Occupant detection system

• US 20040040390A1
• Filed: 08/08/2003
• Published: 03/04/2004
• Est. Priority Date: 08/30/2002
• Status: Active Grant

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Nagai, Makoto, Kojima, Mikihito, Nishide, Harutomi, Suzuki, Yoshitaka, Koyota, Nobuhiro, Isonaga, Kazutomo, Tosa, Mitsugu
• Granted Patent: US 6,928,889 B2
• Time in Patent Office: Days
• US Class Current: 73/862.52
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: B60R 21/0152 using strain gauges
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• 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

Abstract

An occupant detection system, which has a sensor, a controller, a base frame, and a heat insulator.

In this occupant detection system, the sensor measures a weight of an occupant sitting on said vehicle seat. The controller detects a presence of said occupant on said vehicle seat. The base frame is fixed to one of a vehicle seat or a vehicle body and accommodates the sensor. The heat insulator is provided on said base frame and prevents a heat transfer between said base frame and said sensor.

Claims

1. An occupant detection system comprising:

a sensor, which measures a weight of an occupant sitting on said vehicle seat;

a controller, which detects a presence of said occupant on said vehicle seat;

a base frame, which is fixed to one of a vehicle seat and a vehicle body and accommodates said sensor; and

a heat insulator, which is provided on said base frame and prevents a heat transfer between said base frame and said sensor.

2. An occupant detection system according to claim 1, wherein

said sensor is a strain gage, which includes a plurality of resistive elements, and

said sensor has a thermal conductive substance, which decreases a temperature difference among said resistors.

3. An occupant detection system comprising:

a weight detection unit, which is placed between a bottom of a vehicle seat and a floor of a vehicle, wherein

said weight detection unit includes

a load receiver, which receives a load applied to said vehicle seat,

a load detector, which generates a signal in compliance with a load received by said load receiver,

a load transmitter, which transmits a load received by said load receiver to said load detector, and

a receptacle, which accommodates said load detector, said load receiver, and transmitter;

a control unit, which determine whether an occupant is on said vehicle seat based on said signal generated by said vehicle seat; and

a heat insulator, which is provided on the top surface of said receptacle and prevents a heat transfer from said receptacle to said load detector.

4. An occupant detection system according to claim 3, wherein,

said load detector comprises:

a sensor plate, which receives a load that is received by said load receiver and is transmitted through said load transmitter; and

a strain gage, which is placed on said sensor plate, and measures distortion of said sensor plate that are caused by said load transmitted through said load transmitter;

wherein

said control unit determine whether an occupant is on said vehicle seat based on a level of a load which is estimated from said distortion of said strain gage.

5. An occupant detection system according to claim 4, wherein

said sensor plate comprises:

a fixing part, which is fixed to said receptacle; and

a pair of displacement parts, which are provided at the both sides of said fixing part, wherein

one side of said displacement part is connected to said fixing part through a path, and the other side of said displacement part is connected to said load transmitter.

6. An occupant detection system according to claim 4, wherein said path has a pair of strain gages, one of which is placed at vicinity of said fixing part, and the other of which is placed at vicinity of said displacement part.

7. An occupant detection system according to claim 6, wherein

said control unit measures electric resistance of each of said strains gages, and determines whether an occupant is on said vehicle seat based on said electric resistance.

8. An occupant detection system according to claim 5, wherein

said sensor plate has at least one thermal conductive substance, which connect said fixing part, said path, and said displacement part, each other, whereby

the temperature of said fixing part, said path, and said displacement part are equalized.

9. An occupant detection system according to claim 3, wherein

said weight detection unit is composed of

a first weight detection unit, which is placed at one side in the width direction of said vehicle seat, and a second weight detection unit, which is placed at other side in the width direction of said vehicle seat, and wherein

said control unit further determine whether an occupant is sitting on either sides of said vehicle seat by comparing the signal, which is generated by said load detector of said first weight detection unit, with the signal, which is generated by said load detector of said second weight detection unit, and then said control unit

10. An occupant detection system according to claim 3, wherein

said control unit determines whether an occupant sitting on said vehicle seat is adult by comparing the signal generated by said load detector with a threshold value.