Piaggio&c. S.p.a.

Paolo Nesti

Walter Mariotti

Stefano Doveri

Giacomo Freschi

Carlo Magagnini

Matteo Puccioni

A continuously variable transmission device () for a two-wheel, three-wheel or four-wheel motorcycle includes a cam system () operating between a fixed bushing () and a mobile bushing (). The device is configured to obstruct the approach between the active surfaces () or to facilitate the approach of the active surfaces.

Continuously variable transmission device with a device for varying the gear shift curve

A CVT transmission device () comprises a drive pulley () provided with a mobile bushing (), a fixed bushing (), a cam system () comprising at least one driven cam portion () of mobile bushing () and a cam portion () of the fixed bushing (). The mobile bushing () comprises a main wall () annular with respect to the axis of rotation (X), having an inner surface () which delimits a housing compartment () and said driven cam portion () protrudes radially internally from said inner surface (). The drive cam portion () of the fixed bushing () is suitable to penetrate axially in said housing compartment of the mobile bushing ().

Continuously variable transmission device with device for varying the transmission curve

A continuously variable transmission device () for a two-, three- or four-wheel motorcycle comprises a gear shift regulation device provided with a slide () axially slidable and suitable to engage special rollers () to hold them during the gear shift. A mobile bushing () is suitable to influence the slide () to cause its translation from a rearward position to a forward limit position to engage the special rollers ().

Continuously variable transmission device with gear regulation device

A continuously variable transmission device () for a two-wheel, three-wheel or four-wheel motorcycle includes a gear shift regulation device suitable to operate on special rollers () through an adjustable axial action independently of the number of engine revolutions. The device influences the centrifugal movement of the rollers () and thus influences the gear shift.

A continuously variable transmission system for a motorcycle includes a first drive sheave () operated by a transmission half-shaft () and a second driven sheave, connected by a V-belt. The drive sheave () has a first half-sheave () and a second half-sheave () substantially conical, sliding axially aligned, joined in rotation. The first half sheave () is fitted internally with a speed regulator composed of centrifugal masses () which move to cause the axial shift in the direction of extension of the transmission half-shaft (), of the first half-sheave () relative to the corresponding second half-sheave (). A device () for regulating the gear change curve is provided with an electromechanical actuator to cause selective intervention of a determined group of centrifugal masses () to vary, for the same number of revs of the engine, the centrifugal force needed to achieve the axial shift of the first half-sheave ().

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Pisa, Italy

Paolo Nesti