EP2797673A1

EP2797673A1 - Golf ball with co-molded core and medial layer and method of making

Info

Publication number: EP2797673A1
Application number: EP12861182.9A
Authority: EP
Inventors: Arthur P. Molinari
Original assignee: Nike Innovate CV USA
Current assignee: Nike Innovate CV USA
Priority date: 2011-12-27
Filing date: 2012-12-26
Publication date: 2014-11-05
Also published as: EP2797673A4; WO2013101807A1; JP2015505263A

Abstract

A golf ball having a core, an outer core layer, a medial layer, and a cover is disclosed, as well as a method of making. The outer core layer defines perforations therethrough. The core and medial layer are formed integrally through the perforations. A method of making a single-piece hollow shell is disclosed. A plurality of perforators is inserted into a mold and create an inner mold surface. A material is inserted into the mold to create a perforated hollow shell between the mold, the inner mold surface, and the perforated.

Description

GOLF BALL WITH CO-MOLDED CORE AND MEDIAL LAYER AND

METHOD OF MAKING

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority under 35 U.S.C. § 1 19(e) to U.S. Provisional Patent Application Number 61/580,549, entitled "Golf Ball With Co-Molded Core And Medial Layer And Method Of Making", and filed on December 27, 201 1 , which application is hereby incorporated by reference.

[0002] This application claims priority under 35 U.S.C. § 1 19(e) to U.S. Provisional Patent Application Number 61 /580,537, entitled "Method of Molding a Single-Piece Hollow Shell Including Perforations", and filed on December 27, 201 1 , which application is hereby incorporated by reference.

FIELD

[0003] The present application relates generally to a multi-layer golf ball. More specifically, the present application relates to a golf ball that includes a perforated outer core layer. A method of making the ball creates a core and a medial layer that are co-formed around the perforated outer core layer.

BACKGROUND

[0004] Golf balls are conventionally made from various types of materials. The material selected depends on the play conditions desired for the ball. In some instances, a designer may select a harder core material and in other instances the designer may select a softer core material. The core material selected affects how the ball performs and how a golfer perceives the feel of the ball.

[0005] Conventional golf balls include a series of layers. The layers are each selected to provide certain performance characteristics that, in combination, form a golf ball that has an appropriate feel for the golfer and provides an appropriate trajectory for the golfer's technique. Frequently, there is a plurality of layers that are made separately and then joined together.

Alternatively, the layers may be overmolded.

[0006] However, the use of a plurality of layers creates, by necessity, a discontinuity between the layers. This discontinuity can create a situation where the layers may cause one another to deteriorate or the multiple materials can cause cracking of the outer surface due to their different performance characteristics. In addition, the difference in the layers may create shifting of the layers relative to one another within the ball.

[0007] In addition, the core of a golf ball is traditionally fairly small in diameter. The core is often surrounded by varying types of outer core layers, medial layers, mantle layers, or the like. If it is desired to use a single material for, for example, a core layer and a medial layer, the two are often separated completely by an outer core layer or the medial layer is formed of two parts and mated with the core layer. Therefore, rather than assisting in the durability of the ball, the use of two layers of identical material instead may enhance the deterioration of the ball.

[0008] It may be desirable instead to create a ball that incorporates multiple layers that are secured to one another in order to minimize shifting between the layers. In addition, it may be desirable to use a manufacturing method that invites the use of a single material as a core material and a medial layer partially separated by an outer core layer in order to create a different performance from that available without the outer core layer.

SUMMARY

[0009] An embodiment of a golf ball includes a core, an outer core layer, a medial layer, and a cover. The outer core layer may be a hollow shell until filled with the core and may be positioned radially outward of and partially surround the core. At least one perforation may be defined through the outer core layer. The medial layer may be positioned radially outward of the outer core layer. The medial layer may be made of a material that is capable of projecting into the at least one perforation in the outer core layer. The cover may be positioned radially outward of and partially surround the medial layer. In some embodiments, the core and medial layer are formed of the same material.

[0010] In another embodiment, a method of making a golf ball is disclosed. A shell may be placed in a mold cavity. The shell may define at least one perforation therethrough. The mold cavity may be at least partially filled with a material having a viscosity and particle size capable of passing through the at least one perforation. The method may be used to mold a core within the shell and a medial layer outside the shell at substantially the same time.

[0011] In another embodiment, a golf ball includes a first stratum and a second stratum. The first stratum defines at least one perforation

therethrough. The second stratum includes three substrata. The first substratum includes a core having an outer surface. The third substratum has an outer surface and an inner surface. The second substratum includes at least one finger extending between the inner surface of the third substratum and the outer surface of the first substratum. The at least one finger extends through the at least one perforation. In some embodiments, the first stratum defines a plurality of perforations and the second substratum includes a corresponding plurality of fingers, one finger extending through each

perforation.

[0012] Various methods for making a perforated hollow sphere or shell are disclosed. A mold having a first mold surface is provided. At least one perforator is inserted into the mold. An inner mold surface creator is actuated to move an expansion area to an expanded position and to create at least a portion of an inner mold surface. A first material is inserted between the first mold surface and the inner mold surface. The first material may then be cured and the inner mold surface creator and perforator retracted. The formed perforated hollow sphere may then be ejected from the mold. If multiple perforations are desired, multiple perforators may be used.

[0013] In another embodiment, a mold having an inner surface is provided. A plurality of perforators is inserted into the mold. Each perforator has a free end sized and shaped to contact a free end of another adjacent perforator. A material is then inserted into the mold. The material may be cured and the perforators removed from the mold, at which time the single- piece hollow sphere can be removed from the mold. The free ends may be sized and shaped to interfit with one another to be capable of creating a polygonal or spherical void in the shell formed by the mold.

[0014] In another embodiment, a method of making a golf ball is disclosed. The method includes providing a mold with a first mold surface. Perforators are then inserted into the mold. The perforators cooperate to form a second mold surface spaced from the first mold surface. A first material is inserted into the mold between the first mold surface and the second mold surface. The material is cured, thereby forming a single-piece perforated hollow shell. The shell may then be inserted into a second mold and a second material is inserted into the second mold to interfit with the shell and form a golf ball inner part. The golf ball inner part may then be inserted into a third mold and covered with a golf ball cover.

[0015] Other systems, methods, features and advantages of the invention will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the invention, and be protected by the following claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.

[0017] FIG. 1 is a cross-sectional view of one embodiment of a golf ball;

[0018] FIG. 2 is a perspective view of one embodiment of an inner core layer;

[0019] FIG. 3 is a perspective view of another embodiment of an inner core layer;

[0020] FIG. 4 is a cross sectional view of an embodiment of a mold in which an embodiment of an inner core layer has been positioned;

[0021] FIG. 5 is a cross sectional view of the mold of FIG. 4 partially filled with a first material;

[0022] FIG. 6 is a cross sectional view of the mold of FIG. 4 substantially filled with the first material;

[0023] FIG. 7 is a cross sectional view of an embodiment of a second mold in which a core, inner core layer, and medial layer have been positioned, partially filled with a third material; and

[0024] FIG. 8 is an alternative embodiment of a golf ball.

[0025] FIG. 1 a is a perspective view of a simplified shell having one perforation;

[0026] FIG. 2a is a perspective view of a shell having a plurality of perforations therethrough;

[0027] FIG. 3a is a view, partially in section, of an inner mold surface creator in retracted form;

[0028] FIG. 4a is a view, partially in section, of one exemplary embodiment of an inner mold surface creator in expanded form;

[0029] FIG. 5a is a view, partially in section, of another exemplary embodiment of an inner mold surface creator in expanded form; [0030] FIG. 6a is a perspective view of a plurality of the inner mold surface creators of FIG. 5 placed adjacent one another to form an inner mold surface;

[0031] FIG. 7a is a sectional view of the structure of FIG. 6 in position within a mold;

[0032] FIG. 8a is a sectional view of a plurality of the inner mold surface creators of FIG. 4 in position within a mold;

[0033] FIG. 9 is the sectional view of FIG. 8a showing a material injection step;

[0034] FIG. 10 is the sectional view of FIG. 9 after the material has been cured and after the inner mold surface creators have been retracted;

[0035] FIG. 1 1 is a perspective view of a plurality of another embodiment of inner mold surface creators placed adjacent one another to form an inner mold surface;

[0036] FIG. 12 is a view, partially in section, of the inner mold surface creators of FIG. 1 1 in position within a mold;

[0037] FIG. 13 is an embodiment of a hollow shell that may be made using the structures shown in FIGS. 1 1 and 12;

[0038] FIG. 14 is a cross-sectional view of a second mold containing the a hollow shell being incorporated into additional layers of a golf ball; and

[0039] FIG. 15 is a cross-sectional view of a third mold containing the inner layers of the golf ball of FIG. 14 being covered by a golf ball cover.

DETAILED DESCRIPTION

[0040] The present disclosure relates to a golf ball that has a core and medial layer that are molded together or co-molded. The present disclosure also relates to a method of making such a golf ball.

[0041] Turning first to FIG. 1 , an embodiment of a golf ball 100 is shown. Golf ball 100 includes a plurality of layers. The innermost layer is core 102. Outer core layer 104 partially surrounds and is positioned radially outward of core 102. Medial layer 1 14 at least partially surrounds and is positioned radially outward of outer core layer 104. Cover 1 16 at least partially surrounds and is positioned radially outward of medial layer 1 14. Accordingly, in one aspect, golf ball 100 can be considered as including four layers. Core 102, outer core layer 104, and medial layer 1 14, including all the sub-parts, may be considered the internal layers of ball 100, and cover 1 16 may be considered the external layer.

