Patent Publication Number: US-8118015-B2

Title: Bottom feed magazine of paintball gun

Description:
FIELD OF PATENT APPLICATION 
     The present patent application relates to a bottom feed magazine of a paintball gun. 
     BACKGROUND 
     Paintballs are usually fed into a paintball gun by means of a bulky bucket-like hopper that is attached to the top of the main body of the paintball gun. However, this top feed bulky hopper disrupts the player&#39;s view and easily gives away the position of the player by having the bulky hopper sticking out on top of the paintball gun during the game. 
     To resolve the above-mentioned problem, spring-loaded magazines have been designed to feed paintballs from the bottom of the paintball gun. However, these bottom feed spring-loaded magazines are limited in capacity in holding paintballs. Normally, a spring-loaded magazine can only hold up to about 20-30 paintballs. Furthermore, the spring load constantly puts pressure on the paintballs in the magazine causing them to deform and jam. 
     The above description of the background is provided to aid in understanding a bottom feed magazine of a paintball gun, but is not admitted to describe or constitute pertinent prior art to the bottom feed magazine of a paintball gun disclosed in the present patent application. 
     SUMMARY 
     A magazine of a paintball gun is provided. The magazine includes a housing for storing a plurality of paintballs, a channel for receiving the paintballs dropped therein from the housing, a plurality of arms for driving the paintballs along the channel, and a tube having an inlet end extending into the channel and an outlet end extending generally upwards to a top wall of the housing. The paintballs dropped into the channel are driven along the channel, pushed into the inlet end and up along the tube towards the outlet end by the arms. 
     The channel may include an annular channel defined by a circular tray mounted to the housing and a hub rotatable within the circular tray about a central shaft fixed to the hub. 
     The plurality of arms may be provided on the hub and extends radially outwards to define a plurality of slots for receiving the paintballs. 
     The housing may include a partition wall dividing the housing into an upper compartment for storing the paintballs and a lower compartment in which the tray and the hub are mounted, and the partition wall may include an opening through which the paintballs drop from the upper compartment into the channel in the lower compartment. The partition wall may include a slanted portion for directing the paintballs in the upper compartment to roll towards the opening of the partition wall. 
     The tube may include a generally horizontal section, a generally vertical section, and an upturning curved section extending between the horizontal and vertical sections. 
     The housing may sized and shaped for receiving up to 100 or more paintballs. 
     The bottom feed magazine may further include a coupler connected to the outlet end of the tube for detachably coupling the bottom feed magazine to a firing chamber of the paintball gun. 
     The bottom feed magazine may further include a handle fixedly coupled to an end of the shaft of the central hub extending outside the housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Specific embodiments of the bottom feed magazine of a paintball gun disclosed in the present patent application will now be described by way of example with reference to the accompanying drawings wherein: 
         FIG. 1  is a cross sectional view of the bottom feed box magazine of a paintball gun according to an embodiment disclosed in the present patent application; 
         FIG. 2  is a similar cross sectional view of the bottom feed box magazine of a paintball gun in  FIG. 1  showing the initial loading of paintballs in the box magazine; 
         FIG. 3  is a horizontal cross sectional view of the bottom feed box magazine of the paintball gun; 
         FIG. 4  is a cross sectional view of the bottom feed box magazine showing a slide door and a side door in an open position; 
         FIG. 5  is a cross sectional view of the bottom feed box magazine showing the slide door and the side door in a closed position; and 
         FIG. 6  is another cross sectional view of the bottom feed box magazine. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to a preferred embodiment of the bottom feed magazine of a paintball gun disclosed in the present patent application, examples of which are also provided in the following description. Exemplary embodiments of the bottom feed box magazine of a paintball gun disclosed in the present patent application are described in detail, although it will be apparent to those skilled in the relevant art that some features that are not particularly important to an understanding of the bottom feed magazine of a paintball gun may not be shown for the sake of clarity. 
