Nec Corporation

Other

Nec Home Electronics, Inc.

Honda Elesys Co., Ltd.

Masahiro Ofuji

Kazunori Jinno

Takashi Saito

Makoto Nagai

Nobuhiro Koyota

Kazutomo Isonaga

Tsutomu Fukui

Satoshi Baba

Yoshitaka Oka

Takashi Inou

Kenji Kumagai

Takashi Saitou

Masanori Sugino

A passenger detection system is presented so that the master control circuit in the system instructs the passenger airbag control circuit controlling the operation of the airbag designated for the passenger seat to be in the deployable state or not-deployable state, depending on the seating conditions of a passenger sitting on the passenger seat, for example whether the passenger is an adult or a child. The passenger detection system is operated by a plurality of antenna electrodes disposed on the passenger seat; an electric field generation device for generating an electric field around an antenna electrode; a switching circuit for connecting the electric field generation device to the various antenna electrodes; an information detection circuit for detecting information related to a current flowing in a particular antenna electrode selected by the switching circuit; a master control circuit for receiving signal data output from the information detection circuit, and judging passenger seating conditions according to the signal data; and an airbag apparatus for controlling the operation of an airbag designated for the driver seat and an airbag designated for the passenger seat.

Passenger detection system and detection method

A passenger detecting system includes a plurality of antenna electrodes provided in a seat, a signal generating section, a detecting section, a switching circuit and a control unit. The signal generating section generates an electrode signal. The switching circuit sequentially supplies the electrode signal to the plurality of antenna electrodes one by one in response to a switching control signal. The detecting section detects change of the electrode signal to generate a detection signal when the electrode signal is supplied to each of the plurality of antenna electrodes. The control unit outputs the switching control signal to the switching circuit and generates a passenger data associated with a passenger on the seat based on the detection signal for each of the plurality of antenna electrodes.

Passenger detecting system and air bag system using the same

A passenger detection system comprises an antenna electrode which is provided to the dashboard of a car, an oscillation circuit for generating a high frequency low voltage oscillation signal in order to generate a weak alternating electric field around the antenna electrode, a current detection section for detecting a transmission current which passes between the oscillation circuit and the antenna electrode depending on the weak alternating electric field which is generated around the antenna electrode, a phase difference detection section for detecting the phase difference between the oscillation signal supplied from the oscillation circuit and an output signal which is supplied to the antenna electrode, and a control circuit for judging the presence or absence of a passenger seated on the seat based on the detected phase difference and judging the distance between the passenger and the dashboard based on the detected transmission current. The passenger detection system is connected with an air bag unit, and the air bag unit is set at a 'no deployment mode' if it is judged that no passenger is seated on the seat or the distance between the passenger and the dashboard is less than a minimum allowable distance, thereby the passenger who is close to the dashboard is protected from secondary injury due to strong deployment of the air bag.

Passenger detection system

A passenger detection system comprises an antenna electrode, an oscillation circuit, a current detection circuit, a phase difference detection circuit, and a control circuit. The antenna electrode is placed on the upper side of a seat. The oscillation circuit generates a high frequency low voltage oscillation signal in order to generate a weak alternating electric field around the antenna electrode. The current detection circuit detects a transmission current which passes between the oscillation circuit and the antenna electrode according to the weak alternating electric field which is generated around the antenna electrode. The phase difference detection circuit detects the phase difference between the oscillation signal supplied from the oscillation circuit and an output signal which is supplied to the antenna electrode. And the presence or absence of a passenger seated on the seat is judged by the control circuit based on the outputs of the current detection circuit and the phase difference detection circuit. Especially, the passenger detection system needs only one antenna electrode, therefore judgment on the presence or absence of a passenger seated on the seat can be executed with simplified circuit composition and low cost.

A passenger detection system including a single antenna electrode mounted on a surface of a passenger seat in an automobile. An oscillator generates an AC current having a predetermined voltage amplitude that is transmitted to the antenna electrode to produce a minute electric field around the antenna electrode. An amplitude control circuit is used to control the voltage amplitude of the output signal from the oscillator. The electrical characteristics of an object on the passenger seat alter the current and phase of the signal in the antenna electrode. A current detection circuit detects the amount of current flowing from the oscillator to the antenna electrode. In addition, a phase differential detection circuit detects a phase differential between the output signal from the oscillator and the signal on the antenna electrode. A control circuit detects the presence or absence of a passenger seated in the seat based on a current signal output from the current detection circuit and a phase differential signal output from the phase differential detection circuit. A control unit including the oscillator, the amplitude control circuit, the current detection circuit, the phase differential detection circuit and the control circuit, is contained in a single housing that is mounted under the passenger seat.

A passenger detecting system is disclosed, that comprises a seat, a plurality of electrodes disposed at predetermined intervals on at least the front surface of the seat, an oscillating circuit for generating a weak electric field between at least one particular electrode (referred to as a first type electrode) of the electrodes and the other electrodes (referred to as second type electrodes), a current/voltage converting circuit for detecting displacement currents that flow corresponding to the weak electric field and for converting the displacement currents into respective voltages, a controlling circuit for detecting a seating pattern of an passenger or the like on the seat corresponding to output signals of the current/voltage converting circuit, and an air bag device for inflating an air bag in case of a collision.

Growing community of inventors

Yokohama, Japan

Masahiro Ofuji