Denso Corporation

Nippondenso Co., Ltd.

Kariya and Toyota Jidosha Kabushiki Kaisha

Tetsuji Kozaki

Masami Fujitsuna

Takaji Murakawa

Nobuyori Nakajima

Tsutomu Tashiro

Jun Yamada

Mamoru Shimamoto

Yoshifumi Kato

Hiroshi Ishikawa

Motoshi Suzuki

Katsuhiko Hibino

Tatsuya Kitanaka

Hiroshi Enomoto

Yuichi Imani

Koichi Moriguchi

Hirotsugu Ishino

Hajime Yokoyama

Kouichi Moriguchi

Toshio Oonuma

Kouichi Aoyama

Hideaki Yasui

In a range detection device, a movable member has a magnetized portion and can move with a manual valve of a control device. A supporting member includes a plate portion having a surface opposed to the magnetized portion and a recess formed in an opposite surface of the plate portion, and supports the movable member such that the movable member is capable of moving parallel with the plate portion. A substrate is placed in the recess and has a first hole that penetrates the substrate. A magnetic detection element is installed to a surface of the substrate at a side of the plate portion to correspond to a position of the first hole, and detects magnetism of the magnetized portion. A sealing member is filled in the recess and covers the substrate and the magnetic detection element.

Range detection device

In executing an ETC cooperative downshift operation based on a driver's intent to decelerate, this system executes an engine output increasing control (e.g. a combination of a throttle opening control and a fuel injection restoring control) for increasing the engine output irrespective of driver's accelerator operation. At the timing a reduction amount in an input shaft rotational speed Nt exceeds a predetermined value K after the ETC cooperative downshift control is started, it is presumed that the hydraulic pressure of a to-be-disengaged clutch is already reduced to a hydraulic pressure level equivalent to a predetermined transmission torque capacity that causes no undesirable acceleration or shock even if the engine output increasing control is started. And, under such assumption, the engine output increasing control is started at this timing. Accordingly, the present invention can accurately set the start timing of the engine output increasing control so as to suppress any undesirable acceleration or shock caused by the engine output increasing control.

Control apparatus for an automatic transmission and related control method

A hydraulic pressure of each corresponding one of a plurality of friction elements of a gear shift mechanism of the automatic transmission is controlled to downshift the gear shift mechanism from a current gear stage to a next gear stage, at which an engine brake is operated, upon receiving a driver's demand for deceleration. An engine output of the engine is increased by increasing a throttle opening degree of the engine in at least two steps in an absence of a driver's operation on an accelerator of the vehicle at the time of the downshifting of the gear shift mechanism from the current gear stage to the next gear stage.

Control device and method for automatic transmission

An automatic transmission control system equipped with a shift lever position sensor which includes a plurality of switches which output binary signals following a shifting motion of a gear shift lever. Patterns of combinations of the switch outputs are preselected so as to represent positions to which the gear shift lever is manually shiftable. The switches are broken down into two groups each of which produces a binary code carrying information about the position of the gear shift lever to monitor a failure in operation of the shift lever position sensor. The control system also works to perform a deemed D-position hydraulic transmission control to ensure the running of the vehicle even if the shift lever position sensor is failing.

Automatic transmission control system

In performing a down-shift based on a driver's intention of deceleration, an engine output increasing control is started at a time when a transfer torque capacity of the releasing clutch becomes small or zero and the actual oil pressure decreases to an initial oil pressure, not causing an acceleration feeling even upon the engine output increase. For estimating a time when which the real pressure of the releasing clutch decreases to a level of not higher than the initial pressure, the response of the real pressure relative to an oil pressure command value for the releasing clutch is approximated using a transfer characteristic of 'first order lag+time delay.' An estimated real oil pressure obtained based on the transfer characteristic is compared with the initial pressure. It is determined a start timing of the engine output increasing control has been reached upon decrease of the estimated pressure to the initial pressure.

Controller for automatic transmission

When a charge control is applied to a clutch during a shifting operation of an automatic transmission, a charge counter of this clutch is set to a predetermined value. When a drain control is applied to the clutch, the charge counter is counted down. In response to renewal of requested gear position during the shifting operation, a judgment is made as to whether the state of charge is clear with respect to hydraulic fluid supplied to the clutch (i.e. to-be-newly-charged clutch) before the charge control is applied to this clutch for establishing a renewed requested gear position. When the charge counter of this clutch is currently counted down, it is decided that the charged condition of hydraulic fluid supplied to the clutch is unclear. Thus, a multi-stage gear shifting control (i.e. replacement or renewal of target gear position) is prohibited, thereby suppressing generation of shift shock.

