Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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VEHICLE CARRYING RAIL ROAD CAR WITH
REDUCED SLACK
Field of the Invention
This invention relates to the field of rail road cars for carrying wheeled
vehicles.
Background of the Invention
Railroad flat cars are used to transport highway trailers from one place to
another in what is referred to as intermodal Trailer-on-Flat-Car (TOFC)
service.
TOFC service competes with intermodal container service known as Container-on-
Flat-Car (COFC), and with truck trailers driven on the highway. TOFC service
has
been in relative decline for some years due to a number of disadvantages.
First, for distances of less than about 500 miles (800 km), TOFC service is
thought to be slower and less flexible than highway operation. Second, in
terms of
lading per rail car, TOFC tends to be less efficient than Container-on-Flat-
Car
(COFC) service, and tends also to be less efficient than double-stack COFC
service in
which containers are carried on top of each other. Third, TOFC (and COFC)
terminals tend to require significant capital outlays. Fourth, TOFC loading
tends to
take a relatively long time to permit rail road cars to be shunted to the
right tracks, for
trailers to be unloaded from incoming cars, for other trailers to be loaded,
and for the
rail road cars to be shunted again to make up a new train consist. Fifth,
shock and
other dynamic loads imparted during shunting and train operation may tend to
damage
the lading. It would be advantageous to improve rail road car equipment to
reduce or
eliminate some of these disadvantages.
As highways have become more crowded, demand for a fast TOFC service
has increased. Recently, there has been an effort to reduce the loading and
unloading
time in TOFC service, and an effort to increase the length of TOFC trains.
There are
two methods for loading highway trailers on flat cars. First, they can be side-
loaded
with an overhead crane or side-lifting fork-lift crane. Loading with overhead
cranes,
or with specialized fork-lift equipment tends to occur at large yards, and
tends to be
capital intensive.
The second method of loading highway trailers, or other wheeled vehicles,
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onto rail road cars having decks for carrying vehicles, is by end-loading. End-
loading, or circus loading as it is called, has two main variations. First, a
string of
cars can be backed up to a permanently fixed loading dock, typically a
concrete
structure having a deck level with the deck of the rail cars. Alternatively, a
movable
ramp can be placed at one end of a string of rail car units. In either case,
the vehicles
are driven onto the rail road cars from one end. Each vehicle can be loaded in
sequence by driving (in the case of highway trailers, by driving the trailers
backward)
along the decks of the rail road car units. The gaps between successive rail
car units
are spanned by bridge plates that permit vehicles to be driven from one rail
car unit to
the next. Although circus loading is common for a string of cars, end-loading
can be
used for individual rail car units, or multiple rail car units as may be
convenient.
One way to reduce shunting time, and to run a more cost effective service is
to
operate a dedicated unit train of TOFC cars whose cars are only rarely
uncoupled.
1 S However, as the number of units in the train increases, circus loading
becomes less
attractive, since a greater proportion of loading time is spent running a
towing rig
back and forth along an empty string of cars. It is therefore advantageous to
break the
unit train in several places when loading and unloading. Although multiple
fixed
platforms have been used, each fixed platform requires a corresponding
dedicated
dead-end siding to which a separate portion of train can be shunted. It is not
advantageous to require a large number of dedicated parallel sidings with a
relatively
large fixed investment in concrete platforms.
To avoid shunting to different tracks, as required if a plurality of fixed
platforms is used, it is advantageous to break a unit train of TOFC rail road
cars on a
single siding, so that the train can be re-assembled without switching from
one track
to another. For example, using a 5000 or 6000 ft siding, a train having 60
rail car
units in sections of 15 units made up of three coupled five-pack articulated
cars, can
be split at two places, namely fifteen units from each end, permitting the
sequential
loading of fifteen units per section to either side of each split. Once
loaded, the gaps
between the splits can be closed, without shunting cars from one siding to
another.
Use of a single siding is made possible by moving the ramps to the split
location,
rather than switching strings of cars to fixed platforms.
In using movable ramps for loading, the highway trailers are typically backed
onto the railcars using a special rail yard truck, called a hostler truck.
Railcars can be
equipped with a collapsible highway trailer kingpin stand. When the highway
trailer
is in the right position, the hostler truck hooks onto the collapsible stand
(or hitch) and
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pulls it forward, thereby lifting it to a deployed (i.e., raised) and locked
position. The
hostler truck is then used to push the trailer back to engage the kingpin of
the hitch.
The landing gear of the highway trailer is lowered, and, in addition, it is
cranked
downward firmly against the rail road car deck as a safety measure in the
event of a
S hitch failure or the king pin of the trailer is sheared off Once one trailer
has been
loaded, the towing rig, namely the hostler truck, drives back to the end of
the string,
another trailer is backed into place, and the process is repeated until all of
the trailers
have been loaded in the successive positions on the string of railcars.
Unloading
involves the same process, in reverse. In some circumstances circus loaded
flat cars
can be loaded with trucks, tractors, farm machinery, construction equipment or
automobiles, in a similar manner, except that it is not always necessary to
use a
towing rig.
From time to time the train consist may be broken up, with various highway-
trailer-carrying rail road cars being disconnected, and others being joined.
Bridge
plates have been the source of some difficulties at the rail car ends where
adjacent
railroad cars are connected, given the nomenclature "the coupler ends".
Traditionally,
a pair of cars to be joined at a coupler would each be equipped with one
bridge plate
permanently mounted on a hinged connection on one side of the car, typically
the left
hand side. In this arrangement the axis of the hinge is horizontal and
transverse to the
longitudinal centerline of the rail car.
Conventionally, for loading and unloading operations, the bridge plate of each
car at the respective coupled end is lowered, like a draw bridge, into a
generally
horizontal arrangement to mate with the adjoining car, each plate providing
one side
of the path so that the co-operative effect of the two plates is to provide a
pair of
tracks along which a vehicle can roll. When loading is complete, the bridge
plates are
pivoted about their hinges to a generally vertical, or raised, position, and
locked in
place so that they cannot fall back down accidentally.
Conventionally, bridge plates at the coupler ends are returned to the raised,
or
vertical, position before the train can move, to avoid the tendency to become
jammed
or damaged during travel. That is, as the train travels through a curve, the
bridge
plates would tend to break off if left in the spanning position between the
coupler
ends of two rail road cars. Since bridge plates carry multi-ton loads, they
tend to have
significant structure and weight. Consequently, the requirement to raise and
lower the
bridge plates into position is a time consuming manual task contributing to
the
relatively long time required for loading and unloading. Raising and lowering
bridge
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plates may tend to expose rail-yard personnel to both accidents and repetitive
strain
injuries caused by lifting.
It would be advantageous to have (a) a bridge plate that can be moved to a
storage, or stowed, position, with less lifting; (b) a bridge plate system
that does not
require the bridge plate to be moved by hand as often, such as by permitting
the
bridge plate to remain in place during train operation, rather than having to
be
lowered every time the train is loaded and unloaded, and raised again before
the train
can move.
Further, a rail road car may sometimes be an internal car, with its bridge
plates
extended to neighbouring cars, and at other times the rail road car may be an
"end"
car at which the unit train is either (a) split for loading and unloading; (b)
coupled to
the locomotive; or (c) coupled to another type of rail road car. In each case,
the
bridge plate at the split does not need to be in an extended "drive-over"
position, and
should be in a stowed position. Therefore it is advantageous to have a rail
car with
bridge plates that can remain in position during operation as an internal car
in a unit
train, and that can also be stowed as necessary when the car is placed in an
end or
split position.
However, a bridge plate that is to be left in place to span a gap between
adjacent releasably coupled vehicle carrying rail road cars while the train is
moving
must be able to accommodate relative pitch, yaw, roll and slack action motions
between the coupler ends of two adjacent cars during travel. For example, when
a
train travels through a curve, the gap spanned by the bridge plate on the
inside of the
curve will shorten, and the gap spanned by the bridge plate on the outside of
the curve
will lengthen. When passing over switches, the coupler ends of adjacent
railroad cars
may be subject to both angular and transverse displacement relative to each
other. All
of these displacements are complicated by the need to tolerate slack action.
Slack
action includes not only the actual slack in the couplers themselves, but also
the run-
in and run-out of the draft gear, (or sliding sills, or end of car cushioning
devices) of
successive rail cars in the train. This combination of displacements does not
occur at
the articulated connectors between units of an articulated rail road car
(which are
joined at a common, virtually slackless pin), but does occur at the coupler
ends. If the
vehicle carrying rail road cars have long travel draft gear, such as sliding
sills or long
travel end of car cushioning (EOCC) units, the potential range of motion that
would
have to be tolerated by stay-in-place bridge plates at the "drive-over"
coupler ends of
railroad cars would be quite large relative to the nominal gap to be spanned
with the
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cars at an undeflected equilibrium on straight, flat track.
One approach is to reduce the amount and type of train motion to which stay-
in-place bridge plates may be subjected. It is advantageous to reduce the
amount of
$ slack in the releasable coupling, as by using a low slack or slackless
coupler, and to
reduce the travel in the draft gear, as by using reduced travel draft gear. In
addition,
reduction in overall slack action in the train has a direct benefit in
improving ride
quality, and hence reducing damage to lading.
