Golf-ball-cover casting molds with self-centering mold-cavity inserts

• US 20090166924A1
• Filed: 12/26/2007
• Published: 07/02/2009
• Est. Priority Date: 12/26/2007
• Status: Active Grant

• Current Assignee: Taylor Made Golf Co., Inc.
• Original Assignee: Taylor Made Golf Co., Inc.
• Inventors: Kuttappa, Sanjay Mukatira
• Granted Patent: US 8,021,590 B2
• Time in Patent Office: Days
• US Class Current: 264/277
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/0075 Three piece balls, i.e. cover, intermediate layer and core
• CPC Class Codes: A63B 37/0087 Deflection or compression
• CPC Class Codes: A63B 45/00 Apparatus or methods for manufacturing balls working of plastics or substances in a plastic state B29
• CPC Class Codes: B29C 2043/3665 cores or inserts, e.g. pins, mandrels, sliders
• CPC Class Codes: B29C 33/0022 Multi-cavity moulds B29C33/301 takes precedence
• CPC Class Codes: B29C 33/30 Mounting, exchanging or centering moulds, mould parts or cores; B29C33/485 takes precedence
• CPC Class Codes: B29C 33/303 centering mould parts or halves, e.g. during mounting
• CPC Class Codes: B29C 33/306 Exchangeable mould parts, e.g. cassette moulds, mould inserts moulds with exchangeable mould parts for injection moulding B29C45/2673; mounting of exchangeable mould inserts for injection moulding B29C45/2675
• CPC Class Codes: B29C 39/10 incorporating preformed parts or layers, e.g. casting around inserts or for coating articles coating a surface by casting in general B05D1/30, B29C39/126 takes precedence
• CPC Class Codes: B29C 43/027 having an axis of symmetry B29C43/102 takes precedence
• CPC Class Codes: B29C 43/36 Moulds for making articles of definite length, i.e. discrete articles
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: B29L 2031/54 Balls
• CPC Class Codes: B29L 2031/545 Football balls

Abstract

Molds are disclosed for forming golf-ball covers by casting. An exemplary mold includes first and second support members that are placeable in face-to-face opposition to each other. At least one respective mold-cavity insert, defining a respective hemispherical cavity, is mounted to each support member. The mold-cavity insert is floatable in at least three (e.g., x, y, z) degrees of freedom relative to the respective support member. Each mold-cavity insert on the first support member is in face-to-face opposition to a respective mold-cavity insert on the second support member whenever the support members are in face-to-face opposition to each other, such that the respective hemispherical cavities of each opposing pair of inserts form respective spherical ball-cover cavities. A respective z-direction bias is associated with each mold-cavity insert. Also, a respective self-centering device is associated with each opposing pair of inserts. The self-centering device urges movement of at least one mold-cavity insert of the opposing pair in any of at least three degrees of freedom as required to center the mold-cavity inserts of the opposing pair with each other.

Claims

1. A mold-half of a golf-ball-cover casting mold, the mold-half comprising:

a support member extending in x- and y-directions;

a mold-cavity insert defining a substantially hemispherical ball-cover cavity;

a mounting coupling the mold-cavity insert to the support member, the mounting providing floatability of the mold-cavity insert, relative to the support member, in at least three degrees of freedom; and

a self-centering device, associated with the mold-cavity insert, engageable with a mating mold-cavity insert on a facing support member to urge movement of the mold-cavity insert in any of the at least three degrees of freedom as required to center the mold-cavity insert with the mating mold-cavity insert.

2. The mold-half of claim 1, wherein the at least three degrees of freedom comprise x, y, and z degrees of freedom.

3. The mold-half of claim 1, further comprising a bias situated between the mold-cavity insert and the support member.

4. The mold-half of claim 3, wherein the bias is a z-direction bias.

5. The mold-half of claim 4, wherein the z-direction bias comprises a compression spring.

6. The mold-half of claim 1, wherein:

the support member comprises a plate defining a cylindrical bore extending in a z-direction into the support member; and

the mold-cavity insert is situated in the bore with sufficient diametrical clearance to provide the floatability of the mold-cavity insert in the at least three degrees of freedom.

7. The mold-half of claim 1, wherein the self-centering device comprises at least one pin and at least one hole.

8. The mold-half of claim 1, wherein the self-centering device comprises at least one projection having a sloped surface that engages a substantially complementary sloped surface on the mating mold-cavity insert.

9. A mold for casting a golf-ball cover, comprising:

first and second support members that are placeable in face-to-face opposition to each other;

at least one respective mold-cavity insert, defining a respective substantially hemispherical cavity, mounted to each support member so as to provide at least one mating pair of mold-cavity inserts per mold, the mating pair being in face-to-face opposition to each other whenever the support members are in face-to-face opposition to each other such that the respective substantially hemispherical cavities of each mating pair form respective spherical ball-cover cavities;

at least one mold-cavity insert of each mating pair being floatable in at least three degrees of freedom relative to the respective support member;

a respective z-direction bias associated with the floatable mold-cavity insert; and

a respective self-centering device, associated with each mating pair of inserts, urging movement of at least one mold-cavity insert of the mating pair in any of the at least three degrees of freedom as required to center the mold-cavity inserts of the mating pair with each other.

10. The mold of claim 9, wherein the at least three degrees of freedom include x, y, and z degrees of freedom.

11. The mold of claim 9, wherein:

both mold-cavity inserts of each mating pair are floatable in at least three degrees of freedom relative to the respective support member; and

a respective z-direction bias is associated with both floatable mold-cavity inserts.

