Abstract:
A marking system for use with competitively thrown objects such as discuses, shot puts, hammers and javelins. The marking system has a cavity which contains a marking agent which is automatically deposited from the cavity onto the ground when the thrown object hits the ground. Other embodiments are describes and shown.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of provisional patent application Ser. No. 61/540540 filed 1901 Jan. 01 by the present inventor. 
     
    
     FEDERALLY SPONSORED RESEARCH 
       [0002]    None 
       SEQUENCE LISTING 
       [0003]    None 
       FIELD OF THE INVENTION 
       [0004]    The present invention relates to a system and method for determining the point of impact of a object. 
       BACKGROUND OF THE INVENTION 
       [0005]    Track and field athletes participating in throwing events such as discus throw, hammer throw, javelin throw, and shot put compete by throwing objects as far as they can in a desired direction. In such a throwing event, particularly one with small variations between the performances of the competitors, there is a desire for maximal accuracy, precision, efficiency and accountability in methods of determining the point of impact of the thrown objects. 
         [0006]    Currently, at many levels of competition, the distance travelled of a thrown object is measured between a reference thrower position and a spotter marked point. The spotter marked point being determined by visual spotting by a spotter of the impact of the thrown object with the ground and placement of a marker by the spotter at the spotted point of impact. The performance of this spot and mark measurement method is limited by the ability of the spotter to accurately, precisely, efficiently, and accountably mark the point of impact while maintaining the safety of the spotter. 
         [0007]    Currently, when a throwing competitor wishes to train at its event(s), it is reliant upon a spotter to help it determine the length of its throws. Without the help of a spotter the thrower has great difficulty in efficiently evaluating the caliber of each of its throws. 
         [0008]    Efficient and reliable determination of the point of impact can be made further difficult by other aspects of the throwing event. Many throwing events are held on modern synthetic playfields on which thrown objects may leave little physical marks on the playfield surface. The location of spotter marks may be perturbed by further throws into the same space. The spotters and throwers must also be careful to ensure that the safety of the spotter is maintained during the spotting process. 
         [0009]    It will be appreciated that there is a need for improvement from the spot and mark method in throwing competitions inside and outside of the sport of track and field as well as in other systems in which a point of impact of one object with another is to be determined accurately, precisely, efficiently and accountably. 
       SUMMARY OF THE INVENTION 
       [0010]    In accordance with one embodiment a first object capable of being thrown, launched, projected or otherwise caused to impact (hereinafter thrown) a second object, has one or more cavities for storing a marking agent and a marking agent within the one or more cavities; the cavities having an orifice through which the marking agent may pass and be deposited onto the second object upon impact of the first object with the second object. 
         [0011]    One object of the present invention is to provide a system by the use of which the point of impact of a first object with a second object can be accurately, precisely, efficiently, durably, safely, and accountably marked on the second object by a marking agent born with the first object. Another object of the invention is to provide a marking agent delivery mechanism which may be implemented with various impacting objects including but not limited to discuses, shot puts, hammers and javelins. Another object of the invention is to be capable of being implemented in multiple fashions with each impacting object, including but not limited to centrally, radially, and circumferentially. Yet another object of the invention is to permit the use of varying marking agents so as to permit specific choice of marking agent to suit the marking object, to suit the object to be marked, to indicate an aspect of the thrower, and/or for aesthetic or other purposes. 
         [0012]    Accordingly several advantages of one or more aspects are as follows: to provide a means of accurately, precisely, efficiently, durably, safely and accountably marking the point of impact of the object. Other advantages of one or more aspects will be apparent from a consideration of the drawings and ensuing description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of a discus embodiment of an aspect of the invention; 
           [0014]      FIG. 2  is a partial section view of the discus of  FIG. 1  taken along line  2 - 2 ; 
           [0015]      FIG. 3  is an exploded view of the discus of  FIG. 1 ; 
           [0016]      FIG. 4  is perspective view of an alternate shot put embodiment of an aspect of the invention; 
           [0017]      FIG. 5  is perspective view of an alternate javelin embodiment of an aspect of the invention. 
           [0018]      FIG. 6  is a perspective view of a pouch/bag which may contain the marking agent for easy insertion into the thrown object  10 . 
           [0019]      FIG. 7  is a perspective view of a tool for removing the cap  14 . 
       