One way to reduce slack action is to use fewer couplings. To that end, since
articulated connectors are slackless, and since the consist of a unit train
changes only
infrequently, the use of articulated rail road cars significantly reduces the
slack action
in the train. Some releasable couplings are still necessary, since the consist
does
sometimes change, and it is necessary to be able to change out a car for
repair or
1$ maintenance when required.
Reduction in the travel of draft gear or end-of car cushioning units (EOCC)
runs directly counter to the development of draft gear since the 1920's or
1930's.
There has been a long history of development of longer travel draft gear to
provide
lading protection for relatively high value lading requiring gentler handling,
in
particular automobiles and auto parts, but also farm machinery, or tractors,
or
highway trailers. There are, or were, a number of factors that led to this
tendency.
First, if subject to general classification in a switching yard, the vehicle
carrying rail
road cars could be coupled to other types of car, rather than merely other
vehicle
2$ carrying cars. As such, they would be subject to slack run-in (i.e, buff)
loads imposed
by grain cars, gondola cars, box cars, centerbeam cars, and so on. That is,
they were
exposed to buff loads from cars having the full range of slack of Type-E
couplers, and
the full range of travel of conventional draft gear. Second, if subject to
flat switching,
the often less than gentle habits of rail yard personnel might lead to rather
high impact
loads during coupling.
In such a hostile operating environment, long travel draft gear or long travel
EOCC units are the customary means for protecting the more fragile types of
lading.
Historically, common types of draft gear, such as that complying with, for
example,
3$ AAR specification M-901-G, have been rated to withstand an impact at $
m.p.h. (8
km/h) at a coupler force of $00,000 Lb. (roughly 2.2 x 106 N). Typically,
these draft
gear have a travel of 2 3/4 tO 3 '/4 inches in buff before reaching the
$00,000 Lb. load,
and before "going solid". The term "going solid" refers to the point at which
the draft
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gear exhibits a steep increase in resistance to further displacement. While
deflection
of about 3 inches at 500,000 lbs. buff load may be acceptable for coal or
grain, it
implies undesirably high levels of deceleration (or acceleration) for more
fragile
lading, such as automobiles or auto parts. If the impact is sufficiently large
to make
, the draft gear "go solid" then the force transmitted, and the corresponding
acceleration imposed on the lading, increases sharply.
Draft gear development has tended to be directed toward providing longer
travel on impact to reduce the peak acceleration. In the development of
sliding sills,
and latterly, hydraulic end of car cushioning units, the same impact is
accommodated
over 10, 15, or 18 inches of travel. As a result, for example, by the end of
the 1960's
nearly all auto rack cars, and other types of special freight cars had EOCC
units.
Further, of the approximately 45,000 auto-rack cars in service in 1997,
virtually all
were equipped with end of car cushioning units. A brief discussion of the
developments of couplers, draft gear and end of car cushioning equipment is
provided
in the 1997 Car and Locomotive Cyclopedia (Simmons-Boardman Books, Inc.,
Omaha, 1997 ISBN 0-911382-20-8) at pp. 640 - 702, with illustrations from
various
manufacturers. In summary, there has been a long development of long travel
draft
gear equipment to protect relatively fragile lading from end impact loads.
Given this historical development, it is counter-intuitive to employ short-
travel, or ultra short travel, draft gear for carrying wheeled vehicles.
However, aside
from facilitating the use of stay-in-place coupler end bridge plates, the use
of short
travel, or ultra-short travel, buff gear has the advantage of eliminating the
need for
relatively expensive, and relatively complicated EOCC units, and the fittings
required
to accommodate them. This may tend to permit savings both at the time of
manufacture, and savings in maintenance during service.
The original need for slack was related, at least in part, to the difficulty
of
using a steam locomotive to "lift" (that is, depart from a standing start) a
long string
of cars, particularly in cold weather, and particularly before the widespread
use of
roller bearings in freight cars. Steam engines were reciprocating piston
engines
whose output torque at the drive wheels varied as a function of crank angle.
By
contrast, presently operating diesel-electric locomotives are capable of
producing
3 5 higher tractive effort from a standing start, without concern about crank
angle or
wheel angle. For practical purposes, presently available diesel-electric
locomotives
are capable of lifting a unit train of identical cars having little or no
slack.
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In that light, it is possible to re-examine the issue of slack action from
basic
principles. The use of vehicle carrying rail road cars in unit trains that
will not be
subject to operation with other types of freight cars, that will not be
subject to flat
switching, and that may not be subject to switching at all when loaded,
provides an
opportunity to adopt a short travel, reduced slack coupling system throughout
the
train. The conventional approach has been to adopt end of car equipment with
sufficient travel to cope with existing slack accumulation between cars. The
opposite
approach, as adopted herein, is to avoid the accumulation of slack in the
first place. If
a large amount of slack is not allowed to build up along the train, then the
need for
long-travel draft gear and other end of car equipment is also reduced, or,
preferably,
eliminated. In that light, it would be advantageous to adopt both a short
travel draft
gear, and a reduced slack, or slackless, coupler, (as compared to AAR Type E).
At
the same time, adopting such a low-slack, reduced travel, system facilitates
provision
of stay-in-place coupler end bridge plates, by reducing the range of motion
that must
be accommodate in service.
Short travel draft gear is presently available. As noted above, most M-901-G
draft gear "go solid" at an official rating travel of 2 3/4" to 3 '/4" of
compression under
a buff load of 500,000 Lbs. Mini-BuffGear, as produced by Miner Enterprises
Inc., of
1200 State Street, Geneva Illinois, appears to have a displacement of less
than 0.7
inches at a buff load of over 700,000 lbs., and a dynamic load capacity of
1.25 million
pounds at 1 inch travel. This is nearly an order of magnitude more stiff than
some M-
901-E draft gear. Miner indicates that this "special BuffGear gives drawbar
equipped
rail cars and trains improved lading protection and train handling", and
further, "[The
resilience of the Mini-BuffiGear] reduces the tendency of the draw bar to bind
while
negotiating curves. At the same time, the Mini-BuffGear retains a high pre-
load to
reduce slack action. Elimination of slack between coupler heads, plus Mini-
Buff
Gear's high pre-load and limited travel, provide ultralow slack coupling for
multiple-
unit well cars and drawbar connected groups of unit train coal cars." Notably,
unlike
vehicle carrying rail cars, coal is unlikely to be damaged by the use of short
travel
draft gear.
In addition to M-901-G draft gear, and Mini-BuffGear, it is also possible to
obtain draft gear having less than I 3/4 inches of deflection at 450,000 Lbs.,
one type
having about 1.6 inches of deflection at 450,000 Lbs. This is a significant
difference
from most M-901-G draft gear.
Furthermore, in seeking a low slack, or slackless train, it is desirable to
adopt
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low-slack, or slackless couplings. Although reduced slack AAR Type F couplers
have been known since the 1950's, and slackless "tightlock" AAR Type H
couplers
became an adopted standard type on passenger equipment in 1947, AAR Type E
couplers are still predominant. AAR Type H couplers are expensive, and are
used for
passenger cars, as are the alternate standard Type CS controlled slack
couplers.
According to the 1997 Cyclopedia, supra, at p. 647 "Although it was
anticipated at
one time that the F type coupler might replace the E as the standard freight
car
coupler, the additional cost of the coupler and its components, and of the car
structure
required to accommodate it, have led to its being used primarily for special
applications". One "special application" for F type couplers is in tank cars.
The difference between the nominal 3/8" slack of a Type F coupler and the
nominal 25/32" slack of a Type E coupler may seem small in the context of EOCC
equipped cars having 10, 15 or 18 inches of travel. By contrast, that
difference,
1 S 13/32", seems proportionately larger when viewed in the context of the
approximately
11/16" buff compression (at 700,000 lbs.) of Mini-BuffGear. It should be noted
that
there are many different styles of Type E and Type F couplers, whether short
or long
shank, whether having upper or lower shelves, as described in the Cyclopedia,
supra.
There is a Type E/F having a Type E coupler head and a Type F shank. There is
a
Type ESOARE knuckle which reduces slack from 25/32" to 20/32". Type F herein
is
intended to include all variants of the Type F series, and Type E herein is
intended to
include all variants of the Type E series having 20/32" of slack or more.
Stay-in-place bridge plates are intended to accommodate the range of travel
defined by the combination of coupler and draft gear, given anticipated
service loads.
While it may be possible to operate telescoping bridge plates, they are
relatively less
advantageous than monolithic bridge plates. First, a telescoping device may
require a
more challenging installation procedure if two sliding parts have to be
inserted in each
other. Second, the telescoping device must be able to telescope, and yet must
also be
able to support the vertical load carried on the slide. A slide with
significant tolerance
may not necessarily support bending moments well, may tend to wear under
repeated
loading, and may cease to slide very well if damaged or bent due to the
vertical loads.
A monolithic beam has no moving parts requiring careful manufacturing
tolerance,
and has no moving parts that may deform and jam in service. Slides may
accumulate
sand and dirt, and may cease to function if water is able to freeze in the
slide.
