Note: Descriptions are shown in the official language in which they were submitted.
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VARIABLE GEOMETRY METER ROLLER
[0001]
BACKGROUND
[0002] The invention
relates generally to metering systems and, more particularly,
to a metering device with variable geometry.
[0003] Generally,
seeding implements are towed behind a tractor or other work
vehicle. These seeding implements typically include one or more ground
engaging
tools or openers that form a seeding path for seed deposition into the soil.
The
openers are used to break the soil to enable seed deposition. After the seeds
are
deposited, each opener is followed by a packer wheel that packs the soil on
top of the
deposited seeds.
[0004] In certain
configurations, an air cart is used to meter and deliver
agricultural product (e.g., seeds, fertilizer, etc.) to ground engaging tools
within the
seeding implement. Certain air carts include a metering system and air
conveyance
system configured to deliver metered quantities of product into an airflow
that
transfers the product to the openers. However, the metering system may include
meter rollers with a limited ability to control product flow. For example,
some meter
rollers may have a uniform geometric shape that does not compensate for a
change in
product size. With such meter rollers, an undesirable quantity of product may
be
metered and/or the cross sectional area of the flutes may be insufficient to
meter
product having large diameter particles. Thus, an operator will typically
replace
meter rollers when switching between products. Consequently,
multiple
assembly/disassembly steps may be involved, thereby decreasing productivity
and
increasing planting costs.
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BRIEF DESCRIPTION
[0005] In one embodiment, an agricultural metering device includes a meter
roller
having a plurality of flutes. An aggregate cross sectional area of the flutes
increases
along a longitudinal axis of the meter roller.
[0006] In another embodiment, an agricultural metering device includes a
meter
roller having a plurality of ridges extending between a first longitudinal end
of the
meter roller and a second longitudinal end of the meter roller. The metering
device
also includes a plurality of flutes. Each flute is formed between a pair of
adjacent
ridges. The metering device includes a cross sectional area of each flute in a
plane
generally parallel to the first and second longitudinal ends which increases
along a
longitudinal axis of the meter roller.
[0007] In another embodiment, an agricultural metering device includes a
meter
roller. The meter roller includes a first longitudinal end, a second
longitudinal end,
and a longitudinal passage extending through the meter roller from the first
longitudinal end to the second longitudinal end. The longitudinal passage is
configured to receive a drive shaft. The meter roller also includes a
plurality of flutes
extending between the first and second longitudinal ends. A cross sectional
area of
each flute in a plane generally parallel to the first and second longitudinal
ends
increases along a longitudinal axis of the meter roller.
DRAWINGS
[0008] These and other features, aspects, and advantages of the present
invention
will become better understood when the following detailed description is read
with
reference to the accompanying drawings in which like characters represent like
parts
throughout the drawings, wherein:
[0009] FIG. 1 is a side view of an air cart having a metering system that
may
utilize a variable geometry meter roller;
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[0010] FIG. 2 is a schematic diagram of an exemplary metering system which
may
be employed within the air cart of FIG. 1;
[0011] FIG. 3 is a perspective view of an embodiment of a metering system
with
meter rollers having a parallel rotational axis;
[0012] FIG. 4 is a cross-sectional side view of a meter box of the metering
system
of FIG. 3;
[0013] FIG. 5 is a schematic diagram of another embodiment of a metering
system;
[0014] FIG. 6 is a top view of an embodiment of a metering system having a
meter
roller sleeve assembly;
[0015] FIG. 7 is a top view of the meter roller sleeve assembly of FIG. 6,
illustrating meter roller sleeve adjustment;
[0016] FIG. 8 is a perspective view of an embodiment of a meter roller
having
variable geometry flutes;
[0017] FIG. 9 is a cross-sectional side view of the meter roller of FIG. 8,
taken
along line 9-9; and
[0018] FIG. 10 is a cross-sectional side view of the meter roller of FIG.
8, taken
along line 10-10.
DETAILED DESCRIPTION
[0019] FIG. 1 is a side view of an air cart having a metering system that
may
utilize a variable geometry meter roller. In the illustrated embodiment, an
implement
is coupled to an air cart 12 such that the air cart 12 towed behind the
implement 10
during operation and transport. The implement 10 includes a tool frame 14 with
a
ground engaging tool 16. The ground engaging tool 16 is configured to excavate
a
trench into the soil 18 for seed and/or fertilizer deposition. In the
illustrated
embodiment, the ground engaging tool 16 receives product (e.g., seeds,
fertilizer, etc.)
