Vehicular Airbag Device

• US 20170014078A1
• Filed: 02/12/2015
• Published: 01/19/2017
• Est. Priority Date: 04/04/2014
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Yamazak, Yuki i, Harada, Tatsuya, Midorikawa, Yukinori
• Granted Patent: US 11,172,887 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0245 by using sensing means generating electric signals, i.e. ECG signals
• CPC Class Codes: A61B 5/6893 Cars
• CPC Class Codes: A61B 5/7225 Details of analog processing, e.g. isolation amplifier, gain or sensitivity adjustment, filtering, baseline or drift compensation A61B5/30, A61B5/316 take precedence; transformers for specific applications H01F38/00; amplifiers H03F
• CPC Class Codes: B62D 1/046 Adaptations on rotatable parts of the steering wheel for accommodation of switches
• CPC Class Codes: B62D 1/065 Steering wheels with heating and ventilating means heating and ventilation of steering wheel when connected to vehicle HVAC B60H1/00292
• CPC Class Codes: H05B 1/0236 for vehicles
• CPC Class Codes: H05B 2203/037 Heaters with zones of different power density
• CPC Class Codes: H05B 3/03 Electrodes

Abstract

An occupant information sensing device 100 includes a plurality of heater electrodes that are provided at a vehicle steering wheel 104 and insulated and separated from one another and that generate heat by conduction. Power sources provide electrical current for heater electrodes. Electrical circuit elements enable the system to provide occupant biological condition monitoring, gripping detecton, and electrical stimulation. The circuits enable common electrical connecting to the heater electrodes to provide multiple functions through the use of filtering and time division multiplexing.

Claims

1. An occupant information sensing device, comprising:

at least two heater electrodes that are provided at a vehicle steering wheel and electrically separated from one another and that generate heat by conduction;

at least one heater power source that feeds power to the at least two heater electrodes; and

a signal processing circuit that is connected to the at least two heater electrodes and processes an occupant information signal output from the at least two heater electrodes.

2. The occupant information sensing device according to claim 1, further comprising wherein the at least one heater power source is in the form of an insulated type DC power source and a capacitor connected to an input portion of the signal processing circuit.

3. The occupant information sensing device according to claim 1, further comprising a switching element that is provided in a circuit from the at least one heater power source to the at least two heater electrodes and that establishes a conduction state or a non-conduction state between the at least one heater power source and the at least two heater electrodes.

4. The occupant information sensing device according to claim 1, further comprising a control circuit that switches the switching element by time division multiplexing, wherein

the control circuit connects the at least two heater electrodes to one of the heater power source and the signal processing circuit at prescribed time intervals.

5. The occupant information sensing device according to claim 1, further comprising wherein the signal processing circuit includes a heartbeat detecting circuit that detects a heartbeat of an occupant by differentially amplifying heartbeat signals from the occupant output from the at least two heater electrodes.

6. The occupant information sensing device according to claim 1 further comprising, wherein the signal processing circuit further includes a first signal generating circuit that inputs a first signal to one of the at least two heater electrodes and a gripping detecting circuit that detects a state of gripping the steering wheel by the occupant on the basis of a second signal, the first signal that has passed through the occupant in contact with one and the other of the at least two heater electrodes being output from the other as the second signal.

14. The occupant information sensing device according to claim 1 further comprising circuit elements for providing electrical stimulation of the occupant.

15. The occupant information sensing device according to claim 1 further comprising the power source is provided in the form of an AC power source.

7. An occupant information sensing device, comprising:

a at least two heater electrodes that are provided at a vehicle steering wheel and insulated and separated from one another and that generate heat by conduction;

a heater power source in the form of an AC power source that feeds power to the at least two heater electrodes and that is grounded commonly for the heater electrodes;

a filter that is provided in a circuit from the heater power source to the heater electrode to pass a frequency of the AC power source of the heater power source and blocks a frequency of an occupant information signal output from the heater electrode; and

a signal processing circuit that processes the occupant information signal, wherein

the AC power source of the heater power source uses a frequency different from the occupant information signal, and

an input portion of the signal processing circuit is connected between the filter and the at least two heater electrodes.