     Furthermore, it should be understood that the bottom feed magazine of a paintball gun disclosed in the present patent application is not limited to the precise embodiments described below and that various changes and modifications thereof may be effected by one skilled in the art without departing from the spirit or scope of the claims. 
     Certain terminology is used in the following description for convenience only and is not limiting. The word “left”, “right”, “upper”, “lower”, “top”, or “bottom” designates directions in the drawings to which reference is made. The terminology includes the words noted above as well as derivatives thereof and words of similar import. 
     It should be noted that throughout the specification and claims herein, when one element is said to be “coupled” or “connected” to another, this does not necessarily mean that one element is fastened, secured, or otherwise attached to another element. Instead, the term “coupled” or “connected” means that one element is either connected directly or indirectly to another element, or is in mechanical or electrical communication with another element. 
       FIG. 1  is a cross sectional view of the bottom feed magazine of a paintball gun according to an embodiment disclosed in the present patent application. 
     The bottom feed magazine includes a housing  10 . According to the illustrated embodiment, the housing  10  may be generally rectangular box-shaped having a top wall  12 , a sidewall  14 , and a bottom wall  16 . The housing  10  may include an upper compartment  20  and a lower compartment  22 , and a petition wall  24  dividing the upper and lower compartments  20 ,  22 . The upper compartment  20  is adapted to receive and store therein a plurality of paintballs B. The upper compartment  20  may have a size sufficient to receive up to 100 or more paintballs B. A slide door  26  can be slidably mounted on the top wall  12  of the housing  10  to cover an upper opening provided on the upper compartment  20  of the housing  10 . An additional side door  28  may be provided on the sidewall  14  of the housing  10 , as shown in  FIGS. 4 and 5 . 
     The housing  10  may be made of plastic or any other suitable material. The housing  10  may be made of transparent material so that a player can see the number of paintballs B remaining in the magazine during the game. 
     Although it has been shown and described that the magazine is generally rectangular box-shaped, it is appreciated that the magazine can be in any other appropriate shape and size. For example, the magazine can be generally cylindrical in shape. 
     The lower compartment  22  includes a circular tray  30  that may be mounted to a lower surface of the partition wall  24 . A circular central wheel or hub  32  can be fixedly mounted on a shaft  34  rotatably mounted at the center of the tray  30 . The central hub  32  may include a circular sidewall  36  with a surface generally conforming in shape with the outer surface of the paintballs B. The circular tray  30  and the central hub  32  together define an annular recess or channel  38  along which paintballs B 1  move. The central hub  38  may include a plurality of paintball-driving protrusions or arms  40  extending radially therefrom for driving paintballs B 1  along the annular channel  38 . Two adjacent paintball-driving arms  40  define a slot  41  for receiving therein a paintball, as best illustrated in  FIG. 3 . 
     Although it has been shown and described that the paintballs are received in the annular channel defined by the circular tray and the central hub, it is understood by one skilled in the art that the paintballs can be received in any suitable form and shape of channel or recess formed separately from or integrally with the housing. 
     The bottom feed magazine may include a paintball-feeding tube  50  having an inlet end  60  extending into the annular channel  38  and an outlet end  62  extending generally upwards to the top wall  12  of the housing  10 . According to the illustrated embodiment, the paintball-feeding tube  50  is generally J-shaped. The paintball-feeding tube  50  may include a generally horizontal section  52 , an upturning curved section  54 , and a generally vertical section  56 . The inlet end  60  is provided on the horizontal section. The outlet end  62  is provided on the vertical section  56 . The outlet end  62  may include a coupler  64  for detachably coupling the bottom feed magazine to a firing chamber of the paintball gun. The paintball-feeding tube  50  can be disposed generally at a center of the housing  10 , as illustrated in  FIGS. 4-6 . This allows the housing  10  to be mounted in a steady and balanced position when the box magazine is attached to the bottom of the paintball gun. 