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from a product distribution header 20 via hose 22 extending between the header
20
and the ground engaging tool 16. Although only one ground engaging tool 16,
product distribution header 20, and hose 22 are employed within the
illustrated
embodiment, it should be appreciated that the implement 10 may include
additional
tools 16, headers 20 and/or hoses 22 in alternative embodiments to facilitate
product
delivery to the soil 18. As illustrated, the implement 10 includes wheel
assemblies 24
which contact the soil surface 18 and enable the implement 10 to be pulled by
a tow
vehicle.
[0020] As previously discussed, the air cart 12 is coupled to the implement
10, and
towed behind the implement 10. As will be appreciated, in certain embodiments,
the
air cart 12 may be towed directly behind a tow vehicle, with the implement 10
towed
behind the air cart 12. Likewise, the implement 10 and the air cart 12 may be
part of
a single unit, or the implement 10 and the air cart 12 may be separate units
that are
coupled together.
[0021] The air cart 12 includes a storage tank 26, a frame 28, wheels 30, a
metering system 32, and an air source 34. The frame 28 includes a towing hitch
configured to couple to the implement 10 or tow vehicle. In certain
configurations,
the storage tank 26 includes multiple compartments for storing various
flowable
particulate materials. For example, one compartment may include seeds, and
another
compartment may include a dry fertilizer. In such configurations, the air cart
12 may
be configured to deliver both the seeds and fertilizer to the implement 10.
Seeds
and/or fertilizer within the storage tank 26 are gravity fed into the metering
system 32.
[0022] In the present embodiment, the metering system 32 includes sectioned
meter rollers to regulate the flow of material from the storage tank 26 into
an air flow
provided by the air source 34. The air flow then carries the material through
a hose
36 to the implement 10, thereby supplying the ground engagement tool 16 with
seeds
and/or fertilizer for deposition within the soil. Although only one hose 36 is
included
in the illustrated embodiment, additional hoses may be may be employed in
alternative embodiments to transfer product from the air cart 12 to the
implement 10.
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[0023] A control assembly may be communicatively coupled to the metering
system 32 and the air source 34 to regulate flow of product to the implement
10. The
control assembly may include a spatial locating device, such as a Global
Positioning
System (GPS) receiver. In such a configuration, the control assembly will
receive
geographical position information from the GPS receiver, thereby facilitating
position
determination of the air cart 12. As such, the control assembly may implement
"Smart Farming" whereby the metering system 32 is controlled based on the
geographical position of the metering system 32, air cart 12, and/or implement
10.
[0024] FIG. 2 is a schematic diagram of exemplary metering system which may
be
employed within the air cart of FIG. 1. As illustrated, the air source 34 is
coupled to a
conduit 38 configured to enable air 40 to flow past the metering system 32. In
other
embodiments, the conduit 38 may include multiple conduit sections with one
conduit
section coupling the air source 34 to the top of the metering system 32 and
another
conduit section coupling the bottom of the metering system 32 to the
implement. In
such a configuration, air 40 flows through the metering system 32, from top to
bottom. The air 40 enters the metering system 32, combines with the metered
product, and exits the metering system 32 as a mixture of product and air.
[0025] The air source 34 may be a pump or blower powered by an electric or
hydraulic motor, for example. Flowable particulate material 42 (e.g., seeds,
fertilizer,
etc.) within the storage tank 26 flows by gravity into the metering system 32.
The
metering system 32 includes a meter roller 44. However, in certain
embodiments,
more than one meter roller 44 may be configured to regulate the flow of
material 42
into the air flow 40. In certain embodiments, the metering system 32 may
include
multiple meter rollers 44 disposed adjacent to one another along a
longitudinal axis of
the rollers 44, or in other embodiments, the meter rollers 44 may be
positioned so
their rotational axes are parallel to one another. For example, certain
metering
systems 32 include eight meter rollers 44 arrange in a linear configuration.
