Note: Descriptions are shown in the official language in which they were submitted.
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Support Assembly For Telescopic Conveyor System
The present invention relates to telescopic conveyor
systems, and in particular to support assemblies for
telescopic conveyor systems.
Telescopic conveyor systems are commonly used to
transport materials from one location to another
location. Typically, telescopic conveyor systems have a
frame which includes an elongate extendable frame mounted
for reciprocal movement on an elongate base frame.
Reciprocal movement of the extendable frame is usually
facilitated by a number of rollers which are mounted
directly on either the base frame or the extendable frame
and which travel along guide tracks. Examples of
extendable conveyor systems can be seen in U.S. patent
No. 3, 378, 125 issued April 16, 1968 to Fogg, U.S.
patent No. 3, 825, 107 issued July 23, 1974 to Cary et
al., and U.S. patent No. 5, 351, 809 issued Oct. 4, 1994
to Gilmore et al.
In recent years, mobile telescopic conveyor belts
have seen use in very heavy industries such as the
aggregate industry where mobile conveyors are used to
construct non-segregated stock piles of aggregate
materials. Telescopic conveyor belts used in the
aggregate industry are generally larger than those
described in the above mentioned patents, and have an
elongate base frame with a rectangular cross-section
which telescopically receives an elongate extendable
section having a smaller rectangular cross-section. By
way of example, the Thor Aggregate Equipment Division of
Thor Steel And Welding Ltd. of Mississauga, Ontario,
Canada produces and sells a telescopic conveyor system
for use in the aggregate industry known as a Telescopic
Portable Radial Stacker which, in one version, has a
retracted length of approximately 82.5 feet and an
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extended length of approximately 136 feet. In order to
adequately support the extendable frame, a number of
parallel, spaced support rollers are typically located at
the bottom side of the outward end of the base frame for
engaging the underside of the extendable frame, and a
number of parallel, spaced support rollers are located at
the top side of the base frame, some distance from the
outward end of the base frame, for engaging the top-side
of the extendable frame. In the past, these support
rollers have all been mounted on the base frame
independent of each other. Given the weight and size of
the extendable frame, and the weight of the aggregate
load it is used to transport, the extendable frame will
typically deflect to a certain degree of curvature along
its longitudinal axis when extended. The degree of
curvature will vary depending on, among other things, the
size of the conveyor system, the load carried, and the
extent that the extendable frame is actually extended at
any given time. As a result of this curvature, it has
been difficult to provide adjacent support rollers which
each bear a proportionate share of the weight of the
extendable frame. For example, when the extendable frame
is in its fully extended position, its curvature could
result in the support roller located closest to the
outward end of the base frame bearing substantially the
entire weight of the extendable frame while an adjacent
support roller was subjected to a disproportionately
lighter load. As a result disproportionate stresses are
concentrated on one support roller, and on the location
of the extendable frame that is engaged by the support
roller. Such a configuration requires that stronger and
more materials be used in the construction of the
conveyor frame to compensate for these disproportionate
stresses, and additionally may reduce the lifespan of the
support rollers.
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It is therefore desirable to provide a support
assembly for a telescopic frame which provides for a
proportional distribution of weight across a number of
adjacent support rollers regardless of the curvature of
the extendable frame. It is also desirable to provide a
telescopic conveyor belt system which has such a support
assembly.
According to one aspect of the invention there is
provided a support assembly for a telescopic frame having
an elongate base frame and an elongate extendable frame
reciprocally movable in a longitudinal direction along
the base frame, the support assembly being connectable to
the base frame for supporting at least a portion of said
extendable frame. The support assembly includes a pivot
plate device connected to the base frame to pivot about a
primary pivot axis that is substantially transverse to
the longitudinal axes of the base frame and the
extendable frame, and first and second bearing plates
mounted on the pivot plate device to pivot about a first
pivot axis and a second pivot axis respectively. The
first pivot axis and the second pivot axis are located on
opposite sides of the primary pivot axis such that the
pivot plate device functions as a first class lever.
The support assembly also includes at least two support
rollers, one of the support rollers being rotatably
mounted to the first bearing plate, and another of the
support rollers being rotatably mounted to the second
bearing plate. The support rollers are located to engage
the extendable frame such that the extendable frame rolls
along the support rollers when the extendable frame is
moved along the base frame.