Apparatus for controlling an automatic transmission

An automotive automatic transmission control system is provided which is designed to increase the output of an engine in response to a driver's request to downshift a transmission for setting up the engine braking and to load the amount of working fluid to an on-coming clutch quickly during the downshift. The system works to determine whether the loaded amount of working fluid is excessive or lacking using the speeds of an input shaft of the transmission and the engine to correct the amount of working fluid to be used upon a subsequent downshift request. The use of the two speeds enables the fact that the loaded fluid amount is excessive which arises from a rise in the speed of the input shaft caused by the engine output increasing control, not by completion of the loading of the working fluid to the on-coming clutch to be found accurately.

Downshift control for automotive automatic transmission

An automotive automatic transmission control apparatus is provided which works to increase the power of an engine in response to a request to down-shift the gear of an automatic transmission for developing the engine braking. The control apparatus includes a fail-safe circuit working to stop increasing the power of the engine when a defect in operation of a transmission hydraulic control circuit is detected after the hydraulic control circuit starts to control the hydraulic pressures to achieve the downshift of the automatic transmission. This eliminates or alleviates a problem, such as unwanted acceleration of the vehicle during the control of the downshift in the transmission.

A controller of an automatic transmission having a lockup clutch and a control method of the automatic transmission, in which engine rotational speed is prevented from changing even though turbine rotational speed changes at gear shift and slip control can be carried out without making a driver feel uncomfortable are provided. When a speed change command is detected and it is determined that an inertia phase has not yet started, target engine rotational speed during a replenish period is calculated and the target engine rotational speed control is carried out to have the target engine rotational speed. When it is determined that the control is in the inertia phase, another target engine rotational speed during the inertia phase is calculated. Then, target engine rotational speed control in which the engine rotational speed at the start of the inertia phase is maintained as the target engine rotational speed is carried out.

Controller of automatic transmission having a lock up clutch and control method of the automatic transmission

A control apparatus and method for an automatic transmission that prevents incorrect determination of the start of a gear change inertia phase caused by bounding of an input shaft speed, and that prevents delay of the detection of the start of the inertia phase. A working fluid pressure of the frictional element is feedback-controlled in an inertia phase of a gear change transition of a speed-changing gear mechanism, wherein the input shaft speed of the mechanism changes along with an engaging operation of a frictional element of the mechanism. When it is determined that a starting point for the inertia phase control has been reached, inertia phase control is initiated. After a predetermined determination interval subsequently elapses, it is determined whether the inertia phase control should continue.

Control apparatus and method for automatic transmission

A vehicle automatic transmission control controls fluid pressure changes applied to a frictional engagement element which is being changed from an engaged state to a disengaged state at a stage before input shaft rotational speed starts to increase from the beginning of a down-shift control. The control instruction value is set to gradually decrease the applied fluid pressure and to increase the ratio of such decrease with elapsed time. Specifically, a solenoid is used to control the fluid pressure applied to a clutch. The duty-cycle instruction for the solenoid is determined based on a quadratic function expressed as: duty cycle value=initial value-at.sup.2.

Automatic transmission control having variable fluid pressure decreasing

Controller of automatic transmission having a lockup clutch and control

An automotive automatic transmission has an input shaft receiving a rotational force from an engine, an output shaft for outputting a rotational force to a vehicle driving wheel, a frictional engagement device having an adjustable engagement condition, and a transmission device for transmitting a rotational force from the input shaft to the output shaft at a gear speed ratio depending on the engagement condition of the frictional engagement device. A control apparatus for the automotive automatic transmission includes an engagement condition adjusting device for adjusting the engagement condition of the frictional engagement device by feeding a hydraulic pressure thereto in response to an instructed control amount. The control apparatus also includes a control amount calculating device for calculating the control amount such that a time-domain variation in the control amount is along a curve which corresponds to a monotonic increase and whose variation rate gradually increases, or such that a time-domain variation in the control amount is along a curve which corresponds to a monotonic decrease and whose variation rate gradually decreases.

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Aichi-ken, Japan

Tetsuji Kozaki