Releasable fastening arrangement for straw chopper blade

ABSTRACT

A fastening arrangement for fastening a blade to a rotor of a straw chopper. The fastening arrangement comprising a bolt that is inserted into a blade hole in the blade and into a plate hole in a mounting plate extending from the rotor and into a retaining element that retains the bolt in the holes. The retaining element can be separated from the bolt. The bolt and the retaining element are fixed against rotation by the mounting plate.

INFORMATION

DETAILED DESCRIPTION OF THE INVENTION

DETAILED DESCRIPTION

A harvesting machine shown in FIG. 1 in the form of a combine is supported on front driven and rear steer able wheels and and is provided with an operator's cab from which it can be controlled by an operator. A grain tank is located behind the operator's cab . Grain temporarily stored in the grain tank is discharged into a grain cart or truck by an unloading auger . The grain tank is supported on a frame formed by two side sheets. Crop harvested by a harvesting assembly, not shown, is directed into the combine by feeder house . The harvested crop is directed to a threshing assembly. In the illustrated embodiment the threshing assembly comprises a transverse threshing cylinder and associated concave . A transverse beater directs the large components of the threshed crop to straw walkers . The grain and chaff released from the harvested crop is directed to the grain pan by the concave and the straw walkers . The grain pan directs the grain and chaff to the cleaning assembly. The cleaning assembly comprises a series of sieves which receive the grain and chaff a cleaning fan directs an air blast upwardly through the sieves to separate the chaff from the grain. The chaff being blown out the rear of the combine. The clean grain is collected on the floor of the combine and directed upwardly by an elevator, not shown, to the grain tank . The large components of the harvested crop are conducted over the straw walkers over a straw guide vane to a straw chopper .

The straw chopper includes a hollow cylindrical rotor with blades distributed around its circumference and over its length that are pendulously suspended on the rotor . The rotor is rotated in a housing about an approximately transverse horizontal axis. The rotating blades coupled to the rotor in combination with the shear bars reduces the size of the threshed-out large crop components. A distributing arrangement is arranged downstream from the straw chopper . the distributing arrangement comprises a number of guide arrangements arranged alongside each other in the form of straw guide vanes that are mounted underneath a straw distributor hood .

The present invention is directed to a fastening arrangement for the blades to the rotor . FIG. 2 shows an exploded view of a first embodiment of such a fastening arrangement. The blades that are equipped on their longitudinal sides and preferably on their outer ends with ground edges are fastened in pairs to a mounting plate that is welded to the rotor or fastened by other means. One blade is located on each side of the mounting plate . More than two blades could also be fastened to the mounting plate . The mounting plate extends in the direction of rotation of the rotor . The mounting plate is provided with a hole extending in the axial direction of the rotor .

The blades are fastened to the mounting plate by a bolt , two sleeves and , a spacer as well as a retaining element . A Belleville spring can be applied to the bolt and is in contact with its head . In the assembled condition the shank of the bolt extends through a central hole in the spring , a central opening in the first bushing , a blade hole in the first blade , an opening in the first spacer that is formed in the shape of a washer, a plate hole in the mounting plate , a central opening in the second sleeve , a blade hole in the second blade and through the retaining element .

Each of the blade holes in the blades engage circular cylindrical sections of the sleeves and . On the sections the blades are pendulously supported, so they are free to rotate about the longitudinal axis of the bolt .

At the end remote from the head of the bolt the retaining element is provided with a ring-shaped head projecting radially that projects from an axial shank of the retaining element . The length of the shank of the retaining element is dimensioned in such a way that in the assembled condition of the fastening arrangement, the shank extends through the second sleeve , the plate hole in the mounting plate , through the spacer and the first sleeve . Here the blade holes of the blades are arranged on the circular cylindrical sections of the sleeves and . The cross sections of the shank , the sleeves and , the plate hole and the spacer are not circular, but are selected as elliptical in shape and conform at least approximately with each other. Thereby the result is that the retaining element is coupled, fixed against rotation, to the mounting plate , as soon as the shank is inserted into the plate hole . It cannot rotate about its longitudinal axis. The sleeves and and the spacer are also fixed to the mounting plate about its axis by means of the retaining element as soon as they are applied to the shank of the retaining element and the latter is located on the mounting plate .

