Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1055989
This invention relates to lifting apparatus for
placing an elongated cover on an elongated open top rail car
and removing a cover therefrom.
In the railway transportion of material such as ore
concentrates in open top rail cars, it is desirable to protect
the material against loss or damage by providing the cars with
covers. In particular, it is essential that lead ore
concentrates be protected against atmospheric moisture to avoid
exceeding the Transportable Moisture Limit as de~ined in the
Code of Safe Practice for Bulk Cargoes. Open top rail cars in
which such material is transported are large, for example,
about 50 feet long and about 10 feet wide. Multiple section
covers, although easier to handle in a section-by-section
manner, are not generally satisfactory and one piece covers
are preferred. The connection of the separate sections of a
multiple section cover to provide moisture-tight joints is a
time consuming operation. On the other hand, the size of a
one-piece cover ma~es placement and removal by conventional
equipment difficult. For example, if a conventional overhead
crane is used, accurate positioning of such a crane over a
rail car cover is difficult, as also is the movement of a
cover from one place to another. One piece covers frequently
become broken with such manoeuvring, particularly if a strong
wind is blowing.
It is therefore an object of the invention to
provide lifting apparatus which enables one piece covers to be
readily placed on and removed from elongated open top rail cars.
` According to the invention, lifting apparatus for
placing an elongated cover on an elongated open top rail car
and removing a cover therefrom comprises a carriage mountable
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on a movable vehicle operable to raise and lower the carriage,
a shift frame slidably mounted on tle carriage for transverse
sliding movcment relative thereto, means for effecting said
transverse sliding movement of the shift frame relative to the
carriage, and an elongated lift frame suspended from the shift
frame and extending transversely thereof, said lift frame having
means for engaging an elongated rail car cover to enable the
cover to be raised and lowered by raising and lowering respec-
tively of the carriage by the movable vehicle.
With the lifting apparatus of the present invention,
the lift frame can be easily and accurately aligned with a
cover on the rail car or at a storage position by combination
of movement of the vehicle and movement of the shift frame
relative to the carriage. Similarly, the cover carried by
the lift frame can be easily and accurately aligned with the
open top of a rail car. Furtner, the lifting apparatus is
relatively inexpensive, and is preferably constructed so that
a forlc-lift truck can be used as the movable vehicle, with
the carriage of the lifting apparatus being mountable on
the forks of tne fork-lift truck. Also, the lifting apparatus
is preferably constructed so that, during handling of the cover
by the apparatus, movement of the cover relative to movement
of the lifting apparatus is restrained. Consequently, the risk
of damage by strong wind or movement of the vehicle carrying the
cover over uneven ground is small.
The elongated lift frame may be suspended from the
shift frame by flexible suspension elements permitting a
limited amount of relative movement between the lift frame
and the shift frame. The flexible suspension elements are
preferably short so that the limited amount of movem2nt of
the lift frame relative to the shift frame is only sufficient to
perrnit final alignment of the lift frame with tlle car cover after
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initial positioning of the movable vehicle as hereinaEter
explained.
~ dvantageously, the lift frarle has a set of cam surfaces
engageable with a set of cam surfaces on the rail car cover to
guide the lift frame into an alignment position on the cover from
a predetermined position close thereto, any required limited
amount of movement of the lift frame relative to the shift frame
being permitted by the flexible suspension elements. The means
for engaging the cover is properly positioned with respect to
the cover by movement of said sets of cam surfaces into engagement
position during lowering of the lift frame onto the cover. The
cam surfaces of the cover may be portions of stacking pads which
permit stacking of the covers one upon another in spaced relation-
sllip witn the stacking pads of each cover engaging those of an
adjacent cover in a stack. The r.leans for engaging the cover
may comprise spaced pins slidably mounted on the lift frame Eor
engagement in lifting loops on the cover.
Where the carriage is mountable on a fork-lift truck,
the carriage may include a pair of spaced parallel open-ended
beams into which the forks of the fork-lift truck can be
inserted for raising and lowering the carriage with raising and
lowering respectively of the forks of the fork-lift truck. The
shift frame may include a main beam slidably mounted in bearings
carried by the carriage beams.
The means for effecting transverse sliding movement
of the shift frame relative to the carriage may include a fluid
pressure operated cylinder assembly connected to the shift frame
and to the carriage. Similarly, the means mentioned above for
engaging the cover may also include fluid pressure operated
cylinder assemblies carried by the lift frame for effecting
movement of the spaced pins.
