Nissan Motor Company Limited

Ryohey Toyota

Atsushi Tsukizaki

Masato Koga

Tomoyuki Nakano

Hiromu Terai

Hiroyuki Fukuda

Toshifumi Hibi

Yutaka Kaneko

Kouhei Toyohara

Akira Takano

Hidekazu Yagi

Takashi Kurita

Tomohiro Miyagawa

Kenichi Mori

Mitsunori Kumada

Shinobu Kamada

Kazuhiko Tazoe

Kouichi Kotsuji

Keita Okudaira

Kenichiro Gunji

Kazuhiro Takaki

A method controls a power transmission device including a continuously variable transmission, an electric oil pump provided in a first oil passage connecting primary and secondary pulley oil chambers of the continuously variable transmission, and a switching valve provided at a branch point between the first oil passage and a second oil passage that branches from the first oil passage between the electric oil pump and the primary pulley oil chamber and that is connected to an oil reservoir. A third oil passage branches from the first oil passage between the electric oil pump and the secondary pulley oil chamber. The method makes a magnitude of a hydraulic pressure difference between the third oil passage and the first oil passage one the side of the primary pulley oil chamber smaller than a prescribed threshold value when the switching valve switches between a first position and a second position.

Method for controlling power transmission device and power transmission device

The control mode is switched between a first control mode configured to control the speed change pump based on an actual speed ratio being an actual speed ratio of the variator, and a second control mode configured to control the speed change pump based on an actual working pressure being an actual working pressure of the variator. In the first control mode, the actual speed ratio is calculated based on a detected value of a vehicle speed; and the speed change pump is controlled to cause the actual speed ratio to approach the target speed ratio. In the second control mode, the actual working pressure is detected and the speed change pump is controlled to cause the actual working pressure to approach a target working pressure corresponding to the target speed ratio. In a situation or a condition where the detection accuracy of the vehicle speed by the vehicle speed sensor decreases, the control mode is switched from the first control mode to the second control mode.

Automatic transmission control method and control device

A drive system is provided with a first motor generator as a power source, and a multistage gear transmission for changing the speed of output from the first motor generator and transmitting the output to drive wheels. The multistage gear transmission has a plurality of engagement clutches as shifting elements that are meshingly engaged upon movement from a disengaged position. This hybrid vehicle is provided with a start control device where, when a start clutch has been engaged while the vehicle is stopped, the start control device maintains the engagement of the start clutch for a duration that includes when the vehicle is stopped and until the next vehicle start.

Electrically driven vehicle start control device

A control method of a continuously variable transmission includes supplying oil pressure to a secondary pulley oil chamber by a source pressure oil pump, and controlling a flow of oil into and from a primary pulley oil chamber by an electric oil pump arranged in an oil passage between the primary pulley oil chamber and the secondary pulley oil chamber. After start-up of the source pressure oil pump, an operation of the electric oil pump is restricted until the oil is filled in the oil passage on the secondary pulley oil chamber side of the electric oil pump. The operation of the electric oil pump is permitted when rotation speed of the electric oil pump reaches a predetermined rotation speed.

Control method and control device of continuously variable transmission

A continuously variable transmission control method for controlling entry and exit of oil in a primary pulley oil chamber by an electric oil pump disposed in an oil path between the primary pulley oil chamber and a secondary pulley oil chamber, the control method including: comparing a temperature of the electric oil pump with a first threshold; and restricting a shift amount of a continuously variable transmission when the temperature of the electric oil pump is higher than the first threshold.

Continuously variable transmission control method and continuously variable transmission system

A control method of a continuously variable transmission includes supplying oil pressure to a line-pressure oil passage and a secondary pulley oil chamber by a source pressure oil pump, controlling a flow of oil into and from a primary pulley oil chamber by an electric oil pump arranged in an oil passage between the primary pulley oil chamber and the secondary pulley oil chamber, and limiting a discharge flowrate of the electric oil pump to an amount smaller than a discharge flowrate of the source pressure oil pump.

A continuously variable transmission includes a variator having a primary pulley that has a primary oil chamber, a secondary pulley that has a secondary oil chamber, and a belt looped over the primary pulley and the secondary pulley, wherein secondary pressure is supplied to the secondary oil chamber, an oil pump provided in an oil passage that provides communication between the primary oil chamber and the secondary oil chamber, and a controller. The oil pump is configured to control an inflow and an outflow of oil of the primary oil chamber. The oil pump is formed by a gear pump. The continuously variable transmission controls the oil pump in such a manner that a target speed ratio of the variator is achieved.

