BRIEF DESCRIPTION OF THE DRAWINGS
The detailed description of the drawings refers to the accompanying figures in which:
FIG. 1 is a side elevation view of a round baler comprising a plurality of roller assemblies about which bale-forming belt(s) are trained;
FIG. 2 is a perspective view showing mounting of an end of a roller assembly of FIG. 1 to a wall of the baler housing;
FIG. 3 is an end elevation view of the roller assembly of FIG. 2;
FIG. 4 is a sectional view taken along lines 4-4 of FIG. 3; and
FIG. 5 is a view of an axial alignment guide of the roller assembly.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring to FIG. 1, there is shown a mobile agricultural baler 10 in the form of, for example, a round baler for forming round bales 12. When the baler 10 is advanced along the ground 14 by a vehicle (not shown) via an attachment 16, the baler 10 picks up material from the ground 14 by use of its picker 16 and feeds the material into a chamber 18 of a baler housing 20 of the baler 10. One or more bale-forming belt(s) 22 are trained about a plurality of rotatable roller assemblies 24 for advancement thereabout to form the material into the growing bale 12. Once the bale 12 reaches a desired size, it may be discharged from the baler 12 to make room for formation of another bale.
Each roller assembly 24 is mounted to the baler housing 20 in a manner that avoids transmission of an undue axial load to a bearing of the assembly 24. It is to be understood that the roller assembly 24 discussed in more detail herein may be used with other types of agricultural balers or, more generally, with other types of machines.
Referring to FIGS. 2-4 together and, in particular, FIG. 4, the roller assembly 24 has a shaft 26 about which the belts 22 are trained. Illustratively, the shaft 26 includes a hollow cylindrical belt-engaging roll tube 28 in the chamber 18. The roll tube 28 is mounted at one or both of its ends to a stub shaft 30 by use of a ring plate 32 secured to an inner surface of the roll tube 28 and an outer surface of a disk portion 34 of the stub shaft 30.
An axial portion 36 of the stub shaft has a non-circular cross-section 38 on which a bearing 40 mounted, as shown, for example, in FIGS. 3 and 4. An inner race 42 of the bearing 40 has an inner surface 43 received on and shaped complementary to the non-circular cross-section 38 so as to mate generally therewith, as shown by the phantom lines in FIG. 3. The non-circular cross-section 38 is, for example, hexagonal although a wide variety of multi-faceted or other non-circular shapes are possible. Such a non-circular cross-section 38 enables the roller assembly 24 to provide input and output torque drives without requiring secondary shaft finishing operations such as spline hobbing, etc. It further addresses shortcomings of using bearings with eccentric locking collars on rounds shafts.
A clamp 44 clamps the inner race 42 to the stub shaft 30 for rotation of the inner race 42 with the stub shaft 30 about an axis 41 of the shaft 26. Clamping of the inner race 42 to the stub shaft 30 eliminates or otherwise abates the potential of rotational knock and axial creep between the non-circular cross-section 38 and the bearing 40.
The clamp 44 acts between the stub shaft 30 and opposite sides of the inner races 42 for preventing the inner race 42 from moving either axially or radially relative to the shaft 30. Acting between one side of the inner race 42 (i.e., the right side in FIG. 4) and the disk portion 34 are a chamfered spacer ring 46 and a plurality of shims 48 (e.g., washers), the number of shims 48 being selected to properly axially position the bearing 40 along the axial portion 36 as discussed in more detail below. On the other side of the inner race 42 (i.e., the left side in FIG. 4) are more shims 50 (e.g., washers), a spacer ring 52, and a press plate 54 against which a fastener 56 (e.g., a threaded bolt) acts to clamp the inner race 42 in place via the press plate 54, the shims 48, 50, and the spacer rings 46, 52.
The bearing 40 further includes an outer race 56 that cooperates with the inner race 42 to capture a plurality of rotatable elements 58 (e.g., ball bearings) therebetween. The rotatable elements 58 do not tolerate undue axial loads well. As a result, the bearing 40 is mounted in such a way so as to avoid transmission of undue axial loads to the elements 58, as discussed below.
A bearing housing 58 is disposed about the outer race 56 so as to support the outer race 56 and, in turn, the rest of the bearing 40, the clamp 44, and the shaft 26. The bearing housing 58 has an annular portion 60 and one or more tabs 62. The annular portion 60 surrounds the outer race 56 such that a spherical inner surface of the annular portion 60 mates with a spherical outer surface of the outer race 56.
