TIRE CURING BLADDER

• US 20090159215A1
• Filed: 09/25/2008
• Published: 06/25/2009
• Est. Priority Date: 12/20/2007
• Status: Active Grant

• Current Assignee: Goodyear Tire & Rubber Company
• Original Assignee: Goodyear Tire & Rubber Company
• Inventors: Agostini, Giorgio, Corvasce, Filomeno Gennaro, Russo, Massimo Di Giacomo
• Granted Patent: US 8,057,204 B2
• Time in Patent Office: Days
• US Class Current: 156/421.600
• CPC Class Codes: B29C 33/505 cores or mandrels, e.g. inflatable B29C33/0016 takes precedence; for winding and joining B29C53/824; for supporting articles during joining B29C66/634; flexible cores for vulcanizing tyres B29D30/0654
• 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 30/0601 Vulcanising tyres; Vulcanising presses for tyres
• 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 is provided. The bladder in an unmounted, relaxed state has a shaped body having a pair of opposed annular beads, said body further comprising a central portion, sidewall portions, and shoulder portions interposed between the central portion and the sidewall portions, wherein the body is defined by an outer contour surface and an inner contour surface, wherein the central portion has gauge which increases to a maximum value axially inward of the shoulder portion, and wherein the bladder gauge in the shoulder is less than the maximum value, and wherein the bladder gauge increases from the shoulder to the bead.

Claims

1. An expandable bladder for shaping a pneumatic tire to be mounted in a tire curing press, the bladder in an unmounted, relaxed state comprises:

a shaped body having a pair of opposed annular beads, said body further comprising a central portion, sidewall portions, and shoulder portions interposed between the central portion and the sidewall portions, wherein the body is defined by an outer contour surface and an inner contour surface, wherein outer contour surface is shaped differently than the inner contour surface.

2. The bladder of claim 1 wherein the shoulder radius of the inner contour surface is substantially smaller than the central portion radius.

3. The bladder of claim 1 wherein the shoulder radius of the outer contour surface is substantially smaller than the central portion radius.

4. The bladder of claim 1 wherein the bladder gauge of the central portion decreases from a center point to a point between the center point and the shoulder portion.

5. The bladder of claim 1 wherein the bladder gauge of the central portion decreases from a center point to a minimum point located between the center point and the shoulder portion, and then the bladder gauge increases from said minimum to a maximum point located radially inward of the shoulder portion.

6. The bladder of claim 1 wherein the bladder gauge increases from the shoulder portion to the bead area.

7. The bladder of claim 1 wherein the ratio of the shoulder gauge g3 to the maximum center portion gauge g4 is in the range of about 0.1 to about 1.

8. The bladder of claim 1 wherein the center portion of the bladder has a minimum gauge g2 and a maximum gauge g4, wherein the ratio of g2/g4 is in the range of about 0.4 to about 1.3.

9. The bladder of claim 1 wherein the ratio of the shoulder gauge g3 to the maximum center portion gauge g4 is in the range of about 0.3 to about 0.7.

10. The bladder of claim 1 wherein the maximum bladder gauge is located between the center portion and the shoulder.

11. The bladder of claim 1 wherein the minimum bladder gauge is located between the center portion and the shoulder.

12. The bladder of claim 1 wherein the minimum bladder gauge is located between the center portion and the midpoint of the central portion.

14. The expandable bladder of claim 10 wherein the bladder has a central portion wherein the thickness of the bladder decreases from its center to a minimum point, and then increases to a maximum value of the central portion at a location radially inward of the shoulder portion.

13. An expandable bladder for shaping a pneumatic tire to be mounted in a tire curing press, the bladder in an unmounted, relaxed state comprises:

a shaped body having a pair of opposed annular beads, said body further comprising a central portion, sidewall portions, and shoulder portions interposed between the central portion and the sidewall portions, wherein the body is defined by an outer contour surface and an inner contour surface, wherein the central portion has gauge which increases to a maximum value axially inward of the shoulder portion, and wherein the bladder gauge in the shoulder is less than the maximum value, and wherein the bladder gauge increases from the shoulder to the bead.