Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing “empty” cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

The system includes: a driver; a rotating load configured to be driven into rotation by the driver; a controller, for controllably changing a rotation speed of the load; and a variable speed transmission, arranged between the driver and the load. The variable speed transmission includes a speed summing gear arrangement with a first input shaft, a second input shaft and an output shaft. The output shaft is drivingly coupled to the rotating load. The first input shaft is drivingly coupled to the driver. A continuous variable transmission device is mechanically coupled to the driver and to the second input shaft of the speed summing gear arrangement. The continuous variable transmission device is functionally coupled to the controller.

A continuously variable transmission (1) having the cams (9, 10, 11, 12) that are not circular as usual, but have the form of a spiral. The outer contours (15, 16, 7, 18) of the two cams (9, 10, 11, 12) are each situated in a plane which is perpendicular to the direction of rotation of the respective cams (9, 10, 11, 12).

An electronic controller for a variable ratio transmission and an electronically controllable variable ratio transmission including a variator or other CVT are described herein. The electronic controller can be configured to receive input signals indicative of parameters associated with an engine coupled to the transmission. The electronic controller can also receive one or more control inputs. The electronic controller can determine an active range and an active variator mode based on the input signals and control inputs. The electronic controller can control a final drive ratio of the variable ratio transmission by controlling one or more electronic solenoids that control the ratios of one or more portions of the variable ratio transmission.

A transmission system for a vehicle having a belt drive transmission. The belt drive has an adjustable input:output ratio, where the output of the belt drive is provided as a first input to a differential coupling. A further rotating connection is provided as a second input to the differential coupling, so that the output of the differential coupling is arranged as the output of the transmission system. Accordingly, the transmission output is based on the aggregate sum of the rotation of the first and second inputs to the differential coupling, wherein adjustment of the input:output ratio of the belt drive allows for a continuously variable transmission system.

A powertrain for a work vehicle includes an engine, a continuously variable power source (CVP), an output shaft, and a transmission. The transmission operably connects the engine and the CVP to the output shaft. The transmission is configured to provide selection between a plurality of transmission modes in which the transmission transmits power from at least one of the engine and the CVP to the output shaft. The transmission includes an input assembly defining an input axis, a variator assembly defining a variator axis, a countershaft assembly defining a countershaft axis, and an output assembly defining an output axis. The input assembly, the variator assembly, the countershaft assembly, and the output assembly are the same in different orientations. A vertical drop distance from the input axis to the output axis varies between the different ones of the plurality of orientations.

A drive train includes a first gear set including a sun gear, a ring gear and planetary gears coupling the sun gear to the ring gear, a second gear set including a sun gear, a ring gear and planetary gears coupling the sun gear to the ring gear, a first motor/generator coupled to the first gear set, a second motor/generator coupled to the second gear set, and at least one of (a) a first clutch that selectively engages the second motor/generator with the first gear set and (b) a second clutch that selectively engages the ring gear of the second gear set with the planetary gear carrier of at least one of the first gear set and the second gear set. The planetary gears of both sets are rotatably supported by respective planetary gear carriers.

A continuous speed variation device includes a input friction disc, a output friction disc, and at least three idle oscillating friction roller members. The input and output friction discs have a friction surface of toroidal shape and the idle oscillating roller members have a friction surface shaped in the form of a spherical dome.

Technologies relating to two channel transmissions are disclosed. A two channel transmission may comprise a differential or epicyclic gear train disposed inside a case, with input/output shafts extending out of case. A speed variator may link inputs and outputs of the differential or epicyclic gear train. The speed variator may comprise, inter alia, a continuously variable transmission (CVT) and a speed range gear. The CVT may link to an input/output shaft outside the case, and the speed range gear may link to an input/output shaft or carrier gear inside the case. In high-stability embodiments, the speed variator may be replaced by a belt or a set of gears.

Split power hydro-mechanical transmission includes an input shaft and an output shaft, a torque converter and a planetary gear set, wherein the input shaft is connected to the turbine rotor and the ring gear or the sun gear, the pump rotor is connected to the sun gear or the ring gear, and the output shaft is connected to the planet carrier. This arrangement introduces strong positive feedback between the pump rotor and the turbine rotor, which results in large maximum torque ratio and large rate of growth of torque ratio, as well as large range of (naturally automatic) torque ratio variation.