closed braking
position when pressure is supplied to the pneumatic piston-
cylinder a~tuator so that the pair of braking bars engage
the opposite sides of the vehicle wheels at approximately .
three and three sixteenth inches from the top of the runni.ng
rail to exert a greater amount of retardation on the passing
vehicle.
An additional object of this invention is to provide a
new and improved railway car retarder which is economical in
cost, simple in construction, dependable in service, easy to
maintain, durable in use, efficient in operation, and facile
to repair.
B_IEF DESCRIPTION OF THE DRAWINGS
The above ohjects and other attendant advantages of the
present invention will become more readily apparent from the
following detailed description when analyzed and considered
in conjunction with the accompanying drawinys, wherein:
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FIG. 1 is a partial top plan view showing a staggered
'.~ dual track railway braking apparatus or car retarder in
accordance with the present invention.
FIG. 2 is an enlarged vertical sectional view of the
car retardex in its opened nonbraking position ~aken sub-
stantially along lines II-II of FIG. 1.
- 4A -
:
3~
Referring now to the drawings, and in particular to
FI~. 1, there is ~hown a seckion or stretch of railway track
which may be located in the ~ump or group area of a railroad
clasqification yard. The trackway includes a pair of running
track rails 1 and 2 which are suitably supported on usual
cross-ties 3. In practice, the track rails 1 and 2 are
mounted on a plurality of rail supports or chairs 4 which
are securely fastened to the tops of cross-ties 3. As sh~wn
in FIG~ 2, the rail support 4 is a prefabricated weldment
structure having a lower base plate 5 and an upper box-like
stand 6. The bearing plate S is situated on t~e tvp of
cross-tie 3 and is bolted in place by through bolts 7. The
rail 1 is disposed on top of stand 6 and is securely held in
place by flange gripping member~ 8 which are bolted to the
top of the stand 6.
As shown in FIG. 1, the brak.ing apparatus or car retarder
is disposed about each of the rails 1 and 2 so that both
wheels of each axle of the railway vehicles may be simul-
taneou31y retarded to control the exiting speed of humped
vehicles. It will be seen that a pair of braking bars 10
and 10' extend parallel and on opposite sides of running rail
1 while a pair of braking bars 11 and 11' extend parallel and
on opposite sides o~ running rail 2. It will be noted that
the entering ends of the braking shoes 10, 10' are of~set in
relation to the entering ends of the braking shoes 11, 11'
to allow the wheels on rail 2 to initially enter the retarder
and then to allow the wheels on rail 1 to subQe~uently enter
3~3
the retarder for a smoother transitional ingreiss. In viewing
FI&. 1, it will be observed tha~ the braXing bars are adapted
to be moved toward and away from the respective running rails
in braking and no~braking positibn~ by a plurality of pneu-
matic power operating units OU. The operatiny units OU for
braking bars 10 and 10' are staggered in relationship to the
operating unit OU for hraking bar~ 11 and 11' which ~acilit~
tes the installation and maintenance of the braking apparatus.
In practice, a source o pneumatic or air pressure (not shown)
0 i8 piped to the individual operating units via trunk line or
conduit 12 which is connected to bran~h pipes 13. The branch
lines or pipes are connected to the respective operating units
~ c~ 5~'- 5
OU via flexible conduits or metal ~u~ 14. Each of the opera~
ting units OU is substantially identical in construction and
includes a pneumatic piston-cylinder actuator or fluid motor
15 and a pair of upper and lawer pivotal levers 16 and 17,
respectively. The upper levers 16 carry the outer braking
bars 10 and 11 while the lower levers 17 carry the inner
braking bars 10' and 11'. The briaking bars lOt 10' and 11, 11'
con~ist of a series of elongated brake beams 20, 20' and 21, 21'
jointed together at their adjoining ends by an overlap connec-
tion. Each of the braking bars also includes a series of
replaceable braXe shoes 22, 22' and 23, 23' which are carried
by the respective brake beams 20t 20' and 21, 21'. As shown in
FIG. 1, the adjacent ends of the brake shoes are stagyered
with respect to the overlapping ends of the brake beams.
Further, the track rail 1 include~ an inner guide rail 24
"
and an outer guide rail 2~' at the exiting end of the retarder
while the track rail 2 includes an inner guide rail 25 and an
outer guide rail 25' at the exiting end of the retarder for
rerailing purposes.