The bolt is removable fastened to the retaining element by a pin-shaped locking element , which is rigidly connected to the bolt , and extends radially from the bolt in the vicinity of the end remote from the head . The bolt can be inserted into the retaining element through an axial opening of the retaining element that conforms to the cross section of the bolt and the locking element . The opening has the shape of a keyhole for a key with keybits located diametrically opposite each other.

On the basis of FIG. 3 it can be seen that a helically-shaped surface is provided at the end face of the head of the retaining element that partially surrounds the opening . The helically-shaped surface approaches (in the azimuthal direction) successively the end face of the head , with increasing distance from the contour of the opening , through which the locking element is inserted. The surface comprises an azimuthal angle region of approximately 120°. At its end spaced away from the aforementioned contour of the opening a recess in the form of an axial depression is provided in the helically-shaped surface . The locking element comes into contact with the helically-shaped surface , when the bolt is inserted into the retaining element .

In order to perform the locking, the bolt is inserted into the opening of the retaining element and rotated by means of an appropriate tool applied to its head (wrench), so that the locking element rotates in counterclockwise direction as seen in FIG. 2 when the fastening arrangement is viewed from the left. Due to the helical shape of the surface the bolt is drawn more and more into the retaining element when it is rotated against the force of the spring . If the locking element , after crossing over the angular region of the surface , reaches the recess , then the spring relaxes slightly; the locking element is arrested there in its locking position. Then the spring is clamped between the first sleeve and the head of the bolt .

Due to the fixing of the retaining element against rotation in the mounting plate it is no longer necessary to use a tool to restrain the retaining element with a second tool.

The disassembly of the fastening arrangement for the purpose of inverting or replacing the blades is performed by rotating the head of the bolt in the opposite direction (in FIG. 2 in the clockwise direction), where it is possible to bring the locking element out of the locking position against the force of the spring without any excessive torque, due to the relatively small depth of the recess and/or a corresponding chamfer of the helically-shaped surface in the region adjoining the recess . A tool to compress the spring or to immobilize the retaining element is not required. Due to the simple disassembly and assembly of the blades it becomes possible to replace them on the field in case of damage during the harvest. Then the bolt can be removed from the retaining element , as soon as the locking element is located over the region of the opening associated with it.

In the assembled condition of the fastening arrangement the recess has the effect of arresting the locking element in the locking position. The straw chopper can be operated normally. The blades are suspended pendulously on the sleeves and . Since the sleeves and are fixed against rotation on the retaining element , they do not rotate along with the blades . Thereby they cannot rotate or jerk the locking element out of the recess .

FIGS. 4-6 show a second embodiment of a fastening arrangement according to the invention. Elements that conform to the first embodiment are characterized by the same number call-outs.

The second embodiment agrees generally with the first embodiment. There are, however, two differences worth noting. Only one sleeve is provided. On the side of the mounting plate facing the head a second spacer is provided (in place of the sleeve of the first embodiment). The blade hole of the blade , shown at the left in FIG. 4, is located on a circular cylindrical section that adjoins the head of the retaining element , as can best be seen in FIG. . Such a configuration can also be used in the embodiment with elliptical cross sections. It would also be conceivable to provide only two spacers but no sleeve on the side of the mounting plate facing the head of the bolt .

The cross sections of the elements used for the attachment of the retaining element , so that it is fixed against rotation to the mounting plate , that is, the plate hole of the mounting plate and the shank of the retaining element are not elliptical but square. The sleeve and the spacers are also provided with square holes.

The mounting plate , sleeves and spacers of both embodiments can be manufactured at low cost by stamping. Any desirable non-circular cross sections can be used in place of the elliptical or square cross sections of the shank of the retaining element and the plate hole of the mounting plate , as well as the sleeves and spacers . In that way a depression or projection extending axially in the shank of the retaining element would be conceivable, that interact with projecting or depressed regions of the other components named. The insertion of a feather key or another, separate component in a recess of the retaining element would be conceivable for the production of an arrangement, fixed against rotation, of the retaining element in the mounting plate .

Having described the illustrated embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a semi-schematic side view of a harvesting machine with a straw chopper.

FIG. 2 is an exploded perspective view of a first embodiment of a fastening arrangement for the blades of the straw chopper.

FIG. 3 is an enlarged perspective view of the retaining element of FIG. .

FIG. 4 is an exploded perspective view of a second embodiment of a fastening arrangement for the blades of the straw chopper.