Summary of the Invention
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In one aspect of the invention there is a combination comprising a first rail
road car for carrying wheeled vehicles and a second rail road car for carrying
wheeled
vehicles. The first rail road car has a first coupler end, and a first
releasable coupler
mounted thereto. The second rail road car has a second coupler end, and a
second
releasable coupler mounted thereto. The first and second releasable couplers
are
mated to form a coupling. The first rail road car has a first deck upon which
wheeled
vehicles can be conducted. The second rail road car has a second deck upon
which
wheeled vehicles can be conducted. The first and second vehicle decks are
longitudinally separated. A gap is defined therebetween. The first coupler end
of the
first rail road car has at least a first bridge plate mounting fitting. The
second coupler
end of the second rail road car has at least a second bridge plate mounting
fitting. The
first and second bridge plate mounting fittings are operable to engage bridge
plates for
spanning the gap to permit wheeled vehicles to be conducted between the first
deck
and the second deck. The coupling has less than 20/32 inches of slack.
IS
In an additional feature of that aspect of the invention the first and second
couplers are chosen from the set of couplers consisting of: (a) AAR Type E
couplers;
(b) AAR Type H couplers; and (c) AAR Type CS couplers. In another additional
feature, the coupling has between 0 and 3/8 inches of slack. In still another
additional
feature, the coupling is slackless. In a further additional feature, the first
rail road car
has a first draft gear, and the first coupler is mounted to the first draft
gear. The
second rail road car has a second draft gear, and the second coupler is
mounted to the
second draft gear. The first draft gear and the second draft gear each have a
full travel
in buff less than 2 I/2 inches at 500,000 lbs. buff load. In a still further
additional
feature, the first draft gear and the second draft gear each have a full
travel in buff less
than 1 inch. In a yet further additional feature, the first draft gear and the
second draft
gear each have a travel in buff between 5/8 and 3/4 inches at 700,000 lbs.
buff load.
In another additional feature, the first draft gear and the second draft are
each Mini-
BuffCrear.
In still another additional feature, a bridge plate is mounted to each of the
first
and second bridge plate mounting fittings in a first position spanning the
gap. In still
yet another additional feature of that aspect of the invention The each bridge
plate is
movable from the first position to a cross-wise stowed position relative to
one of the
rail road cars. In a further additional feature, a bridge plate is mounted
between the
first and second mounting fittings. When so mounted, the bridge plate has a
first
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degree of freedom relative to the first rail road car to accommodate yawing
motion of
the first rail road car relative to the bridge plate, a second degree of
freedom relative
to the second rail road car to accommodate yawing motion of the second rail
road car
relative to the bridge plate and a third, linear, degree of freedom to
accommodate
variation in distance between the first and second bridge plate mounting
fittings while
the first and second rail road cars are travelling as part of a train. In
still yet a further
additional feature, the bridge plate has a linear extension member, and the
linear
extension member provides the third, linear, degree of freedom. In another
additional
feature, the linear extension member includes a guideway. In yet another
additional
feature, the guideway is a slot, and a pin mounted to the second rail road car
is
engaged in the slot.
In still yet another additional feature, a bridge plate is mounted between the
first and second bridge plate mounting fittings in a first position spanning
the gap.
The first rail road car has a first transition plate extending between the
first deck and
the bridge plate. The first transition plate has a surface over which wheeled
vehicles
can be conducted between the first deck and the bridge plate. The first
transition plate
is tolerant of motion of the bridge plate relative to the first deck while the
first and
second rail road cars are travelling in a train. In a further additional
feature, the
second rail road car has a second transition plate extending between the
second deck
and the bridge plate. The second transition plate has a surface over which
wheeled
vehicles can be conducted between the second deck and the bridge plate. The
second
transition plate is tolerant of motion of the bridge plate relative to the
first deck while
the first and second rail road cars are travelling in a train. In still a
further additional
feature, the first transition plate is movable to a raised position clear of
the bridge
plate to permit movement of the bridge plate to a stowed position.
In another aspect of the invention, there is a rail road car for carrying
wheeled
vehicles. The rail road car has a rail car body supported by rail car trucks.
The body
has a first end, a second end and a deck onto which wheeled vehicles can be
conducted from either of the ends. The body has side sills running along, and
bounding, the deck. A portion of each the side sill extends to a level higher
than the
deck to define a trackway for wheeled vehicles therebetween. The first end has
a
draft pocket mounted thereto. The draft pocket has a draft gear assembly
mounted
therein having less than 2 1/2 inches of travel at 500,000 lbs. buff load. A
releasable
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coupler is mounted to the draft gear. The releasable coupler has less slack
than an
AAR Type E coupler.
In an additional feature of that aspect of the invention, the draft gear has
less
than 1 inch of travel. In another additional feature, the coupler is chosen
from the set
of couplers consisting of: (a) an AAR Type F coupler; (b) an AAR Type H
coupler;
and (c) an AAR Type CS coupler. In still another additional feature, the rail
road car
is an articulated rail road car having a plurality of rail car bodies. Each
railcar body is
joined to an adjacent rail car body at an articulated connector. Each rail car
body has
a deck for carrying wheeled vehicles, and intermediate bridge plates mounted
between
the rail car bodies to permit wheeled vehicles to be conducted therebetween.
In yet another additional feature, a bridge plate is mounted to the first end
of
the rail car body and is movable to extend to an adjacently coupled rail road
car for
carrying wheeled vehicles.
In still yet another additional feature, a bridge plate is mounted to the
first end
of the rail car body. The bridge plate is movable to a cross-wise stowed
position
relative to the first end of the rail car body.
In a further additional feature, a bridge plate is mounted to the first end of
the
rail car body. The bridge plate is movable between a length-wise extended
position
and a cross-wise storage position.
In another aspect of the invention, there is a rail road car for carrying
wheeled
vehicles. The rail road car has a rail car body supported by rail car trucks.
The body
has a first end and a second end. A deck extends between the first and second
ends of
the rail car body, upon which deck wheeled vehicles can be end loaded at
either of the
ends. Side sills extend along the deck. At least a portion of the side sills
stand higher
than the deck to define a roadway therebetween along which wheeled vehicles
can be
conducted. A first draft pocket is mounted at the first end of the rail road
car. The
first draft pocket has a first draft gear assembly mounted therein. The first
draft gear
assembly has less than 2 1/2 inches of travel at 500,000 lbs. buff load. A
first
releasable coupler is mounted to the first draft gear. The first releasable
coupler has
less slack than an AAR Type E coupler. A second draft pocket is mounted at the
second end of the rail road car. The second draft pocket has a second draft
gear
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assembly mounted therein. The second draft gear has less than 2 1/2 inches of
travel
at 500,000 lbs. buff load. A second releasable coupler is mounted to the
second draft
gear. The second releasable coupler has less slack than an AAR Type E coupler.
On
straight track, two of the rail road cars can be coupled together by mating
either of
their respective first and second couplers to form a coupling having less
slack than a
coupling of AAR Type E couplers, with their respective corresponding end-
loading
vehicle decks aligned to either side of the coupling so formed.
In an additional feature, the rail road car has a single rail car body having
the
first coupler at the first end thereof, and the second coupler at the second
end thereof.
In another additional feature, a bridge plate is mounted at each of the first
and second
ends thereof. In still another additional feature, a collapsible hitch for
engaging the
king pin of a highway trailer is mounted to the deck. In still yet another
additional
feature, the rail road car is an articulated rail road car. In a further
additional feature
of that aspect of the invention, the rail car body is a first rail car body.
The first end is
a first coupler end. The first rail car body also has a first articulated end
at which it is
joined to another rail car body by an articulated connector. The rail road car
has at
least a second rail car body having a second coupler end. The second rail car
body is
connected to another rail car body of the articulated rail road car at an
articulated
connection. The rail road car has a bridge plate mounted to each of the first
and
second coupler ends.
In another additional feature, each of the bridge plates is movable between a
length-wise position and a cross-wise position relative to its respective
coupler end.
In still another additional feature, each of the bridge plates is movable
between a
length-wise position and a cross-wise position relative to its respective
coupler end.
In yet another additional feature, the rail road car is an articulated rail
road car having
at least two rail car bodies connected at an articulated connector. Each of
the rail car
bodies has a straight through center sill. In a further another additional
feature, each
of the rail road car bodies includes a respective portion of the deck. Each of
the car
bodies has a plurality of longitudinally spaced apart, laterally extending
cross-bearers
supporting the respective portion of the deck.
