OCCUPANT DETERMINATION APPARATUS USING LOAD SENSOR

• US 20140291041A1
• Filed: 03/21/2014
• Published: 10/02/2014
• Est. Priority Date: 03/29/2013
• Status: Active Grant

• Current Assignee: DENSO Corporation, Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: DENSO Corporation
• Inventors: Hosokawa, Toshio
• Granted Patent: US 9,541,446 B2
• Time in Patent Office: Days
• US Class Current: 177/136
• 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 determination apparatus includes a load sensor and a determination section. The load sensor detects a load of an occupant seated in a seat of a vehicle to provide the detected load as a load signal. The determination section determines presence or absence of the occupant and a physical size of the occupant by classifying the load signal into a subject class among a plurality of classes that are ordered from small to large according to the physical sizes based on predetermined threshold loads. The subject class is stored as a determined class. The determination section permits the determined class to transition from a present class to an immediately adjacent larger class when the load signal equal to or larger than a threshold load between the present class and the immediately adjacent larger class continues being received for a threshold time.

Claims

1. An occupant determination apparatus comprising:

a load sensor to detect a load of an occupant who is seated in a seat of a vehicle and provide the detected load as a load signal; and

a determination section to receive the load signal and determine (i) presence or absence of the occupant and (ii) a physical size of the occupant by classifying the load signal into a subject class among a plurality of classes, which are ordered from small to large according to the physical size, based on predetermined threshold loads, the subject class being stored as a determined class,

wherein

the determination section performs an inter-class transition that permits the determined class to transition from a present class to an adjacent class that is immediately adjacent to the present class (i) when the load signal equal to or larger than a first threshold load, which is defined between the present class and the adjacent class that is larger than the present class, continues being received for a first threshold time, or (ii) when the load signal smaller than a second threshold load, which is defined between the present class and the adjacent class that is smaller than the present class, continues being received for a second threshold time.

2. The occupant determination apparatus according to claim 1, wherein:

a plurality of threshold times including the first threshold time and the second threshold time are assigned to inter-class transitions each that permit the determined class to transition from the present class to the adjacent class being referred to as a transition destination class;

a class, which is initially determined as the determined class when the occupant gets in the vehicle, is defined as a basis class among the plurality of classes; and

as the transition destination class is farther from the basis class, a threshold time corresponding to the inter-class transition into the transition destination class is designated to be longer.

3. The occupant determination apparatus according to claim 1, wherein:

a plurality of threshold times including the first threshold time and the second threshold time are assigned to inter-class transitions each that permit the determined class to transition from the present class to the adjacent class being referred to as a transition destination class;

a class, which is stored as the determined class when a vehicle speed signal from a speed sensor (5) in the vehicle provided to the determination section reaches a predetermined value, is defined as a basis class among the plurality of classes; and

as the transition destination class is farther from the basis class, a threshold time corresponding to the inter-class transition into the transition destination class is designated to be longer.

4. The occupant determination apparatus according to claim 1, wherein:

a plurality of threshold times including the first threshold time and the second threshold time are assigned to inter-class transitions each that permit the determined class to transition from the present class to the adjacent class being referred to as a transition destination class;

the plurality of classes include (i) an airbag-inflating class that enables inflating of an airbag and (ii) a none-airbag-inflating class that disables inflating of the airbag;

the plurality of threshold times include (i) a third threshold time that is defined for the inter-class transition between the airbag-inflating classes and (ii) a fourth threshold time that is defined for the inter-class transition between the airbag-inflating class and the none-airbag-inflating class; and

the third threshold time between the airbag-inflating classes is designated to be longer than the fourth threshold time between the airbag-inflating class and the none-airbag-inflating class.

5. The occupant determination apparatus according to claim 1, wherein:

a plurality of threshold times including the first threshold time and the second threshold time are assigned to inter-class transitions each that permit the determined class to transition from the present class to the adjacent class being referred to as a transition destination class;

the plurality of classes include an airbag-inflating class that enables inflating of an airbag and a none-airbag-inflating class that disables inflating of the airbag;

the plurality of threshold times include (i) a third threshold time that is defined for the inter-class transition between the airbag-inflating classes;

(ii) a fifth threshold time that is defined for the inter-class transition from the airbag-inflating class into the none-airbag-inflating class; and

(iii) a sixth threshold time that is defined for the inter-class transition from the none-airbag-inflating class into the airbag-inflating class; and

the third threshold time between the airbag-inflating classes is designated to be longer than the fifth threshold time from the airbag-inflating class into the none-airbag-inflating class, whereas the fifth threshold time from the airbag-inflating class into the none-airbag-inflating class is designated to be longer than the sixth threshold time from the none-airbag-inflating class into the airbag-inflating class.