Note: Descriptions are shown in the official language in which they were submitted.
CA 02357825 2001-09-27
CROP STRIPPER FOR THE CROP TRANSPORT DRAPER OF A
HEADER
This invention relates to header including a crop stripper for separating
the crop from the transport draper of a crop harvesting header.
BACKGROUND OF THE INVENTION
A header for a crop harvesting machine generally comprises a main
longitudinal support member in the form of an elongate tube which extends
across
substantially the full width of the header frame and defines a main structural
member
for the header frame. The tube carries a plurality of forwardly and downwardly
extending support beams which include a first portion extending downwardly and
a
second portion attached to a lower end of the first portion and extending
forwardly
therefrom toward a forward end of the support beams. The cutter bar is
attached to
the forward end of the support beams and is thus held thereby in a position
generally
parallel to the main support tube.
In U.S. Patents 4,956,966 issued September 1990 and 5,005,343
issued April 1991 by Patterson and assigned to the present Assignee is
disclosed a
header which utilizes two side drapers to transport the crop cut by the knife
inwardly
along the header table to a central discharge opening. The side drapers
discharge
onto a central feed draper which has a front roller just behind the knife and
a rear
roller at the feeder house of a combine harvester so as to carry the crop from
the
side drapers rearwardly into the feeder house for inlet into the combine
harvester for
processing. A rotary feed member which may carry auger flight portions is
mounted
at the discharge opening of the header above the feed draper so as to assist
in
carrying bulky crop through the discharge opening so as to be carried into the
feeder
house. The feed draper is carried on the rear roller which is attached to a
feeder
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2
house and therefore the feed draper and its associated underlying pan flex and
twist
as the header floats relative to the feeder house.
While this arrangement has achieved considerable commercial
success, it is desirable to improve the feed of the crop material from the
side drapers
into the feeder house particularly in relation to bulky crops such as soy
beans.
A subsequent U.S. Patent which is 5,454,371 issued November 1995
by Honey discloses a similar arrangement in which the crop is transferred from
the
rear end of the feed draper into a rigid fixed adapter housing which is
mounted on
the front of the feeder house and contains the rotary feed member in the form
of an
auger with conventional feeding fingers. This arrangement therefore requires
that
the header is moved forwardly relative to the feeder house so as to provide
the
space necessary for the adapter housing and its rotary feed member contained
therein.
In both patented arrangements there is significant difficulty in ensuring
that the crop is effectively stripped from the drapers for transfer from the
side
drapers onto the feed draper to move rearwardly into the feeder house.
Further commercial devices are manufactured by Deere and Company
and Agco but it is believed that there are no patents disclosing the
construction of
these devices.
While the present invention is primarily designed for use with a header
of the above type for feeding the crop into the combine harvester, the same
stripper
arrangement as described in detail hereinafter can also be used in other
arrangements where it is necessary to remove or strip crop from the end of a
draper
or conveyor.
SUMMARY OF THE INVENTION
It is one object of the present invention to provide a header in which
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3
the system for transfer of crop from the side drapers to the feeder house is
improved.
