Abstract:
A ball distance measuring system incorporates a support received over a reference ball. A reference on the support has a diameter differing from a diameter of the reference ball by a predetermined amount visually distinguishable from a circumference of the reference ball presenting an even visual separation confirming concentric coincidence when centered with respect to the reference ball.

Description:
BACKGROUND INFORMATION 
       [0001]    1. Field 
         [0002]    Embodiments of the disclosure relate generally to the field of ball games and more particularly to embodiments for a measurement system incorporating a positioning device for centering over a reference ball with a measuring element attachment for distance measurement to competition balls. 
         [0003]    2. Background 
         [0004]    Games which employ a reference ball and competition balls thrown or rolled to rest as closely as possible to the reference ball are highly popular. Bocce, Petanque and lawn bowling all employ this basic premise. In many cases visually estimated measurement of the resulting spread of competition balls from the reference ball to determine the closest ball or balls may be difficult and as competition increases, the need for accurate measurement becomes very important. Of key concerns are obtaining accurate measurements without moving the reference ball during the measurements. 
         [0005]    Measuring devices such as string, telescoping rods, measuring tape, and lasers are commonly used to determine positions of competition balls relative to the reference ball in order to award points. These methods require that one end of the measuring device be placed extremely close to the horizontal edge of the reference ball without touching the ball. It is not uncommon to accidentally move the reference ball thus invalidating subsequent measurements and creating a disputable situation. 
         [0006]    Immediately after measuring a first competition ball, the measuring device must then be physically repositioned in order to measure a second competition ball. This repositioning further increases the risk of inadvertently contacting and moving the reference ball, and is time-consuming. 
         [0007]    In order to avoid the problem of accidental contact with the reference ball, and to improve time efficiency, cylinders or cups have been utilized to provide a stable support for measuring devices. These supports are carefully placed over the reference ball and provide a rotational measuring point, the vertical axis of which is centered over the reference ball. This method allows rapid comparative sequential measurements using any of the aforementioned measuring devices without repositioning the reference point on the reference ball. 
         [0008]    However, existing cylinder or cup positioning devices do not provide a means by which to accurately and precisely align the vertical measuring axis with the reference ball, and are subject to optical deficiencies and inaccuracy due to parallax errors or low visibility of the reference ball, which may create errors in measurement. 
         [0009]    It is therefore desirable to provide a highly accurate device to locate the vertical axis of the reference ball without contacting or moving the reference ball. Additionally, it is desirable that such a device accommodate various measurement elements for high accuracy of measurement from the reference ball to competition balls. 
       SUMMARY 
       [0010]    Exemplary embodiments provide a ball distance measuring system incorporating a support received over a reference ball. A reference on the support has a diameter differing from a diameter of the reference ball by a predetermined amount visually distinguishable from a circumference of the reference ball presenting an even visual separation confirming concentric coincidence when centered with respect to the reference ball. 
         [0011]    In one embodiment the support includes a cylindrical tube supporting a first reference land and a hemispherical cap extending from the cylindrical tube. The hemispherical cap has a plurality of apertures through which the first reference land may be viewed. 
         [0012]    In an alternative embodiment the support incorporates a plurality of legs and a first reference land supported by the plurality of legs. 
         [0013]    The embodiments provide a method for measuring the distance of a competition ball from a reference ball by providing a reference ball cover and supporting a first reference for visually establishing concentric coincidence with the reference ball. A measurement support is attached to the reference ball cover. A measurement device on the measurement support is employed to measure distance to a desired competition ball. 
         [0014]    The features, functions, and advantages that have been discussed can be achieved independently in various embodiments of the present invention or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a pictorial view of a first embodiment of a reference ball cover over a reference ball on a playing surface with an example competition ball; 
           [0016]      FIG. 2  is a top view of the embodiment of the reference ball cover; 
           [0017]      FIG. 3  is a side partial section view of the embodiment of the reference ball cover; 
           [0018]      FIG. 4  is pictorial view of a second embodiment of the reference ball cover; 
           [0019]      FIG. 5  is a side section view of the second embodiment of the reference ball cover with a thin wall and extending flange; 
           [0020]      FIG. 6  is a pictorial view of an alternative exemplary embodiment of the reference ball cover; 
           [0021]      FIG. 7  is a top view of the embodiment of  FIG. 6 ; 
           [0022]      FIG. 8  is a top view of the embodiment of  FIG. 6  with the equatorial reference land omitted; 
           [0023]      FIG. 9  is a top view of the embodiment of  FIG. 6  with the second reference disk removed; and, 
           [0024]      FIG. 10A  is a top view of alternative configurations of the first and second references; 
           [0025]      FIG. 10B  is a top view of a second alternative for configurations of the first and second references; 
           [0026]      FIG. 11  is a pictorial view of a distance measurement support platform installation on the embodiment of  FIG. 6 ; 
           [0027]      FIG. 12  is a side sectional view of the support platform of  FIG. 10 ; 
           [0028]      FIG. 13  is a detailed sectional view of an adjustment mechanism for the measurement edge of the support platform; 
           [0029]      FIG. 14  is a side view of a tape measure attachment on the support platform as an alternative measurement device; and, 
           [0030]      FIG. 15  is a flow chart of a method for competition ball distance measurement from a reference ball employing the embodiments disclosed herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0031]    The embodiments described herein disclose a reference ball cover with highly visible relative centering reference elements for centering the cover over the reference ball by establishing concentric coincidence between the reference elements and the reference ball. A single or double centering reference may be employed with an open architecture to facilitate maximizing light on the reference ball for accurate viewing of the reference elements. A rotational pivot is provided centered on the cover to be collinear with a vertical axis of the resting reference ball for attachment of a measuring element. An adjustable base attachable to the pivot provides an accurate placement of the measurement device for measurement from the circumferential edge of the reference ball to competition balls even with the cover in place. 
