Toroidal-type continuously variable transmission

A toroidal-type continuously variable transmission comprising:

• first and second disks supported concentrically with each other and rotatably, with their respective inner surfaces disposed opposed to each other;
• trunnions respectively swingable about associated pivot shafts disposed at positions twisted with respect to the center axes of said first and second disks;
• shift shafts respectively supported in the intermediate portions of support plate portions respectively forming said trunnions in such a manner that they respectively project from their associated inner surfaces of said support plate portions;
• power rollers respectively held by and between said first and second disks in such a manner that they are rotatably supported on the peripheries of said shift shafts;
• thrust rolling bearings attachedly disposed on the outer surfaces of said power rollers for permitting said power rollers to rotate while supporting thrust-direction loads applied to said power rollers;
• and
• a pair of bent wall portions formed respectively in the longitudinal-direction two end portions of one of said support plate portions in such a manner that said bent wall portion are bent toward the inner surface side of said one support plate portion, and said pivot shafts are respectively disposed on the outer surfaces of said pair of bent wall portions in such a manner that they are concentric with each other,
• wherein the section area of said one support plate portion is expressed as S, the length of the portion of said one support plate portion that exists between the respective inner surfaces of said pair of bent wall portions is expressed as L, and the section coefficient of said one support plate portion is expressed as Z, a ratio (S×L)/Z is specified in the range of 10-35.