[0042] Outer core layer 104 may be hollow and may be substantially spherical. Outer core layer 104 may include a plurality of perforations that penetrate through outer core layer 104. In the embodiment shown in FIG. 1 along the specific cross section taken, there are four perforations shown, specifically first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12. In FIG. 1 , first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12 are shown as being substantially equal in size and approximately evenly spaced around a circumference of outer core layer 104. However, such sizing and arrangement are exemplary only. Other possible embodiments and examples are shown in other FIGS, and are interchangeable with the outer core layer 104 shown in FIG. 1 . In some embodiments, outer core layer 104 may be made in a process disclosed in U.S. Patent Publication No. , currently Provisional Application

Serial No. 61/580,537, entitled "Method of Molding a Single-Piece Hollow Shell Including Perforations" [attorney docket No. 72-1 157], filed on December 27, 201 1 , the disclosure of which is incorporated by reference. In some

embodiments, the ball of this disclosure may be used in accordance with a recycling process as described in U.S. Patent Publication No. , currently Provisional Application Serial No. 61/580,525, entitled "Method of Recycling Ball and Ball for Use in Recycling Method" [attorney docket No. 72- 1 169], filed December 27, 201 1 , the disclosure of which is incorporated by reference.

[0043] Cover 1 16 is shown in the FIGS, in simplified form. In a commercial version, cover 1 16, and in particular, outer surface 1 18 of cover 1 16, is configured to be struck by a golf club. Accordingly, cover 1 16 may include various dimples, frets or lands, projections, printing, or any other features that a designer thinks would be desirable in affecting the flight path of ball 100. The particular patterns on cover 1 16 may be determined by a person having ordinary skill in the art. Cover 1 16 may be designed to be scuff resistant. Cover 1 16 may be made of any material deemed desirable for a golf ball cover, such as SURLYN or other polyurethane elastomer that has appropriate properties for a golf ball cover.

[0044] As shown in FIG. 1 , first material 101 is used to form core 102 and medial layer 1 14 and projects into and passes through first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12. First perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12 are shaped and sized in such a manner as to allow passage of first material 101 through first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12. Sizing and shaping each of first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12 in this manner allows core 102 and medial layer 1 14 to be joined to or formed integrally with one another. As shown in FIG. 1 , first material 101 fills each of first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12.

[0045] The qualities of the first material and the projections may vary depending on the full design of the ball. For example, in some embodiments, the first material may have a higher viscosity than the material shown in FIG. 1 . In some embodiments, the outer core layer may be thicker than that shown in FIG. 1 . In such an instance, it may be possible for the first material to be capable of only projecting partially through at least one of the perforations in the outer core layer from one or both of the core side or the medial layer side. In addition, in some embodiments, depending on the shape and size of the perforations and the flow characteristics of the first material, some perforations in the outer core layer may be completely filled and other perforations may be only partially filled. In some embodiments, the first material may join the core and medial layer through one or more projections, but the size of the area in which the core and medial layer are joined may be narrower or smaller in other ways than by completely filling each perforation.

[0046] The material selected to be used as the first material may be any of the typical materials used in manufacturing cores or other interior layers of a conventional golf ball. For example, the first material may be a

thermoplastic urethane or rubber, such as a polybutadiene rubber. In many embodiments, it may be useful to use a material that is solid, rather than liquid, at room temperature.

[0047] The material used to form outer core layer 104 may be similar to that used for core 102 and medial layer 1 14. However, it may be desirable to form outer core layer 104 from a second material different from first material 101 . In some embodiments, it may be desirable for first material 101 to be softer than the second material, and in other embodiments, it may be desirable for the second material to be softer than first material 101 . It may be desirable for first material 101 and the second material to differ in other respects, such as elasticity, melting temperature, and the like. Golf balls have often been made with layers having different material properties, and a person having ordinary skill in the art can select appropriate materials for the core and medial layers, outer core layer, and cover that provide a desired set of flight properties.

[0048] The embodiment of outer core layer 104 shown in FIG. 1 defines four perforations, namely, first perforation 106, second perforation 108, third perforation 1 10, and fourth perforation 1 12. First perforation 106 and third perforation 1 10 are generally aligned with one another along first axis 120. Second perforation 108 and fourth perforation 1 12 are generally aligned with one another along second axis 122. In the embodiment shown in FIG. 1 , first axis 120 and second axis 122 are generally perpendicular to one another. This number and placement of perforations is exemplary and may take other forms, as shown in FIGS. 2 and 3.

[0049] FIG. 2 shows an alternative embodiment of outer core layer 204. Outer core layer 204 is the simplest version of an outer core layer in accordance with the present disclosure. As shown in FIG. 2, outer core layer 204 is a hollow sphere until filled to form an inner core layer or center of the golf ball. Outer core layer 204 defines a single perforation 206. As will be apparent to one having ordinary skill in the art, a single perforation 206 on an outer core layer 204 has no orientation relative to other perforations or other structure.

[0050] FIG. 3 shows another alternative embodiment of outer core layer 304. Outer core layer 304 defines a plurality of perforations therethrough. Specifically, outer core layer 304 defines first exemplary perforation 306, second exemplary perforation 308, third exemplary perforation 310, fourth exemplary perforation 312, and a plurality of additional perforations. Each perforation may be aligned with another perforation or may be unaligned with any other perforation. Alternatively, some perforations may be aligned with another perforation while other perforations remain unaligned with any other perforation.

[0051] A person having ordinary skill in the art will be able to select an outer core layer that has the appropriate properties useful for a particular application. In some embodiments, it may be desirable for the core and medial layers to be joined together over as much surface area as possible. In such an instance, a person having ordinary skill in the art might select an outer core layer that defines a larger number of perforations. In other instances, it may be desirable to include a larger amount of the second material. In such an instance, a person having ordinary skill in the art might select an outer core layer that defines a smaller number of perforations or an outer core layer that has a larger thickness. In yet other instances, a person having ordinary skill in the art may wish to maximize the flow of the first material through the outer core layer in the molding process, as will be described in greater detail below. In such an instance, the selection of a perforation pattern that encourages a particular flow pattern may be desirable. Based on the characteristics desired by the person having ordinary skill in the art, the outer core layer and perforation configuration can be designed to accommodate the desired results.

[0052] Ball 100 was described above as having four layers, namely, core 102, outer core layer 104, medial layer 1 14, and cover 1 16. However, ball 100 may also be described as having three layers or strata. FIG. 8 illustrates ball 800 having the same structure as ball 100 of FIG. 1 . As shown in FIG. 8, first stratum 870 is hollow until filled to finish ball 100 and may be substantially spherical. First stratum 870 has an outer surface 872 and an inner surface 874. First stratum 870 defines a plurality of perforations passing through first stratum 870 and extending from outer surface 872 to inner surface 874. In the embodiment shown in FIG. 8, the perforations include first perforation 876, second perforation 878, third perforation 880, and fourth perforation 882. The cross-sectional shape of the perforations may be any shape that is reasonably feasible in a given molding process and that provide appropriate stability to first stratum 870. The perforations may have the same shape or different shapes. While there are four perforations shown along this cross-sectional line, first stratum 870 may have any desirable number of perforations. However, it is desirable for first stratum 870 to define at least one perforation.

[0053] Second stratum 884 has three substrata positioned in different locations relative to first stratum 870. First substratum 886 comprises and may be considered to generally be a substantially spherical solid that is desirably positioned at the center of ball 800. First substratum 886 may form the core of ball 800. Because first substratum 886 is generally solid, it includes only an outer surface 888. Outer surface 888 of first substratum 886 is adjacent inner surface 874 of first stratum 870.

[0054] Third substratum 890 comprises and many be generally considered to be substantially hollow (until filled to finish the ball) and substantially spherical. Because it is generally hollow, third substratum 890 includes inner surface 892 and outer surface 894. Inner surface 892 of third substratum 890 is positioned adjacent outer surface 872 of first stratum 870.

[0055] The second substratum of second stratum 884 comprises a plurality of fingers. These include first finger 896, second finger 898, third finger 900, and fourth finger 902. Each of first finger 896, second finger 898, third finger 900, and fourth finger 902 extends between outer surface 888 of first substratum 886 and inner surface 892 of third substratum 890. Each finger could be considered equally to extend from inner surface 892 to outer surface 888 or to extend from outer surface 888 to inner surface 892. In addition, second substratum 884 and first stratum 870 could be considered to be sandwiched between first substratum 886 and third substratum 890.

[0056] In many embodiments, it may be desirable for the number of fingers in the second substratum to correspond with the number of perforations in the first stratum. Accordingly, if the first stratum defines only a single perforation, the second substratum would desirably only include a single finger. Also, as will be discussed later in the disclosure, a molding process may be used that forms all of the second stratum integrally. In such an instance, the first substratum, the second substratum, and the third substratum are integrally formed and form a single piece. The use of such a molding process increases the likelihood that a finger will be positioned in each perforation. In addition, the use of such a molding process facilitates or encourages the material forming the second stratum to completely fill the mold cavity. Such a molding process tends to create a ball where at least one finger in the second substratum completely fills at least one perforation in the first stratum. In many cases, each finger will substantially fill a corresponding one of the perforations. The degree to which each perforation will be filled by a corresponding finger depends on many factors, including the materials selected for the first stratum and the second stratum, the temperature of the mold, various atmospheric conditions, and the like.

[0057] Covering second stratum 884 may be cover 904. Cover 904 may be substantially hollow (though filled with other layers of the ball) and substantially spherical. Accordingly, cover 904 may have inner surface 906 and outer surface 908. Cover 904 covers first stratum 870 and all three substrata of second stratum 884. Inner surface 906 of cover 904 is desirably positioned adjacent outer surface 894 of third substratum 890. Outer surface 908 of cover 904 desirably forms the outer surface of the ball to be struck by a user's club. Cover 904 may be any generally conventional cover. The properties of cover 904 may be those described in connection with cover 1 16 in FIG. 1 . Outer surface 908 of cover 904 may be configured in a manner as described earlier in connection with outer surface 1 18 of FIG. 1 . Similarly, the materials selected and limitations described in connection with outer core layer 104 may be analogously applied to first stratum 870 and the materials selected and limitations described in connection with core 102 and medial layer 1 14 may be analogously applied to second stratum 884. First stratum 870 and second stratum 884, together with all the sub-parts thereof may be considered the internal strata of ball 800 and cover 904 may be considered the external stratum of ball 800.