BRIEF DESCRIPTION OF THE DRAWINGS
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Figure la shows a conceptual side view of a train having several articulated
vehicle carrying rail road cars, in an unloaded condition;
Figure lb shows a portion of the train of Figure la as split for loading;
Figure lc shows the train portion of Figure la in a split configuration ready
for
loading;
Figure ld shows the train portion of Figure la in a partially loaded
condition;
Figure le shows the train portion of Figure la in a fully loaded condition;
Figure if shows portions of the train of Figure la in an assembled condition;
Figure 2a shows a side view of a five-pack articulated railroad car for
carrying
highway trailers as loaded;
Figure 2b shows a top view of the five pack articulated rail road car of
Figure 2a
in an unloaded condition;
Figure 2c shows a side view of the rail road car of Figure 2a in an unloaded
condition;
Figure 3a shows an isometric view of a "B-End" unit of an articulated rail
road
car such as shown in either Figure la or Figure 2a, with middle floor
deck plates removed for clarity;
Figure 3b shows a top view of the articulated rail road unit car of Figure 3a;
Figure 3c shows a side view of the articulated rail car unit of Figure 3a;
Figure 3d shows an underside view of the rail road car unit of Figure 3a;
Figure 3e shows an end view of the articulated rail road car unit of Figure
3a;
Figure 3f shows a mid-span cross-section of the rail road car unit of Figure
3a;
Figure 3g shows an enlarged side detail of the rail car unit of Figure 3a at
the
coupler end of the car;
Figure 3h shows an enlarged top detail of the rail car unit of Figure 3a;
Figure 4a shows a top view of a bridge plate for the rail car unit of Figure
3a;
Figure 4b shows a side view of the bridge plate of Figure 4a;
Figure 4c shows an end view of the bridge plate of Figure 4a;
Figure 4d shows a section of the bridge plate of Figure 4a taken on '4d - 4d';
Figure 4e shows a section of the bridge plate of Figure 4a taken on '4e - 4e';
Figure 5a is a partial isometric view of the bridge plate of Figure 4a in an
extended position relative to the rail car unit of Figure 3a;
Figure 5b is a partial isometric view of the bridge plate of Figure 4a in a
stored
position relative to the rail car unit of Figure 3a;
Figure 5c is a top view of the bridge plate of Figure 5a showing in service
deflection;
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Figure 6a is an isometric view of a transition bridge plate for the rail car
unit of
Figure 3a;
Figure 6b is a top view of the transition bridge plate of Figure 6a;
Figure 6c is a side view of the transition bridge plate of Figure 6a;
Figure 7a is an isometric view of a cam crank of the rail car unit of Figure
3a;
Figure 7b is a side view of the cam crank of Figure 7a;
Figure 7c is an end view of the cam crank of Figure 7a;
Figure 7d is a cross-section of the cam crank of Figure 7a taken on '7d - 7d';
Figure 7e is a view of the cam crank of Figure 7a taken on arrow '7e';
Figure 7f shows a partial cross-section of the rail car unit of Figure 3a
taken on
'7f - 7t' showing the cam crank of Figure 7a installed;
Figure 7g shows a partial sectional view across the rail car unit of Figure 3a
with
the cam crank of Figure 7a installed;
Figure 8a shows a partial side sectional view of two rail road cars having
bridge
plates, as shown in Figure 7a, in a separated position;
Figure 8b shows the rail road cars of Figure 8a in an approach position;
Figure 8c shows the rail cars of Figure 8a as one bridge plate meets a cam
crank;
Figure 8d shows the rail cars of Figure 8a in a coupled relationship;
Figure 8e shows the rail road cars of Figure 8a in an alternate approach
position
to that of Figure 8b;
Figure 8f shows the rail cars of Figure 8e as one bridge plate meets a ca.m
crank;
Figure 9a shows an isometric view of a 'A-End" unit of the articulated rail
road
car of Figure la with middle floor deck plates removed for clarity;
Figure 9b shows a top view of the articulated rail road unit car of Figure 9a;
Figure 9c shows a side view of the articulated rail car unit of Figure 9a;
Figure 9d shows an underside view of the rail road car unit of Figure 9a;
Figure l0a shows an isometric view of an intermediate "C" unit of the
articulated
rail road car of Figure la with middle floor deck plates removed for
clarity;
Figure lOb shows a top view of the articulated rail road unit car of Figure
10a;
Figure lOc shows a side view of the articulated rail car unit of Figure 10a;
Figure lOd shows an underside view of the rail road car unit of Figure 10a;
Figure lla shows a top view of the draft gear at the coupler end of the
articulated
rail road car of Figure 3a;
Figure llb shows a sectional of the draft gear of Figure lla taken on 'llb -
llb';
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DETAILED DESCRIPTION OF THE INVENTION
The description that follows, and the embodiments described therein, are
provided by way of illustration of an example, or examples of particular
embodiments
of the principles of the present invention. These examples are provided for
the
purposes of explanation, and not of limitation, of those principles and of the
invention. In the description, like parts are marked throughout the
specification and
the drawings with the same respective reference numerals. The drawings are not
necessarily to scale and in some instances proportions may have been
exaggerated in
order more clearly to depict certain features of the invention.
In terms of general orientation and directional nomenclature, for each of the
rail road cars described herein, the longitudinal direction is defined as
being
coincident with the rolling direction of the car, or car unit, when located on
tangent
(that is, straight) track. In the case of a car having a center sill, whether
a through
center sill or stub sill, the longitudinal direction is parallel to the center
sill, and
parallel to the side sills, if any. Unless otherwise noted, vertical, or
upward and
downward, are terms that use top of rail, TOR, as a datum. The term lateral,
or
laterally outboard, refers to a distance or orientation relative to the
longitudinal
centerline of the railroad car, or car unit, indicated as CL - Rail Car. The
term
"longitudinally inboard", or "longitudinally outboard" is a distance taken
relative to a
mid-span lateral section of the car, or car unit. Pitching motion is angular
motion of a
rail car unit about a horizontal axis perpendicular to the longitudinal
direction.
Yawing is angular motion about a vertical axis. Roll is angular motion about
the
longitudinal axis.
By way of general overview, Figures la to if illustrate the process of loading
wheeled vehicles onto a train of mufti-unit articulated railroad cars. In this
example,
an assembled train of articulated rail road cars, indicted generally as 20,
includes a
string of three-pack articulated railroad cars 21, 22 , 23 and 24 joined
together with a
two rail car unit articulated rail road car 25, drawn by a locomotive
indicated as 38.
Train 20 travels in a longitudinal direction toward its destination. While
train 20 is
travelling, bridge plates 150 (described more fully below) remain extended in
a
length-wise (i.e., longitudinal) "drive-over" orientation, such as shown in
Figure 5a
below, to span the gap at the releasable coupling between the decks of the
adjacent
rail car units of rail road car 21 and rail road car 22, as well as between
rail road cars
23 and 24, 24 and 25. At the coupled connection between rail road cars 22 and
23,
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bridge plates 150 do not extend lengthwise but are disposed in a stowed, cross-
wise
orientation, transverse to the longitudinal centerlines of the rail road cars,
as shown in
Figure 5b below. Likewise, at the ends of the string of vehicle carrying rail
road cars,
such as adjacent locomotive 38, at the end of train location, (or, in another
context, at
S a car coupled to a different type of freight car), bridge plates 150 are
also placed in
their stowed position, as in Figure 5b. It is preferred that train 20 be a
unit train
composed of vehicle carrying rail road cars, and not coupled to any other type
of car.
In the second, enlarged, partial view of Figure lb, train 20 has arrived at
its
destination, and a rear portion 27 of train 20 has been spotted at a first
location, while
another, more forward portion 29 has been spotted further along the track. The
two
portions are separated by a few hundred feet. Train 20 has been split at the
releasable
coupling between the rear end unit of rail road car 22 and the forward end
unit of rail
road car 23. In the separated position of Figures lb, lc, ld, and le, the
cross-wise
stowed orientation of the bridge plates at the opposing ends of rail road cars
22 and 23
facilitates use of movable ramps 59 for loading, or unloading, of train 20. As
shown
in the succession of views of Figures lc, ld, le and lf, hostler trucks 40 are
used to
move ramps 59 into place adjacent the split, (i.e., uncoupled), ends of rail
road cars 22
and 23, and are then used to back wheeled vehicles, in this instance highway
trailers
42, into place, each highway trailer 42 facing the split, with its king pin
engaging the
hitch plate of a collapsible hitch 112 or 114 (see below), and its landing
gear cranked
firmly down. (Other types of wheeled vehicles, whether automobiles, trucks,
farm
machinery, or buses could be loaded in a similar manner, with or without a
towing
tractor, as may be suitable). At the internal ends of rail road cars 21, 22,
23, 24, and
25, the length-wise extended bridge plates make those ends "drive-over" ends
that
permit highway trailers to be conducted along a continuous path between cars.
When all of the rail car units have been loaded, train 20 is ready. The split,
(or
splits, as the case may be) can be closed by gently shunting the forward and
rearward
portions 29 and 27 together. Train 20 is then ready to depart for its next
destination.
In the example train 20 arrives empty. However, it would be customary for the
loading procedure described to have been preceded by an unloading procedure
for
highway trailer units arriving from the previous depot, as by reversing the
steps of
Figures le, ld, lc and lb.
Describing elements of train 20 in greater detail, coupled units 22 and 23
have
respective first, or "drive over" end units 26, and 28, intermediate
articulated units 30
and 32, and coupled end units 34 and 36. For the purposes of this description,
it can
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be taken that units 26 and 28 are the same, units 30 and 32 are the same, and
units 34
and 36 are the same, but facing in opposite directions. Each of the rail car
units
having a coupler end, namely units 26 and 28, 34 and 36, has an end truck, 35,
mounted under a main bolster at the coupler end, whichever end it may be. Rail
car
units 26 and 30, 30 and 34, 36 and 32, and 32 and 28 are joined together by
articulated connectors indicated generally as 37, mounted over respective
shared
articulated connection trucks 39. Rail car units 34 and 36 are connected by
releasable
couplers 44 and 46. Articulated connector bridge plates 300 (whether left or
right
handed, as described below) span the gaps between rail car units 26 and 30, 30
and
34, 36 and 32, and 32 and 28. With the aid of articulated connector bridge
plates 300,
and movable bridge plates 150, to one side of the split between rail road cars
22 and
23, decks 47, 48, 49, 50, 51, and 52, (and to the other side, 47, 48, 49, 50,
51, 52, 53
and 54) form continuous pathways, or roadways, upon which vehicles can be
conducted in either forward, driving, direction or a reverse, backward
direction. If
additional railroad cars are joined at the opposite ends of railroad cars 22
and 23,
further bridge plates can be employed to extend the length of the pathway.
