Patent ID: 9222579
Filing Date: 2015-12-29
Classification: F16H

Abstract:
1. A belt-drive continuously variable transmission comprising: a primary pulley comprising a primary fixed sheave having a primary fixed sheave shaft and a primary moveable sheave having a primary moveable sheave sleeve, the primary moveable sheave sleeve being fitted onto the primary fixed sheave shaft and slidably moveable relative to the primary fixed sheave shaft in an axial direction of the primary pulley, a secondary pulley comprising a secondary fixed sheave having a secondary fixed sheave shaft and a secondary moveable sheave having a secondary moveable sheave sleeve, the secondary moveable sheave sleeve being fitted onto the secondary fixed sheave shaft and slidably moveable relative to the secondary fixed sheave shaft in an axial direction of the secondary pulley, a belt wound on the primary pulley and the secondary pulley to transmit a driving force from a drive source to the primary pulley and the secondary pulley; a first fixed side axial groove extending on an outer circumferential surface of the primary fixed sheave shaft in the axial direction of the primary pulley; a first moveable side axial groove extending on an inner circumferential surface of the primary moveable sheave sleeve in the axial direction of the primary pulley so as to be opposed to the first fixed side axial groove; a first intervening member disposed between the first fixed side axial groove and the first moveable side axial groove, the first intervening member serving to reduce slide resistance that is caused when the primary moveable sheave sleeve makes an axial slide motion in a transmission range between a third transmission ratio and a second transmission ratio, a first axial tapered groove formed as a part of at least one of the first fixed side axial groove and the first moveable side axial groove which is disposed corresponding to a first transmission ratio range, the first axial tapered groove being formed such that a depth defined between the first fixed side axial groove and the first moveable side axial groove is gradually reduced toward a side of a first transmission ratio which is higher than the second transmission ratio, and a first intervening member displacement limiting member arranged to limit an amount of displacement of the first intervening member relative to the primary fixed sheave shaft or the primary moveable sheave sleeve along the first fixed side axial groove or the first moveable side axial groove, wherein when the primary moveable sheave sleeve is moved toward a lock position in which the primary moveable sheave sleeve is to be locked, the lock position corresponding to the first transmission ratio, the first intervening member displacement limiting member is configured to input an engagement force produced by a hydraulic thrust acting on the primary moveable sheave to the first intervening member, the engaging force being exerted on the first intervening member in a same direction as the hydraulic thrust so as to urge the first intervening member into the first axial tapered groove, wherein the first intervening member is urged into the first axial tapered groove so as to be fitted therein, wherein when the primary moveable sheave sleeve is moved apart from the lock position thereof, the first intervening member displacement limiting member is configured to input a disengagement force produced by a belt reaction force acting on the primary moveable sheave to the first intervening member, and wherein the first intervening member is arranged to move relative to the first intervening member displacement limiting member.