According to a first aspect of the invention there is provided a crop
harvesting header for a combine harvester comprising:
a main frame structure extending across between two ends of the
header across a width of the header for movement in a direction generally at
right
angles to the width across ground including a crop to be harvested;
a mounting assembly for carrying the main frame structure on the
combine harvester;
a crop receiving table carried on the main frame structure across the
width of the header;
a cutter bar across a front of the table carrying a cutter knife operable
for cutting the crop as the header is moved forwardly across the ground for
depositing the crop onto the table;
and a crop transport system for moving the cut crop toward a
discharge location of the header for feeding the crop into a feed opening of
the
combine harvester;
the crop transport system including:
a first side draper having an outer end guide roller at a first end
of the header, an inner end guide roller adjacent the discharge location and a
continuous draper canvas wrapped around the outer and inner guide rollers to
define
a top run of the canvas for carrying the cut crop from the knife across the
header to
a discharge end adjacent the discharge location;
a second side draper having an outer end guide roller at a
second end of the header, an inner end guide roller adjacent the discharge
location
and a continuous draper canvas wrapped around the outer and inner guide
rollers to
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4
define a top run of the canvas for carrying the cut crop from the knife across
the
header to a discharge end adjacent the discharge location;
a feed draper located at the discharge location and including a
front guide roller adjacent the cutter bar, a rear guide roller behind the
front guide
roller and a draper canvas wrapped around the front and rear guide rollers to
define
a top run of the feed draper for receiving the crop material from the
discharge ends
of the first and second side drapers and for carrying the crop material
rearwardly
toward the feed opening of the combine harvester;
a first discharge roller immediately adjacent to and parallel to
the inner end guide roller of the first side draper and arranged to receive
the crop
therefrom to pass over a peripheral surface of the first discharge roller;
a first stripper blade having a stripper edge at the peripheral
surface of the first discharge roller, the first stripper blade having a
length
substantially equal to the full length of the roller and a width to guide the
stripped
crop from the peripheral surface to the upper run of the feed draper;
a second discharge roller immediately adjacent to and parallel
to the inner end guide roller of the second side draper and arranged to
receive the
crop therefrom to pass over a peripheral surface of the second discharge
roller; and
a second stripper blade having a stripper edge at the peripheral
surface of the second discharge roller, the second stripper blade having a
length
substantially equal to the full length of the roller and a width to guide the
stripped
crop from the peripheral surface to the upper run of the feed draper.
Preferably each discharge roller has a top edge lying substantially in a
common plane with or more preferably slightly lower than the upper run of the
canvas of the respective side draper.
Preferably the feed draper has side edges each of which is located
CA 02357825 2001-09-27
inwardly of the respective discharge roller and each stripper blade is
inclined
downwardly and inwardly from the respective discharge roller so as drop the
crop
onto the upper run of the feed draper.
Preferably the side drapers each includes transverse slats and each
5 discharge roller is spaced from the respective inner guide roller by a
distance just to
clear the slats.
Preferably, according to one important aspect, the peripheral surface
of each discharge roller includes a generally cylindrical surface surrounding
an axis
of the roller with a plurality of raised projections thereon with each
projection defining
a raised portion having a greater radial distance from the axis than the
cylindrical
surface, the projections are arranged at axially spaced locations on the
cylindrical
surface leaving between the projections portions of the cylindrical surface
which are
not raised, the stripper edge of the stripper blade cooperates with the
discharge
roller having a plurality of axially spaced recesses therein with each recess
being
axially aligned with a respective one of the projections and with each recess
being
separated from the next by a portion of the stripper edge; and each recess is
shaped
such that rotation of the roller causes the corresponding projection to pass
therethrough while said portions of the stripper edge are located at said
portions of
the peripheral surface of the roller to guide the stripped crop from the
peripheral
surface to the upper run of the feed draper.
Preferably each projection is shaped in a cross-section lying in a radial
plane so as to define a leading surface, a trailing surface and an apex
surface at a
junction between the leading edge and the trailing edge and wherein the
leading
surface is shaped and arranged relative to the peripheral surface and the
stripper
blade such that, as the leading surface enters the respective recess through
an
outer surface of the blade, the leading surface defines an angle with the
outer
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6
surface of the blade which is greater than 90 degrees.
Preferably the leading surface is shaped and arranged relative to the
outer surface of the blade such that the whole or substantially the whole of
the
leading surface passes through the outer surface into the recess before the
angle
reaches ninety degrees.
Preferably the leading surface defines an angle relative to a line
intersecting the axis of the roller and the apex which is greater than 30
degrees.
Preferably the leading surface and the trailing surface are substantially
sides of a triangle having an angle therebetween greater than 60 degrees and
more
preferably of the order of 90 degrees.
Preferably there is provided a plurality of rows of projections with the
projections of each row being axially spaced and axially aligned with the
projections
of the other row or rows.
Preferably the rows are arranged axially of the roller.
Preferably each projection has axially spaced sides which are shaped
and arranged to closely match axially spaced sides of the recess such that the
projection passes through the recess with only small clearances.
Preferably the axially spaced sides of the each projection are tapered
outwardly and axially..
Preferably the leading surface and the trailing surface are substantially
sides of a triangle having an angle therebetween greater than 60 degrees.