Such
systems 32 are known as "8-run" metering assemblies. However, alternative
embodiments may include more or fewer meter rollers 44, e.g., 5, 6, 7, 8, 9,
or more.
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[0026] Each meter roller 44 includes an interior passage/cavity 46
configured to
receive a shaft that drives the meter roller 44 to rotate. In the illustrated
embodiment,
the cavity 46 has a hexagonal cross section. However, alternative embodiments
may
include various other cavity configurations (e.g., triangular, square, keyed,
splined,
etc.). The shaft is coupled to a drive unit, such as an electric or hydraulic
motor,
configured to rotate the meter rollers 44. Alternatively, in certain
embodiments, the
meter rollers 44 may be coupled to a wheel by a gear assembly such that
rotation of
the wheel drives the meter rollers to rotate. Such a configuration will
automatically
vary the rotation rate of the meter rollers based on the speed of the air
cart.
[0027] Each meter roller 44 also includes multiple ridges 48 and flutes 50.
The
number and geometry of the flutes 50 are particularly configured to
accommodate the
material 42 being distributed. The illustrated embodiment includes six flutes
50 and a
corresponding number of ridges 48. Alternative embodiments may include more or
fewer flutes 50 and/or ridges 48. For example, the meter roller 44 may include
2, 4, 6,
8, 10, 12, 14, 16, 18, 20, or more flutes 50 and/or ridges 48. In addition,
the depth of
the flutes 50 and/or the height of the ridges 48 are configured to accommodate
the
material 42 within the storage tank 26. For example, a meter roller 44 having
deeper
flutes 50 and fewer ridges 48 may be employed for larger seeds, while a meter
roller
44 having shallower flutes 50 and more ridges 48 may be employed for smaller
seeds.
Other parameters such as flute pitch (i.e., rotation relative to a
longitudinal axis) and
flute angle (i.e., rotation relative to a radial axis) may also be varied in
alternative
embodiments. Furthermore, in certain embodiments, a meter roller 44 having
variable
geometry flutes 50 may be employed to accommodate a variety of seed sizes.
[0028] For a particular meter roller configuration, the rotation rate of
the meter
roller 44 controls the flow of material 42 into the air stream 40.
Specifically, as the
meter roller 44 rotates, material is transferred through an opening 52 in the
metering
system 32 into the conduit 38. The material then mixes with air from the air
source
34, thereby forming an air/material mixture 54. The mixture then flows to the
row
units of the implement 10 via the pneumatic conduits, where the seeds and/or
fertilizer
are deposited within the soil. In the present embodiment, the metering system
32 may
be deactivated by stopping rotation of the meter rollers 44, thereby
substantially
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blocking the flow of material through the opening 52. Conversely, the metering
system 32 may be activated by engaging rotation of the meter rollers 44. In
this
manner, product flow to the row units may be temporarily suspending while the
ground engaging tools are in a non-working position or when product flow from
a
particular meter roller 44 is undesirable.
[0029] FIG. 3 is a perspective view of a metering system 32 with meter
rollers
having a parallel rotational axis. As illustrated, the metering system 32
includes
multiple meter boxes 56 positioned adjacent to one another. In this
embodiment,
eight meter boxes 56 are included in the metering system 32. However, in other
embodiments, 1, 2, 3, 4, 5, 6, 7, 8, 9, or more meter boxes 56 may be employed
within
the metering system 32. The meter boxes 56 enable product to flow directly to
a
meter roller (not shown) disposed inside each meter box. Furthermore, a
primary
distribution hose 58 and a secondary distribution hose 60 extend through each
of the
meter boxes 56 in a direction generally parallel to the rotational axes of the
meter
rollers. In alternative embodiments, the distribution hoses 58 and 60 may
extend
through the meter boxes 56 in a direction generally perpendicular to the
rotational
axes of the meter rollers.
[0030] The distribution hoses 58 and 60 facilitate product flow to the
ground
engaging tools. In addition, the distribution hoses 58 and 60 enable product
to be
combined or isolated before flowing to the ground engaging tools. For example,
product from one or more meter boxes 56 may flow into the distribution hoses
58,
while product from other meter boxes 56 may flow into the distribution hoses
60. In
certain embodiments, product from a separate metering system may be delivered
to
the hoses 58 and/or 60 before the hoses receive product from the meter boxes
56. In
this manner, multiple products may be combined within the hoses 58 and/or 60.