[0058] Those in the art will appreciate that the number of strata in any particular ball is not limited to the specific strata identified above. Other embodiments of balls may include any number of strata with fingers and corresponding perforations. It will also be appreciated that any number of fingers could be provided on any strata with corresponding perforations on any adjacent strata.

[0059] Turning now to FIGS. 4-7, a method of making a golf ball is disclosed. In FIGS. 4-7, the configuration of the outer core layer is shown as being similar to that shown in FIG. 1 . However, a person having ordinary skill in the art will be able to select another configuration of outer core layer that would be appropriate in a particular embodiment and can modify the process shown in FIGS. 4-7 to accommodate that configuration of outer core layer.

[0060] Throughout the figures, the molds, nozzles, and pins are in exemplary configurations. In some embodiments, these configurations may be altered. For example, in the figures, the seam lines of the molds are oriented to that the molds will separate by moving to the sides (in a horizontal direction), while the nozzle is positioned at the top of the mold. As will be apparent to those in the art, the molds and nozzle may be re-oriented so that the mold halves will separate by lifting one mold half away from the other or moving both halves away from each other (in a vertical direction) while the nozzle will inject from a side of the mold. The orientation of the mold halves with respect to each other and/or the nozzle and/or the pins may be shifted without undue experimentation.

[0061] As noted in FIG. 4, a golf ball can be molded using mold 430. Mold 430 may be one of a variety of types of molds, depending on the material to be molded therein. In FIGS. 4-6, first mold 430 is shown as a standard injection mold. First mold 430 may include first mold portion 432 and second mold portion 434. First mold portion 432 and second mold portion 434 can be separated from one another to place items in first mold 430 before molding occurs or to remove the formed material after molding. First mold portion 432 and second mold portion 434 form first mold cavity 436 therein. First injection port 438 may be present, for example, at the top of first mold cavity 436. First injection port 438 may be in fluid communication with first reservoir 440 that contains first material 401 . In some embodiments, first material 401 may be a highly neutralized polymer or a thermoplastic urethane. First material 401 is introduced into first mold cavity 436 from first reservoir 440 via first injection port 438.

[0062] First mold 430 may be heated or cold, depending on what material is used as the first material and what its properties are. For example, if the material used is a thermosetting material, first mold 430 may be heated so that the material is heated to its setting temperature. If, instead, the material is thermoplastic, first mold 430 may only be heated to promote the even flow of first material 401 into first mold cavity 436 to ensure that first mold cavity 436 is evenly filled. Other materials may allow first mold 430 to remain at about room temperature during molding. After first material 401 is treated in an appropriate manner to allow first material 401 to be appropriately molded, first mold 430 may be cooled or allowed to cool, if necessary. Once first mold 430 reaches room temperature and the material is allowed to cure for the appropriate amount of time, the intermediate material formed by the molding process can be removed from first mold 430. FIG. 4 shows one example of an appropriate structure for molding the intermediate structure. However, this precise structure need not be used. Instead, another structure appropriate for molding the intermediate structure could be used that is appropriate for the materials desired for the intermediate structure.

[0063] As shown in FIG. 4, first mold cavity 436 has a diameter 442 and outer core layer 404 has a diameter 444. Diameter 442 of first mold cavity 436 is larger than diameter 444 of outer core layer 404. When the diameter 444 of outer core layer 404 is smaller than the diameter 442 of first mold cavity 436, then outer core layer 404 is spaced from or positioned away from the interior wall 445 of the mold cavity 436. In order to mold an intermediate product with outer core layer 404 embedded therein, outer core layer 404 may desirably be supported within first mold cavity 436. In some embodiments, it may be desirable for the first mold cavity 436 to be spherical and have a substantially spherical interior wall 445 to correspond generally in shape to a substantially spherical and hollow outer core layer 404, so that outer core layer 404 may be considered a shell until filled.

[0064] As shown in FIG. 4, one option for properly positioning outer core layer 404 in first mold cavity 436 is to support outer core layer 404 with a plurality of pins. FIG. 4 shows the use of first pin 446, second pin 448, third pin 450, and fourth pin 452. First pin 446, second pin 448, third pin 450, and fourth pin 452 are designed to be retractable within first mold cavity 436.

[0065] FIG. 5 shows a first injection molding step. As shown in FIG. 5, first material 401 is injected via first injection port 438 between the interior wall 445 of first mold cavity 436 and outer core layer 404. While this configuration is shown in FIG. 5, alternative configurations may be possible. In some embodiments, it may be desirable to align a perforation in outer core layer 404 with first injection port 438 and to insert first injection port 438 into the cavity 454 within outer core layer 404. In other embodiments, it may be desirable to align a perforation with first injection port 438 but to keep first injection port between outer core layer 404 and interior wall 445 of first mold cavity 436. [0066] A person having ordinary skill in the art is able to modify the positioning of the outer core layer 404 within first mold cavity 436 relative to interior wall 445, first injection port 438, and any support structure, such as first pin 446, second pin 448, third pin 450, and fourth pin 452. In many

embodiments, it may be desirable to orient outer core layer 404 so that no support penetrates through a perforation. In other embodiments, it may be desired to support outer core layer 404 by inserting a support through one or more perforations. The positioning of first pin 446, second pin 448, third pin 450, and fourth pin 452 is exemplary only and may be modified to allow the appropriate support of a desired outer core layer 404.

[0067] The positioning of outer core layer 404 relative to first injection port 438 is also a consideration in the injection molding process. The material injected into mold cavity 436 from reservoir 440 through first injection port 438 may be selected to have a viscosity and particle size to make first material 401 capable of passing through at least one of the perforations through outer core layer 404. First material 401 must be injected at sufficient pressure and at an appropriate temperature to allow first material 401 to pass through at least one perforation in outer core layer 404 without deforming outer core layer 404. Accordingly, in selecting an orientation of the perforations on outer core layer 404 relative to first injection port 438, the person having ordinary skill in the art must be aware of the weight and pressure limitations of the second material from which outer core layer 404 may be made. In some embodiments, it may be possible for a solid section of outer core layer 404, such as solid section 456, to be positioned directly under first injection port 438 without deforming outer core layer 404. In some embodiments, it may be possible for a perforation to be aligned with first injection port 438 and for first material 401 injected from first injection port 438 to drop into the hollow outer core layer 404 and partially fill the interior of outer core layer 404 without deforming outer core layer 404.

[0068] As shown in FIG. 5, when first material 401 is injected into first mold cavity 436, it flows around outer core layer 404 and enters outer core layer 404 through at least one perforation therethrough. As shown in FIG. 5, first material 401 may flow over outer core layer 404 and fall by gravity or other methods to the bottom 458 of the mold cavity. While other orientations of the mold are possible, it is often desirable to use gravity to assist in the molding process, rather than needing to use additional pressure to force a molding material into a mold. When first material 401 falls to bottom 458 of first molding cavity 436, the level of first material 401 in the molding cavity rises. Eventually, as shown in FIG. 5, the level rises as high as fourth perforation 412. When first material 401 reaches this level, it is permitted to penetrate into or pass through fourth perforation 412. In many embodiments, it is desirable for first material 401 to completely fill fourth perforation 412. In other embodiments, it may be desirable for first material 401 to only partially fill fourth perforation 412.

[0069] In addition, when first material 401 is flowing over outer core layer 404, it may flow over a perforation. In some embodiments, depending on the orientation of the perforation relative to the flow of first material 401 , gravity, and the materials used, first material 401 may flow through the perforation into the hollow area 454 within the hollow, substantially spherical outer core layer 404. An example of such flow is shown in FIG. 5. In FIG. 5, first material 401 is shown as flowing through second perforation 408 into cavity 454.

[0070] As first material 401 is injected into first mold cavity 436, it fills first mold cavity 436 and outer core layer 404. As it begins to harden, it becomes capable of supporting outer core layer 404 within first mold cavity 436. As first material 401 begins to harden and support outer core layer 404, first pin 446 and fourth pin 452 can be retracted. As first material 401 begins to further fill first mold cavity 436, second pin 448 and third pin 450 can be retracted. This retraction after the partial hardening of first material 401 allows outer core layer 404 to remain centered within first mold cavity 436 and for first material 401 to evenly fill first mold cavity 436 and outer core layer 404. FIG. 5 shows a state where it may be possible to retract first pin 446 and fourth pin 452 in some embodiments.

[0071] While four pins 446, 448, 450, and 452 are shown, and while they are shown protruding only from the sides of first mold cavity 436, these features should not be seen as being limiting. In some embodiments, it may be desirable to place more or fewer pins in first mold cavity 436. In other embodiments, it may be desirable to space the pins more evenly throughout first mold cavity 436. Finally, it may be desirable to include pins on the top or bottom sides of first mold cavity 436. A person having ordinary skill in the art will be able to modify the mold design to provide an appropriate molding environment based on the materials selected and the design characteristics desired.

[0072] Turning now to FIG. 6, there is shown an embodiment of the mold where the first mold cavity 436 is substantially filled with first material 401 . In the embodiment shown in FIG. 6, the first injection port 438 has been retracted to be about even with or recessed from interior wall 445 of mold 430 in order to allow the first material to substantially fill mold cavity 436. As shown in FIG. 6, the injection step allows the filling of the interior 454 of outer core layer 404 to form core 402. The injection step also allows each perforation to be filled with first material 401 . As shown in FIG. 6, first perforation 406, second perforation 408, third perforation 410, and fourth perforation 412 are all substantially filled with first material 401 . Finally, the space between outer core layer 404 and interior mold wall 445 is filled with first material 401 to form medial layer 414. The use of such a method of molding allows the substantially simultaneous molding of a core 402 and a medial layer 414 partially separated from one another via a perforated outer core layer 404. Such a method allows the partial integration of core 402 and medial layer 414 in a single molding process and minimizes shifting between core 402 and medial layer 414 due to this integration. The degree of integration will vary depending on the materials used and the number, size, and shape of perforations in outer core layer 404.

