Abstract:
An apparatus and methods for duplicating a thumb-hole of an original bowling ball into another bowling ball are disclosed. The preferred apparatus includes a bowling ball thum-bhole duplication jig for holding an original bowling ball during the casting of a flexible mold of a thumb-hole of the ball. A preferred method employs components of the jig and the flexible mold in the making of a slug for insertion into a radial slug receiving bore of another bowling ball.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a novel apparatus and methods for the duplication of a bowling ball thumb-hole from an original bowling ball into another bowling ball that simplifies the procedure from other known processes.  
           [0002]    In U.S. Pat. No. 5,813,918 issued to Conigliaro is addressed an invention entitled “Method of exactly duplicating in a new bowling ball, the thumb-hole of a reference bowling ball.” In U.S. Pat. No. 4,191,357 issued to Nesbitt, a duplicator for bowling ball finger and thumb holes is addressed. These prior devices use different apparatus and steps for the duplication of a thumb-hole from an original bowling ball into another bowling ball.  
         BRIEF SUMMARY OF THE INVENTION  
         [0003]    A principal objective of this invention is to provide a novel and improved bowling ball thumb-hole duplication jig and methods of use that have utility and allow the interior thumbcontacting topography and orientation of a thumb-hole from an original bowling ball to be duplicated into another bowling ball.  
           [0004]    A further objective is to provide an apparatus and methods that ensure compliance with the regulations governing bowling balls prescribed by the American Bowling Congress. One of the regulations establishes that the maximum diameter of a hole drilled into a bowling ball is 1 and ⅜ inches. Another American Bowling Congress regulation establishes the balance parameters that a ball with thumb-hole and finger holes must meet.  
           [0005]    The apparatus of the invention provides a novel clamping jig that securely holds an original bowling ball with an existing thumb-hole and effectively seals the end of a tube that encircles the thumb-hole to the ball without the need for sealing clay or other sealing materials before the pouring and casting of a flexible mold of the existing thumb-hole.  
           [0006]    The apparatus provides a stable tool for holding the mold during the pouring and casting of a thumb-hole slug that thereafter can be inserted into and secured in a radial slug receiving bore of a second bowling ball. A slug is a molded sleeve insert that possesses nearly the same interior thumb-contacting topography as the original thumb-hole of the original bowling ball.  
           [0007]    A further object of the invention is to provide a timesaving and useful method and apparatus for the duplication of a thumb-hole from an original bowling ball into another bowling ball.  
           [0008]    Additional and various other objects and advantages attained by the invention will become more apparent as the specification is read and the accompanying figures are reviewed. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING  
       [0009]    [0009]FIG. 1 is a schematic perspective view of a bowling ball thumb-hole duplication jig in the preferred embodiment showing an original bowling ball in place;  
         [0010]    [0010]FIG. 2 is a schematic exploded perspective view of the bowling ball thumb-hole duplication jig in the preferred embodiment showing all of its component parts without a bowling ball in place;  
         [0011]    [0011]FIG. 3 is a schematic enlarged, partial, and partially cutaway view of the jig and an original bowling ball;  
         [0012]    [0012]FIG. 4 is a sectional view of the jig and the ball along the line  4 - 4  in FIG. 3;  
         [0013]    [0013]FIG. 5 is a sectional view of the jig and the ball along the line  4 - 4  in FIG. 3 with a mold shown;  
         [0014]    [0014]FIG. 6 is a partial sectional view of the jig, the ball, and the mold along the line  6 - 6  in FIG. 3;  
         [0015]    [0015]FIG. 7 is a partial side elevational view of the mold and the ball showing a mold registration marking aligned with a y-axis of the grip of the ball;  
         [0016]    [0016]FIG. 8 is a perspective view of the mold;  
         [0017]    [0017]FIG. 9 is a sectional view of a bridge, a tube, a mold, and a slug;  
         [0018]    [0018]FIG. 10 is a perspective view of the mold and the slug;  
         [0019]    [0019]FIG. 11 is a schematic exploded perspective view of the slug aligned for insertion into a slug receiving bore of a second bowling ball; and  
         [0020]    [0020]FIG. 12 is a schematic perspective view of the slug mounted in a second bowling ball; and  
         [0021]    [0021]FIG. 13 is a partial top view of the slug mounted in the second bowling ball. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]    Referring to FIG. 1, the invention is novel and provides a bowling ball thumb-hole duplication jig  10  that beneficially assists in novel methods of duplicating a thumb-hole  20  of an original bowling ball  22  into another bowling ball. Preferably the ball  22  has markings on its surface that show a center of the grip  24 , an x-axis of the grip  26 , and a y-axis of the grip  28 . Generally, the markings are scribed lines. It is generally well known in the art that the thumbhole  20  is centered on the y-axis of the grip  28 . Preferably the scribed line showing the y-axis of the grip  28  extends along the surface of the ball  22  and intersects the original thumb-hole  20  and bisects two finger holes  30  and  32 .  