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One embodiment of the invention will now be described
by way of example with reference to the accompanying drawings
in which:
Figure 1 is a perspective view of lifting apparatus
mounted on a fork-lift truck and positioned
for removin~ a cover from a rail car:
Figure 2 is a front view of the shift frame and lift
frame of t}-e lifting apparatus with some
parts being omitted for clarity;
Figure 3 is a side view of the lift frame sho~ing one
of its cross beams aligned with the stacking
pads of a cover on a rail car;
Figure 4 is a plan view of the shift frame and carriage
of the lifting apparatus; and
Figure S is a plan view of the lift frame of the
lifting apparatus.
Referring to the drawings, lifting apparatus 10 for
lifting covers of open top rail cars includes a carriage 12
having a pair of spaced, parallel, hollow beams 24 connected
adjacent opposite ends by cross members 20, 22. The beams 24
are spaced apart a distance equal to the spacing between the
forks of a conventional lift truck, and are open-ended at the
rear so that the lift truck forks can be inserted therein. The
cross member 20, which is adjacent the open ends of the beams
24, has legs 26 at opposite ends to provide support for the
rear end of the carriage 12 of the apparatus when it is not in
use.
Two sleeve bearings 28 are mounted on the heams 24 near
the front end of carriage 12 for supporting the main beam 30 of
a shift frame 14, the main beam 30 being slidably mounted in
the bearings 28.
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A central cross beam 36 is secured to the main beam 30
at its mid-point and extends horizontally on both sides of the
main beam 30. ~ hydraulic cylinder 32 is mounted on one beam 24
of carriage 12, and a piston rod 34 extendinq from cylinder 32 is
connected to tlle central cross beam 36 of the shift frame 16 -to
provide controlled lateral movement of the shift frame 14
relative to the carriage 12. At each end of the main beam 30 of
the shift frame 16, there is a cross beam 38 which also extends
horizontally on both sides of the main beam 30. The central
cross beam 36 is slightly longer than the end cross beams 38, as
can be seen from Figure 4. Lugs 40 on the under side of each
end of cross beam 36, and lugs 42 on the under side of each end
of each cross beam 38 are provided for the removable attachment
of six chains from which lift frame 16 is suspended, as will be
described in more detail later.
Lift frame 16 has a main beam 44, a centrally located
cross beam 46 which extends on each side of the main beam 44,
and a cross beam 48 at each end which extends on each side of
the main beam 44. As can be seen from Figure 5, end cross beams
48 are considerably longer tnan centre cross beam 46. From
Figures 4 and 5, it can be seen that centre cross beam 36 of
shift frame 14 is equal in length to centre cross beam 46 of
lift frame 16.
Lugs 50 and 52 for chain support of lift frame 16
below shift frame 14 are respecti~ely attached near the ends
on top of cross beam 46 and on top of main beam 44 on each side
of cross beam 46, Six short chains, represented in part by
chains 54 in Figure 2, connect lift frame lugs 50 to shift
frame lugs 40, and lift frame lugs 52 to shift frame lugs 42
to suspend lift frame 16 a few inches below shift frame 14. The
chains connecting two lugs 42 to a single lug 52 are inclined
to each other at an angle about 45 to inhibit lateral
~osssss
movement of the lift frame 16 relative to the shift frame 14.
This suspension permits minor horizontal adjustments of the
position of the lift frame 16 wit}lOut moving the fork lift truck,
compensates for uneven ground by providing for minor vertical
misalignment and, because of the arrangement of the chains,
permits only limited sway during movement of the for}-lift truck.
On the underside of main beam 44 of the lift frame 16,
near each end, are means 56 for engaging spaced lifting loops 58
attached to the top of an arched rail car cover 60. Each
engaging means 56 includes a hydraulic cylinder 62 operable to
move a pin 64 across a gap between spaced sleeves 66,68 secured
to the main beam 44, the pin 64 being slidable in the sleeves
66,68. The hydraulic cylinders 62, as well as the previously
mentioned hydraulic cylinder 32, are readily connectable by
hydraulic connections to a source of hydraulic pressure and
appropriate controls on the fork-lift truck so that the
operation of the hydraulic cylinders 62 and the hydraulic cylinder
32 can be controlled by the operator of the fork-lift truck.
In order to make the lift frame 16 more rigid, a rod
70 passes from one end of the main beam 44 to the other over
pillars 74 mounted on the main beam 44, opposite ends of the rod
70 being attached to lugs 72 at opposite ends of the main beam 44.
