Abstract:
A bag filling machine having a tunnel and a bag fitted to the tunnel for transferring material compacted in the tunnel and in the compacted state, into the bag. The tunnel is composed of a bottom portion and alternating top portions that are alternatively and selectively secured to the bottom portion. Said top portion defining a portion of the circumferential rear end opening and having different circumferential end portions that adapt the tunnel to different bag sizes.

Description:
FIELD OF THE INVENTION 
     This invention relates to a bagging machine such as used for bagging and the like and more particularly to the convertibility of the machine for bagging into different sized bags. 
     BACKGROUND OF THE INVENTION 
     Bagging machines as contemplated by the present invention are used primarily (but not exclusively) for storage of farm crop materials. A major application is the storage of silage and other materials used for feeding farm animals. In many parts of the country, grass does not grow during the months from late fall to early spring and animal feed such as silage is harvested and stored during the summer and fall months and then removed piece meal for feeding cattle, e.g., dairy cows. 
     The bagging process requires that the crop material be tightly compressed in a heavy non-elastic bag so that there is minimal air and thus oxygen that is retained in the bag that can cause the crop to spoil during storage. 
     When it is necessary to remove the material from the bag for feeding the farm animals, one end of the bag is opened and then day by day a desired portion of the material is removed from the opened bag end and fed to the farm animals. Because the bag is now opened, the end of the material in the bag is exposed to the atmosphere/air (oxygen) and if allowed to be exposed for any length of time, the material in that end of the bag will spoil. 
     It has been learned that the way to avoid spoilage is to remove a sufficient depth of the material each day so that the material previously adjacent the opened end and which has been exposed to air is removed prior to spoilage and the fermenting or spoiling process starts anew with the newly exposed end portion of the material. The newly exposed material will be removed the following day before spoilage can take place and so on. 
     Of course that material which is removed needs to be fed to and eaten by the animals and it is the amount of material required for feeding the animals that dictates the amount of feed that is to be removed from the storage bag. It follows that the bag opening (diameter) is desirably matched to the amount of daily feed required. Thus, if it is determined that the air will penetrate into the material at the opened end of up to 10 inches and therefore at least 10 inches depth of material is desirably removed daily, and it is determined that the daily feed required for feeding the animals is one ton of that material, then the diameter of the bag needs to be no greater than that which will result in the daily removal of 10 inches depth of material without exceeding a ton of the material. 
     Bag sizes (diameter) typically are provided in one foot increments between six and twelve feet in diameter. Prior bagging machines when manufactured were provided with tunnels sized to fit a particular bag size. Thus, if a dairyman has a dairy herd that requires daily feeding of one ton of material, he determined the size of the bag he needed and accordingly acquired a bagging machine that accommodated that bag size. 
     BRIEF DESCRIPTION OF THE INVENTION 
     A problem that occurs is that a farmer/dairyman may have a requirement for more than one bag size. For example, he may want to feed a combination of feed material. He may wish to feed one ton of silage and one and one-half tons of alfalfa which require different bag sizes. In other instances he may want to feed alternating materials having different densities whereby the same one ton of material occupies different volumes. In order to accommodate the different bag sizes, the farmer was previously required to own multiple bagging machines. 
     The present invention provides the ability to convert the same bagging machine to different bag sizes. In brief, a tunnel may be sized to fit a 10 foot diameter bag size. This diameter bag has a circumference of about 31.4 feet. The tunnel circumference at the rear opening is not typically circular and somewhat wider than it is tall. Nevertheless, the circumference is substantially 31.4 feet and the flexible bag just fits over the tunnel end opening. The material that is first compressed in the tunnel and then forced into the bag substantially fills the entire bag cross section. 
     To convert the tunnel so as to fit a 9 foot bag, the circumference of the tunnel end opening needs to be about 28.3 feet in circumference. To achieve this, the approximate upper half or top of the tunnel is a bolt on section. By unbolting the upper half and replacing it with a tunnel top that has the same configuration in the horizontal plane but shorter in height, the overall circumference of the tunnel end opening is reduced. The replacement top is designed to fit directly onto the tunnel bottom and thus configured in that respect like the prior 10 foot tunnel top. The outer perimeter of the inverted U-shaped upper half of the mouth of the end opening is reduced by the difference in circumference between a 10 foot bag opening and a 9 foot bag opening or substantially by about 3.1 feet. Now a 9 foot bag will precisely fit the new tunnel configuration. 
     The invention and the benefits of the invention will be more fully appreciated upon reference to the following detailed description having reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 schematically illustrates a bagging machine in the process of inserting feed material into a bag for which the present invention is contemplated; 
     FIG. 2 is a view as if taken on view lines  2 — 2  of FIG.  1  and having replaceable tunnel top portions in accordance with the present invention; 
     FIG. 3 is a comparison of alternative first and second tunnel top portions for the tunnel bottom of FIG. 2; 
     FIG. 4 is a rear end view of the first tunnel top portion; 
     FIG. 5 is a side view as taken on view lines  5 — 5  of FIG. 4; 
     FIG. 6 is a rear end view of the second tunnel top portion; 
     FIG. 7 is a side view as taken on view lines  7 — 7  of FIG. 6; 
     FIG. 8 is a rear view of a tunnel bottom portion; and 
     FIG. 9 is a side view of the tunnel bottom portion as taken on view lines  9 — 9  of FIG.  8 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 schematically illustrates a bagging machine, e.g., for bagging silage incorporating the present invention. Silage material indicated by arrow  10  is deposited in a hopper  12  forming part of the machine. The material  10  is force fed from the hopper by a rotor  14  and into a tunnel  16 . The tunnel  16  has an open end  18  at the rear of the tunnel and a bag  20  having a gathered portion  22  and a filled or deployed portion  24  mounted over the open end  18  to receive material  10 . The material  10  is first compacted in the tunnel  16  and then shoved into the deployed portion of the bag due to the force feeding by the rotor  14 . As the deployed portion becomes satisfactorily compacted in the bag portion  24  and because the bag portion is stationary, the back pressure created by the feed pressure of the rotor forces forward movement of the machine and deployment of an additional length of the bag from gathered portion  22  mounted on the tunnel. 