; 5 Turning now to FIG. 2, there is shown one of the opera-
ting units OU of the car retarder which is illustrated in its
opened nonbraking position for allowing the wheel W to pass
through without any retardation or frictional braking. Each
of the operating units OU includes a short-stro~e pneumatic
piston-cylinder actuator 15, which may be of the type shown
and disclosed in our copending application Ser. ~o. 367,012,
filed concurrently herewith, entitled Pneumatic Pressure Actu-
ator, and a pair of pivotal levers 16 and 17. The pneumatic
motor 15 includes a cylinder assemblage 26 having an upper
casting 27, a lower casting 28, and a plastic casing 29 held
together by a plurality of tie bolts 30. The fluid pressure
motor 15 also includes an internal reciprocating piston and
a piston rod 31 which extends through the lower casting 28.
A pipe fitting 18 is threaded in the top of the upper casting
27 for supplying air pressure to the top of the piston by
flexible conduit 14. A pipe fitting 19 is threaded in the
bottom of the lower casting 28 to vent the underside of the
piston to atmosphere-. As shown, the outer extremity of the
upper lever 16 is pivotally connected to a trunnion portion
of the upper casting 27 by a pivot or fulcrum pin 32 while
the outer extremity of the lower lever 17 is pivotally con-
nected to the end of the piston rod 31 by pivot or fulcrum
.~, ' .
,5,~ i.,~,
3~
pln 33. The pivot pins 32 and 33 are loc~ed in position
by retaining eye_pins 34 and 35, respectively, which are
bolted to the respective levers.
It will be seen that the upper and lower levers are
pivoted about a common ulcrum point or pivot pin 37
carried by the associated rail su~ports 4 mounted on tha
two adjacent cros~-ties 3. As shown in FIG. 2, the pivot
pin 37 passes through sleeva beaxings in levers 16 and 17,
and the pin 37 i9 locked in place by retaining eye-pins 38,
each of which is bolted to the respective associated rail
~upport 4. A grease fitting 39 is provided to lubricate
the mutual center bearing of the upper and lower levers
16 and 17 while grease fittings 40 and 41 are provided to
lubricate the respective end bearings of uppar and lower
lever~ 16 and 17. It will be seen that the upper lever 16
initially extends upwardly and outwardly from its journaled
end with pivot pin 37 and that intermediat~ its free end the
lever 17 is bent and extends horizontally, the purpose of
which will be described hereinafter. A platform structure
45 is disposed between the bifurcated arms of upper lever
16 intermediate its pivoted ends. The platform 45 is
preferably a prefabricated weldment which is fixedly
secured to lever 16 by fillet welding the contiguous
surfaces. Also, a bored apertured spring retaining block
46 is fillet welded to each of the outside surfaces of the
bifurcated lever 16 for holding the two resilient stop
- 8 ~
3~
units SUl and SU2~ Each of the spring units includes a bolt
48 extending downwardly with some clearance through an aper-
ture formed in the retaining block 46. A long collar unit 49
is threadedly screwed onto the lower end of the bolt 48.
biasing spring 50 ~urrounds the upper collar portion o~ nut
49 and the lower portion of bolt 48. The spring is entrapped
between the flange portion of nut 49 and a circular collar
provided on the underside of retaining block 46. It will be
seen that the resilient spring 50 is slightly depxessed by
the weight of the lever assembly so that the head of the bolt
48 is spaced rom the top surface 51 of block 46.
It will be seen that the upper surface of platfo~m 45 is
provided with an upstanding lug 53 which includes centrally
a threaded aperture for receiving an adjusting bolt 54. The
outer end of bolt 54 is provided with a hexagonal or square
head 55 to facilitate turning the bolts by means of a wrench.
A lock nut 56 is provided at the end of the adjusting bolt 54
to allow the bolt to be locked in place after adjuætment.