Near each end of each outer cross beam 48, supports 76
extend downwardly and carry horizontal plates 78 at their lower
ends. A stacking pad engaging cup 80 is bolted to the underside
of each plate 78. Each cup 80 has a cam surface in the form of a
concave recess 82 which matches a cam surface in the form of a
convex face portion 84 of one of four stacking pads 36 mounted on
the upper side of car covers 60. mhese cam surfaces are prefer-
ably spherically contoured. Each of the four cups 80 on lift
frame 16 is adjustably mounted on the respective plate 78 so
that the set of cups 80 is aligned to give simultaneous
engagement with the four stacking pads 86. Four vertical posts
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88, one at each end of each outer cross beam 48, are sufficiently
long to support the lift frame 16 on the ground without cups 80
contacting the ground.
As shown in Figure 3, rail car cover 60 has flanges 92
which rest on the top of car side walls 9g. Flanges 92 are
provided with means to secure the cover 60 to the car side walls
94, for example, slots (not shown) through which the heads of
spring-loaded bolts mounted on the rail car side wall may pass
before being turned at right angles to a locking position. Each
cover 60 is also provided with a set of stacking pa~s 9g attached
to the underside of the cover and aligned with the upper stacking
pads 86 to provide stable support for a plurality of covers in a
stack. Figure 3 also shows reinforcement ribbing 100 which
extends transversely across each cover 60 in line Witil each pair
of stacking pads g6 to give tne cover 60 greater stability during
handling.
When not in use, lift frame 16 of the lifting apparatus
is supported on the ground by vertical posts 8~ with the front
end of carriage 12 resting on the main beam 44 of the lift
frame 16 and the rear end of carriage 12 being supported by legs
26. To remove a cover from a rail car, a fork lift truc} is
manoeuvered to guide the forks 25 of the truck into carriage
beams 24, as indicated in Figure 2. The forks of the lift-tru_k
are then raised to lift carriage 12 and shift frame 14, first
extending the chains 54 and then raising the liEt frame lG off
the ground. The lift truck forks are raised to a height
sufficient to enable the lift frame 16 to clear the top of the
cover 60 on the rail car. The lift truc}; operator then guides
the lift truck visually to a position near the centre of the
rail car, with the lift frame 16 suspended over the car cover 6C
and with pad-engaging cups 80 approximately positioned
above corresponding stacking pads 86 on the cover 60. If the
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cam surfaces 82 and 84 are not aligned to provide easy engagement
on lowering of the lift frame, he then activates hydraulic
cylinder 32 to move shift frame 14 to tne right or to the left of
the fork-lif~ truck to improve longitudinal alignment, relativ~
to the rail car, of the pad-engaging cups 80 with the stacking
pads 86. At the same time, lateral alignment of the cups relative
to the car can be improved by moving the lift truck bac]cwards or
forwards. I~hen the lift frame is in this predetermined position
selected by operator judgment for cam engagement, the operator
lowers the for]s of the lift truck to permit cam surfaces 82 to
move on cam surfaces 84 to bring pad engaging cups 80 onto the
stacking pads 86.
Limited freedom of movement of the lift frame 16
provided by the chain suspension will permit the lift frame 16 to
move a small distance either longitudinally or laterally relative
to the rail car to correct minor alignment errors, without move-
ment of the remainder of the lifting apparatus. Such movement,
as the lift frame is lowered, enables pad engaging cups 80 to
seat properly on the stacking pads 36 with the mutually engaging
surfaces of the pad engaging cups 80 and the stacking pads 86
acting as cam surfaces to guide the lift frame 16 into tlle
required position relative to the cover 60. Cups 30 and face
portions 34 are preferably spherically contoured.
The covers 60 of open top rail cars are relatively
large, for example, about 50 feet long and 10 fee~ wide. It is
consequently difficult for the lift truc~ operator to correctly
position the fork lift truck on the first attempt so that the
pad-engaging cups 80 are within the one or two inches of align-
ment with the stacking pads 36 on the cover needed to get mating
engagement on 1O~.7ering the lift frame. With the lifting
apparatus of the present invention, the lift truck operator can
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~ asily reduce longitudinal misalignmen-t of up to one foot to a
distance within one or two inches of alignment, i.e. move the
lift frame to the predetermined position, after a single approach
to the side of the car by activating hydraulic cylinder 32.