[0073] In describing the molding process, the terms fill and filling are used. A person having ordinary skill in the art will appreciate that these terms in many embodiments do not mean to completely fill a space. In some embodiments, the use of particular materials for a mold and a material to fill the mold may, for example, cause the material to spring back from the mold, particularly upon curing. Accordingly, some small gaps that are caused by such limitations are to be expected in any manufacturing process, and these gaps do not mean that the mold is not filled.

[0074] After mold cavity 436 is substantially filled with first material 401 , first material 401 may be cured, when necessary or desirable. Various materials that are appropriate for use in the present embodiments have different curing requirements. If a thermosetting resin is used as the first material, the curing process often requires the mold to be heated after it is filled. If a thermoplastic resin is used as the first material, the curing process often requires the mold to be cooled after it is filled. Other materials might simply require the passage of time to cure. After first material 401 is cured, first mold portion 432 and second mold portion 434 are separated from one another and the intermediate product is removed from first mold 430.

[0075] FIG. 7 shows the use of second mold 530 to form a cover over the intermediate product formed in the steps shown in FIGS. 4-6. Mold 530 may be one of a variety of types of molds, depending on the material to be molded therein. In FIG. 7, second mold 530 is shown as a standard injection mold. Second mold 530 may include first mold portion 532 and second mold portion 534. First mold portion 532 and second mold portion 534 can be separated from one another to place items in first mold 530 before molding occurs or to remove the formed material after molding. First mold portion 532 and second mold portion 534 form second mold cavity 536 therein. Second injection port 538 may be present, for example, at the top of second mold cavity 536. Second injection port 538 may be in fluid communication with second reservoir 540 that contains third material 501 . In some embodiments, third material 501 may be a thermoplastic urethane, such as SURLYN®. Third material 501 is introduced into second mold cavity 536 from second reservoir 540 via second injection port 538. Although not shown in FIG. 7, the interior wall 545 of second mold cavity 536 may be patterned to mold the dimple pattern of the ball cover onto the ball cover in this step.

[0076] As shown in FIG. 7, one option for properly positioning medial layer 414 in second mold cavity 536 is to support medial layer 414 with a plurality of pins. FIG. 7 shows the use of fifth pin 546, sixth pin 548, seventh pin 550, and eighth pin 552. Fifth pin 546, sixth pin 548, seventh pin 550, and eighth pin 552 are designed to be retractable within third mold cavity 536. As third material 501 is injected into second mold cavity 536, it fills second mold cavity 536. As it begins to harden, it becomes capable of supporting medial layer 414 within second mold cavity 536. As third material 501 begins to harden, fifth pin 546 and eighth pin 552 can be retracted. As third material 501 begins to further fill second mold cavity 536, sixth pin 548 and seventh pin 550 can be retracted. This retraction after the partial hardening of third material 501 allows medial layer 414 to remain centered within second mold cavity 536 and for third material 501 to evenly fill second mold cavity 536.

[0077] While four pins 546, 548, 550, 552 are shown, and while they are shown protruding only from the sides of second mold cavity 536, these features should not be seen as being limiting. In some embodiments, it may be desirable to place more or fewer pins in second mold cavity 536. In other embodiments, it may be desirable to space the pins more evenly throughout second mold cavity 536. Finally, it may be desirable to include pins on the top or bottom sides of second mold cavity 536. A person having ordinary skill in the art will be able to modify the mold design to provide an appropriate molding environment based on the materials selected and the design characteristics desired.

[0078] Because the outer surface of medial layer 414 is substantially continuous, the placement of the pins may not need to be as complicated as in the placement of the pins in the first molding step, as the consideration of perforation placement is absent. As shown in FIG. 7, second mold cavity 536 has a diameter 542, and medial layer 414 has a diameter 544. Diameter 542 of second mold cavity 536 is larger than diameter 544 of medial layer 414. When diameter 544 of medial layer 414 is smaller than diameter 542 of second mold cavity 536, then medial layer 414 is spaced from or positioned away from interior wall 545 of second mold cavity 536. Because of the space between medial layer 414 and interior wall 545 of second mold cavity 536, third material 501 may be injected from second reservoir 540 through second injection port 538 into the space between medial layer 414 and second mold interior wall 545. This injection step is shown in FIG. 7. This step is substantially conventional, as the configuration of medial layer 414 is substantially the same on the exterior as other medial layers known in the art.

[0079] Second mold 530 may also be heated or at room temperature, depending on the material to be injected to form the cover. If second mold 530 is heated, second mold 530 may be allowed to cool. After second mold 530 reaches room temperature or after the cover, medial layer 414, and core 402 have been allowed to cure for an appropriate amount of time, the formed ball may be removed from second mold 530, such as by separating first mold portion 532 from second mold portion 534.

[0080] As noted earlier, the configuration of second mold interior wall 545 may be designed to mold the outer surface of the ball. Accordingly, the interior wall 545 may be patterned to allow for dimples and lands and other desirable markings to be molded into the cover of the ball. The precise configuration of the outer ball surface will depend on the desired ball characteristics. A person having ordinary skill in the art will be able to easily design the interior wall 545 with desired characteristics in accordance with the ball's desired characteristics without undue experimentation. The pattern of dimples on the outside of the ball may be designed independently of the characteristics for the inner layers of the ball.

[0081] The use of a structure and method as described herein may allow the present embodiments to be used in a variety of advantageous ways. First, the present embodiments may permit the greater reuse of the ball. In many conventional balls, shifting between the various ball layers is prevented or minimized by applying one or more layers of adhesive therebetween. Over time, the adhesive deteriorates due to repeated compression and expansion of the ball, as well as chemical deterioration from exposure to the adjacent ball layers. This deterioration of the adhesive then allows the layers to shift relative to one another, which may create a deterioration of the cover, through cracking or other deformity, and may create a different ball flight profile. After the deterioration has occurred, the golfer discards the ball in favor of one that has not deteriorated. If the present embodiments are used, however, no such deterioration is likely to occur. Because the layers or strata create an integral structure, no adhesive may be necessary to prevent shifting. Accordingly, since adhesive need not be used, it cannot deteriorate. The elimination of the adhesive may extend the life of the ball and allow a golfer to play the ball longer than a ball that includes adhesive.

[0082] The elimination of the adhesive also may allow for increased reuse of the ball. The layers or strata of the ball internal to the cover are typically, and also in these embodiments, made of material that has a longer life expectancy than the material used for the cover. A ball cover has increased opportunity for damage relative to internal layers, as the cover comes into contact repeatedly with a club, a tee, and the various materials present on a golf course and atmospheric elements. By further minimizing the deterioration of the internal layers by eliminating the adhesive, a golfer may choose to have a damaged cover of the ball removed and a new cover applied to the internal layers or strata to further extend the ball life. While some adhesive may be used between the cover and the layer or stratum that is immediately adjacent, such an adhesive may be easily removed mechanically or chemically before the new cover is applied.

[0083] In addition, the use of a ball with only a minimal amount of adhesive can provide for increased recyclability of the internal layers of the ball. In many instances, recycling of the first and second strata or the core, outer core layer, and medial layer of a golf ball is impeded because an adhesive is used to secure the layers together. The adhesive itself may taint the batch of material. In addition, the use of the adhesive increases greatly the difficulty of separating the materials in a recycling process, as the materials continue to stick together. The elimination of the adhesive from the internal layers or strata of the ball may allow the reuse and recycling of all the internal layers of the ball.

[0084] FIGS. 1 a and 2a show exemplary hollow spheres that may be used in connection with the present disclosure. FIG. 1 a shows a hollow sphere 100a. Hollow sphere 100a defines at least one perforation 102a therethrough. The methods disclosed herein could be used to create a hollow sphere such as hollow sphere 100a with a single perforation 102a or very few perforations around hollow sphere 100a. However, in many embodiments, it is more desirable to create a hollow sphere such as hollow sphere 200a in FIG. 2a. Hollow sphere 200a defines a plurality of perforations 202a therethrough. The number of perforations desirable in any particular further application of the shell, such as in a golf ball application, can be determined easily by a person having ordinary skill in the art. A person having ordinary skill in the art may make this determination based on the final use for the hollow shell.

[0085] In the present disclosure, the terms sphere and shell are used substantially interchangeably. In most molding situations, it is difficult to mold a precise sphere, and in many cases, there is no need to have a perfectly spherical shell for commercial use. Accordingly, the present disclosure relates to shells that may or may not be spherical. In some embodiments, it is envisioned that a shell having a non-spherical profile may be useful in some contexts. Accordingly, even if a shape is shown a substantially spherical and is described in this disclosure as being a sphere or spherical, it is understood that a substantially spherical or non-spherical shell may be equivalent in many contexts.

[0086] In order to create the perforations in the hollow shell, a perforator may be used. In general, as described in greater detail herein, the perforators of the present invention assist in the creation of the perforations in the hollow shell by acting as a movable molding surface. In other words, the perforators block the melt injected by an injection molding machine when in a first position, but are retractable to a second position to leave a void in the molded article. While in many of the embodiments described herein the perforators are injection nozzles, various embodiments of perforators are disclosed herein and a person having ordinary skill in the art can select from among the available perforators disclosed or can select an alternative perforator that is equivalent to those disclosed.

[0087] FIG. 3a shows a first embodiment of a perforator 304a.

Perforator 304a includes a hollow tube 306a. Hollow tube 306a can be inserted into or removed from a mold (not shown in this FIG.). Hollow tube 306a contains inner mold surface creator 308a. Inner mold surface creator 308a may be slidable within hollow tube 306a to move from a retracted position as shown in FIG. 3a to an active position as shown in FIGS. 4a and 5a.