FIG. 5 is an enlarged perspective view of the retaining element of FIG. 4 from the outside.

FIG. 6 is an enlarged perspective view of the retaining element of FIG. 4 from the inside.

CLAIMS

1. In combination with a chopper assembly for a harvesting machine, a fastening arrangement for fastening a blade to a rotor of the chopper assembly, the blade being pendulously supported on the rotor, the blade having a blade hole and the chopper assembly comprising the rotor and a mounting plate extending from the rotor, the fastening arrangement comprising a bolt that can be inserted into the blade hole in the blade and a plate hole in the mounting plate, the bolt being connected with a retaining element that retains the bolt in the holes, the retaining element can be separated from the bolt wherein the bolt and the retaining element are fixed against rotation by the mounting plate, the retaining element is inserted into the plate hole in the mounting plate and at least a portion of the retaining element that is inserted into the plate hole and the plate hole are provided with matching non-circular cross sections.

2. In combination with the chopper assembly for a harvesting machine and the fastening arrangement as defined by claim 1, wherein the bolt extends through an axial opening in the retaining element.

3. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 2, wherein the blade is pendulously supported in bearings on the outer circumference of the retaining element surrounding the bolt.

4. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 2, wherein the blade is pendulously supported in bearings on a sleeve surrounding the bolt.

5. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 4, wherein the sleeve is connected to the mounting plate and fixed against rotation by the mounting plate.

6. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 2, wherein the bolt and the retaining element that can be moved between a release position and a locking position by a rotation of less than 360 degrees.

7. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 6, wherein the bolt and the retaining element are retained in the locked position by a spring.

8. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 7, wherein a locking element is connected to the bolt and extends radially from the bolt and can be brought into contact with a helically-shaped surface on the retaining element, which is shaped in such a way that the spring is loaded into the locking position when the locking element is rotated relative to the retaining element and is unloaded when it is rotated into the release position.

9. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 8, wherein the locking element that is located in a recess of the helically-shaped surface in the locking position.

10. In combination with the chopper assembly for the harvesting machine and the fastening arrangement as defined by claim 8, wherein the locking element is rigidly connected to the bolt and the bolt with the locking element are inserted through the axial opening in the retaining element.

11. A straw chopper for a harvesting machine, the straw chopper comprising: a rotor having a plurality of outwardly extending mounting plates, each of the mounting plates having a non-circular plate hole; a plurality of blades pendulously supported from the mounting plates, the blades being coupled to the mounting plates by a fastening assembly, each of the blades having a circular blade hole; the fastening arrangement comprising a bolt that can be inserted into the blade hole in the blade and the plate hole in the mounting plate, the bolt being connected with a retaining element that retains the bolt in the holes, the retaining element can be separated from the bolt, wherein the bolt and the retaining element are fixed against rotation by the plate hole of the mounting plate.

12. A straw chopper as defined by claim 11 wherein the retaining element is inserted into the plate hole in the mounting plate and that at least a portion of the retaining element that is inserted in to the plate hole and the plate hole are provided, with matching non-circular cross sections.

13. A straw chopper as defined by claim 12 wherein the bolt extends through an axial opening in the retaining element.

14. A straw chopper as defined by claim 13 wherein the blade is pendulously supported in bearings on the outer circumference of the retaining element surrounding the bolt.

15. A straw chopper as defined by claim 13 wherein the blade is pendulously supported in bearings on a sleeve surrounding the bolt.

16. A straw chopper as defined by claim 15 wherein the sleeve is connected to the mounting plate and fixed against rotation by the mounting plate.

17. A straw chopper as defined by claim 13 wherein the bolt and the retaining element can be moved between a release position and a locking position by rotating the bolt relative to the retaining element.

18. A straw chopper as defined by claim 17 wherein the bolt and the retaining element are retained in the locked position by a spring.

19. A straw chopper as defined by claim 18 wherein a locking element is connected to the bolt and extends radially from the bolt and can be brought into contact with a helically-shaped surface on the retaining element, which is shaped in such a way that the spring is loaded into the locking position when the locking element is rotated relative to the retaining element and is unloaded when it is rotated into the release position.

COPYRIGHT

User acknowledges that Fairview Research and its third party providers retain all right, title and interest in and to this xml under applicable copyright laws. User acquires no ownership rights to this xml including but not limited to its format. User hereby accepts the terms and conditions of the License Agreement.