Note: Descriptions are shown in the official language in which they were submitted.
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BELTED COMPACTION APPARATUS KIT AND METHOD
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to United States Provisional
application No. 62/351,032 filed June 16, 2016, which is hereby incorporated
by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates to belted compaction apparatus
for compacting surfacing materials such as asphalt or portland cement
concrete.
BACKGROUND
[0003] Machines such as compactors are often employed to compact
soil, gravel, asphalt, and other materials. Most commonly, these machines
include rotating steel drum compactors. A typical steel drum compactor has
a drum assembly with one or more drums for compacting the material. The
steel drum compactors can be static or dynamic (vibratory or oscillatory).
For example, in dynamic steel drum compactors, the drum assembly may
include a vibratory mechanism having two or more weights arranged on a
shaft rotatable about a common axis within an interior cavity of the drum for
inducing vibrations on the drum.
[0004] A significant problem which has not been adequately addressed
is that of cracking of the asphalt that has been compacted using
conventional steel drum rollers. This phenomenon is called "roller checking"
and is believed to be caused by the incompatibility of the hard, round steel
drum and the soft, flat asphalt pavement. Furthermore, conventional steel
drums are round and only a very small area of contact is presented to the
asphalt surface for compaction. As the roller travels along the pavement,
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the asphalt in front of the roller is pushed ahead, causing a pulling force in
the asphalt behind the drum. This pushing and pulling action causes the
asphalt to crack. Cracks in the pavement are the forerunner of the pothole
which forms when water seeps into cracks in a road surface, freezes and
expands the pavement. When the ice melts the pavement is shattered by
vehicles running thereover.
[0005] Another challenge encountered with the use of conventional
steel drum rollers is their limited use on bridge decks due to the softness of
the underlying waterproofing system and restrictions on the levels of
vibration that may be imparted.
[0006] Accordingly, there is a need for a system that is flexible,
economical, and addresses the deficiencies seen in prior art compactors.
SUMMARY OF THE INVENTION:
[0007] It is an embodiment of the present invention to provide a belted
asphalt compactor conversion kit for converting a drum roller compactor into
a belted asphalt compactor, the kit comprising:
a belted compaction apparatus securable to the frame of the compactor,
the apparatus comprising:
a body;
a pair of leading rollers at one end of the body and a pair of trailing
rollers at the other end of the body;
a plurality of intermediate rollers disposed between the leading and
trailing rollers;
a drive wheel; and
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a belt wound around the leading, trailing, and intermediate rollers,
and the drive wheel, wherein the leading, trailing, and intermediate
rollers exert a substantially downward pressure on the bottom run of
the belt to provide a uniform pressure applying surface over the area
of the belt in contact with the asphalt.
[0008] According to another aspect there is provided a belted asphalt
compactor conversion kit for converting a dual drum roller compactor having
a front drum and a rear drum into a belted asphalt compactor, the kit
comprising:
a leading compaction assembly which replaces the front drum roller of
the drum roller compactor;
a trailing compaction assembly which replaces the rear drum roller of the
drum roller compactor, wherein each assembly comprises a plurality of
belted compaction apparatus arranged in a side-by-side configuration,
each of said apparatus comprising:
a body securable to the frame of the compactor;
a pair of leading rollers at one end of the body and a pair of trailing
rollers at the other end of the body;
a plurality of intermediate rollers disposed between the leading and
trailing rollers;
a drive wheel; and
a belt wound around the leading, trailing, and intermediate rollers,
and the drive wheel, wherein the leading, trailing, and intermediate
rollers exert a substantially downward pressure on the bottom run of
the belt to provide a uniform pressure applying surface over the area
of the belt in contact with the asphalt.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Fig. 1 is a side view partial sectional view of a belted asphalt
compactor according to an embodiment of the invention;
[0010] Fig. 2 is a perspective view of the rear of the compactor
showing a trailing compaction assembly comprising two belted compaction
apparatus;
[0011] Fig. 3 is a rear view of the compactor showing the trailing
compaction assembly;
[0012] Fig. 4 is a perspective view of the rear of the compactor
showing the trailing compaction assembly with the shroud removed;
[0013] Fig. 5 is another perspective view of the rear of the compactor
showing the trailing compaction assembly with the shroud removed;
[0014] Fig. 6 is a perspective view of the compaction assembly
