Abstract:
A loader stores and loads round objects is presented. The loader includes a screw and a drive tube. The screw has a helical groove. The helical groove winds in a first direction. The drive tube has multiple helical grooves on an inner surface of the drive tube. The multiple helical grooves wind in a second direction. The second direction is counter to the first direction. The screw is located within a center of the drive tube along a length of the drive tube so that round objects loaded within the drive tube are each within the helical groove of the screw and within one of the multiple helical grooves on the inner surface of the drive tube. When the drive tube rotates with respect to the screw, round objects within the drive tube are constrained to travel along the helical groove of the screw and along one of the multiple helical grooves on the inner surface of the drive tube.

Description:
BACKGROUND 
   The present invention pertains to feeders for round objects and pertains particularly to a multiple helical feeder. 
   Paintball guns are used in games where participants fire at one another projectiles consisting of paint enclosed in an outer layer composed of gel. The paintball guns use pressurized gas to propel paintballs towards an intended target. 
   Generally, paintballs are stored in a bulk loader. The bulk loader typically sits on top of the paintball gun and utilizes gravity to feed paintballs into the barrel of paintball gun in preparation for firing at a target. Paintball guns are typically semiautomatic and can be fired as fast as a user can pull a trigger. It is necessary, therefore, for bulk loaders to allow for quick and consistent loading of paintballs. 
   It is not unusual for paint ball guns to occasionally jam during operation. This can often be remedied, for example by a user shaking the gun upon detecting that a jam has occurred. Alternatively, efforts have been made to place anti-jamming devices within paintball loaders. See, for example, U.S. Pat. No. 5,282,454 issued to Roderick L. Bell, et al. on Feb. 1, 1994 and U.S. Pat. No. 6,415,781 B1 issued to Aldo Perrone on Jul. 9, 2002. 
   SUMMARY OF THE INVENTION 
   In accordance with a preferred embodiment of the present invention, a loader for storing and loading round objects is presented. The loader includes a screw and a drive tube. The screw has a helical groove. The helical groove winds in a first direction. The drive tube has multiple helical grooves on an inner surface of the drive tube. The multiple helical grooves wind in a second direction. The second direction is counter to the first direction. The screw is located within a center of the drive tube along a length of the drive tube so that round objects loaded within the drive tube are each within the helical groove of the screw and within one of the multiple helical grooves on the inner surface of the drive tube. When the drive tube rotates with respect to the screw, round objects within the drive tube are constrained to travel along the helical groove of the screw and along one of the multiple helical grooves on the inner surface of the drive tube. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows an example of a paintball gun with a prior art bulk loader. 
       FIG. 2  shows a paintball gun with a paintball loader in accordance with a preferred embodiment of the present invention. 
       FIG. 3  shows an assembled paintball clip separated from a paintball transportation system in accordance with a preferred embodiment of the present invention. 
       FIG. 4  shows a disassembled paintball transportation system in accordance with a preferred embodiment of the present invention. 
       FIG. 5  shows a disassembled paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 6  shows paintballs arranged in an outer cap of a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 7  shows a partially assembled paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 8  shows inner cap of a paintball clip attached to a spring in accordance with a preferred embodiment of the present invention. 
       FIG. 9  shows a screw of a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 10  shows a drive tube of a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 11  and  FIG. 12  are cut-away views illustrating operation of a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 13  is another cut-away view illustrating operation of a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 14  shows a side view of a multiple helix arrangement of paintballs illustrating the way paintballs are stored in a paintball clip in accordance with a preferred embodiment of the present invention. 
       FIG. 15  shows a top view of the multiple helix arrangement of paintballs shown in  FIG. 13  in accordance with a preferred embodiment of the present invention. 
       FIG. 16  shows a close-up of rotation limiter in accordance with a preferred embodiment of the present invention. 
       FIG. 17  shows an outer cap, fitted on a containment tube, having multiple ejection holes in accordance with an alternative embodiment of the present invention. 
       FIG. 18  shows a screw having multiple ridges in accordance with an alternative embodiment of the present invention. 
       FIG. 19  shows a drive tube with straight ridges in accordance with an alternative embodiment of the present invention. 
       FIG. 20  shows an outer cap fitted on a containment tube and having an alternative ejection hole location in accordance with an alternative embodiment of the present invention. 
       FIG. 21  shows a screw in accordance with an alternative embodiment of the present invention. 
       FIG. 22  shows an inner cap with multiple exit holes in accordance with an alternative embodiment of the present invention. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  is a simplified block diagram of a prior art paintball gun  11 . Paintball gun  11  is equipped with a compressed air container  13  used to supply power to propel paintballs towards a target. Paintballs are stored in a bulk loader  12 . 
     FIG. 2  shows bulk loader  12  being replaced with a paintball loader  21 , attached as shown. 
