Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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DISCLOSURE
This invention relates to air seeders generally used
for inserting fertilizer or seed into agricultural fields.
More particularly, this invention relates to a metering
auger/chemical applicator system which is attached directly to
an air seeder.
BACRGROZTND
Farmers are continually seeking methods that allow
them to farm more efficiently. They are also concerned about
disposing of treated seed which can create an environmental
hazard to animals.
It is an object of present invention to provide a
highly cost-effective, low maintenance and highly reliable
liquid application unit for use on air seeders to provide
farmers with the ability to apply liquid substances to
particulate matter only as it is being consumed for insertion
into the soil.
It is also an object of the present invention to
have an effective system which compensates for instantaneous
changes in material application rate, to keep the amount of
seed treatment per bushel of grain constant.
It is also an object of the present invention to
provide a system or delivery unit which allows for variances
in ground speed in order that the rate of product metered per
hour changes accordingly.
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SUNIlKARY OF THE INVENTION
The inventors of the present invention have found
that a two-pitch or two-diameter metering screw is an
effective way to accurately meter, mix seed and liquid
treatment and to discharge material into an air stream of an
air seeder. A sump is located and attached to the bottom of
the bins of the air seeder cart. The area of the sump is
much wider than the width taken up by the flighting. This
minimizes the amount of drag on the metering screw and
allows particulate to flow around the screw to ensure
complete filling of the flighting. In a preferred
embodiment, the flighting located in the sump before the
downstream orifice has a smaller pitch and is of smaller
diameter than the flighting which is located after the
downstream orifice. This ensures that the larger flighting
cannot be a bottleneck in the metering system and will also
provide for good mixing action for the seed and liquid seed
treatment.
In accordance with one aspect of the present
invention, there is provided an improved metering auger
assembly for applying a liquid to particulate materials from
an air seeder bin, said assembly including: an auger, a sump
and a downstream housing fixedly attached to said sump; said
downstream housing further including a liquid chemical
injection means adapted in operation to spray liquid
pesticides or herbicides on particulate matter; said sump
being in open communication with particulate within said air
seeder bins; and said downstream housing including a
discharge port at one end remote from said sump; the
improvement being a first portion of said auger is adapted
to rotate within said sump and a second portion is adapted
to rotate within said downstream housing; wherein, in
operation, said first portion of said auger has less volume
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between adjacent pitches of flighting than said second
portion.
In accordance with a second aspect of the present
invention, there is provided a method of applying a liquid
to particulate materials from a hopper of an air seeder bin,
the method comprising the steps of: a) directing seed from
the hopper of the air seeder bin into a sump; b) moving seed
through said sump with an auger comprising flighting of a
pitch and diameter providing a first volume between adjacent
pitches of flighting; c) moving said seed within a
downstream housing with an auger comprising flighting of a
pitch and diameter providing a second volume between
adjacent pitches of flighting, wherein the second volume is
greater than the first volume; d) injecting liquid chemical
into said downstream housing such that rotational movement
of said auger causes complete coverage of seed; e)
discharging coated seed from said housing into a discharge
duct receiving air from a blower fan; and f) blowing said
seed through a plurality of ducts to soil engaging
implements.
In accordance with a third aspect of the present
invention, there is provided a system attached to an air
seeder for applying liquids to particulate materials
including: a) a metering screw housing capable of receiving
particulate materials from an air seeder bin; b) a tank for
holding said liquids; c) at least one liquid injection port
located in said metering screw housing for receiving and
dispersing said liquids; d) a metering screw assembly
rotatable within said metering screw housing and capable of
accurately metering said particulate materials into transfer
ducts used to convey said particulate materials to an
implement delivering said particulate material into or onto
an agricultural field; and e) a liquid metering pump in
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direct communication with said metering screw assembly, said
liquid metering pump capable of receiving said liquid from
said holding tank and delivering said liquid to said liquid
injection port wherein metering pump output varies
proportionally with a change in rotational speed of said
metering screw assembly.
The invention includes a metering screw assembly,
a metering screw housing, a liquid metering pump, at least
one liquid treatment injection port and a liquid holding
tank all attached to the air seeder. The metering screw
assembly includes flighting attached to shafting such that
the shafting extends past both ends of the screw flighting.
