Note: Descriptions are shown in the official language in which they were submitted.
` - 21 722(30
CRANE TROLLEY HAVING PIVOTAL ARMS
Field of the Invention
This invention relates to a trolley for use in large cranes
and, in particular, to a trolley suspended from the overhead load
carrying beam of a gantry crane.
Background of the Invention
Cranes of the larger sizes typically present shipping
problems from the facility at which they are fabricated to their
installation destination. The large dimensions of these cranes
require that they be shipped in a number of disassembled separate
pieces and components and be assembled at their destination. In
particular, gantry cranes of the portal type in which the loads
lifted by the crane are moved between the legs of the crane are
of a very large size which makes them difficult to ship and
assemble. These cranes thus require a design which enables
shipping of the load carrying beam, the trolley and the legs in
several sections and assembly (or reassembly) and connecting of
the major sections at the time of erection of the crane.
A further problem which arises where the crane or components
of it are assembled at the factory and then disassembled for
shipment is that, at the time of reassembling of the crane at the
operation site, there are a large number of interfitting parts
which must be marked at the factory to enable reassembling at the
operation site. The markings of parts is quite time-consuming.
However, it is particularly necessary where there are parts which
are similar, but not identical, and therefore not interchangeable
~ 2~ 722D~
~t the time of reassembling at the operation site.
Although the load carrying beam and the legs of large portal
cranes present the greatest problems for shipment due to their
size, the trolleys of such large cranes are frequently also of
a size which makes it difficult to efficiently transport them to
the operation location. The applicant's invention is an
improvement in a large crane trolley which minimizes the shipment
problems due to the large size of the trolley and assists with
the factory assembly and mounting of the trolley onto the load
carrying beam at the operating site.
Summary of the Invention
It is a general object of this invention to provide a
trolley suspended from the overhead load carrying beam of a crane
with depending arms which can be pivoted to decrease the size of
the trolley during shipment and pivoted subsequent to shipment
to a position at which the arms support the trolley when mounted
on the crane. It is a further object of the invention to provide
the trolley with supporting arms which can be pivoted to assist
with affixation of equipment on the trolley and to assist with
mounting of the trolley on the crane beam.
The invention is carried out by providing, in a crane having
an overhead beam and a pair of parallel rails, a trolley platform
positioned below the beam for carrying a crane hoist, a plurality
of trolley drive means each having a wheel rotatable on one of
the rails for supporting the drive and the trolley on the rails,
and a plurality of arms each having an upper end affixed to and
supporting a drive means and a lower end pivotally connected to
21 7`22(~0
~che platform. Each arm has a position pivotal towards the
platform for decreasing the width of the trolley during shipment
and a second position pivotal away fro~ the platform for locating
the drive means at the support positions on the rails. The drive
means may be mounted on the arms such that the drive means
projects laterally away from the platform. The arms of the
trolley consequently are pivotal inward towards the platform such
that the drive means project away from the platform laterally no
further than the width of the platform.
The arms of the trolley may also have a further position
extending laterally of the platform at which position they become
relatively accessible for the affixing of the drive means to the
arms.
Subsequent to shipment of the trolley to the crane operating
site with the arms pivoted inward toward the platform, the
trolley may be mounted onto the rails of the load carrying beam
of the crane by moving the arms outward away from the platform
to a position at which the wheels of the drive means will engage
the crane rails when the trolley is rolled onto the rails at an
end of the load carrying beam. Alternatively, the trolley may
be mounted onto the crane by pivoting the arm to a position such
that the wheels on the arms are outward and adjacent to the rail
with which they will be engaged and also slightly above such
wheel and then pivoting each arm inward and lowering the trolley
downward to engage each wheel with a rail.
- 21 72200
- Brief DescriPtion of the Drawinqs
Further objects and advantages of the invention will appear
when taken in conjunction with the accompanying drawings, in
which:
FIG. 1 is a perspective view of a portal crane having an
overhead load carrying beam on which a trolley according to the
invention may be mounted;
FIG. 2 is an end view of the crane and trolley, with
portions removed, illustrated in FIG. l;
FIG. 3 is an end view of the trolley according to the
invention illustrating the support arms of the trolley pivoted
downward to a position near a floor during the fabrication of the
trolley;
FIG. 4 is a perspective view of the trolley shown in FIGS.