For the purposes of this description, although Figures la, lb, lc, ld, le, and
if show a locomotive and three-pack or two-pack articulated cars, other
combinations
of articulated cars having any reasonable number of articulation units can be
employed. 2-unit, 3-unit, and 5-unit articulated packs are relatively common.
It will
be understood that the example of Figures la - if is meant symbolically to
represent a
train of any suitable length. Typically, a unit train would include a much
larger
number of cars units, such as 60 or 80 rail car units composed of a
multiplicity of 2, 3,
5 or 6 (or more) unit articulated cars strung together. Such a train can be
directed
onto a siding, with successive portions of the string spotted at different
locations
along the siding, leaving gaps of, typically, 200 or 300 feet between sections
to permit
the placement of ramps as may be suitable. When the cars are loaded, the ramps
are
removed. The locomotive can then reverse, closing each successive gap and
permitting the rail road cars to be reconnected at their respective coupler
ends.
In the example shown, end rail car units 26 of rail road car 21, and 28 of
rail
road car 25, each have a movable bridge plate 150 carried at their uncoupled
ends (in
the case of rail car unit 26, the "uncoupled end" is actually coupled to
locomotive 38,
the context of "uncoupled" meaning an end that is not coupled to another
similar rail
car for carrying vehicles to which a bridge plate would be extended). If a
larger train
were assembled, the uncoupled ends of car units 26 and 28 would be coupled to
mating ends of other articulated cars. When additional cars are joined, the
collapsible
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hitches are oriented in the same direction, namely, all facing toward the
location of
the split. Thus, away from the split, a car unit 26 would mate with a car unit
like car
unit 34, and so on. In a long train there would tend to be more than one
split.
For the purposes of illustration, rail road car 22, which includes rail car
units
26, 30, and 34 will be described in greater detail. It will be appreciated
that a two-unit
articulated rail road car, such as rail road car 25, can be assembled by
joining units 26
and 34 directly together, and that, in general, articulated rail cars of
varying lengths
can be assembled from a pair of ends units, such as units 26 and 34, and any
chosen
number of intermediate units (i.e., cars not having coupler ends) such as unit
30. A
five-pack assembled in this way is shown loaded in Figure 2a, and unloaded in
Figures 2b and 2c. For the purposes of this description, unit 26 is
arbitrarily
designated as the "A-End" unit, unit 34 is the "B-End" unit, and unit 30 is
the "C", or
intermediate unit. In rail road terminology the "B" end of a rail road car is
the
handbrake end, or predominant hand brake end. When several "C" units are
employed in a multi-unit articulated rail road car, as in the five pack of
Figures 2a, 2b
and 2c, each may be referred to as the "C', "D", or "E" unit (and so on if
more units
are used). There are minor structural differences between the intermediate
units, such
as whether one hitch is provided or two, and corresponding cross-bearer and
deck web
reinforcements. For the purposes of this structural description any
intermediate car
unit will be referred to as a "C" unit, and unit 30 will be taken as
representative of
intermediate units in general, whatever their hitch layout may be.
The second end unit (the "B" unit) 34 is shown in Figures 3a, (isometric, with
decking partially removed to reveal deck supporting structure), 3b (side) 3c
(top view,
with decking partially removed to reveal structure) 3d (underframe) and 3e
(coupler
end view). Car unit 34 has a main longitudinal structural member in the nature
of a
main center sill 60 having a draft pocket 62 at one end (i. e., the "coupler
end" portion,
64 of unit 34), and an articulated connector socket in the nature of a
rectangular
fabricated steel box 66 into which one half of an articulated connector 68 is
mounted
at the other end (i.e., the articulated connection end portion, 70 of car unit
34). In
between the coupler end portion 66 and the articulated end portion 70 is a
central
portion, 72, being the mid-span portion of the car between its trucks.
As shown in the offset section of Figure 3f, over the central portion 72, of
unit
34 center sill 60 has the form of a hollow beam having a top flange 74, a
bottom
flange 76, and a pair of spaced apart vertical webs 78, 80. A set of cross-
bearers 82
extend outwardly from roots at the side webs of center sill 60 to laterally
outboard
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ends that meet in lap welded joints with vertical gussets 83 of meet side
sills 84 and
86. Each of side sills 84 and 86 has a hollow rectangular top chord member 90,
an
outer cowling sheet, or web 92, a bottom chord in the form of an angle 94, and
a
cross-bearer flange extension 96 in the form of a bent member welded to the
inner
face of top chord member 90 in a downwardly hanging position, the upward
portion,
or leg of extension 96 lying on the same slope as the top chord web, the
inwardly
extending portion, or leg, of extension 96 lying roughly horizontally to
provide a lip
that is welded to the top flange of the cross-bearer.
Floor panels 100 span the pitches between cross-bearers 84, to provide a
continuous pathway from one end of the car to the other. Each floor panel 100
is
formed from a series of spaced apart, longitudinally extending channels 102,
103, 104
surmounted by a top sheet, or flange 106 whose upper surface 108 forms a path
for
the wheels of vehicles loaded on the car unit. Upper surface 108 is roughly
flush with
top flange 74 of center sill 60, and floor panels 100 and top flange 74 co-
operate to
form deck 47 of rail car unit 34. Side sills 84 and 86, run along the sides of
deck 47.
Top chord member 90 of each of side sills 84 and 86 extends well above the
level of
top surface 108, and serves as a curb to encourage trailers to stay on the
trackway, or
roadway, defined on deck 47 between top chord members 90, as they are backed
along the rail car unit.
Each of side sills 84 and 86 is canted inwardly, such that its lower
extremity,
or toe, is nearer to the rail car longitudinal centerline than the top chord.
The inward
cant of top chord member 90 of side sills 84 and 86 gives this curb an angle
or
chamfer, as shown in Figure 3f, such that a truck tire must ride up the slope
before it
can escape, the chamfer yielding a self centering effect as the tires try to
ride along it.
Although only a few floor panels 100 are shown, it will be appreciated that
floor
panels 100 are located continuously to permit vehicles to be driven over the
car units,
as in Figure 2b.
At either end of the central portion of car unit 34, there are dual purpose
cross-
beams 109, 110 located at longitudinal stations corresponding to the 40 ft
container
pedestal locations of a container carrying rail car.
A first collapsible hitch 112 is also mounted to top flange 74 of center sill
60
in a mid span position for engaging a 28' pup-trailer, if required. A second
collapsible hitch 114 is mounted roughly 4 inches inboard from the truck
center, CL
Truck, at coupler end, end portion 64. The cross-bearer flanges are reinforced
under
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the hitch locations, as shown at 116.
At the coupler end, end portion 64, main center sill 60 of rail car unit 34
becomes shallower, the bottom flange being stepped upwardly to a height
suitable for
being supported on truck 35. Side sills 84 and 86 also become shallower as the
bottom flange curves upward to clear truck 35. Rail car unit 34 has a
laterally
extending main bolster 120 at the longitudinal station of the truck center (CL
Truck),
and a parallel, laterally extending end sill 122 having left and right hand
arms 121,
123 extending laterally between the coupler pocket and the side sills. In
their distal,
or outboard regions, arms 121 and 123 have ramp engagement sockets 125 in the
nature of rectangular apertures, with which prongs 127 of ramp 59 can be
engaged to
align ramp 59 with car unit 34 for loading.
As shown in Figure 7g, top flange 74 of center sill 60 has a downwardly
sloping transition 124 longitudinally outboard of main bolster 120, and a
level,
horizontally extending portion 126 lying outboard thereof, such that the end
portion of
center sill 60 is stepped downward relative to the main portion of top flange
74
inboard of bolster 120. A bridge plate support member, in the nature of an
outboard
horizontal shelf portion 134, includes left and right hand plates 128, 130
that form
upper flanges for, and extend longitudinally inboard of, arms 121 and 123 of
end sill
122 to define bridge plate support members.
A laterally extending structural member, in the nature of a fabricated closed
beam 136 is welded to horizontal portion 126 of center sill 60 between side
sills 84
and 86. Beam 136 has vertical legs 138 extending upwardly of portion 126 and a
horizontal back 140, lying flush with the level of top flange 74 at the
longitudinal
location of main bolster 120. Left and right hand deck plates 141 are welded
to back
140 and extend above tapered portion 130 to terminate at main bolster 120.
Plates 128 and 130 are flush with downwardly stepped horizontal portion 126
of top flange 74, and co-operate with portion 126 to define a continuous shelf
across
(i.e., extending cross-wise relative to) the end of rail car unit 34, outboard
of the end
of deck 47 defined by the longitudinally outboard edge of beam 136. In this
way a
step, depression, shelf, or rebate, or recess 142 for accommodating (or for
receiving) a
bridge plate, is formed in the end of rail car unit 34 adjacent to the coupler
144, upon
which bridge plate 150 can rest, as described below.