Preferably, the support assembly includes at least
three support rollers, two of the support rollers being
rotatably mounted to the first bearing plate for rotation
about axes that are located on opposite sides of the
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first pivot axis. The support rollers are preferably in
parallel alignment with each other and extend
transversely across at least a portion of the base frame.
The support assembly can include four support
rollers, two of the support rollers being rotatably
mounted to the first bearing plate for rotation about
axes that are located on opposite sides of the first
pivot axis, and two of the support rollers being
rotatably mounted to the second bearing plate for
rotation about axes that are located on opposite sides of
the second pivot axis.
According to a further aspect of the invention,
there is provided a telescopic frame having an elongate
base frame and an elongate extendable frame reciprocally
movable in a longitudinal direction along the base frame.
A support assembly is connected to the base frame for
supporting at least a portion of the extendable frame.
The support assembly includes a pair of spaced apart
lever devices pivotally mounted on the base frame to
pivot about substantially aligned primary pivot axes that
are substantially transverse to the longitudinal axes of
the base frame and the extendable frame. Two spaced apart
support rollers are rotatably connected to and extend
between the lever devices. The support rollers have
rotational axes that are located on opposite sides of the
primary pivot axes, and the support rollers extend across
at least a portion of the base frame such that the
extendable frame rolls along the support rollers when the
extendable frame is moved along the base frame.
Preferably, each lever device includes a pivot plate
device pivotally mounted on the base frame to pivot about
the primary pivot axis, and first and second bearing
plates mounted on the pivot plate device to pivot about a
first pivot axis and a second pivot axis respectively,
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the first pivot axis and the second pivot axis being
located on opposite sides of the primary pivot axis. One
of the support rollers is pivotally connected between the
first bearing plates of the lever devices and the other
5 of the support rollers is pivotally connected between the
second bearing plates of the lever devices.
The support assembly can include a further support
roller mounted between the first bearing plates to rotate
about a rotational axis such that the extendable frame
also rolls along the further support roller when the
extendable frame is moved along the base frame, the
rotational axes of the two support rollers mounted
between the first bearing plates being located on
opposite sides of the first pivot axis.
According to still a further aspect of the
invention there is provided a telescopic conveyor system
including an elongate base frame, an elongate extendable
frame mounted to the base frame for longitudinal
reciprocal movement relative to the base frame between a
retracted position and an extended position, conveyor
means mounted to the base frame and the extendable frame
for moving a load along the base frame and the extendable
frame, and a support assembly connected to the base
frame for supporting a portion of the extendable frame.
The support assembly includes a lever device mounted to
the base frame so as to pivot about a primary pivot axis,
and two spaced apart support rollers connected to the
lever device to rotate about axes which are located on
opposite sides of the pivot axis. The support rollers are
located to engage the extendable frame such that the
extendable frame rolls along the support rollers when the
extendable frame is moved along the base frame between
its retracted and extended positions.
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Preferably, the lever device includes a pivot plate
device pivotally mounted on the base frame to pivot about
the primary pivot axis, and first and second bearing
plates mounted on the pivot plate device to pivot about a
first pivot axis and a second pivot axis respectively,
the first pivot axis and the second pivot axis being
located on opposite sides of the primary pivot axis. One
of the support rollers is rotatably connected to the
first bearing plate and the other support roller is
rotatably connected to the second bearing plate. The
telescopic conveyor system can include a further support
roller connected to the first bearing plate to rotate
about a rotational axis such that the extendable frame
also rolls along the further support roller when the
extendable frame is moved along the base frame, the
rotational axes of the two support rollers mounted to the
first bearing plate being located on opposite sides of
the first pivot axis.
A detailed description of the preferred embodiments
is provided below with reference to the following
drawings, in which:
Figure 1, in a side view, illustrates a telescopic
conveyor belt system in accordance with a preferred
embodiment of the present invention, with the extendable
frame of the conveyor belt system in a retracted
position;
Figure 2, in a perspective view, illustrates the
telescopic conveyor belt system of figure 1 with the
extendable frame in an extended position:
Figure 3 illustrates a partial top view of the
telescopic conveyor belt system of figure 1;
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Figure 4 illustrates a side sectional view of a
portion of the telescopic conveyor belt system of figure
1;
Figure 5 is a partial cross-sectional view of a
support assembly for the telescopic conveyor system,
taken along the lines V-V of figure 3;
Figure 6 is a sectional end view of the support
assembly of figure 5;
Figure 7 illustrates a support assembly in
accordance with a further preferred embodiment of the
present invention;
Figure 8 illustrates a support assembly in
accordance with a further preferred embodiment of the
present invention; and
Figure 9 illustrates a support assembly in
accordance with still a further preferred embodiment of
the present invention.