Continuously variable transmission and control method of continuously variable transmission

A continuously variable transmission has a primary pulley hydraulic chamber, a secondary pulley hydraulic chamber, a first oil passage connected to the secondary pulley hydraulic chamber, a second oil passage connected to the primary pulley hydraulic chamber, the second oil passage branching from the first oil passage, an electric oil pump provided on the second oil passage so as to allow oil to flow into and flow out from the primary pulley hydraulic chamber, and an oil discharge mechanism configured to discharge oil outside the second oil passage, the oil being to be supplied to the primary pulley hydraulic chamber by the electric oil pump.

Continuously variable transmission and control method thereof

In a hybrid vehicle, rotational speed control on a motor/generator connected to a first engagement clutch is carried out when there is a gear shift request to a gear shift stage at which the first engagement clutch of the multistage gear transmission is meshingly engaged. A transmission control unit is provided for outputting a meshing engagement instruction to the first engagement clutch when a rotational speed feedback control causes a differential rotation speed of the first engagement clutch to be within a range of a synchronization determination rotational speed. Upon executing the rotational speed feedback control on the motor/generator, this transmission control unit reduces the efficacy of the rotational speed feedback control less than before starting of the meshingly engagement, when the meshing engagement of the first engagement clutch is started.

Vehicle transmission control device

A vehicle transmission control device is provided in a vehicle having a gear type transmission capable of selecting a plurality of gear shift patterns, and an electric oil pump for supplying lubricating oil to a gear-shifting mechanism. The vehicle transmission control device includes a transmission controller that selects a path having a small load on the lubricated parts from among the plurality of power transmission paths upon detecting a malfunction has occurred in the oil pump to prevent seizing of lubricated parts and damage to gear-shifting mechanism if a malfunction occurs in the oil pump.

Vehicle shift control device

A mode transition control device is provided for a hybrid vehicle. The mode transition control device reduces a sensation of discomfort that may be imparted to a driver at a time of a mode transition from a series traveling mode to a parallel traveling mode during traveling. During mode transition from the series traveling mode to the parallel traveling mode in a hybrid vehicle, a gear shift stage is selected such that a rotational speed change amount of an internal combustion engine accompanying mode transition is less than or equal to a predetermined threshold value.

Mode transition control device for hybrid vehicle

A control device for a vehicle includes a fuel cell, a motor-generator, a power unit, a transmission, a motor-generator control unit configured to perform a power control on the motor-generator based on a driver request torque, and a generated power control unit configured to control the generated power of the fuel cell based on a load of the fuel cell including the motor-generator. The motor-generator control unit performs a shifting power control for decreasing a rotation speed of the motor-generator during an upshift of the transmission, and a power control on the motor-generator based on a limit torque of the motor-generator during the shifting power control. The limit torque of the motor-generator being calculated based on an actual generated power of the fuel cell per unit time and an acceptable power of the power unit per unit time.

Control device and control method for vehicle

A mode transition control device a hybrid vehicle has a transmission control unit that prevents a second power generation system from overheating while traveling in a series HEV mode. When a battery is at a power generation request threshold value or lower, the vehicle travels in a 'series HEV mode,' in which the first electric motor is utilized as a drive source and receives electrical power from the second motor/generator and the battery. The transmission control unit controls the traveling mode to transition from the 'series HEV mode' to a &#x201c;parallel HEV mode&#x201d; when the vehicle speed has reached a switchover vehicle speed. When a temperature rise of the second power generation system is predicted while traveling in the &#x201c;series HEV mode,&#x201d; the transmission control unit changes the switchover vehicle speed to a slower switchover vehicle speed that was used prior to a determination of the temperature rise.

A power generation control device is provided for a hybrid vehicle that prevents discomfort to an occupant in a traveling scenario in which stops and starts are repeated. The power generation control device includes a power generation controller that selectively carries out series power generation and idle power generation. In series power generation, a first motor/generator is used as the drive source and electric power is generated in a second motor/generator by an internal combustion engine. In idle power generation, electric power is generated in the second motor/generator by the internal combustion engine while the vehicle is stopped. The power generation controller sets a series power generation start threshold of the battery at which series power generation is started, and an idle power generation start threshold of the battery at which idle power generation is started. The series and idle power generation start thresholds are the same value.

Power generation control device for hybrid vehicle

A starting control device is provided for an electrically driven vehicle having an electric motor and an internal combustion engine as drive sources and a transmission shifts and transmits an output of the electric motor to a drive wheel. The starting control device is configured to suppress an abrupt increase in the rotation of the electric motor at the time of an EV start of the vehicle from a released state of a starting dog clutch. In the electrically driven vehicle, an EV start is carried out by transmitting the output of the first motor/generator (MG) to the drive wheel via a starting dog clutch that is meshingly engaged. The output of the first motor/generator is limited until the starting dog clutch comes into a meshed state in which the transmission transmits drive power at the time of start from a released state of the starting dog clutch.

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Kanagawa, Japan

Ryohey Toyota