Other

Denso Corporation

Nippondenso Co., Ltd.

Nippon Soken, Inc.

Advics Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Densco Corporation

Takeyasu Taguchi

Toshiharu Naito

Yuichi Inoue

Yukio Mori

Hideki Ohashi

Kenji Fujiwara

Takaji Umeno

Motonori Tominaga

Nobuyoshi Onogi

Masaaki Tabata

Kazuhiro Kamiya

Masahiko Kamiya

Masahiro Yonetani

Mamoru Sawada

Osamu Tanaka

Takashi Watanabe

Masahiro Matsuura

Nobuhiko Makino

Ikuo Hayashi

Takeshi Hatoh

Masashi Kishimoto

Hiroyoshi Kojima

Yoshihiro Nishikawa

Hiroyuki Kawai

Hideki Kabune

Shusaku Fujimoto

Yuuichi Inoue

Hiromi Tokuda

Takumo Matsuki

A wheel position identification apparatus includes: braking force fluctuation generating means controlling the braking force-applying means to generate a braking force fluctuation of the wheel independently. The apparatus further includes response probability obtaining means for obtaining a presence, or an absence, of a response of the wheel relative to the braking force fluctuation based upon a wheel rotational speed fluctuation of the wheel. The wheel rotational speed fluctuation is obtained from a rotation state sensor mounted on each wheel. The apparatus still further includes associating means for associating the wheel with the braking force-applying means respectively. The association is based upon a combination of a presence, or an absence, of the braking force fluctuation at each braking force-applying means and the presence, or the absence, of the response obtained by the response probability obtaining means.

Wheel position identifying apparatus for vehicle

In a disc brake control system for a vehicle, a control unit determines that a brake disc is in a condition of a thermal inclination of brake disc, and further determines that the brake disc is restored from the thermal inclination. The control unit operates an actuator of a disc brake devices to push a brake pad to the brake disc, when it determines that the brake disc is restored from the thermal inclination. According to such operation, the brake pad is moved to its normal position to the brake disc, so that a brake drag of the brake pad to the brake disc is suppressed.

Disc brake control system for vehicle

A straight running state is accurately determined using only wheel speed data in any running state. Based upon right and left wheel speed values calculated by a wheel speed calculating mechanism () from detection values of right and left wheel speed sensors (), a wheel speed ratio calculating mechanism (), a distance calculating mechanism (), and a distance ratio calculating mechanism () respectively calculate a right and left wheel speed ratio, an actual running distance, a linear distance, and a distance ratio of the two distances at every preset checkpoint (CP). A wheel speed ratio change amount evaluating mechanism () extracts CPs at times where a change amount of the wheel speed ratio is relatively small as effective CPs, and a determining mechanism () determines an effective CP with the smallest distance ratio from among the effective CPs as in a straight running state.

Straight running judging device for vehicles

A tire air pressure detection device includes an ideal driving status calculating portion () and a rotational status value compensating portion (). The ideal driving status calculating portion calculates an ideal status value (&#x3b2;id) corresponding to a slip value under an ideal driving status without tire slippage. The rational status value compensating portion calculates and ideal rotational status value under the ideal driving status without tire slip based on the regression line calculated by a regression line calculating portion () and the ideal slip status value calculated by the ideal driving status calculating portion.

Tire air pressure detection device for detecting air pressure based on vehicle speed signal

A tire air pressure detection device of the present invention includes a warning anticipation timing calculating portion for anticipating a warning timing at which tire air pressure decrease detecting portion will detect the tire air pressure decrease based on rotational status value compensated for by a rotational status value compensating portion. A tire air pressure decrease detecting portion detects a decrease in tire air pressure when a clocked determination time reaches the warning anticipation timing anticipated by the warning anticipation timing calculating portion.

A tire pneumatic pressure detector includes a tire pneumatic pressure detection unit, a first memory storing data associated with a timing at which the drop of tire pneumatic pressure occurs, a second memory storing second data including one or more of a lapse of time from which the tire pneumatic pressure drop occurs, and third data associated with running distance from the timing when a fault diagnosis signal is input.

Tire pneumatic pressure detector

The invention provides an apparatus and a method of estimating tire air pressure with high accuracy from vehicle operation at low at high speeds regardless of various elements to be mounted to the vehicle. Estimation of tire air pressure based on a resonance frequency extracted based on a wheel speed signal outputted from a wheel speed sensor corresponding to the respective tire and estimation of tire air pressure based on a dynamic load radius derived based on the wheel speed signal, are used to selectively switch in accordance with a magnitude of a variance value of the resonance frequency at a plurality of time points.

