Abstract: The driving pulley has a fully clutched mode of operation where a drivebelt and a driveshaft are coupled together in a torque transmitting engagement and also has an unclutched mode of operation where there is substantially no torque transmitting engagement between the drive belt and the driveshaft. The driving pulley comprises at least one transitional clutch spring that is in a first position when the driving pulley is in the unclutched mode of operation and that is in a second position when the driving pulley is in the fully clutched mode of operation. The at least one transitional clutch spring remains substantially in its second position regardless of the relative axial distance between the sheaves when the driving pulley is in the fully clutched mode of operation. A method of operating a driving pulley is also disclosed. The proposed concept provides a smoother engagement during the transition from the unclutched mode to the fully clutched mode.

Abstract: The driven pulley (10) comprises a first sheave (12) and a second sheave (40) coaxially mounted around a main shaft. The first sheave (12) is fixed with reference to the main shaft while the other sheave (40) is allowed to slide and rotate with reference to the main shaft. The driven pulley (10) is designed with a roller mounting unit (74) facilitating the assembling or the replacement of the rollers (70).

Abstract: The driven pulley is part of a continuously-variable transmission (CVT). The driven pulley comprises two coaxially-disposed sheaves defining between them a belt-receiving groove. It also has at least two axisymmetric ramp surfaces attached to one of the sheaves and at least two axisymmetric followers attached to the other sheave, each ramp surface being engageable by a corresponding one of the followers. At least some of the ramp surfaces are provided on corresponding ramp holders that are independent from the sheaves. A method of modifying the settings of a driven pulley and a method of assembling a driven pulley also disclosed.

Abstract: The driving pulley comprises two centrifugal mechanisms, namely a positive assembly and a negative assembly. Both assemblies comprise a respective set of flyweights subjected to the centrifugal force when the driving pulley rotates. The positive assembly is used as a conventional speed governor that moves one of the two flanges of the driving pulley towards the other in order to increase its winding diameter when the rotation speed increases. The negative assembly is used to apply an opposite force on the positive assembly when the rotation speed is above a threshold value so as to defer the upshift of the CVT to a higher ratio under the action of the positive assembly. This allows to maintain, for instance, a high rotation speed during an intense acceleration and a lower rotation speed when cruising at low vehicle speeds.

Abstract: The double-sided sliding button comprises two spaced-apart sliding button halves configured and disposed with reference to a curved medial axis. Each half has a front side, provided with a contact surface, and a rear side. Both contact surfaces are mutually opposite and both sides of each half intersect the curved medial axis. A bridge member allows to rigidly connect the rear side of the two halves. With this configuration, each sliding button can be easily installed and secured in a clamp attached to a part of the driven pulley. Each double-sided sliding button is capable of working in both directions, thereby reducing the number of individual sliding buttons to be installed by 50%.

Abstract: The driven pulley comprises a first sheave and a second sheave coaxially mounted around a main shaft. The first sheave is fixed with reference to the main shaft while the other is allowed to slide and rotate with reference to the main shaft. The driven pulley is designed so that a portion of the second sheave can enter inside the first sheave. The return spring is also provided inside the driven pulley. This driven pulley can be designed as a reversible driven pulley by adding a second set of ramps and followers. The design of the driven pulley allows it to be constructed in a very compact manner and consequently, with a smaller weight compared to an equivalent conventional driven pulley.

Abstract: The driving pulley (12) is used in a continuously variable transmission (CVT) and comprises two flanges (22,24) around which a drivebelt (20) is partially wound. The first flange (22) is fixed in translation with reference to the drive shaft (16) while the second flange (24) is movable, with reference to the first flange (22), between a distal position and a proximal position. The driving pulley (12) is provided with an arrangement which allows the return force on the second flange (24) to be maximum when the second flange (24) is at the distal position, and minimum when the second flange (24) is at the proximal position. The driving pulley (12) is also capable of being disengaged from the drivebelt (20) at a low rotation speed. This driving pulley (12) is particularly well adapted for use on a scooter.

Abstract: A continuously variable transmission comprising a main shaft (2), a fixed flange (14) and a movable flange (16), a first cam system comprising a cam plate (22) provided with cam surfaces (24), and corresponding cam followers (28), a second cam system also comprising a cam plate (40), provided with cam surfaces (42) and corresponding cam followers (46). During a normal forward rotation of the driven pulley (10), corresponding to a forward motion of the vehicle, the first cam system is automatically disabled and the position of the movable flange (16) is governed by the second cam system. However, under motor-braking conditions, the first cam system takes over the control and the second cam system is disabled. Similarly, the first cam system governs the position of the moveable flange (16) during normal reverse rotation of the driven pulley (10) and the second cam system takes over the control under motor-braking conditions as the vehicle is traveling rearwards.

Abstract: The driven pulley (10) is used in a continuously variable transmission (CVT). It is coaxially mountable around a main shaft (12) and comprises two opposite conical flanges, namely a first flange (14) and a second flange (18), which face each other. An annular cam plate (40) is coaxially connected to the side of the second flange (18) that is opposite the first flange (14). The cam plate (40) comprises at least two inclined first cam surfaces (42) and at least two inclined second cam surfaces (44) having an inverted inclination with reference to the first cam surfaces (42). A first radially-extending support (50) bears a set of first cam followers (54). The first support (50) is at a fixed axial distance from the first flange (14) and each first cam follower (54) is engaged with a respective one of the first cam surfaces (42). Similarly, a second radially-extending support (60) bear a set of second cam followers (64).