Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Yaskawa Denki

Kenji Matsuo

Hiroki Kondo

Daisuke Inoue

Mitsuhiro Fukao

Katsumi Kono

Atsushi Ayabe

Hiroji Taniguchi

Hideki Yasue

Akira Hino

Tadashi Tamura

Yuji Hattori

Motonori Kimura

Michio Yoshida

Kazuya Sakamoto

Hirofumi Nakada

Akihide Ito

Yoshiaki Yamamoto

Ryoji Habuchi

Shuhei Ishikawa

Hiromitsu Nitani

Kyohei Suzumura

Hiroshi Morioka

Kunio Hattori

Hideaki Bunazawa

Hiroya Tanaka

Hiroki Takeda

Yusuke Ohgata

Makoto Sawada

Takuro Shimazu

Yoshisuke Kametani

Takashi Seo

Akihide Itoh

Satoshi Kamijo

Yukihiko Ideshio

Kunio Morisawa

Zenichiro Mashiki

Yuji Inoue

Takashi Inoue

Shingo Eto

Koichi Tanaka

Masami Sugaya

Isao Takagi

Yusuke Ogata

Shuji Moriyama

Tomokazu Inagawa

Hirofumi Kubota

Nobuaki Takahashi

Kazuaki Nakamura

Yousuke Michikoshi

Kozo Yamamoto

Masato Terashima

Syoichi Sayo

Toshio Suzuki

Yuji Iwatsuru

Naofumi Nishida

Mitsuhiro Toyoda

Ryuji Chida

Kazuya Ishiizumi

Satoshi Taninaka

Saburo Ono

Shinichi Matani

A diagnostic apparatus for a vehicle provided with a continuously-variable transmission including a primary pulley, a secondary pulley and a belt looped over the primary and secondary pulleys, such that each of the primary and secondary pulleys includes a hydraulic actuator to which a working fluid is to be supplied. The diagnostic apparatus is configured, in event of occurrence of slippage of the belt on at least one of the primary and secondary pulleys, to infer a factor causing the slippage of the belt, based on at least one of a hydraulic pressure of the working fluid supplied to the hydraulic actuator of the primary pulley and a hydraulic pressure of the working fluid supplied to the hydraulic actuator of the secondary pulley, upon the occurrence of the slippage of the belt.

Diagnostic apparatus for vehicle

A belt-slippage diagnostic apparatus for a continuously-variable transmission that includes a primary pulley, a secondary pulley and a belt looped over the primary and secondary pulleys. The belt-slippage diagnostic apparatus includes a slippage determination portion configured to determine occurrence of slippage of the belt on at least one of the primary and secondary pulleys, when a first-order derivative of a gear ratio, which is a ratio of a rotational speed of the primary pulley to a rotational speed of the secondary pulley, is not smaller than a first threshold value and a second-order derivative of the gear ratio is not smaller than a second threshold value.

Belt-slippage diagnostic apparatus for belt-type continuously-variable transmission

A control apparatus for a vehicle drive-force transmitting apparatus including a dog clutch that is operated by an actuator to selectively connect and disconnect a drive-force transmitting path. In process of switching of the dog clutch from released state to engaged state, the control apparatus determines whether a rotational speed difference of the dog clutch is equal to or larger than a given difference value when a sleeve of the dog clutch is positioned on an engaging side of a synchronizing position for placing the dog clutch into the engaged state, and stops the switching of the dog clutch to the engaged state and causes the actuator to place the dog clutch back into the released state, when determining that the rotational speed difference is equal to or larger than the given difference value with the sleeve being positioned on the engaging side of the synchronizing position.

Control apparatus for vehicle drive-force transmitting apparatus

In a control device of a vehicle including a first power transmission path transmitting a power through a belt-type continuously variable transmission and a second power transmission path transmitting a power through a reduction gear mechanism in parallel between an input shaft and an output shaft and including a dog clutch in series with the reduction gear mechanism in the second power transmission path, when the dog clutch is in an engagement transition state and a rotational speed change of the output shaft is equal to or greater than a predetermined value, the engagement transition state of the dog clutch is canceled to release the dog clutch.

Control device of vehicle

An engagement operation of a dog clutch is carried out while an engagement operation of a second clutch is being carried out, that is, during a situation that an uplock is hard to occur because of a phase shift generated between meshing counterpart members of the dog clutch. Thus, the dog clutch is easily engaged, and it is possible to facilitate preparation for transmission of power through a first power transmission path. If the dog clutch is not engaged, the second clutch is engaged and a second power transmission path is established, so it is possible to start moving a vehicle by transmitting power through the second power transmission path. Thus, when the dog clutch is in a non-engaged state at the time of an N-to-D shift during a stop of the vehicle, it is possible to ensure the startability of the vehicle.

Control apparatus for power transmission system

When a power transmission path of a power transmission system is set to a second power transmission path, a continuously variable transmission is controlled at a speed ratio (&#x3b3;) that provides a higher vehicle speed in the case where an input shaft angular acceleration (d&#x3c9;i/dt) is small than in the case where the input shaft angular acceleration (d&#x3c9;i/dt) is large. Therefore, it is possible to control the speed ratio (&#x3b3;) of the continuously variable transmission to a speed ratio (&#x3b3;) that reflects an inertial loss (Tli) of the continuously variable transmission. The inertial loss (Tli) changes with the input shaft angular acceleration (d&#x3c9;i/dt). Thus, in a vehicle in which the continuously variable transmission and a gear mechanism are provided in parallel with each other between an input shaft and an output shaft, it is possible to appropriately reduce a loss of the idling continuously variable transmission.

