Abstract: A keyless entry system for operating a vehicular door lock device between a first door locking position and a second door unlocking position. The system has an electrically drivable actuator associated with the vehicular device for operating the latter between the first and second positions, a radio signal transmitter of a size equivalent to a credit-card, and being triggerrable by a trigger command and generating a radio code signal containing a preset identification code, the radio signal transmitter having a first antenna.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which in addition to a control unit and a throttle actuator through which an opening angle of an engine throttle valve is adjusted so that the vehicle speed detected by a vehicle speed sensor coincides with a target cruise speed set by a vehicle driver through a set switch, a vehicle speed determining circuit is provided for determining whether the vehicle speed detected by the vehicle speed sensor exceeds a lowest speed limit above which the cruse control by the control unit and throttle actuator becomes effective. When the vehicle speed is below the lowest speed limit, the power supply to the throttle actuator is interrupted so that the cruise control by means of the throttle actuator is cancelled.

Abstract: A radio signal transmitter for use in an automotive keyless entry system, is resistant to damage even when subject bending stresses. The radio code transmitter has a thin housing. A substrate for a transmitter circuit is housed within the thin internal space of the housing. A plurality of circuit components making up the transmitter circuit are mounted on the substrate. The circuit components are arranged in such a manner that relatively large components are near the edges of the substrate and relatively small components are nearer the center of the substrate.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed includes an inhibit switch connected in parallel to a line between a power supply and a main self hold power supply switch (self-hold type) of an automatic cruise controlling system. When the vehicle speed is below a predetermined value, the inhibit switch is open so that the automatic cruise speed controlling system cannot receive power via the main, switch. Thus, wasteful comsumption of power is reduced.

Abstract: A cruise control system for an automotive vehicle with a manual or automatic transmission, includes an inhibition circuit. The inhibiting circuit blocks communication between a power supply and an actuator and/or a controller when the manual transmission is set in a predetermined gear or when the automatic transmission is set in a driving range other than the drive range, so as to inhibit the controller from operating in the cruise control mode. When the vehicle is provided with an automatic transmission which is selectively set in first, second, third or fourth gear while the shift lever is set in the drive range position, the cruise control system includes a first inhibiting circuit which blocks the communication when the shift lever is set in a position other than the drive range position, and a second inhibiting circuit which blocks the communication when the automatic transmission is set in either the first or second range while the shift lever is set in the drive range position.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which a vehicle speed sensor which output an analog quantity corresponding to a current vehicle speed is provided, a vehicle speed determining circuit which derives the current vehicle speed on the basis of the analog quantity derived from the vehicle speed sensor and determines whether the derived current vehicle speed is below a predetermined speed above which the cruise speed control run is appropriate is furthermore provided independently of a control unit of the system. When the vehicle speed determining circuit outputs a determination signal indicating that the current vehicle speed is below the predetermined speed and the control unit outputs a predetermined control command signal, a power supply line connected to a throttle valve actuator is, at first, interrupted. Then, the power supply to the control unit is interrupted.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which whether a microcomputer of a control unit is enabled to perform a cruise speed control is determined on the basis of a plurality of determining factors and a power supply of a throttle actuator for actuating an engine throttle valve so as to adjust an opening angle of the throttle valve is enabled only when all of the determining factors satisfy a condition of enabling the cruise speed control via the actuator and is disabled when at least one of the determining factors does not satisfy the condition.

Abstract: A keyless entry system employs a pocket-portable radio signal transmitter to be carried by a user and a controller mounted on a vehicle and associated with a vehicle device, such as a door lock mechanism, a trunk lid opener, a window regulator, a steering lock device and so forth, to be operated. Radio signal communication between the transmitter and the controller is performed by electromagnetic induction. According to the present invention, electromagnetic induction is caused between antennas in the transmitter and the controller. In order to provide wide communication area, at least the antenna of the controller serves as a transformer to generate higher loop current for generating sufficiently strong magnetic field therearound.

Abstract: A system and method for automatically controlling a vehicle speed to a desired cruise speed are disclosed in which whether after any one of command and release signals is outputted from the corresponding set/cruise, acceleration, resume, brake, clutch, and cancel switches, a control unit outputs a corresponding receipt signal via a corresponding output port is determined, whether the contents of the control command signals presently outputting through the respective control valves are equal to inverted levels at the respective control valve is determined, and a power supply to control valves for adjusting an operating variable of an engine driving force adjusting mechanism and the control unit is interrupted when at least one of the results of determinations indicates a negative result.

