Claims:
Having thus described my invention, what I
claim is
1. The combination with a bowling ball of the type having therein spaced finger openings for gripping the ball, of adjustable balancing means, comprising
2. The combination as defined in claim 1, wherein said weight is made of material similar to the material from which said bowling ball is made.
3. The combination as defined in claim 2, including a segmental spherical plug secured in the outer end of said blind bore to close said bore,
4. The combination as defined in claim 1, wherein said means for preventing the rotation of said weight comprises
5. The combination as defined in claim 4, where
6. The combination as defined in claim 5, wherein
7. The combination with a bowling ball of the type having fingerholes therein for gripping the ball, of adjustable means for balancing the ball comprising
8. The combination as claimed in claim 7, wherein said bore is of a depth and said screw is of a length to permit adjustment of said weight in said bore only within predetermined prescribed limits to limit the amount of imbalance that may be imparted to said ball by adjustment of said weight.
9. The combination as claimed in claim 8, wherein said limits are predetermined so that the maximum imbalance that may be imparted to said ball is 3 ounces.
Description:
This invention relates to bowling balls and more particularly to bowling balls of the two finger or three finger type which have to be drilled for the finger openings to suit the finger-span, finger length, etc. of the bowler.
It is customary to manufacture bowling balls of this type so that a ball is slightly denser adjacent the top of the ball, or the area into which the fingerholes are to be drilled, so that as far as feasible the ball will be in balance after the fingerholes are drilled in it. Consequently, the balls are top weighted, and slightly out of balance at the time of manufacture. Ideally, the material which is drilled from the denser ares of the ball to provide the fingerholes compensates exactly for the imbalance caused by the denser portion of the ball, so that, theoretically, after the fingerholes have been drilled, the ball is perfectly balanced. Because different bowlers require holes of different depths and differently spaced apart, the drilling of the holes, however, seldom produces a perfectly balanced ball.
Some bowlers, moreover, prefer an unbalanced ball. Expert bowlers, furthermore, like to have different amounts of imbalance in their balls depending upon the conditions of the alleys on which they are bowling. For this reason it has been the practice of expert bowlers heretofore to carry as many as eight or more bowling balls with them when then go out to bowl so that they can select from their supply of balls of differing top or bottom weights balls most suitable to the conditions of the alleys on which they are to bowl.
It is an object of this invention to provide a bowling ball, which can be perfectly balanced after the fingerholes have been drilled into the ball.
Another object of the invention is to provide a bowling ball, which will permit of adjustment of the ball to have a desired imbalance within the limits permitted by generally accepted rules of the game, so that it will no longer be a need for a bowler to carry several balls. To this end a more specific object of the invention is to provide a bowling ball balancing device, which can be mounted adjustably in a bowling ball selectively to permit accurate balancing or minor imbalancing of the ball after drilling the fingerholes in the ball.
Still another object of the invention is to provide a novel bowling ball which contains an adjustable balancing means that is made from plastic and is similar to the material from which the bowling ball itself is made.
Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompanying drawing.
In the drawing:
FIG. 1 shows a bowling ball made according to one embodiment of this invention, parts of the ball being cut away and shown in section to illustrate the balancing device which is incorporated in the ball and which permits bringing it to perfect balance, or a desired degree of imbalance within the rules, after the fingerholes have been drilled in the ball;
FIG. 2 is a fragmentary sectional view of this ball taken along the line 2-2 in FIG. 1 looking in the direction of the arrows;
FIG. 3 is an elevation of this ball on a substantially reduced scale, illustrating the disposition of the balancing device relative to the finger holes in the ball; and
FIG. 4 is a view similar to FIG. 1, but on a smaller scale, and illustrating a modified bowling ball incorporating balancing means made in accordance with a further embodiment of this invention.
Referring now to the drawing by numerals of reference, and first to FIGS. 1 to 3 inclusive, 10 denotes generally a bowling ball having therein an elongate, cylindrical blind bore 12, which extends from the outer surface of the ball radially inwardly toward, and slightly beyond, the center thereof.
Mounted in the bore 12 coaxially thereof, for example with a press fit, is an elongate plastic tube or sleeve 14 having in its inner peripheral surface a narrow, axially extending slot or keyway 16. The inner end of sleeve 14 rests on the outer, marginal portion of a flat plastic washer 18, which is seated on the flat bottom of the blind bore 12; and sleeve 14 is shorter than the bore 12 so that the outer or upper end of the sleeve is spaced axially inwardly from the outer end of bore 12. Mounted for axial reciprocation in the bore of sleeve 14 is a cylindrical, axially bored plastic block or weight 20. Secured in a recess in the outer peripheral surface of weight 20 to project slidably into a keyway 16 in sleeve 14 is a plastic key 22.
