Occupant classifying device for an automobile

• US 8,581,603 B2
• Filed: 04/20/2010
• Issued: 11/12/2013
• Est. Priority Date: 03/12/2010
• Status: Active Grant

• Current Assignee: Hyundai Mobis Co., Ltd.
• Original Assignee: Hyundai Mobis Co., Ltd.
• Inventors: Hwang, Jae Ho, Park, You Tae, Hwang, Young Soo, Park, Byung Hyuk
• Primary Examiner(s): PATEL, PARESH H
• Application Number:
  US12/763,487
• Publication Number:
  US 20110221453A1
• Time in Patent Office: 1,302 Days
• Field of Search: None
• US Class Current: 324/661
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: B60R 21/0154 in combination with seat heating
• CPC Class Codes: G01D 5/2417 by varying separation
• CPC Class Codes: G01G 19/4142 for controlling activation of safety devices, e.g. airbag systems electrical circuits for triggering safety arrangements in case of vehicle accidents B60R21/015
• CPC Class Codes: G01G 7/00 Weighing apparatus wherein the balancing is effected by magnetic, electromagnetic, or electrostatic action, or by means not provided for in the preceding groups

Abstract

Provided is an occupant classifying device which can detect an occupant sitting on a seat by a change in an electric field between first and second electrodes that is caused by the occupant sitting on the seat. The occupant classifying device includes: a seat for an occupant to sit on; a first electrode disposed in the seat; a second electrode disposed in the seat, spaced apart from the first electrode, and forming an electric field between the first and second electrodes; and a current measuring device for measuring a variation in current value corresponding to changes in the electric field caused by the occupant sitting on the seat.

Claims

1. An occupant classifying device comprising:

a seat for an occupant to sit on;

a first electrode disposed in the seat;

a second electrode disposed in the seat, spaced apart from the first electrode, and forming an electric field between the first and second electrodes;

a current measuring device configured to measure a variation in a current value corresponding to changes in the electric field caused by the occupant sitting on the seat; and

a control unit including the current measuring device configured to classify the occupant sitting on the seat based on the current value and a control part configured to classify the occupant sitting on the seat by comparing a capacitance calculated using the current value with capacitance values preset in the control part,

wherein the capacitance values preset in the control part comprise;

a capacitance value obtained when the seat is empty;

a capacitance value obtained when a child restraint system on which an infant under 1 year old is seated is mounted on the seat;

a capacitance value obtained when a child sits on the seat;

a capacitance value obtained when a female representing the smallest 5% of the female population sits on the seat with a cushion under her buttocks; and

a capacitance value obtained when a female representing the smallest 5% of the female population sits on the seat.

2. The occupant classifying device of claim 1, wherein the capacitance value obtained when the seat is empty is set to 0,

a percentage of the capacitance value obtained when the child restraint system on which the infant under 1 year old is seated is mounted on the seat has a value of 5 or less,

a percentage of the capacitance value obtained when the child sits on the seat has a value of 31 to 42,

a percentage of the capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat with the cushion under her buttocks has a value of 37 to 48, and

a percentage of the capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat has a value of 75 to 100.

3. The occupant classifying device of claim 2, wherein the capacitance values preset in the control part further comprising:

a capacitance value obtained when a mobile phone is on the seat;

a capacitance value obtained when the seat is wet with water;

a capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat with a seat heater for heating the seat being disposed inside the seat; and

a capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat with the seat heater being disposed on the seat.

4. The occupant classifying device of claim 3, wherein a percentage of the capacitance value obtained when the mobile phone is on the seat has a value of 1 or less,

a percentage of capacitance value obtained when the seat is wet with water has an approximate value of 37,

a percentage of capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat with the seat heater being disposed inside the seat has a value of 37 to 48, and

a percentage of capacitance value obtained when the female representing the smallest 5% of the female population sits on the seat with the seat heater being disposed on the seat has a value of 75 to 100.

5. The occupant classifying device of claim 1, wherein the first and second electrodes are disposed on the same plane within the seat.

6. The occupant classifying device of claim 1, further comprising a sensor mat having the first and second electrodes embedded therein.

7. The occupant classifying device of claim 1, wherein the first electrode receives AC power and the second electrode is grounded to the automobile body.

8. The occupant classifying device of claim 1, wherein the first and second electrodes are made of a plate-like body.

9. The occupant classifying device of claim 8, wherein the first electrode is opened at one portion, and the second electrode is inserted into the opened portion.

10. The occupant classifying device of claim 1, wherein the first and second electrodes are made of wires.

11. The occupant classifying device of claim 10, wherein the first electrode comprises:

a plurality of horizontal portions spaced apart from each other and disposed in parallel to each other; and

at least one bent portion connecting one side of the plurality of horizontal portions to a neighboring horizontal portion.

12. The occupant classifying device of claim 11, wherein the second electrode has the same shape as the first electrode and disposed along the first electrode.

13. The occupant classifying device of claim 10, wherein the center of the first electrode is bent so that both ends thereof are symmetrical to each other.

14. The occupant classifying device of claim 13, wherein the second electrode has the same shape as the first electrode and is disposed symmetrically to the first electrode.

15. The occupant classifying device of claim 10, wherein the first electrode comprises:

a first linear portion extending straight; and

at least one first projection and first recess bent from the first linear portion and formed alternately to each other.

16. The occupant classifying device of claim 15, wherein the second electrode comprises:

a second linear portion extending straight; and

at least one second projection and second recess bent from the second linear portion and formed alternately to each other.

17. The occupant classifying device of claim 16, wherein the first projection is inserted into the second recess, and the second projection is inserted into the first recess.

18. The occupant classifying device of claim 1, wherein the first electrode and the second electrode are printed on a flexible printed circuit board.