Transmission belt and continuously variable transmission, method for designing element, and method for producing element

A method for producing a plurality of elements of a transmission belt that includes the plurality of elements each including a body part, a pair of side surfaces located at both edges in a width direction of the body part, and a saddle surface located between the pair of side surfaces in the width direction;

• and a ring that circularly puts together the plurality of elements by an inner circumferential surface of the ring coming into contact with each of the saddle surfaces of the plurality of elements, and that is wound around V-shaped grooves of a pair of pulleys of a continuously variable transmission to transmit power, the method comprising:
• setting a pulleys' specification including an opening angle of the pulleys, an elements' specification including flank angles, each being an angle formed between the pair of side surfaces, and an analysis condition including input torque of the continuously variable transmission, and deriving, for a plurality of different flank angles, distributions of friction forces in a radial direction of the ring exerted between the pair of side surfaces and the pulleys, by analysis based on the pulleys' specification, the elements' specification, and the analysis condition;
• deriving, for the plurality of flank angles, rotational moments at a center of pitching of the elements from friction force distributions derived for the plurality of flank angles;
• determining a flank angle suitable for the continuously variable transmission, based on the rotational moments derived for the plurality of flank angles;
• forming a die based on the determined flank angle;
• and
• forming outside shapes of the elements by performing press working using the formed die.