Abstract: The present invention relates to relates to an improvement of a dividing wall for a primary pulley in a belt-type continuously variable transmission. It is an object of the present invention to obtain a desired strength characteristic without performing a soft nitriding treatment and achieve cost reduction. A hydraulic pressure chamber is formed between the dividing wall and the movable sheave, and the dividing wall comprises a small-diameter annular disc portion 32 extended from the central cylinder portion 30, which is attached to a rotational shaft, in a radial direction. In the small-diameter annular disc portion 32, a connecting portion which is connected to an intermediate body portion 34 is a bent portion 38 which is bent at substantially 90 [deg].

Abstract: The present invention relates to relates to an improvement of a dividing wall for a primary pulley in a belt-type continuously variable transmission. It is an object of the present invention to obtain a desired strength characteristic without performing a soft nitriding treatment and achieve cost reduction. A hydraulic pressure chamber is formed between the dividing wall and the movable sheave, and the dividing wall comprises a small-diameter annular disc portion 32 extended from the central cylinder portion 30, which is attached to a rotational shaft, in a radial direction. In the small-diameter annular disc portion 32, a connecting portion which is connected to an intermediate body portion 34 is a bent portion 38 which is bent at substantially 90 [deg].

Abstract: A plunger member 3 used for a belt type continuously variable transmission is configured by cold press molding a blank material 32 according to deep-drawing molding, and closed forging, compression molding or a combined molding thereof, where during the cold press molding, a thickness of a bent corner portion 3f, which at least makes a sleeve portion 3c and a step-like formed portion (spring seating portion) 3d continuous to each other, is configured to be increased by 30% or more relative to a thickness of the blank material 32, and then a hardened surface layer 3B is configured to be formed on both of the entire front and back sides of the plunger member by performing a soft nitriding treatment.