Tire curing bladder

• US 7,144,236 B2
• Filed: 08/23/2004
• Issued: 12/05/2006
• Est. Priority Date: 08/23/2004
• Status: Expired due to Fees

• Current Assignee: Goodyear Tire & Rubber Company
• Original Assignee: Goodyear Tire & Rubber Company
• Inventors: Wang, Yang, Lee, Ching-Chih, Ashton, Susan Lynn, Quijano, Alfonso, Okoye, Ikechukwu Joel
• Primary Examiner(s): Mackey, James P.
• Application Number:
  US10/924,110
• Publication Number:
  US 20060040006A1
• Time in Patent Office: 834 Days
• Field of Search: 425/43, 425/52, 264/315
• US Class Current: 425/52
• CPC Class Codes: B29C 43/3642 Bags, bleeder sheets or cauls for isostatic pressing
• CPC Class Codes: B29D 2030/0655 Constructional or chemical features of the flexible cores
• 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

Abstract

An expandable bladder for shaping a pneumatic tire to be mounted inside a tire curing press has a pair of opposing annular beads and an expansion portion located between the pair of annular beads. The expansion portion of the bladder has a central portion, shoulder portions, and sidewall portions. When the bladder is in a mounted but uninflated mode, the shoulder portions have a radius of curvature less than infinity. At a distance (x) from each end of the central portion, the bladder has an increased thickness in the shoulder and upper sidewall portions.

Claims

1. An expandable bladder for shaping a pneumatic tire to be mounted inside a tire curing machine, the expandable bladder having a toroidal configuration and comprising

a pair of opposing annular beads and an expansion portion located between the pair of annular beads, the expansion portion comprising a central portion, shoulder portions, and sidewall portions, the central portion having a generally constant thickness,

wherein, when the bladder is in a mounted but uninflated mode, the bladder being characterized by:

beginning at a distance (x) from each end of the central portion, and between the opposing annular beads, the shoulder portions and sidewall portions have a gradually increasing thickness.

2. The bladder of claim 1 wherein the distance (x) has a width of at least 5% of the width (F) of the central portion.

3. The bladder of claim 1 wherein the distance (x) has a width of 15–

30% of the width (F) of the central portion.

4. The bladder of claim 1 wherein the ratio of a bladder thickness at the mid-section width Wm to the bladder thickness at the central portion is greater than 1.05.

5. The bladder of claim 1 wherein the ratio of a bladder thickness at the mid-section width Wm to the bladder thickness at the central portion is in the range of 1.20 to 1.40.

6. The bladder of claim 1 wherein the central portion has a width (F) of 20 to 65% of the bladder height (H).

7. The bladder of claim 1 wherein the central portion has a width (F) of 30 to 50% of the bladder height (H).

8. An expandable bladder for shaping a pneumatic tire to be mounted inside a tire curing machine, the expandable bladder having a toroidal configuration and comprising

a pair of opposing annular beads and an expansion portion located between the pair of annular beads, the expansion portion comprising a central portion, shoulder portions, and sidewall portions, the central portion having a generally constant thickness,

wherein, when the bladder is in a mounted but uninflated mode, the bladder being characterized by:

beginning at a distance (x) of 5 to 30% of the width (F) of the central portion, from each end of the central portion, the shoulder portions and the upper portion of the sidewall portions have a localized increased thickness in comparison to the central portion of the bladder.

9. The bladder of claim 8 wherein the distance (x) has a width of 15–

30% of the width (F) of the central portion.

10. The bladder of claim 8 wherein the maximum thickness of the localized increased thickness has a thickness value of at least 1.05 times the thickness of the central portion of the bladder.

11. The bladder of claim 8 wherein the maximum thickness of the localized increased thickness has a thickness value of 1.20 to 1.75 times the thickness of the central portion of the bladder.

12. The bladder of claim 8 wherein the central portion has a width (F) of 20 to 65% of the bladder height (H).

13. The bladder of claim 8 wherein the central portion has a width (F) of 30 to 50% of the bladder height (H).