Abstract:
A rotor for a bagging machine used to force feed material, e.g., silage, for compaction in a tunnel of the machine prior to insertion of the material into a large storage bag. The rotor includes teeth sets closely spaced along the length of the rotor and each teeth set including at least three circumferentially spaced teeth. Preferably the teeth of each teeth set are intregal with a support or base ring that slidably fits en elongate pipe or tube and position axially in circumferentially as desired and then weld tacked to the pipe.

Description:
FIELD OF INVENTION 
     This invention relates to that component of a bagging machine that forcibly moves material to be bagged, e.g. silage, from a receiving bin or conveyor into the machine tunnel wherein the material is compacted prior to being inserted into a bag. 
     BACKGROUND OF THE INVENTION 
     It is desirable to maximize the compaction of material, e.g. silage, stored in a storage bag to more effectively utilize the capacity of the bag and to dispel air/oxygen that enhances undesired spoilage of the bagged material. Such compaction is achieved by a compacting rotor that is mounted at a restricted inlet of the machine&#39;s tunnel. The rotor is a cylinder or pipe that has teeth mounted on the pipe surface in a prescribed pattern. Material is directed toward the inlet and the teeth of the rotor grab the material and force it rearward through the inlet and into the tunnel and toward the tunnel outlet. The outlet of the tunnel (inlet to the bag) is effectively blocked (material movement is resisted) until a sufficient force is applied. The material is accordingly compacted in the tunnel until the rearward thrust imparted by the rotor overcomes the resistance, moves the machine forward to deploy an incremental length of the bag, and the compacted material is thereby moved into the bag. 
     The bag is sized to fit the cross section of the tunnel and theoretically the material is moved as a compacted cylindrically shaped continuous block of the material that slides into the bag and fills the bag to its capacity. In actual experience, for any of a variety of reasons, the bag is not filled to capacity. Further, it has been learned that certain sizes of the bags, e.g., smaller sizes, will fill to capacity more effectively than the larger sizes. Whereas the rotors have been increased in size and power and speed to accommodate the larger machines for filling the larger bags, the non-capacity filling for the larger bags has persisted and a different answer to the problem was needed. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The present invention is directed to the above mentioned prescribed pattern of the teeth. The teeth are presently secured to a steel pipe having a length of about 90 inches and spans the width of the inlet to the tunnel. The teeth are spaced along the pipe at one-inch intervals and each position has a pair of opposing teeth, i.e., 180 degrees apart. Sequentially, each subsequent pair of teeth are offset circumferentially by about 12 degrees. A more complete explanation of one type of rotor arrangement is explained in the commonly owned U.S. Pat. No. 5,159,877, the disclosure of which is incorporated herein by reference. 
     The material that is commonly bagged is silage which is moist and congeals into clumps of material. Feeder bars overlying the inlet rotate to break up the clumps in part. Nevertheless, there remains at least smaller congealed masses of material that are fed into the rotor which further breaks up these masses, i.e., clumps, as they are engaged by the rotor teeth. 
     It is theorized that the material that is passed through the inlet and into the tunnel for compaction nevertheless still remains at least partially in smaller clumps/masses of material. It is further theorized that these clumps, when compacted together, nevertheless result in spaces interposed between the clumps. For the larger machines, these spaces are larger and when inserted into the bag, followed by settling of the material, the material volume becomes undersized for the available capacity of the bag. 
     The solution of the present invention is to reduce the spaces between the rotor teeth to thereby further restrict the openings through which material is conveyed through the inlet, thus further reducing the size of the clumps being conveyed and thereby enabling greater compaction in the tunnel and as inserted into the bag. This is accomplished in the preferred embodiment by adding a tooth at each of the positions along the rotor length, i.e., three teeth at 120 degree intervals rather than two teeth at 180 degree intervals. 
     A rotor having the three teeth per position arrangement has been built and tested and indeed the compaction of the material as placed in the bag is improved. 
