BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to a golf ball that can be used to practice putting, and the golf ball of this invention emphasizes how to properly strike the golf ball with a putting stroke. Discussion of Related Art hi order to develop an enhanced, accurate and precise putting skill, people can practice with different known practice instruments on actual or simulated putting greens or other similar surfaces. For enhancing putting skills, it is important to practice properly striking the golf ball, with a complete follow-through motion. In a manner which is similar to sweeping with a broom, one proper manner for putting is to use a similar sweeping motion with the putter on the golf ball, and to not simply hit the golf ball, particularly to putt or move the golf ball a certain distance and at a desired angle. For beginning golfers, this putting technique is relatively difficult to master. hi some known designs or devices for practicing putting of a golf ball, rather than the ball being flicked or propelled outward, the ball is moved at a slower speed and thus allows the user to see a direction or angle that the ball follows when putted. One problem with this known design is that the putting golf ball uses a different material than regular golf balls and thus makes it difficult for the user to transition from practice golf balls to regular golf balls. There is an apparent need for a golf ball that can be used to practice putting strokes, particularly where there is no need to overcome a transition from using a practice golf ball to using a regular golf ball.

SUMMARY OF THE INVENTION

It is one object of this invention to provide a practice golf ball that has similar material and composition characteristics to a regular golf ball, so that the user achieves immediate response to proper form of putting strokes, when using a practice golf ball and a regular golf ball.

The above and other objects of this invention are accomplished with a golf ball that is designed and can be used as a practice putting ball, for example to practice golf putting strokes. The golf ball of this invention has a cover, such as made of an outer shell and/or an

inner shell, similar to covers of conventional golf balls, that forms a void, a cavity or a core.

In one embodiment of this invention, the core is filled 40% to 60% with a liquid, so that when putting the practice golf ball, a proper putting stroke, hit and/or follow-through motion must be followed in order to properly putt the ball. When properly putt, for example, the ball moves in a relatively normal direction and/or manner. With a ball having a core according to this invention, if the proper putting form is not followed, then the ball will waver or wobble back and forth, such as from side to side, rather than follow through in a forward motion, because of the partially filled fluidic or liquidic core.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a partial sectional perspective view of an outer shell, an inner shell and a core of a golf ball, according to one embodiment of this invention;

Fig. 2 shows a partial sectional perspective view of a golf ball having an outer shell, an inner shell, a core and an object within the core, according to another embodiment of this invention; and Fig. 3 shows a partial sectional perspective view of a golf ball having an outer shell, an inner shell, a core and an object within the core, according to another embodiment of this invention.

DESCRIPTION OF PREFERRED EMBODIMENTS Fig. 1 shows a perspective view with a cutaway portion revealing a partial sectional view, of golf ball 10 according to one embodiment of this invention. Fig. 2 shows a similar view of golf ball 10, but with object 60 positioned within core 40, according to another embodiment of this invention.

As used throughout this specification and in the claims, the phrase golf ball is intended to relate to the type of ball that is used to practice or play the sport of golf or any other similar sport. It is apparent that golf ball 10 can also be used with any other sport or for any other practice or non-practice purpose. Also as used throughout this specification and in the claims, the term object is intended to relate to any suitable object that can be positioned within core 40. For example, object 60 may comprise a spherical element, such as a ball bearing or other similar spherical structure. As shown in Figs. 1 and 2, golf ball 10 comprises inner shell 30 forming void, cavity or core 40 that is empty or hollow. Outer shell 20 surrounds inner shell 30. Outer shell

20 and/or inner shell 30 can have any suitable structure, including one layer or more layers, and

can be made from any suitable material known to those skilled in the art of golf ball design and manufacture.