         [0023]    In the event the ball  22  does not have a marking along the y-axis of the grip  28 , then the ball may be scribed or temporarily marked with a crayon or other suitable marking device to show the y-axis of the grip  28 .  
         [0024]    The bowling ball thumb-hole duplication jig  10  comprises a jig base  40  having a vertical jig base bore  42  as shown in FIG. 2. Two bridge supports  44  are mounted to the base  40  and depend upwardly from the base. Preferably, as seen in FIG. 2, the bridge supports  44  are equally spaced from and parallel to a vertical axis of the jig base bore  42  and said supports depend vertically from the base  40 . Preferably, the supports  44  are made from stainless steel rods, but other suitable materials can be used. The supports  44  are spaced far enough apart to allow a regulation bowling ball  22  (a ball having a circumference of  27  inches) to rest supported in the jig base bore  42  and centered between the supports. Preferably, the lower ends of the supports  44  are mounted in two support mounting bores  46  through the base  40  and the supports are fixed to the base by threads on the lower ends of the supports and by cooperating nuts (threads and nuts not shown, but a technique well known to the mechanical arts). In the preferred embodiment, each upper end of the supports  44  is threaded to receive respectively a washer  48  and a wing nut  49 .  
         [0025]    The two supports  44  are attached to a clamping bridge  50 . Preferably, the clamping bridge  50  has two bridge support slots  52 , one at each end as seen in FIGS. 1 and 2. Each of the bridge support slots  52  respectively receives a bridge support  44  and cooperates with the bridge support, a washer  48 , and a wing nut  49  to secure the bridge  50  to the jig base  40 .  
         [0026]    As seen in FIGS. 3, 6, and  9 , the clamping bridge  50  has a centered lower bridge bore  54  that partially extends into the bridge  50  perpendicularly from its lower surface. The lower bridge bore  54  is coaxial with and has a larger diameter than an upper bridge bore  56  that extends fully through the bridge  50  perpendicularly from its top surface.  
         [0027]    As seen in FIG. 3, a cylindrical tube  60  having an inside diameter greater than the diameter of the original thumb-hole  20  is closely, removably, and coaxially received into and seated in the lower bridge bore  54 . Preferably, the tube  60  has a uniformly chamfered outer end  62  as seen in FIGS. 3, 6, and  9 . Preferably, the tube  60  has a longitudinal tube registration marking  64  on its outer circumference at the chamfered outer end  62  and has a fill line  66  on its inner surface near the chamfered outer end. Preferably, the tube  60  is made of PVC tubing.  
         [0028]    Preferably, the upper bridge bore  56  has the same diameter as the inside diameter of the tube  60 . Preferably, the inside diameter of the tube  60  is 1 and ⅜ inches which is the maximum allowed diameter for a hole drilled in a bowling ball under American Bowling Congress regulations.  
         [0029]    When the bowling ball thumb-hole duplication jig  10  is to be used, the jig is first placed on a level and secure work surface and then an original bowling ball  22  is placed in the jig base bore  42  on the jig base  40 . The thumb-hole  20  of the ball  22  is then centered in the jig  10  with the thumb-hole centered at the highest point of the resting ball by eye by sighting along a plane through the vertical axes of the supports  44  with the plane equally dividing the observed thumb-hole and by using a measuring tape or steel rule perpendicular to the vertical axis of the supports  44  to equally space the thumb-hole from each support. Preferably, the thumb-hole  20  is also leveled in the jig  10  by the use of a bubble level laid across the thumb-hole.  
         [0030]    Preferably, just before the jig  10  is assembled and tightened around a ball  22 , the inside of the tube  60  and the thumb-hole  20  are liberally sprayed with a suitable mold release spray.  