    
    
     REFERENCE NUMERALS 
       [0000]    
       
           10  thrown object 
           12  discus 
           14  cap 
           16  screen 
           18  marking material cavity 
           20  shot put 
           22  filler plug 
           24  javelin 
           26  filler plug 
           28  marking material 
           30  marking material pouch top 
           32  marking material pouch body 
           34  twist cap removal tool teeth 
           36  twist cap removal tool handle 
           38  pouch 
           40  cap removal tool 
           42  cap removal tool insert holes 
       
     
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    Reference is now made to the figures wherein like parts are designated with like numerals throughout. 
         [0038]    In one embodiment ( FIGS. 1-3 ) the thrown object  10  is a substantially lenticular disc or discus  12  comprising one or more cavities  18 . The cavities  18  may alternatively be circumferential or central to the object  10 . 
         [0039]    In another embodiment ( FIG. 4 ) the thrown object  10  is substantially spherical  20  comprises one or more cavities  18 . The cavities  18  may alternatively be radial or circumferential to the object. The object may alternatively comprise an attached rigid or flexible handle. 
         [0040]    In yet another embodiment ( FIG. 5 ) the thrown object  10  is an elongated shaft  24  having an end suitable for impacting a second object. The elongated shaft may comprise one or more cavities  18  within the impact suitable end. 
         [0041]    Each cavity  18  is capable of containing a marking agent  28  and is externally communicable with the periphery of the object through one or more orifices of the cavity  18 . Alternatively, each cavity  18  may be capable of accepting one or more reservoirs capable of containing the marking agent  28 . The one or more reservoirs are capable of being removably or irremovably affixed to the object  10 . The one or more reservoirs are also externally communicable with the periphery the object  10  through the orifices of the one or more cavities  18  that they occupy. 
         [0042]    Each orifice of each cavity  18  and each reservoir is capable of being removably and irremovably capped by permeable and impermeable caps  14 ,  22 , and  26 . The impermeable caps  22  and  26  are capable of preventing the marking agent  28  from leaving the cavities  18  or reservoirs through the orifices of the reservoirs or cavities  18  that they cap. The permeable caps  14  are also capable of preventing the marking agent  28  from leaving the reservoirs or cavities  18  that they cap. The permeable caps  14  are additionally capable of permitting the passing of the marking agent  28  through one or more of the reservoir and/or cavity  18  orifices, out of the object  10  and onto a second object onto which the thrown object  10  has impacted. Transmittal of the marking agent  28  through the permeable caps  14  may be by means of a screen  16 . The one or more removable caps  14 ,  22 , and  26  may have cap removal tool insert holes  42  with which the cap removal tool teeth  34  of cap removal tool  40  can engage to facilitate removal of the one or more caps by manipulation of the cap removal tool handle  36 . 
         [0043]    In another embodiment one or more caps  14  and or one or more screens  16  may be integral to the thrown object  10 . 
         [0044]    Each cavity  18  and reservoir is additionally capable of accepting a marking agent containing vessel, such as a pouch  38  ( FIG. 6 ) having a pouch top  30  and a pouch body  32 , by which marking agent may be introduced into the cavity  18  and/or reservoir. Marking agent may also be introduced into a cavity  18  or reservoir by means of a syringe. 
         [0045]    In alternative embodiments the marking agent may comprise flour, chalk, paint, calcium carbonate, calcium sulfate, Epsom salts, sand, liquid marking agents and another composition of matter suitable for marking an object when it comes into contact with the object. 
         [0046]    Although some embodiments of the present invention are illustrated as a discus  12 , a shot put  20 , and a javelin  26 , it should be known by those skilled in the art that the inventive system may be implemented on many other thrown objects, competitively thrown or otherwise. 
         [0047]    The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The above described embodiments are to be considered in all respects only as illustrative, and not restrictive and the scope of the invention.