Combine harvester residue spreader fin shaped to increase spreading action

Abstract

A residue management system of a combine harvester includes a tailboard with a guide surface and guide fins for spreading of the residue to the sides. At least one of the fins includes a leading portion which is smoothly concavely curved up to a trailing portion which intersects with the leading portion at a change in direction or defined bend in the sheet metal. The trailing portion thus extends across and intersects with a path of the residue as it passes along the concave side surface at the leading portion and leaves the end of the leading portion to apply increased pressure on the stream and thus increase the spreading action. The trailing edge of the trailing portion is also inclined to a line across the trailing portion at right angles to the tailboard surface which causes the residue to leave the trailing edge at different angles.

Claims

1. A discharge apparatus for spreading residue from a combine harvester comprising: a tailboard having a tailboard surface across which the residue is directed; at least one guide fin extending outwardly from the tailboard surface so that a stream of the residue engages one side surface of the at least one guide fin as it passes over the tailboard surface; the at least one guide fin having a leading surface portion along which the residue passes in a downstream direction, a trailing surface portion along which the residue passes after the residue leaves the leading surface portion and a trailing edge of the trailing surface portion spaced downstream of the leading surface portion from which the residue leaves the at least one the guide for spreading; the leading surface portion having a concave side surface leading in the downstream direction to a trailing end of the leading surface portion; the trailing surface portion having a leading end intersecting with the trailing end of the leading surface portion at a line transverse to both the leading surface portion and the trailing surface portion such that the residue leaving the trailing end of the leading surface portion engages onto the trailing surface portion at the line; the trailing surface portion having a side surface onto which the residue passes from the concave side surface of the leading surface portion which is arranged at an angle greater than 0 degrees to the concave side surface at the trailing end of the leading surface portion so as to define a change of direction at the line; the trailing surface portion thus extending across and intersecting with a path of the residue as it passes along the concave side surface at the trailing end of the leading surface portion such that the residue impacts on the trailing surface portion at the line; wherein the angle between the concave side surface of the leading surface portion and the side surface of the trailing surface portion is arranged to cause the stream at the change in direction to spread on the at least one guide fin in a direction outwardly from the tailboard surface; and wherein the trailing edge of the trailing surface portion is arranged at an angle to a line at a right angle to the tailboard surface so that an end of the trailing edge at the tailboard surface is downstream of an end of the trailing edge remote from the tailboard surface so as to cause multiple release points longitudinally of the guide fin depending on a distance outwardly from the tailboard surface that the material leaves the trailing edge.

2. The discharge apparatus according to claim 1 wherein the trailing surface portion is planar.

3. The discharge apparatus according to claim 1 wherein the at least one guide fin is formed of sheet metal and the change in direction between the leading surface portion and the trailing surface portion is defined by a defined bend in the sheet metal.

4. The discharge apparatus according to claim 1 wherein the line extends substantially at a right angle to the tailboard surface.

5. The discharge apparatus according to claim 1 wherein the angle at the change in direction is greater than 0 degrees up to 45 degrees.

6. The discharge apparatus according to claim 1 wherein the angle at the change in direction lies between 5 degrees up to 30 degrees.

7. The discharge apparatus according to claim 1 wherein the trailing edge of the trailing surface portion is inclined so that the end of the trailing edge remote from the tailboard surface is closely adjacent the line so that the trailing surface portion is substantially triangular.

8. A method for spreading residue from a combine harvester comprising: directing a stream of the residue across a tailboard surface of a tailboard; engaging the stream of the residue against one side surface of at least one guide fin as it passes over the tailboard surface where the at least one guide fin extends outwardly from the tailboard surface; the at least one guide fin having a leading surface portion along which the residue passes in a downstream direction, a trailing surface portion along which the residue passes after the residue leaves the leading surface portion and a trailing edge of the trailing surface portion spaced downstream of the leading surface portion from which the residue leaves the at least one guide fin for spreading; the leading surface portion having a concave side surface leading in the downstream direction to a trailing end of the leading surface portion; the trailing surface portion having a leading end intersecting with the trailing end of the leading surface portion at a line transverse to both the leading surface portion and the trailing surface portion; causing the stream of residue leaving the trailing end of the leading surface portion to engage onto the trailing surface portion at the line; arranging a side surface of the trailing surface portion onto which the stream of residue passes from the concave side surface of the leading surface portion at an angle greater than 0 degrees to the concave side surface at the trailing end of the leading surface portion so as to define a change of direction at the line; causing the residue to impact on the trailing surface portion at the change in direction; causing the stream at the change in direction to spread on the at least one guide fin in a direction outwardly from the tailboard surface; arranging the trailing edge of the trailing surface portion at an angle to a line at a right angle to the tailboard surface so that an end of the trailing edge at the tailboard surface is downstream of an end of the trailing edge remote from the tailboard surface; and causing multiple release points longitudinally of the guide fin depending on a distance outwardly from the tailboard surface that the material leaves the trailing edge.

