This method for manufacturing a ring is a method for manufacturing an endless metal ring for a continuously variable transmission using a transmission belt that is formed by binding a plurality of elements with the ring. The method includes: a welding step of butt welding ends of a metal strip to form an endless tubular body; a solution treatment step of solution-treating the welded tubular body; a cutting step of cutting the solution-treated tubular body with laser light into ring bodies with a predetermined width; a lateral end processing step of pressing a grinding wheel against a lateral end of the cut ring body to remove a heat-affected zone formed by the cutting step and form the lateral end into a convex arc shape; and a rolling step of adjusting the ring body with the processed lateral end to a predetermined thickness.

In a method for cleaning a portion to be welded in which a first portion (Pa) to be welded and a second portion (Pb) to be welded, which are to be joined by butt welding, are cleaned, the first and second portions (Pa, Ph) to be welded are cleaned before the butt welding by injecting, with the first and second portions (Pa, Pb) to be welded abutting on each other, plasma produced from a gas containing oxygen into a groove between the first portion (Pa) to be welded and the second portion Pb) to be welded.

A first recessing-and-projecting line is formed in a trailing end of a preceding first belt material and a second recessing-and-projecting line is formed in a leading end of a newly fed out second belt material, and the first recessing-and-projecting line and the second recessing-and-projecting line are fitted to each other, thereby joining the first belt material and the second belt material. Note that the first recessing-and-projecting line and the second recessing-and-projecting line pass through a holding section that holds an element in the first belt material or the second belt material.

A first recessing-and-projecting line is formed in a trailing end of a preceding first belt material and a second recessing-and-projecting line is formed in a leading end of a newly fed out second belt material, and the first recessing-and-projecting line and the second recessing-and-projecting line are fitted to each other, thereby joining the first belt material and the second belt material. Note that the first recessing-and-projecting line and the second recessing-and-projecting line pass through a holding section that holds an element in the first belt material or the second belt material.

Among a plurality of layers of metal rings, an inner circumferential projection is formed on an inner circumferential surface of at least one metal ring, and an outer circumferential projection is formed on an outer circumferential surface of the outermost metal ring. Thus, cracks extending from a surface of the metal ring can be arrested by the inner circumferential projection and the outer circumferential projection. Moreover, the outer circumferential projection of the outermost metal ring that does not abut against any other members is set to have a smaller projection height than the inner circumferential projection that abuts against other members. Thus, even if the inner circumferential projection wears by abutting against the other members, the inner circumferential projection can remain and arrest extension of the cracks; also, the projection height of the outer circumferential projection is reduced to enhance flatness of the outer circumferential surface of the metal ring.

Among a plurality of layers of metal rings, an inner circumferential projection is formed on an inner circumferential surface of at least one metal ring, and an outer circumferential projection is formed on an outer circumferential surface of the outermost metal ring. Thus, cracks extending from a surface of the metal ring can be arrested by the inner circumferential projection and the outer circumferential projection. Moreover, the outer circumferential projection of the outermost metal ring that does not abut against any other members is set to have a smaller projection height than the inner circumferential projection that abuts against other members. Thus, even if the inner circumferential projection wears by abutting against the other members, the inner circumferential projection can remain and arrest extension of the cracks; also, the projection height of the outer circumferential projection is reduced to enhance flatness of the outer circumferential surface of the metal ring.

Disclosed is an endless metal belt (101, 102) which has a length/circumference (l1) and a width (b1) and which is produced by welding a number of individual metal belt parts (2). A rolling direction (3) of the individual metal belt parts (2) and the weld seams (4) extend transversely to the length/circumference (l1) of the metal belt (101, 102). Also disclosed is a method for producing an endless metal belt (101, 102) of said type.

Disclosed is an endless metal belt (101, 102) which has a length/circumference (l1) and a width (b1) and which is produced by welding a number of individual metal belt parts (2). A rolling direction (3) of the individual metal belt parts (2) and the weld seams (4) extend transversely to the length/circumference (l1) of the metal belt (101, 102). Also disclosed is a method for producing an endless metal belt (101, 102) of said type.

A metal element for continuously variable transmission and method of producing the same are provided. A rear surface of a metal element includes first contact parts formed at top positions on the outer side in the radial direction of a saddle surface on left and right sides of an ear part, a second contact part formed in a neck part, and third contact parts formed at a top position of the saddle surface on left and right sides of the body part. In a chord on the driving force transmission side of the metal belt, the first to third contact parts are able to be brought into contact with a front surface of another metal element adjacent to the rear side. A plate thickness of the metal element at the second contact part is smaller than the first contact part and is larger than the third contact part.

A metal element for continuously variable transmission and method of producing the same are provided. A rear surface of a metal element includes first contact parts formed at top positions on the outer side in the radial direction of a saddle surface on left and right sides of an ear part, a second contact part formed in a neck part, and third contact parts formed at a top position of the saddle surface on left and right sides of the body part. In a chord on the driving force transmission side of the metal belt, the first to third contact parts are able to be brought into contact with a front surface of another metal element adjacent to the rear side. A plate thickness of the metal element at the second contact part is smaller than the first contact part and is larger than the third contact part.