Lateral misalignment, across the width of the car, is easily
taken care of by moving the lift truck forwardly or rearwardly.
Trial and error location of the truck at the centre of -the car,
by backing the truck and approaching in new positions Witll
resulting requirement for lateral realignrn~-~nt with each adjustment
of longitudinal alignment, is avoided. ~ny small remaining mis-
alignments after movement of the shift frame and simple advancing
or retreating of the truck on one line are easily taken care of
by the movement allowed by the stabilized suspension by short
chains 54 of lif-t frame 16 Erom shift frame 14. Chains which are
only a few inches long permit cups 80 to move horizontally from
the predetermined position within the one or two inch range of
stacking pad surfaces to alignment of cam surfaces which assures
mating engagement as the apparatus is lowered to place the weight
of the lift frame on the stac]cing pads.
During the previously described operation, the forks
of the fork lift truck are lowered only to such an extent that
the chains 54 slacken and the cover 60 supports the weight of
li.ft frame 16. The truck forks are not lowered to an extent that
would impose the weight of carriage 12 and shift frame 14 on lift
frame 16 and thence on the cover 60. The short chain suspension
of the lift frame 14 also provides operating leeway that permits
rapi~ placement of the lift frame 16 without damaging the cover
60. This chain suspension also compensates for uneven ground
conditions. For example, if because of tilting of the fork lift
truck relating to the rail car, the four stacking pads 86 are not
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contacted simultaneously as the lifting apparatus is lowered,
excessive loading will not be imposed on those pads 86 first
contacted.
Seating of the pad-engaging cups 80 on the cover
stacking pads 86 results in cover lifting loops 53 being
positioned between respective sleeves 66,68 on the lift frame
16. The operator then activates hydraulic cylinders 62 to move
lifting pins 64 from withdrawn positions into closure positions
passing through lifting loops 58 and entering sleeves 68. The
forks of the for]c lift truck are then raised to raise the
lifting apparatus thereby lifting the cover 60 from the rail car.
The for]c lift truc]c is then moved, with the cover 60, to a
convenient place, for example a stack of covers. After proper
positioning of the lift truck and actuation of the hydraulic
cylinder 32, if necessary, the lifting apparatus is lowered
until the lower stacking pads 98 on the cover 60 engage the
stacking pads 36 of the uppermost cover of the stack with the
covers in spaced relation to one another. I-lydraulic cylinders
62 are then actuated to withdraw the pins 64 from the lifting
loops 58.
When placing a cover 60 on a rail car, the operations
desired above are essentially reversed. A cover 60 is removed
from a stack in much the same manner as it was lifted from a
rail car,.and transported to a position above a rail car with
cover flanges 92 aligned with the car side walls 94. If
required, the operator makes lateral and longitudinal adjustments
as before except that, instead of bringing pad engaging cups 8G
into close alignment with stacking pads 86, the cover flanges 92
are brought into close alignment with the car side walls 94 to
permit engagement of closure bolts, for example, the previously
mentioned spring-loaded bolts, witn the cover flange slots.
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Because of the shortness of the chains 54 by which the
lift frame 16 is suspended from the shift frame 14, a cover 60
carried by the lift frame 16 cannot move relative to the fork
lift truck by an excessive amount. This reduces the risk of
damage to the cover 60 when the fork lift truck traverses rough
ground, for example rail track crossings, when moving the cover
60 from one place to another. It also reduces the risk of damage
to the cover 60 in a strong wind, since the wind cannot move the
cover 60 an unduly large amount while the cover 60 is carried by
the fork lift truck.
The lifting apparatus may also be provided with chains
and hooks to handle covers that do not have stacking pads which
mate with the pad-engaging cups 80 of the apparatus. These
chains may be attached at one end to lugs 90 on vertical corner
posts 88, with hooks being provided on the other ends for
anchoring to cover flanges. This arrangement is more convenient
than bringing in separate equipment when mixed style covers are
used in a single train. When these auxiliary chains and hooks
are not in use, it is convenient to drop these chains into the
hollow posts 88 and hang the hooks onto the upper ends of the
posts.
Also, if desired, a safety chain may be used to secure
the carriage 12 to the fork frame of the fork lift truck to
prevent the carriage 12 from slipping off the truck forks during
travel of the lift truck.
The advantages of the invention are clearly apparent
from the foregoing description of the preferred embodiment of
the invention. Other embodiments of the invention will be readily
apparent to one skilled in the art, the scope of the invention
being defined in the appended claims.