[0031] Each of the meter boxes 56 includes a sprocket 62 coupled to the
meter
roller (not shown). While substantially uniform sprockets 62 are employed in
the
illustrated embodiment, it should be noted that alternative embodiments may
utilize
sprockets that vary in size and/or number of teeth. As such, the rotational
speed of
each meter roller may be particularly adjusted by selecting a sprocket having
a desired
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size and/or number of teeth. In the illustrated embodiment, the meter rollers
are
disposed inside the meter boxes 56 and are driven to rotate by the sprockets
62.
Further, the meter rollers are positioned so that their rotational axes are
parallel to one
another.
[0032] In the illustrated embodiment, the metering system 32 includes a
drive
sprocket 64 and an idler sprocket 66. The drive sprocket 64, the idler
sprocket 66,
and the sprockets 62 include teeth configured to interface with a chain that
drives the
sprockets 62 to rotate, thereby rotating the meter rollers. However, it should
be
appreciated that a pulley/belt arrangement may be employed in alternative
embodiments to drive the meter rollers to rotate. In certain embodiments, the
chain
may be routed from the drive sprocket 64 over the top of an adjacent sprocket
62,
under the bottom of a subsequent sprocket 62, and then over the top of the
next
sprocket 62, and so on, along the length of the metering system 32. The chain
may
then extend across the top of the idler sprocket 66, and loop around to the
drive
sprocket 64. In such a configuration, when the drive sprocket 64 is driven to
rotate by
a drive unit, the chain will drive each sprocket 62 to rotate a respective
meter roller.
The drive unit may be stopped or started to cause each individual sprocket 62
to
rotate. Further, a clutch, such as an electrical or a mechanical clutch, may
be
positioned between each sprocket 62 and a respective meter roller. The clutch
may
enable each meter roller to be selectively engaged or disengaged, thereby
enabling
individual control of each meter roller. Furthermore, the clutches may be
configured
to provide controlled slippage, thereby enabling the meter rollers to operate
at varying
speeds relative to one another.
[0033] Each of the meter boxes 56 includes a selection bar configured to
enable
product to be distributed into either distribution hose 58 or 60. Furthermore,
a tube
adjustment bar 68 extends out from the metering system 32 and is configured to
control the position of the selection bars. For example, in one position, the
tube
adjustment bar 68 enables product metered in the meter boxes 56 to flow into
the
primary distribution hoses 58, while in another position, the tube adjustment
bar 68
enables product metered in the meter boxes 56 to flow into the secondary
distribution
hoses 60.
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[0034] FIG. 4 is a cross-sectional side view of a meter box 70 of the
metering
system of FIG. 3. The meter box 70 includes a roller section 72 and a
distribution
section 74. Product enters the roller section 72 and is directed toward the
meter roller
44 via a sloped member 76. The meter roller 44 is positioned within an opening
78 in
the meter box 70, and the meter roller 44 is secured in place and driven by a
drive
shaft inserted through the cavity 46. The drive shaft, in turn, is connected
to the
sprocket 62, thereby driving the meter roller 44 to rotate as the sprocket is
driven by
the chain.
[0035] The distribution section 74 includes a tube selection assembly 80 to
determine whether product flows into the primary distribution hose 58 or the
secondary distribution hose 60. The tube selection assembly 80 includes a
selection
bar 82 attached to a hinge 84. Furthermore, the hinge 84 is coupled to the
adjustment
bar so that movement of the adjustment bar drives the selection bar 82 to
rotate in
directions depicted by arrows 86. When the selection bar 82 is in the
illustrated
position, product from the meter roller 44 flows into the primary distribution
hose 58
through an opening 88. When the selection bar 82 is rotated to the left such
that the
bar contacts the opposite side of the distribution section housing, product
from the
meter roller 44 will flow into the secondary distribution hose 60 through an
opening
90. In certain embodiments, the selection bar 82 may be positioned in a
central
position between the sides of the distribution section housing to enable
product to
flow from the meter roller 44 into both the primary distribution hose 58 and
the
secondary distribution hose 60.
