Jatco Corporation

Nissan Motor Company Limited

Shinya Mochiyama

Fumitaka Nagashima

Takateru Kawaguchi

Hideharu Yamamoto

Yoshihide Shinso

Hiroki Kawakami

Hisashi Saito

Atsushi Maeda

Satoshi Ozawa

A friction engagement element (CLx) is provided radially outside of a peripheral wall portion () of a clutch drum () and configured to be engaged by a piston (). A piston () is provided radially inside of the peripheral wall portion () and configured to engage and a friction engagement element (CLz). A first peripheral wall portion () of the peripheral wall portion () includes through-holes () communicating a radially inside of the first peripheral wall portion () with a radially outside thereof. A through-hole () is provided radially inside of the piston (). The piston () includes a communication passage () radially passing through the piston () and communicating the through-hole () with the through-holes () such that lubricating oil is supplied through the communication passage () and the through-holes () to the radially outside of the clutch drum () when the piston () is in an initial position.

Lubricating structure for friction engagement element of automatic transmission

In line pressure control apparatus and method for a vehicle, a line pressure controller outputs a line pressure command to reduce an indicated pressure toward a required indicated pressure by which a required pressure can be secured and which is lower than an initial stage indicated pressure from the initial stage indicated pressure preset to be higher than the required pressure, while a state of each of an electrically driven oil pump (sub-O/P) and a mechanical oil pump (M-O/P) enters a first region (a) and outputs the line pressure command to hold the indicated pressure at a time point at which the first region is ended, while the state enters a second region (b), when a hydraulic pressure source is transitioned from the electrically driven oil pump to the mechanical oil pump.

Line pressure control apparatus and method for vehicle

In control apparatus and method for a hybrid vehicle, a line pressure control valve disposed at a downstream side of each of mechanical oil pump (M-O/P) and electrically driven oil pump (S-O/P) to decrease a supplied hydraulic pressure from at least one of the mechanical oil pump and the electrically driven oil pump by opening drain ports thereof in accordance with a control valve command value is provided, the control valve command value is set by adding a predetermined additive correction quantity to a required line pressure set in accordance with operating states of a hydraulic pressure clutch (CL) and a transmission and the drain ports of the line pressure control valve are controlled to a closure side, during an actuation of the electrically driven oil pump.

Control apparatus and method for hybrid vehicle

The hydraulic control apparatus calculates a target engagement hydraulic pressure of a frictional engagement element, controls the frictional engagement element so that a revolution speed at a driving source side of the frictional engagement element is higher than a revolution speed at a driving wheel side of the frictional engagement element, outputs a command current to a solenoid valve on the basis of a map having a relationship between the target engagement hydraulic pressure and the command current, and decreases the engagement hydraulic pressure when a vehicle speed is equal to or less than a predetermined vehicle speed at which the vehicle is judged to be vehicle stop during execution of the slip control. Further, the hydraulic control apparatus corrects the map so that a variation of the command current with respect to a variation of the target engagement hydraulic pressure is small when decreasing the engagement hydraulic pressure.

Hydraulic control apparatus for vehicle

In an automatic transmission of this invention, a determination as to whether or not a failure has occurred in a friction element is made repeatedly while a vehicle is traveling, and control to specify the failed friction element is begun when a vehicle speed falls to or below a predetermined value for the first time following detection of the failure in the friction element (S, S). When the failed friction element has been specified (S, S, S, S, S, S, S), usable gear positions are determined on the basis of the specified friction element, whereupon shift control is performed using only the usable gear positions (S, S, S, S, S, S, S, S).

Automatic transmission and control method thereof

An automatic transmission includes a planetary gear mechanism, an engagement element group including a particular engagement element having first and second pressure chambers, a pressure control valve to regulate the fluid pressure for the particular engagement element, and a selector valve arranged to connect the second pressure chamber with the pressure control valve at a first valve position, and to disconnect the second pressure chamber from the pressure control valve at a second valve position. A shift control section is configured to command a shift operation from a first gear position, to a second gear position, by controlling the selector valve to the second valve position and to supply the fluid pressure to the first pressure chamber, and to judge the selector valve to be in an abnormal state, in accordance with a parameter in the shift operation.

Automatic transmission

An automatic transmission includes a plurality of planetary gears disposed between an input shaft and an output shaft and having a plurality of rotational elements. A plurality of frictional elements are selectively engaged and released for controlling rotations and connections of the plurality of rotational elements in accordance with instructions so as to realize a plurality of gear positions. A rotational speed detecting section detects a rotational speed of a predetermined one of the plurality of rotational elements other than the input shaft and the output shaft. A frictional element release section releases all of the plurality of frictional elements when it is judged that the rotational speed of the predetermined one of the plurality of rotational elements is higher than a predetermined rotational speed.

Automatic transmission and method of preventing over-revolution of the same

In a planetary gear type stepped automatic transmission, a gear shift control to shift a gear shift stage between a first gear shift stage and a second gear shift stage is performed by a first shift control section by referring to a first gear shift control data used when the gear shift stage is switched between the first gear shift stage and the second gear shift stage, an abnormality state due to a failure of at least one of a first frictional engaging element and a second frictional engaging element is detected, and an abnormality state gear shift control is performed to shift the gear shift stage between a third gear shift stage (for example, first speed) and a fourth gear shift stage (for example, 2.5 speed) by the first shift control section, while forcefully releasing the first frictional engaging element, when detecting the abnormality state.

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Fuji, Japan

Shinya Mochiyama