Gm Global Technolgoy Operations, Inc.

Jesse B Bradley

John E Marano

Zhen J Zhang

Joseph Brian Burtch

Bret M Olson

Vijay A Neelakantan

Kurt J Mitts

Ajit Singh Grewal

Jing Zhou

A method of controlling a variator that requires clamping pressure between a first component and a second component to transfer torque therebetween, such as a continuously variable transmission, includes calculating a theoretical clamping pressure, and multiplying the theoretical clamping pressure by a multiplier to define a commanded clamping pressure. The multiplier includes a value that is variable between a minimum multiplier value and a maximum multiplier value. The value of the multiplier is based on current operating conditions of the variator. The commanded clamping pressure is applied to the first component and the second component to generate friction and transfer torque between the first component and the second component.

Method of controlling a variator

A transmission for a motor vehicle with an engine includes a transmission housing and a dual clutch assembly with a clutch housing connectable to an engine output member. The clutch housing is rotationally supported within the transmission housing. The selective engagement of the dual clutch assembly interconnects the dual clutch housing with at least one of a first input member and a second input member. The transmission also includes a plurality of gear sets associated with various forward and reverse gear ratios, a controller implemented with an algorithm that provides a lock-up profile for the dual clutch assembly, and a plurality of synchronizer assemblies that couple at least one of the gear sets with at least one of a first countershaft and a second countershaft. The selective engagement of at least one of the synchronizer assemblies establishes at least one of the forward speed ratios.

Dual clutch transmission

A vehicle includes an engine, drive wheels, a continuously variable transmission (CVT), and a controller. The CVT includes an input member connected to the engine, an output member delivering output torque to the wheels, and a variator assembly connecting the input and output members. The controller determines, via a method, an input and output speed of the variator assembly, converts the output speed to an equivalent input speed using a calibrated variator speed ratio, and calculates a gross slip of the variator assembly using the input and equivalent input speeds. A gross slip flag is set only when the gross slip exceeds a calibrated slip value for a predetermined duration. A CVT assembly includes the controller, input and output members, and variator assembly. The variator assembly may include drive and driven pulleys, a drive mechanism connecting the pulleys, and an actuator applying a clamping force to one of the pulleys.

Gross slip-based control of a variator assembly

The present invention provides a system for controlling a vehicle comprising a prime mover, a first sensor, a transmission, a second sensor, and a transmission controller. The first sensor outputs a first signal that indicates a speed of an input shaft of the transmission and the second sensor outputs a second signal that indicates a speed of the prime mover. The transmission controller includes control logics that control the transmission using the first signal, perform a diagnostic check on the first sensor, determining whether the diagnostic check of the second control logic indicates that the first sensor meets a predefined performance characteristic, instruct the transmission controller to use the second signal of the second sensor to control the transmission if the third control logic indicates that the first sensor does not meet the predefined performance characteristic, and control the transmission using the second signal of the second sensor.

System and method for controlling a transmission

A debris sensor for a motor vehicle transmission includes a permanent magnet disposed on the inside bottom of the transmission pan to attract and retain magnetically attracted debris such as filings and particulates and a magnetic sensor such as a Hall effect sensor adjacent the permanent magnet. The magnetic sensor monitors, over time, the magnetic field of the debris collecting magnet. The output of the magnetic sensor is provided to a transmission control module (TCM) or similar electronic control or monitoring device. The output of the sensor is monitored and when the output changes sufficiently, relative to experimental or empirical data, a signal or alarm code is generated or stored relating to the possible need for transmission service. Alternatively, data from the sensor may be read at any time to infer the state of the transmission, the quantity of material on the magnet, a possible service issue based upon the quantity of material on the magnet and the vehicle mileage and the remaining service life of the magnet, for example.

Transmission debris sensor

A shift mechanism for a dual clutch transmission employs a rotating barrel cam having at least three tracks which are engaged by and translate at least three associated cam followers. The cam followers extend from shift fork bodies which slide on rails and include shift forks which bi-directionally translate at least three synchronizer clutches which engage at least five forward gears or speeds and reverse. A single electric motor and gear train drive the barrel cam.

Barrel cam shift mechanism

A self-adjusting twin or dual dry clutch assembly for a dual clutch transmission includes a single actuator. The clutch assembly includes one center and two outer clutch drive plates or discs which independently engage a pair of interleaved driven clutch plates or discs which are coupled to and drive a respective pair of transmission countershafts or layshafts. The single actuator translates an internal clutch carrier which acts upon the outer clutch plates through respective pluralities of linear one way clutches. Self-adjustment of the dual clutch assembly is achieved by additional linear one way clutches acting through pairs of spring biased control rods.

Growing community of inventors

Royal Oak, MI, United States of America

Jesse B Bradley