according to an embodiment of the invention;
[0015] Fig. 7 is another perspective view of the compaction assembly
according to Fig. 6;
[0016] Fig. 8 is a perspective view of a belted compaction apparatus
with the belt removed according to an embodiment of the invention;
[0017] Fig. 9 is a rear view of the belted compaction apparatus with
the belt removed;
[0018] Fig. 10 is an enlarged side view of the belted compaction
apparatus installed as part of the trailing compaction assembly on the frame
of the conventional compactor;
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[0019] Fig. 11 is a rear view of the belted compaction apparatus
installed as part of the trailing compaction assembly on the frame of a
conventional compactor; and
[0020] Fig. 12 is a perspective view of the belt for use with the belted
compaction apparatus;
[0021] Fig. 13 is a perspective view of a compaction assembly
according to another embodiment of the invention showing the belt
tensioner;
[0022] Fig. 14 is a side elevation view of the compaction assembly
according to figure 6;
[0023] Fig. 15 is a side elevation view of a compaction assembly
according to another embodiment of the invention
[0024] Fig. 16a is side elevation view of a body reinforcing member
according to an embodiment of the invention;
[0025] Fig. 16b is front view of the body reinforcing member according
to Fig. 16a showing the leading rollers;
[0026] Fig. 17 is a perspective view of a belted asphalt compactor
according to another embodiment of the invention showing weighted
members secured to the frame;
[0027] Fig 18 is a front view in partial transparency showing the
weighted members according to an embodiment of the invention.
DETAILED DESCRIPTION
[0028] Reference will be made below in detail to exemplary
embodiments of the invention, examples of which are illustrated in the
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accompanying drawings. Wherever possible, the same reference numerals
used throughout the drawings refer to the same or like parts.
[0029] Referring to the accompanying drawings, there is illustrated a
belted compaction apparatus generally indicated by reference numeral 10.
Shown in figure 1 is a belted asphalt compactor 12 including the belted
compaction apparatus 10 for compacting surfacing materials 2, such as
asphalt. As will be discussed below, the belted compaction apparatus 10 is
particularly suitable for converting a conventional dual drum roller compactor
into the belted asphalt compactor 12. In the embodiment shown, the
compactor 12 may be derived using any conventional articulated compactor
comprising a frame 14.
[0030] Compactor 12 comprises a leading compaction assembly 16
forward of an articulation point 18 and a trailing compaction assembly 20
rearward of the point of articulation. Each one of the compaction assemblies
16, 20 comprise two apparatus 10 arranged in a side-by-side relationship
spanning substantially the entire width of the compactor 12 as will be
described in greater detail below.
[0031] As shown in greater detail in figures 2 to 11 and 13, each
individual apparatus 10 comprises an elongate body 30 securable to the
frame 14 of the compactor 12. In the embodiment shown, the body 30 is in
the shape of a triangle, when observed from the side and includes an
aperture 32.
[0032] In the embodiment shown in figures 5 and 6, the body 30 is
securable to the frame 14 by an attachment means 40. The attachment
means 40 comprises a cylindrical transverse brace 42 that may extend from
one side of the frame 14 to the opposite side of the frame 14 by passing
through the aperture 32 in the body 30 and rotatably mounted to bearings
44 which are secured to the frame 14. Attachment means 40 is configured
to permit rotation of apparatus 10 about the frame 14 so that the apparatus
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may be able to better follow any elevation changes in the contour of the
surface below. In other embodiments, the attachment means 40 is
configured to permit the removable attachment of the body 30 to the frame
14. In some embodiments, the attachment means 40 comprises trailer
hitches, fifth wheel couplings, and clamps.
[0033] As shown in greater detail in figures 2 to 7 and 12, apparatus
10 further comprises a belt 50. Belt 50 comprises an outer surface 52 which
contacts the surface material and an interior surface 54. A plurality of belt
retaining members 56 (also known as cogs 56) are provided in interior
surface 54 for securing belt 50 to the apparatus 10 as will be described
below. The belt 50 may be formed of any suitable material taking into
account the specific requirements of any particular application of the
compactor. Thus, the belt 50 may comprise resilient material such as
laminated rubber which will generally provide a suitable surface texture to
the compacted asphalt, for example. In one embodiment, the belt 50
comprises multiple layers and can be a laminated rubber belt having a
harder outer layer for contacting the asphalt and a softer inner layer. In
another embodiment, the outer and inner layers have a different texture,
wherein the outer layer in contact with the surfacing material may have a
smooth texture.
