The control mode is switched between a first control mode configured to control the speed change pump based on an actual speed ratio being an actual speed ratio of the variator, and a second control mode configured to control the speed change pump based on an actual working pressure being an actual working pressure of the variator. In the first control mode, the actual speed ratio is calculated based on a detected value of a vehicle speed; and the speed change pump is controlled to cause the actual speed ratio to approach the target speed ratio. In the second control mode, the actual working pressure is detected and the speed change pump is controlled to cause the actual working pressure to approach a target working pressure corresponding to the target speed ratio. In a situation or a condition where the detection accuracy of the vehicle speed by the vehicle speed sensor decreases, the control mode is switched from the first control mode to the second control mode.

A continuously variable transmission including a first pulley means, a second pulley means and an elongate, flexible endless transmission element that is passed over both the first pulley means and the second pulley means, wherein the first pulley means include two sheaves which are adjustable in an axial direction of the first rotation axis line, and an adjusting means for moving the two adjustable sheaves toward and away from each other in the axial direction for setting an operative radius of the first pulley means at which the transmission element is passed over the first pulley means, wherein the first pulley means is provided with alignment means for causing the two movable sheaves to jointly move additionally in the axial direction of the first rotation axis under the influence of a force exerted in axial direction on the first pulley means by the transmission element while maintaining the operative radius.

A continuously variable transmission including a first pulley means, a second pulley means and an elongate, flexible endless transmission element that is passed over both the first pulley means and the second pulley means, wherein the first pulley means include two sheaves which are adjustable in an axial direction of the first rotation axis line, and an adjusting means for moving the two adjustable sheaves toward and away from each other in the axial direction for setting an operative radius of the first pulley means at which the transmission element is passed over the first pulley means, wherein the first pulley means is provided with alignment means for causing the two movable sheaves to jointly move additionally in the axial direction of the first rotation axis under the influence of a force exerted in axial direction on the first pulley means by the transmission element while maintaining the operative radius.

A method controls a continuously variable transmission including: an oil pump disposed in an oil passage between a primary oil chamber and a secondary oil chamber to control a flow of oil from the secondary oil chamber to the primary oil chamber; and an oil supply source to supply oil to the secondary oil chamber, and the method includes: calculating a secondary hydraulic-pressure command value based on a required primary hydraulic pressure that is a pressure in the primary oil chamber required to transmit an input torque to an output side; and controlling the oil supply source in accordance with the secondary hydraulic-pressure command value.

A method controls a continuously variable transmission including: an oil pump disposed in an oil passage between a primary oil chamber and a secondary oil chamber to control a flow of oil from the secondary oil chamber to the primary oil chamber; and an oil supply source to supply oil to the secondary oil chamber, and the method includes: calculating a secondary hydraulic-pressure command value based on a required primary hydraulic pressure that is a pressure in the primary oil chamber required to transmit an input torque to an output side; and controlling the oil supply source in accordance with the secondary hydraulic-pressure command value.

A damper apparatus for a belt element of a belt transmission includes a sliding surface, a bearing receptacle, a first rail half and a second rail half. The sliding surface is arranged to contact a strand of the belt element to dampen the belt element. The bearing receptacle is arranged to align the sliding surface with the strand such that the sliding surface defines a strand travel direction, normal to a transversal direction. The first rail half has a first plunge opening with a first hook lid, and the second rail half has a second plunge opening with a second hook lid. The first rail half and the second rail half are interlockingly connected in contact to each other crosswise to the strand travel direction, and the first hook lid is arranged to plunge into the second plunge opening behind the second hook lid in a gripping manner.

A damper apparatus for a belt element of a belt transmission includes a sliding surface, a bearing receptacle, a first rail half and a second rail half. The sliding surface is arranged to contact a strand of the belt element to dampen the belt element. The bearing receptacle is arranged to align the sliding surface with the strand such that the sliding surface defines a strand travel direction, normal to a transversal direction. The first rail half has a first plunge opening with a first hook lid, and the second rail half has a second plunge opening with a second hook lid. The first rail half and the second rail half are interlockingly connected in contact to each other crosswise to the strand travel direction, and the first hook lid is arranged to plunge into the second plunge opening behind the second hook lid in a gripping manner.

A hydraulic control system for a continuously variable transmission (CVT) includes a pressure regulator subsystem, a selection valve in downstream fluid communication with the pressure regulator subsystem, the selection valve configured to control a flow of pressurized oil from the pressure regulator subsystem to a primary pulley circuit and a secondary pulley circuit, the primary pulley circuit in fluid communication with a primary pulley and the secondary pulley circuit in communication with a secondary pulley, and a ratio control pump disposed in fluid communication between the primary pulley circuit and the secondary pulley circuit, wherein rotation of the ratio control pump in a first direction pumps pressurized oil from the secondary pulley circuit to the primary pulley circuit and rotation of the control pump in a second direction pumps pressurized oil from the primary pulley circuit to the secondary pulley circuit to change a ratio of the CVT.

A hydraulic control system for a continuously variable transmission (CVT) includes a pressure regulator subsystem, a selection valve in downstream fluid communication with the pressure regulator subsystem, the selection valve configured to control a flow of pressurized oil from the pressure regulator subsystem to a primary pulley circuit and a secondary pulley circuit, the primary pulley circuit in fluid communication with a primary pulley and the secondary pulley circuit in communication with a secondary pulley, and a ratio control pump disposed in fluid communication between the primary pulley circuit and the secondary pulley circuit, wherein rotation of the ratio control pump in a first direction pumps pressurized oil from the secondary pulley circuit to the primary pulley circuit and rotation of the control pump in a second direction pumps pressurized oil from the primary pulley circuit to the secondary pulley circuit to change a ratio of the CVT.

A snowmobile includes a frame, a tunnel, a seat, an endless track, at least one ski, a handlebar, a cowling defining an engine compartment, an engine, a continuously variable transmission (CVT) operatively connecting the engine to the endless track, and a pulley guard assembly disposed over at least a portion of the CVT. The CVT includes a primary pulley, a secondary pulley, and an endless flexible member operatively connecting the primary pulley to the secondary pulley. The pulley guard assembly is disposed between the CVT and a lateral side of the cowling, and defines an air inlet. The air inlet fluidly communicates with a space defined between the pulley guard assembly and the lateral side. In some implementations, the cowling defines an air inlet. In some implementations, an air duct fluidly connects the air inlet of the cowling to the air inlet of the pulley guard assembly.