9. The method according to claim 8 wherein the trailing surface portion is planar.

10. The method according to claim 8 wherein the at least one guide fin is formed of sheet metal and the change in direction between the leading surface portion and the trailing surface portion is defined by a defined bend in the sheet metal.

11. The method according to claim 8 wherein the line extends substantially at a right angle to the tailboard surface.

12. The method according to claim 8 wherein the angle at the change in direction is greater than 0 degrees up to 45 degrees.

13. The method according to claim 8 wherein the angle at the change in direction lies between 5 degrees up to 30 degrees.

14. The method according to claim 8 wherein the trailing edge of the trailing surface portion is inclined so that the end of the trailing edge remote from the tailboard surface is closely adjacent the line so that the trailing surface portion is substantially triangular.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) One embodiment of the invention will now be described in conjunction with the accompanying drawings in which:

(2) FIG. 1 is an isometric view of a rear section of a straw chopping and spreading arrangement for mounting on a combine harvester in accordance with the present invention.

(3) FIG. 2 is an isometric view of the components of FIG. 1 from the same side and below.

(4) FIG. 3 is an isometric view of the tailboard of FIG. 1 from the rear corner showing the construction of the outermost guide fin.

(5) FIG. 4 is an isometric view from the bottom of one of the fins of the tailboard of FIG. 1.

(6) FIG. 5 is an isometric view from one side and below showing the stream of residue material as it impacts on the rear inclined portion of the guide fin.

(7) FIG. 6 is a top plan view of one guide fins showing the inclined rear portion in plan.

(8) FIG. 7 is a side elevational view of the guide fin of FIG. 6 showing the stream of residue passing over the front curved portion of the tin and onto the inclined rear portion.

(9) In the drawings like characters of reference indicate corresponding parts in the different figures.

DETAILED DESCRIPTION

(10) A combine harvester is shown in the above-mentioned US patents of the present applicant. This comprises a combine harvester housing mounted on ground wheels for transport over a ground in conventional manner. The combine harvester is not shown since many different designs are available and well known to one skilled in the art. The combine harvester includes a straw separation section and a sieve section. Again these elements are conventional and provide arrangements for separation of the straw from the crop material allowing the seed material to fall through to the sieve at which seeds are separated from the seed material leaving the chaff or other lighter materials on top of the sieve to be carried away from the sieve by an air flow through the sieve as is well known.

(11) The rear of the combine is provided is a rear hood into which air from the straw separation system and the sieves enters and into which straw is discharged rearwardly for and is guided by guide wall and by an operable guide panel in the hood section into a chopper and spreader generally indicated at 11.

(12) This arrangement is well known and commercial products are readily available from Redekop Manufacturing and other manufacturers of straw choppers of this type.

(13) The chopper has a horizontal upper mounting flange 1 which attaches to a corresponding bottom flange of the hood of the combine. This forms a rectangular open mouth at the top of the chopper which corresponds in shape to the rectangular lower opening of the hood so that all material discharging from the guide walls falls into the upper part of the housing and enters the inlet 2 of the chopper. The housing can also receive material from the sieves including the chaff and any non-grain material using known transfer devices (not shown).

(14) The chopper comprises a housing 3 attached to the top mounting flange and depending therefrom and defined by side walls 4 at opposite sides of the hood and generally co-planar therewith. Bridging the side walls 4 is provided a bottom wall 5 and a top wall 6 which extend across the width of the chopper and form a generally cylindrical containing surface for receiving the chopper rotor. The rotor includes a hub with a plurality of radially extending flails or blades carried on the rotor for rotation therewith around the axis of the rotor which is arranged across the width of the chopper.