[0034] A pair of leading rollers 60 is provided at one end of the body
30 and a pair of trailing rollers 62 is provided at the other end of the body
30. As shown in the figures, the leading and trailing rollers 60, 62 are
disposed at the base of the body 30.
[0035] A plurality of intermediate rollers 70 is disposed between the
leading 60 and trailing 62 rollers. As depicted, there are three pairs of
intermediate rollers (70a, 70b and 7c), where each of the intermediate
rollers 70 has a smaller diameter than the leading rollers 60. As shown in
the figures, the intermediate rollers 70 are disposed at the base of the body
30.
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[0036] Leading 60 and trailing 62 rollers may comprise multiple layers
including a solid metal core 64 surrounded by one or more outer layers 66
made of different material than the core. In one embodiment, the core of
the leading and trailing rollers is steel and the outer layer is a resilient
material.
[0037] Similarly, intermediate rollers 70 may comprise multiple layers
including a solid metal core 74 surrounded by one or more outer layers 76
made of different material than the core. In one embodiment, the core of
the intermediate rollers 70 is steel and the outer layer 76 is a resilient
material.
[0038] Apparatus 10 further comprises a drive wheel 80 that is
rotatably secured at a distance above and separated from the leading 60,
trailing 62 and intermediate rollers (70a, 70b and 7c). Drive wheels 80 are
powered and each of the drive wheels 80 may be rotated by their own drive
motor 81 which can be supported by a motor support 84 secured to the body
30. In an embodiment, the drive wheels 80 are rotated using rotational
force generated by one or more hydraulic motors which may be powered by
a main engine 22 of the compactor.
[0039] Leading 60, trailing 62, and intermediate rollers 70 define a
planar bottom run of the belt 52, whereby the bottom run 52 of the belt 50
defines the compaction surface of the apparatus 10. In this manner, the
leading 60, trailing 62, and intermediate rollers 70 exert a substantially
downward pressure on the bottom run 52 of the belt 50 to provide a uniform
pressure applying surface over the area of the belt 50 in contact with the
surfacing material 2. Without being limited to any particular theory, the
apparatus 10 creates a larger footprint allowing the compaction process to
take place over a longer period of time to compress any air out of the
compacted surfacing material and provide for better quality compaction of
asphalt, for example.
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[0040] As shown, the belt 50 is wound around the leading 60, trailing
62, and intermediate rollers 70, and the drive wheel 80. Each one of the
pair of the leading rollers 60, trailing rollers 62, and intermediate rollers
70
are separated from the other pair by a gap 82. Gap 82 is dimensioned to
receive belt retaining members 56 to secure the belt 50 to the apparatus 10
when the belt 50 is wound around the body 30. In some embodiments,
when the belt 50 is wound around the rollers and the wheel, and the belt
retaining members 56 are inserted into the gap 82, the belt 50 may resist
lateral slippage during use where use may include operation on unlevel
surfaces such as superelevation.
[0041] As will be expected, when the drive wheel 80 is caused to
rotate, the belt 50 will turn and will act as an endless track for the leading
60, trailing 62, and intermediate rollers 70 and the compactor 12 will move
in a direction desired by the operator.
[0042] The compactor 12 may also be equipped with a number of
accessories that are advantageous for the compaction process.
[0043] The belt 50 may be heat resistant and in some aspects, may be
subjected to at least the temperature suitable for compacting freshly laid
asphalt, for example about 120 C to about 150 C or more before or during
the compaction process. In some aspects, the heating of the belt 50 may
also ensure that the bitumen on the surface of the asphalt substantially does
not adhere to the belt 50. The belt 50 may be heated by any suitable
means, for example a super-heated air generator or direct flame heating
such as propane flame heating.
[0044] A thermal insulating shroud 90 which overlies the belted
compaction apparatus 10 or the compaction assemblies 16, 20 may also be
provided. Shroud 90 alleviates heat loss from those portions of the belt 50
not in contact with the surface of the asphalt. The shroud 90 may be formed
in part or wholly by an insulating shroud and advantageously extends over
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the belt 50 at least substantially to the level of the compaction surface.
Shroud 90 may be formed in one or more parts, for example from reinforced
plastics such as fiberglass or a metal such as aluminum or steel with or
without insulation.
[0045] A scraper bar may be provided to remove excess asphalt fines
accumulated on the belt during the surfacing material compaction process.
