An actual gear ratio change amount (Gr) is calculated by subtracting a pre-shift gear ratio (Gb) from an actual gear ratio (Gr). A gear ratio (G) is calculated by multiplying the actual gear ratio change amount (Gr) by a predetermined coefficient (C) and adding the product value to the pre-shift gear ratio (Gb). When the shift is an upshift, the gear ratio (G) is compared with aa target gear shift ratio (Ga), and the greater value is set as a virtual gear ratio (Gv). When the shift is a downshift, then the gear ratio (G) is compared with the target gear ratio (Ga) and the smaller value is set as the virtual gear ratio (Gv). A virtual input shaft rotational speed (Nv) is calculated by first dividing the actual gear ratio (Gr) by the virtual gear ratio (Gv) to obtain a quotient and by dividing the actual input shift rotational speed (Nr) by that quotient. A slip amount (S) is calculated by subtracting the actual input shaft rotational speed (Nr) of the automatic transmission (3) from the engine rotational speed (Ne). Finally, the engine rotational speed for display (Nd) is calculated by adding the slip amount (S) to the virtual input shaft rotational speed (Nv).

Provided is a transmission device monitoring system including: a diagnostic frequency estimation unit that extracts a plurality of diagnostic frequency candidate groups from a frequency region separated by a specific frequency or more using at least current information on a motor, a gear ratio of a transmission device, and the number of stages of the transmission device, and estimates a frequency satisfying a specific relationship from frequencies obtained in the plurality of diagnostic frequency candidate groups as a diagnostic frequency; and an abnormality diagnosis unit that diagnoses abnormality of the transmission device using at least the one diagnostic frequency estimated by the diagnostic frequency estimation unit.

Systems and methods for operating a transmission of a hybrid powertrain that includes a motor/generator are described. The systems and methods may classify transmission degradation in response to an estimated transmission input shaft speed that is determined from transmission output shaft speed. In one example, transmission degradation may be correctable transmission degradation, partial transmission degradation, and continuous transmission degradation.

An actual gear ratio change amount (?Gr) is calculated by subtracting a pre-shift gear ratio (Gb) from an actual gear ratio (Gr). A gear ratio (G) is calculated by multiplying the actual gear ratio change amount (?Gr) by a predetermined coefficient (C) and adding the product value to the pre-shift gear ratio (Gb). When the shift is an upshift, the gear ratio (G) is compared with aa target gear shift ratio (Ga), and the greater value is set as a virtual gear ratio (Gv). When the shift is a downshift, then the gear ratio (G) is compared with the target gear ratio (Ga) and the smaller value is set as the virtual gear ratio (Gv). A virtual input shaft rotational speed (Nv) is calculated by first dividing the actual gear ratio (Gr) by the virtual gear ratio (Gv) to obtain a quotient and by dividing the actual input shift rotational speed (Nr) by that quotient. A slip amount (S) is calculated by subtracting the actual input shaft rotational speed (Nr) of the automatic transmission (3) from the engine rotational speed (Ne). Finally, the engine rotational speed for display (Nd) is calculated by adding the slip amount (S) to the virtual input shaft rotational speed (Nv).

Provided herein is a sun assembly for a continuously variable transmission having a plurality of balls, each having a tiltable axis of rotation, a first traction ring assembly in contact with each ball, a second traction ring assembly in contact with each ball, the sun assembly having a first sun ring and a second sun ring located radially inward of, and in contact with, each ball. The sun assembly is operably coupled to an electromagnetic device. In some embodiments, the electromagnetic device is a bearing configured to provide radial support to the balls. In some embodiments, the electromagnetic device is a motor configured to produce an output power from the sun assembly. In some embodiments the electromagnetic device is a speed sensor. In some embodiments, the electromagnetic device is a selectable torque transmitting device.

A controller is configured to determine a current gear ratio step determined on the basis of gear ratio calculation Rg to be actual gear ratio of revolution Nm of main shaft 3a and revolution Nc of counter shaft 3b as well as gear ratio map for defining gear ratio variable allowance range for each of gear ratio steps. When making a decision of status of the determined current gear ratio step, the controller is configured to make delay timer get started when the gear ratio calculation Rg goes within the gear ratio variable allowance range of next step and halt to make a decision of the current gear ratio step while the delay timer is activated. The controller is also configured to make a decision of the status of the current gear ratio step after a predetermined delayed time Tn*(n=1, 2, . . . ) is elapsed.

A failure judgment device of an automatic transmission includes: a first abnormality judging section configured to judge a power supply fault abnormality or a breaking abnormality of the solenoid, from a selected shift stage and a state of the transmission mechanism, after the detection of the electric abnormality; and a second abnormality judging section configured to judge the power supply abnormality or the breaking abnormality of the solenoid, from the monitor current value when the solenoid valve is switched to an OFF state, after the detection of the electric abnormality, when one of the first abnormality judging section and the second abnormality judging section judges the power supply fault abnormality or the breaking abnormality, the judgement result being outputted.

A control system to control an operation of a power transmission of a work vehicle includes a storage to store data indicating a relationship between a ratio between a rotational speed of a predetermined component on a power transmission path to transmit the rotation of the planetary transmission to wheels and a rotational speed of the internal combustion engine, and switching points at which the transmission gear of the planetary transmission is switched, and a controller to control the hydraulic clutch mechanism to perform switching of the transmission gear. Where the transmission gear is switched when the ratio changes to reach a first value corresponding to a first switching point or after the ratio reaches the first value, the controller controls the hydraulic clutch mechanism so as to start hydraulic fluid charging to perform switching of the transmission gear before the ratio reaches the first value.

Systems and methods for operating a transmission of a hybrid powertrain that includes a motor/generator are described. The systems and methods may classify transmission degradation in response to an estimated transmission input shaft speed that is determined from transmission output shaft speed. In one example, transmission degradation may be correctable transmission degradation, partial transmission degradation, and continuous transmission degradation.

Systems and methods for operating a transmission of a hybrid powertrain that includes a motor/generator are described. The systems and methods may classify transmission degradation in response to an estimated transmission input shaft speed that is determined from transmission output shaft speed. In one example, transmission degradation may be correctable transmission degradation, partial transmission degradation, and continuous transmission degradation.