     An electric motor  68  and a drive mechanism, generally designated by reference numeral  70 , can be employed to drive the shaft  34  to rotate. The drive mechanism  70  may include a first belt-pulley  72  fixedly mounted on a motor shaft  74 , a second belt-pulley  76  fixedly mounted on shaft  78 , and a belt  80  looping over the first and second belt-pulley  72 ,  76  for driving them to rotate simultaneously. The drive mechanism  70  may further include a pinion gear  82  fixedly mounted on the shaft  78 , and a gear  84  fixedly mounted on the shaft  34  and engaged with the pinion gear  82 . The first and second belt-pulleys  72 ,  76  and the two gears  82 ,  84  can be accommodated within a pulley and gear box  86 . 
     Although it has been shown and described that the drive mechanism  70  contains a combination of belt-pulleys and gears, it is understood by one skilled in the art that the drive mechanism can be of any other suitable drive mechanism so long as it can translate the rotating motion of the motor shaft to the rotating motion of the shaft that drives the central hub around. For example, the drive mechanism may only contain a gear train having a plurality of meshing gears, or may only contain a plurality of bell pulleys with at least one belt looping over the bell pulleys. 
     A power source such as a battery  90  may be provided to supply power to the motor  68  through electric wires  92  that are electrically connected to a printed circuit board  94 . A switch may be provided to turn the motor  68  on and off in a conventional manner. When the motor  68  is activated, the motor shaft  74  rotates and drives the first and second belt-pulleys  72 ,  76 , the two gears  82 ,  84 , the shaft  34 , and in turn the central hub  32  to rotate. 
     When the central hub  32  rotates, the paintball-driving arms  40  push the paintballs B 1 , which are dropped into the annular channel  38  from the upper compartment  20 , to move along the annular channel  38  and eventually into the inlet end  60  of the paintball-feeding tube  50 . It is appreciated that the inlet end  60  extends into the annular channel  38  to a certain distance sufficient to take up the paintballs being driven by the arms  40  and yet clear from the moving arms  40 . When a paintball B 2  has been driven into inlet end  60  of the paintball-feeding tube  50 , the paintball B 2  pushes the paintballs already inside the paintball-feeding tube  50  along the horizontal section  52 , up into the upturning and vertical sections  54 ,  56  of the paintball-feeding tube  50 , as shown by the arrows. Eventually, a paintball B 3  originally located at an uppermost position of the vertical section  56  can be pushed into the firing chamber of the paintball gun ready for firing. 
     A handle  100  may be provided within a recess  102  formed on the bottom wall  16  of the housing  10 . The handle  100  may be fixedly mounted at a lower end of the shaft  34  extending outside the housing  10 . The handle  100  may be employed to manually drive the central hub  32  to rotate when necessary. 
       FIG. 2  is a similar cross sectional view of the bottom feed magazine of a paintball gun in  FIG. 1  showing the initial loading of paintballs B in the box magazine. A player can slide the door  26  open and load up to 100 or more paintballs B into the upper compartment  20  of the housing  10 . The petition wall  24  may have a slanted portion  25  for directing the paintballs B to roll by gravity from one side to the other side of the housing  10  where the tray  30  is located. Paintballs B drop into the annular channels  38  of the tray  30  through an opening of the partition wall  24 . Paintball B 1  at one side of the annular channel  38  can be driven by the arms  40  to the other side. Paintball B 2  at the other side of the annular channel  38  can then be pushed into the inlet end  60  of the paintball-feeding tube  50  by the arms  40 . The player can also load the paintballs B into the upper compartment  20  through the side door  28  provided on the sidewall  14 , as depicted in  FIGS. 4 and 5 . 
     While the bottom feed magazine of a paintball gun disclosed in the present patent application has been shown and described with particular references to a number of preferred embodiments thereof, it should be noted that various other changes or modifications may be made without departing from the scope of the appending claims.