100361 As illustrated by arrow 92, product enters the meter box 70 through
the top
of the roller section 72. The product is directed to the meter roller 44 via
the sloped
member 76. As the meter roller 44 rotates, product flows into the distribution
section
74. Depending on the position of the tube selection assembly 80, product will
flow to
either or both of the distribution hoses 58 and 60. Product flowing into to
the primary
distribution hose 58 along the direction 94 may combine with any other product
within the primary distribution hose 58, and the combined products will flow
toward
the implement. Likewise, product that flows into the secondary distribution
hose 60
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along the direction 96 may combine with any other product within the secondary
distribution hose 60, and the combined products will flow toward the
implement.
[0037] FIG. 5 is a schematic diagram of another embodiment of a metering
system
98. As illustrated, a drive unit 100 is coupled to each meter box 56.The drive
units
100 are configured to individually control the rotation of each meter roller.
As will be
appreciated, the drive units 100 may be any suitable device that may drive the
meter
rollers to rotate, such as an electric or hydraulic motor, for example. A
controller 102
is coupled to the drive units 100 via a wiring assembly 104. The controller
102 is
configured to send signals to the drive units 100 to selectively engage and
disengage
rotation of the meter rollers, and to control the speed of meter roller
rotation. In such
a configuration, the meter rollers may be individually controlled to enable
selective
meter roller rotation and speed control.
[0038] FIG. 6 is a top view of an embodiment of a metering system having a
meter
roller sleeve assembly 108. In the illustrated embodiment, meter rollers 44
are
disposed within meter roller sleeves 108. The meter roller sleeves 108 are cup
shaped
or cylindrical, and are configured to surround at least a portion the meter
rollers 44.
In certain embodiments, the meter roller sleeves 108 may be configured to
surround
an entire meter roller. As discussed in detail below, the meter roller sleeves
108 may
assist in controlling the flow rate of product from the meter rollers 44.
Furthermore, a
sleeve adjustment bar 110 is coupled to each of the meter roller sleeves 108
via sleeve
adjustment assemblies 112.
[0039] In addition, bar adaptors 114 are coupled to each end of the sleeve
adjustment bar 110. The sleeve adjustment bar 110 and/or the bar adaptors 114
may
be adjusted to cause the sleeves 108 to expose more or less of the surface
area of the
meter rollers 44. As more of the surface of the meter rollers 44 is exposed, a
greater
amount of product may be distributed by the meter rollers 44. Conversely, as
less of
the surface of the meter rollers 44 is exposed, a smaller amount of product
may be
distributed by the meter rollers 44. Thus, the amount of product distributed
by the
meter rollers 44 may be controlled by adjusting the position of the meter
rollers
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sleeves 108. As depicted, the meter roller sleeves 108 expose a portion of the
meter
rollers 44 having a length 116.
[0040] As will be appreciated, certain products may be metered at a low
rate, such
as canola, for example. Consequently, meter rollers configured to dispense
such
products may be turned at a very slow rate. Unfortunately, hydraulic drive
systems
configured to rotate the meter rollers may "stall" if turned too slowly.
However, in
the illustrated embodiment, the sleeves 108 may cover a portion of the meter
roller 44,
thereby enabling the meter roller to rotate faster, while still metering the
appropriate
amount of product. The faster turn rate may substantially reduce or eliminate
the
possibility of stalling the hydraulic drive system. Other products, such as
peas or
fertilizer, may utilize a faster turn rate, so the meter roller sleeves 108
may be
positioned to cover a smaller surface area of the meter roller 44.
Furthermore, the
position of the meter roller sleeves 108 may be adjusted, either alone or in
conjunction with varying the rotational rate of the meter rollers 44, to
control product
flow rate through the metering system.
[0041] The meter roller sleeves 108 may enable a metering system to meter a
variety of products with a single meter roller configuration, thereby
obviating the
process of exchanging meter rollers when switching products. For example, an
operator may select a particular meter roller configuration (e.g., having a
desired flute
depth, number of flutes, etc.) to facilitate accurate metering of a particular
product.
The operator may then remove the current meter roller, and install a new meter
roller
having the desired properties. Due to the duration of the meter roller
replacement
process, the implement will spend less time in the field, thereby reducing
seeding
efficiency. In contrast, because the illustrated embodiment facilitates
varying product
flow rate by adjusting the position of the sleeves 108 and/or the speed of the
meter
rollers 44, a particular meter roller configuration may be utilized to meter a
variety of
products, thereby increasing the efficiency of seeding operations.
