Note: Descriptions are shown in the official language in which they were submitted.
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"CHAFF SPREADER FOR COMBINE HARVESTER"
BACKGROUNV OF THE INVENTION
This invention relates to apparatus for spreading
chaff discharged from a combine harvesting apparatus or
similar grain threshing machine. Many combines include a
cleaning shoe at which chaff is discharged at a position
spaced from the discharge of straw. Many different types
of apparatus have been proposed for use at the straw dis-
charge of such a combine for chopping the straw and spread-
ing it relative to the rear of the combine. One class of
such straw spreaders includes rotating blades which act to
chop the straw and at the same time discharge it radially.
However these apparatus are unsuitable for use in
spreading chaff discharged from the cleaning shoe and have
never been used in the area of the chaff discharge. General-
ly chaff has been allowed to discharge directly behind the
combine and attention has only been applied to the straw
discharge with devices available to chop and spread the
straw or to swath the straw for later collection.
SUMMARY OF THE INVENTION
It is one object of the invention therefore to
provide a chaff spreading apparatus for a combine which is
simple and can be readily fixed to a combine for spreading
the chaff to either side of the combine.
The invention therefore according to a first as-
pect provides a chaff spreading apparatus for a grain
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threshing machine having a cleaning shoe from which chaff
is discharged, the apparatus comprising a housing in the
form of a flat substantially horizontal plate and walls
upstanding from the plate, means for attaching the housing
to the threshing machine below the cleaning shoe to receive
chaff therefrom, blade means, means mounting the blade means
- on the housing for rotation relative to the housing in a
plane parallèl thereto about an axis at right angles
thereto to eject the chaff from the housing and direction-
al discharge means defined by said upstanding walls of the
housing and arranged to direct the chaff from the housing
to at least one side of the threshing machine.
It is one advantage of the invention that the
apparatus allows chaff to be spread evenly across the
field which reduces or eliminates the problems of uneven
tillage depth and depth of seeding and the yellow strips
of crop usually associated with stubble crops due to lack
of nitrogen.
A further advantage of the invention that there
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can be provided two fans each ejecting through a direction-
al discharge nozzle to a respective side of the combine or
grain threshing machine thus allowing the apparatus to
spread the chaff to both sides of the machine over a wide
area.
It is a yet further advantage of the invention
that it can be used to spread the chaff independently of
whether the straw is chopped and spread or is swathed and
independently of whether apparatus for such use is provided
on the combine.
It is a yet further advantage of the invention
that the fans can include slightly curved blades which act
to develop suction to draw the chaff into the blades for
ejectiOn radially of the blades. In view of the low speeds
and low suction required the suction does not interfere
with air currents within the combine and thus does not
affect the efficiency or capacity of the combine.
Itis a still further advantage of the invention
that it comprises a simple flat base with housings defined
around the fans and providing any directional discharge
nozzles defined by upstanding walls from the flat base.
With the foregoing in view, and other advantages
as will become apparent to those skilled in the art to
which this invention relates as this specification proceeds,
the invention is herein described by reference to the ac-
companying drawings forming a part hereof, which includes
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a description of the best mode known to the applicant and
of the preferred typical embodiment of the principles of
the present invention, in which:
DESCRIPTION OF THE DRAWINGS
Figure 1 is an isometric view of a chaff spread-
ing appratus according to the invention.
Figure 2 is a side elevational view of the ap-
paratus of Figure 1 attached to a combine.
Figure 3 is an exploded isometric view of the
apparatus of Figure 1.
Figure 4 is a schematic side elevation of a com-
bine incorporating the apparatus.
In the drawings like characters of reference
indicate corresponding parts in the different figures.
DETAILED DESCRIPTION
Referring generally to Figures 1, 2 and 3, the
chaff spreading apparatus comprises a frame 10 of welded
angle iron, tubular steel or other suitable material, form-
ing a rectangular structure with a cross member 1l extend-
ing from one side to the other. On top of the frame 10
is supported a flat sheet 12 of mild steel with turned down
edges to match the edges of the frame 10. Upstanding straps,
hangers or supports 13 are provided at the rear edge of
the frame 10 and forwardly extending tubular, angle iron
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or other suitable supports 14 are attached to the front
edge of the frame 10 for supporting the apparatus on the
combine as shown in Figures 2 and 4 and explained in fur
ther detail hereinafter.
The cross member 11 includes downwardly depend-
ing extensions 111 which provide bushings 112 for support-
ing a shaft 113 and pulley wheel 114. The shaft 113 ex-
tends horizontally with the pulley 114 projecting from one
or both sides of the frame 10. The cross member 11 also
carries bushings 115 which are arranged in two pairs so
as to support axles 116 which extend vertically upwardly
through holes provided in the plate 12. Cooperating bevel
gears 117 are arranged to communicate drive from the
pulley 114 through shaft 113 to the shafts 116 whereby they
are driven in synchronism.