   Paintball loader  21  is shown in  FIG. 3 . An attachment mechanism  35  is used to physically secure paintball loader  21  to paintball gun  11 . Paintballs are stored in a paintball clip  33 . During a firing session, paintballs exit paintball clip  33  and travel through a delivery tube  34  before loaded through an elbow joint  31  into paintball gun  11 . A clip holder  32  secures paintball clip  33  in place during use. Clip holder  32  has a quick release to allow quick and efficient exchange of paintball clips. As further discussed below, a pin  36  within clip holder  32  is used to disengage a spring restraint within paintball clip  33  when paintball clip  33  is attached to clip holder  32 . 
   As shown in  FIG. 3 , the exterior of paintball clip  33  includes an outer cap  56  and a containment tube  51 . When paintball clip  33  is attached to clip holder  32 , clip holder  32  holds outer cap  56 , and thus containment tube  51 , firmly, preventing disengagement or rotation of outer cap  56  and containment tube  51 . 
     FIG. 4  shows detail about how delivery tube  34  is attached to elbow joint  31  and clip holder  32 . Paintballs  45  are shown as they would exit from elbow joint  31 . 
     FIG. 5  shows the disassembled parts of paintball clip  21 . The parts include a containment tube  51 , a drive tube  52 , a screw  53 , a torsion spring  54 , an inner cap  55  and an outer cap  56 . Torsion spring  54  is used to store torsion energy. A compression spring  63  is used to store compression energy between screw  54  and thrust bushing  64 . Torsion spring  54  is attached to inner cap  55  at a square end  57 . 
   Torsion spring  54  fits within screw  53 . When paintball clip  51  is assembled, a square end  59  of torsion spring  54  along with a square shaft  60  of screw  53 , extends through a hole  61  in drive tube  52  and is attached to containment tube  51 . This anchors screw  53  and square end  59  of torsion spring  54  to containment tube  51 . Also, when paintball clip  51  is assembled, inner cap is  55  is attached to drive tube  52  and outer cap  56  is attached to containment tube  51 . Screw  53  has a single ridge  92  that forms a single groove (channel)  192  along which paintballs travel until a ridge tip  65  is reached. 
   When paintball clip  51  is assembled and attached to clip holder  32 , pin  36  (shown in  FIG. 11 ) pushes inner cap  52 , causing compression spring  63  to compress. The resulting alignment of inner cap  55  to outer cap  56  allows rotation of inner cap  55  and drive tube  52  with respect to outer cap  56  and containment tube  51 . Drive tube  52  is driven by the stored torsional energy of torsion spring  54 . A rotation limiter  62  allows torsion spring  54  to remain prewound to an initial tension allowing optimal performance of torsion spring  54 . 
   When paintball clip  51  is filled with paintballs, it is the rotation of inner cap  55  and drive tube  52  with respect to outer cap  56  and containment tube  51  that moves paintballs out of paintball clip  51  and into delivery tube  34  (shown in  FIG. 4 ). 
     FIG. 6  illustrates the path paintballs  45  take when exiting paintball clip  33  through outer cap  56 . Paintballs  45  follow ramp  69  around the diameter of outer cap  56  before exiting through a hole  68 . 
     FIG. 7  shows paintball clip  33  being partially assembled. Within drive tube  52 , paintballs  45  travel around screw  53 , proceed through one of six openings  71  in inner cap  55  and through  68  within outer cap  56 . 
     FIG. 8  shows the arrangement of holes  71  in inner cap  55 . Associated with each hole  71  is a flute denoted by ridges  72  which guide paint balls through holes  71 . 
     FIG. 9  shows screw  53  having a single ridge  92  forming a single groove (channel)  192  along which paintballs travel. Square shaft  60  and ridge tip  65  are also shown. 
     FIG. 10  shows drive tube  52  having six inner ridges  91  that form six grooves (channels)  191  along which paintballs travel. 
   As inner cap  55  (shown in  FIG. 5 ) and drive tube  52  rotate with respect to screw  53  (shown in  FIG. 9 ), outer cap  56  (shown in  FIG. 5 ) and containment tube  51  (shown in  FIG. 5 ), ridges  91  of grooves  191  of inner cap  55  push paintballs  45  (shown in  FIG. 7 ) along groove  192  (shown in  FIG. 9 ) of screw  53  (shown in  FIG. 9 ). 
     FIG. 11  is a cut-away portion of paintball clip  33  and clip holder  32 . Outer cap  56  is shown having been snapped over containment tube  51 . Inner cap  55  is shown having been snapped within drive tube  52 . Square end  59  of torsion spring  54  fits snugly within square shaft  60  of screw  53 . A square feature  133  of containment tube  51  also fits snugly into square shaft  60  of screw  53 . Square end  57  of torsion spring  54  fits snugly within square shaft  66  of inner cap  55 . 
   Torsion spring  54  within screw  53  rotates inner cap  55  and drive tube  52  with respect to screw  53 , outer cap  56  and containment tube  51 . The six grooves  191  in drive tube  52  are aligned with the six flutes on inner cap  55 . 