         [0031]    As seen in FIGS. 1, 3, and  6 , the bowling ball thumb-hole duplication jig  10  in its preferred embodiment is assembled around a ball  22  with the chamfered outer end  62  of the tube  60  evenly resting on and closely abutting the ball and encircling the thumb-hole  20 . Preferably, the jig  10  is assembled with the tube  60  aligned radial to the center of the ball  22  and the tube registration marking  64  aligned with the y-axis of the grip  28  of the ball  22 . The jig  10  is then tightened around the ball. FIG. 4 shows a portion of the y-axis of the grip  28  encircled by the tube  60 , a portion of the y-axis outside the tube, and the original thumb-hole  20 .  
         [0032]    As best seen in FIG. 1, with a ball  22  in place in the assembled bowling ball thumb-hole duplication jig  10 , the clamping bridge  50  and the tube  60  are pressured in unison down along a radius of the ball  22  and towards the jig base  40  by tightening the two wing nuts  49 . With a ball  22  in place in the jig  10 , the chamfered outer end  62  is tightened down onto the ball by tightening the two wing nuts  49  on the two bridge supports  44  whereby the chamfered outer end cooperates with the surface of the ball to temporarily seal an interface between the surface of the ball and the chamfered outer end.  
         [0033]    Preferably, after a ball  22  is centered in place, after the inside of the tube  60  and the thumb-hole  20  are liberally sprayed with a suitable mold release spray, and after the jig  10  is assembled and tightened around the ball, a flexible mold  70  is cast by pouring a mold material down through the upper bridge bore  56  to fully fill the thumb-hole  20  and partially fill the tube  60  as shown in FIG. 6. Preferably, the tube  60  is filled up to a fill line  66 . The compressed and close interface between the surface of the ball  22  and the chamfered outer end  62  prevents the leakage of any mold material out from within the tube  60 . When cured, the flexible mold  70  has a top end  72  and a bottom end  74 . FIG. 5 shows the top end  72  of the mold  70  within the tube  60 .  
         [0034]    [0034]FIG. 6 shows the preferred relationships during the casting of a mold  70  between and among the bridge  50 , the tube  60 , the chamfered outer end  62 , the ball  22 , the mold, and the thumb-hole  20 .  
         [0035]    Preferably, the mold release spray is Pol-Ease® 2300 (Polytek mold release spray) available from Polytek® Development Corp. of Easton, Pa. or some other suitable mold release spray that allows a mold  70  after curing to be removed from the thumb-hole  20  and the tube  60  without damage to the mold.  
         [0036]    Preferably, the pourable mold material used to cast the mold  70  is a two part flexible polyurethane material such as Poly 74-30 that is available from Polytek® Development Corp. of Easton, Pa. or some other suitable mold material that when cured is flexible and forms a mold that can be removed without damage from the thumb-hole  20  and the tube  60 . Other mold materials such as silicone mold rubber can also be substituted for the Poly 74-30 and used for casting a mold  70 .  
         [0037]    After the mold  70  is cured, the two wing nuts  49  are loosened and the clamping bridge  50  and the tube  60  are removed from the jig  10  and away from the ball  22  and the mold  70 . If the ball  22  has a scribed y-axis of the grip  28  that extends to the thumb-hole  20 , then the position of the scribed y-axis along a radial of the thumb-hole  20  likely is discernable on the mold  70  as a radial ridge  76  on the surface of the mold resulting from molding of mold material within the tube  60  by the scribed y-axis within the tube. The ridge  76  indexes the mold  70  to the y-axis of the grip  28 . Preferably, as shown in FIGS. 7, 8, and  10 , even if a ridge  76  is discernable, the mold  70  is indelibly marked with a mold registration mark  78  to index the mold to the y-axis of the grip  28  at the point where the y-axis meets the mold.  
         [0038]    After the mold  70  is removed from the thumb-hole  20  as shown in FIG. 8, a slug  80  can be poured and cast. Preferably, the slug  80  is cast using the bridge  50 , the tube  60 , the mold  70 , and a suitable slug casting material. As shown in FIG. 9, the mold  70  is removably mounted in the upper bridge bore  56  with its bottom end  74  extending vertically upward through the lower bridge bore  54  and into the tube  60  that is seated in the lower bridge bore.  
