Abstract:
A game call having variable tonal qualities wherein one or more sound boards have a ferromagnetic material carried in a selected region and wherein a second ferromagnetic material is mounted for selective movement relative to the ferromagnetic material carried on the sound board to vary the tones created on the sound board.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to the field of hunting and more specifically to apparatus used by hunters and other wildlife enthusiasts to call wild game into their vicinity. More particularly, the present invention relates to the field of box calls generally. In even greater particularity the present invention is a call having a striker and a an plurality of variable pitch sounding plates. 
     SUMMARY OF THE PRESENT INVENTION 
     It is an object of the present invention to enable the hunter to quickly and easily tune his call to the sound of the hens or gobblers in his hunting area. 
     Another object of the invention is to enable the hunter to sound like several different birds while only using one call. 
     Still another object of the invention is to provide a variable pitch call that is simple to use and saves the hunter the necessity of carrying several different calls. 
     These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The game call is depicted in the accompanying drawings which form a portion of this disclosure and wherein: 
         FIG. 1  is a perspective view of an embodiment of a box call having a linearly movable magnet mounted therein; 
         FIG. 2  is a side sectional view of the embodiment illustrated in  FIG. 1 ; 
         FIG. 3  is an end sectional view of the embodiment illustrated in  FIG. 1 . 
         FIG. 4  is a side sectional view of a second embodiment of a box call having a rotatably mounted magnet mounted therein; 
         FIG. 5  is an end sectional view of the embodiment illustrated in  FIG. 4 ; 
         FIG. 6  is a top perspective view of the embodiment shown in  FIG. 5  without the striker plate attached; 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the  FIGS. 1-4  for a clearer understanding of the invention, it may be seen that the preferred embodiment of the invention contemplates a box call  10  defined by a pair of longitudinal sounding plates  11  and  13  secured at each end to a pair of end blocks  15  and  17  and along their lower edges to a generally rectangular base plate  19 . The construction and connection of the members thus described to one another may be of any conventional manner used in constructing box calls. Like wise attached to one end block  15  of the call a spring loaded striker plate  21  is mounted to selectively engage the upper edge of sounding plate  11  or  13  at the urging of the user. 
     Retained on the outside of each sounding plate  11  and  13  is a mass  23  and  24  of ferromagnetic material which may or may not be magnetized. Movably mounted within the box call is another ferromagnetic mass  27 . It will be appreciated that either mass  27  or masses  23  and  24  may be magnets or all three may be magnets. The theory of operation of the instant invention is that longitudinal sound plates  11  and  13  can be made to vary their tonal qualities by changing the tension exerted on them by the magnetic material and by changing the location of the magnets  23  and  24  using the influence of to magnet  27 . To do so the internal magnet  27  needs to be moved relative to the two side magnets such that the force between the internal magnet and each external magnet can be varied. As is known the attractive force between magnet  27  and ferromagnetic material  23  or  24  varies inversely proportionally to the distance between them. Thus if magnet  27  travels linearly along the center of the box and if ferromagnetic, masses  23  and  24  mirror each other then the magnetic tension exerted on each sounding plate will be equal. Alternatively, magnets  23  and  24  can be slidably retained on plates  11  and  13  such that they move to different locations responsive to the motion of magnet  27 , thereby changing the pressure exerted to a different point on the plates and creating a different chordal quality for the plates  11  and  13 . If the sounding plates have identical tonal qualities then the variation in tension and/or chordal quality will affect both plates to the same degree. This could be varied by spacing the magnets  23  and  24  along the length of the box such that magnet  27  moves closer to magnet  23  as it moves away from magnet  24 . Of course the sounding boards may have inherently different tonal qualities and the magnets vary the qualities of each board based on proximity of the internal and external magnetic material. 
     As may be seen in  FIGS. 1 to 3 , magnet  27  may be mounted on a spindle  31  extending along the centerline of the box call. As the magnet is moved along the spindle  31 , either manually, or by threaded connections such that the spindle may be rotated to urge the magnet long its length, the magnet moves and exerts its influence on the magnets  23  and  24  The spindle or an optional secondary drive spindle may be rotated by a thumbwheel  33  mounted for rotation in box  11  and rotating spindle  32  as shown in  FIG. 3  wherein a drive wheel  33  is mounted on spindle  32  which engages a carrier  34  connected to the magnet. Spindles  31  and  32 , drive wheel  33  and carrier  34  are preferably not ferromagnetic. 
       FIGS. 4 to 7  show a second embodiment wherein magnet  27  is mounted on the periphery of a non-ferrous disc  37  which is mounted for rotation about an axis transverse to the centerline of the box call. The disc  37  extends through the base  19  of the box call such that it can be rotated by the user to move the magnet  27 , thereby varying the pitch of the call. As may be seen in  FIG. 6  the magnets  23  and  24  are covered by protective covers  38  and  39 , which serve to hold the magnet against the sounding panels and allow for more diverse sounds by allowing the magnets  23  and  24  to be relocated along the length of the plates. 
     If the magnets  23  and  24  are held against the sounding boards magnetically, the vibration of the sound boards will have a more raspy sound than if magnets  23  and  24  are adhered directly to the board. If the magnets  23  and  24  are separated from the soundboards by a piece of felt, then the sound is more even. If a semi-rigid material such as mylar is interposed between the magnets  23 ,  24  and the sound board, the sound is raspier and more desirable for a box call. 
     It is to be understood that the forms of the invention shown are preferred embodiments thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims.