Systems and methods for controlling transmissions and associated vehicles, machines, equipment, etc., are disclosed. In one case, a transmission control system includes a control unit configured to use a sensed vehicle speed and a commanded, target constant input speed to maintain an input speed substantially constant. The system includes one or more maps that associate a speed ratio of a transmission with a vehicle speed. In one embodiment, one such map associates an encoder position with a vehicle speed. Regarding a specific application, an automatic bicycle transmission shifting system is contemplated. An exemplary automatic bicycle includes a control unit, a shift actuator, various sensors, and a user interface. The control unit is configured to cooperate with a logic module and an actuator controller to control the cadence of a rider. In one embodiment, a memory of, or in communication with, the control unit includes one or more constant cadence maps that associate transmission speed ratios with bicycle speeds.

Embodiments are directed to a front end accessory drive (FEAD) and power modulating devices (PMD) which can be used in a FEAD. In one embodiment, a continuously variable transmission (CVT) is coupled directly to a crankshaft of a prime mover, and the CVT is used to regulate the speed and/or torque delivered to an accessory. A compound drive device includes a motor/generator subassembly cooperating with a CVT subassembly to provide a motor functionality with torque multiplication or division, or alternatively, a generator functionality with torque multiplication or division. In some embodiments, a FEAD includes a PMD having a sun shaft configured to couple to a sun of the PMD and to an electric motor component, such as an electrical armature or an electrical field. In one embodiment, the electrical armature the electrical field are placed concentrically and coaxially and configured to rotate relative to one another in opposite directions.

A transmission controller of a toroidal continuously variable transmission includes a gain setting unit that adjusts a gain of closed-loop control for calculating a target value of a roller position in accordance with a change in a rotation speed of a disc in a first rotation speed range and a second rotation speed range higher than the first rotation speed range. The gain setting unit changes, in the first rotation speed range, the gain so that sensitivity of the closed-loop control decreases with an increase in the rotation speed, and changes, in the second rotation speed range, the gain so that a rate of decrease in the sensitivity of the closed-loop control with the increase in the rotation speed is smaller than that in the first rotation speed range.

Components, subassemblies, systems, and/or methods for improving the performance and increasing the life of continuously variable transmissions (CVT). A first stator may be formed with an outer diameter greater than an outer diameter of a second stator. A stator may have radial slots formed to extend farther radially inward than slots on the other stator. The larger outer diameter of a stator or the formation of guide slots on a first stator extending farther radially inward of guide slots on a second stator may prevent egress of a planet axle from a radial slot, increase range of the CVT, allow for larger tolerances to reduce losses, and other advantages, Slots on a timing plate may be formed having a width greater than a width of guide slots formed on either stator to allow the stators to control adjustments while the timing plate avoids runaway axles. The shape, including junction between surfaces on a timing plate or stator may also prevent an axle from egressing. Any one or a combination of these features allow a CVT to be formed smaller and lighter to allow for clearance in smaller environments and for reduced inertia.

A transmission variator includes a first pulley rotatably attached to an intermediate member of a geartrain, and a second pulley rotatably attached to an output member that is rotatably coupled to the driveline. The geartrain includes an input member, a planetary gear set, a first clutch, a second clutch and an intermediate member. The second clutch is a low drag clutch. The input member rotatably couples to the prime mover. A controller includes an instruction set that is executable to activate only the first clutch in response to a request to operate the driveline in a forward direction, and activate only the second clutch in response to a request to operate the driveline in a reverse direction.

A vehicle includes an engine, a continuously variable transmission, and a controller. The controller, responsive to a request to manually shift the continuously variable transmission and the engine being on, operates the continuously variable transmission atone of a predetermined number of discrete ratios such that a speed of the engine changes by at least a predetermined amount.

A transmission controller of a toroidal continuously variable transmission includes a gain setting unit that adjusts a gain of closed-loop control for calculating a target value of a roller position in accordance with a change in a rotation speed of a disc in a first rotation speed range and a second rotation speed range higher than the first rotation speed range. The gain setting unit changes, in the first rotation speed range, the gain so that sensitivity of the closed-loop control decreases with an increase in the rotation speed, and changes, in the second rotation speed range, the gain so that a rate of decrease in the sensitivity of the closed-loop control with the increase in the rotation speed is smaller than that in the first rotation speed range.

A method for controlling a continuously variable transmission including a primary oil chamber, a secondary oil chamber, an oil pump provided in an oil passage between the primary oil chamber and a secondary oil chamber. The method including determining whether a required downshift speed is faster than an allowable value; setting a target piston position of the primary oil chamber; setting a target oil pressure of the primary oil chamber; and increasing priority of a position feedback control based on the target piston position in the setting of the target piston position when it is determined that the downshift speed is slower than the allowable value and increasing priority of a hydraulic feedback control based on the target oil pressure in the setting of the target oil pressure when it is determined that the downshift speed is faster than the allowable value.

In a hydraulic control device, a state determination unit of a control unit determines whether a second pump is in a boosting operation or in a transition state. If the state determination unit has determined that the second pump is in the boosting operation or in the transition state, a valve-opening detection unit determines whether a check valve is opened. If the valve-opening detection unit has determined that the check valve is opened, a controller stops the second pump or decreases the rotation number of the second pump.

In a hydraulic control device, a hydraulic sensor is provided on an intake side of a second pump where first oil is taken in and a line pressure sensor is provided on a discharging side of the second pump where the second oil is discharged. A control unit controls driving of the second pump by controlling a motor on the basis of an output pressure detected by the output pressure sensor or a line pressure detected by the line pressure sensor.