Upon each of the shafts 116 is mounted a fan
15 comprising a central casting 151 which surrounds the
shaft 116 and incorporates means (not shown) for securing
the casting to the shaft and portions extending mutually
at right angles for supporting four blades 152. Each
blade i5 secured to the casting by screws, bolts or rivets
and extends straight out from the casting so that the
four blades lie mutually at right angles. The upper sur-
face 153 of each of the blades is bent forwardly out of
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the plane of the blade so that as the fan is rotated the
portion 153 tends to develop a downward suction with the
air drawn into the fan being ejected radially of the
blades 152.
It will be noted that as viewed from the rear
the lefthand shaft 116 rotates clockwise and the right-
hand shaft rotates counterclockwise in view of the arrange-
ment of the bevel gears 117. The fans 15 are positioned
on the shafts 116 such that the blades slightly intersect
in their motion and such that they rotate slightly out of
phase to avoid contact between the blades. In this way
the blades sweep the upper surface of the plate 12 with
no dead space between the blades.
A housing is defined around the fans 15 by two
upstanding walls 16 and 17 each of which is formed by a
curved sheet having a small flange at right angles and
arranged at the base for securing the wall to the sheet
12. Generally the walls define two circular housings sur-
rounding the tips of the blades 152 with a space interme-
diate the two fans 15 to allow the blades to intersect as
explained previously. The rear wall 16 extends from the
portion surrounding the respective Ean substantially
tangentially to the fan so as to define one side of a
directional discharge nozzle 161. The other side of the
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nozzle 161 is defined by a portion of the wall 17 parallel
to the tangential portion of the wall 16 and extending
outwardly from the circle defined by the tips of the blades
152. Each of the directional discharge nozzles 161, there--
fore, directs material or air carried by the fans 15 to the
sides of the apparatus and prevents or substantially pre-
vents material from being ejected forwardly or rearwardly
of the apparatus.
As can be best seen from Figure 2, the rear
wall 16 is substantially higher than the front wall 17
and cooperates with a curtain 18 which extends downwardly
from the body of the combine so that wa].l 16 and the cur-
tain 18 act to confine chaff ejected from the combine and
directed onto the fans 15 between the walls 16 and 17.
This is aided by the suction developed by the fans 15 A
triangular upstanding portion 171 bridges the portion on
the wall 17 between the two fans so as to direct material
falling outside the scope of the fan blades into the fan
blades.
A pair of bumper straps 19 is provided on the
frame 10 depending from the rear of the sides to provide
protection for the apparatus both in use and during trans-
port.
In use of the apparatus and as shown in Figures
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2 and 4, the apparatus is attached by the straps, hangers
or supports 13 and by the member 14 to the body of the com-
bine. The straps, hangers or supports 13 are attached to
the body in the area beneath the straw walkers and the
members 14 are attached at the rear of the cleaning shoe
area so that the fan housings and fans are positioned
generally rearwardly and beneath the outlet of the clean-
ing shoe sche~atically indicated at 20. The straw walkers
are schematically indicated at 21 with a straw chopping
device indicated schematically at 22. The remainder of
the combine shown in Figure 4 will not be described as
it is of conventional construction.
The pulley 114 is driven via a belt 115 by a
pulley 23 mounted upon the return (tailings) auger shaft.
Tensioning of the belt 115 is provided by a pair of pulleys
116, 117 with the latter mounted on the frame of the com-
bine adjacent the auger and with the former mounted upon a
strap 118 pivotally mounted relative to the pulley 117 and
biased in a belt tensioning direction by a spring 119.
The sizes of the pulleys 114 and 23 are chosen such that
the fans 15 are driven at a speed of the order of 250 rpm.
This relatively slow speed provides sufficient suction to
draw chaff discharges from the cleaning shoe 20 into the
fans 15 while avoiding excessive air streams which inter-
fere with the air streams within the combine and thus with
the separation of the chaff from the grain. The rear wall
16, the curtain 18 and the front wall 17 coact to direct
most of the chaff discharged from the shoe 20 into the fans
15 from which position the chaff is directed radially of
the fan blades through the directional discharge nozzles
161 and thus to the sides of the spreader apparatus. The
apparatus effectively prevents chaff from discharging rear-
wardly of the shoe 20 to ensure a even spread of the chaff
across the field from the discharge nozzles 161.
The drive for the pulley 114 may in an alterna-
tive arrangment (not shown) be taken from the rear straw
walker crank with suitable belt tensioning arrangment being
provided similar to that shown. In either arrangment the
drive to the chaff spreader apparatus is inde?endent of
the drive to the straw chopper 22 and to the drive to a
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straw spreader apparatus schematically indicated at 23. In
this way the chaff can be spread independently of the re-
quirement of the operative to chop and spread the straw or
to swath the straw.
In order to accommodate different processing con-
ditions of the combine, the mounting brackets 13 and 14 may
be provided with means (not shown) for adjustably mounting
the apparatus on the body of the combine so that the posi-
tion of the fans relative to the discharge of the shoe 20
can be adjusted to maximize the collection and spreading of
the chaff.
Since various modifications can be made in my in-
vention as hereinabove described, and many apparently wide-
ly different embodiments of same made within the spirit and
scope of the claims without departing from such spirit and
scope, lt is intended that all matter contained in the
accompanying specification shall be interpreted as illustra-
tive only and not in a limiting sense.
