Method and apparatus for improved tread splicing

Patent metadata

Field	Value
Publication number	US-2024165902-A1
Application number	US-202418424275-A
Country	US
Kind code	A1
Filing date	Jan 26, 2024
Priority date	May 26, 2015
Publication date	May 23, 2024
Grant date	—

Abstract

A mold for molding a tire tread comprises a plurality of mold segments. Each of the plurality of mold segments includes an integer number of tread pitch repetitions. The plurality of mold segments are structured to be coupled to each other end-to-end so as to form the mold such that the mold includes an integer number of tread pitches. The mold also includes at least one mold end segment positioned on at least one end of the mold and has a mold end segment length shorter than a length of each of the plurality of mold segments.

First claim

1 - 23 . (canceled)

24 . A method of forming a mold for molding a tire tread, the method comprising:
positioning a first mold segment between a first end segment and a second end segment, the first mold segment comprising a first body portion, a third body portion, and a second body portion positioned between the first body portion and the third body portion, the first end segment comprising the second body portion and the third body portion, and the second end segment comprising the first body portion and the second body portion.

25 . The method of claim 24 , wherein:
the first end segment comprises a first non-integer number of tread patterns; the second end segment comprises a second non-integer number of tread patterns; and the sum of the first non-integer number and the second non-integer number is an integer.

26 . The method of claim 24 , further comprising:
forming the first end segment from a second mold segment by removing the first body portion from the second mold segment.

27 . The method of claim 26 , wherein the second mold segment comprises a cut-mark denoting a boundary between the first body portion and the second body portion, the boundary extending through a lug of the tread pattern, the method further comprising:
cutting the second mold segment along the boundary to form the first end segment, the first end segment having a first non-integer number of tread pitches.

28 . The method of claim 26 , further comprising:
forming the second end segment from a third mold segment by removing the third body portion from the third mold segment.

29 . The method of claim 28 , wherein the third mold segment comprises a cut-mark denoting a boundary between the third body portion and the second body portion, the boundary extending through a lug of the tread pattern, the method further comprising:
cutting the third mold segment along the boundary to form the second end segment, the second end segment having a second non-integer number of tread pitches.

30 . The method of claim 24 , further comprising:
coupling the first mold segment to the first end segment such that the third body portion of the first end segment abuts the first body portion of the first mold segment.

31 . A method of forming a mold for forming a tire tread, the method comprising:
providing a first mold segment having a first integer number of tread pitch repetitions; providing a first end segment having a first non-integer number of tread pitch repetitions, the first integer number being greater than the first non-integer number; and positioning the first mold segment in confronting relation with the first end segment such that a tread pattern of the first mold segment aligns with a tread pattern of the first end segment.

32 . The method of claim 31 , further comprising:
providing a second mold segment having the first integer number of tread pitch repetitions; providing a second end segment having a second non-integer number of tread pitch repetitions, the second non-integer number being less than the first integer number; and positioning the second mold segment in confronting relation with the second end segment such that a tread pattern of the second mold segment aligns with a tread pattern of the second end segment.

33 . The method of claim 32 , wherein the second non-integer number is different from the first non-integer number.

34 . The method of claim 32 , further comprising positioning a third mold segment between the first mold segment and the second mold segment.

35 . The method of claim 31 , wherein the first end segment and the first mold segment cooperate to define a unitary mold, the method further comprising:
loading the unitary mold with a tread preform; pressing the tread preform in the unitary mold; curing the tread preform to form a tire tread; cutting a portion of at least one end of the tire tread so as to form a cut-end of the tire tread; positioning the tire tread around a tire; splicing the cut end of the tire tread with an opposite end of the tire tread; and curing the tire tread and the tire so as to form a retreaded tire.

Assignees

• Bridgestone Bandag Llc

Inventors

• Otting Robert G
• Westaway Terry A

Classifications

• B29D30/52 Primary

  Unvulcanised treads, e.g. on used tyres; Retreading (apparatus for forming {treads by extrusion B29C48/00; apparatus for} vulcanising treads B29C35/02; apparatus characterised by the means for holding wheels or parts thereof B60B30/00) · CPC title

• B29D30/56

  Retreading with prevulcanised tread {(B29D30/542 takes precedence)} · CPC title

• B60C11/0318

  irregular patterns with particular pitch sequence · CPC title

• B29D2030/0653

  Exchanging moulds in the presses · CPC title

• B29D2030/0609

  the moulds being made of a plurality of laminations, e.g. thin plates, adjacent one another, so as to create the moulding cavity · CPC title