When seen from above, as in Figure 3h, the outboard end portions 146 and
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148 of side sills 84 and 86, respectively, are splayed laterally outward to
give a flared
end to the pathway, trackway, or roadway, defined between the curbs of their
respective top chord members 90. The flare is achieved with a mitre, or
chamfer, but
could also be achieved with a smooth curve, and serves to provide a lead-in
for truck
S wheels to the straight curb portions of top chord members 90 and to allow
motion of
the bridge plates during operation, as indicated in Figure 5c.
A gap spanning structural member, or beam, namely bridge plate 150, is
indicated in Figures 4a, 4b, 4c, and 4d. Bridge plate 150 is preferably of
steel
construction, but could be of aluminum, or suitable reinforced engineered
plastics, to
reduce the weight to be manipulated by railyard crews. Bridge plate 150 has
the
construction of a rigid flanged beam, having a top flange, or sheet 152, upon
whose
upper surface 154 vehicles can be conducted. Sheet 152 is backed by a pair of
spaced
apart, longitudinally extending channel members 155 and 156, welded with toes
against sheet 152. A pair of formed angles 158 and 160 are welded laterally
outboard
of channel members 155 and 156, and a plate 162 is welded to span the gap
between
the backs of channel members 155 and 156. In this way plate 162, the backs of
channel members 155 and 156, and the horizontal legs 164 and 166 of formed
angles
158 and 160 act as a bottom flange in opposition to the top flange, sheet 152,
with the
other legs and toes acting as vertical shear transfer webs. A traction
enhancement
means is provided to give bridge plate 150 a non-smooth, or roughened track,
in the
nature of laterally extending, parallel, spaced tread bars 168 welded to the
mid-span
portion of sheet 152.
At one end, defined as the proximal, or inboard end, 170, bridge plate 150 has
a pivot fitting, in the nature of a pair of aligned holes 172, 173 formed in
sheet 152
and plate 162 to define a hinge pin passage. The axis 174 of the passage
formed
through hole 172 is normal (i.e., perpendicular) to upper surface 174 of sheet
152,
and, in use, is ideally vertical, or predominantly vertical given tolerance
and
allowance for yaw, pitch, and roll between the rail road cars. Proximal end
170 is
chamfered as shown at 176, 178 and is boxed in with web members 180, 182.
Although a mitre is preferred for simplicity of manufacture, either end of
bridge plate
150 could have a rounded shape, rather than a mitre.
At the other end, defined to be the distal, or outboard end, 184, bridge plate
150 is bifurcated, having a linear expansion member in the nature of a
longitudinally
extending guideway, or slot, 186, defined between a pair of tines, or toes
188, 190,
each having an external chamfer as shown at 192, 194. The distal ends of
channel
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members 154, 156 are also boxed in at distal end 184 as shown at 196. A web
member, in the nature of a gusset 198 is welded between the facing walls of
channels
155 and 156, adjacent to the groin of slot 186, to encourage toes 188 and 190
to
maintain their planar orientation relative to each other.
As shown in Figures 5a, bridge plate 150 can be mounted in an employed,
drive-over, or length-wise extended position, in which distal end 184 is
located
longitudinally outboard of end sill 122, and in which the longitudinal axis of
bridge
plate 150 is parallel to the longitudinal centerline axis of car unit 34 (on
straight track,
but otherwise depending on pitch and yaw between cars) to permit vehicles to
be
conducted between cars. Bridge plate 150 can also be mounted in a stowed,
lateral,
transverse or cross-wise position, as shown in Figure 5b, in which the
centerline of
bridge plate 150 is perpendicular to the longitudinal centerline of car unit
34.
Shelf portion 134 has a first bore formed therein to one side of longitudinal
centerline of unit 34. A pivot fitting, or mounting fitting, in the nature of
a collar 200
is mounted flush with, or slightly shy of the upper surface of shelf portion
134, at a
first location, indicated as bore 202, for alignment with through hole 172. As
discussed below in the context of Figures 8a - 8c the toe of bridge plate 150
can be
tipped up slightly. To do this, the rear, or longitudinally inboard edge of
shelf portion
134 acts as a fulcrum. A retaining member, in the nature of a hinge pin 204,
is
fabricated from a section of pipe 206 of a size permitting a loose fit within
collar 200
to allow for roll, pitch and yaw between cars. Pipe 206 has a flange 208
mounted at
one end, the proximal or upper end. Flange 208 bears on sheet 152 to prevent
pipe
206 from falling though collar 200. Pin 204 also has a lifting fitting in the
nature of a
internal cross bar 209 mounted at the flanged end. Bar 209 is grasped to
withdraw pin
204 (or 205, below). The distal or lower end of pipe 206 is slotted to accept
a
transverse pin 210, itself held in place by a locking member in the nature of
a cotter
pin, that prevents hinge pin 204 from unintentionally lifting out or collar
200. Shelf
portion 134 also has an abutment, or stop, not shown, welded to the upper
surface of
plate 130 to prevent bridge plate 150 from being pivoted past the stowed
position, and
so preventing the side of bridge plate 150 from hitting cam crank 241
(described
below) inadvertently if transition plates 232 is in the raised position (also
described
below).
When hinge pin 204 is in place, bridge plate 150 is restricted, or
constrained,
within the limits of a loose fit, to a single degree of freedom relative to
rail car unit
34, namely pivotal motion about a vertical axis. The sloppy, or loose, fit of
hinge pin
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204 within collar 200 gives a limited amount of play to permit tipping the
bridge plate
upward during coupling, and to permit sufficient roll, pitch and yaw for
normal
railroad operation. In the preferred embodiment, a nylon (t.m) pad 211 is
mounted to
the underside of bridge plate 150 to provide a bearing surface for riding
against shelf
portion 134. In alternative embodiments other types of relatively slippery,
high
density, or UHMW, polymer materials could be used.
Shelf portion 134 of shear plate 130 has a second bore formed therein offset
to
the other side of longitudinal underside of car unit 34. As shown in Figure
7g,
another collar 200 is mounted to the underside of, and flush with (or, shy of)
plate 128
of shelf portion 134 at a second location, indicated as bore 214, at the same
longitudinal station as bore 202 for alignment with slot 186 when bridge plate
150 is
in the lateral, or storage, position resting fully on shelf portion 134.
Another hinge
pin 205, of the same construction as pin 204 described above, is provided to
secure
bridge plate 150 in the stowed position, the distal end of pin 205 locating in
bore 202
and the proximal end locating in slot 186 defined between toes 188, 190. When
hinge
pin 205 is removed, bridge plate 150 is able to pivot about the hinge formed
by the
co-operation of hinge pin 204, collar 200 and through hole 172.
When a bridge plate such as bridge plate 150 is in the extended (i.e.,
lengthwise, or longitudinal) position, and its distal end (or tip) engages the
adjacent
car, pin 205 is again used, this time to provide a positive, securing,
retaining,
indexing, or alignment member to the engaging fitting, namely slot 186. Slot
186 is
then constrained, within the confines of a loose fit, to permit motion along a
first
linear degree of freedom, namely to slide as the gap between cars shortens and
lengthens as adjacent rail car units yaw, or translate transversely, relative
to each
other, and a rotational degree of freedom relative to the locating pin, i. e.,
pin 205, of
the adjacent car. As above, the loose fit of pin 205 in slot 186 allows for
normal pitch
and roll motion of the cars. As shown in Figure 5c, the combination of a
rotational
degree of freedom at pin 204 of one rail road car, and both rotational and
linear
displacement at pin 205 of the other rail road car, accommodates both curving
and
transverse displacement of the coupler ends relative to each other. That is,
the
interaction of slot 186 with pin 205 provides both a pivot fitting for
accommodating
yawing motion of the adjacent rail road car, but also provides a linear
expansion
member for accommodating variation in distance between the respective vertical
axes
of pin 204 (and, collar 200) of one rail road car, e.g., car 22, and pin 205
(and its
collar 200) of the adjacently coupled rail road car, e.g., car 21.
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When viewed in Figure 4a it can be seen that bridge plate 150 has cut-outs
216, 218 formed in its distal end to accommodate cam crank 241 (described
below)
when bridge plate 150 is in the stowed position, and a pair of hand hold rungs
220,
222 mounted to the chamfer of toes 188, 190 to facilitate pulling of bridge
plate 150
S from the stowed position, and to facilitate tipping the distal end, or toe,
of bridge plate
150 upward, preparatory to coupling two rail car unit coupler ends together.
Left and right hand transition plates are shown in Figure 6a, 6b, and 6c as
230,
232. Each has pivot fittings in the nature of arcuate hinge tangs 234, 236
extending
from proximal edge 235. Hinge tangs 234, 236 locate in corresponding
apertures,
namely rectangular slots 238, 240 (Figure 7g) formed in back 140 of formed
channel
136. Hinge tangs 234, 236 and slots 238, 240 co-operate to permit upward
lifting of
their distal tips by pivotal motion of each of transition plates 230, 232
about a
horizontal pivot axis lying perpendicular to the longitudinal centerline of
rail car unit
34. As above, there is tolerance in the fit of tangs 234, 236 and slots 238,
240 to
allow for normal railcar motion. Transition plates 230 and 232 cover the gap
that
could otherwise exist between the inboard, or proximal end of bridge plate 150
(on
one side, i.e., 230) or the toes of the bridge plate of the adjoining rail car
(on the other
side, i.e., 232) and the end of deck 47 of rail car unit 34. Since transition
plates 230
and 232 are relatively thin (5/8 inch) they do not present a large bump when
highway
trailer wheels encounter them. Transition plates 230, 232 each have a U-shaped
central relief 237 formed in distal portion 239 to avoid fouling pin 204 (or
205).