Preferably the side drapers each includes transverse slats and each
discharge roller is spaced from the respective inner guide roller by a
distance such
that an outermost edge of the projections just clears an outermost edge of the
slats.
It is a further object of the present invention to provide an improved
header in which separation or stripping of the crop from the crop transport
draper is
CA 02357825 2001-09-27
improved.
According to a second aspect of the invention there is provided crop
harvesting header comprising:
a main frame structure extending across between two ends of the
header across a width of the header for movement in a direction generally at
right
angles to the width across ground including a crop to be harvested;
a mounting assembly for carrying the main frame;
and a crop transport system for moving the cut crop toward a
discharge location of the header including:
a crop transport member having a peripheral surface over which the
crop is carried arranged for movement of the peripheral surface in a crop
transport
direction;
the peripheral surface having a cylindrical surface from which the crop
is to be discharged;
a stripper blade having a stripper edge at the cylindrical surface to strip
the crop from the peripheral surface for discharge therefrom;
the cylindrical surface surrounding an axis with a plurality of raised
projections thereon with each projection defining a raised portion having a
greater
radial distance from the axis than the cylindrical surface,
the projections being arranged at axially spaced locations on the
cylindrical surface leaving between the projections portions of the
cylindrical surface
which are not raised,
the stripper edge of the stripper blade having a plurality of axially
spaced recesses therein with each recess being axially aligned with a
respective
one of the projections and with each recess being separated from the next by a
portion of the stripper edge;
CA 02357825 2001-09-27
each recess being shaped such that rotation of the cylindrical surface
about the axis causes the corresponding projection to pass therethrough while
said
portions of the stripper edge are located at said portions of the peripheral
surface to
guide the stripped crop from the peripheral surface.
According to a third aspect of the invention there is provided crop
harvesting header comprising:
a main frame structure extending across between two ends of the
header across a width of the header for movement in a direction generally at
right
angles to the width across ground including a crop to be harvested;
a mounting assembly for carrying the main frame;
and a crop transport system for moving the cut crop toward a
discharge location of the header including:
a draper having two end guide rollers and a continuous draper canvas
wrapped around the guide rollers to define a top run of the canvas for
carrying the
cut crop;
a discharge roller immediately adjacent to and parallel to one end
guide roller of the draper and arranged to receive the crop therefrom to pass
over a
peripheral surface of the first discharge roller;
the roller having a cylindrical surface from which the crop is to be
discharged;
a stripper blade having a stripper edge at the cylindrical surface to strip
the crop from the roller for discharge therefrom;
the cylindrical surface surrounding an axis of the roller with a plurality
of raised projections thereon with each projection defining a raised portion
having a
greater radial distance from the axis than the cylindrical surface,
the projections being arranged at axially spaced locations on the
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9
cylindrical surface leaving between the projections portions of the
cylindrical surface
which are not raised,
the stripper edge of the stripper blade having a plurality of axially
spaced recesses therein with each recess being axially aligned with a
respective
one of the projections and with each recess being separated from the next by a
portion of the stripper edge;
each recess being shaped such that rotation of the cylindrical surface
about the axis causes the corresponding projection to pass therethrough while
said
portions of the stripper edge are located at said portions of the cylindrical
surface to
guide the stripped crop from the cylindrical surface.
According to a fourth aspect of the invention there is provided a crop
harvesting header comprising:
a main frame structure extending across between two ends of the
header across a width of the header for movement in a direction generally at
right
angles to the width across ground including a crop to be harvested;
a mounting assembly for carrying the main frame;
and a crop transport system for moving the cut crop toward a
discharge location of the header including:
a draper having two end guide rollers and a continuous draper canvas
wrapped around the guide rollers to define a top run of the canvas for
carrying the
cut crop;
the canvas at one end roller having a cylindrical surface from which the
crop is to be discharged;
a stripper blade having a stripper edge at the cylindrical surface to strip
the crop from the roller for discharge therefrom;
the cylindrical surface surrounding an axis of the roller with a plurality
CA 02357825 2001-09-27
of raised projections thereon with each projection defining a raised portion
having a
greater radial distance from the axis than the cylindrical surface,
the projections being arranged at axially spaced locations on the
cylindrical surface leaving between the projections portions of the
cylindrical surface
which are not raised,
the stripper edge of the stripper blade having a plurality of axially
spaced recesses therein with each recess being axially aligned with a
respective
one of the projections and with each recess being separated from the next by a
portion of the stripper edge;
each recess being shaped such that rotation of the cylindrical surface
about the axis causes the corresponding projection to pass therethrough while
said
portions of the stripper edge are located at said portions of the cylindrical
surface to
guide the stripped crop from the cylindrical surface.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will now be described in conjunction
with the accompanying drawings in which:
Figure 1 is a top plan view of the center section only of a header
according to the present invention with a number of elements such as the reel
omitted for convenience of illustration.
