Patent ID: 8433476

Claim:
An apparatus for determining a seat occupancy, comprising: a load detecting portion provided at a seated portion of a seat for a vehicle and detecting a seating load applied to the seated portion; a seatbelt detecting portion detecting an engagement of a buckle of a seatbelt provided at the seat; and a seat occupancy determining portion determining that an adult is seated on the seat in a case where the seating load equal to or greater than a predetermined first load is detected by the load detecting portion and determining a child seat placed state where a child seat is placed on the seat and fastened by the seatbelt in a case where the seating load smaller than the predetermined first load is detected by the load detecting portion and the engagement of the buckle of the seatbelt is detected by the seatbelt detecting portion, the seat occupancy determining portion maintaining a determination result of the child seat placed state even when the seating load becomes equal to or greater than the predetermined first load in a case where a predetermined determination result retention condition is satisfied after the child seat placed state is determined; wherein the seat occupancy determining portion determines that the adult is seated on the seat in a case where the adult is not determined to be seated on the seat within a set time from a detection of a disengagement of the buckle of the seatbelt by the seatbelt detecting portion and thereafter the load detecting portion detects that the seating load equal to or greater than the predetermined first load is maintained for a predetermined second time; wherein the seat occupancy determining portion determines that the adult is seated on the seat in a case where the adult is not determined to be seated on the seat within the set time from the detection of the disengagement of the buckle of the seatbelt by the seatbelt detecting portion and thereafter the load detecting portion detects that the seating load equal to or greater than a predetermined second load that is larger than the predetermined first load is maintained for a predetermined third time that is shorter than the second time regardless of whether or not the seating load equal to or greater than the predetermined first load is maintained for the second time.