     A further improvement of the invention is in the manufacture of the rotor. Whereas the prior two teeth arrangement involved the fabrication of individual teeth that were then each tacked (by welding) to the outer surface of the pipe, the three tooth arrangement is formed as a single component, i.e., a ring having radial teeth that slide as a unit along the pipe circumference. Thus, a ring and the three teeth arrangement are cut from a single plate. The ring is slid into position on the pipe and a single welding tack may be applied to secure the three teeth in the desired location. 
     The invention will be more clearly understood and appreciated upon reference to the following detailed description and the drawings referred to therein. 
    
    
     
       DESCRIPTION OF THE FIGURES 
         FIG. 1  illustrates a bagging machine incorporating a feed rotor of the present invention; 
         FIG. 2  is a schematic side view of the machine of  FIG. 1  illustrating the manner by which the feed rotor feeds and compacts the material being bagged; 
         FIG. 3  is a side view of a three-tooth segment as applied to the feed rotor of  FIG. 1 ; 
         FIG. 4  is a perspective view of the three-teeth segment of  FIG. 3 ; 
         FIG. 5  is an end view of the feed rotor of  FIG. 1 ; 
         FIG. 6  is a partial side view of the feed rotor of  FIG. 5 ; and 
         FIGS. 7-10  illustrate variations to the mounting of teeth to a rotor. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIGS. 1 and 2  illustrate a bagging machine  10  as is typical of bagging machines used to fill a large flexible bag shown in phantom and indicated by reference number  12 . Such bags  12  are mounted in folded condition (accordion-type fold) to the exterior of the tunnel  14  and is deployed incrementally as material is force-fed into the bag. As seen in  FIG. 1 , a backstop  16  is secured by cables  18  to cable drums  20  on machine  10  and the cables are resistively reeled out (resisted by a brake mechanism) to permit deployment of the bag. Pressure to overcome the brake resistance is applied by the closed end  13  of the bag being forced outwardly as material is fed into the bag which will now be explained. 
     A feed rotor  22  is shown in both  FIGS. 1 and 2 , but the reader is particularly referred to the schematic side view illustration of FIG.  2 . As illustrated in  FIG. 2 , a restricted inlet  24  is defined by the back-lower end of tunnel  14  and the tunnel floor  26 . The feed rotor  22  is positioned adjacent to the inlet and is rotated to grab and direct material being fed by conveyor  28  toward the feed rotor as indicated by directional arrows  30 , and from the feed rotor through the inlet  24  and into the tunnel  14  as indicated by arrows  30 ′. 
     In operation, material to be bagged (reference  32 ) is moved by e.g., the conveyor  28 , which first engages beater bars  34  and is then directed into the teeth  36 . The teeth  36  rotate (counter-clockwise as seen in  FIG. 2 ) to force-feed the material through the inlet  24  and into the tunnel  14 . The bag end  13  and backstop  16  is initially adjacent the end opening  38  and material  32  is fed into the tunnel and against the bag end  13  and backstop  16 . The bag end  13  is prevented from pushing away from the opening  38  by the cables  18 . The material fills the tunnel  14  to a compacted state and continued rotation of the rotor  22  generates a reverse force against the tunnel until sufficient pressure is applied to the backstop  16  to overcome the brake resistance of cable drums  20  (see FIG.  1 ). At that point the cable drum releases additional cable  18  and the machine  10  moves away from the backstop and such produces incremental deployment of bag  12  from the tunnel  14 . Accordingly, material  22  in the tunnel  14  is incrementally moved through the end opening  38  and into the bag  12 . 
     Whereas the above procedure theoretically produces compaction of the material, first in the tunnel and then in the bag to fill the bag (the bag being sized according to the tunnel size) whereby the bag should closely confine the material and alleviate bag slack and the presence of air. Experience has revealed, however, that the material settles and undesired bag slack does occur, particularly in the larger sizes of bags, e.g., 10 to 16 feet in diameter. 