Figure 2 is a cross sectional view along the lines 2-2 of the header of
Figure 1.
Figure 2A is a cross sectional view along the lines 2A-2A of the header
of Figure 1.
Figure 3 is an isometric view of the inner end of the side draper and its
associated stripper roller and stripper blade of the header of Figure 1.
Figure 4 is a cross sectional view along the lines 4-4 of Figure 2.
CA 02357825 2001-09-27
Figure 5 is a top plan view of the complete header of Figure 1 with a
number of elements such as the reel omitted for convenience of illustration.
Figure 6 is an isometric view of the center section of the header of
Figure 1 looking rearwardly toward the feeder house.
Figure 7 is a cross-sectional view similar to that of figure 4 showing a
second embodiment of stripper arrangement for separating the crop from the end
of
the side draper.
Figure 8 is a top plan view of the embodiment of Figure 7.
Figures 9 and 10 are scrap views of the roller and stripper blade of
figure 7 showing the movement of the projections relative to the stripper
blade.
Figure 11 is a cross-sectional view similar to that of figure 4 showing a
third embodiment of stripper arrangement for separating the crop from the end
of the
side draper.
Figure 12 is a top plan view of the embodiment of Figure 11.
In the drawings like characters of reference indicate corresponding
parts in the different figures.
DETAILED DESCRIPTION
The header shown in the figures comprises a main frame 10 including
a horizontal main support beam 11 extending along the length of the header
along a
first end 12 to a second end 13 of the header. The main frame includes
forwardly
extending frame members 14 at the ends of the header together with similarly
arranged frame members intermediate the width of the header. At the front end
of
the frame members is mounted a cutter bar 15 which carries a sickle knife
construction of a conventional nature. The frame 10 is attached to an adapter
structure 16 attached to the feeder house 17 of a combine harvester 18.
The header includes a crop transportation system for transferring the
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12
crop from the sickle knife to the feeder house. This includes two side drapers
19
and 20 each of which includes a canvas extending from an outer guide roller 21
to
an inner guide roller 22 so as to define an upper run of the canvas which
carries the
crop inwardly toward the center of the header.
At the center of the header is provided a feed draper 23 which has a
front roller 24 just behind the cutter bar and a rear roller 25 thus defining
an upper
run of the canvas which carries the crop rearwardly toward the feeder house.
Headers of the general type described above are well known and the
area with which the present invention is concerned is that of the feed section
at the
center of the header which carries the crop from the inner ends of the side
drapers
into the feeder house.
As shown in Figures 3 and 4, a first improvement in the central feeding
area comprises a stripping system for stripping the crop material so that it
is properly
deposited on the upper run of the feed draper 23. The stripping system
comprises a
stripper roller 30 which has a smooth outer surface with an upper tangent 31
lying in
a common plane with the top run of the draper 19, 20. The roller 30 has a
diameter
approximately equal to the diameter of the roller 22 of the draper. The canvas
of the
draper carries a plurality of transverse slats 19A and the roller 30 is spaced
from the
roller 22 by a distance so that the slats just clear the surface of the roller
30 as the
slats pass through the space between the roller 22 and the roller 30.
The roller 30 is carried on end shaft portions 31 which project through
end support plates 32 and 33. At the rear end of the rollers 30 is provided a
housing
34 within which is provided a chain drive 35 for driving the roller 340 at the
same
angular speed as the roller 22. Each of the support plates 32 is carried on a
respective one of a pair of support brackets 36 which are attached to the
front and
rear support rails 37 respectively of the respective draper. Thus the rollers
30 are
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13
supported at the inner ends of the drapers and are located inwardly of the end
roller
of the draper in a common plane with the draper.