[0042] In addition to controlling the collective group of meter roller
sleeves 108,
individual meter roller sleeves 108 may be independently adjusted. For
example, the
sleeve adjustment assembly 112 of a particular meter roller sleeve 108 may be
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adjusted to cause the meter roller sleeve 108 to cover more or less of the
corresponding meter roller 44 than the other meter roller sleeves 108.
Specifically,
each meter roller sleeve 108 may be adjusted by rotating the meter roller
sleeve 108
about a threaded rod of the sleeve adjustment assembly 112, thereby extending
or
retracting the sleeve 108. Alternatively, the meter roller sleeve 108 may be
adjusted
by rotating an adjustment bolt of the sleeve adjustment assembly 112. Such
fine
tuning may be used to adjust product flow rate to particular groups of row
units,
thereby compensating for variations in the number of row units per group.
[0043] FIG. 7 is a top view of the meter roller sleeve assembly 106 of FIG.
6,
illustrating meter roller sleeve adjustment. As illustrated, the sleeve
adjustment bar
110 and/or the bar adaptors 114 are coupled to an actuation unit 118. The
actuation
unit 118 is configured to move the sleeve adjustment bar 110 and/or the bar
adaptors
114 relative to the meter rollers 44. The actuation unit 118 may be operated
via
hydraulics, a solenoid, an electromechanical device, or any other type of
suitable
device configured to provide the desired actuation. Furthermore, the actuation
unit
118 enables the meter roller sleeves 108 to be adjusted (i.e., moved back and
forth)
during operation, such as while planting or fertilizing a field. Specifically,
the sleeve
adjustment bar 110 may move to expose a length 120 of the meter rollers 44. As
will
be appreciated, the sleeve adjustment bar 110 may be moved automatically, such
as
via the actuation unit 118, or manually. When the sleeve adjustment bar 110 is
moved, each of the sleeves 108 are moved with the bar 110.
[0044] Furthermore, the individual sleeves 108 may be adjusted such that
different
sleeves 108 cover different portions of the meter rollers 44. For example, one
sleeve
108 may be adjusted via an adjustment assembly 122, thereby causing the sleeve
108
to expose a portion of the meter roller 44 having a length 124. As
illustrated, the
length 124 is smaller than the length 120. However, by adjusting the
adjustment
assembly 122 in an opposite direction, the length 124 may be greater than the
length
120. Another adjustment assembly 126 may be adjusted to cause the sleeve 108
to
expose a length 128 of the meter roller 44. The length 128 is smaller than the
length
124 and the length 120. However, as previously discussed, the adjustment
assembly
126 may be adjusted to cause the length 128 to be greater than the length 120
and/or
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the length 124. Further, any of the adjustment assemblies 112 may be adjusted
to
cause the sleeves 108 to cover a different portion of a respective meter
roller 44.
Such adjustments may be made manually, or via individual actuation units that
may
be attached to each meter roller sleeve 108 to individually fine tune the
position of the
meter roller sleeves 108. Each meter roller sleeve 108 may also be used to
completely
block product flow to a respective meter roller 44 by completely covering the
meter
roller 44. Such a complete product shut off may also be performed by either an
actuator controlled or manual controlled arrangement.
[0045] As discussed in detail below, the meter roller sleeve assembly 106
may
employ meter rollers 44 having variable geometry flutes. Such meter rollers 44
may
provide increasing displacement along the length of the meter roller 44.
Therefore,
the product flow rate may vary non-linearly as the meter roller sleeve 108
covers
varying portions of the meter roller 44.
[0046] FIG. 8 is a perspective view of a meter roller 130 having variable
geometry
flutes. The meter roller 130 includes alternating flutes 132 and ridges 134.
As
illustrated, an aggregate cross sectional area of the flutes increases along a
longitudinal axis of the meter roller, thereby providing a meter roller having
a
displacement that varies with axial position. In the illustrated embodiment,
each flute
twists about the longitudinal axis as the flute extends between first and
second
longitudinal ends of the meter roller. At a first end 136, the flutes 132 have
a width
138, while the ridges 134 have a width 140. Further, at a second end 142, the
flutes
132 have a width 144, while the ridges 134 have a width 146. As illustrated,
the
width 138 of the flutes 132 at the first end 136 is smaller than the width 144
of the
flutes 132 at the second end 142. Conversely, the width 140 of the ridges 134
at the
first end 136 is greater than the width 146 of the ridges 134 at the second
end 142.
