Hitachi, Ltd.

Fuji Heavy Industries Ltd.

Kinya Fujimoto

Tetsuo Matsumura

Naoyuki Ozaki

Hiroshi Kuroiwa

Yoshiyuki Yoshida

Kentaro Shishido

Takashi Okada

Masashi Seimiya

Toshimichi Minowa

Hiroshi Sakamoto

Tatsuya Ochi

Tomoaki Nitta

A shift control apparatus for an automatic transmission includes a pre-shift device that operates a predetermined synchromesh, based on a prediction by a predicting device. It thereby couples together a transmission input shaft (with a friction transfer mechanism that has not been used to effect a current gear position) and a transmission output shaft, through a predetermined gear train, and brings them into a standby state. The time when it is determined that the friction transfer mechanism that has not been used to effect of the current gear position has been disengaged is taken as the timing with which the synchromesh coupling operation by the standby control is started, regardless of the completion of the achievement of the current gear position.

Apparatus and method for controlling automatic transmission

A transmission control unit predicts a next gear position when a predetermined gear position is achieved. In accordance with a result of the prediction, the transmission control unit operates a predetermined synchromesh to execute a standby control (pre-shift control). In the standby control, a transmission input shaft connected to a friction transfer mechanism not used for achieving a current gear position and a transmission output shaft are connected to each other via a predetermined gear train, and made standby. The transmission control unit makes different from each other an engagement load of the synchromesh when a connection of the synchromesh is done in accordance with the prediction result and an engagement load of the synchromesh when a connection of the synchromesh is done in accordance with the other condition different from the prediction result.

Automatic transmission, control apparatus and control method for the same

A worsening of drivability is to be kept to a minimum by making a fail-safe control taking the state in the event of failure of a shifting operation into account. When clamping a sleeve to a free rotatable gear and during the period after instructing movement of the sleeve to a clamping position until movement of the sleeve to a predetermined positional range which makes it possible to judge that the sleeve has been clamped to the free rotatable gear, a pushing load for the sleeve is increased if the sleeve is in a fixed state near the balk ring, while if the sleeve is in a fixed state near the free rotatable gear, the sleeve is once returned to a neutral position thereof and is re-clamped to the free rotatable gear. Further, the number of times the sleeve is re-clamped to the free rotatable gear is counted and the use of the free rotatable gear is inhibited in accordance with the counted number of times.

Control system and method for automatic transmission

A vehicle clutch has a pushing member that is energized against a friction plane and transfers power from a driving power source when it touches the friction plane. The location of the pushing member can be retained even when power is shut off. After a signal from the key switch ends, the control apparatus stops the driving power source and the vehicle, engages the friction transfer mechanism, and then stops the system.

Vehicle control apparatus

An automobile is equipped with a gear type transmission having a first torque transfer path between input and output shafts formed by mesh type clutches and a second torque transfer path between input and output shafts formed by transfer torque variable systems, and actuators for selecting the torque transfer path. When a wheel slips while the automobile is driving using the first torque transfer path, the actuators are controlled so that at least part of the torque being transferred via the first torque transfer path is instead transferred via the second torque transfer path.

Automobile and control apparatus, and power train system of automobile

At the time of shifting from one gear train among a plurality of gear trains to another gear train, a transmission for controlling a transfer torque variable mechanism and supplementing torque during shifting, during a period of transferring at least a part of torque of an engine by the transfer torque variable means, controls so as to generate engine torque larger than engine torque before the period at least once and carries out shifting.

Method of controlling a vehicle and system of controlling the same

In a torque assisted automated MT, an assist clutch is controlled to ensure that the transmission torque increase rate is reduced when disengaging a dog clutch while engaging the assist clutch. In a twin clutch type automated MT, in stepped speed change, one of the two clutches as the twin clutch is controlled in such a way that the transmission torque increase rate resulting from engagement is reduced with the passage of time, when disengaging the dog clutch prior to speed change while engaging the clutch corresponding to the input shaft in charge of offsetting the torque interruption.

Vehicle control apparatus and control method

Power train control unitcontrols friction clutchwhen shifting from one cogwheel row to the other cogwheel row, sets the target synchronous rotation speed based on the output rotation speed of a transmission and parameters indicative of the state of engineor the transmission, and sets the command value to the friction clutch so that the input rotation speed can be synchronized with the target synchronous rotation speed. Control unitsets the target shifting required time based on parameters indicative of the state of engineor the transmission, and corrects the command value to the friction clutch so that the required shift time can approach the above target shift required time.

Method of controlling a vehicle, apparatus for controlling the same, transmission and apparatus for controlling the same

Friction clutchesand engaging clutchesare arranged between an input shaft and an output shaft of a gear type transmission having a plurality of gear trains. A power train unitcontrols an output shaft torque and an input rotation speed of the transmission during changing speed by estimating or detecting input a torque to the transmission, and detecting an output rotation speed of the transmission, and setting a target shift torque during shifting gear, and setting a command value to the friction clutchesandfrom the target shift torque and the input torque.

Effects caused by unevenness among drive power sources and transmission torque changing apparatus and aging effects in a vehicle transmission are controlled without using sensors. A power train control unit releases engine torque through an assist clutch to release at least a part of gear train transmission torque to shift a meshing clutch toward a release position. During the gear release, a load is applied in a direction in which the meshing clutch is shifted toward the release position, before the transmission torque of the gear train is completely released, and the meshing clutch is shifted to the release position when at least a part of the transmission torque of the gear trains is released.

Method of controlling automobile, automobile control apparatus, transmission, method of controlling transmission and vehicle system

Power train control unit controls friction clutch when shifting from one cogwheel row to the other cogwheel row, sets the target synchronous rotation speed based on the output rotation speed of a transmission and parameters indicative of the state of engine or the transmission, and sets the command value to the friction clutch so that the input rotation speed can be synchronized with the target synchronous rotation speed. Control unit sets the target shifting required time based on parameters indicative of the state of engine or the transmission, and corrects the command value to the friction clutch so that the required shift time can approach the above target shift required time.

Growing community of inventors

Hitachinaka, Japan

Kinya Fujimoto