Each support plate 32, 33 carries a blade support bar 38 which
extends across between the plates 32 and 33 and underneath the roller 30. The
blade support 34 is positioned so that it can receive a stripper blade 39. The
angle
of the bar 38 is arranged so that the stripper blade 39 when attached thereto
extends from the innermost tangent 40 of the stripper roll downwardly and
inwardly
over the surface of the upper run of the feed draper 23. An upper edge 41 of
the
blade brushes against the peripheral surface of the roller so that material
passing
over the roller 30 is swept off the surface of the roller and runs over the
blade 39.
A side guard blade 42 is mounted at its outer edge on a support frame
member 43 of the header so that the blade 42 extends inwardly over the top of
the
upper run of the draper 23 to a position inward of a lower edge 43 of the
blade 39.
The blade 39 thus extends downwardly onto the upper surface of the blade 42 so
that there is no rubbing of the bottom edge 43 of the stripper blade on the
draper.
The blades 39 and 42 are cut to a length so that they close off any space
between
the stripper roller 30 and the draper 23. As the space between the draper 23
and
the stripper roller can vary along the length of the draper 23. The blades, 39
and 42
are shaped to accommodate this change in space. The draper 23 carries slats
23A
with ends of the slats arranged just inside the inner edge 45 of the blade 42.
Thus the header is improved so that the crop material 46 carried over
the end roller 22 of the draper by the draper passes over the stripper roller
30 and
cannot penetrate between the rollers 22 and 30 due to the close proximity
between
those rollers.
Turning now to Figures 2 and 2A, it will be noted that the front roller 24
of the feed draper 23 is carried on a support immediately rearward of the
cutter bar
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14
15 so that it is fixed to the forward edge of the header. The rear roller 25
is carried
on a bracket 57 mounted on a support pan 50 which extends from the header at a
forward end 50A at the cutter bar 15 at the front of and inwardly of the
support frame
member 43 rearwardly to a rear end 51. At the rear end 51 of the pan is
provided a
pair of side arms 51 B which extend from the rear edge of the pan on
respective
sides of the pan to a rear end 51A carried on the adapter 16 attached to the
feeder
house 17. An open space is thus defined between the arms.
The header including the main beam 11 and the frame element 43 is
carried on the support frame 16 by two bottom links 52 which extend forwardly
from
the frame 16 under the header frame within a respective one of the arms 43 and
support the header frame at a forward end 53 of the links 52. The links are
supported on mounting springs (not shown). A top support link 54 extends
forwardly
from the frame 16 to a bracket 55 at the beam 11. Thus the header can move
upwardly and downwardly in a floating action and can also twist side to side
about a
generally horizontal forwardly extending axis by a differential in the lifting
of the links
52.
Thus the support pan 50 for the feed draper has its forward end
attached to the header and its rearward end attached to the frame 16 so that
it is
necessary for the pan to flex and twist to accommodate the floating and
pivoting
action of the header. The rear roller 25 of the draper 23 is thus mounted on
the pan
50 and therefore also the draper 23 flexes and twists to accommodate such
movement.
At the rear roller 25 on the bracket 57 of the pan 50 is mounted an
optional stripper roller 56 carried on a bracket 56A. The stripper roller, if
provided,
operates similarly to the rollers 30 to strip the crop material from the
draper 23 to
prevent it from being carried under the draper. Immediately behind the
stripper roller
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56 is provided a forward end 58 of a guide sheet 59 which extends from the
stripper
roller 56, or if not provided, from the rear end of the draper 23 rearwardly
to a rear
end 60 at the feeder house. Thus the rear end 60 carried on the frame 16 at
the
feeder house and the front end 58 is carried on the bracket 57 so that the
sheet 59
5 also flexes and twists to accommodate the movement of the header. The sheet
edge 58 may contact the stripper roller in a stripping action.
The sheet 59 has a width substantially equal to the width of the draper
23 so that the material discharged from the draper across the full width of
the draper
is carried rearwardly over the sheet to the feeder house.
