Patent ID: 7663378

Claim:
A passenger seat device for an automotive vehicle, comprising: a seat heater embedded in a seat in parallel to a seat surface, electric current being supplied to the seat heater in a controlled manner from an on-board power source; a detector electrode embedded in the seat above the seat heater in parallel thereto; an alternating current power source for supplying an alternating voltage having a predetermined frequency to the detector electrode; and a detector for detecting occupancy conditions of the seat based on changes in an equivalent impedance coupled to the detector electrode, wherein: the seat surface is covered with a water-permeable cover; the seat heater is protected with a waterproof sheet to prevent water permeated from the seat surface from reaching the seat heater; and a shielding electrode positioned between the detector electrode and the seat heater substantially in parallel thereto and an insulating film positioned between the detector electrode and the shielding electrode in parallel thereto, wherein the insulating film also functions as the waterproof sheet.