         [0039]    Before the casting material is poured into the tube  60 , the inside of the tube and the portion of the mold  70  open to the environment inside the tube are liberally sprayed with a suitable mold release spray such as Pol-Ease® 2300. Then a slug  80  is cast by pouring a slug casting material into the tube  60  to surround the mold  70  to a suitable depth. Preferably, as shown in FIG. 9, the tube  60  is filled to a depth to surround the mold  70  up to reach the vicinity of its bottom end  74  that in the casting process is the topmost part of the mold.  
         [0040]    A suitable material for the pouring and casting of a slug  80  is Wizard Ball Plug, a two-part urethane material, available from Ultimate Bowling Products, Inc. of Key Largo, Fla. Similar urethane materials from other sources may also be used for casting of a slug  80 . Additional materials known in the art and used for plugging holes in bowling balls may also be suitable for use in making a slug  80 .  
         [0041]    After the slug  80  has cured, the slug and the mold  70  are removed from the bridge  50  and the tube  60 . Preferably, as shown in FIG. 10, the slug  80  is indelibly marked with a slug registration mark  84  aligned with the mold registration mark  78  before the slug is separated from the mold  70  to index the slug to the mold and the mold registration mark.  
         [0042]    If the mold  70  has a radial ridge  76 , then after separation from the mold, the slug  80  may have a discernable radial groove  86  that is aligned with the slug registration mark  84 .  
         [0043]    A second bowling ball  90  is provided having a y-axis of the new grip  92  marked thereon. Preferably, the y-axis of the new grip  92  is a scribed line, but it can be a temporary marking. The alignment of the slug registration mark  84  with the mold registration mark  78  indexes the slug  80  to the y-axis of the grip  28  of the original ball  22  and allows proper indexing of the slug to the y-axis of the new grip  92  of a second bowling ball  90 . The second bowling ball  90  may also have a center of the new grip  94  and an x-axis of the new grip  96  scribed or marked thereon.  
         [0044]    As shown in FIG. 11, a radial slug receiving bore  100  with the same diameter as the inside diameter of the tube  60  is made preferably by drilling in the second bowling ball  90  radial to the center of the ball and centered on the y-axis of the new grip  92  of the second bowling ball. The slug receiving bore  100  is sized to closely receive the slug  80  and made deep enough to receive the slug flush with the surface of the ball.  
         [0045]    As shown in FIG. 11, the end of the slug  80  away from the slug registration mark  84  is inserted first into the slug receiving bore  100 .  
         [0046]    Before insertion of the slug  80  into the slug receiving bore  100 , a suitable adhesive such as Elmer&#39;s Krazy Glue or another suitable quick bonding adhesive is applied to a portion of the receiving bore to secure the slug in place within the receiving bore with the slug registration mark  84  aligned with the y-axis of the new grip  92  of the second bowling ball  90  upon full insertion of the slug into the receiving bore as shown in FIG. 12.  
         [0047]    If a radial groove  86  is discernable on the slug  80 , then upon full insertion of the slug into the receiving bore  100 , the radial groove is also aligned with the y-axis of the grip  92  as shown in FIG. 13.  
         [0048]    If a ball  22  or  90  does not have scribed x-axis and y-axis lines through the center of the grip, then such scribed lines may be replaced by temporary lines marked on the surface of the ball with a suitable marker such as a crayon, wax pencil, or grease pencil.  
         [0049]    Preferably, the jig base  40  and the clamping bridge  50  are made from white polypropylene plastic, but other suitable materials can be used.  
         [0050]    Alternatively, the two bridge supports  44  can be made of flexible cable, wire, or other suitable material. In such alternative embodiments, the preferred securing means of two washers  48  and two wing nuts  49  can be replaced with other securing means such as hooks or loops or knobs or knots or other suitable devices that secure the alternative supports to the clamping bridge  50  and allow tightening of the bridge and the tube  60  down onto the ball  22 .  
         [0051]    Alternatively, the two bridge supports  44  can be replaced with springs or elastic cords that are connected by securing means to the bridge  50  such that said springs or elastic cords pull the bridge and tube  60  down onto the ball  22 .  
         [0052]    The preceding description and exposition of the invention is presented for purposes of illustration and enabling disclosure. It is neither intended to be exhaustive nor to limit the invention to the precise forms disclosed. Modifications or variations in the invention in light of the above teachings that are obvious to one of ordinary skill in the art are considered within the scope of the invention as determined by the appended claims when interpreted to the breath to which they fairly, legitimately and equitably are entitled.