Automatic transmission

About: Automatic transmission is a research topic. Over the lifetime, 16385 publications have been published within this topic receiving 104301 citations. The topic is also known as: auto gear shift & self-shifting transmission.

Automatic transmission for a power tool

Abstract: A transmission assembly is powered by an electric motor and includes a transmission having an outer ring gear, a connector moveable relative to the outer ring gear between a first position, in which the connector is rotatable with the transmission in response to torque received from the motor, and a second position, in which the connector and the outer ring gear are non-rotatable, and a control mechanism operable to detect the operating current of the motor and compare the operating current to a threshold current. The control mechanism is operable to move the connector from the first position to the second position in response to the motor operating current exceeding the threshold current.

Mechanical automatic transmission

Abstract: An electro-mechanical automatic transmission system for use in motor vehicles. The automatic transmission comprises a mechanical transmission, gear synchronizer and clutch which have been automated by the addition of electro-mechanical and pneumatic operators and an analog and digital electronic control system. The electronic control system receives operator commands regarding the mode of transmission operation (either automatic or manual) and monitors throttle position, engine speed, transmission countershaft speed, drive shaft (vehicle) speed, and rates of change of these speeds. It also receives information of the present gear ratio and stores data indicating the direction of the last shift. By utilizing this information, the electronic control system selects the optimum transmission gear ratio, effects synchronization of the selected transmission gear elements and controls clutch engagement according to a logic program.

Multispeed automatic transmission for automobile vehicles

Abstract: A multispeed automatic transmission for automobile vehicles having parallel input shaft output shaft includes two parallel gearsets and of constant-mesh gearwheels providing two fixed speed ratios. The second speed ratio is higher than the first speed ratio and in same direction. A first power path using the first fixed speed ratio includes a first control clutch and a second control clutch, and a second power path using the second fixed speed ratio includes a third control clutch. Further, the transmission includes a double planetary gearset, a first control brake and a second control brake. Alternatively, the input shaft and output shaft are in alignment and one of the two speed ratios is a direct drive. The transmission features six forward speeds, a braked neutral and a reverse drive.

Control device for vehicular drive system

Abstract: A control device for a vehicular drive system is disclosed as including reverse drive for suppression means operative to preclude output member, such as an output shaft and drive wheels, of an automatic transmission portion from inputting a reverse drive force to a differential portion. This prevents a power transmitting member from rotating in a direction opposite to a rotational direction of the same with a running position being set. This suppresses a first electric-motor rotation speed, determined with an engine rotation speed and a power transmitting member rotation speed based on the relationship on mutually relative rotation speeds in the differential portion, from increasing to a high level. This results in improved durability of a first electric-motor.

Compact multi-ratio automatic transmission

Abstract: An automatic transmission for motor vehicles comprising three interconnected planetary gear units, two rotating friction clutches and four friction brakes providing six optimized forward gear ratios and a reverse ratio, all assembled into a compact package no larger than the current four-speed automatic transmissions. This invention preferably utilizes two multi-plate rotating clutches and special friction force balanced brake bands that allows self-synchronized ratio shifts without creating any side loading of associated band drums.