Further, the adjusting bolt 54 i~ provided with an enlarged
head portion 57 which is adapted to engage and cooperate with
bifurcated members or hook portions 58 provided on the outer
edge of the brake beam 20. The platform 45 includes a flat
upper surface 45a which supports the braking bar lOo. As
mentioned above~ the braking bar 10 includes the brake beam
20 and the replaceable bxake shoe 22 which is secured to the
inside vertical surface by threaded bolts or the like. In
viewing FIG. 2, it will be observed that the underside of
~ g _
~g~
the elonga~ed braXe beam 20 is pxo~id~d with a pair of
oppo~ing hook portion~ 20a which are initially aliyned with
a pair of no~ches 45b formed in the opposite ~ide~ of tha
flat upper surface portion A5a. In practice, the adjusting
bolt 54 is suf~icien~ly bac~ed off to allow the enlarged head
57 to be disposed between the two hook portions 58 as well as
to allow the hooXR to become aligned with notches 45b. Under
this condition; the periphery of the hooks easily clears the
edges of notche~ 45b to allow the brake beam 20 to be seated
on the upper flat surface o the platorm for allowing the
brake beam~ 20 to be interlocked with the supporting platform
45. That is, the adju~ting bolt 54 is turned to slide the
braking bar 10 t~ward the track rail 1 so that the tong~ of
the hook~ 20a will b~ situated under projecting ears 45d of
platform 45~ :
Ik will be appreciated that the lower lever 17 include~
a prefabricated weldment platform tructure 45' whic~ is
fixedly ~ecured by fillet welding or the like to the re te
end of the lever 17. ~ike platform 45, the pla~form support
45' includes a 1at upper surface 45a' ha~ing an upstanding
lug 53' welded to the top of support 45. The lug 53' is
centrally bored and threaded to receive a screw-threaded
adjusting bolt 54' which is pxovided with a wrench accommo-
dating head 55' and a locX nut 56'. T~e adjusting bolt 54'
also includes an enlarged head 57' which cooperates with hook
portion 58' to move the braking bar 10' t~ward and away from
the center o the track rail 1. m e brake beam 20' includes
-- 10 ~
3~
a pair of opposing hoo~ portions 20a' which are initlally
aligned with a pair of notches 45b' and subsequently are dis-
posed beneath projecting ears 45d' to interlock the braking
bar 10' with respect to platform 45i.
It will be seen that a resilient spring retu.rn and stop
unit SU3 is also cooperatively associated with the lower lever
17. The spring unit SU3 is disposed within a fabricated hous-
ing 60 formed between the bottom side of the upper plate 45a
and the upper side o* the top plate of lever 17. A cixcular
opening 61 is formed in the top plate of lever 17. The spring
unit SU3 includes a spring bolt 63 havins an enlarged circular
head 63a, a shank 63b, and a shoulder 63c. An inner s~op
spring 64 and an outer return sprlng 65 are disposed about the
shank portion of bolt 63~ A flanged sleeve 66 is disposed on
bolt 63. m e stop spring 64 is trapped between the circular
head ~3a of bolt 63 and the shoulder 63c. The return spring
65 is trapped between the enlarged head 63a o~ bolt 63 and the
top surface o~ end plate 67 which is bolted to the underside
of the top plate o~ the lever 17. A spring stop nut 68 is
threaded onto the bolt 63 while a ~pring lock nut 69 is also
threaded onto the end of bolt 63. As shown, an L,shaped angle
bracket 70 is disposed between the two adjacent cross-ties 3.
An L-shaped angle iron 71 has its vertical leg welded to.each
end of bracket 70 and has its horizontal leg bolted to t~e top
of cross-ties 3 by through bolts 7, one of which is shown in
FIG. 2. The l~wer end of bolt 63 extends downwardly through a
lateral elongated slot 7Oa formed in the angle bracket 70 and
is secured to bracket ~0 b~ stop nut 68 and lock nut 69 which
is held in place by a cotter pin 72.
In describing the operation of the car retarder, it will
be appreciated that the braking bars 10 and 10' are adjusted
to have a six inch gap between the ~pposing faces of the brake
shoes 22 and 22' when the retarder is in its open nonbraking
position and to have a five inch gap ~etween the opposing
wheel engaging surfaces of the brake shoe~ 22 and 22' when
the retarder is in its clos~d braking position. For adjusting
the car retarder in its open position~ a maintainer initially
turns the heads of spring bolts 4~ of spring units SUl and
SU2 which is readily exposed from the top of the retarder
until the distance from the top of cross-ties 3 to the center
of pivot pin 32 is fifteen inches. It will be appreciated
that in the subject low-profile con~iguration, this distance
is approximately ~wenty-five percent less than in previous
frictional car retarders, namely, fifteen inches versus
nineteen and three-quarter inches. ~IUS, the present low-
profile car retarder i5 less likely to impede the free
passage of humped railway cars. For example, low hanging
side car ladders and corner sills will not engage the outer
extremity of the upper lever 16 as was common occurrence in
existing car retarders. It has been found that the railway
cars sway or move from side-to-side as they negotiate their
way from the crest ~f the hump to the ~torage tracks 50 that
~he lower corner side structuxe o the cars previously struck
_ 12 -
the upstanding ends of the upper levers of the prior art car
retarders. Thus r less damage to rolling stock as well as -to
~he retarder proper is realized due to the unique low-profile
structural configuration of the present car retarder. Fuxther,
it will be appreciated that the opened and clo~ed brake shoe
distances are initially adjusted by turning the stop and lock
~ 5~'
nuts ~-a~2-6~' and heads 55 and 55' of khe adjusting bolts
54 and 54'~ Subsequent compensation for braXe shoe wear may
be accomplished by turning the bolt~ 54 and 54' inwardly to
obtain the five inch gap in the closed braking position.
