Jatco Corporation

Nissan Motor Company Limited

Takuichiro Inoue

Hiroyasu Tanaka

Mamiko Inoue

Ryousuke Nonomura

Seiichiro Takahashi

Jouji Seki

Masahiro Yamamoto

Yoshihisa Kodama

Hideki Oshita

Makoto Komatsu

Hideaki Suzuki

Yuji Okamoto

Kousuke Abe

Hideshi Wakayama

Tetsuya Izumi

Masayuki Miyazono

Fumito Shinohara

Kunihiro Takahashi

Youhei Ishikawa

Takashi Koguchi

Norio Asai

Sho Okutani

Masashi Suwabe

Hiroyuki Suzuki

Masahiro Iriyama

Hiroki Iwasa

Shigeki Shimanaka

Tatsuo Ochiai

Tatsuo Wakahara

Yuzuru Tohta

Takashi Eguchi

Hisao Nobu

Midori Yamaguchi

Kenichi Gotou

Toshiaki Noda

Masato Mori

Tetsuya Shimada

Aki Hayakawa

Koutarou Tagami

Yuuji Nagase

Takeshi Oohori

Takashi Nobukawa

Jongkeun Lim

Satoru Ishii

Kenji Hishida

As a mode switching shift line when a sub-transmission mechanism is switched from a first-speed to a second-speed, a first mode switching shift line, which prioritizes a learning of a hydraulic pressure with which a Low brake starts to slip and a learning of a hydraulic pressure with which a High clutch starts to transmit a torque, or a second mode switching shift line, which is a shift line in a Low side with respect to the first mode switching shift line and prioritizes a fuel efficiency of an engine is selected, and the sub-transmission mechanism is switched from the first-speed to the second-speed on the basis of the selected mode switching shift line.

Control device for continuously variable transmission and control method of the same

Disclosed is a control device for a continuously variable transmission () that has, as forward speed change stages, a first speed change stage () and a second speed change stage (). The control device comprises a coordinated speed change means () that carries out a coordinated speed changing in such a manner that when the speed change stage of an auxiliary transmission mechanism () is about to be changed, a speed change speed of the auxiliary transmission mechanism () is coordinated with a variator () and the variator () is controlled to carry out a speed change in a direction opposite to that of the auxiliary transmission mechanism () while carrying out the speed change operation of the auxiliary transmission mechanism (), and a torque control means () that carries out a torque regulating control during the coordinated speed changing under up-shifting by the coordinated speed change means, the torque regulating control being a control for effecting a torque-up operation to a driving source () after effecting a torque-down operation to the driving source and including a timing through which a starting time point of a drive force gap caused by the coordinated speed changing is advanced and a timing through which an ending time point of the drive force gap is delayed.

Control device for continuously variable transmission

A control device for a continuously variable transmission with an auxiliary transmission includes: a cooperative control section being configured to shift the auxiliary transmission mechanism during the first inertia phase time period, and to shift the variator during the second inertia phase time period, when the cooperative control in which an input torque to the continuously variable transmission is equal to or smaller than a predetermined value in the cooperative control is judged, and being configured to shift the auxiliary transmission mechanism during the first inertia phase time period, and to shift the variator during the first inertia phase time period when the cooperative control in which the input torque to the continuously variable transmission is greater than the predetermined value is judged.

Control device for continuously variable transmission equipped with auxiliary transmission

A transmission controller increases hydraulic pressure supplied to a secondary pulley and decreases hydraulic pressure supplied to a primary pulley to shift a variator to a mechanical Low speed ratio when the hydraulic pressure supplied to the primary pulley and the secondary pulley vibrates. The transmission controller shifts the variator from the mechanical Low speed ratio to a High side when a sub-transmission mechanism is downshifted during controlling a speed ratio of the variator at the mechanical Low speed ratio.

Continuously variable transmission and method for controlling the same

An automatic transmission control device implements a downshift by disengagement of a clutch that is engaged in a gear position before the downshift. It is determined whether an engine state is in a predetermined region in which a change of an engine torque per a change of an accelerator pedal opening is smaller than that in another region, and the engine torque is within a predetermined range, and an engine rotational speed is within a predetermined range. It is determined whether an operating state is in a predetermined state of accelerator operation in which the accelerator pedal opening is larger than a predetermined value, and an accelerator pedal opening change rate has an absolute value smaller than a predetermined value. The downshift is inhibited in response to determination that the engine state is in the predetermined region and the operating state is in the predetermined state of accelerator operation.

