Weed seed destruction on a combine harvester
A combine harvester separates crop into straw and chaff and weed seeds using a sieve, a chopping rotor with a spreading device and at least one weed seed devitalization section. The components can be operated in a first mode where both the first material and said second material are directed to the chopper and a second mode the first material is directed to the chopper inlet and the second material is directed to the WSD. This can be effected by providing a guide wall which has a leading edge attached adjacent a rear edge of the sieve and extends rearwardly therefrom. The chopper and the WSD can also be moved to provide the change of modes. A construction of destructor mill with an outer stator on the housing is also disclosed along with a method of feeding the lost grain to the WSD.
1 . A combine harvester comprising;
a separation system for separating harvested crop into grain, a first material comprising straw at a first location and a second material comprising chaff and weed seeds at a second location; and
a weed seed destructor section comprising:
a rotor rotatable about a rotor axis;
a stationary stator around which the rotor rotates to cause impacts of the weed seeds back and forth between the rotor and the stator;
the rotor comprising an inner rotor portion and at least one annular rotor ring portion which carries a plurality of rotor surfaces and rotates around the rotor axis outwardly of the inner rotor portion;
the stator comprising an inner annular stator ring portion which carries a plurality of angularly spaced, axially extending stator bars and is located outwardly of the inner rotor portion and inwardly of the annular rotor ring portion, each stator bar being spaced from a next stator bar by an axially extending space therebetween along a length of the stator bars with second material passing through the axially extending space;
an inlet for the second material to engage the rotor and the stator;
a discharge opening at which the second material is discharged after said impacts;
and an outer stator structure surrounding the rotor ring of the rotor;
the outer stator structure including an outer guide wall guiding the second material exiting outwardly from the rotor angularly around the rotor axis to the discharge opening;
said at least one annular rotor ring portion having openings therein through which the second material passes;
the outer guide wall being located directly adjacent said at least one annular rotor ring portion with the second material passing though the openings impacting the outer guide wall;
the outer guide wall being shaped with impact surfaces different from a cylindrical surface surrounding said at least one annular rotor ring portion.
2 . The combine harvester according to claim 1 wherein said at least one annular rotor ring comprises a single outer rotor ring which defines an outermost ring of the rotor.
3 . The combine harvester according to claim 2 wherein the outer wall includes a plurality of angularly extending wall surface portions at spaced positions around the axis each connected to the next so as to form the outer guide wall into a continuous guide surface around the axis, which wall surface portions are at an angle to one another so as to define a change in direction in the continuous guide surface over which the second material passes to form said impact surfaces on said outer guide wall.
4 . The combine harvester according to claim 3 wherein the angularly extending wall surface portions form a straight section of the continuous guide surface upstream of the change in direction therebetween.
5 . The combine harvester according to claim 3 wherein the wall surface portions define a first planar surface meeting a second planar surface at a first apex at the change in direction where the second planar surface meets a third planar surface at a second apex at the change in direction.
6 . The combine harvester according to claim 3 wherein the outer wall defined by said wall surface portions is polygonal in cross section.
7 . The combine harvester according to claim 1 wherein the discharge opening is located in the outer guide wall for discharge of the second material after said impacts and wherein the inlet comprises an inlet duct having duct walls directing the second material along a direction path defined by the duct walls which is inclined to the rotor axis and directed toward the outer guide wall at a position angularly spaced from the discharge opening.
8 . The combine harvester according to claim 7 wherein direction path defined by the duct walls impinges on the outer wall at a location immediately downstream of the discharge opening.
9 . The combine harvester according to claim 1 wherein the outer wall includes a smooth discharge section angularly downstream of said impact surfaces extending to said discharge opening.
10 . The weed seed destructor section according to claim 1 wherein the inlet is located in a wall generally radial to the rotor axis.
11 . The weed seed destructor section according to claim 10 wherein the inlet is located in the wall at a position spaced from the rotor axis.
12 . A combine harvester comprising;
a separation system for separating harvested crop into grain, a first material comprising straw at a first location and a second material comprising chaff and weed seeds at a second location; and
a weed seed destructor section comprising:
a rotor rotatable about a rotor axis;
a stationary stator around which the rotor rotates to cause impacts of the weed seeds back and forth between the rotor and the stator;
the rotor comprising an inner rotor portion and at least one annular rotor ring portion which carries a plurality of rotor surfaces and rotates around the rotor axis outwardly of the inner rotor portion;
the stator comprising an annular stator ring portion which carries a plurality of angularly spaced stator bars and is located outwardly of the inner rotor portion and inwardly of said at least one annular rotor ring portion, each stator bar being spaced from a next with the second material passing therebetween;
an inlet duct carrying the second material to engage the rotor and the stator;
a discharge opening at which the second material is discharged after said impacts;
a stationary outer wall surrounding the rotor and guiding the second material exiting outwardly from the rotor angularly around the rotor axis to the discharge opening;
the inlet duct having duct walls directing the second material along a direction path defined by the duct walls which is inclined to the rotor axis and directed toward the outer wall at a position angularly spaced from the discharge opening.
13 . The combine harvester according to claim 12 wherein the direction path defined by the duct walls impinges on the outer wall at a location immediately downstream of the discharge opening.
14 . The weed seed destructor section according to claim 12 wherein the inlet duct is located in a wall generally radial to the rotor axis.
15 . The weed seed destructor section according to claim 14 wherein the inlet duct is located in the wall at a position spaced from the rotor axis.