A speed control mechanism for controlling selective engagement of the self-propelled transmission assembly for a walk-behind lawn mower is provided. The speed control mechanism is also configured to control the relative output speed of the transmission assembly. The speed control mechanism includes a speed engagement assembly and a speed adjustment assembly, wherein the speed engagement assembly includes a pair of rotatable levers for causing the transmission assembly to actuate between a disengaged position and an engaged position and the speed adjustment assembly includes a rotatable knob for causing the relative output speed of the transmission assembly to the wheels of the lawn mower to increase or decrease.

A speed control mechanism for controlling selective engagement of the self-propelled transmission assembly for a walk-behind lawn mower is provided. The speed control mechanism is also configured to control the relative output speed of the transmission assembly. The speed control mechanism includes a speed engagement assembly and a speed adjustment assembly, wherein the speed engagement assembly includes a pair of rotatable levers for causing the transmission assembly to actuate between a disengaged position and an engaged position and the speed adjustment assembly includes a rotatable knob for causing the relative output speed of the transmission assembly to the wheels of the lawn mower to increase or decrease.

A centrifugally actuated driving pulley for a continuously variable transmission (CVT) has a movable sheave that is connected to the fixed sheave via a ball spline assembly. Also disclosed is a driving pulley for a CVT having a movable sheave that is connected to the fixed sheave via a ball spline assembly, where at least some of the outer grooves receiving the ball bearings of the ball spline assembly are angularly offset from at least some of the corresponding inner grooves receiving the ball bearings of the ball spline assembly. Also disclosed is a driving pulley for a CVT having a movable sheave that is connected to the fixed sheave via a ball spline assembly, where at least some of the outer and inner grooves receiving the ball bearings of the ball spline assembly have a generally ogival cross-section. A CVT and a vehicle having a CVT are also disclosed.

A hybrid vehicle includes an engine, a motor, and a belt stepless speed changer device having a driving rotary body, a driven rotary body, a first shaft member supporting the driving rotary body with allowing rotation thereof in unison, a second shaft member supporting the driven rotary body with allowing rotation thereof in unison, and an endless belt wound around the driving rotary body and the driven rotary body. The vehicle further includes a transmission case configured to receive the powers from the engine and the motor via the belt stepless speed changer device and a centrifugal clutch incorporated in a power transmission line extending form the engine to the first shaft member. The motor is disposed on the side opposite the engine across the driving rotary body, and the driving power of the motor is inputted to the first shaft member.

A control device includes: a clamping force determination unit that determines a clamping force Fs so that a transmission gear ratio R of a stepless transmission is a target transmission gear ratio; a correction unit that corrects the clamping force Fs determined by the clamping force determination unit, based on an oil temperature TO of a lubricant interposed between each of pulleys and a belt and the transmission gear ratio R; and a clamping force control unit that controls clamping of the pulleys and to be performed with the clamping force Fs corrected by the correction unit.

A driven unit helix assembly for a continuously variable transmission including a roller sleeve, a helix, a spring, and a helix sleeve. The roller sleeve is configured to coupled to a movable sheave and axially translate along a post. A plurality of roller assemblies radially extend from the roller sleeve and travel within roller tracks of the helix, such that the roller sleeve and helix define coaxial components coupled an axial sliding engagement. The spring extends from a proximal end coupled to a proximal portion of the helix to a distal end configured to contact at least a portion of the distal portion of the movable sheave, thereby urging the movable sheave in the distal direction. The helix sleeve extends circumferentially around the helix and is configured to retain a fluid in the helix assembly.

A continuously variable transmission (CVT) clutch is provided that includes a CVT gearing control assembly that is configured to move a movable sheave of the CVT clutch axially on a post independent of movement caused by a reactive assembly of the CVT clutch. A slave cylinder housing of the CVT gearing control assembly forms an oil chamber that includes a plurality of slave push piston cylinders. A slave push piston is received in each slave push piston cylinder in the slave cylinder housing. Each slave push piston is in operational communication with an engaging member that is configured to selectively engage and move the movable sheave. An actuator assembly adjusts pressure to selectively move the slave push pistons.

A self-aligning driven clutch is provided that includes a self-aligning return system. The self-aligning return system includes a driven post sleeve and a driven sleeve biasing member. The driven post sleeve is slidably mounted on a driven post in an axially movable arrangement. The driven sleeve biasing member is positioned to exert a biasing force on the driven post sleeve relative to a driven post to a home belt alignment position. A driven fixed sheave is mounted on the driven post sleeve of the self-aligning return system in an axially fixed arrangement. A driven moveable sheave is slidably mounted on the driven post sleeve of the self-aligning return system in an axially movable arrangement. A driven moveable sheave actuation system moves the driven movable sheave in relation to the driven fixed sheave on the driven post sleeve based on at least a force experienced by the self-aligning driven clutch.

A driven unit helix assembly for a continuously variable transmission including a roller sleeve, a helix, a spring, and a helix sleeve. The roller sleeve is configured to coupled to a movable sheave and axially translate along a post. A plurality of roller assemblies radially extend from the roller sleeve and travel within roller tracks of the helix, such that the roller sleeve and helix define coaxial components coupled an axial sliding engagement. The spring extends from a proximal end coupled to a proximal portion of the helix to a distal end configured to contact at least a portion of the distal portion of the movable sheave, thereby urging the movable sheave in the distal direction. The helix sleeve extends circumferentially around the helix and is configured to retain a fluid in the helix assembly.