10 The movement of the crop material to the feeder house is assisted by
a rotary feed member 70 carried above the sheet 59 with a width substantially
equal
to the width of the sheet 59. The rotary feed member 70 includes a drum 71
which
carries on its outside surface two helical auger sections 72 and 73 arranged
at
respective ends of the drum and arranged so that rotation of the drum in a
counter
15 clockwise direction so as to carry the crop material underneath the rotary
feed
member across the sheet 59 causes the crop material at the side edges of the
sheet
to be drawn inwardly toward a center of the sheet. At the center of the drum
71 is
provided a plurality of fingers or other projecting members as indicated at 75
which
direct the crop material rearwardly to enter the feeder house 17. Thus it will
be
noted that the rotary feed member is wider than the feeder house. The rotary
feed
member has a length so that it fits just inside the stripper rollers 30. The
rotary feed
member has a diameter so that its forward edge substantially directly overlies
the
rear edge of the feed draper and the forward edge of the sheet 59 so that it
can pick
up material from the rear of the draper and carry that material rearwardly.
Thus the
forward edge of the rotary feed member projects to a position forward of a
rear edge
30A of a stripper roller and forward of a rear edge 19A of the draper.
CA 02357825 2001-09-27
16
The rotary feed member is carried on two side arms 76 and 77 which
are mounted at their rear end on a transverse shaft 78 carried on the frame
16. The
shaft 78 is positioned just in front of the front feeder chain pulley 80 so
that the
position of the rotary feed member 70 is maintained substantially constant
relative to
the feeder chain as the rotary feed member pivots upwardly and downwardly on
the
shaft 78 to accommodate changes in thickness of the crop on top of the sheet
59.
The rear of the header is defined by two rear sheets 81 and 82 on
respective sides of the header which define an opening 83 at the rotary feed
member so that the rotary feed member projects through the opening to operate
in
co-operation with the sheet 59 in the area at the rear of the header and on
top of the
sheet 59. Thus the position of the rotary feed member is such that it is
behind the
front of the header and forward of the rear part of the header and sits
intermediate
the rear wall of the header. The header is thus moved as far back close to the
frame
16 as is physically possible and this positioning of the header is not
influenced by
the location of the rotary feed member. In addition the rotary feed member is
of a
size so that it can cooperate with the sheet 59 in properly feeding the crop
material
into the feeder house. It is also located in a position so that it co-operates
with a
feeder chain at all times during its operation and during its movement. Stops
may
be provided to prevent the rotary feed member from engaging the sheet 59 which
could cause damage.
Figure 6 shows a modified arrangement in which the draper 23
extends to the feeder house and the stripper roller 56 and the pan 59 are
omitted.
Thus in this case the feed member 70 co-operates with the upper run of the
draper
in feeding the material into the feeder house.
Turning now to the embodiment shown in Figures 7 through 10, there
is shown a stripper roller arrangement including a stripper roller 301 which
is located
CA 02357825 2001-09-27
17
at the same position as the roller 30 in the embodiment shown in Figure 4 and
operates in basically the same manner but is modified to provide an improved
stripping action.
Thus the roller 301 co-operates with a stripper blade 391 in the manner
previously described to strip the crop material from the stripper roller 301
and to
carry it onto the feed draper as previously described. The roller 301 is
modified so
that it includes two rows 302 and 303 of projections 304. The rows extend
axially
along the roller parallel to the axis 305 of the roller and in the embodiment
shown
there are two such rows arranged diametrically opposed on the surface of the
roller
301. The projections are spaced apart axially so as to leave a portion 306 of
the
peripheral surface 307 of the roller between each projection and the next so
that the
roller is basically cylindrical in shape defining the peripheral surface 307
with the
projections extending outwardly from the peripheral surface to a raised height
above
the surface. The projections have side walls 308 and 309 spaced axially along
the
roller and those sidewalls are, in the example shown, planar and tapered
upwardly
and outwardly from the surface 307. Sidewalls can also be directly parallel so
as to
lie in radial planes of the axis of the roller. Also in another preferred
arrangement,
the side walls may have a first portion at the roller which is parallel and a
second
portion outward therefrom which is tapered since it is preferred to have them
slightly
tapered as shown so that the base of the projection is larger than the top of
the
projection to provide an improved anchoring of the structure of the projection
to the
surface 307.