   In  FIG. 11 , drive tube  52  is in a locked position with respect to containment tube  51 . In the locked position a notch  113  of outer cap  56  is engaged. In  FIG. 12 , drive tube  52  is in an unlocked position with respect to containment tube  51 . In the unlocked position, as evidenced by a space  114 , drive tube  52  is pushed slightly deeper into containment tube  51 , allowing drive tube  52  to allow rotation around pin  36  with respect to containment tube  51 . In the unlocked position notch  113  of outer cap  56  is disengaged. Screw  53  rotates in synchronization with containment tube  51  so that the six grooves  191  are used to guide paintballs  45  along groove  192  of screw  53 , allowing paintballs to exit drive tube  51 . 
   As shown in  FIG. 13 , the flutes bordered by ridges  72  guide paintballs  45  out holes  71  of inner cap  55 , along ejection ramp  69 , out of ejection hole  68  of outer cap  56  and into feed delivery tube  34 . 
     FIG. 14  shows a side view of the multiple column arrangement of paintballs within paintball clip  33 . Lines  131  represent the alignment of paintballs  45  along groove  192  of screw  53  (shown in  FIG. 9 ). Lines  132  represent the alignment of paintballs  45  along grooves  191  of drive tube  52  (shown in  FIG. 10 ). 
     FIG. 15  shows a top view of the multiple column arrangement of paintballs  45  within paintball clip  33 . Hole  130  is the location of screw  53  in relation to the multiple column arrangement of paintballs  45 . 
   The multiple column arrangement of paintballs  45  allows for a significantly reduced amount of work (distance times friction) as the balls travel through paintball clip  33 . This is because, as paintballs  45  travel around groove  192  of screw  53 , the paintballs are divided into six helical columns, divided by six grooves  191  that simultaneously advance paintballs  45  with respect to drive tube  52 . As the paintballs  45  advance along the helix formed by ridge  92 , paintballs  45  simultaneously advance along the six columns formed by grooves  191 . The resulting shorter path paintballs  45  travel with respect to drive tube  52  results in minimal work (distance times friction) as paintballs  45  advance within drive tube  52 . 
     FIG. 16  shows a close-up of rotation limiter  62 . 
   Various alternative embodiments of the invention can also be utilized. For example, instead of a single ejection hole in the outer cap, multiple ejection holes can be used. This is illustrated in  FIG. 17  where an outer cap  203 , fitted on a containment tube  202 , has multiple ejection holes  204  which are used to eject paintballs. 
   For example, the screw can have multiple ridges and multiple grooves instead of a single ridge and a single groove. This is illustrated in  FIG. 18  where a screw  220  is shown to have a ridge  221  with a ridge tip  223 , and a ridge  222  with a ridge tip  224 . Ridge  221  and ridge  222  form two separate grooves: a grove  225  and a groove  226 . 
   In another alternative embodiment of the present invention, the ridges of drive tube can be straight lines resulting in vertical columns. This is illustrated in  FIG. 19  where ridges  221  of a drive tube  220  are straight. Nevertheless, in the preferred embodiments, the ridges are helical in form as shown in  FIG. 10 . This allows for more efficient packing of paintballs  45  within paintball clip  33 . Specifically, the slope of ridges  91  (shown in  FIG. 10 ) on drive tube  52  is selected so that each row of paintballs  45  around ridge  92  interlocks with the previous row and the following row of paintballs around ridge  92 . This can be seen in the resulting interlocking pattern of paintballs  45  shown in  FIG. 13 . 
   In other alternative embodiments, the containment tube can be eliminated and the screw can be rotated with respect to a drive tube having helical (or straight) grooves as described herein. It is intended that the statement “the screw rotates with respect to the drive tube” is equivalent to the statement “the drive tube rotates with respect to the screw”. 
     FIG. 20  shows an embodiment of the present invention with an outer cap  231  fitted over a containment tube  230 . A drive tube (similar to drive tube  52  shown in  FIG. 5 ) rotates with respect to a screw  233 , shown in  FIG. 21 . An inner cap  240 , shown in  FIG. 22 , has multiple exits holes  241 . In this embodiment, paintballs travel along a groove  235  of screw  233 , go up a ramp  234  and exit inner cap  240  through one of exit holes  241  and then exits outer cap  231  through a side hole  232 . 
   While in various embodiments of the present invention, a torsion spring is used to power rotation of the drive tube with respect to the screw, other devices can be used to provide power. For example, pressurized gas or an electric motor can be used to power rotation of the drive tube with respect to the screw. It is considered that powering rotation of the drive tube with respect to the screw is equivalent to powering rotation of the screw with respect to the drive tube. Alternatively, the power for rotation of the drive tube with respect to the screw can be supplied manually by a user. 
   The foregoing discussion discloses and describes merely exemplary methods and embodiments of the present invention. As will be understood by those familiar with the art, the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For example, while the preferred embodiment of the present invention is described with regard to loading paintballs into a paintball gun, the ideas presented can be used effectively for loading round objects into any type of device. Accordingly, the disclosure of the present invention is to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.