In the preferred embodiment, the upper surface of bridge plate 150 is roughly
flush with the level of the adjacent end of deck 47, as taken at the height of
the upper
surface of the top flange fabricated cross-beam 136, such that a generally
level
roadway is formed. It is possible to conduct highway trailers from bridge
plates 150
to deck 47 without the use of transition plates 230, 232, but is more
advantageous to
use transition plates. It is also not necessary that the depth of shelf
portion 134
relative to the end of the deck, (i.e., the height of the step) indicated as
Dl, be the
same as the depth of bridge plate 150, indicated as D2. It is advantageous
that the
height differential between the top of bridge plate 150 and the end of deck 47
be
small, such as less than 1 - '/2 inches, and better still, less than '/2 inch
to reduce the
potential bump. The severity of the bump is also reduced by the use of
transition
plates 230, 232, that permit a mismatch in height to be taken up over a modest
longitudinal distance, rather than suddenly.
It is also possible to use a bridge plate support member other than shelf
portion
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134. For example, a cross-beam or cantilevered beam could be used, whether
mounted to end sill 122, center sill 60, side sills 84, 86 or some combination
thereof.
Alternatively a pedestal could be employed having an upwardly protruding pin
in
place of pin 204, and an alternative form of second retainer in place of pin
205, such
as one or more retractable abutments, whether spring loaded or otherwise in
the
manner of spring loaded detents, or a releasable hook or latch, could be used
to
similar effect. The use of a bridge plate kit including bridge plate 150 and
pins 204
and 205 is advantageous since pins 204 and 205 are interchangeable, are used
to
provide motion tolerant retention of the proximal end (by pin 204) and distal
end (by
pin 205) of bridge plate 150 in either lengthwise or cross-wise positions, are
relatively
robust, and are of relatively simple fabrication.
Left and right hand cam cranks are indicated in Figures 3h and 7a to 7g, as
241, 242. Each cam crank is formed from a bent steel bar. Each cam crank has
an
1 S inboard hinge portion 244 and an outboard hinge portion 246 that lie on a
common
hinge axis, 248. As shown in Figures 7f, 7g, inboard hinge portion 244 seats
in an
aperture or socket 245 mounted to the underside of, and at the laterally
outboard edge
of, top flange 72, longitudinally outboard of main bolster 120. Outboard hinge
portion 246 seats in an aperture 247 formed through side sill 84 (or 86, as
the case
may be). Socket 245 and aperture 247 act as hinge fittings within which the
shaft
portions of cam cranks 241 and 242 are constrained to turn. The laterally
outboard, or
distal, end of hinge portion 246 has a torque input fitting, in the nature of
an obliquely
angled transverse bore indicated as slot 249. This angle, b', is greater than
the
outward cant of the side sill web and, in the preferred embodiment illustrated
is about
25 degrees. Slot 249 admits entry of a lever member in the nature of a turning
handle,
or pry bar, by which means railroad personnel can impose a turning torque on
cam
crank 241, 242. As shown, oblique slots 249 are formed in both ends of cam
crank
241, 242 permitting the same part to be used as either 241 or 242 rather than
requiring
fabrication of different left hand and right hand parts. The obliqueness of
slot 249
permits a straight bar to be inserted with less tendency, when rotated, to
foul side sill
84 or 86 as the case may be. Although slot 249 is preferred, other types of
torque
input fitting, such as a bent arm (to act as a lever), a lateral pin of shaft,
a keyway, a
spline or splines, a hexagonal or square head to be engaged by a wrench or
socket, an
allen head and so on could be used. Slot 249 conveniently does not require the
use of
a special socket or key of a particular size.
A first radially extending member, in the nature of an M-shaped cam throw
portion 250 extends between inboard and outboard hinge portions 244 and 246,
and
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will be forced through an arcuate path when a sufficiently large torque is
applied
though the crank. In so moving, the flattened peaks of the M-shape, indicated
as 254,
255, act as cams that work to raise distal portion 239 of bridge plate
transition plate
230, (or 232), forcing plate 230 (or 232) to pivot, the proximal end of plate
230 being
held down by hinge tangs 234, 236 so that the tip, i.e., distal portion 239 of
plate 230
(Figures 6a, 6b, 6c) is lifted clear of bridge plate 150. Flattened peaks 254
and 255
(Figures 7a, 7b, 7c) are provided with bushings, or rollers 257, that bear
against the
underside of bridge plate transition plate 230 (or 232).
If bridge plate 150 is in an employed, i.e., extended, position when
transition
plate 230 is lifted, it may tend to want to droop downward since it is
cantilevered out
over end sill 122 without sufficient reaction force, or weight, at the
proximal end to
keep the distal end up. A downward droop may tend not to be advantageous when
pushing cars together to be coupled, since the distal tip would then have a
tendency to
jam into the end sill of the adjacent car. It is also not desirable to require
railroad
employees to have to hold the bridge plate tips up as railcars come together.
To that
end the middle portion of the M-shape, indicated as 258 has a retainer, in the
nature of
a protruding catch, pawl, tooth, stop or abutment 260, fabricated in the form
of a bent,
t-shaped tang 261 with arms welded to either side of portion 258 and the
tongue of
tang 261 extending above and beyond portion 258. When cam crank 241 is rotated
to
lift plate 230, abutment 260 is placed in a position to intercept the most
inboard edge
262 of sheet 152. When thus engaged, abutment 260 discourages bridge plate 150
from drooping as adjacent cars are brought together.
Further, cam crank 242 can be moved to a fully engaged position to lift
transition plate 232 whether or not a bridge plate is present. When the tip,
or distal,
portion 239 of plate 232 is thus lifted, the distal tip of a bridge plate 150
of an
adjoining car can then be introduced, as shown in Figures 8a and 8b. As the
tip of the
other bridge plate moves into position, it engages the M-shape of cam crank
242 and
pushes it backward (i.e., counterclockwise from the viewpoint of a person
standing
beside car unit 34 facing side sill 86 on the handle side of cam crank 242) to
a
disengaged position. As this happens, transition plate 232 falls down to
engage the
upper surface of the incoming bridge plate in an overlapping position. Once
the tip of
the other bridge plate is on shelf portion 134 (Figure 8d) it can be nudged
(if required)
3 S into position to permit pin 205 to be inserted.
The sequence of operation for uncoupling two rail road cars such as cars 21
and 22 to permit conversion from "drive-over" ends to a "ramp end" is as
follows:
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Remove the cross-pin from the lower slot of pin 205. Lift pin 205 and place on
deck
100. Support the distal tip of bridge plate 150 (can be manually lifted, or
alternatively, propped in place). Engage a pry bar or similar bar as a lever
in the
outboard oblique slot in cam crank 241, and apply a force to the bar to
generate a
torque to twist cam crank 241 counter-clockwise (as viewed facing the side
sill by a
person standing beside the car applying force to the lever). This causes the
distal edge
of transition plate 230 to lift, thereby disengaging plate 230 from bridge
plate 150.
Engage abutment 260 to edge 262 of bridge plate 150. (The distal tip of bridge
plate
150 can be released once abutment 260 is engaged). Engage a pry bar as a lever
in
the outboard oblique slot in cam crank 242 and twist in a clockwise direction
to lift
transition plate 232 to a position for receiving another plate. (This step can
either
precede or follow the step of lifting transition plate 230). Operate the
uncoupling rod
to unlock the coupler and close the angle cocks (standard steps for uncoupling
railcars
generally). Pull the rail road cars apart. Rotate (i.e., pivot) bridge plate
150
clockwise (as viewed from above) on pin 204 until toes 88 and 90 rest on shelf
portion 134 beneath the overhang of plate 232. Adjust as needed to permit pin
205 to
enter collar 200, and install pin 205 to secure the distal end of the bridge
plate in place
in the stored position. Lower plate 232 to engage, i.e., sit on, bridge plate
150.
To reverse the process: Unlock, and remove pin 205. Use a pry bar as a lever
in the outboard oblique bores (i.e., slot 249) of cam cranks 241, 242 to raise
intermediate transition bridge plates 230, 232, disengaging them from bridge
plate
150. Haul bridge plate 150 out of its storage position by rotating (i.e.,
pivoting) it
counter-clockwise about pin 204 to the extended position, with edge 262
restrained
under abutment 260. This is the position shown in Figure 8a. Advance the rail
cars
towards each other to cause the respective bridge plates 150 to be received
under
respective intermediate transition plates 232, each bridge plate advancing to
encounter
cam crank 242 of the opposing railcar, knocking it down as the couplers
connect. (See
Figures 8b, and 8c). Replace pins 205 of each respective car, nudging or
adjusting the
bridge plates as required, partially raising bridge plate 232 if necessary to
facilitate
this nudging, and locking pins 205 in place when seated satisfactorily, thus
securing
bridge plate 150. Lower plate 230 onto bridge plate 150. Re-establish the
coupling
between the two cars, including .brake lines. The train is again ready to be
moved
along the rail line.
