# US 3,990,930 A · Bladder for tire building apparatus and method of making the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 3,990,930 A - Document ID: US3990930A - Status: Granted - Kind: A - Application number: 05/606,629 - Filed: 1975-08-21 - Granted: 1976-11-09 - Earliest claimed: 1971-09-09 - Assignees: The Goodyear Tire & Rubber Company - Inventors: Georges Schmit - Web page: https://patentgrep.com/patent/US3990930A ## CPC - B29D 30/26: Accessories or details, e.g. membranes, transfer rings - B29C 43/3642: {Bags, bleeder sheets or cauls for isostatic pressing} - B29C 2043/3649: {Inflatable bladders using gas or fluid and related details} - B29C 2791/001: Shaping in several steps - B29D 2030/2614: {Bladders associated with the building drum, e.g. bladders used for the toroidal expansion, bladders for turning-up the plies} - B29K 2021/00: Use of unspecified rubbers as moulding material - B29K 2105/101: {Oriented} - B29L 2022/025: {Bladders} - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## 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 ### Claim 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. ### Claim 2 (depends on 1) A method as claimed in claim 1, wherein the belt is applied to the radially outer surface of the membrane. ### Claim 3 (depends on 1) 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. ### Claim 4 (depends on 3) A method as claimed in claim 3, wherein the belt is adhered to the radially outer surface of the membrane. ### Claim 5 (depends on 1) 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.degree. and 60.degree. 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. ### Claim 6 (depends on 5) 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.degree. 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. ### Claim 7 (depends on 4) 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.degree. and 60.degree. 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. ### Claim 8 (depends on 7) 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.degree. 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.