In the embodiment shown the projections are formed as bent sheet
metal tabs generally of V shape in side elevational view as shown in Figure 7
with
the tabs thus forming a leading surface 310, a trailing surface 311 and an
apex 312.
The base of the legs defining the leading and trailing surfaces is attached at
313 to
CA 02357825 2001-09-27
the surface of the roller.
In an alternative arrangement (not shown) the projections can be
formed as molded elements integrally molded with the wall forming the surface
307
and molded from a suitable plastics or resilient material.
In the embodiment shown there are two such rows of projections but it
will be appreciated that additional rows can also be provided at angularly
spaced
positions around the roller.
The projections of each row are axially aligned with the projections of
the next row so that the number and axial position of the projections is
identical for
the rows allowing those aligned projections to co-operate with correspondingly
shaped recesses 392 in the blade 391. Thus as shown in Figure 8, the blade 391
has a stripping edge 393 which is at or in contact with the surface 307 to
provide a
stripping action. That stripping edge 393 has a plurality of recesses 392 each
shaped so that the aligned projections 304 can just pass through that recess
as the
roller rotates in the stripping direction R. Thus the recesses have side walls
394 and
395 which match the side walls 308 and 309 of the projections, as defined
above,
and are therefore in the embodiment shown tapered inwardly toward one another
from the stripping edge toward the bottom of the blade. The recesses further
have a
base 396 which matches the width of the apex 312 of the projections.
As shown in the side elevation of Figure 7, the roller is mounted on the
end bracket 33 so that the roller is located at a spacing from the end guide
roller 22
at the draper sufficient that the apex 312 just clears the top of the slats
19A of the
draper. In most embodiments it is not practical to provide accurate timing
between
the slats and the draper and the projections on the roller so that it is
simply assumed
it is possible that the slats and the projections may pass one another apex to
apex
and therefore the spacing is set up to provide clearance at that position to
allow
CA 02357825 2001-09-27
19
them to pass, should that occur.
As shown in Figure 9, the projections are shaped so that the angle
between the leading surface 310 and the trailing surface 311 indicated at
angle A is
at the order of 90° and is preferably greater than 60°. This
provides a projection
which is relatively wide and shallow with the leading edge arranged at an
angle to
the axial plane at the order of 45°. It will be appreciated that this
relatively shallow
angle relative to the radial plane reduces the aggression of action of the
leading
surface but it has been found that an angle of the order of 60° or
greater provides a
sufficiently aggressive action on the crop material so that the projections
and
particularly the leading surface of the projections as they pass upwardly
between the
draper and the roller 301 act to lift the crop off the slats and over the gap
between
the draper and the roller thus acting to carry the crop and strip the crop
from the
draper so that it is transported over the roller for discharge.
While a bare cylindrical roller without such projections can act to carry
the crop in certain conditions, some crop conditions and crop materials in the
absence of the projections can be forced by the slats to enter the space
between the
draper and the stripper roller so as to force crop material into that space
and cause
blockages. The provision of the projections ensures that this does not occur
and
causes all crop material to be lifted from the draper, separated from the
slats and
carried over the stripper roller.
The stripper blade 391 extends from the stripper edge 393 at the
surface 307 of the roller downwardly and inwardly as shown in Figures 7, 9 and
10
for discharge at the bottom end of the blade. In order to allow the
projections to
pass through the blade while allowing the strip edge 393 to rest at the
surface 307,
the recesses are provided and it is important to ensure that the projections
are
shaped and arranged relative to the blade so that the projections themselves
do not
CA 02357825 2001-09-27
cause crop material to be forced through those recesses which again would
cause
blockages.
For this reason the relatively shallow angle of the leading surface 310
is selected so that the angle of attack of the leading surface is the least
aggressive
5 which can be accepted while still acting to strip material at the draper.
This shallow
angle as shown in comparing Figures 9, 7 and 10 in that order shows the
passage of
the leading surface 310 and the apex 312 through the recess in the blade 391.
