Toyota Jidosha Kabushiki Kaisha

Toyota Jidosha Kogyo Kabushiki Kaisha

Nippon Soken, Inc.

Nippondenso Co., Ltd.

Takashi Shigematsu

Tomoyuki Watanabe

Setsuo Tokoro

Daisaku Sawada

Takashi Hayashi

Hisasi Kawai

Tokio Kohama

Hideki Obayashi

Toshikazu Ina

Yuji Takeda

Katsuhiro Asano

Yoshikazu Hattori

Masashi Mizukoshi

A driver regards a relative acceleration of a subject vehicle with respect to an object such as a preceding vehicle, an obstacle and the like as one having highest priority, and performs control such that deceleration is immediately started even if a relative velocity is small if the relative acceleration is large. Taking note of this point, the relative acceleration between the subject vehicle and the object is detected, and it is judged whether or not the subject vehicle and the object relatively approach each other at a relative acceleration not less than a predetermined value. A vehicle velocity is controlled such that the relative acceleration is not more than a predetermined target relative acceleration (for which a direction for approach is positive) when the subject vehicle and the object relatively approach each other at a relative acceleration not less than the predetermined value. Thus, the start of deceleration felt by the driver is adequate.

Running control apparatus for vehicles and alarm apparatus for vehicles

A speed ratio control system of a continuously variable transmission for a vehicle is provided, wherein a speed ratio is feedback-controlled in association with a deviation between a target and a measured value, so that the speed ratio can be continuously varied and adjusted. A gain of feedback control or shift speed is utilized, which has been constant or accurately determined, and the gain of feedback control or shift speed is optimally set in accordance with the feedback control, so as to obtain a continuously variable transmission which has high response characteristics and stability.

Speed ratio control system and method for a continuously variable

The leading-vehicle detection apparatus, mounted on a sensing vehicle, radiates a laser beam from a transmitter of a laser radar. The laser beam is reflected by objects including any vehicle in front of the sensing vehicle, and is received by a receiver in the laser radar. The distances between the vehicle and the objects are calculated based on a comparison of the radiated laser beam and the reflected, received laser beam. The calculated distances are stored corresponding to the sweeping positions of the laser beam. Relative speeds between the vehicle and the objects are calculated from the variations over time in the distances. Based on the relative speeds, only the distance information for objects moving at almost the same speed as the sensing vehicle is selected. On the other hand, comparison patterns of inherent vehicular characteristics are stored beforehand. The selected distance information is compared with the comparison patterns. Information matching the comparison patterns is selected. Through this pattern-matching process, distance information for only the leading vehicle is quickly selected. Distance information for a guardrail, a center line, or other objects that are mistaken for moving objects is eliminated.

Leading-vehicle detection apparatus

Method and apparatus for controlling an electromagnetic clutch which is incorporated in a power transmission system of a vehicle to transmit a torque of an engine to drive wheels, when the vehicle is started on a road surface having a low coefficient of friction. The method or apparatus comprises: a step or device for increasing progressively a transmission torque which is transmitted by the electromagnetic clutch; a step or device for detecting a slip of the drive wheels on the road surface; and a step or device for reducing, upon detection of the slip of the drive wheels, the transmission torque of the electromagnetic clutch until the drive wheels have ceased to slip on the road surface.

Method and apparatus for controlling an electromagnetic clutch for use

A continuously variable transmission (CVT) for a motor vehicle. A desired speed ratio of the CVT is defined as a substantially continuous function of a throttle position and a vehicle speed. The desired speed ratio is calculated in accordance with a detected throttle position and a detected vehicle speed. The CVT is controlled in such a way that an actual speed ratio equals the calculated desired speed ratio.

Automatic transmission for automobile and method of controlling same

Method and apparatus for controlling an electromagnetic powder clutch connected to a vehicle engine and including a coil for engaging the powder clutch to transmit an output torque of the engine as a function of an electric current to be applied to the coil such that a variation in the engine torque is absorbed by a slip of the powder clutch. An optimum amount of slip of the powder clutch is determined based on a currently required engine output and a detected output speed of the clutch. A basic control value for controlling a magnitude of the electric current to be applied to the coil is determined based on the detected engine torque, such that the determined magnitude of the electric current permits engagement of the clutch so as to transmit the detected engine output torque. The basic control value is compensated for the determined optimum amount of slip of the clutch, thereby adjusting the transmission torque of the clutch so as to absorb the variation in the output torque of the engine.