In one embodiment of this invention, core 40 is filled 40% to 60% with a fluid, hi one embodiment of this invention, fluid 50 occupies 40% to 60% of a volume of core 40. For example, a volume of fluid 50 can be 40% to 60% of the volume of core 40. hi the embodiment shown in Fig. 2, object 60 is positioned within core 40. As shown in Fig. 2, object 60 is positioned within fluid 50. hi one embodiment of this invention, the combined volume of fluid 50 and the one or more objects 60 have a combined volume that is 40% to 60% of the volume of core 40. hi one embodiment of this invention, one spherical object, such as a ball bearing, is added to fluid 50 to balance the weight of golf ball 10, for example, so that the weight of golf ball 10 is the same whether it is used for practice purposes according to this invention or for regular play. Differently sized and/or weighted objects 60 can be used to accomplish a practice golf ball 10 of this invention that has the same weight as a regular golf ball, such as 45 grams, or more or less.

Fig. 3 shows another embodiment of object 60 positioned within core 40. As shown in Fig. 3, object 60 comprises a spherical element positioned within core 40. As shown in Fig. 3, the spherical element or ball-type structure has core 70 which can be at least partially filled with a fluid, such as a liquid, hi the embodiment shown in Fig. 3, core 40 can be partially filled with fluid 50 or completely filled with fluid 50, so that object 60 is completely submersed or immersed within fluid 50. The amount of fluid within the spherical element of object 60 can be any suitable percentage, including 40% to 60% of the volume of core 70. hi this particular embodiment, fluid 50 may include an oil or another suitable lubricant based fluid that allows object 60 to rotate with relative ease, with respect to outer shell 20 and/or inner shell 30. Although shown as a spherical element in Fig. 3, it is apparent that object 60 can have any other suitable shape.

Outer shell 20 can be similar in size, shape and/or material to a regular conventional golf ball. Outer shell 20 may comprise a plurality of dimples, as shown in Figs. 1 and 2 on the outer surface of outer shell 20. For example, each dimple can have a diameter between 3 and 5 mm, and may also include about 300 to about 500 total dimples. The number of dimples and the particular design of the dimples affects the aerodynamics and thus the spin of golf ball 10, and can create lift forces from air flowing over outer shell 20 when the ball is

in flight. Dimples can be used to increase the distance the golf ball can travel when hit, for example up to an increase of 30% in distance.

Golf ball 10 according to this invention differs from other regular conventional golf balls, for one reason because of empty or hollow core 40, and the particular design of core 40. Because practice golf ball 10 of this invention can be used specifically for putting practice rather than long-distance drives, a less durable material can be used for outer shell 20 and/or inner shell 30.

Empty or hollow core 40 of golf ball 10, according to this invention, can be at least partially filled with any suitable fluid 50, such as a liquid, and is preferably filled between 40% to 60% with fluid 50. Fluid 50 may comprise any suitable material, such as water, alone or in combination with any other suitable fluid. The content of fluid 50, such as a liquid within core 40, can be within the 40% to 60% range, so that the mobility of fluid 50 is not compromised.

When golf ball 10 of this invention is properly and/or correctly hit and a proper follow-through motion is performed, fluid 50 within core 40 will not cause the golf ball to move abnormally in any direction and/or manner. Thus, when the user hits golf ball 10 of this invention, the reactive motion will be similar to the reactive motion of a properly hit regular conventional golf ball. However, when the proper putting form is not followed, then fluid 50 within core 40 will swirl around and impede the forward momentum of golf ball 10, thereby disrupting a motion, angle and/or direction that golf ball 10 travels when hit. When not properly hit, it will become immediately apparent to the user that his or her putting form needs to be corrected.

In one embodiment according to this invention, a method for manufacturing golf ball 10 includes surrounding inner shell 30 with outer shell 20 and forming core 40 with inner shell 30. Fluid 50 can be positioned within core 40, preferably in a volumetric amount of 40% to 60% of the total volume of core 40. In one embodiment, object 60 can be added within core 40.

Because the resulting golf ball 10 according to this invention will have the same or similar weight to a regular or conventional practice golf ball, the user can experience an immediate, automatic correction to enhance and/or improve a putting form or a putting stroke.

This invention is described with reference to the particular illustrative embodiments, and this invention is not to be restricted by the described embodiments. It is to

be appreciated that those skilled in the art can change or modify the embodiments described in this specification and in the claims without departing from the scope and spirit of this invention.