         [0032]    Referring to the drawings,  FIG. 1  shows a first embodiment of a positioning apparatus. For a playing surface  6  on which competition balls  8  are rolled or thrown, the positioning device employs a reference ball cover  10  with a cylindrical base  12  as a support for a hemispherical cap  14 . Cylindrical base  12  is formed in the exemplary embodiments from a cylindrical tube with desired thickness as will be described in greater detail subsequently. The hemispherical cap  14  incorporates windows or apertures  16  equally spaced about the circumference extending from the equator of the hemispherical cap. As seen in  FIG. 2 , the thickness of the cylindrical base  12  forms a first reference, reference land  18  for the embodiment shown, which is visible through the apertures  16 . In alternative embodiments, a thin wall may be employed in the cylindrical base and a flange extended from the wall to create the reference land. The inner diameter  20  of the cylindrical base and mating inner diameter of the cap exceed the diameter  21 , of a reference ball  22  over which the cover  10  is placed, by predetermined margin  24 . The margin is large enough to avoid contact with the reference ball during placement of the positioning device, and small enough to allow accurate visual concentric alignment. As seen in  FIG. 3 , the height  26  for the cylindrical base and equator  28  of the hemispherical cap are substantially coplanar with an equator  30  of the reference ball  22 . For the embodiment shown, the apertures  16  terminate at an upper extent at a latitude  32  on the hemispherical cap  14  which forms a reference dome  34  in the upper extent of the cap. 
         [0033]    As seen in  FIG. 2 , the reference land  18  provides a visual cue for spacing of the reference ball  22  centrally in the land making the margin  24  equidistant around the equator of the reference ball, defined herein as concentric coincidence between the reference land and the reference ball. The human eye can very accurately determine the equidistant relationship of the reference land  18  from the circumferential edge of the reference ball for accurately positioning the cylindrical base  12  concentrically with a vertical axis  23  of the reference ball. The reference land  18  when viewed from above the reference ball cover provides a distinct visual ring either of the playing surface  6  or a dark region in margin  24  about the reference ball  22  to demonstrate concentric coincidence. Viewed color present in the margin  24  (shaded in  FIG. 2  for clarity) will be dependent on whether the elements of the reference ball cover  10  are translucent allowing light to reach the playing surface  6  surrounding the reference ball or opaque providing a dark shadow in the margin. 
         [0034]    With the embodiment shown, a secondary reference is established by the dome  34  which also provides a reference for equidistant spacing on the visible sector  36  of the reference ball  22 . As with reference land  18 , dome  34  when viewed from above the reference ball cover provides a distinct visual ring of visible sector  36  of the reference ball  22  for which the human eye can accurately detect an equidistant relationship of the edge of dome  34  and circumference of the reference ball  22  as a secondary indicator of concentric coincidence. 
         [0035]    Placement of the reference land  18  coplanar with the equator of the reference preliminarily avoids parallax issues with sighting. By establishing a second complimentary equidistant spacing using the secondary reference of the dome  34  parallax error is substantially eliminated. The reference land  18  may be painted or the material of the cover chosen such that a clearly contrasting coloration is provided with the reference ball  22 , the resulting coloration perceived in margin  24  due to visible playing surface  6  on which the ball rests (or the unlit shadow presented by the margin) and the reference land  18 . The coloration of the dome  34  may be similarly contrasting with the color of the reference ball  22  to accommodate the second reference. 
         [0036]      FIGS. 4 and 5  show a second embodiment of the cover  10  with a thin wall cylindrical tube with a flange  40  providing the reference land  18 . 