12. A mold for casting a golf-ball cover, comprising:

first and second support members that are placeable in face-to-face opposition to each other;

at least one respective mold-cavity insert, defining a respective substantially hemispherical cavity, mounted to each support member, the at least one mold-cavity insert being floatable in at least three degrees of freedom relative to the respective support member;

each mold-cavity insert on the first support member being in face-to-face opposition to a respective mold-cavity insert on the second support member whenever the support members are in face-to-face opposition to each other such that the respective substantially hemispherical cavities of each opposing pair of inserts form respective spherical ball-cover cavities;

a respective z-direction bias associated with each mold-cavity insert; and

a respective self-centering device, associated with each opposing pair of inserts, urging movement of at least one mold-cavity insert of the opposing pair in any of the at least three degrees of freedom as required to center the mold-cavity inserts of the opposing pair with each other.

13. The mold of claim 12, wherein the z-direction bias comprises a compression spring.

14. The mold of claim 12, wherein the at least three degrees of freedom comprise x, y, and z degrees of freedom.

15. The mold of claim 12, wherein:

each support member comprises a respective plate defining respective cylindrical bores for the respective mold-cavity inserts; and

each mold-cavity insert is situated in the respective bore with sufficient x-y and z clearance to provide the floatability of the mold-cavity insert in x, y, and z degrees of freedom.

16. The mold of claim 15, wherein:

each mold-cavity insert comprises a cylindrical portion and a flange defining respective a shoulder;

each bore comprises a cylindrical portion and a respective shoulder;

the x-y clearance is diametrical clearance of the cylindrical portion of the insert relative to the cylindrical portion of the bore; and

the z clearance is determined, at least in part, by clearance between the shoulders.

17. The mold of claim 16, wherein the z-direction bias is situated between the shoulders.

18. The mold of claim 17, wherein the z-direction bias comprises a spring-washer.

19. The mold of claim 15, wherein, with respect to each opposing pair of mold-cavity inserts, the self-centering device comprises at least one pin on a first mold-cavity insert and at least one complementary hole on a second mold-cavity insert of the opposing pair.

20. The mold of claim 15, wherein, with respect to each opposing pair of mold-cavity inserts, the self-centering device comprises, on a first mold-cavity insert of the pair, at least one projection having a sloped side that engages a complementary sloped side on a projection of the second mold-cavity insert.

21. The mold of claim 15, wherein, with respect to each opposing pair of mold-cavity inserts, each mold-cavity insert comprises a respective parting surface, the parting surfaces being contact surfaces of the mold-cavity inserts of the opposing pair whenever the support members are in face-to-face opposition to each other.

22. The mold of claim 21, wherein, with respect to each opposing pair of mold-cavity inserts, the z-direction bias urges the parting surfaces together whenever the support members are in face-to-face opposition to each other.

23. The mold of claim 21, wherein, with respect to each opposing pair of mold-cavity inserts, the respective self-centering device associated with each opposing pair of inserts comprises a first portion adjacent the parting surface of one mold-cavity insert, and a second portion, complementary to the first portion, adjacent the parting surface of the other mold-cavity insert.

24. The mold of claim 15, wherein the first and second support members are coupled together in a manner rendering them placeable in face-to-face opposition to each other.

25. The mold of claim 15, wherein each of the first and second support members includes multiple respective mold-cavity inserts.

26. A method for casting a cover on a golf ball, comprising:

mounting at least one opposable pair of first and second mold-cavity inserts, each insert defining a respective substantially hemispherical cavity for casting a respective half of a cover and each insert defining a respective parting surface, to respective support members in a manner providing at least one of the first and second mold-cavity inserts with floatability in at least three degrees of freedom relative to the respective support member;

providing the mold-cavity inserts of the opposable pair with respective self-centering devices;

with respect to the mold-cavity inserts of the opposable pair, adding a castable resin and core to the hemispherical cavities;

moving the support members to position the mold-cavity inserts of the opposable pair face-to-face with each other;

bringing the parting surfaces of the face-to-face mold-cavity inserts into mutual contact such that the hemispherical cavities form a ball-cavity enclosing the resin and core;

as the parting surfaces are brought into mutual contact, mutually engaging the self-centering devices of the face-to-face mold-cavity inserts with each other to center the inserts with each other;

curing the resin to form a covered golf ball; and

opening the mold-cavity inserts and removing the covered golf ball from the ball cavity.

27. The method of claim 26, wherein the at least three degrees of freedom comprise x, y, and z degrees of freedom.

28. The method of claim 26, wherein engaging the self-centering devices comprises automatically displacing, as required, at least one of the face-to-face mold-cavity inserts according to its at least three degrees of freedom, relative to the other insert and relative to the support members, to center the mold-cavity inserts with each other.

29. The method of claim 26, wherein providing the mold-cavity inserts of the opposable pair with respective self-centering devices comprises providing the inserts with pins and conforming holes that mutually engage with each other as the parting surfaces are brought into mutual contact.

30. The method of claim 26, wherein providing the mold-cavity inserts of the opposable pair with respective self-centering devices comprises providing the inserts with sloping surfaces that mutually engage with each other as the parting surfaces are brought into mutual contact.

31. The method of claim 26, further comprising, with respect to the opposable pair of mold-cavity inserts, providing at least one of the inserts with a z-direction bias.