Let us assume that the car retarder is in its opened non-
braking position as show~ in FIG. 2 and that it is desîred
that the retarder be moved to its closed braking position.
~hus, fluid pressure or air is admitted rom the supply source
through lines 12, 13, and 14 to each piston-cylinder actuator
or motor 15. When the fluid pressure enters the cylinder 26,
~he piston begins to move dawnwardly causing the extension of
the piston rod 31. The initial downward movement of the
piston rod 31 causes the lower lever 17 to rotate in a
counterclockwise direction about fulcrum pin 37 thereby
raising and moving the brake shoe 22' to its closed braking
position as shown in phantom in FIG. 2. Further rotational
movement of the l~wer lever 17 is restricted by the spring
stop unit SU3. That is, when the stop spring 64 becomes
fully compressed, it stops any furth~r rotation of lever 17,
and thus the cylinder 26 begins to move up~ardly to cause the
upper lever 16 to rotate in a clockwi~e direction about
_ 13 -
fulcrum pin 37. The upward movement of pi~o~al lever 16
causes the brake shoe 22 to rise and m~e the brake shoe 22
to its closed braking p~sition as denoted by the phantom
lines Ln FIG. 2 when the piston-cylindex actuator reaches
its fully extended position. Thus, the car retarder assumes
its closed braking position so that the brake shoes 22 and
22' will engage and grip the xespective sides of ~he wheel W
or wheels of a railway car traversing the xails 1 and 2~ It
will be seen that the tops of the brake shoes 22 and 22'
engage the sides o~ the wheel W at the height of three and
three-sixteenth inches from the top of running rail 1 which
is effectively on~-quarter inch more than existing conven-
tional car retarders. It has been found that by increasing
the height of fxictional engagement by a quarter of an inch
lS results in a ten percent increase in the retardation or
braking action of the car retarder. ~hus, the overall length
of the car retarder may be proportionally reduced to more
e~ficiently and effectively utilize the master and group
track lengths in a hump~type of classification yard where
space is generally at a premium. That is, in many classi-
fication yards, the amount of straight track lengths in the
master and group areas is ver~ limited so that it is highly
advantageous to have a car retarder as short as possible yet
capable of applying the required maximum braking force on the
passing car wheels. It will also be appreciated that a
shorter length car retarder is not only less costly to
initially purchase but also less expensi~e to subse~uently
_ 14 -
maintain and repair du~ to the les~er num~er o~ operating
unit~ OU and brake ~hoe lengths.
In viewing FI~. 1, it will be ~een that when a vehicle
enters the car retarder at the left a~ indicated by arrow A,
the right wheel~ moving on rail 2 initially engage the brake
shoe~ 23 and 23' and then the left wheel~ moving on rail 1
engage the brake ~hoe~ 22 and 22' due to the staggered arrange-
ment of the braking bar3. Thi8 staggering of the braking
apparatus of rail 2 with respect to the braking apparatus of
rail 1 reduce~ entrance 8hock and jolting to the entering car
and it~ lading.
If it is now desired to move the braking bar~ to their
no~braking positions, it is simply necessary to e~haust the
fluid or air from the piston-~ylinder actuators or fluid
motors 15. In viewing FIG. 2, it will be seen that under
this condition, the upper lever 16 moves in a counterclockwise
direction by gravity and comes to rest when the nut 49 strike~
tha stop boss 51 provided on the bearing plate 5. Then, the
lower lever 17 move~ in a clockwi~e direction about pivot pin
37 under the force of gravity and spring~ 64 and 65 and comes
to re~t when the pi~ton i8 retracted to its fully extended
position within cylinder 26. The spring stop units SUl and
SU2 of the upper lever and spriny ~top unit SU3 of the lower
lever are arranged and designed to permit the levers, motors,
and as~ociated braking bar to ~wing a limited amount about
the fulcrum pin 37~ In e:Efect, the limited amount of swing
permits the brake ~hoes to move or travel approximately
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one-hal of an inch on either ~ide of their:positions 80 khat
the brake shoe~ may adju~t themselves to the various widths
of ~he passing car wheels when the retarder i~ in i~ braking
position. Further, ~he brake ~hoes may al~o adjust themselves
to allow the passage o~ all cars and locomotives when the
retarder i~ in it8 nonbraking po~ition.
Although we have herein sh~wn and described only one
form of our invention, it is understood that various change~,
modification~, and alterations may be made therein within the
spirit and scope of the appended claim~ and without departing
from the spirit and scope of our in~ention.
