Occupant judging device for a vehicle seat

• US 20030168895A1
• Filed: 02/12/2003
• Published: 09/11/2003
• Est. Priority Date: 02/12/2002
• Status: Active Grant

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Aoki, Koji, Sakai, Morio, Mori, Masaki, Izawa, Minoru
• Granted Patent: US 7,032,968 B2
• Time in Patent Office: Days
• US Class Current: 297/216.12
• CPC Class Codes: B60R 21/0152 using strain gauges
• CPC Class Codes: B60R 21/01544 detecting seat belt parameters, e.g. length, tension or height-adjustment
• CPC Class Codes: B60R 21/01556 Child-seat detection systems

Abstract

An occupant judging device for a vehicle seat includes a load sensor provided in the vehicle seat and a controller for calculating a detected load value based on an output load value from the load sensor and determining an occupant on the vehicle seat by comparing the detected load value and a predetermined threshold value. The controller judges by a decrease state of the detected load value detected after the seatbelt is fastened being maintained for a first predetermined time that a child restraint device is installed, when a state in which the seatbelt is fastened and the door is opened is detected. Further, the controller judges by a decrease state of the detected load value detected after the seatbelt is fastened being maintained for a second predetermined time that the child restraint device is installed, when a state in which the seatbelt is fastened and the door is closed is detected.

Claims

1. An occupant judging device for a vehicle seat having a load sensor provided in the vehicle seat and a controller for calculating a detected load value based on an output load value from the load sensor and determining an occupant on the vehicle seat by comparing the detected load value and a predetermined threshold value, wherein the device further comprises:

a first detecting means for detecting whether a seatbelt is fastened or not; and

a second detecting means for detecting whether a door is opened or closed, wherein the controller judges by a decrease state of the detected load value detected after the seatbelt is fastened being maintained for a first predetermined time that a child restraint device is installed, when a state in which the seatbelt is fastened and the door is opened is detected, and the controller judges by a decrease state of the detected load value detected after the seatbelt is fastened being maintained for a second predetermined time that the child restraint device is installed, when a state in which the seatbelt is fastened and the door is closed is detected.

2. An occupant judging device for a vehicle seat according to claim 1, wherein the decrease state of the detected load value is represented either by a state in which a ratio of the detected load value to an approximate maximum value of the detected load value detected after the seatbelt is fastened falls below a predetermined ratio, or by a state in which the detected load value falls below a second predetermined value from a value over a first predetermined value.

3. An occupant judging device for a vehicle seat according to claim 1, wherein the first detecting means is a belt anchor switch.

4. An occupant judging device for a vehicle seat according to claim 2, wherein the first detecting means is a belt anchor switch.

5. An occupant judging device for a vehicle seat according to claim 3, wherein the second detecting means is a courtesy switch.

6. An occupant judging device for a vehicle seat according to claim 4, wherein the second detecting means is a courtesy switch.

7. An occupant judging device for a vehicle seat according to claim 1, wherein the load sensor is provided at a sensor bracket having an upper fastener portion, a lower fastener portion, and a bending portion.

8. An occupant judging device for a vehicle seat according to claim 1, wherein the controller includes a CPU, filter, a courtesy switch input circuit, an anchor switch input circuit, and a telecommunication circuit.

9. An occupant judging device for a vehicle seat according to claim 7, wherein the load sensor includes a strain detecting device for electrically detecting a bending degree of the bending portion which bends in response to a weight applied to the vehicle seat.