(15) The top wall and the bottom wall define at the upper part of the housing the inlet 2 into which the straw can be guided from the hood. The chaff may be carried from the end of the sieve over the space between the end of the sieve and the front edge of the bottom wall 6 so as to carry the chaff in the air stream from the sieve over the plate and into the opening 2.

(16) The top wall includes a generally vertical portion 10 which extends downwardly from the top flange 1 to the top of the rotor. The top wall 5 further includes a curved section 10A which extends around the top of the rotor to a rear edge 10B which defines the top edge of the rear discharge opening 10C through which the material exits in the stream of air and chopped materials generated by the rotation of the rotor within the housing.

(17) The chopper can be configured with a left 12 and a right 13 tailboard as known in U.S. Pat. No. 6,939,221. Each tailboard incorporates six fins 14 that pivot about front mounting holes and can slide along a back slot to a required location where it is fixed by a locating screw. This tailboard has two locations for a leading edge thus defining a first leading edge fin placement and a second placement for cooperation with the common rear slots. The first fin placement is used for a high air velocity rotor and optimizes the product spread on a wide spread pattern. The second placement pattern is utilized with a traditional rotor most often used with narrow spread aggressive cutting chopper having low air velocities.

(18) As shown in more detail in the above patent, the left and right tailboards are mounted to the straw chopper 11 with side mount plates 19. The tailboard's angular positioned is fixed with a spring-loaded pin in a slot on each side of the combine. A gas spring 21 on each side of the housing counter balances the weight of the tailboard allowing the operator to easily adjust each of the tailboard positions.

(19) The tailboards pivot on a common axis. The axis is defined by the pivot 24 in each side plate and the center pivot. Once each assembly is attached to the chopper each tailboard is fully adjustable independent of each other.

(20) The present invention is primarily concerned with the construction and arrangement of the fins of the tailboard 13, 14. It will be appreciated that a common tailboard can also be used in this current arrangement.

(21) As is well known conventional fins or guide members are arranged with a leading edge adjacent the front of the tailboard so that the crop engaging onto the main surface of the tailboard also engages the side surfaces or guide surfaces of the fins adjacent the leading edge. The fins each extend rearwardly from the leading edge to a trailing edge adjacent the rear edge of the tailboard. Each of the fins has a shape which is preferably generally curved so as to define a contact side which is the concave side of the fin with the curvature carrying the fin toward the side edge of the tailboard. Thus the crop material is carried by the fins as the crop material moves rearwardly of the tailboard on the inside surface of the concave fin so that the material is moved outwardly to be discharged in a spread pattern rearwardly and to the sides of the tailboard. The tailboard thus defines a series of guide surface portions between the fins with each fin acting as a guide member relative to the respective guide surface portion.

(22) In the present arrangement, the fins are modified so as to provide an additional functionality with the outermost pair of fins modified with a more complex structure and arrangement. Thus, referring to FIGS. 3 and 4, the inner fins include an additional feature while the outermost pair of fins indicated at 30 define a first fin which is indicated at 32 and extends from a leading edge at or adjacent the front edge of the tailboard 13 to a trailing edge 32A rearward of the leading edge but forward of the rear edge of the tailboard. The fin includes an inclined lower surface 32B so that the fin commences at zero height and gradually increases in height to the trailing edge 32A. In this way any crop material engaging the lower edge 32B can slide off that edge as the crop material moves rearwardly in the airstream.

(23) The next adjacent fin is modified to include a second part generally indicated at 31. This fin part 31 is made up of two sheets 33 and 35 where the first sheet 35 forms the main body of the fin and the sheet 33 forms a second part attached to the main body of the fin and defining a generally channel shaped portion.

