Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Chuo Kenkyusho

Kabushiki Kaisha Toyoda Jidoshokki Seisakusho

Aisin Seiki Kabushiki Kaisha

Masataka Osawa

Ryoichi Hibino

Katsumi Kono

Hiroyuki Nishizawa

Kagenori Fukumura

Norimi Asahara

Kisaburo Hayakawa

Hiroshi Ito

Eiichi Ono

Shinya Nakamura

Takaaki Tokura

Masatoshi Yamada

Toshinari Suzuki

Shu Asami

Yuji Iwase

Kunihiro Iwatsuki

Hiroyuki Yoshida

Hiroyuki Yamaguchi

Hideyuki Suzuki

Tomohiro Asami

Masami Sugaya

Katsumi Nagai

Masuji Oshima

Teruyuki Nishimyou

Shuzo Sanda

Hitoshi Ban

Nobufusa Kobayashi

Takashi Ohta

Hiroaki Kato

Hideo Tomomatsu

Hiroji Taniguchi

Yasuhiro Oshiumi

Kazumi Hoshiya

Masami Kondo

Naoki Yamada

Yoshio Ito

Yuji Muragishi

Toshiaki Ishiguro

Yasunori Nakawaki

Yasunari Nakamura

Takao Watanabe

Yoshikazu Tanaka

Hideki Takamatsu

Yasushi Kobiki

Yuji Nagasawa

Naoki Moriguchi

Naoto Tanaka

Syoichi Sayo

Masakatsu Kuroishi

Fumio Ueda

Kazuyoshi Ogawa

Noriyasu Yamada

Tomohiro Iwai

Masanobu Kimura

Kohta Ohtoshi

Tomohiro Suzuki

Takanori Abekura

Toshinari Sano

Takahito Kondo

A slippage detection system for a continuously variable transmission capable of continuously changing a ratio between a speed of rotation of an input member and a speed of rotation of an output member is provided. The slippage detection system calculates a correlation coefficient relating to the input rotation speed and the output rotation speed, based on a plurality of measurement values of the input rotation speed and a plurality of measurement values of the output rotation speed, and determines slippage of the torque transmitting member in the continuously variable transmission based on the calculated correlation coefficient.

Slippage detection system and method for continuously variable transmissions

A hydraulic control apparatus includes two oil flow control valves () each provided with a supply control portion () for controlling an oil supply from a pressurized oil source, and a discharge control portion () for controlling connection with a discharge passage. One of those oil flow control valves supplies/discharges oil to/from one of hydraulic chambers () that are oppositely formed in a hydraulic servo mechanism. An operation direction of the hydraulic servo mechanism is performed by operating one of the oil flow control valves. The other operation direction of the hydraulic servo mechanism is performed by operating the other oil flow control valve.

Hydraulic control apparatus and hydraulic control method

In a power transmission system for transmitting power of an engine to a load, a planetary gear mechanism provided in parallel to a speed variator combines torque conveyed from the engine with torque conveyed from a motor generator in a state such that their torque ratio equals a predetermined ratio, and transmits the combined torque to a driven wheel. When performing power transmission between the engine and the driven wheel via both the speed variator and the planetary gear mechanism, power distribution between the power conveyed to the speed variator and the power conveyed to the planetary gear mechanism can be actively controlled by adjusting the torque of the motor generator. As a result, the speed variator capacity can be reduced while enhancing power transmission efficiency.

Power transmission system

A controller determines a target gear ratio from an accelerator opening and a vehicle speed. The controller determines the stroke of a trunnion on the basis of the difference between present inclination and a target inclination, thereby to control stroke by a hydraulic control valve. The stroke is corrected according to input/output disc pushing force.

Speed change control apparatus for toroidal CVT

A belt clamping pressure setting device includes: a belt clamping pressure setting unit that sets a belt clamping pressure of a continuously variable transmission that includes an input-side pulley, an output-side pulley, and a belt running between the input-side pulley and the out-side pulley; an input revolution detection sensor that detects a number of input revolutions of the input-side pulley; an output revolution detection sensor that detects a number of output revolutions of the output-side pulley; an input torque detection unit that detects an input torque to the input-side pulley; a reference clamping pressure computing unit that computes a reference clamping pressure, based on the number of input revolutions detected by the input revolution detection sensor, the number of output revolutions detected by the output revolution detection sensor, and the input torque detected by the input torque detection unit; and a belt clamping pressure computing unit that computes the belt clamping pressure to be set by the belt clamping pressure setting unit based on the reference clamping pressure and a correction value computed in accordance with the number of input revolutions detected by the input revolution detection sensor or a torque fluctuation frequency obtained from the number of input revolutions.

Device and method for setting belt clamping pressure

A control apparatus and method control a torque of an engine coupled to an input shaft of an automatic transmission during a shift by that automatic transmission. A torque-down control by which the engine torque is decreased by a predetermined amount is performed, a torque-restore control starting point at which time torque-restore control is to be started is determined, and the torque-restore control so as to gradually restore the engine torque to a value before the torque-down control was performed is started at the torque-restore control starting point. The torque-restore control starting point is determined according to a dynamic model which simulates behavior of the automatic transmission over time from start of the torque-down control, so that a rotational speed of the input shaft of the automatic transmission at a target point substantially matches a target speed.

Control apparatus and method for automatic transmission

The load element state detecting portiondetects the completion of the filling of the hydraulic oil into the clutchand the working limit of the accumulatoron the basis of the displacement of the spool valve element. That is, since the completion of the filling of the hydraulic oil into the clutch and the working limit of the accumulatorare directly detected, so that the completion of the filling of the hydraulic oil into the clutchand the working limit of the accumulatorcan be detected with high precision regardless of differences among products and the time-lapse variation. Furthermore, they can be detected without equipping any special device to the hydraulic control circuit, and thus there is an advantage that the device construction is simple.