Referring to figures 1 and 2, a telescopic conveyor
belt system, indicated generally by 10, is shown in
accordance with a preferred embodiment of the present
invention. The conveyor belt system 10 includes a
telescopic frame 11 which has an elongate base frame 12
and an elongate extendable frame 14. Both the base frame
12 and the extendable frame 14 have a generally
rectangular cross-section, with the cross-section of the
extendable frame 14 being smaller than the cross-section
of the base frame 12 so that the extendable frame 14 can
be received within the base frame 12. The extendable
frame 14 is telescopically mounted for reciprocal
movement in and out of the base frame 12. Figure 1
illustrates the conveyor belt system 10 with the
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extendable frame 14 in a retracted position and figure 2
illustrates the conveyor belt system 10 with the
extendable frame 14 in a fully extended position.
The base frame 12 and extendable frame 14 each
include a pair of elongate upper support rails 16 and 20,
respectively, and a pair of elongate lower support rails
18 and 22, respectively. The upper support rails 16 and
the lower support rails 18 of the base frame 12 are
interconnected in a conventional manner by a number of
brace members, and the upper support rails 20 and the
lower support rails 22 of the extendable frame 16 are
also connected together by a number of brace members. It
will be appreciated by those skilled in the art that the
use of support rails which are interconnected by braces
is conventionally used in large scale telescopic frame
structures in order to maximize the strength of the frame
while minimizing its weight.
The conveyor belt system 10 includes a first
conveyor belt 24, which is mounted on the base frame 12,
and a second conveyor belt 26, which is mounted on the
extendable frame 14. As best seen in Figure 2, the first
conveyor belt 24 is mounted such that its load carrying
surface is located above upper support rails 16 of the
base frame 12, and the second conveyor belt 26 is mounted
such that its load carrying surface is located below the
upper support rails 20 of the extendable frame 14. This
configuration provides the necessary clearance for
retracting the extendible frame 14 within the base frame
12. Conveyor belts 24 and 26 are mounted on their
respective frames for movement in a conventional manner,
and when in operation serve to move a load such as
aggregate from a feed end 28 of the conveyor system
(located at the lower end of the base frame 12) to a
discharge end 30 of the conveyor system (located at an
upper end of the extendable frame 14).
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The conveyor belt system 10 makes use of an actuator
means known in the art for extending and retracting the
extendable section 14.
The telescopic frame 11 of the conveyor belt system
is preferably mounted on a support frame 32, such that
telescopic frame 11 can be raised and lowered and also
transported from place to place. Support frame 32
includes a horizontal frame 34, to which the base frame
10 12 is pivotally mounted in the vicinity of its feed end
28. A hydraulic lift frame 36 is provided for elevating
and lowering the telescopic frame 11. The support frame
32 preferably includes wheel assemblies 38 which can be
rotated about the horizontal frame 34 between a use
position as shown in figures 1 and 2, and a transport
position (not shown). In the use position, the wheel
assemblies 38 extent substantially transversely from the
longitudinal axis of the telescopic frame 11 and allow
the conveyor belt system 10 to be radially rotated about
its feed end 28. In the transport position, the wheel
assemblies 38 extend parallel to the longitudinal axis of
the telescopic frame 11, and permit the conveyor belt
systems 10 to be towed from place to place (preferably
with the extendable frame 14 in a fully retracted
position, and the telescopic frame 11 in a fully lowered
position). Thus the conveyor belt system 10 is a
portable, telescopic, radial conveyor belt system which
can be used for a number of applications, including
forming non-segregated piles of aggregate. Conveniently,
the conveyor belt system 10 may also include wheels (not
shown) located at its feed end 28 so that the system 10
can be moved in a lateral direction as well as
longitudinally without having to raise the feed end 28 up
off of its supports.
The present invention is particularly directed to
the manner in which the extendable frame 14 is mounted
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for reciprocal movement along the base frame 12. With
reference to figures 3 and 4, the extendable frame 14 is
supported by a first support assembly 40 located near the
outer end 42 of the base frame from which the extendable
5 frame 14 extends and retracts, and a second support
assembly 44 located on the base frame 12 at a distance
off-set from the outer end 42. The first support
assembly 40 engages and supports the underside of the
extendable frame 14, and the second support assembly 44
10 engages and supports the top side of the extendable frame
14.