Abstract: In a ratio-mediated keyless entry system for an automotive vehicle, two vehicle-mounted antennae, lying in mutually perpendicular planes are used to receive radio signals from a portable, manually operable transmitter. When the transmitter is left in the passenger compartment and then the doors are locked, the system generates an alarm to notify the driver of the fact. On antenna completely encircles the passenger compartment. Encircling the passenger compartment with one of the vehicle-mounted antennae ensures that wherever the transmitter is left in the passenger compartment, its presence will be detected no matter how limited the transmitter's range.

Abstract: A keyless entry system has a controller mounted on the vehicle which generates a radio signal for triggering a portable radio signal transmitter. The transmitter triggering radio signal of the controller contains a preset triggering code. The portable transmitter receives the transmitter triggering radio signal from the controller to compare the triggering code with a preset code to generate a transmitter identifying code containing radio signal when the triggering code matches the preset code in the portable transmitter. The controller receives the transmitter identifying code containing radio signal to compare the received code with a preset code to output a control signal for operating a preselected vehicle device when the received code matches the preset code in the controller.

Abstract: A method for detecting an encoded radio signal involves comparing the received signal amplitude with a predetermined threshold amplitude. The difference between the received signal-component amplitude and the noise-component amplitude is derived and used to adjust the threshold amplitude. By adjustng the threshold amplitude depending upon the difference between the signal-component amplitude and the noise-component amplitude, mis-detection which could occur otherwise when the reception amplitude of the noise component is relatively high or the reception amplitude of the signal component is relatively low can be successfully and satisfactorily avoided.

Abstract: A keyless entry system allows fully automatic operation of a door lock device of an automotive vehicle. The system recognizes the presence and absence of an authorized user and automatically locks or unlocks the vehicle door lock device according to the presence or absence of the authorized user. The keyless entry system is provided with a controller mounted on a vehicle and designed to periodically generate a radio demand signal and transmit same at regular intervals. A radio code signal transmitter is normally in a stand-by state in which it is ready to transmit a radio code signal indicative of a preset code in response to the radio demand signal. The radio code signal transmitter is of a pocket-portable size for convenient transport by an authorized user. The radio signal transmission between the controller and the radio code signal transmitter is performed within a predetermined distance range around the vehicle.

Abstract: An antenna for an automotive keyless entry system can ensure radio-wave transmission between a transmitter and a controller and can be conveniently mounted on a vehicle body. The antenna for an automotive keyless entry system, has a first planar antenna loop, and a second antenna loop disposed within the first antenna loop and lying in the plane thereof. The axis of the second antenna loop is substantially perpendicular to the axis of the first antenna loop. The first and second antenna loops form an antenna assembly which can be conveniently mounted on the vehicle body as, for example, within a door mirror of the vehicle.

Abstract: A keyless entry system can lock and unlock an automotive vehicle door, a trunk lid, a glove box and/or a steering column without an ignition key. The system comprises a transmitter producing a radio signal indicative of a preset unique code, and a controller receiving the radio signal and performing desired locking or unlocking operation when the code from the transmitter matches a preset code. A manual switch is provided to order the transmitter to transmit the code-indicative radio signal to the controller. The controller is disabled when a preselected vehicle condition is detected, for example the ACC or ON position of an ignition switch or the presence of an ignition key in an ignition key hole.

Abstract: A keyless entry system for an automotive vehicle allows operation of a vehicle device or devices without the need for an ignition key or other mechanical keys. A user can simply depress a single push-button or operate another suitable type of switch to activate the system and operate the desired vehicle device to the desired position. The system generally comprises a pocket-portable radio signal transmitter and a controller mounted on the vehicle and associated with the vehicle device. The transmitter has a small, long-life battery and the controller receives electric power from the vehicle battery. Power conservation for both the transmitter and the controller is achieved by activating them for limited periods in response to operation of the manual switch.

Abstract: A keyless entry system allows operation of various vehicle devices including a door lock without using a mechanical key, such as an ignition key. The system comprises a wireless, portable transmitter adapted to produce a radio signal indicative of a unique code preset in the transmitter, and a controller mounted on the vehicle and associated with the vehicle devices. The controller has a preset code to compare with the unique code indicative in the radio signal transmitted from the transmitter. The controller also detects impending or accomplished locking of the transmitter in the vehicle and produces an alarm and subsequently disables the keyless entry system unless the transmitter is removed from the vehicle within a given period of time after the alarm is given.