(24) The sheet 35 as shown in FIG. 4 has a top flange 35A at the top edge for bolting to the underside of the tailboard at the guide surface portion of the tailboard using the mountings previously described. The sheet 35 when mounted by the flange 35A extends at right angles to the surface of the tailboard. The sheet or main body 35 of the fin extends from a leading edge 40 rearwardly of the tailboard to a trailing edge 35A located at the rear of the tailboard adjacent one side. The sheet 35 has a bottom edge 35B which is parallel to the flange 35A and the top edge of the sheet 35. The leading edge 40 commences at a front end 40A and extends rearwardly while increasing in height to a trailing end 40B of the leading edge 40. Again the inclined leading edge 40 commencing at zero height allows the crop material to slide over this leading edge to be released from the fin should any crop material be trapped around that leading edge. Thus some of the crop slides along the sheet 35 along the concave side so as to be guided thereby in the spreading action.

(25) At the bottom edge 35B of the sheet 35 is attached the second sheet 33. The sheet 33 has a mounting flange 33A at its side edge. The mounting flange 33A is arranged to lie along the outside surface of the sheet 35 at the lower edge 35B so as to be bolted thereto by attachment bolts 100. The flange 33A is arranged at an angle to the main body of the sheet 33 so that the sheet 33 is inclined from the lower edge 35B in a direction downwardly from the lower edge and to the side of the sheet 35 which is the concave side.

(26) The angle of the sheet 33 to the sheet 35 is of the order of 120 degrees but the angle can vary between 90 degrees and approximately 150 degrees.

(27) As shown in FIG. 4, each of the sheets 33 and 35 is curved in bottom plan view so that the adjoining edges at the side edges of the sheet 33 are also curved. The width of the sheet 33 is substantially constant along its length so that the edges are equidistantly spaced along its length from the sheet 35. In cross section the sheets are flat so as to define a channel member with the sheet 33 at the base and the sheet 35 upstanding from that base and with the angle between the sheets of the order of 120 degrees as previously stated. The sheet 35 is directly attached to the underside of the tail board so as to extend at right angles to that surface. Thus the sheet 34 is inclined toward the surface of the tail board. However the lower edge 33B of the sheet 33 is spaced downwardly from the surface of the tailboard so as to allow any crop material to enter the space therebetween to be channeled by the curved fin defined by these two sheets including the main body 35 and the additional sheets 33.

(28) As previously stated the sheet 35 has a leading edge 40 extending from the end 40A to the end 40B. The sheet 33 has a leading edge 33C extending from an end 33D to a lower end 33E. Again the edge 33C is inclined rearwardly. The sheet 33 thus has an outer edge 33F which is considerably shorter than the inner edge 33G which is in turn considerably shorter than the edge 35E of the sheet 35. Sheet 33 acts to confine air and flowing materials into the channel which is defined on the concave side of the sheet 35.

(29) Referring again to FIG. 4, the leading edge 40 of the sheet 35 terminates at the point 40B where it joins the outer edge of the sheet 35. The leading edge 33C has its inner end 33D spaced rearwardly from the end 40B of the leading edge 40. This forms a recessed portion 41 ensuring that any crop material flowing over the leading 40 is released from the leading edge 40 before it engages the leading edge 33C. This ensures that there is no shoulder or notch against which the crop material can engage to inhibit the free flow of the material over this edge. It will be appreciated that some crop material may fold over the leading edge in its movement rearwardly from the discharge opening onto the tailboard surface. It is necessary or highly desirable to ensure that the crop material is prevented from hanging up and hence the recess 41 at the junction between the outer edges of the sheet 35 and the sheet 33.

(30) The two fins 31 and 32 are separate from one another and adjustably mounted on the tailboard. Each fin is mounted and pivots about a front mounting hole. Thus both fins 31 and 32 can be adjusted as previously described so that its forward end forms a pivot and its rearward end can be moved side to side in slots 16 (FIG. 2). A link connects the fin 32 to the next fin 31 so that these fins are adjustable in common movement. The link 36 however only connects the outermost fin 32 to the next adjacent fin 31 and there is no further linkage to any of the remaining fins. The link is merely a simple connection with no ability to effect adjustment of any of the fins except to control the common movement between the two fins 32 and 31.

(31) Thus the outer two most fins 30 on each side of the tailboard assemblies are configured to focus the high velocity air stream generated by the fan end rotor 26 on the chopped residue. The acceleration of the residue provides a wide spread under adverse side wind conditions. The outer two fins consist of the large fin 31 that carries and directs most of the residue and the smaller fin 32 that alters the direction of the high velocity air to provide a tangential thrust on the larger fin and greater residue acceleration.