The first support assembly 40 and the second support
assembly 44 are substantially identical, with the primary
difference between the two being that the second support
assembly 44 is inverted relative to the first support
assembly 40. Each of the support assemblies 40 and 44
are secured to the base frame 12 by a pair of spaced
apart support members 46 which are rigidly secured to and
are a part of the base frame 12. As seen in figures 3 and
4, the support members 46 used to secure the first
support assembly 40 extend upwardly along opposite sides
of the base frame 12. Similarly, the support members 46
of the second support assembly 44 also extend upwardly on
opposite sides of the base frame 12. Conveniently, the
support members 46 may be constructed from 4" by 4" inch
hollow rectangular tubing formed from steel having a 3~8"
thickness, however the support members 46 could take a
wide variety of other shapes and sizes.
With reference to the first support assembly 40, the
construction of a support assembly in accordance with one
preferred embodiment of the present invention will now be
described in greater detail. The support assembly 40
includes two substantially identical lever devices,
indicated generally by 48, which support four spaced
preferably parallel support rollers 50 which extend
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transversely across the base frame 12 for supporting the
extendable frame 14. The lever devices 48 are each
pivotally mounted at opposite sides of the base frame 12
to a lower portion of one of the support members 46 of
the first support assembly 40.
With reference to figures 5 and 6, one of the lever
devices 48 of the first support assembly 40 will now be
described in greater detail. Each lever device 48
includes a pivot plate device 52 which is pivotally
mounted on the support member 46, and first and second
bearing plates 53 which are each in turn pivotally
mounted on the pivot plate 52. The bearing plates 53
each are adapted to support one end of two of the support
rollers 50.
As best seen in figure 6, each pivot plate device 52
is preferably formed from two substantially identical
parallel plates 57 which are spaced apart by a circular
spacer 59 which has substantially the same thickness as
the bearing plates 53. The pivot plate device 52 is
mounted on the support member 46 by a pin 54, which
extends through aligned holes provided in the plates 57,
the spacer 59, and the support member 46. Preferably,
rectangular flat bars 55 are rigidly secured to opposite
sides of the support member 46 in the region where the
pin 54 passes through in order to increase the strength
of the support member 46. The pin 54 preferably has an
enlarged circular head 56 at one end for engaging the
pivot plate 52 device, and is threaded at its opposite
end for receiving a bolt 58 on which is mounted a
circular washer 60 which has an area larger than the
cross-section of the hole through which the pin 54
extends. The shaft of the pin 54 preferably has an
overall length slightly longer than the combined total
thickness of the plates 57, the spacer 59, the flat bars
55, and the support member 46, in order to permit the
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pivot plate device 52 to pivot about a primary pivot
plate pivot axis provided by pin 54.
An upper portion of each of the first and second
bearing plates 53 extends between the two plates 57 of
the pivot plate device 52, and each of the bearing plates
53 is pivotally mounted to plates 57 by a bolt 61 which
extends through aligned holes provided through the plates
57 and the bearing plate 53 and serves as a pivot pin.
The bolt 61 is preferably secured with a nut. Washers 62
are preferably located between each of the head and nut
of the bolt 60 and the plates 57. In this manner, the
first and second bearing plates 53 are each mounted on
the pivot plate device 52 to pivot about a first bearing
plate pivot axis and a second bearing plate pivot axis,
respectively, the pivot axes being provided by the bolts
60. As best seen in figure 5, the bearing plates 53 are
mounted on pivot plate device 52 such that the first
bearing plate pivot axis and the second bearing plate
pivot axis are located on opposite sides of the pivot
axis of the pivot plate device 52. In this regard, the
pivot plate device 52 acts as a first class lever with
its pivot axis being the fulcrum, and the pivot axes of
the first and second bearing plates 53 acting as load
points. Conveniently, the first and second bearing plate
pivot axes may be equidistant from the pivot plate pivot
axis such that the degree of force applied to each of the
bearing plates 53 by the pivot plate device 52 will be
equal.