Method and apparatus for estimating tire air pressure

Tire air pressure determining apparatus and method of determining tire air pressure

In a tire air pressure warning device, an outside impact such as hydraulic brake pressure is intentionally applied in a pulsating way to a tire when the vehicle substantially stops so as to exert vibration (rotation variation) of the tire axle. Through data processes in analyzing signals of wheel speed sensors that reflect the rotation variation of the tire axle, tire air pressure is estimated for informing to a driver abnormal tire air pressure.

Tire air pressure warning device

In a tire air pressure estimating apparatus, wheel speeds of respective wheels are successively calculated when a vehicle is running. At least one of a tire resonance frequency and a tire spring constant is extracted from vibration frequency components included in a wheel speed signal with respect to each of tires. Tire air pressures of drive wheels are estimated based on the extracted tire resonance frequencies or the tire spring constants. Rotational state values (e.g. wheel speed values) of driven wheel tires are calculated based on the detected wheel speeds. Tire air pressures of driven wheels are estimated based on a deviation of the rotational state values of the driven wheel tires.

Tire air pressure estimating apparatus

A signal processor comprises wheel speed-detecting means for detecting a wheel speed signal including vibrational components of a tire, extraction means for extracting a resonant frequency of the vibrational components of the tire or a tire spring constant based on the wheel speed signals, air pressure-estimating means for estimating a tire air pressure based on the resonant frequency or the tire spring constant, and determining means for determining whether the estimated tire air pressure is abnormal or not by comparing with a determination value. Further, correcting means corrects at least one of the determination value, the estimated tire air pressure, the resonant frequency and the tire spring constant in response to a tire temperature. A temperature-sensing device is mounted inside the signal processor to detect a temperature associated with the tire temperature.

Apparatus for estimating tire air pressure

To achieve both accuracy in correcting sensing error caused by nonstandard factors of a pulse signal generated by rotation of a rotor to be measured and reduction in cost of an apparatus for doing the same, each passage of rotor sensors which rotate integrally with vehicle tires are sensed to produce pulse signals. The pulse signal periods are sequentially integrated every pulse signal train consisting of multiple pulse signals. When all of the pulse signal periods of the pulse signal train are integrated, the integrated value is stored in memory. The memory always stores the integrated values of the newest one rotation of the rotor to be measured. The pulse signal periods are averaged from the sum of the integrated values. With such a construction, the average of the pulse signal periods can be obtained as a learning reference value in the correction without storing all of the pulse signal periods of one rotation, thereby realizing both correction accuracy and cost reduction.

Tire abnormality sensor

An apparatus for estimating an air pressure of a tire of a tired wheel of a motor vehicle, on the basis of a temperature of the tire as well as a motion of the tired wheel, preferably including a temperature-related variable sensor for detecting a temperature-related variable related to the temperature of the tire, and an estimating device for estimating the air pressure of the tire on the basis of the temperature-related variable as well as the motion of the tired wheel.

Apparatus for estimating vehicle tire air pressure from not only tired

Pickup coils which generate vehicle wheel speed signals which include vibration frequency components of tires during vehicle cruising are provided. An electronic control unit extracts resonance frequencies of tires from the vehicle wheel speed signals and estimates tire pneumatic pressure based on the extracted resonance frequencies. When an estimated vehicle wheel pneumatic pressure falls below a predetermined critical pneumatic pressure, pneumatic pressure decline warnings are generated and displayed by a display unit. An update switch is provided and when this update switch is turned on when replacing tires, the electronic control unit adjusts and sets the value of the critical pneumatic pressure described above based on the resonance frequency extracted during this time.

An absolute vehicle speed determining system is provided. This system includes generally a first sensor for detecting an unsprung vibration frequency component acting on a front wheel and a second sensor for detecting an unsprung vibration frequency component acting on a rear wheel. A phase difference between the unsprung vibration frequency components is found to project an absolute speed of a vehicle based on the phase difference and a wheel base of the vehicle. In addition, a tire condition monitoring system is provided which is designed to monitor properties of the tire, for example, the inflation pressure, the type of tire, or the amount of tire wear using the absolute speed of the vehicle projected.

Growing community of inventors

Nagoya, Japan

Takeyasu Taguchi