An asphalt fines collection means may also be provided to collect the excess
asphalt fines so that the excess asphalt fines are kept away from the
compacted surface.
[0046] A belt degreasing means and a degreaser reservoir may be
provided for degreasing the belt 50 during the surfacing material compaction
process.
[0047] The compactor may be equipped with a plurality of sensors to
monitor speed, direction, and location. Additional sensors measuring
temperature of the material to be compacted may also be used. Belt edge
sensors may also be provided to detect the lateral position of the edges of
the belt so the operator can adjust the direction of the compactor. The
compactor may also include a microprocessor to continuously monitor the
above-listed parameters to automatically adjust any one of the parameters
to provide for better quality of compaction.
[0048] One or more belt guides disposed adjacent to the belt may be
provided to tension and guide the belt along its intended path, for example.
In one embodiment as shown in figure 13, the belted compaction apparatus
may also comprise a belt tensioner 92 secured to the body 30. Belt
tensioner 92 comprises at one end an axle housing 94 configured to
rotatably receive the axle of the leading rollers 60 therein and a piston 96
at
the other end. As shown, a free end of the piston 96 is secured to the body
30 and actuation of the piston 96 will permit sliding movement of the axle
housing 94, and therefore the leading wheels 60, in relation to the body 30.
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The tension on the belt 50 being adjustable by the movement of the piston
96 because the belt 50 is wound around the leading 60, trailing 62, and
intermediate rollers 70, and the drive wheel 80. In some embodiments, the
pressures exerted on the belt 50 are about 2000 lbs.
[0049] The compactor 12 and apparatus 10 may be configured to suit
many different types of applications and environments wherein the
dimensions of each of the components can be adjusted for results considered
optimal for the particular application. For example, as shown in figure 14,
apparatus 10 may be configured to have the depicted dimensions which
result in an overall weight of 8.90 t or 19621.14 lbs; a surface area of
3797.25 in2; to exert a ground pressure of 5.17 psi or 35.6 kPa.
[0050] In another embodiment as shown in figure 15, apparatus 10
may be configured to have the depicted dimensions which result in an overall
weight of 8.90 t or 19621.14 lbs; a surface area of 3085 in2; to exert a
ground pressure of 6.36 psi or 43.8 kPa. It is revealed that in some
applications that a ground pressure of at least 6 psi can achieve optimum
results.
[0051] As shown in figures 16a and 16b, apparatus 10 may further
comprise a pair of body reinforcing members 100 which add structural
support and rigidity to the body 30.
[0052] As shown figures 17 and 18, compactor 12 further comprises
weighted members 110 secured to the frame 14. The weighted members
110 are configured to adjust the overall weight of the compactor 12 so that
the apparatus 10 (and therefore the compaction assemblies 16, 20) may be
able exert an optimal ground pressure for a specific application.
[0053] In one embodiment, the method of converting a conventional
dual drum roller compactor to the belted asphalt compactor 12 converted
comprises the steps of decoupling the drum rollers from the frame of the
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conventional dual drum roller compactor, and hoisting the frame to facilitate
the removal of the drum rollers from underneath the frame. Positioning one
or more of the apparatus 10 underneath the frame and lowering the frame
onto one or more of the apparatus 10. Securing the apparatus 10 to the
frame using an attachment means 40. Wherein the securing comprises
inserting a traverse brace 42 into an aperture 32 of the apparatus 10,
securing bearings 44 to the frame 14, and then coupling the brace 42 to the
bearings 44. Operationally connecting the drive wheel 80 to at least one
drive motor 81.
[0054] The embodiments of the present application described above
are intended to be examples only. Those of skill in the art may effect
alterations, modifications and variations to the particular embodiments
without departing from the intended scope of the present application. In
particular, features from one or more of the above-described embodiments
may be selected to create alternate embodiments comprised of a
subcombination of features which may not be explicitly described above. In
addition, features from one or more of the above-described embodiments
may be selected and combined to create alternate embodiments comprised
of a combination of features which may not be explicitly described above.
Features suitable for such combinations and subcombinations would be
readily apparent to persons skilled in the art upon review of the present
application as a whole. Any dimensions provided in the drawings are
provided for illustrative purposes only and are not intended to be limiting on
the scope of the invention. The subject matter described herein and in the
recited claims intends to cover and embrace all suitable changes in
technology.
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