The two lever devices 48 of the first support
assembly 40 are pivotally mounted to opposite sides of
the base frame 12 in alignment with each other such that
their respective primary pivot axis and first and second
bearing plates pivot axes are substantially transverse to
the longitudinal axes of the base frame 12 and extendable
frame 13. Two support rollers 50 extend between and are
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pivotally mounted to the first bearing plates 53 of the
two lever devices 48, and two support rollers 50 extend
between and are pivotally mounted to the second bearing
plates 53. As best seen in figure 5, the support rollers
50 are positioned such that the rotational axes of the
two rollers mounted to a particular bearing plate 53 are
located on opposite sides of the bearing plate pivot axis
of that particular bearing plate. Thus, each bearing
plate 53 is itself a first class lever, with its pivot
axis serving as a central fulcrum located between the
rotational axes of the two rollers 50 which are mounted
thereon.
With reference to figure 6, the manner in which each
support roller 50 is connected to a bearing plate will
now be discussed. Each roller 50 preferably includes an
elongate central hollow steel tube section 64 and has
solid steel stub sections 66 located at both ends of the
tube section 64. Each stub 66 includes a cylindrical load
bearing portion 68 and a cylindrical connecting portion
70 which has a cross-section less than that of the load
bearing portion 68. The stubs 66 may be connected to the
end of the tube 64 by press fitting the stubs 66 into
tube 64 and then welding the stubs to the tube. In order
to facilitate a press fit connection each stub 66 is
provided with fit stub 72.
The connecting portion 70 of each stub 66 is used to
pivotally connect an end of the roller 50 to one of the
bearing plates 53. Each bearing plate 53 includes two
adjacent holes which are located on opposite sides of the
bearing plate pivot axis, each for receiving the
connecting portion 70 of one of the rollers 50. These
holes in the bearing plate each preferably have a
diameter which is somewhat larger than the diameter of
the connecting portion 70 it will receive, and are each
covered by pilot bearings 74 which are secured to the
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surface of the bearing plate 53 facing the roller 50.
Each pilot bearing 74 has a hole formed therethrough
which is dimensioned to accommodate the diameter of the
connecting portion 70 of the stub 66. The pilot bearings
74 are each preferably secured to their respective
bearing plates 53 by four bolts 76 (which can be secured
by nuts, or be secured by tapped bores provided in the
pilot bearing). A bushing 78 is provided on the
connecting portion 70 of each of the rollers 50 for
location between the load bearing section 68 and the
pilot bearing 74 to limit lateral movement of the roller
50. Ball bearings or other means may be provided in the
interface between the pilot bearing 74 of the bearing
plate 53 and the connecting portion 70 in order to
facilitate rotation of the rollers 50. The support
rollers 50 of the first support assembly 40 are mounted
such that the bottom surface of the lower support rails
22 of the extendable frame 14 engage the load bearing
portions 66 of the rollers 50.
As previously mentioned, the second support assembly
44 is substantially identical to the first support
assembly 40 except that it is inverted. In this regard,
the load bearing portions 66 of the rollers 50 in the
second support assembly 44 engage the top surface of the
upper support rails 20 of the extendable frame 14. As can
be seen with reference to the second support assembly 44
in figure 4, the support assemblies may be provided with
grease line hoses 80 leading to the connecting portions
70 of stubs 66 in order to allow the rollers 50 to be
easily greased.
In operation, the extendable frame 14 is extended
and retracted by actuator means known in the art. As it
extends and retracts, it travels along and is supported
by rollers 50 of the first 40 and second 44 support
assemblies. In particular the lower support rails 22
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each ride along the four support rollers 50 of the first
support assembly 40, and the upper support rails 20 each
ride along the four support rollers 50 of the second 44
support assembly as the extendable frame 14 is moved
5 between its extended and retracted positions. The first
40 and second 44 support assemblies act as the interface
between the extendable frame 14 and the base frame 12. As
mentioned above, the degree of curvature of the
extendable frame 14 along its longitudinal axis will vary
10 depending on location of the extendable frame 14 relative
to the base frame 12, and also on a load applied to the
extendable frame 14. Because of the pivotal nature of
the support assemblies 40 and 44 of the present
invention, they automatically adjust to the changes in
15 curvature of the extendable frame 14 that occur, thus
ensuring that the force applied by the extendable frame
14 on the first support assembly 40 is proportionately
distributed across all four rollers 50 of the assembly
40, and similarly that the force applied by the
extendable frame 14 on the second support assembly 44 is
proportionately distributed across all four rollers of
the assembly 44. Thus, no single roller 50 is subjected
to bearing a disproportionate amount of weight, and
additionally, the extendable frame 14 is not subjected to
a disproportionate amount of force in the vicinity of
just one roller. Where the support assemblies 40 are each
constructed in a bisymmetrical manner, (i.e., the rollers
50 are each located the same perpendicular distance from
the pivot axis of the bearing plates they are secured to,
and the pivot axes of the first and second bearing plates
are equally spaced relative to the primary pivot axis of
the pivot plate device), then the load applied the
rollers 50 within a support assembly will substantially
be equally distributed across each of the rollers
regardless of any curvature experienced by the extendable
frame 14. As a result of the improved distribution of
force, at least some of the rollers 50 are subjected to
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less stress and may have a longer life span than if they
were mounted independently of each other on the base
frame 12. Additionally, as no single section of the
extendable frame 14 is subjected to a disproportionate
amount of force by a single support roller, the
extendable frame 14 can be constructed from lighter or
lower yield strength materials than if independently
supported rollers were used.