(32) The outermost small fin 32 on the tailboard is used to redirect the highest velocity air into a tangential vector with the rear end of next adjacent or second large fin 31. This provides the greatest acceleration of material and the most efficient use of the force available with the high velocity air. If the small fin 32 was removed the high velocity air would crash into fin 31 and bounce off of the fin taking material with it, most likely landing beside the chopper. The intention is to slowly turn the high velocity air and apply its energy to the residue. Surfaces 33 and 35 are attached to fin 31 so that the air, that is reflected off of the residue when being accelerated, is held captive and can not bounce off in another direction. More of the energy in the air is used to accelerate the residue than without these surfaces present. Adding surface 33 has a huge impact on the retained air velocities. In the field, removal of the surface 33 reduces the spread width by 25%.

(33) The residue primarily travels on the vertical fin surface 35, however conditions exist with tough, green straw where the residue discharged from the chopper does not flow easily and will contact the other surfaces. Surface 33 serve to contain and focus the air on the residue stream. Outer surface 33 is primarily used to contain the air that is being reflected from surfaces 35. The small fin 32 is positioned to direct the high velocity air tangentially on to the rear end of fin surface 35 of large fin 31. The relative position of the two fins 31 and 32 is maintained in an optimum tangential relationship with link 36. Adjustment of the two fins is available without the need to tune the relative fin positioning.

(34) The large fin 31 is constructed so that plugging is minimized. In tough field conditions heavy, wet residue is discharged down the leading edge 40 of fin surface 35. The adjoining surface must start approximately 0.5 inch behind the previous surface, as indicated at 41. This enables any residue traveling down the leading edge to clear the next surface, and therefore avoids plugging situations. The fin 32 has a passive leading edge since high velocity air must be able to pass by all surfaces, keeping the tough sticky residue moving.

(35) Turning now to FIGS. 5, 6 and 7 the arrangement is further detailed in which at least two of the guide fins 31 attached by a flange 311 to the guide surface of the tailboard includes a first leading surface portion 312 along which the residue passes extending from a leading edge 313 to a rear end 314 of the leading portion. The fin 31 further includes a trailing portion 315 along which the residue passes after the residue leaves the leading portion 312 at its rear end 314. The fin extends to a trailing edge 316 of the trailing portion 315 spaced downstream of the leading portion 312 from which the residue leaves the guide fin for spreading.

(36) The leading portion 312 is curved smoothly and constantly from its leading edge 313 up to the end 314 of the leading portion at the trailing portion 315 so that the side surface of the leading portion 312 over which the residue slides is concave.

(37) The trailing portion 315 intersects with the leading portion 312 at the end 314 which defines a change in direction where the side surface at the trailing portion is arranged at an angle A to the leading portion 312.

(38) The intersection at the end 314 of the forms a sharp change in direction. For example where the fin is formed of sheet metal, the change in direction between the leading and trailing portions is defined by a defined bend in the sheet metal. Thus the defined bend at the intersection 314 lies along a line substantially at right angles to the path of residue along the leading portion which thus lies along a line substantially across the leading portion at right angles to the tailboard surface. The trailing portion 315 thus extends across and intersects with a path of the residue as it passes along the concave side surface at the leading portion and leaves the end 314 of the leading portion 312.

(39) The trailing portion 315 is planar or flat as best visible in FIG. 6. In this way as best shown in FIG. 7, the residue stream at the intersection 314 impacts on the surface of the portion 315 and is caused to spread downwardly by that impact to form a wider fan of streams as indicated at 317, 318, 319 and 320. This is intended merely to be illustrative and the streams form a constant fan or material diverted downwardly from the surface of the tailboard 15.

(40) As best shown in FIG. 7, the trailing edge 316 of the trailing portion 315 forms a straight line which is inclined to a line 321 across the trailing portion at right angles to the tailboard surface. In this way, an end 322 of the trailing edge remote from the tailboard surface is upstream of, or closer to the leading edge 313, than an end 323 of the trailing edge at the plane of the tailboard surface. In this way the trailing portion 315 is substantially triangular as defined by its top edge at the tailboard, by its leading edge at the intersection 314 and by its trailing edge 316.