Method and apparatus for controlling electromagnetic powder clutch for

An apparatus and method for controlling an electro-magnetic particle clutch is provided. The apparatus includes first through third sensors, a memory, first through fourth calculating devices, first through third determining devices and a controller. The first sensor detects a throttle opening and outputs a first detected signal. The second sensor detects an actual engine revolution speed and outputs a second detected signal. The first calculating device calculates an engine torque in accordance with a first relationship and outputs a first calculated signal. The second calculating device calculates a tentative desired revolution speed and outputs a second calculated signal. The third sensor detects at least one of a plurality conditions in which the vehicle begins moving and outputs at least one of a plurality of detected signals. The first determining device determines a total compensation value in accordance with a third relationship and outputs a first determined signal. The third calculating device calculates a desired revolution speed and outputs a third calculated signal. The fourth calculating device calculates a feed back gain in accordance with a fifth relationships and outputs a fourth calculated signal. The second determining device determines an optimum torque in accordance with a sixth relationship, and outputs a second determined signal. The third determining device determines a control voltage in accordance with a seventh relationship, and outputs the third determined signal. The controller controls electric current supplied to a magnetizing coil of the electro-magnetic particle clutch in accordance with the determined control voltage.

Method and apparatus for controlling electro-magnetic particle clutch

A speed ratio control system for a continuously variable transmission is provided, wherein an oil flowrate to a hydraulic servo of an input or an output V-shaped pulley device is varied by a flow control valve, so that a speed ratio between the input and the output sides can be continuously changed. The system determines a deviation between a target value and a measured value and corrects the measured value in accordance with at least the characteristics of the flow control valve, so that the deviation and a rate of change per unit time of the speed ratio, or the deviation and a rate of change per unit time of a rotational speed of the input or output pulleys, will have a linear relationship over the entire area of control. This system avoids poor feedback gain because of the non-linearity of the characteristics of the flow control valve. Thus, the feedback gain is acceptable over the entire area of control of the continuously variable transmission. Even when the conditions of use are different, the speed ratio (or the input or output rotational speeds) can be stably controlled without disturbing the response.

Speed ratio control system for a continuously variable transmission for

The disclosed apparatus controls an actual drive force of an automotive vehicle equipped with a continuously variable transmission for transmitting an output of an engine to drive wheels. The apparatus includes an output detector for detecting a currently required output of the vehicle; a speed detector for detecting a current speed of the vehicle; a first device for determining a target drive force of the vehicle based on the detected currently required output and the detected current speed of the vehicle, and according to a predetermined relation among the target drive force, the currently required output and the current speed of the vehicle; and a second device for determining the actual drive force of the vehicle. An adjusting device compares the determined target drive force with the determined actual drive force and controls the output of the engine and/or a speed ratio of the transmission, so that the actual drive force of the vehicle coincides with the determined target drive force.

Method and apparatus for controlling drive force of a vehicle equipped

A belt type continuously valiable transmission (CVT) comprises a pair of input pulleys, a pair of output pulleys and a belt trained over input and output pulleys to transmit power. Each pair of the pulleys has a hydraulic cylinder for pressing the pulleys against the belt. A line pressure used in one cylinder is controlled by adjusting an electric pressure regulating valve. A correction value is calculated which corresponds to the square of the rotational speed of the hydraulic cylinder to which line pressure is supplied. The value of control signal of the pressure regulating valve is corrected in accordance with the correction value, so that the error of the line pressure due to a centrifugal force is compensated for.

Power transmission for use in automobiles continuously variable

A method and an apparatus of controlling an electromagnetic clutch incorporated in a power transmission system of a vehicle to transmit an output of an engine to the drive wheels of the vehicle is disclosed. An amount of electric current applied to the clutch is regulated to control an engaging action of said electromagnetic clutch, based on either a variation in rotating speed or torque of an output shaft of the electromagnetic clutch, or based on the frequency or number of variations per unit time in rotating speed or torque of the output shaft, as compared with the frequency or number of ignitions or combustions per unit time of the engine. In this way a variation in output torque of the engine is absorbed by the electromagnetic clutch for improved drivability, while a transmission power loss in the clutch is kept to a minimum for maximum fuel economy.

A continuously variable transmission for use in a motor vehicle. A desired engine speed is defined as a nearby engine speed which produces a minimum specific fuel consumption when the engine generates a horsepower requirement as a function of either accelerator or throttle position. The desired engine speed is calculated in accordance with either the detected accelerator stroke or the detected throttle position and vehicle speed. The continuously variable transmission is feedback controlled such that an actual engine speed equals the calculated desired engine speed.

Power transmission for use in automobiles having continuously variable

In an internal combustion engine, a plurality of engine rotational speeds are detected at predetermined timings for every firing stroke in one cylinder of the engine, and an engine speed variation is calculated as a variation between the square of one of the engine rotational speed and the square of another of the engine rotational speed. A process is performed upon the sequence of the engine speed variations, thus determining an engine combustion state by the processed result.

Method and apparatus for detecting combustion variations in internal

A hydraulic control apparatus for controlling a line pressure utilized in a continuously variable transmission. The apparatus controls the amount of line pressure supplied to be as small as possible without resulting in any slippage between a belt member which spans the pulleys. The apparatus monitors torque on the input shaft and output shaft to determine if any slippage is occurring.

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Susono, Japan

Takashi Shigematsu