         [0037]    An alternative embodiment of a reference ball cover  50  is shown in  FIG. 6 . Reference ball cover  50  employs support legs  51  in the form of a tripod  52  on which a reference land  54  is supported. The reference land  54  is supported to be coplanar with the equator  30  of reference ball  22 . As previously described with respect to the first embodiment, the human eye can very accurately determine the equidistant relationship of the reference land  54  from the reference ball  22  establishing concentric coincidence for accurately positioning the rotational pivot  64  of the tripod  52  with the vertical axis  23  of the reference ball  22  as represented in  FIG. 7  (with margin  24  shaded for reference). A secondary reference may also be established with the alternative embodiment by placement of a disk  56  at or near the upper extent of the tripod  52  which also provides a reference for equidistant spacing of the visible sector  36  of the reference ball  22  as shown in  FIG. 7 . By establishing a second equidistant spacing using the secondary reference of the disk  56  parallax error is substantially eliminated. While a tripod is shown for the embodiment, four or more legs supporting the reference land  54  and disk  56  may be employed. Additionally while the legs are shown as straight, angled legs may be employed for a closer fit around the reference ball  22 . As with the prior embodiment, the reference land  54  and disk  56  may be painted or made of materials providing contrast with the colors of the reference ball  22  and perceived color in margin  24 . In certain embodiments, the disk  56  may act as the sole reference element and the reference land  54  may be eliminated as shown in  FIG. 8 . Similarly, the disk  56  may be eliminated and the equatorial reference provided by reference land  54  solely used for positioning as shown in  FIG. 9 . 
         [0038]    While the described exemplary embodiments are continuously circular, the first reference and second reference may be segmented circular elements or points of any geometric shape positioned around the circumference of the reference ball. As shown in  FIG. 10A  for an exemplary three element display, the first reference is formed by indices  54   a  and the second reference is formed by indices  56   a . Three or more indices replacing one or both of the first or second reference provides the desired visual reference for centering of the reference ball cover over the reference ball. In a second alternative shown in  FIG. 10B , the reference indices  57   a ,  57   b  and  57   c  and  59   a ,  59   b  and  59   c  may be colored bands or clear windows on the support legs  51  of tripod  52  to create the distinction in coloration perceived by the user to center the support over the reference ball. 
         [0039]    With the reference ball cover accurately in place over the reference ball, measurement of distance to competition balls may be accomplished with several measurement devices. As show in  FIGS. 11 and 12  for the first embodiment, a support platform  60  is provided with a pin  62  to be received in a central bore  64  in the hemispherical cap  14  (as seen in  FIG. 2 ). For the embodiment shown, central bore  64  will be aligned with the vertical axis  23  of the reference ball  22 . Measurement of distance from the reference ball to the competition balls may be made from any common vertical reference and thereby provide an equivalent measurement to each competition ball. Depending on the actual measurement rules of any particular game, platform  60  may be adjustable with respect to the pin  62  for accurate placement of a reference edge  65  vertically aligned with the circumferential edge of the reference ball  22 . For example, pin  62  may be slidably retained in a slot  63  in the platform  60 , as shown in  FIG. 13 . The engagement of pin  62  in central bore  64  allows 360° rotation of the support platform for alignment of the measuring device with a competition ball at any angle relative to the reference ball. A laser range finder  66  as an exemplary measurement device may then be placed on or affixed to or integrated with the platform  60  with the laser aperture  68  aligned with the reference edge  65 . In this manner, accurate measurement pursuant to the rules from the edge of the reference ball&#39;s circumference to a competition ball may be made. Alternatively, the laser range finder may be internally adjustable (through software or other means as known in the art) to automatically compensate for aperture offset to correct the measured distance from the vertical axis  23  of the reference ball  22 . 
         [0040]    Alternatively, a measurement tape  70  may be place on or affixed to or integrated with platform  60  aligned with the reference edge  65  as shown in  FIG. 14  to perform the measurement. 
         [0041]    As shown in  FIG. 15 , measurement of distance of competition balls from a reference ball may be accomplished by providing a reference ball cover having a first reference for visually establishing concentric coincidence with the reference ball, step  1502 . The first reference may be diametrically larger than the reference ball and located coplanar with an equator of the reference ball for parallax reduction, step  1504 . A second or alternative reference diametrically smaller than the reference ball is located on the reference ball cover over the reference ball for establishing concentric coincidence with the reference ball, step  1506 . A measurement support is rotatably attached to the reference ball cover, step  1508  and a measurement edge aligned with a circumference of the reference ball, step  1510 . A measurement device on the measurement support is then employed to measure distance to a desired competition ball, step  1512 . 
         [0042]    Having now described various embodiments of the invention in detail as required by the patent statutes, those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the present invention as defined in the following claims.