Automatic transmission control device

An engine control device for a vehicle including a power train where a continuously variable transmission is coupled to an engine, includes engine torque control means configured to control the engine so as to obtain an basic engine torque corresponding to an operating state of the vehicle, and command means configured to command engine torque control means to increase an engine torque from the basic engine torque during a gear shifting from a first speed stage to a second speed stage. The continuously variable transmission includes a continuously variable transmission mechanism, an auxiliary transmission mechanism that includes at least a first engagement portion and a second engagement portion to achieve the gear shifting from the first speed stage to the second speed stage, and shift control means configured to set a target value of a transmission gear ratio of the entire continuously variable transmission mechanism and the auxiliary transmission mechanism based on the operating state of the vehicle to control the continuously variable transmission mechanism such that the target value is achieved.

Engine control device for vehicle and engine control method for vehicle

A control device for a continuously variable transmission with an auxiliary transmission includes: a cooperative control section; and a depression shift control section, wherein when an actual transmission gear ratio of the variator at the judgment of the depression shift control is higher than a first transmission gear ratio set as a lowest value of a control of the transmission gear ratio, the depression shift control section configured to downshift the variator, and to set a target transmission gear ratio at the shift of the variator to a second transmission gear ratio which is a restriction value that is higher than the first transmission gear ratio.

A transmission controller increases hydraulic pressure supplied to a secondary pulley and decreases hydraulic pressure supplied to a primary pulley to shift a variator to a mechanical Low speed ratio during the hydraulic pressure supplied to the primary pulley and the secondary pulley vibrates. The mechanical Low speed ratio is a speed ratio where a groove width of the primary pulley has a maximum value possible to be employed in structure of the primary pulley.

A transmission controller executes synchronization shift of shifting a variator in a direction opposite to a speed ratio change direction of a sub transmission mechanism when shifting a sub transmission mechanism. When a gear position of the sub transmission mechanism is at the second gear position and an output increase request of a power source is made, the transmission controller prohibits the synchronization shift and shifts only the sub transmission mechanism from a second gear position to a first gear position.

Continuously variable transmission and method of controlling the same

A transmission controller determines whether or not to downshift a sub-transmission mechanism based on an opening and an opening speed of an accelerator pedal and a torque change rate of an engine, and downshifts the sub-transmission mechanism when a determination is made to downshift the sub-transmission mechanism.

Continuously variable transmission and control method therefor

A transmission controller determines whether or not an input rotation speed of a sub-transmission mechanism is stagnant and executes a feedback control by adding a rotation speed change rate feedback correction amount caused by a difference between a target input rotation speed change rate and an actual input rotation speed change rate of the sub-transmission mechanism to a rotation speed feedback correction amount if the input rotation speed is determined to be stagnant.

The automatic transmission includes a first friction engagement element which is engaged when a first gear position is realized and disengaged when a second gear position is realized, a second friction engagement element which is engaged when the second gear position is realized and disengaged when the first gear position is realized, and a controller. The controller causes the second friction engagement element to slip by decreasing an instructional pressure for the second friction engagement element while running in the second gear position, and learns an engagement start pressure of the first friction engagement element based on a change in a differential rotation of the second friction engagement element, or in a parameter that changes in accordance with the differential rotation, at a time when an instructional pressure for the first friction engagement element is increased during the slip.

Automatic transmission and method for controlling same

When a through speed ratio, which is an overall speed ratio of a variator and a subtransmission mechanism, varies from a larger speed ratio than a mode switch speed ratio to a smaller speed ratio than the mode switch speed ratio, a gear position of the subtransmission mechanism is changed from a first gear position to a second gear position. The mode switch speed ratio is set at a through speed ratio obtained when the speed ratio of the variator is a Highest speed ratio and the gear position of the subtransmission mechanism is the first gear position.

Continuously variable transmission and control method thereof

A control device for a vehicle continuously variable transmission comprises a shift control means for controlling either of or both the speed ratio at the continuously variable transmission mechanism and the gear position at the subtransmission mechanism so as to adjust an overall speed ratio to a final speed ratio and a torque capacity control means for controlling the torque capacity at a disengagement-side frictional engagement element in the subtransmission mechanism so as to sustain a torque capacity value substantially equal to zero in an inertia phase occurring during a process of adjusting the gear position at the subtransmission mechanism from the first gear position to the second gear position when a negative torque is input to the vehicle continuously variable transmission.

Control of and control method for vehicle continuously variable transmission

A control device for a vehicle continuously variable transmissionincludes: final speed ratio setting means for setting an overall speed ratio of the continuously variable transmission mechanismand the subtransmission mechanismto be reached on the basis of an operating condition of the vehicle as a final speed ratio; shift control means for controlling the continuously variable transmission mechanismand the subtransmission mechanismsuch that the overall speed ratio aligns with the final speed ratio at a predetermined transient response; stagnation determining means for determining whether or not a stagnation period in which the overall speed ratio stops varying will occur during an upshift; and reduction control means for shortening a time required to advance to an inertia phase from a start of a shift in the subtransmission mechanismfollowing a determination that the stagnation period will occur.

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Fujisawa, Japan

Takuichiro Inoue