The liquid metering pump communicates directly with the
metering screw assembly to instantaneously adjust the output
of the pump as to the rotational speed of the metering
screw.
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A sheave is placed on one end of the shafting
supporting the flighting. A driven sheave is either placed on
or attached directly or indirectly to the input shaft of the
metering pump, depending on the location of the pump. The
drive and driven sheaves are connected by an endless belt or
chain. In a preferred embodiment, the sheaves and belt are
notched to provide positive drive.
A holding tank contains one or more liquid chemicals
and a tubular line connects the holding tank to the input port
of the pump. The output of the pump is connected by a tubular
line to the injection port(s) located on the housing
downstream of the sump. In a preferred embodiment, the
injection port(s) is(are) located just downstream of where the
transfer tube portion of the metering screw housing and the
inner sump wall connect.
On the bottom of the sump is located a removable
cover which, once removed, allows complete emptying of the air
seeder bin. The sump also has openings on both ends for the
metering screw. The diameter of the hole in the outboard end
of the sump is slightly larger than the diameter of the
metering screw shaft. On the inboard end of the sump, the
strategically sized hole acts as an orifice and interacts with
a metering screw to produce consistent and predictable
metering.
One or more injection port(s) is(are) located on the
transfer tube downstream of the orifice located in the sump.
Injectors are typically nozzles for dispersing liquid over a
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large area on the particulate materials as they pass. The
particulate material is further acted upon by the rotation and
translation of the metering screw which further assists to
distribute the liquid more uniformly over the outer surfaces
of the seed or other treated particles. When the particulate
material exits the metering assembly it has the liquid
treatment efficiently and uniformly applied to the particulate
material so that no further mixing action is required although
more may occur in the air stream.
In normal operation, the metering assembly moves the
treated material into the transfer ducts that contain a high-
speed air stream. The air stream carries the treated material
away from the air seeder bins to be deposited either in or on
top of the soil. In a preferred embodiment, the metering pump
is a positive displacement piston pump and is connected by
belts and sheaves to communicate with a metering screw. For a
given product, the output of the metering system increases as
the rotation speed of the metering screw increases, as does
the output of the pump. Normally, the particulate requires a
specific amount of liquid treatment per pound of material.
The output per revolution of the pump can be varied by
changing the stroke that the piston displaces. This allows
the operator to vary the output of the metering pump to match
the particular requirements of different treatments and
materials.
Therefore this invention seeks to provide an
improved metering auger assembly for use with an air seeder
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cart; said assembly including an auger, a sump and a
downstream housing fixedly attached to said sump; said
downstream housing further including a liquid chemical
injection means adapted in operation to spray liquid
pesticides or herbicides on particulate matter; said sump
being in open communication with particulate within said air
seeder cart, and said downstream housing including a discharge
port at one end remote from said sump; the improvement being a
first portion of said auger is adapted to rotate within said
sump and the second portion is adapted to rotate within said
downstream housing; wherein, in operation, said first portion
having a lesser volume available between adjacent pitches of
the flighting for each revolution of said auger than said
second portion.
This invention fuzther seeks to provide a system
attached to an air seeder for applying liquids to particulate
materials including: a) a metering screw housing capable of
receiving particulate materials from an air seeder bin, b) a
tank for holding said liquids, c) at least one liquid
injection port located in said metering screw housing for
receiving and dispersing said liquids, d) a metering screw
assembly rotatable within said metering screw housing and
capable of accurately metering said particulate materials into
transfer ducts used to convey said particulate materials to an
implement delivering said particulate material into or onto an
agricultural field, e) a liquid metering pump in direct
communication with said metering screw assembly, said liquid
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metering pump capable of receiving said liquid from said
holding tank and delivering said liquid to said liquid
injection port where said metering pump's output varies
proportionally with a change in the rotational speed of said
metering screw assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more accurately described in
conjunction with the following drawings wherein:
Fig. 1 is an exploded view of the basic auger system
without chemical injection;
Fig. 2 is a perspective cut away view of the auger
without the chemical injection system;
Fig. 3 is a perspective view of the auger, along
with the pump, drive sheaves and injector;
Fig. 4 is a side view of the present invention;
Fig. 5 is a top view of the present invention; and
Fig. 6 is a side view of the holding tank.