Alternatively, following the sequence of Figures 8a, 8e, 8f and 8d, when
moving the rail road cars together, once the toe of bridge plate 150 (of, for
example,
car unit 34 of car 22) overhangs shelf portion 134 of the adjacent car (e.g.,
car unit 36
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of car 24), locomotive 38 can be stopped. Bridge plate 150 can be lowered to
lie on
the receiving portion of the adjacent car, namely shelf 134, by twisting cam
crank 242
to release the heel edge, edge 262, of bridge plate 150. The locomotive can
continue
to urge the cars together, with bridge plate 150 sliding across shelf 134 to
meet cam
crank 241. The procedure may then continue as before, with re-insertion of pin
205,
and so on.
In either sequence, the process includes the steps of positioning the
respective
bridge plates of the rail road cars in a length-wise orientation and advancing
the rail
road cars toward each other to cause their respective couplers to mate. The
step of
advancing includes the step of engaging an extended portion, the distal tip,
of each of
the bridge plates with a receiving member, shelf portion 134, of the other
rail car. The
step of positioning each of the bridge plates includes securing the distal tip
in a raised
attitude relative to the proximal portion, as described above. The step of
engaging
1 S includes a step of securing each the bridge plate to the other of the rail
road cars by re-
inserting hinge pin 205 to link slot 186 of each bridge plate with the socket
formed by
the respective collars, 200.
The step of advancing the cars together is preceded by the step of moving
(i.e.,
raising) transition plates 232 to the raised position to facilitate engagement
of bridge
plate 150 with the receiving member, namely shelf portion 134. The step of
engaging is
followed by the step of placing, (i. e., lowering) transition plate 232 to an
overlapping
position between the received distal tip of bridge plate 150 and vehicle
carrying deck 47.
The step of raising transition plate 232 includes the step of employing a
prop, namely
cam crank 241 to maintain transition plate 232 in the raised position. The
step of
engaging includes advancing the bridge plate to disengage the prop, thus
causing
transition plate 232 to move to the overlapping position.
On level track, the swinging of bridge plate 150 between length-wise and
cross-wise positions occurs in the plane of shelf portion 134, that plane
being a
horizontal plane, such that rail yard personnel do not need to raise (or
lower) the
bridge plate to (or from) a vertical, or nearly vertical, position as was
formerly
common. Further still, since the arrangement of bridge plate 150 can
accommodate
train motion, whether due to pitch, yaw, roll or uneven spring compression
between,
for example, car units 34 and 36, bridge plate 150 may remain in its extended,
bridging position spanning the gap between units 34 and 36 when rail road cars
22
and 24 are in motion, and does not need to be moved each time the train is
loaded or
unloaded. Bridge plate 150 may tend not to need to be moved to or from its
stowed
20793592.1
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position except when rail road cars 22 and 23 (or such others as may be joined
together) are split apart from their neighbours, or joined together again.
This may
occur only relatively infrequently to permit the train consist to be changed.
This may
tend to reduce the number of times rail yard personnel are required to handle
the
bridge plates, and may tend to reduce the length of time required for loading
and
unloading.
The process for changing bridge plate 150 from the length-wise position to the
cross-wise position is relatively simple: the rail car is established in an
uncoupled
IO position by uncoupling the rail road cars and moving them apart, thus
disengaging the
distal tip of bridge plate 150 from the adjacent car, and establishing bridge
plate 150
in the extended position. Pin 205 is removed, transition plate 230 is
disengaged from
bridge plate 150 by raising its distal portions clear of bridge plate 150.
Plate 232 is
also raised. Then bridge plate 150 is moved from the length-wise position to
the
1 S cross-wise position. As noted, the step of moving includes swinging bridge
plate 150
in the horizontal plane of portion 134 about the pivot mounting provided by
the
interaction of pin 204 in collar 200. This is followed by securing bridge
plate 150 in
place by reinserting pin 205 as a retainer, and by re-engaging transition
plates 230,
232, as by lowering them to the overlapping position. The step of disengaging
the
20 transition plate from the bridge plate includes the step of operating cam
cranks 241,
242 to lift the distal portions of transition plates 230, 232. The step of
operating the
cam cranks includes the step of turning them to bear against the transition
plates.
The process of converting and re-coupling cars can be followed by a series of
25 steps for unloading, and then loading (or re-loading) that include placing
ramps at the
rail road car ends, as described above and shown in Figures la - le. In the
loading
and unloading processes the hostler truck and the highway trailers will cross
bridge
plate 150 in its stored, or laterally transverse, position.
30 It may be noted that while telescoping bridge plates could possibly be
employed, it is preferred to use a monolithic bridge plate, such as bridge
plate 150.
That is, bridge plate 150 is a rigid beam. It does not have two beam portions
that slide
together. The pivot fitting at the proximal end anchored by pin 204, and the
combined pivot and slot fitting for engaging pin 205 have a relatively large
tolerance,
35 and do not bear either a shear load or a bending moment load when vehicles
traverse
bridge plate 150. Bridge plate 150 acts as a lintel, or beam, of sufficient
length to
span the gap between the ends of the two adjacent rail road cars when
motionless on
20793592.1
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straight track, the lintel being supported at either end by two shelves. As
such, it has
the advantage of comparative simplicity.
Figures lla and llb show the draft gear at the coupler end of rail car unit
34,
being representative of the coupler end draft gear of rail road cars 21, 22,
23, 24 and
25 more generally. Coupler pocket 62 houses a coupler indicated as 44. It is
mounted
to a coupler yoke 378, joined together by a pin 380. Yoke 378 houses a coupler
follower 382, a draft gear 384 held in place by a shim (or shims, as required)
386, a
wedge 388 and a filler block 390. Fore and aft draft gear stops 392, 394 are
welded
inside coupler pocket 62 to retain draft gear 384, and to transfer the
longitudinal buff
and draft loads through draft gear 384 and on to coupler 44. In the preferred
embodiment, coupler 44 is an AAR Type F70DE coupler, used in conjunction with
an
AAR Y45AE coupler yoke and an AAR Y47 pin. In the preferred embodiment, draft
gear 384 is a Mini-BuffGear. Mini-BuffGear are supplied by Miner Enterprises
Inc.,
supra, or by the Keystone Railway Equipment Company of 3420 Simpson Ferry
Road, Camp Hill, Pa. As taken together, this draft gear and coupler assembly
yields a
reduced slack, or low slack, short travel, coupling as compared to a Type E
coupler
with standard draft gear or an hydraulic EOCC device. As such it may tend to
reduce
overall train slack, and may tend to reduce the range of travel to be
accommodated by
bridge plates 150. In addition to mounting the Mini-BuffGear directly to the
draft
pocket, that is, coupler pocket 62, and hence to the structure of the rail car
body of car
unit 34, the construction described and illustrated is free of other long
travel draft
gear, sliding sills and EOCC devices, and the fittings associated with them.
Mini-BuffGear has between 5/8 and 3/4 of an inch travel in buff at a
compressive force of 700,000 Lbs. Other types of buff gear can be used that
will give
an official rating travel of less than 2 1/2 inches, or if not rated, then a
travel of less
than 2 1/2 inches under 500,000 Lbs. buff load. For example, while Mini-
BuffGear is
preferred, other draft gear is available having a travel of less than 1 3~4
inches at
400,000 Lbs. buff load. One type has about 1.6 inches of travel at 400,000
Lbs. buff
load. It is even more advantageous for the travel to be less than 1.5 inches
at 700,000
Lbs. buff load and, as in the embodiment of Figures 12a and 12b, preferred
that the
travel be at least as small as 1" inches or less at 700,000 Lbs. buff load.
Similarly, while the AAR Type F70DE coupler is preferred, other types of
coupler having less than the 25/32" (that is, less than about 3/4") nominal
slack of an
AAR Type E coupler generally or the 20/32" slack of an AAR ESOARE coupler. In
particular, in alternative embodiments with appropriate housing changes where
20793592.1
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required, AAR Type F79DE and Type F73BE, with or without top or bottom
shelves;
AAR Type CS; or AAR Type H couplers can be used to obtain reduced slack
relative
to AAR Type E couplers.
Other than brake and minor fittings, the basic structure of center sill, cross-
bearer and decking structure of intermediate car unit 30 is substantially the
same as
car units 26 and 34. Car unit 26, shown in Figures 9a (isometric), 9b (top),
9c (side
view) and 9d (underframe) differs from car unit 34 primarily in having a
female set of
side bearing arms, like those of car unit 30 adjacent to car unit 34. The
hitch
arrangement will be different, with the hitches on all of car units 26, 30 and
34 being
arranged such that trailers mounted thereon will have their forward ends (i.e,
the end
with the king pin) facing toward end portion 64 of car unit 34. Car units 26,
30 and
34 may also vary in their brake arrangements, and other fittings, but share
the same
basic structural features. However, as intermediate unit 30, shown in Figures
l0a
1 S (isometric), lOb (top), lOc (side view) and lOd (underframe) has no
coupler end, its
construction can be conceptualized as having the articulation connection end
of car
unit 34 taken from a mid span section, with a set of male side bearing arms,
and the
articulation connection end of car unit 26 with female side bearing arms, also
taken
from mid-span section, and joining them together in one car, with the pair of
female
side bearing arms facing car unit 34 and the pair of male side bearing arms
facing car
unit 30.
Various embodiments of the invention have now been described in detail. Since
changes in and or additions to the above-described best mode may be made
without
departing from the nature, spirit or scope of the invention, the invention is
not to be
limited to those details.
20793592.1
