Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT). In one embodiment, a main axle is adapted to receive a shift rod that cooperates with a shift rod nut to actuate a ratio change in a CVT. In another embodiment, an axial force generating mechanism can include a torsion spring, a traction ring adapted to receive the torsion spring, and a roller cage retainer configured to cooperate with the traction ring to house the torsion spring. Various inventive idler-and-shift-cam assemblies can be used to facilitate shifting the ratio of a CVT. Embodiments of a hub shell and a hub cover are adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces and braking features for a CVT are disclosed.

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT). In one embodiment, a main axle is adapted to receive a shift rod that cooperates with a shift rod nut to actuate a ratio change in a CVT. In another embodiment, an axial force generating mechanism can include a torsion spring, a traction ring adapted to receive the torsion spring, and a roller cage retainer configured to cooperate with the traction ring to house the torsion spring. Various inventive idler-and-shift-cam assemblies can be used to facilitate shifting the ratio of a CVT. Embodiments of a hub shell and a hub cover are adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces and braking features for a CVT are disclosed.

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT). In one embodiment, a main axle is adapted to receive a shift rod that cooperates with a shift rod nut to actuate a ratio change in a CVT. In another embodiment, an axial force generating mechanism can include a torsion spring, a traction ring adapted to receive the torsion spring, and a roller cage retainer configured to cooperate with the traction ring to house the torsion spring. Various inventive idler-and-shift-cam assemblies can be used to facilitate shifting the ratio of a CVT. Embodiments of a hub shell and a hub cover are adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces and braking features for a CVT are disclosed.

Continuously variable transmissions (CVTs) having a plurality of balls, each ball having a bore through which a ball axle passes, are provided. In some aspects, the CVTs include first and second rings on either side and in contact with the plurality of balls, and an idler assembly including an idler having a non-uniform outer diameter. The profile of the idler ensures lubricant flows to a largest diameter of the non-uniform outer diameter, and lubricant sprays off the largest diameter to lubricate one or more components of the CVT. A lubrication system may include a scraper configured to remove lubricant that accumulates in an interior of the CVT.

A gear and methods for mating the gear to at least on further gear. The gear, for example an idler gear, comprises a gear ring rotationally mounted around a gear hub, the gear hub comprising an axial gear hub opening, wherein the gear comprises a further inner hub rotationally engaging the gear hub, the further inner hub being provided in the gear hub opening, the further inner hub being provided for predeterminedly translating the center of rotation of the gear ring by moving the gear ring and the gear hub with respect to the center of rotation of at least one further gear from a first predetermined position in which the gear mates with the at least one further gear with substantially no backlash to a second predetermined position in which the gear mates with the at least one further gear with a predetermined backlash.

Worm wheel construction that is able to sufficiently increase the strength of the connecting portion between a hub 11a and a gear portion 12a, and to maintain sufficient durability even when applied to an electric power steering apparatus that applies a large auxiliary torque, is achieved. A synthetic resin gear portion 12a is molded and formed in the end portion on the outer-diameter side of a metal hub 11a. A first annular concave portion 15 is provided on one surface side in the axial direction of the hub 11a, and a second annular concave portion 22 is provided on the other surface side in the axial direction thereof. Part of the synthetic resin of the gear portion 12a is fed into the portions near the outer diameter of the first annular concave portion 15 and the second annular concave portion 22 to form a first restraining portion 18 and a second restraining portion 23. These restraining portions 18, 23 tightly hold the end portion on the outer-diameter side of the hub 11a, and improve the strength and rigidity of the connecting portion between the hub 11a and the gear portion 12a.

A core of a worm wheel has an axial end surface formed with a first annular recess, another axial end surface formed with a second annular recess, and a third annular recess formed in a radially outer region of the first annular recess. A rim portion has a first inner circumferential portion fixed to the first annular recess, a second inner circumferential portion fixed to the second annular recess, and a protrusion engaged with the third annular recess.

A core of a worm wheel has an axial end surface formed with a first annular recess nad and another axial end surface formed with a second annular recess. An outer circumferential wall surface of a radially outer region of the second annular recess has a tapered surface extending from a bottom surface of the second annular recess to form an obtuse angle relative to the bottom surface, and a third annular recess formed radially outside the tapered surface. A cross-section of the third annular recess is a right-angled triangle having, as two sides, a surface parallel to the bottom surface of the second annular recess and a surface perpendicular to the bottom surface of the second annular recess. A rim portion has a first inner circumferential portion fixed to the first annular recess and a second inner circumferential portion fixed to the second annular recess.

A core of a worm wheel has an axial end surface formed with a first annular recess and another axial end surface formed with a second annular recess. A rim portion has a first inner circumferential portion fixed to the first annular recess and a second inner circumferential portion fixed to the second annular recess. An outer circumferential wall surface of the second annular recess extends from a bottom surface of the second annular recess so as to be perpendicular to the bottom surface. A depth of the second annular recess is at least 0.1 mm but not deeper than half of a gate thickness.