Bladder for tire building apparatus and method of making the same

• US 3,990,930 A
• Filed: 08/21/1975
• Issued: 11/09/1976
• Est. Priority Date: 09/09/1971
• Status: Expired due to Term

• Current Assignee: Goodyear Tire & Rubber Company
• Original Assignee: Goodyear Tire & Rubber Company
• Inventors: Schmit, Georges
• Primary Examiner(s): Powell, William A.
• Assistant Examiner(s): Kittle, John E.
• Application Number:
  US05/606,629
• Time in Patent Office: 446 Days
• Field of Search: 156/110 R, 156/123 R, 156/128 R, 156/128 I, 156/133, 156/394 R, 156/414, 156/416
• US Class Current: 156/123
• CPC Class Codes: B29C 2043/3649 Inflatable bladders using gas or fluid and related details
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 43/3642 Bags, bleeder sheets or cauls for isostatic pressing
• CPC Class Codes: B29D 2030/2614 Bladders associated with the building drum, e.g. bladders used for the toroidal expansion, bladders for turning-up the plies
• CPC Class Codes: B29D 30/26 Accessories or details, e.g. membranes, transfer rings
• CPC Class Codes: B29K 2021/00 Use of unspecified rubbers as moulding material
• CPC Class Codes: B29K 2105/101 Oriented
• CPC Class Codes: B29L 2022/025 Bladders

Abstract

A bladder for use in conjunction with a tire building drum, said bladder having cords extending substantially parallel to the rotational axis of the bladder and including two belt plies of square woven fabric extending circumferentially about the bladder. The bladder is manufactured by first providing an at least partially cured cylindrical membrane reinforced with cords extending substantially parallel to the rotational axis of the membrane. The membrane is then expanded to a toroidal configuration and an uncured belt structure is applied to the expanded membrane. The membrane is then contracted to the cylindrical configuration and the belt structure is cured.

Claims

1. A method of making a bladder for use in conjunction with a tire building drum comprising:

(a) providing an at least partially cured generally cylindrical elastomeric membrane reinforced with parallel cords running generally axially of the membrane, (b) expanding the central portion of said membrane, (c) adhering a circumferentially extending belt to the surface of said membrane midway between the axially outer ends of the membrane, (d) permitting said membrane to contact to its generally cylindrical configuration and draw the belt radially inwardly to a reduced diameter, and (e) curing the belt while said membrane is in a generally cylindrical configuration.

2. A method as claimed in claim 1, wherein the belt is applied to the radially outer surface of the membrane.

3. A method as claimed in claim 1, wherein the central portion membrane is expanded, prior to adhering the belt to the membrane, to a diameter which is within one-half an inch of the maximum expanded diameter of the bladder during its ultimate use in conjunction with a tire building drum.

4. A method as claimed in claim 3, wherein the belt is adhered to the radially outer surface of the membrane.

5. A method as claimed in claim 1 further including providing said circumferentially extending belt with a crossed cord reinforcing structure with the cords in said reinforcing structure extending at an angle of between 35°

and 60°

with respect to planes perpendicular to the rotational axis of the bladder and, while drawing the belt radially inwardly to a reduced diameter, increasing the angle said cords makes with a plane perpendicular to the rotational axis of the tire.

6. A method as claimed in claim 5 wherein the cords in said belt reinforcing structure are arranged in a square woven configuration and extend at an angle of about 45°

with respect to said planes perpendicular to the rotational axis of the tire when said sleeve is radially expanded and when said belt is arranged on said membrane.

7. A method as claimed in claim 4 further including providing said circumferentially extending belt with a crossed cord reinforcing structure with the cords in said reinforcing structure extending at an angle of between 35°

and 60°

with respect to planes perpendicular to the rotational axis of the bladder and, while drawing the belt radially inwardly to a reduced diameter, increasing the angle said cords make with a plane perpendicular to the rotational axis of the tire.

8. A method as claimed in claim 7 wherein the cords in said belt reinforcing structure are arranged in a square woven configuration and extend at an angle of about 45°

with respect to said planes perpendicular to the rotational axis of the tire when said sleeve is radially expanded and when said belt is arranged on said membrane.