US 11,654,645 B2
Friction transmission belt and method for producing same
Takafumi Tamura, Hyogo (JP); Hiroki Takechi, Hyogo (JP); and Arata Hasegawa, Hyogo (JP)
Assigned to Mitsuboshi Belting Ltd., Kobe (JP)
Appl. No. 16/496,314
Filed by Mitsuboshi Belting Ltd., Kobe (JP)
PCT Filed Mar. 20, 2018, PCT No. PCT/JP2018/011189
§ 371(c)(1), (2) Date Sep. 20, 2019,
PCT Pub. No. WO2018/174093, PCT Pub. Date Sep. 27, 2018.
Claims priority of application No. JP2017-054859 (JP), filed on Mar. 21, 2017; and application No. JP2018-041186 (JP), filed on Mar. 7, 2018.
Prior Publication US 2020/0009813 A1, Jan. 9, 2020
Int. Cl. B29D 29/08 (2006.01); B32B 23/02 (2006.01); B32B 5/26 (2006.01); B32B 5/24 (2006.01); F16G 1/08 (2006.01); F16G 5/20 (2006.01); B29L 31/00 (2006.01)
CPC B29D 29/08 (2013.01) [B32B 5/24 (2013.01); B32B 5/266 (2021.05); B32B 23/02 (2013.01); B29K 2023/06 (2013.01); B29L 2031/7094 (2013.01); B32B 2433/04 (2013.01); F16G 1/08 (2013.01); F16G 5/20 (2013.01)] 2 Claims
OG exemplary drawing
 
1. A production method for a frictional power transmission belt, the method comprising:
a winding step of sequentially winding, around a cylindrical drum, a sheet for forming a tension layer, a tension member, an unvulcanized rubber sheet for forming a compression rubber layer, and a sheet structure for forming a fiber/resin mixture layer and a fiber layer, wherein the winding step results in a multilayer material; and
a vulcanization molding step of pressing the multilayer material against a mold to vulcanize and mold the unvulcanized rubber sheet,
wherein, in the vulcanization molding step, the unvulcanized rubber sheet is pre-heated, at a temperature lower than a vulcanization temperature of the unvulcanized rubber sheet, and then vulcanized, and
wherein the winding step, when winding the sheet structure, comprises:
winding a first nonwoven fabric comprising a first thermoplastic resin having a
softening point or a melting point not higher than the vulcanization temperature;
winding a second nonwoven fabric comprising heat-resistant fibers;
winding a third nonwoven fabric comprising a second thermoplastic resin having a softening point or a melting point not higher than the vulcanization temperature; and
winding a fourth nonwoven fabric comprising hydrophilic heat-resistant fibers.