In the preferred embodiment illustrated, the bearing
plates 53 and flat bars 55 are preferably formed from
steel plate having a thickness of 5/8 ", and the plates
57 are formed from steel plates having a thickness of 3~8
°'. It will of course be appreciated that different
materials having different thicknesses could be used as
appropriate.
It will be appreciated that the support assemblies
40 and 44 could be constructed in other ways then
described above. For example, the pivot plate device 52
may comprise only a single plate 57, rather than two
plates 57. Furthermore, although each lever device 48 is
used to support four rollers 50, depending upon the size
of the telescopic frame, lever devices which support more
or less than four rollers could be used.
In this respect, figure 7 illustrates a support
assembly having a lever device 82 constructed in
accordance with a second preferred embodiment of the
invention. The lever device 82 is similar to the lever
device 48, except as hereafter noted. The lever device
82 supports only three rollers 50, and would be suitable
for use in smaller telescopic frames. Two of the rollers
are supported by one bearing plate 53, and one roller is
supported by another bearing plate 84. The bearing
plates 53 and 84 are each pivotally mounted on a pivot
plate device 86, which is in turn pivotally mounted on
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support member 46. The lever device 82 functions similar
to lever device 48 to ensure that all rollers 50 remain
in contact with the extendable frame 14 regardless of the
curvature of the frame 14. In applications where it is
desirable that all the rollers 50 be subjected to
substantially the same degree of force, the perpendicular
distance from the pivot axis of the bearing plate 84 to
the pivot axis of the pivot plate device 86 is twice that
of perpendicular device from the pivot plate device pivot
axis to the pivot axis of the bearing plate 53, and the
rollers 50 connect to plate 53 are equally spaced on
opposite sides of the pivot axis of the plate 53.
It will be appreciated that a number of support
assembles as described above could be combined together
to provide larger support assemblies for larger
telescopic frames. For example, figure 8 illustrates a
further support assembly 88 which includes two lever
devices 82 pivotally mounted on opposite ends of a main
pivot plate 90 which is pivotally mounted on support
member 46. Figure 9 illustrates still a further support
assembly which includes two lever devices 48 pivotally
mounted on opposite ends of main pivot plate 90, which is
in turn pivotally mounted on support member 46.
Thus, it will be appreciated that the support
assembly of the present invention could be implemented
using a number of different configurations. By way of
further example, in some applications it may be
sufficient to attach only a single support roller to the
first and second bearing plates 53 of the support
assemblies 40 and 44. In other applications, it may be
possible to attach the rollers directly to the pivot
plate without any intervening bearing plates.
As described above, each support assembly 40 or 44,
includes two lever devices located opposite each other to
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support opposite ends of a support roller. However in
some applications it may not be necessary that the
support rollers extend between the two load supporting
devices, but rather that each lever device independently
support rollers that are not connected to another lever
device, and accordingly in such devices a support
assembly could includes just a single lever device.
Although the above description has focused on the
use of the support assembly in the context of a
telescopic frame for a conveyor belt assembly, it will be
appreciated that the support assembly could be used with
telescopic frames used for other purposes.
While various embodiments of this invention have
been illustrated in the accompanying drawings and
described above, it will be evident to those skilled in
the art that changes and modifications may be made
therein without departing from the essence of this
invention. All such modifications and variations are
believed to be within the sphere and scope of the
invention as defined by the claims appended hereto.