The tabs 62 extend axially from the annular portion 60 and are spaced circumferentially about the annular portion 60. Exemplarily, there are three tabs 62 (left, right, and center tabs in FIGS. 2 and 3) for mounting of the roller assembly 24, although, in some cases, the number of tabs 62 may be more or less.
A housing attachment unit 63 secures the bearing housing 58 to a mount 65 by a mounting force directed in a plane 71 oriented at right angles to the axis 41. Exemplarily, the housing attachment unit 63 includes a fastener 64 for each tab 62. In the illustrated example, there are three fasteners 64 (left, right, and center fasteners in FIGS. 2 and 3), one respectively associated with each tab 62. Each fastener 64 secures the respective tab 62 to a mounting bracket 67 positioned radially outward from the tab 62 and fixed to a wall 69 of the baler housing 20, the mounting bracket 67 and the wall 69 cooperating to provide the mount 65.
As shown best in FIG. 4 with respect to one of the fasteners 64 (i.e., the center tab), each fastener 64 extends longitudinally in the plane 71 through an opening 66 formed in the tab 62 and an opening 68 formed in the mounting bracket 67 so as to secure the respective tab 62 to the bracket 70 with a mounting force directed in the plane 71. Since each fastener 64 acts in the plane 71 which is at right angles to the axis 41, it does not act axially thereby avoiding transmission of an undue axial load to the bearing 40.
Exemplarily, each fastener 64 is a bolt. In such a case, the fastener 64 may have a threaded shank 76 that extends through the openings 66, 68, a head 78 fixed at one of the shank 76, a washer 80 between the head 78 and the bracket 70, and a nut 82 threadedly secured to the threaded portion of the shank 76.
As shown best in FIGS. 2 and 3, the mounting bracket 67 is, for example, V-shaped. As such, it has diverging left and right arms 84 and a vertex 86 interconnecting the left and right arms 84. The arms 84 and the vertex 86 are fixed to the wall 69. The center tab 62 is secured to the vertex 86 by use of the center fastener 64. The left tab 62 is secured to the left arm 84 by use of the left fastener 64. The right tab 62 is secured to the right arm 84 by use of the right fastener 64.
Each arm 84 has a base portion 88 and a radially flexible, cantilevered portion 90, as shown best in FIG. 2. The base portion 88 is fixed to the wall 69 whereas the radially flexible, cantilevered portion 90 is cantilevered to the base portion 90 at a proximal end of the portion 88 for radial flexure of a free end of the portion 88 upon attachment of the respective tab 62 thereto. The free end of the portion 88 has formed therein the respective opening 68 through which the fastener 64 extends longitudinally therethrough. The portion 90 is flexible to accommodate dimensional variation within the manufacturing tolerances of the associated components.
Referring to FIGS. 2-5 and, in particular, to FIG. 5, the bearing housing 58 includes an axial alignment guide for guiding axial alignment of the bearing housing relative to the mount 65 during assembly of the roller assembly 24. In the illustrated embodiment, the axial alignment guide comprises a step 92 protruding axially from each tab 64 such that an axial dimension 94 of each step 92 defines an axial position range. The bearing housing 58 is positioned such that an edge 96 of the mounting bracket 67 falls within the axial position range 94 defined by each step 92. Alignment of the bearing housing 58 and thus the bearing 42 in this way minimizes the risk of transmission of an undue axial load to the bearing 42.
During assembly, the spacer ring 46 is installed on the stub shaft 36 and enough shims 48 are positioned between the inner race 42 and the ring 46 to align the bearing housing 58 axially such that the mounting bracket edge 96 is located within the axial position range 94 of each step 92. The fasteners 64 are then pre-installed by tightening the fasteners 64 only enough to achieve a light contact between the tabs 62 and the mounting bracket 67. Next, shims 50 and spacer ring 52 are installed on the other side of the inner race 42 after which the fastener 56 is tightened against the press ring 54 so as to clamp the inner race 42 to the stub shaft 30. After the inner race 42 is clamped, tightening of the middle fastener 64 is completed followed by tightening of the left and right fasteners 64, securing the tabs 62 to the mounting bracket 67 with the fasteners 64.
While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. It will be noted that alternative embodiments of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations that incorporate one or more of the features of the present disclosure and fall within the spirit and scope of the present invention as defined by the appended claims.
Patent Application
20080022864
