Mitsuba Electric Manufacturing Co., Ltd.

Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kogyo K.k.

Mitsuba Electric Mfg. Co., Ltd.

Mitsuru Matsui

Masahiko Asakura

Norimitsu Kurihara

Kazuhiko Tachikawa

Yasuhiko Otsuka

Hidehiko Anzai

A method for computing a current vehicle speed value from a detected vehicle speed value derived from a pulse signal, said method provided data which can be used in a control process such as a cruise control of a vehicle, in which the current vehicle speed value is predicted from a previously computed vehicle speed value after an abnormal state of the current detected vehicle speed value is detected; and a cancel signal is produced for aborting the control process when the abnormal state has persisted for more than a certain time period. Thus, the derivation of an abnormal computed vehicle speed value is prevented when a temporary abnormal condition of the detected vehicle speed value has occurred, and a cancel signal, which may be used for aborting the operation of the control process, is produced when the abnormal condition of the detected vehicle speed has persisted for more than a certain time period, whereby the control system can respond to the abnormal conditions of the detected vehicle speed value in optimal fashion, and convenience and safety are both maximized.

Method for computing a value of speed from a pulse signal

A cruise control system for maintaining the speed of a vehicle at a fixed, set speed, comprising an actuator including an electric motor which actuates a speed control member via an electromagnetic clutch. To ensure the capability of the cruise control system to decelerate the vehicle even when it is traveling a steep and long downhill, and the normal operation of the cruise control system becomes inadequate for curbing the excessive increase of the vehicle speed, the electromagnetic clutch is disengaged whereby the speed control member is returned to the position for maximum deceleration. Since the operation of the cruise control system is not canceled even when the vehicle speed is increased substantially beyond the set speed, the cruise control system can readily return to its normal operation even after the vehicle is accelerated from the state of cruise control by stepping on the accelerator pedal, for instance for passing another car. To avoid frequent activation of the electromagnetic clutch, there may be defined an intermediate speed range in which a boosted deceleration signal is supplied to the electric motor for a deceleration action which is more boosted than a normal deceleration signal.

Cruise control system

A vehicle cruise control system, comprising a control circuit for producing a control signal for maintaining a speed of a vehicle at a fixed level according to a difference between an actual vehicle speed and a target vehicle speed, and a drive circuit for producing a drive signal for selectively driving an actuator in a direction either to accelerate the vehicle or to decelerate the vehicle according to the control signal from the control circuit. The drive circuit is provided with a transistor bridge circuit comprising four drive transistors for producing the drive signal. The control circuit is provided with a detection means for detecting an abnormal state of the system and an inhibiting means which brings at least one of the drive transistors into an non-conductive state when any abnormal state is detected by the detecting means. The control circuit may be programmed to perform a certain diagnostic procedure for testing the soundness of the drive transistors. Thus, erratic behavior of the cruise control system and destruction of the drive transistors can be effectively prevented.

Vehicle cruise control system

Growing community of inventors

Gumma, Japan

Mitsuru Matsui