1-3 with the support arms folded in toward each other on the
flatbed of a truck during transporting of the trolley;
FIG. S is a side view of the trolley shown in FIGS. 1-4
illustrating the mounting of the trolley onto the beam of a
portal crane;
FIG. 6A is an end view of the load carrying beam and trolley
as shown in FIG. 1 with the beam positioned near ground level
during assembly of the crane and trolley; and
FIG. 6B is an end view similar to that shown in FIG. 6A with
the support arms of the trolley engaging the rails of the load
carrying beam.
21 72200
- Detailed Description of the Invention
Referring to FIGS. 1 and 2 of the drawing, a crane of the
portal type with which the invention operates is illustrated as
having an overhead load carrying beam 2 disposed generally
horizontally and overlying two spaced apart legs 4 and 6 affixed
to the beam 2. Rails 8 and 10 run through a storage area for
material which is to be lifted and transported into and out of
the storage area by the crane. The leg 4 includes elongated
members 12 and 14 respectively and the leg 6 includes elongated
members 13 and 15. The members 12 and 13 are connected to lower
base ends 16 and the members 14 and 15 are connected to lower
base ends 18. The base ends 16 and 18 respectively have a pair
of spaced apart wheel assemblies 20 and 22. The wheel assemblies
20 and 22 on leg 4 and the wheel assemblies 20 and 22 on leg 6
respectively engage and ride on the tracks 8 and 10, thus
permitting the crane to travel along the tracks 8 and 10 through
the material storage area. Drive motors 24 are mounted on the
wheel assemblies 20 of lower bases 16 and lower base 18 for
moving the crane along the tracks 8 and 10.
The overhead beam 2 includes a pair of chords 27 and 29 on
which parallel rails 28 and 30 are respectively mounted and on
which a trolley 40 is supported for travel along the length of
the beam 2. The trolley 40 includes a platform 42 positioned
below the beam 2 and the rails 28 and 30, and further includes
arms 32, 34, 36 and 38 which extend downward from adjacent the
rails 28 and 30, as shown in FIGS. 1 and 2, and are pivotally
connected to the platform 42. At least one wheel 44 is mounted
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~n the upper end 45 of each of the arms 32, 34, 36 and 38 and is
engagable with one of the rails 28 or 30 to permit the trolley
40 to travel along the length of the beam 2 on the rails above
the storage area.
Referring further to FIGS. 1 and 2, a lifting beam 80 is
suspended from the trolley 40 by a reeving apparatus 82 which is
affixed to the platform 42 of the trolley, to a rotatable drum
means 84 mounted on the trolley platform 42, and to the lifting
beam 80. The drum means 84 includes a winding drum and drum
drive motor. A load carrying means such as a grapple 86 is
rotatably connected to the lifting beam 80 and to the winding
drum 84 for raising and lowering, and grasping and releasing
material to be carried. The operation of the grapple 86, the
winding drum 84, the movement of the trolley 40, and the movement
of the crane on the tracks 8 and 10 is controlled by an operator
in a cab 52 to lift, transport and set down material within the
travel range of the crane and the trolley, in a manner well known
in the art.
With reference generally to the drawings, the trolley 40,
in addition to the platform 42, arms 32, 34, 36, 38 and wheels
44, includes a trolley drive means 46 mounted on the upper end
45 of one or more of each of the arms 32, 34, 36 and 38. Each
of the drive means 46 includes a motor 48 and gear box 50
connected to and driving one of the wheels 44. Each of the drive
means 46 is mounted on a bracket 52 on the outward side, that is,
the side of the arm away from the platform 42 and has an outward
end 54 projecting laterally away from the platform 42.
The arms 32, 34, 36 and 38 are respectively pivotally
21 722GO
~ounted at their lower ends 58 on ears 60, 62, 64 and 66 affixed
to and extending from the side edges 68 or 70 of the platform 42.
Pins 71 extend through each arm and ear, as shown in FIGS. 3, 4,
6A and 6B. The arms 32, 36 and the arms 34, 38 are respectively
connected by reinforcing members 72 and 74. In addition, when
the arms 32, 34, 36 and 38 are in their upright position as shown
in FIGS. 1, 2, 5 and 6B, the arms 32, 34 and the arms 36, 38 are
respectively connected by a reinforcing member 90.
As previously mentioned, the platform 42 has projecting ears
60, 62, 64 and 66 and opposite side edges 68 and 70. The trolley
40 has a transverse width a as best shown in FIG. 6B, which is
transverse to the direction of travel of the trolley on the rails
28 and 30. This is the operating width or position of the
trolley and includes the widths of the platform 42, ears 60, 62,
64 and 66, and drive means 46 out to the end projections 54.