Alternatively, inner mold surface creator 308a may be permanently positioned outside of free end 310a of perforator 304a and only various actuating mechanisms and links may be present within hollow tube 306a, as will be described in greater detail below. As will be better understood in conjunction with this later disclosure, if inner mold surface creator 308a is positioned permanently outside of free end 310a of perforator 304a, inner mold surface creator 308a desirably has a compressed position and an expanded position. Because inner mold surface creator 308a is positioned and removed from a mold and molded hole or perforation through the hole or perforation created by the perforator 304a, the compressed position of the inner mold surface creator 308a compresses inner mold surface creator 308a to a dimension where inner mold surface creator 308a can be removed from the mold through the perforation with perforator 304a.

[0088] Inner mold surface creator 308 can take a number of forms and can be actuated in a number of ways with varying structures. As shown in FIG. 4a, inner mold surface creator 308 includes an actuator 412a and an expansion area 414a. When it is desired that inner mold surface creator 308a form the inner mold surface, inner mold surface creator 308a, if necessary, is extended through free end 310a of perforator 304a. Inner mold surface creator 308a is desirably extended or positioned so that expansion area 414a is permitted to expand out from free end 310a of perforator 304a.

[0089] Once expansion area 414a is free from constraints from free end 310a, expansion area 414a is actuated to attain its expanded position as shown in FIG. 4a. In some instances, for example, expansion area 414a may be actuated by a spring (not shown) that automatically moves expansion area 414a from its compressed position to its expanded position when it leaves free end 310a. Alternatively, expansion area 414a could be actuated by a variety of mechanical or electrical actuators. For example, actuator 412a may be a threaded bolt and the arms of expansion area 414a move outwardly when actuator 412a is rotated one direction and move inwardly when actuator 412a is rotated the other direction. Alternatively actuator may comprise electrical wiring that actuates an electrical switch within expansion area 414a to move each arm of expansion area 414a outwardly.

[0090] The expansion area shown in FIG. 4a can be considered to be a generally umbrella or wedge shaped section. However, it is desirable for there to be material linking the outer surface of expansion area 414a with actuator mechanism 412a or free end 310a of perforator 304a. As will be discussed later, the inner mold surface creator 308a forms a mold surface. Accordingly, the surface 416a should be a resilient or solid surface that can withstand the weight or force from the material and equipment used in the molding process. Because of the desirability that expansion area 414a and hollow tube 306a mate against each other, it may be desirable in some instances for hollow tube 306a to have a curved or beveled profile 418a at free end 310a to allow hollow tube 306a to properly mate with expansion area 414a and may further include a seal or other resilient material to further enhance the mating.

[0091] An alternative embodiment of inner mold surface creator 508a is shown in FIG. 5a. FIG. 5a shows an actuator 512a in hollow tube 306a ending in expansion area 514a. Expansion area 514a may function generally like a molly bolt. When expansion area 514a clears free end 310a of hollow tube 306a, a threaded actuator 512a can be tightened to fold expansion area 514a towards hollow tube 316a. When the desired position is reached, which may be signaled by the engagement of expansion area 514a against stop 520a, expansion area 514a is pulled against free end 310a of hollow tube 316a. In order to facilitate the mating of expansion area 514a and hollow tube 306a, free end 310a may be beveled or curved as at 518a to conform in shape to expansion area 514a and may further include a seal or other resilient member to assist in the mating.

[0092] FIGS. 6a and 7a show the cooperation of a plurality of inner mold surface creators to create an inner mold surface. FIG. 6a shows the plurality of inner mold surface creators by itself for clarity and FIG. 7a shows them positioned in a mold. [0093] Throughout the figures, the molds, nozzles, and parts are in exemplary configurations. In some embodiments, these configurations may be altered. For example, in the figures, the seam lines of the molds are oriented to that the molds will separate by moving to the sides (in a horizontal direction), while the nozzle is positioned at the top of the mold. As will be apparent to those in the art, the molds and nozzle may be re-oriented so that the mold halves will separate by lifting one mold half away from the other or moving both halves away from each other (in a vertical direction) while the nozzle will inject from a side of the mold. The orientation of the mold halves with respect to each other and/or the nozzle and/or the part may be shifted without undue experimentation.

[0094] As shown in FIGS. 6a and 7a, a mold 630 is provided. Mold 630 may be one of a variety of types of molds, depending on the material to be molded therein. In FIG. 7a, first mold 630 is shown as a standard injection mold. First mold 630 may include first mold portion 632 and second mold portion 634. First mold portion 632 and second mold portion 634 can be separated from one another to place items in first mold 630 before molding occurs or to remove the formed material after molding. First mold portion 632 and second mold portion 634 form first mold cavity 636 therein. First injection port 638 may be present, for example, at the top of first mold cavity 636. First injection port 638 may be in fluid communication with first reservoir 640 that contains first material 601 . In some embodiments, first material 601 may be a natural or synthetic rubber. First material 601 may be introduced into first mold cavity 636 from first reservoir 640 via first injection port 638. First mold 630 includes first mold inner surface or wall 645. Inner surface 645 defines the outer shape of the item to be molded therein, as is typical of molds.

[0095] A plurality of perforators are inserted into mold 630. In the embodiment shown in FIGS. 6a and 7a, various perforators are partially or completely visible. These include first perforator 650, second perforator 652, third perforator 654, fourth perforator 656, fifth perforator 658, and sixth perforator 660. In the sectional view of FIG. 7a, first perforator 650, second perforator 652, fourth perforator 656, and sixth perforator 660 are not visible. Each perforator is inserted into a hole in mold 630. In the section taken in FIG. 7a, only one hole 666 is visible and shows the insertion of third perforator 654 into mold cavity 636.

[0096] Once each perforator is inserted into mold cavity 636, each inner mold surface creator is actuated to form its portion of the inner mold surface. Only some of the inner mold surfaces thus created are visible in FIGS. 6a and 7a. As shown in FIG. 6a, the inner mold surface creator for second perforator 652 has been actuated and creates second portion 662 of inner mold surface 664. Similarly, the inner mold surface creator for fourth perforator 656 has been actuated and creates fourth portion 668 of inner mold surface 662. Similarly, the inner mold surface creator for sixth perforator 660 has been actuated and creates sixth portion 670 of inner mold surface 664.

[0097] In the view shown in FIG. 7a, these inner mold surface portions are not visible. Instead, first inner mold surface portion 672, created by the action of first perforator 650 inner mold surface creator, third inner mold surface portion 674, created by third perforator 654 inner mold surface creator 676 shown in this figure, and fifth inner mold surface portion 678 created by fifth perforator 658 inner mold surface creator are visible. It is noted that as discussed earlier in the disclosure, actuation of the inner mold surface creator causes the expansion area to expand and form a portion of the inner mold surface. Also visible is a seventh inner mold surface portion 680 that is created by a perforator and actuator that are not visible in this figure.

[0098] The various inner mold surface portions need not be the same shape. In fact, in many embodiments, the inner mold surface portions will differ in shape. In FIGS. 6a and 7a, it is noted that many of the edges of the inner mold surface portions are rounded. It may be desirable in some embodiments to use rounded edges. In other embodiments, other types of edges, such as a straight edge or a beveled edge may be used. However, the plurality of perforators that are selected are typically selected and arranged in a manner so that when the corresponding expansion area for each corresponding perforator is actuated to move to its expanded position, the corresponding expansion areas form corresponding inner mold surfaces that abut one another to together form a substantially continuous inner mold surface. As shown in FIGS. 6a and 7a, it may be desirable for inner mold surface 664 to be substantially spherical.

[0099] In the embodiment shown in FIGS. 6a and 7a, an inner mold surface creator similar to that shown in FIGS. 3a and 5a is shown. If such an inner mold surface creator is used, it will tend to create a substantially hollow area 682 within inner mold surface 664.

[00100] An alternative embodiment is shown in FIG. 8a. In FIG. 8a, an inner mold surface creator similar to that shown in FIGS. 3a and 4a is shown. If such an inner mold surface creator is used, it will tend to create a filled area 882 within inner mold surface 864. The outward appearance of the perforators and inner mold surface from the outside of the mold or in non-sectional view is likely to be substantially the same whether an inner mold surface creator like that shown in FIG. 4a is used or whether one like that shown in FIG. 5a is used. The embodiment of FIG. 8a is also shown in FIG. 9 along with other equipment.

[00101] As shown in FIGS. 8a and 9, a mold 830 is provided that is a first mold that corresponds to first mold 630 described in connection with FIGS. 6a and 7a. Because they are substantially the same mold and are used in different embodiments in the same first molding step, both mold 630 and mold 830 are referred to as a first mold. Mold 830 may be one of a variety of types of molds, depending on the material to be molded therein. In FIGS. 8a and 9, first mold 830 is shown as a standard injection mold. First mold 830 may include first mold portion 832 and second mold portion 834. First mold portion 832 and second mold portion 834 can be separated from one another to place items in first mold 830 before molding occurs or to remove the formed material after molding. First mold portion 832 and second mold portion 834 form first mold cavity 836 therein. First injection port 838 may be present, for example, at the top of first mold cavity 836. First injection port 838 may be in fluid communication with first reservoir 840 that contains first material 801 . In some embodiments, first material 801 may be a natural or synthetic rubber. First material 801 may be introduced into first mold cavity 836 from first reservoir 840 via first injection port 838. First mold 830 includes first mold inner surface or wall 845. Inner surface 845 defines the outer shape of the item to be molded therein, as is typical of molds.

[00102] A plurality of perforators are inserted into mold 830. In the embodiment shown in FIGS. 8a and 9, various perforators are partially or completely visible. FIGS. 8a and 9 show first perforator 850, second perforator 852, third perforator 856, and fourth perforator 858. Each perforator is inserted into a hole in mold 830. In the section taken in FIGS. 8a and 9, only one hole 866 is visible and shows the insertion of second perforator 852 into mold cavity 836.