State detecting device for load element receiving load of working fluid and state detecting device for fluid pressure control circuit

An engine system includes an engine, continuously variable transmission and a controller. The engine has an engine shaft and plural cylinders. A number of activated cylinders among the plural cylinders is variable. The continuously variable transmission is configured to transmit a rotation of the engine shaft to wheels of a vehicle at a transmission ratio which is continuously variable. The controller is configured to control the engine to change the number of activated cylinders keeping an engine power generated by the engine to be substantially constant.

Engine system with cylinder number variable engine and method for controlling the engine system

The vehicle weight determination device includes a microcomputer for achieving the vehicle weight determination by obtaining a driving force after filtering based on the speed ratio of the torque converter and obtaining an integrated driving force with the absolute value of the driving force after filtering by using an area method. Similarly, acceleration after filtering is obtained by filtering process of the acceleration and an integrated to obtain an integrated acceleration. The vehicle weight is determined by the integrated driving force divided by the integrated acceleration.

Vehicle weight determining device

A friction transmission unit for transmitting power between input and output members by means of friction and capable of loss reduction and large torque transmission. Power is transmitted between a planar disk () and a roller (), which contacts the upper surface of the planar disk (). The profile of the peripheral surface () of the roller () which actually contacts the upper surface () of the disk () is expressed as z=a&#xb7;sin h(bx). This profile realizes a contact stress distribution which is constant over an area corresponding to approximately 80% in the width direction of the entire contact region. This profile also prevents formation of peak stresses near and at the edges of the contact region and, instead, enables formation of monotonic decrease of stress in areas near the edges.

Friction transmission unit

In order to control slip amount of a disengagement side engagement device at the time of a gear shift operation, a target value Nr for rotational speed of an input shaft of an automatic transmission is calculated inside an input shaft speed target value calculating block. Slip control of the disengagement side engagement device is then carried out by controlling engine torque using an engine torque control amount obtained from a engine torque control amount estimation block and the clutch slip amount compensation value calculating section to cause rotation speed Nt of the input shaft to follow the target value Nr. In this way, responsiveness and precision of slip control of the disengagement side engagement device at the time of gear shift operation are improved, and it is possible to improve gear shift shock and to carry out a gear shift operation in a short period of time.

Control device for automatic transmission

An instruction value Duty for bringing a slip rotation speed Nslip to a target rotation speed is feedback-controlled based on a difference e between the slip rotation speed Nslip and the target rotation speed, and a weight &thgr; from a parameter map. Weights &thgr; are assigned individually to a plurality of models, each of which includes a group of parameters and which are used to form a control model that represents a slip control system. Based on a weight that is assigned to one of the plurality of models, a weight that is assigned to at least one model that is other than the one of the plurality of models is specified. Thus, the amount of calculation required can be reduced by estimating weights for the models including the groups of parameters, which contain parameters that are used to construct the control model, instead of directly estimating the control model-constructing parameters.

Weight identification method and feedback control method

When changing gear, engagement side clutch coupling force of an automatic transmission ( ) is controlled in response to an engagement side clutch coupling force control amount set in advance in an engagement side clutch coupling force control amount storage section ( ). A disengagement side clutch coupling force control amount calculating block ( ) has a physical model of the automatic transmission ( ) internally. This disengagement side clutch coupling force control amount calculating block ( ) then calculates disengagement side clutch coupling force control amount from a transmission input torque estimation value estimated by a transmission input torque estimation block ( ), a running resistance estimation value from a running resistance estimation block ( ) and engagement side clutch coupling force control amount using the physical model, and controls the automatic transmission ( ) using the calculated disengagement side clutch coupling force control amount. Since disengagement side clutch coupling force control amount is calculated using a physical model, it is easy to adjust the disengagement side clutch coupling amount. It is also suitable to control engine torque at the time of gear shift, and this engine torque can also be determined using a physical equation.

Controller for automatic transmission

A control apparatus for controlling a control system having a sliding resistance by using a sliding mode control method determines a deviation of an actual value of a quantity of state that is to be caused to follow a target value from the target value (step 1), calculates a switching surface &sgr; from the deviation (step 2), and determines a corrected switching surface &sgr;&prime; by adding a carrier wave to the calculated switching surface &sgr; (step 3). The carrier wave is expressed by a periodic function, for example, a sine wave, a sawtooth pulse wave, or the like, and has finite gradients on its waveform. Then, the control apparatus outputs an amount of operation u based on the value of the corrected switching surface &sgr;&prime; (step 4). The amount of operation u behaves in a manner similar to that in an ordinary sliding mode control method when the switching surface &sgr; is not close to zero. When the switching surface &sgr; is close to zero, the amount of operation u periodically changes similarly to a dither signal. Therefore, the control apparatus is able to prevent deterioration of the controlling performance with respect to the sliding resistance and retain excellent robustness of the sliding mode control.

Control apparatus and method of control system having sliding resistance

A characteristics change of a control object is functionally represented by a parameter &thgr; which varies between values of 0 and 1 as the gain of the control object is surveyed. The frequency of the identification signal is set at a frequency where the difference in gains becomes large. The amplitude of the identification signal is set so that the variation width of the output of the control object is less than or equal to a predetermined value. Because the identification accuracy improves where the input/output characteristics with respect to the parameter are more sensitive, the identification signal set by such a setting apparatus imparts high identification accuracy. Moreover, because the amplitude of the identification signal is set based on the variation width of the output of the control object, identification can be performed without significantly affecting the output of the control object.

Setting apparatus and method for identification signal

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Nagoya, Japan

Masataka Osawa