The arms 32, 34, 36 and 38 are pivotal on the ears 60, 62,
64 and 66 of the platform 42 to various positions for purposes
of assembly of the trolley 40 at the factory, transporting the
trolley 40 to a customer's operating site, and mounting of the
trolley onto the overhead carrying beam 2. Depending on the
assembly method used, the arms may be pivoted downward to an
assembly position, as shown in FIG. 3, near the floor of a
fabricating facility to permit easy access to the upper ends of
the arms for mounting the drive means 46.
Where the trolley 40 is of a particularly large size for a
very large portal crane, difficulties in shipment due to the
large size of the trolley can be alleviated due to the pivoting
of the arms on ears 60, 62, 64 and 66 of the platform 42. As
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own in FIG. 4, in which the trolley is shown loaded for
shipment on a truck bed 88, the arms 32, 34, 36 and 38 have a
position in which they have been pivoted laterally inward toward
the platform 42 with the arms 32 and 34 positioned toward each
other and the arms 36 and 38 positioned toward each other. In
these positions of the arms, the width of the trolley can be
minimized to a transverse width or position b not greater than
the combined width of the platform 42 and the pairs of ears 64,
66 or 60, 62 so that components of the trolley mounted on the
arms outward of the platform and ears will not increase the width
of the trolley during shipment. The trolley is shown in FIG. 4
with the arms pivoted inward a distance such that the outward
projecting ends 54 of the drive means 46 mounted on the arms
extend no farther outward than the transverse width b of the
trolley. The arms could, of course, be pivoted further inward
if components of the trolley other than the drive means are
mounted on the arms projecting outward from the trolley.
Following the transporting of the trolley to the customer's
operating site, it must be mounted onto the rails 28 and 30 of
the overhead beam 2. As part of the erection of the entire
crane, the beam 2 is initially assembled adjacent ground level
and later elevated on the legs 4 and 6 to an erect position
substantially as shown in FIG. 1. However, while the beam 2 is
supported adjacent ground level 92, as shown in FIG. 5, the
trolley may be mounted onto the beam 2. In FIG. 5, the arms 32,
34, 36 and 38 of the trolley are in an upright position at which
the wheels 44 can be rolled onto the rails 28 and 30 to thereby
mount the trolley on the beam.
2l 72~GO
- At the time of the mounting of the trolley onto the beam,
the reinforcing members 90 and 72, 74 may also be connected to
the arms 32, 34, 36 and 38. Subsequently, when the beam 2 is
raised to its operating position on the legs 4 and 6, the trolley
will be in a position on the rails 28 and 30 to function as
previously described.
An alternative method of mounting the trolley 40 onto the
beam 2 is illustrated in FIGS. 6A and 6B. In this mounting
method, the trolley is first supported with the wheels 44 on the
upper ends 56 of the arms 32, 34, 36 and 38 slightly above the
rails 28 and 30, and pivoted slightly outward of the rails 28 and
30, as shown in FIG. 6A. The arms are then pivoted inward toward
the platform 42 so that the wheels are directly above the rails
28 and 30, as shown in phantom lines in Fig. 6B. The trolley is
then lowered so that the wheels 44 move downward into engagement
with the rails 28 and 30. The beam 2 with the trolley 40 may
then be elevated to its operating position as shown in FIGS. 1
and 2.
Due to the assembly of the arms 32, 34, 36 and 38 to the
platform 42 at the factory, and the ability of the arms to pivot
to decrease the width of the trolley to assist with its shipment,
and to pivot outward to enable mounting the trolley to an
operating position, there is no need to mark various parts at the
factory and then match various similar parts when assembling in
the field. Thus differences in measurements for the positioning
of openings for bearings, shafts or pins, which require close
matching of parts when assembling, are not a problem when
assembling in the field. Also, slight changes in shape or
21 72200
~sition of parts due to warping during cooling following welding
also are not a problem. Although positioning differences between
parts due to these fabricating problems may sometimes be small,
the resulting increase in wear can be significant and require
relatively early maintenance and replacement.
It will be understood that the foregoing description of the
present invention is for purposes of illustration only and that
the invention is susceptible to a number of modifications or
changes, none of which entail any departure from the spirit and
scope of the present invention as defined in the hereto appended
claims. -::