     Whereas the bag&#39;s slack has been largely accepted as unavoidable for the larger sized bags, e.g., of silage material, it has not been accepted as satisfactory. In the course of trying a variety of modifications, a change to the feed rotor unexpectedly has resulted in a desirable improvement to compaction which is now explained. 
     As will be noted from  FIGS. 1 ,  2 ,  5  and  6  (and as explained in the above noted &#39;877 patent), the feed rotor  22  is comprised of a center pipe  40  to which is affixed a pattern of radially extended teeth  42 . The teeth are provided as individual segments  44  as best seen in  FIGS. 3 and 4 . Each segment is a base ring  46  with teeth  42  intregal with and radially extended from the ring  46 . The inner diameter of the center opening  48  matches the outer diameter of the pipe  40  ( FIG. 5 ) and thus the ring  46  can be slid onto the pipe from one end and positioned both axially and circumferentially as desired. Many such segments  44  are mounted to the pipe and welded into place. 
     It is desirable to offset adjacent segments circumferentially to form a pattern of teeth whereby the engagement with the material is essentially continuous while feeding incremental portions of the materials into and through the inlet  24 . As known to the industry and as illustrated in  FIG. 6 , fixed stripper bars  50  (shown in dash line) are positioned above the inlet  24  and fit between the teeth  42  to strip away material that is carried up and back over the rotor. 
     From  FIGS. 3-5 , it will be noted that each segment  44  carries three equally spaced teeth  42 . The leading edge of each tooth is provided with a wear strip  52  which can be replaced as needed. As seen in  FIG. 6 , the spacing between the segments  44  is about equal to the teeth width, e.g., one inch. 
     The rotor of the invention as provided with a three-teeth arrangement, even when slowed as compared to the prior two-teeth arrangement, produces a faster fill rate with less power. More importantly, the three-teeth arrangement provides better compaction of the material in the tunnel and thus in the bag. This result is not fully understood but is believed to be generated by the reduced size of the pocket that is formed between the segments. Each tooth, in conjunction with the side walls of adjacent teeth, acts like a fast-moving bucket that engages and tears away a portion of the material. These are smaller buckets than previously, due to the closer spacing circumferentially, but there are more of them and material is fed into the tunnel as rapidly or even more rapidly but as smaller clumps. The smaller clumps compact in the tunnel with reduced interstices that otherwise form when compacting the larger clumps. Thus, there is less settling and less bag slack and higher percentage of material per bag capacity. 
       FIGS. 7-9  illustrate variations in the manner of securement of the teeth segments to the rotor pipe. In  FIG. 7 , the pipe  54  is square shaped and a square shaped opening  57  of teeth segment  56  allows the teeth segment to be fixed circumferentially relative to the rotor pipe without spot welding. The teeth may be separated by a spacer  58 .  FIG. 8  is a further variation with grooves  62  formed in a cylindrical pipe  60  and the teeth segment  63  and spacer  66  provided with tabs  64  and  65  respectively that fit the groove  66  which permit relative sliding and not rotative sliding of the segments on the pipe.  FIG. 8  illustrates a trapezoidal slot  68  formed in shaft  66  with segment  70  having tangs  21  that fit the slot. Spacers  72  are similarly configured. 
     In all these cases, the shafts  54 ,  60 , 66  may be twisted (or the grooves  62 ,  68  twisted relative to the shaft) to achieve the desired circumferential offset of adjacent teeth sets. Alternatively, the teeth sets may be varied as to the circumferential location of the opening  57 , tab  64  or tang  71  relative to the teeth. A further embodiment is illustrated in  FIG. 10  wherein the pipe or shaft is provided with closely spaced grooves and the teeth segment  76  has widely spaced apart groove fitting teeth that permit adjustment of the segment  76  rotatively relative to each other. 
     Those in the art will conceive of modifications and variations as compared to the disclosed embodiment herein. The claims are not limited to the enclosed embodiment but include all such modifications and variations that are encompassed by a broad interpretation of the claims appended hereto.