It will
be noted in Figure 9 that the leading surface as it is initially commences to
pass
through the recess at the base of the projection is arranged at an angle B
relative to
10 the outwardly facing surface of the blade 391 which angle B is greater than
90°. As
the leading surface 310 continues to pass through the recess as shown in
Figure 7,
the leading surface 310 remains at an angle greater than 90° for the
majority of the
distance of movement of the leading surface into the recess. Thus in Figure 7
where
most of the leading surface has already passed through the recess, the angle
of the
15 leading surface relative to the blade approaches 90°. It will be
appreciated that,
when the leading surface 310 is at right angles to the blade 391 there is
substantially
no force on the crop tending to push the crop into the recess 392. Only when
the
leading surface is at an angle so that the angle B is less than 90° to
the surface 392
is there a force tending to push the crop material into the recess which could
cause
20 pinching of the crop between the projection and the recess. The angle of
the blade
and the angle of the leading edge is therefore arranged so that the angle B
passes
to a position less than 90° only at or when the projection is
substantially wholly
through the recess as shown in Figure 10. It will be appreciated that this
condition
can be obtained by providing a shallow angle of the leading surface 310 as
shown or
by reducing the angle to the vertical of the blade 391. The angles as shown
where
the projection is triangular with approximately 90° between the leading
and trailing
CA 02357825 2001-09-27
21
surfaces and where the angle of the blade to the vertical of the order of
35° provides
an operating arrangement which avoids the crop from being pushed through the
recesses and pinched between the projection and the recess. However it will be
appreciated that minor changes to these angles can be used if necessary to
increase the aggressive angle of the leading surface and by reducing the
inward
incline of the blade. However it is undesirable to decrease the angle A to an
angle
less than 60°.
Turning now to Figures 11 and 12 there is shown a further modified
arrangement in which the roller 301 is omitted and the blade 391 is arranged
to co-
operate directly with the cylindrical portion of the draper 491 and the slats
492. Thus
the draper 491 is wrapped around the cylindrical surface of the end guide
roller 493
to provide a cylindrical surface 494 against which the edge 393 of the blade
391 is
located to provide a stripping action.
In this embodiment the slats 492 are modified so that each slat is
defined by a row of projections 494. The projections 494 are again arranged in
axially spaced rows so that projections of each slat 492 are aligned with the
projections of the next 492 and aligned with the recesses 392. The projections
494
are shaped as previously described in the embodiment of Figure 7 so that the
leading surface, the apex and the trailing surface provide a triangular shape
which
co-operates with the blade and the opening 392 as previously described to
allow the
leading surface to pass through the blade without forcing crop material into
the
opening 392. Thus the stripping blade 391 co-operates directly with the end
roll of
the draper in an effective stripping action while the slats are shaped and
arranged so
that they provide the necessary transport action conventional and in draper
canvas
while the slats avoid interfering with the stripping action of the blade by
the co-
operation of the projecting portions define the slats with the recesses 392 of
the
CA 02357825 2001-09-27
22
blade.
In order to ensure that the aligned projections remain in proper
alignment with the recesses in the blades, it is desirable to accurately
maintain the
draper canvas in a tracking path and one suitable arrangement for guiding the
draper in this movement is described in US application 09/590,128 filed June
9,
2000 by Shearer and assigned to the present applicant. This application
corresponds to Canadian application 2,311,019 filed June 8th 2000.
In view of the reduced degree of stiffness provided by the slats since
those slats are now formed by individual axially spaced projection, it is
desirable to
provide additional support for the draper canvas at spaced positions along the
length
of the draper canvas. It is also necessary to provide a connecting element for
the
ends of the draper canvas which does not project upwardly from the draper
canvas
to interfere with the blade 391. Continuous draper canvasses are commercially
available or alternative coupling elements can be provided which connect the
ends
of the draper canvas without providing an outwardly projecting bar. Thus the
only
outward projection from the draper canvas as it moves past the blade is
provided by
the projections forming the slats so that the stripping blade can provide an
effective
stripping action with the stripping edge at or in contact with the surface
494.
Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same made
within the spirit and scope of the claims without departing from such spirit
and
scope, it is intended that all matter contained in the accompanying
specification shall
be interpreted as illustrative only and not in a limiting sense.