8. The occupant information sensing device according to claim 7, further comprising a switching element provided in a circuit from the second heater power source to the at least two heater electrodes, wherein

the switching element establishes a conduction state or a non-conduction state between the heater power source and the at least two heater electrodes.

9. The occupant information sensing device according to claim 8, further comprising a control circuit that switches the switching element by time division multiplexing, wherein

the control circuit connects the at least two heater electrodes to one of the heater power source and the signal processing circuit at prescribed time intervals.

10. The occupant information sensing device according to claim 7, further comprising:

the occupant information signal is a heartbeat signal from an occupant,

the signal processing circuit includes a heartbeat detecting circuit that detects heartbeat signals from the occupant output from the at least two heater electrodes, and

the filter is a high-pass filter that blocks a frequency of the heartbeat signal.

11. The occupant information sensing device according to claim 7 further comprising:

the occupant information signal is a gripping state detection signal indicative of a state of gripping the steering wheel by the occupant,

the signal processing circuit further includes a first signal generating circuit that inputs a first signal to one of the at least two heater electrodes and a gripping detecting circuit that detects the state of gripping the steering wheel by the occupant on the basis of a second signal included in the gripping state detection signal, the first signal that has passed through the occupant in contact with one and the other of the at least two heater electrodes being output from the other as the gripping state detection signal, and

the filter is a low-pass filter that blocks a frequency of the gipping state detection signal.

12. The occupant information sensing device according to claim 7 further comprising:

the occupant information signal is a heartbeat signal from the occupant and also is a gripping state detection signal indicative of a state of gripping the steering wheel by the occupant,

the signal processing circuit includes

a heartbeat detecting circuit that detects heartbeat signals from the occupant output from the at least two heater electrodes,

a first signal generating circuit that inputs a first signal to one of the at least two heater electrodes, and

a gripping detecting circuit that detects the state of gripping the steering wheel by the occupant on the basis of a second signal included in the gripping state detection signal, the first signal that has passed through the occupant in contact with one and the other of the at least two heater electrodes being output from the other as the gripping state detection signal, and

the filter is a band-pass filter that blocks a frequency of the heartbeat signal and a frequency of the gripping state detection signal.

13. An occupant information sensing device, comprising:

a plurality of heater electrodes that are provided at a vehicle steering wheel and insulated and separated from one another and that generate heat by conduction;

a heater power source of a non-insulated type AC power source that feeds power to at least two heater electrodes of the plurality of heater electrodes and that is grounded commonly for the heater electrodes;

a signal processing circuit that processes an occupant information signal output from the heater electrode;

a switching element that is provided in a circuit from the second heater power source to the heater electrode and establishes a conduction state or a non-conduction state between the second heater power source and the heater electrode; and

a control circuit that switches the switching element by time division and connects the heater electrode to one of the second heater power source and the signal processing circuit at prescribed time interval.

16. The occupant information sensing device according to claim 13 further comprising a control circuit that switches the switching element by time division multiplexing, wherein

the control circuit connects the at least two heater electrodes to one of the heater power source and the signal processing circuit at prescribed time intervals.

17. The occupant information sensing device according to claim 13 wherein the signal processing circuit includes a heartbeat detecting circuit that detects a heartbeat of an occupant by differentially amplifying heartbeat signals from the occupant output from the at least two heater electrodes.

18. The occupant information sensing device according to claim 13 further comprising, wherein the signal processing circuit further includes a first signal generating circuit that inputs a first signal to one of the at least two heater electrodes and a gripping detecting circuit that detects a state of gripping the steering wheel by the occupant on the basis of a second signal, the first signal that has passed through the occupant in contact with one and the other of the at least two heater electrodes being output from the other as the second signal.