Mounted to thread into a threaded axial bore in weight 20 is an externally threaded plastic screw shaft 24, which has on its inner or lower end a reduced diameter teat 25 that extends rotatably through a hole in washer 18 into a recess or socket 26 formed in the ball 10 at the bottom of bore 12. At its outer end screw 24 has an enlarged-diameter head 27, which is connected to the threaded shank portion of the screw by a reduced-diameter neck portion 28. In its outer end head 27 has a kerf or slot 29 to accommodate the head of a conventional screwdriver. The overall length of screw 24 is slightly less than the depth of bore 12, so that the head 27 of the screw is spaced slightly axially inwardly from the outer end of bore 12.
The upper end of sleeve 14 is closed by a plastic split washer 34, which surrounds the neck portion 28 of screw 24, and the marginal, peripheral portion of which rests on the upper end of sleeve 14.
A plastic plug 36, which is made from material similar to that of the ball 10, and whose outside surface is cylindrical to conform to the outside surface of the ball, is secured by a conventional adhesive in the bore 1 2 above the head 27 of the screw. Plug 36 has an axial bore 35 that accommodates the screw head 27, when plug 36 is fastened in the ball, to permit adjustment of screw 24 by a screwdriver.
The ball illustrated is a three-finger ball with holes 37, 38 and 39 drilled therein. The invention is also applicable, however, to two finger balls. The bore 12 extends in the same general direction as the finger holes, not transversely thereto.
In the embodiment shown in FIG. 4, wherein like numerals are employed to designate elements similar to those employed in the embodiment of FIG. 1, the sleeve 14 is eliminated, and the key 22 instead projects slidably into an axially extending groove 42 formed in the wall of the blind bore 12, which is counterbored at its upper end to provide a seat for washer 34. When screw 24 is rotated the weight 20 in ball 40 reciprocates directly in bore 12 rather than in a separate sleeve.
When the ball leaves the factory it may contain the tube 14, plug 20, screw 24, and washers 18 and 34; or it may be constructed as is the ball 40 shown in FIG. 4. In the case of balls already in use, the bowler may obtain the advantages of the present invention by having his ball rebored to receive a tube 14 and have the tube 14, weight 20, screw 24 and associated parts mounted therein as shown in FIG. 1.
After the fingerholes have been drilled in a ball, screw 24 may be rotatably adjusted by a screwdriver to shift the weight 20. According to prevailing rules, a bowling ball weighing 10 pounds or over may not have more than a 3 ounce difference between the top (fingerhole section) and bottom (solid section opposite fingerhole section) halves of the ball. A bowler may, depending upon the conditions of the particular lane in which he or she is bowling, wish to bring his or her ball to perfect balance, or may wish to give the ball either a top or bottom weight, within the recognized limit of three ounces. For this reason, the bore 12 extends at its inner end slightly beyond the center of the ball.
When the weight 20 is seated in its innermost position in sleeve 14 or bore 12, it provides the ball with a one ounce imbalance in bottom weight; and when it is adjusted to its outermost position adjacent the outer end of the bore 12, the ball has a 23/4-ounce top weight imbalance. Weight 20 can thus be shifted to vary the ball imbalanced within these limits, or it can be located in an intermediate position in which perfect balance of the ball 10 is achieved.
From the foregoing it will be apparent that applicant has developed a relatively simple but extremely accurate device for balancing a bowling ball. To conform with prevailing rules the adjusting mechanism is made from plastic materials generally similar to the material from which the ball itself is made. For example, the screw 24 may be made of nylon, the weight from "Teflon," and the sleeve 14, cap 36 and washers 18 and 34 from acrylic resins. By locating this adjustment mechanism in the denser portion of the ball, it is possible to use a smaller mechanism for effecting changes in the balance of the ball, as compared to the size that would be necessary if the mechanism were to be mounted in a different, or less dense part of the ball. Also for this reason, it is not necessary to extend the bore 12 completely through the ball, but merely slightly beyond the center thereof.
The adjustable mechanism described herein will provide a single ball adjustable to suit any type or condition of alley, thus obviating the need for carrying more than a single ball to a match.
While it is desirable to place bore 12 and the associated balancing mechanism in the ball prior to drilling the fingerholes, it will be understood that the balancing mechanism may instead be inserted after the fingerholes have been drilled.