# US 2009/0260515 A1 · Method for producing a rubber diaphragm, especially for motor vehicle brakes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260515 A1 - Document ID: US20090260515A1 - Status: Published application - Kind: A1 - Application number: 12/411,372 - Filed: 2009-03-25 - Published: 2009-10-22 - Earliest claimed: 2008-03-25 - Assignees: Xianqiao ZHU - Inventors: Xianqiao ZHU; Qichao TANG; Binghong QIN; Zhenxin YANG - Web page: https://patentgrep.com/patent/US20090260515A1 ## CPC - B29C 43/04: using movable moulds - B29C 43/203: {Making multilayered articles} - B29K 2007/00: Use of natural rubber as moulding material - 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 ## Abstract A method for producing a rubber diaphragm, comprising: (a) preparing materials; (b) primary forming: putting a first rubber film into a lower mold cavity of a diaphragm mold, covering the film with a canvas, positioning the canvas via a mold ring, switching on a primary upper mold on a vulcanizer, pushing the mold into a center of a hot plate of the vulcanizer, and performing primary forming for 30-40 seconds under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa; and (c) secondary forming and curing: taking the mold out, removing the upper mold, putting the second rubber film into a mold cavity and switching on a secondary upper mold, pushing the mold into a center of the hot plate, and performing secondary forming and curing for 5-5.5 minutes under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa. A rubber diaphragm produced by this method. ## Claims ### Claim 1 A method for producing a rubber diaphragm for a vehicle brake, comprising: (a) preparing materials: producing, measuring and cutting a first rubber film, a second rubber film and a canvas; (b) primary forming: putting said first rubber film into a lower mold cavity of a diaphragm mold, covering said film with said canvas, positioning said canvas via a mold ring, switching on a primary upper mold on a vulcanizer, pushing said mold into a center of a hot plate of said vulcanizer, and performing primary forming for 30-40 seconds under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa, automatic opening and exhausting being performed for 3-4 times or vacuum pumping being performed; (c) secondary forming and curing: taking said mold out, removing said upper mold, putting said second rubber film into a mold cavity and switching on a secondary upper mold, pushing said mold into a center of said hot plate, and performing secondary forming and curing for 5-5.5 minutes under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa, automatic opening and exhausting being performed for 3-4 times or vacuum pumping being performed; and (d) performing mold opening, and then trimming said mold after said mold is cooled. ### Claim 2 (depends on 1) The method of claim 1, wherein the thickness of said first rubber film is 3.5-4.5 mm. ### Claim 3 (depends on 1) The method of claim 1, wherein the thickness of said second rubber film is 3.5-4.5 mm. ### Claim 4 (depends on 1) The method of claim 1, wherein the size of said canvas is between 270×270 mm and 320×320 mm. ### Claim 5 (depends on 1) The method of claim 1, wherein said vulcanizer is a press rubber vulcanizer with an automatic opening and exhausting function. ### Claim 6 (depends on 1) The method of claim 1, wherein said vulcanizer is a vacuum rubber vulcanizer. ### Claim 7 (depends on 1) The method of claim 1, wherein the rubber diaphragm has sufficient strength and durability to be used in a heavy truck above 3 tons. ### Claim 8 (depends on 1) The method of claim 1, wherein the frustoconical angle of inclination (α) of the rubber diaphragm is less than or equal to 20°, and the depth (d) of the rubber diaphragm is greater than or equal to 40 mm. ### Claim 9 (depends on 1) The method of claim 1, wherein the frustoconical angle of inclination (α) of the rubber diaphragm is greater than or equal to 20°, and the depth (d) of the rubber diaphragm is less than or equal to 40 mm. ### Claim 10 A method for producing a rubber diaphragm for a vehicle brake, comprising: (a) primary forming: putting a first rubber film into a lower mold cavity of a diaphragm mold, covering said first rubber film with a canvas, positioning said canvas via a mold ring, pushing said mold into a center of a hot plate of a vulcanizer, and performing primary forming for 30-40 seconds under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa, during primary forming automatically opening and exhausting for 3-4 times or vacuum pumping; and (b) secondary forming and curing: taking said mold out, removing said upper mold, putting a second rubber film into a mold cavity, pushing said mold into a center of the hot plate, and performing secondary forming and curing for 5-5.5 minutes under a setting temperature of 152-157° C. and holding pressure of 16-18 MPa, during secondary forming and curing automatically opening and exhausting for 3-4 times or vacuum pumping. ### Claim 11 (depends on 10) The method of claim 10, wherein the thickness of said first rubber film is 3.5-4.5 mm. ### Claim 12 (depends on 10) The method of claim 10, wherein the thickness of said second rubber film is 3.5-4.5 mm. ### Claim 13 (depends on 10) The method of claim 10, wherein the size of said canvas is between 270×270 mm and 320×320 mm. ### Claim 14 (depends on 10) The method of claim 10, wherein said vulcanizer is a press rubber vulcanizer with an automatic opening and exhausting function. ### Claim 15 (depends on 10) The method of claim 10, wherein said vulcanizer is a vacuum rubber vulcanizer. ### Claim 16 (depends on 10) The method of claim 10, wherein the rubber diaphragm has sufficient strength and durability to be used in a heavy truck above 3 tons. ### Claim 17 (depends on 10) The method of claim 10, wherein the frustoconical angle of inclination (α) of the rubber diaphragm is less than or equal to 20°, and the depth (d) of the rubber diaphragm is greater than or equal to 40 mm. ### Claim 18 (depends on 10) The method of claim 10, wherein the frustoconical angle of inclination (α) of the rubber diaphragm is greater than or equal to 200, and the depth (d) of the rubber diaphragm is less than or equal to 40 mm. ### Claim 19 (depends on 10) A rubber diaphragm for a vehicle brake produced by the method of claim 10, said diaphragm having a frustoconical angle of inclination (α) and a depth (d), wherein the frustoconical angle of inclination (α) of the rubber diaphragm is less than or equal to 200, and the depth (d) of the rubber diaphragm is greater than or equal to 40 mm. ### Claim 20 (depends on 10) A rubber diaphragm for a vehicle brake produced by the method of claim 10, said diaphragm having a frustoconical angle of inclination (α) and a depth (d), wherein the frustoconical angle of inclination (α) of the rubber diaphragm is greater than or equal to 200, and the depth (d) of the rubber diaphragm is less than or equal to 40 mm.