Toothed belt for use with oil and relative timing control system

Timing control system for a motor vehicle comprising at least one driving pulley, one driven pulley, a toothed belt adapted for use substantially continuous contact with oil or partly immersed in oil, and materials for maintaining said toothed belt in an oil-wet condition;

• said toothed belt comprising a body, and one or more teeth extending from at least a first surface of said body, said teeth being covered by a first fabric, said first fabric is externally coated by a first resistant layer, which comprises a fluorinated plastomer, a first elastomeric material, and a vulcanizing agent;
• and in that said fluorinated plastomer is present in said first resistant layer in an amount greater than said first elastomeric material, and a plurality of resistant inserts, wherein said resistant inserts comprise twisted yarns produced from fibers of at least a first and a second material and said first fibrous material entirely surrounds said second fibrous material;
• said first and second materials are chosen from the group consisting of glass fibers, aramid fibers, polyester fibers, PBO fibers, and carbon fibers;
• wherein the twisted yarns form an insert of said resistant inserts with dimensions between 0.7 and 1.4 mm,
• said body comprising as main elastomeric material a copolymer formed from a diene and from a monomer containing nitrile groups in a percentage between 33 and 49 weight percent with respect to the final copolymer.

A method of providing a belt for use with oil, the method comprising:

• providing an oil-wet environment,
• providing a toothed belt to operate in said oil-wet environment, said belt comprising:
• a body,
• a plurality of teeth extending from at leas a first, surface of said body, said teeth being coated by a first fabric, said fabric, said first fabric is externally coated by a first resistant layer, which comprises a fluorinated plastomer, a first elastomeric material, and a vulcanizing agent;
• and in that said fluorinated plastomer is present in said first resistant layer in an amount greater than said first elastomeric material, and
• a plurality of resistant inserts;
• wherein said resistant inserts comprise twisted yarns produced from fibers of at least a first and a second material and said first fibrous material entirely surrounds said second fibrous material;
• said first and second materials are chosen from the group consisting of glass fibers, aramid fibers, polyester fibers, PBO fibers, and, carbon fibers;
• wherein the twisted yarns form an insert of said resistant inserts with dimensions between 0.7 and 1.4 mm;
• said body comprising as main elastomeric material a copolymer formed from a diene and from a monomer containing nitrile groups in a percentage between 33 and 49 weight percent with respect to the final copolymer.