[0047] In the illustrated embodiment, an angle 148 between the flutes 132
and the
first end 136 is less than 90 degrees. However, it should be appreciated that
in
alternative embodiments, the angle 148 may be equal to or greater than 90
degrees.
The flutes 132 have a generally arcuate profile, reaching a depth 150.
However, in
other embodiments, the flute profile may form other shapes, such as square,
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triangular, circular, etc. Thus, as illustrated, the meter roller 130 has
flutes 132 that
expand in width and depth as they extend from the first end 136 to the second
end
142. Furthermore, the meter roller 130 has a longitudinal passage152 extending
between the ends 136 and 142. The passage 152 enables a drive shaft to be
inserted
therein to drive the meter roller 130. Although the opening 152 is depicted
with a
hexagonal shape, any other shapes may be used, such as triangular, square,
pentagonal, etc., may be employed in alternative embodiments.
[0048] As will be appreciated, the illustrated meter roller 130 with
variable
geometry flutes may be combined with a meter roller sleeve as described
previously.
As such, the meter roller sleeve may enable only a portion of the meter roller
130 to
meter product. In such a configuration, the meter roller may be adjusted to
efficiently
deliver various product sizes. Furthermore, a combination of a meter roller
sleeve and
the meter roller 130 may enable further control of metering properties, such
as
metering rates and operating rotations per minute.
[0049] FIG. 9 is a cross-sectional side view of the meter roller 130 of
FIG. 8, taken
along line 9-9. The meter roller 130 has a surface area 154 in a plane
generally
parallel to the first end. The surface area 154 is the area of the depicted
circular cross-
section that excludes the aggregate area of the flutes 132 (i.e., the
collective sum of
each individual area 156 of the flutes 132), and the area of the passage 152.
Furthermore, the area 156 of each flute 132 has a width 158 and a depth 160.
The
depth 160 of each flute 132 varies across the width 158 to create a generally
arcuate
shape. It should be noted that the width of each ridge 134 is greater than the
width
158 of each flute 132.
[0050] FIG. 10 is a cross-sectional side view of the meter roller 130 of
FIG. 8,
taken along line 10-10. The meter roller 130 has a surface area 162. The
surface area
162 is the area of the depicted circular cross-section that excludes the
aggregate area
of the flutes 132 (i.e., the collective sum of each area 164 of the flutes
132), and the
area of the passage 152. Furthermore, the area 164 of each flute 132 has a
width 166
and a depth 168. The depth 168 of each flute 132 varies across the width 166
to
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create a generally arcuate shape. It should be noted that each of the ridges
134 has a
smaller width than the width 166 of each flute 132.
[0051] As will be appreciated, the surface area 162 of the cross-section of
FIG. 10
is smaller than the surface area 154 of the cross-section of FIG. 9. In
addition, the
cross-sectional surface area of the meter roller 130 continuously decreases
from the
first end to the second end of the meter roller 130. Furthermore, it is noted
that the
aggregate area of the flutes 132 (i.e., the collective sum of each individual
area 164 of
the flutes 132) of FIG. 10 is greater than the aggregate area of the flutes
132 of FIG. 9
(i.e., the collective sum of each individual area 156 of the flutes 132). As
such, the
cross-sectional aggregate area of the flutes 132 continuously increases from
the first
end to the second end of the meter roller 130. Furthermore, the width 166 and
the
depth 168 of each flute 132 in FIG. 10 is greater than the width 158 and the
depth 160
of each flute 132 in FIG. 9. Thus, the width and the depth of the flutes 132
continuously increases from the first end to the second end of the meter
roller 130.
[0052] While only certain features of the invention have been illustrated
and
described herein, many modifications and changes will occur to those skilled
in the
art. While embodiments of the invention have been described in the detailed
description, the scope of the claims should not be limited by the embodiments
set
forth in the examples, but should be given the broadest interpretation
consistent with
the description as a whole.