DETAILED DESCRIPTION OF THE INVENTION
In Figs. 1 and 2 there is a downstream metering
housing or transfer tube 1. It is connected to a sump 2 which
has a discharge orifice 3. The downstream metering housing 1
is equipped with a discharge port 4. In this embodiment a
pressurization port 5 is also used.
The metering screw assembly is shown generally as 6.
It has a first section of flighting 7 which, in this
embodiment, is of lesser diameter and generally of smaller
pitch. This portion of the metering auger is adapted to
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rotate within the sump 3 and carries a smaller volume per each
revolution. Located on the shaft 14 is a downstream portion
of the metering auger 8 which, in this embodiment, has a wider
diameter flighting as well as larger pitch. However, it is to
be understood that all that is necessary for the invention is
that the downstream portion be capable of carrying a larger
volume per revolution than the upstream portion located in the
sump. This ensures that particulate material is basically
moved translationally rather than rotationally in the
downstream portion and therefore ensures that the seed and
liquid seed treatment will mix adequately.
On the downstream end of a first embodiment of the
invention is a connecting block 9 over which is placed a
gasket 10 and a bearing 11. Bolts 12 and nuts 13 secure the
bearing, gasket and connecting block to the downstream end of
the metering housing 1. Shaft 14 of the metering screw
assembly rotates with the bearings 11 at one end and 22 at the
opposite end of the sump 2.
The sump has an open top or housing inlet 15 which
is secured to the bottom of the hopper of an air seeder bin
(not shown). The sump is also equipped with a lower clean out
cover which is fastened to the bottom of the sump by means of
wing bolts 17. Both the sump and the air seeder hopper can be
completely cleaned out, when seed changeover is necessary. On
the upstream side of the sump, nuts and bolts 18, 22 and 19
secure the connecting block 20, gasket 21 and bearing 22 to
the sump.
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Fig. 2 illustrates a first embodiment of the
invention without the chemical injection apparatus. One notes
the significant difference in the size and pitch of the two
parts of auger assembly 3.
Figs. 3, 4 and 5 show a preferred embodiment of the
invention. An injection port 25 is secured just downstream of
the sump discharge orifice 3. The injection port 25, which is
a wide spread nozzle, carries liquid herbicide or pesticide
from hose 26 which is connected to pump 27. Particulate
material passing through downstream metering housing 1 is
broadly covered with such liquid such that when the seed
leaves the airstream duct 34 it is completely covered and
ready to be placed in or on the soil.
Pump 27 is a chemical pump which could be a positive
displacement piston pump. Liquid is supplied to the pump by a
hose 28 which leads from the holding tank 36 shown in Fig. 6.
Metering screw housing adapter 29 is attached to downstream
metering housing. Metering screw shaft 14 is equipped with a
driving sheave 30 which connects to a driven sheave 32 on the
liquid metering pump 27 by way of a notch belt 31. A pump
support bracket 33 is attached to metering screw housing
adapter 29.
The chemically treated seed or particulate matter is
discharged into and through air stream duct 34 which
communicates with a high speed blower fan and distributes seed
or other particulate matter to various manifolds and discharge
hoses located on a agricultural planting implement. As shown,
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most clearly in Fig. 4, a clean-out cover gasket 35 is located
between clean-out cover 16 and sump 2. The liquid chemical
holding tank 36 is secured to an air seeder (not shown) by
bracket 37. The holding tank 36 is equipped with various
valves 38 and a clean out drain 39. Normally, lower valve 38
is open and drain 39 is closed and liquid runs through tank
hose 28 to the pump 27.
With this arrangement the metering auger assembly 6
rotates proportionately to ground speed and similarly the pump
turns proportionately to the metering auger assembly 6,
although at a much quicker rate. Thus, regardless of ground
speed the correct amount of chemically covered particulate
seed is dispersed evenly to each acre of farm land.
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