US 10,253,880 B2 · Continuously variable transmission

Abstract

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable accessory drives (CVAD). In one embodiment, a skew-based control system is adapted to facilitate a change in the ratio of a CVAD. In another embodiment, a skew-based control system includes a skew actuator coupled to a carrier member. In some embodiments, the skew actuator is configured to rotate a carrier member of a CVT. Various inventive traction planet assemblies can be used to facilitate shifting the ratio of a CVT. In some embodiments, the traction planet assemblies include legs configured to cooperate with the carrier members. In some embodiments, a traction planet assembly is operably coupled to the carrier members. Embodiments of a shift cam and traction sun are adapted to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces for a CVT are disclosed.

Claims10

Dependent claims

A method for controlling a continuously variable accessory drive (CVAD) with a continuously variable transmission (CVT) coupled to a prime mover and a load, the CVT having a plurality of traction planets, each traction planet adapted to rotate about a tiltable axis, the method comprising:

a) receiving a desired output speed for the CVT;
b) determining a command signal for a skew actuator, the skew actuator comprising a hydraulic piston coupled to the CVAD, the hydraulic piston operably coupled to a first carrier member of the CVAD, the first carrier member comprising a plurality of radially offset slots formed in the first carrier member and arranged angularly about a longitudinal axis of the CVAD;
c) applying the command signal to the skew actuator, wherein applying the command signal to the skew actuator causes the first carrier member to rotate about the longitudinal axis to apply a skew condition to tilt the axes of the plurality of traction planets, wherein the tilt angle determines an output speed of the CVT;
d) measuring the output speed of the CVT;
e) comparing the measured output speed to the desired output speed;
and
f) repeating step b) through step e) until the measured output speed is substantially equal to the desired output speed.

4 more elements

A continuously variable transmission (CVT) system for use in a continuously variable accessory drive (CVAD), comprising:

an input driver for receiving power from an input shaft coupled to an external source;
a first traction ring coupled to the input driver for receiving power;
a variator assembly coupled to the first traction ring for receiving power from the first traction ring;
a second traction ring coupled to the variator assembly for receiving power from the variator assembly;
a planetary gear assembly coupled to the second traction ring and further coupled to an output shaft;
and
a controller operable to:
a) receive a desired output speed for the CVT;
b) determine a command signal for a skew actuator, the skew actuator comprising a hydraulic piston coupled to the CVAD, the hydraulic piston operably coupled to a first carrier member of the CVAD, the first carrier member comprising a plurality of radially offset slots formed in the first carrier member and arranged angularly about a longitudinal axis of the CVAD;
c) apply the command signal to the skew actuator, wherein applying the command signal to the skew actuator causes the first carrier member to rotate about the longitudinal axis to apply a skew condition to tilt the axes of the plurality of traction planet assemblies, wherein the tilt angle determines an output speed of the CVT;
d) measure the output speed of the CVT;
e) compare the measured output speed to the desired output speed;
and
f) repeat step b) through step e) until the measured output speed is substantially equal to the desired output speed.

11 more elements

Dependencies are inferred from the claim text.

Continuously variable transmission

Life of this patent

Continuously variable transmission

Life of this patent

Abstract

Claims10