A continuously variable transmission includes a first main shaft and a second main shaft and at least one auxiliary shaft, rotatable around a rotation axis and interposed between the first and second main shafts. The auxiliary shaft has two secondary roll surfaces. Each secondary roll surface is shaped as a solid of revolution and is placed in contact with a respective primary roll surface of the first and second main shafts. The primary and secondary roll surfaces are shaped so that straight lines tangential thereto in contact points between the auxiliary shaft and the first and second main shafts pass through two distinct intersection points between the axes of the first and second main shafts.

A continuously variable transmission includes a first main shaft and a second main shaft and at least one auxiliary shaft, rotatable around a rotation axis and interposed between the first and second main shafts. The auxiliary shaft has two secondary roll surfaces. Each secondary roll surface is shaped as a solid of revolution and is placed in contact with a respective primary roll surface of the first and second main shafts. The primary and secondary roll surfaces are shaped so that straight lines tangential thereto in contact points between the auxiliary shaft and the first and second main shafts pass through two distinct intersection points between the axes of the first and second main shafts.

A continuously variable transmission includes an input rotor, an output rotor, a plurality of planetary rollers, a guide member, a movable ring, and an elastic member. The input rotor is arranged to rotate about a main axis at a rotation rate before a speed change. The output rotor is arranged to rotate about the main axis at a rotation rate resulting from the speed change. The planetary rollers are arranged around the main axis, and each planetary roller is capable of rotating about a rotation shaft. The guide member is arranged to restrict positions of both end portions of the rotation shaft. The movable ring is capable of rotating about the main axis between the main axis and the planetary rollers. The movable ring is annular, and is capable of moving in an axial direction. The elastic member is capable of expanding and contracting in the axial direction. Each planetary roller includes a first slanting surface, a second slanting surface, and an annular recessed portion or annular projecting portion. The guide member is arranged to hold the end portions of the rotation shaft at different circumferential positions such that each end portion of the rotation shaft is capable of shifting a position thereof in a radial direction with respect to the main axis. The elastic member is arranged to apply a pressure to the movable ring in the axial direction.

A continuously variable transmission includes an input rotor, an output rotor, a plurality of planetary rollers, a guide member, a movable ring, and an elastic member. The input rotor is arranged to rotate about a main axis at a rotation rate before a speed change. The output rotor is arranged to rotate about the main axis at a rotation rate resulting from the speed change. The planetary rollers are arranged around the main axis, and each planetary roller is capable of rotating about a rotation shaft. The guide member is arranged to restrict positions of both end portions of the rotation shaft. The movable ring is capable of rotating about the main axis between the main axis and the planetary rollers. The movable ring is annular, and is capable of moving in an axial direction. The elastic member is capable of expanding and contracting in the axial direction. Each planetary roller includes a first slanting surface, a second slanting surface, and an annular recessed portion or annular projecting portion. The guide member is arranged to hold the end portions of the rotation shaft at different circumferential positions such that each end portion of the rotation shaft is capable of shifting a position thereof in a radial direction with respect to the main axis. The elastic member is arranged to apply a pressure to the movable ring in the axial direction.

A continuously variable transmission includes a first main shaft and a second main shaft and at least one auxiliary shaft, rotatable around a rotation axis and interposed between the first and second main shafts. The auxiliary shaft has two secondary roll surfaces. Each secondary roll surface is shaped as a solid of revolution and is placed in contact with a respective primary roll surface of the first and second main shafts. The primary and secondary roll surfaces are shaped so that straight lines tangential thereto in contact points between the auxiliary shaft and the first and second main shafts pass through two distinct intersection points between the axes of the first and second main shafts.

A continuously variable transmission includes a first main shaft and a second main shaft and at least one auxiliary shaft, rotatable around a rotation axis and interposed between the first and second main shafts. The auxiliary shaft has two secondary roll surfaces. Each secondary roll surface is shaped as a solid of revolution and is placed in contact with a respective primary roll surface of the first and second main shafts. The primary and secondary roll surfaces are shaped so that straight lines tangential thereto in contact points between the auxiliary shaft and the first and second main shafts pass through two distinct intersection points between the axes of the first and second main shafts.

A continuously variable transmission includes an input rotor, an output rotor, a plurality of planetary rollers, a guide member, a movable ring, and an elastic member. The input rotor is arranged to rotate about a main axis at a rotation rate before a speed change. The output rotor is arranged to rotate about the main axis at a rotation rate resulting from the speed change. The planetary rollers are arranged around the main axis, and each planetary roller is capable of rotating about a rotation shaft. The guide member is arranged to restrict positions of both end portions of the rotation shaft. The movable ring is capable of rotating about the main axis between the main axis and the planetary rollers. The movable ring is annular, and is capable of moving in an axial direction. The elastic member is capable of expanding and contracting in the axial direction. Each planetary roller includes a first slanting surface, a second slanting surface, and an annular recessed portion or annular projecting portion. The guide member is arranged to hold the end portions of the rotation shaft at different circumferential positions such that each end portion of the rotation shaft is capable of shifting a position thereof in a radial direction with respect to the main axis. The elastic member is arranged to apply a pressure to the movable ring in the axial direction.

The invention relates to a method for achieving a continuously variable transmission. A power transmission is realized by a drive and driven members creating at least one point of a contact between each other. Each of members may be at least one roller pressed against an opposite members surfaces with virtual surfaces. The method consists in adjustment of movement directions between the surfaces and the roller defined by a first movement vector of the surface relative to contact point, a second movement vector of the roller and a third movement vector of rolling direction of the roller, a steering angle and a correction angle. The steering angle is varied in accordance with a desired transmission ratio and lateral/thrust load on the roller while respecting the deformability of the contact points.

The invention relates to a method for achieving a continuously variable transmission. A power transmission is realized by a drive and driven members creating at least one point of a contact between each other. Each of members may be at least one roller pressed against an opposite members surfaces with virtual surfaces. The method consists in adjustment of movement directions between the surfaces and the roller defined by a first movement vector of the surface relative to contact point, a second movement vector of the roller and a third movement vector of rolling direction of the roller, a steering angle and a correction angle. The steering angle is varied in accordance with a desired transmission ratio and lateral/thrust load on the roller while respecting the deformability of the contact points.

A continuously variable transmission device including a guiding cover rotating about a first axis, a guided cover rotating about a second axis, a planet gear including a first belt in contact with an inner surface of the guiding cover and a second belt in contact with an inner surface of the guided cover, contact areas between the belts and the inner surfaces of the covers being defined in a single first radial plane relative to the first axis, wherein the planet gear rotates about a third axis contained in the first radial plane, the angular orientation relative to the first axis defining the transmission ratio of the device, and wherein the planet gear pivots about a fourth axis perpendicular to the first radial plane and nonintersecting with the first axis, and pivots about a fifth axis parallel to the first radial plane and perpendicular to the third axis.