     It will be appreciated that it is important to completely (or nearly completely) fill the bag. This is accomplished by matching the cross section capacity of the tunnel  16  at the discharge or rear end opening  18  of the machine to the cross section capacity of the bag. This insures that throughout the filling process the material in the bag substantially is filled to its capacity. The bag  20  is substantially non-elastic in order to retain the desired compaction. 
     As explained in the Background of the Invention, it is desirable to use different sized bags (cross sectional circumference) depending on the desired material removal rate, i.e., the projected tonnage to be removed daily from the bag once the bag is opened. The invention is enabled by an appreciation that fitting the bag to the tunnel end does not require a particular cross section shape. The tunnel opening can be circular, oval shaped or a modified rectangular shape of varying dimensions. The flexibility of the bag allows the open end of the bag to conform to the tunnel shape. What is important is that the circumferential distance of the bag periphery substantially matches the periphery of the tunnel end opening. 
     With reference to FIG. 2, two different rear end openings,  18  (solid line) and  18 ′ (dash lines), are illustrated. Arrows  26  track a bottom end periphery that is common to both end openings  18  and  18 ′. Arrows  28  track the remaining periphery of end opening  18  and arrows  30  track the remaining periphery of end opening  18 ′. The difference in the peripheries  26 ,  28  and  26 ,  30  is illustrated in FIG.  3 . The upper portions of the end openings  18  and  18 ′ (which portions are tracked by arrows  28  and  30 , respectively) are overlaid in FIG.  3  and have similar peripheries except for the portions designated by arrows  32 . The portions  32  at the two sides, when added together, indicate the difference in the circumferential distance as between end opening  18  and end opening  18 ′. 
     EXAMPLES 
     It will be assumed that the two open ends,  18  and  18 ′, are intended to fit bag sizes of 10 feet and 9 feet, respectively. The 10 foot bag has a periphery of about 31.4 feet and the 9 foot bag a periphery of 28.3 feet. Thus, periphery  26 ,  28  is similar to the 10 foot bag or about 31.4 feet and periphery  26 ,  30  similar to the 9 foot bag or about 28.3 feet. The difference is 3.1 feet which is the summation of distances  32  of FIG.  3 . 
     The above relationship is developed for a preferred embodiment of the invention and, of course, the upper portions  28 ,  30  of ends  18  and  18 ′ do not have to be similarly shaped as shown (the overlaid portions) except for the bottom lateral edge E. At bottom edge E in full cross section, both top portions are similarly configured and have the same lateral dimensions so that both upper portions similarly fit onto the top edge of bottom portion  26 . The additional criteria is, of course, that whatever the configuration of the tunnel, periphery  26 ,  28  is 31.4 feet in total circumference and the periphery  26 ,  30  is 28.3 feet in circumferential distance. 
     Reference is now made to FIGS. 4-9. FIGS. 8 and 9 are rear and side views, respectively, of a bottom portion of the tunnel, i.e., that portion permanently affixed to the bagging machine and indicated by arrows  26  in FIG.  2 . Extended laterally from the top side edges of the bottom section are flanges  34 . FIGS. 4 and 5 illustrate the larger top tunnel portions having peripheries  28  and including flanges  36 . With the top tunnel portion fitted in place to the lower tunnel portion, flanges  34 ,  36  are aligned including bolt holes through the flanges, and bolts  38  (FIG. 4) are inserted through the flanges  34 ,  36  and secured by nuts  40  (FIG. 8) to thereby clamp the tunnel portions together. 
     The tunnel when fitted with the larger top tunnel portion is accordingly adapted to receive a 10 foot bag and when a 9 foot bag is preferred, the bolts  38  are removed and the smaller top tunnel portion of FIGS. 6 and 7 is fitted to the bottom tunnel portion with flanges  36 ′ aligned with flanges  34  of the bottom section (FIGS.  8  and  9 ). The bolts  38 ′ are inserted through the flange openings and the tunnel is now adapted to receive a 9 foot bag. 
     It will be appreciated that the concept of tunnel conversion explained above can be applied to other sizes, i.e., converting the tunnel to fit a 9 foot or 8 foot bag, a 7 foot or 8 foot bag or even three or more bag sizes, i.e., a 9 foot standard tunnel shape being enlarged to fit a 10 foot bag and reduced to fit an 8 foot bag. 
     Those skilled in the art will likely conceive of numerous modifications and variations of the illustrated embodiment without departing from the intended scope of the invention. The invention is accordingly defined by the claims appended hereto.