Tire retreading bladder

• US 4,293,293 A
• Filed: 09/15/1980
• Issued: 10/06/1981
• Est. Priority Date: 05/02/1979
• Status: Expired due to Term

• Current Assignee: Louise J. Macmillan
• Original Assignee: Donald Macmillan & Son, Inc.
• Inventors: MacMillan, Kenneth T.
• Primary Examiner(s): Flint, Jr., J. Howard
• Application Number:
  US06/187,339
• Time in Patent Office: 386 Days
• Field of Search: 425/17, 425/19, 425/20, 425/21, 425/22, 425/23, 425/25, 425/36, 425/43, 425/52, 425/58, 425/812, 249/134
• US Class Current: 425/23
• CPC Class Codes: B29C 43/104 the mould cavity lying totally outside the axis of symmetry, e.g. toroidal moulds
• CPC Class Codes: B29D 2030/0655 Constructional or chemical features of the flexible cores
• CPC Class Codes: B29D 2030/582 Venting air inclusions, e.g. air trapped between tread and carcass
• CPC Class Codes: B29D 30/0654 Flexible cores therefor, e.g. bladders, bags, membranes, diaphragms elastic cores or mandrels for shaping of plastics B29C33/505; bags for isostatic pressing in compression moulding B29C43/12, B29C43/3642
• CPC Class Codes: B29D 30/54 Retreading
• CPC Class Codes: Y10S 425/812 Venting

Abstract

A tire retreading bladder which includes a generally angular member of a U-shaped cross-sectional configuration defined by a bight portion and a pair of legs with the annular member defining an interior volume, each leg terminating in a terminal edge of a generally circular configuration, each leg having interior and exterior surfaces, a plurality of pairs of closely adjacent ribs along the exterior surfaces for venting air from between such exterior surfaces and an interior surface of an associated tire adapted to receive therewithin the bladder, each pair of ribs setting off a venting groove therebetween, and venting means further including transverse venting slots disposed lengthwise along the ribs.

Claims

1. A tire retreading bladder comprising a generally annular member of a U-shaped cross-section defined by a bight portion and a pair of legs, said annular member defining an interior volume, each leg terminating in a terminal edge of a generally circular configuration, each leg having interior and exterior surfaces, means disposed along each of said exterior surfaces for venting air from between such exterior surfaces and an interior surface of an associated tire adapted to receive therewithin said bladder, each of said venting means on each of said exterior surfaces having a radially inboard portion terminating radially short of the associated terminal edge, each exterior surface defining between said radially inboard portions of each venting means and the associated terminal edge a generally smooth uninterrupted annular sealing surface, said venting means being in the form of a plurality of pairs of closely adjacent ribs with each pair of ribs setting off a venting groove therebetween, and said venting means further including transverse venting slots being disposed lengthwise along said ribs.

2. The tire retreading bladder as defined in claim 1 wherein each pair of ribs and associated venting groove on said exterior surfaces merge with each other across said bight portion.

3. The tire retreading bladder as defined in claim 1 wherein said slots in the ribs of each pair of ribs are in generally radially offset relationship.

4. The tire retreading bladder as defined in claim 1 wherein each groove is defined by a surface having a lowermost surface portion disposed between said exterior and interior surfaces.

5. The tire retreading bladder as defined in claim 1 wherein said slots in the ribs of each pair of ribs are in generally radially offset relationship, and each groove is defined by a surface having a lowermost surface portion disposed between said exterior and interior surfaces.

6. A retreading mold comprising a pair of relatively movable platens, matrix means carried by each platen, first and second bead aligner wheels carried by a respective first and second of said platens, said bead aligner wheels being in opposed relationship to each other, an annular bladder disposed between said platens, said annular bladder having first and second innermost peripheral marginal portions, said bladder being generally housed within said matrix means, said first and second innermost peripheral marginal portions being in overlying relationship upon said first and second bead aligner wheels, said annular bladder being defined by a bight portion and a pair of legs with said pair of legs terminating in said first and second innermost peripheral marginal portions, each leg having interior and exterior surfaces, means disposed along each of said exterior surfaces for venting air from between such exterior surfaces and an interior surface of an associated tire adapted to receive therewithin the bladder, each of said venting means on each of said exterior surfaces having a radially inboard portion terminating radially short of an associated one of the first and second innermost peripheral marginal portions, each exterior surface defining between said radially inboard portions of each venting means and the associated innermost peripheral marginal portion thereof a generally smooth uninterrupted annular sealing surface, the venting means being in the form of a plurality of closely adjacent ribs with each pair of ribs setting off a venting groove therebetween, and said venting means further including transverse venting slots disposed lengthwise along said ribs.

7. The retreading mold as defined in claim 6 wherein each pair of ribs and associated venting groove on said exterior surfaces merge with each other across said bight portion.

8. The retreading mold as defined in claim 6 wherein said slots in the ribs of each pair of ribs are in generally radially offset relationship.

9. The retreading mold as defined in claim 6 wherein each groove is defined by a surface having a lowermost surface portion disposed between said exterior and interior surfaces.

10. The retreading mold as defined in claim 6 wherein said slots in the ribs of each pair of ribs are in generally radially offset relationship, and each groove is defined by a surface having a lowermost surface portion disposed between said exterior and interior surfaces.