[00103] Once each perforator is inserted into mold cavity 836, each inner mold surface creator is actuated to form its portion of the inner mold surface. Only some of the inner mold surfaces thus created are visible in FIGS. 8a and 9. In FIGS. 8a and 9, the inner mold surface creator for first perforator 850 has been actuated and creates first portion 872 of inner mold surface 864. Similarly, the inner mold surface creator for second perforator 852 has been actuated and creates second portion 862 of inner mold surface 864. Similarly, the inner mold surface creator for third perforator 856 has been actuated and creates third portion 868 of inner mold surface 864. Finally, the inner mold surface creator for fourth perforator 858 has been actuated and creates fourth portion 878 of inner mold surface 864.

[00104] The various inner mold surface portions need not be the same shape. In fact, in many embodiments, the inner mold surface portions will of necessity differ in shape. It may be desirable in some embodiments to use rounded edges. In other embodiments, a straight edge may be used.

However, the plurality of perforators that are selected are typically selected and arranged in a manner so that when the corresponding expansion area for each corresponding perforator is actuated to move to its expanded position, the corresponding expansion areas form corresponding inner mold surfaces that abut one another to together form a substantially continuous inner mold surface. As shown in FIGS. 8a and 9, it may be desirable for inner mold surface 864 to be substantially spherical. [00105] As noted above, among the first steps in creating a single- piece hollow perforated sphere is to provide a first mold, such as first mold 630 or first mold 830. Then, a desired plurality of perforators are inserted into the first mold 630 or first mold 830. Then, an inner mold surface creator corresponding to an individual perforator is actuated to expand an expansion area associated with each individual perforator. These perforators and expansion areas are selected, arranged, designed, and positioned such that when the expansion areas are in their corresponding expanded positions, each expansion area desirably forms a portion of the inner mold surface. The expansion areas desirably abut one another and form a substantially continuous inner mold surface, such as inner mold surface 664 or inner mold surface 864. Once these steps have taken place, the steps shown in FIGS. 9 and 10 may take place. While the steps illustrated may be described in connection with the embodiment shown in FIG. 8a, the embodiment shown in FIGS. 6a and 7a or an equivalent structure could be used in the same manner to create a similar or identical result.

[00106] As noted earlier, first material 801 may be positioned in first reservoir 840. First reservoir 840 is in fluid communication with first mold cavity 836 through first injection portion 838. After inner mold surface 864 has been created and positioned in first mold cavity 836, first material 801 is inserted into mold 830 between first mold surface 845 and inner mold surface 864. First material 801 is selected from a variety of materials that are capable of being molded within mold 830 and that are capable of forming between first mold surface 845 and inner mold surface 864 and flowing and forming around the various perforators, such as exemplary perforator 852, positioned within the mold.

[00107] FIG. 9 shows an intermediate time of this step before first material 801 has completely filled the gap between first mold surface 845 and inner mold surface 864. A person having ordinary skill in the art will understand that first material 801 will continue to fill the available portion of mold 830 until it has been filled. First material 801 may then be cured or allowed to cure.

Various materials that are appropriate for use in the present embodiments have different curing requirements. If a thermosetting resin is used as the first material, the curing process often requires the mold to be heated after it is filled. If a thermoplastic resin is used as the first material, the curing process often requires the mold to be cooled after it is filled. Other materials might simply require the passage of time to cure.

[00108] After first material 801 is cured, the perforators are retracted from mold 830. As shown in FIG. 10, first perforator 850, third perforator 856, and fourth perforator 858 have been removed from mold 830. As also shown in FIG. 10, second perforator 852 is about to be removed from mold 830. Before second perforator 852 can be removed, the inner mold surface creator may be actuated again in order to cause the retraction of the expansion area into its retracted position. FIG. 10 shows expansion area 853 of second perforator 852 in its retracted position being able to be removed or retracted from mold 830 through hole 866 after actuator 855 has been actuated to cause retraction of the expanded area. Once that retraction has taken place, perforator 852, along with its component parts, including inner mold surface creator 851 , including expansion area 853 and actuator 855, can be removed from mold 830 through hole 866.

[00109] After each perforator has been removed, first mold portion 832 and second mold portion 834 may be moved away from one another to eject hollow sphere 1000 from mold 830. Hollow sphere 1000 in FIG. 10 is shown in cross-section, but in the complete mold, hollow sphere 1000 will have been formed in a single piece without any seam lines. Four perforations 1002 are shown in the portion of hollow sphere shown in FIG. 10 and may be the only substantial discontinuities in the inner surface 1004 or outer surface 1006 of single-piece hollow sphere 1000. These include first perforation 1010, second perforation 1012, third perforation 1014, and fourth perforation 1016. Each perforation 1002 was formed from the positioning of a respective perforator and inner mold surface creator in an appropriate position within mold 1000 and extends between inner surface 1004 of hollow shell 1000 and outer surface 1006 of hollow shell 1000. As shown in FIG. 10, these perforations 1002 may be spaced unevenly, and any arrangement that allows the formation of an inner mold surface could be acceptable. A person having ordinary skill in the art will be able to position the perforators to create perforations in a desired location and will be able to design, select and arrange the perforators and their associated inner mold surface creators to create an analogous hollow sphere with the desired perforation pattern.

[00110] FIGS. 14 and 15 show an exemplary embodiment of how single-piece hollow shell 1000 may be used. In the example shown in FIGS. 14 and 15, single-piece hollow shell 1000 is used in a method of making a golf ball. It is conceivable that a designer could use single-piece hollow shell 1000 in other methods to make other structures. Shell 1000 may desirably be used in any context where a single-piece hollow shell is desired for a variety of reasons. Shell 1000 may be useful in the process described in US Patent

Publication , currently Provisional Application Serial No. 61/580,549 entitled Golf Ball With Co-Molded Core and Medial Layer and Method of Making, filed on December 27, 201 1 , the disclosure of which is incorporated herein by reference.

[00111] As noted in FIG. 14, a golf ball can be molded using mold 1430. Mold 1430 may be one of a variety of types of molds, depending on the material to be molded therein. In FIG. 14, second mold 1430 is shown as a standard injection mold. Second mold 1430 may include first mold portion 1432 and second mold portion 1434. First mold portion 1432 and second mold portion 1434 can be separated from one another to place items in second mold 1430 before molding occurs or to remove the formed material after molding. First mold portion 1432 and second mold portion 1434 form second mold cavity 1436 therein. Second injection port 1438 may be present, for example, at the top of second mold cavity 1436. Second injection port 1438 may be in fluid communication with second reservoir 1440 that contains second material 1401 . In some embodiments, second material 1401 may be a highly neutralized polymer or a thermoplastic urethane. Second material 1401 is introduced into second mold cavity 1436 from second reservoir 1440 via second injection port 1438. [00112] Second mold 1430 may be heated or cold, depending on what material is used as second material 1401 and what its properties are. For example, if the material used is a thermosetting material, second mold 1430 may be heated so that the material is heated to its setting temperature. If, instead, the material is thermoplastic, second mold 1430 may only be heated to promote the even flow of second material 1401 into second mold cavity 1436 to ensure that second mold cavity 1436 is evenly filled. Other materials may allow second mold 1430 to remain at about room temperature during molding. After second material 1401 is treated in an appropriate manner to allow second material 1401 to be appropriately molded, second mold 1430 may be cooled or allowed to cool, if necessary. Once second mold 1430 reaches room temperature and the material is allowed to cure for the appropriate amount of time, the intermediate material formed by the molding process can be removed from second mold 1430. FIG. 14 shows one example of an appropriate structure for molding a golf ball inner part. However, this precise structure need not be used. Instead, another structure appropriate for molding the inner part could be used that is appropriate for the materials desired for the inner part.

[00113] FIG. 14 shows a first injection molding step. As shown in FIG. 14, second material 1401 is inserted into second mold 1430 via second injection port 1438 between the interior wall 1445 of second mold cavity 1436 and single-piece hollow shell 1000. In some embodiments, it may be desirable to align a perforation 1002 in shell 1000 with second injection port 1438 and to insert second injection port 1438 into cavity 1454 within shell 1000. In other embodiments, it may be desirable to align a perforation 1002 with second injection port 1438 but to keep second injection port 1438 between shell 1000 and interior wall 1445 of second mold cavity 1436.

[00114] When second material 1401 is injected into second mold cavity 1436, it flows around shell 1000 and enters shell 1000 through at least one perforation 1002 therethrough. Second material 1401 may flow over shell 1000 and fall by gravity or other methods to the bottom of mold cavity 1436. While other orientations of the mold are possible, it is often desirable to use gravity to assist in the molding process, rather than needing to use additional pressure to force a molding material into a mold.

[00115] In FIG. 14, second mold cavity 1436 is substantially filled with second material 1401 and second injection port 1438 has been retracted to be about even with or recessed from interior wall 1445 of mold 1430 in order to allow second material 1401 to substantially fill mold cavity 1436. The injection step allows the filling of the interior 1454 of shell 1000. The injection step also allows each perforation 1002 to be filled with second material 1401 . As shown in FIG. 14, first perforation 1010, second perforation 1012, third perforation 1014, and fourth perforation 1016 are all substantially filled with second material 1401 . The use of such a method of molding allows the substantially simultaneous molding of a core 1402 and a medial layer 1414 partially separated from one another via a perforated single-piece hollow shell 1000. Such a method allows the integration of core 1402 and medial layer 1414 in a single molding process and minimizes shifting between core 1402 and medial layer 1414 due to this integration. The degree of integration will vary depending on the materials used and the number, size, and shape of perforations 1002 in shell 1000.