Control apparatus for vehicle

At the time when a hydraulic actuator is operated to engage a dog clutch, after it is detected that a hydraulic pressure for operating the hydraulic actuator is higher than or equal to a predetermined hydraulic pressure, it is determined whether the dog clutch is not engaged. Therefore, non-engagement determination due to insufficient hydraulic pressure for operating the hydraulic actuator is prevented. Thus, at the time when the hydraulic actuator is operated to engage the dog clutch, it is possible to prevent consumption of time to engage the dog clutch due to unnecessary re-engagement operation.

A vehicle includes a continuously variable transmission, a gear mechanism and a controller. The continuously variable transmission and the gear mechanism are provided in parallel with each other between an input shaft and an output shaft. The controller is configured to i) when the vehicle travels in a state where both a first clutch and a third clutch provided on the gear mechanism side are released, gradually increase a hydraulic pressure of the first clutch such that the first clutch is engaged, ii) calculate a command hydraulic pressure for setting the first clutch to a pressure regulating state on the basis of a command hydraulic pressure of the first clutch at a timing at which the amount of change in an output-side rotation speed of the first clutch becomes larger than a predetermined value, and iii) control the first clutch by using the calculated command hydraulic pressure.

In a control device for a vehicle including: a dog clutch mechanism that is disposed in a power transmission path in which a driving force is transmitted from an engine to a wheel and is operated by a hydraulic actuator; and an electric oil pump that supplies hydraulic pressure to the hydraulic actuator, rotation of the engine is stopped in a state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine stop operation, the rotation of the engine is started in the state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine restart operation, hence occurrence of up-lock of the dog clutch mechanism is prevented.

Vehicle control device and control method

Vehicle control system and method provided to change speed ratio smoothly when switching a power transmission route from a route including a geared transmission to a route including a continuously variable transmission. Vehicle control system applied to a vehicle comprising: continuously variable transmission for changing speed ratio continuously is disposed between input shaft and output shaft; geared transmission is disposed parallel to the continuously variable transmission, and is adapted to establish speed ratio that cannot be established by continuously variable transmission; and friction clutch is brought into engagement to switch torque transmission route from a route including the geared transmission to a route including the continuously variable transmission. Vehicle control system configured to start speed change operation of continuously variable transmission before the friction clutch is brought into engagement completely when switching torque transmission route from the route including the geared transmission to the route including the continuously variable transmission.

Vehicle control system and vehicle control method

When a line pressure is dominated (determined) by at least one of a primary pressure and a secondary pressure during idling of a continuously variable transmission, the hydraulic pressure that is applied to at least one of pulleys, to which the hydraulic pressure larger than a clutch pressure is applied, is reduced. On the other hand, when the line pressure is dominated by the clutch pressure during idling of the continuously variable transmission, the speed gear ratio of the continuously variable transmission is controlled to a lowest speed gear ratio.

Control apparatus for vehicle transmission

In engaging (connecting) a dog clutch by operating a synchromesh mechanism, when there occurs an uplock at the time when a first pressing force is caused to act on a hub sleeve, tooth tips of spline teeth of the hub sleeve contact with tooth tips of spline teeth of a synchronizer ring, and these spline teeth cannot be engaged. However, when a second pressing force is caused to act on the hub sleeve, the uplock is easy to be released. In addition, when torque from an engine is caused to act on the hub sleeve, a displacement is caused to occur in a rotation direction between the mutually contacting spline teeth. Thus, the uplock is reliably released.

Vehicle, control apparatus for vehicle, and control method for vehicle

A first transmission mechanism provided on a first power transmission path and a second transmission mechanism provided on a second power transmission path are provided in parallel with each other between a driving force source and a drive wheel. A first clutch mechanism transmits power or interrupts transmission of power in the first power transmission path. A dog clutch equipped with a synchromesh mechanism transmits power or interrupts transmission of power in the second power transmission path. An electronic control unit is configured to, when changing from the first transmission path to the second transmission path a state where the vehicle is stopping or is stationary and in a state where power of the driving force source is transmitted via the first transmission mechanism, actuate the first clutch mechanism and the second clutch mechanism such that the first clutch mechanism is released and the second clutch mechanism engages.

In a vehicle in which a continuously variable transmission and a gear mechanism are provided in parallel on a power transmission pathway between an input shaft and an output shaft, (i) an electronic control unit performs CVT shifting, in view of shift characteristics of C to C shifting in which the speed ratio is changed in stages, or (ii) then electronic control unit performs C to C shifting, in view of shift characteristics of CVT shifting in which the speed ratio is steplessly changed.

Control system for vehicle

A control system and a control method for a vehicle, the vehicle includes an engine, an input shaft, an output shaft, a continuously variable transmission section, a stepped transmission section and a clutch mechanism, and a control device. The continuously variable transmission section and the stepped transmission section are provided between the input shaft and the output shaft. The clutch mechanism is provided in a torque transmission path between the stepped transmission section and drive wheels. The control device is configured to disengage the clutch mechanism in a case where a vehicle speed is at least equal to a specified value and the engine is stopped.

Control system and control method for vehicle

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Toyota, Japan

Kenji Matsuo