[00116] The integral molding of core 1402 and medial layer 1414 around and through shell 1000 is a mechanical interfitting of shell 1000 with core 1402 and medial layer 1414. This interfitting is well within the outer circumference or surface of the golf ball inner part formed by the process of FIG. 14 and minimizes or eliminates shifting between shell 1000, core 1402, and medial layer 1414. The mechanical interfitting also minimizes or eliminates the need for a chemical attachment of core 1402, shell 1000, and medial layer 1414. This elimination of a chemical attachment improves the ability of a golf ball inner part formed in this manner to be recycled later. If first material 601 forming perforated single-piece hollow shell 1000 and second material 1401 forming core 1402 and medial layer 1414 have different properties, such as different densities, the golf ball inner part can be pulverized and first material 601 separated from second material 1401 for recycling without concern about any adhesive residue entering the recycling process. One example of a method of recycling a golf ball and a golf ball inner part made in this manner may be found in US Patent Publication No. , currently Provisional

Application Serial No. 61/580,525 entitled Method Of Recycling A Ball And Ball For Use In Recycling Method, filed on December 27, 201 1 , the disclosure of which is incorporated herein by reference.

[00117] In describing the molding process, the terms fill and filling are used. A person having ordinary skill in the art will appreciate that these terms in many embodiments do not mean to completely fill a space. In some embodiments, the use of particular materials for a mold and a material to fill the mold may, for example, cause the material to spring back from the mold, particularly upon curing. Accordingly, some small gaps that are caused by such limitations are to be expected in any manufacturing process, and these gaps do not mean that the mold is not filled.

[00118] After mold cavity 1436 is substantially filled with second material 1401 , second material 1401 may be cured, when necessary or desirable. Various materials that are appropriate for use in the present embodiments have different curing requirements. If a thermosetting resin is used as the first material, the curing process often requires the mold to be heated after it is filled. If a thermoplastic resin is used as the first material, the curing process often requires the mold to be cooled after it is filled. Other materials might simply require the passage of time to cure. After second material 1401 is cured, first mold portion 1432 and second mold portion 1434 are separated from one another and the golf ball inner part is removed from second mold 1430.

[00119] FIG. 15 shows the use of third mold 1530 to form a cover over the golf ball inner part formed in the step shown in FIG. 14. Third mold 1530 may be one of a variety of types of molds, depending on the material to be molded therein. In FIG. 15, third mold 1530 is shown as a standard injection mold. Third mold 1530 may include first mold portion 1532 and second mold portion 1534. First mold portion 1532 and second mold portion 1534 can be separated from one another to place items in third mold 1530 before molding occurs or to remove the formed material after molding. First mold portion 1532 and second mold portion 1534 form third mold cavity 1536 therein. Third injection port 1538 may be present, for example, at the top of third mold cavity 1536. Third injection port 1538 may be in fluid communication with third reservoir 1540 that contains third material 1501 . In some embodiments, third material 1501 may be a thermoplastic urethane, such as SURLYN®. Third material 1501 is introduced into third mold cavity 1536 from third reservoir 1540 via third injection port 1538. Although not shown in FIG. 15, the interior wall 1545 of third mold cavity 1536 may be patterned to mold the dimple pattern of the ball cover onto the ball cover in this step.

[00120] As shown in FIG. 15, one option for properly positioning medial layer 1414 in third mold cavity 1536 is to support medial layer 1414 with a plurality of pins. FIG. 15 shows the use of first pin 1546, second pin 1548, third pin 1550, and fourth pin 1552. First pin 1546, second pin 1548, third pin 1550, and fourth pin 1552 are designed to be retractable within third mold cavity 1536. As third material 1501 is injected into third mold cavity 1536, it fills third mold cavity 1536. As it begins to harden, it becomes capable of supporting medial layer 1414 within second mold cavity 1536. As third material 1501 begins to harden, first pin 1546 and fourth pin 1552 can be retracted. As third material 1501 begins to further fill third mold cavity 1536, second pin 1548 and third pin 1550 can be retracted. This retraction after the partial hardening of third material 1501 allows medial layer 1414 to remain centered within third mold cavity 1536 and for third material 1501 to evenly fill third mold cavity 1536. While not specifically shown and described, a similar method could be used to mold ball inner part 1414 around shell 1000.

[00121] While four pins 1546, 1548, 1550, 1552 are shown, and while they are shown protruding only from the sides of third mold cavity 1536, these features should not be seen as being limiting. In some embodiments, it may be desirable to place more or fewer pins in third mold cavity 1536. In other embodiments, it may be desirable to space the pins more evenly throughout third mold cavity 1536. Finally, it may be desirable to include pins on the top or bottom sides of third mold cavity 1536. A person having ordinary skill in the art will be able to modify the mold design to provide an appropriate molding environment based on the materials selected and the design characteristics desired.

[00122] Third mold 1530 may also be heated or at room temperature, depending on the material to be injected to form the cover. If third mold 1530 is heated, third mold 1530 may be allowed to cool. After third mold 1530 reaches room temperature or after the cover, medial layer 1414, core 1402, and shell 1000 have been allowed to cure for an appropriate amount of time, the formed ball may be removed from third mold 1530, such as by separating first mold portion 1532 from second mold portion 1534.

[00123] As noted earlier, the configuration of third mold interior wall 1545 may be designed to mold the outer surface of the ball. Accordingly, the interior wall 1545 may be patterned to allow for dimples and lands and other desirable markings to be molded into the cover of the ball. The precise configuration of the outer ball surface will depend on the desired ball characteristics. A person having ordinary skill in the art will be able to easily design the interior wall 1545 with desired characteristics in accordance with the ball's desired characteristics without undue experimentation. The pattern of dimples on the outside of the ball may be designed independently of the characteristics for the inner layers of the ball.

[00124] Alternative embodiments are possible for any of the steps shown and described above in connection with the method of making a shell and method of making a golf ball. In some embodiments, it may be desirable to make a perforated single-piece hollow shell without the use of an inner mold surface creator. The use of an inner mold surface creator that projects from a free end of a perforator allows for the creation of a perforated single-piece hollow shell that has perforations spaced from one another on both an inner and an outer surface of the shell. In other embodiments, spacing between the perforations, particularly on the inner surface, may be less important. In such an embodiment, a different method may be used to form a perforated single- piece hollow shell. An exemplary embodiment is shown in FIGS. 1 1 -13. FIGS. 1 1 and 12 show a method and structure for making such a shell and FIG. 13 shows the shell made with such a method. Because this method and structure may be substituted for that shown in FIGS. 6a and 7a or that shown in FIGS. 8a-10, and the structure made from this method can be used in the method and apparatus shown in FIGS. 14 and 15, it will be referred to as a first mold and analogous structures.

[00125] FIGS. 1 1 and 12 show the cooperation or combination of a plurality of perforators to create an inner mold surface. FIG. 1 1 shows the plurality of perforators by itself for clarity and FIG. 12 shows them positioned in a mold.

[00126] As shown in FIGS. 1 1 and 12, a mold 1 130 is provided. Mold 1 130 may be one of a variety of types of molds, depending on the material to be molded therein. In FIG. 12, first mold 1 130 is shown as a standard injection mold. First mold 1 130 may include first mold portion 1 132 and second mold portion 1 134. First mold portion 1 132 and second mold portion 1 134 can be separated from one another to place items in first mold 1 130 before molding occurs or to remove the formed material after molding. First mold portion 1 132 and second mold portion 1 134 form first mold cavity 1 136 therein. First mold 1 130 includes first mold inner surface or wall 1 145. Inner surface 1 145 defines the outer shape of the item to be molded therein, as is typical of molds.

[00127] A plurality of perforators is inserted into mold 1 130. In the embodiment shown in FIGS. 1 1 and 12, various perforators are partially or completely visible. These include first perforator 1 150, second perforator 1 152, third perforator 1 154, fourth perforator 1 156, fifth perforator 1 158, sixth perforator 1 160, seventh perforator 1 162, eighth perforator 1 164, ninth perforator 1 166, and tenth perforator 1 168. In the partial sectional view of FIG. 12, the position of these perforators is detailed. FIG. 12 is presented only in partial section to show, for example, the general appearance of a perforator exiting mold 1 130. In FIG. 12, third perforator 1 154 is shown projecting from an outer surface 1 133 of mold 1 130. Each perforator in each embodiment desirably projects from a corresponding outer surface of a corresponding mold or has an insertion and removal apparatus that is capable of causing the perforator to be inserted or removed from the mold. In some instances, an electronic insertion and removal system may be desirable. In other instances, a mechanical insertion or removal system may be desirable. In the

embodiment shown in FIG. 12, the tolerances in molding of the hollow shell may be dependent on the proper mating of the free ends of the projections. Accordingly, a supplemental system that holds the perforators in place during molding incorporated into the mold or outside the mold may be desirable in order to ensure proper placement of the perforators. These structures are not specifically shown and may be selected from any of the structures that are known to a person having ordinary skill in the art.

[00128] The manner in which the perforators create an inner mold surface may be best understood from considering the hollow shell created, as shown in FIG. 13. FIG. 13 shows a hollow shell 1300 created from the process and structure shown in FIGS. 1 1 and 12. Each perforator creates one perforation shown in FIG. 13. To create the exemplary perforation 1302, an exemplary perforator 1304 enters the mold at the first mold surface. The first mold surface corresponds generally to outer surface 1306 of perforated single- piece hollow shell 1300. While perforator 1304 would not remain in shell 1300 after it is ejected from the mold, it is illustrated here for ease of understanding.

[00129] Perforator 1304 includes free end 1308. Free end 1308 is tapered. Each perforator 1304 is inserted into the mold to create a

corresponding perforation 1302 in shell 1300. Each perforator 1304 and free end 1308 cooperates with the other perforators 1304 and free ends 1308 to form a solid shape where they meet. This area is shown as 1 170 in FIG. 1 1 and forms void 1310 in the middle of shell 1300. These free ends 1308 are shaped and sized to contact the free end 1308 of at least one adjacent perforator 1304. As shown in FIG. 1 1 , the free end of third perforator 1 154 contacts at least the free end of second perforator 1 152 and may contact the free ends of some or all of the other perforators. If all the perforators taper to meet at a single point in the center of mold 1 130, all the perforators may contact all the other perforators. In other embodiments, some or all of the perforators may contact fewer than all the other perforators. This contact between the perforators effectively creates a solid surface in the center of mold 1 130 and effectively creates an inner mold surface through the combined or cooperative action of the free ends of the perforators.

[00130] In some embodiments, it may be desirable to simplify the interfitting of the perforators. For example, it may be desirable in one embodiment for void 1310 to resemble a soccer ball. A soccer ball typically combines thirty-two panels to form a truncated isocahedron formed from twelve regular pentagon shapes and twenty regular hexagon shapes. A designer could create twenty perforators having a hexagonal cross section that have free ends that each taper to a point and twelve perforators having a pentagonal cross section that also have free ends that taper to a point. The taper of the free ends may be selected so that the free ends of the thirty two perforators meet at a central point and they interfit with one another to form a soccer ball shaped void in the center of the hollow shell. This selection of a shape may be well known and may be relatively easy for a person having ordinary skill in the art. If a greater or lesser number of perforators is desired, a designer can select an appropriate cross section of perforator to be used to create an appropriate central void. As noted, the central void 310 may be polygonal or spherical, depending on the desires of the designer, constraints of the materials used, and the like. The designer can select an appropriate taper for the free ends to create the desired shape, whether spherical or polygonal. FIG. 12 shows, for example that first perforator 1 150 might be octagonal in cross section and second perforator 1 152 might be square in cross section, and that the two different shapes may be used together in the same molding process.

[00131] FIGS. 1 1 -13 do not show some of the structures shown in the earlier analogous FIGS., and other structures not shown in the analogous FIGS, are shown. It will be apparent to one of ordinary skill in the art that the structures shown in the earlier FIGS, may be used in this FIG. and the modifications shown in this FIG. can be applied to the structures in the previously disclosed embodiments.

[00132] For example, FIGS. 1 1 and 12 do not include the specific structures shown in earlier FIGS, to insert a material into a mold. These structures were eliminated from these FIGS, to provide greater clarity and show different features that were not shown in the earlier FIGS. However, in the structure and method shown in FIGS. 1 1 and 12, it is apparent that a material is inserted into first mold cavity 1 136. The material is cured in an appropriate manner, as described in greater detail in connection with FIGS. 6a, 7a, 8a, 9, and 10 above. After the material is cured, the perforators are removed from mold 1 130 and first mold portion 1 132 and second mold portion 1 134 may be separated from one another to eject perforated single-piece hollow shell 1300 as shown in FIG. 13.

[00133] While various embodiments of the invention have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more

embodiments and implementations are possible that are within the scope of the invention. Further, any feature of any embodiment herein may be used in any other embodiments described here, either as a substitute for another feature or in addition to the features of the other embodiments, unless specifically limited herein. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.

Claims

WHAT IS CLAIMED IS:

1 . A golf ball, comprising:

a core;

an outer core layer positioned radially outward of and partially surrounding the core and defining at least one perforation therethrough, wherein the outer core layer is a shell substantially filled with the core;

a medial layer positioned radially outward of and surrounding the outer core layer, the medial layer being formed of a material capable of projecting into the at least one perforation in the outer core layer; and

a cover positioned radially outward of and surrounding the medial layer.

2. The golf ball according to claim 1 , wherein the core and the medial layer are formed of the same material.

3. The golf ball according to claim 1 , wherein the outer core layer is substantially spherical.

4. The golf ball according to claim 1 , wherein the material of the medial layer projects through the at least one perforation and is joined with the core.

5. The golf ball according to claim 1 , wherein the at least one perforation is filled with material joining the medial layer and the core.

6. A method of making a golf ball, comprising:

positioning a shell in a mold cavity, the hollow shell defining at least one perforation therethrough; and

at least partially filling the mold cavity with a material, the material having a viscosity and particle size capable of passing through the at least one perforation so that the material substantially fills the hollow shell.

7. The method of making a golf ball according to claim 6, wherein the mold cavity has a diameter and the outer core layer has a diameter smaller than the mold cavity diameter, the method further comprising positioning the shell in the mold cavity away from an interior wall of the mold cavity.

8. The method of making a golf ball according to claim 6, wherein the step of at least partially filling the mold cavity with a material comprises injecting the material into the mold cavity between the mold cavity interior wall and the shell.

9. The method of making a golf ball according to claim 8, wherein the injecting step further comprises injecting the material at sufficient pressure to allow the material to pass through the at least one perforation in the shell without deforming the shell.

10. The method of making a golf ball according to claim 9, wherein the injecting step further comprises substantially filling the shell with the material.

1 1 . The method of making the golf ball according to claim 10, wherein the injecting step further comprises substantially filling the mold cavity with the material.

12. The method of making a golf ball according to claim 1 1 , further comprising allowing the material to substantially fill each perforation in the outer core layer.

13. The method of making a golf ball according to claim 12, further comprising covering the material with a cover.

14. The method of making a golf ball according to claim 9, wherein the material forms a center of the golf ball.

15. The method of making a golf ball according to claim 6, wherein the mold cavity has a substantially spherical interior wall and the outer core layer is substantially spherical.

16. The method of making a golf ball according to claim 6, further comprising filling the mold cavity with the material.

17. The method of making a golf ball according to claim 16, wherein the step of filling the mold cavity comprises allowing the material to pass through at least one perforation in the shell.

18. The method of making a golf ball according to claim 17 further comprising filling the shell with the material.

19. The method of making a golf ball according to claim 18, further comprising filling each perforation in the outer core layer with the material.

20. The method of making a golf ball according to claim 19, further comprising extruding the material through at least one perforation so that the outer core layer becomes surrounded by the material.

21 . The method of making a golf ball according to claim 20, further comprising covering the material with a cover.

22. A golf ball, comprising:

a first stratum defining at least one perforation therethrough; and a second stratum positioned adjacent to the first stratum, wherein the second stratum includes at least one finger that extends through the at least one perforation defined by the first stratum.

23. The golf ball according to claim 22, wherein the second stratum includes three substrata, the three substrata comprising

a first substratum comprising a core having an outer surface; a third substratum having an outer surface and an inner surface; and a second substratum comprising the at least one finger, wherein the at least one finger extends between the inner surface of the third substratum and the outer surface of the first substratum.

24. The golf ball according to claim 22, wherein the first stratum defines a plurality of perforations.

25. The golf ball according to claim 24, wherein the second substratum comprises a plurality of fingers extending from the outer surface of the first substratum to the inner surface of the third substratum, each of the plurality of fingers extending through one of the plurality of perforations.

26. The golf ball according to claim 23, wherein the first substratum, the second substratum, and the third substratum are integrally formed.

27. The golf ball according to claim 23, further comprising a cover covering the third substratum.

28. The golf ball according to claim 23, wherein the at least one finger of the second substratum substantially fills the at least one perforation in the first stratum.

29. A method of making a single-piece hollow shell, comprising:

providing a mold having a first mold surface;

inserting at least one perforator into a mold;

actuating an inner mold surface creator to move an expansion area to an expanded position and to create at least a portion of an inner mold surface; and inserting a first material between the first mold surface and the inner mold surface.

30. The method of making a single-piece hollow shell according to claim 29, further comprising curing the first material.

31 . The method of making a single-piece hollow shell according to clam 29, further comprising actuating the inner mold surface creator to cause the retraction of an expanded area.

32. The method of making a single-piece hollow shell according to claim 29, further comprising removing the at least one perforator from the mold.

33. The method of making a single-piece hollow shell according to claim 29, further comprising ejecting a formed shell from the mold.

34. The method of making a single-piece hollow shell according to claim 29, further comprising inserting a plurality of perforators into the mold.

35. The method of making a single-piece hollow shell according to claim 34, further comprising actuating a corresponding plurality of inner mold surface creators to cause corresponding expansion areas to move to their

corresponding expanded positions.

36. The method of making a single-piece hollow shell according to claim 35, further comprising selecting and orienting each of the plurality of inner mold surface creators so that the inner mold surface creators together create a substantially continuous inner mold surface.

37. The method of making a single-piece hollow shell according to claim 35, further comprising selecting and orienting each of the plurality of inner mold surface creators so that the inner mold surface creators together create a substantially continuous spherical inner mold surface

38. A method of making a single-piece hollow shell, comprising:

providing a mold having an inner surface;

inserting a plurality of perforators into a mold, each perforator having a free end being shaped and sized to contact a free end of at least one adjacent perforator; and inserting a material into the mold.

39. The method of making a single-piece hollow shell according to claim 38, further comprising tapering the free end of at least one perforator.

40. The method of making a single-piece hollow shell according to claim 38, further comprising configuring the free ends of the perforators to interfit with one another.

41 . The method of making a single-piece hollow shell according to claim 38, further comprising curing the material.

42. The method of making a single-piece hollow shell according to claim 41 , further comprising removing the perforators.

43. The method of making a single-piece hollow shell according to claim 42, further comprising configuring the free ends of the perforators to interfit with one another to be capable of forming a substantially spherical void within the material being molded.

44. The method of making a single-piece hollow shell according to claim 42, further comprising configuring the free ends of the perforators to interfit with one another to be capable of forming a polygonal void within the material being molded.

45. A method of making a golf ball, comprising:

providing a first mold having a first mold surface;

inserting a movable molding surface into the first mold, the movable molding surface cooperating to create a second mold surface spaced from the first mold surface;

inserting a first material into the first mold between the first mold surface and the second mold surface; curing the first material to form a single-piece perforated hollow shell; inserting the shell into a second mold; and

inserting a second material into the second mold to interfit with the shell and form a golf ball inner part.

46. The method of making a golf ball according to claim 45, further comprising inserting the golf ball inner part into a third mold to cover the golf ball inner part with a cover.

47. The method of making a golf ball according to claim 45, further comprising tapering a free end of each movable molding surface.

48. The method of making a golf ball according to claim 45, further comprising actuating an inner mold surface creator on each movable molding surface to create the second mold surface.