CAPACITANCE-TYPE OCCUPANT DETECTION SENSOR

• US 20130328577A1
• Filed: 05/15/2013
• Published: 12/12/2013
• Est. Priority Date: 06/07/2012
• Status: Abandoned Application

• Current Assignee: DENSO Corporation, Nippon Soken, Inc. (DENSO Corporation)
• Original Assignee: DENSO Corporation, Nippon Soken, Inc. (DENSO Corporation)
• Inventors: Satake, Masayoshi, Mori, Hiroyuki, Nakagawa, Hajime
• Application Number:
  US13/894,745
• Publication Number:
  US 20130328577A1
• Time in Patent Office: Days
• US Class Current: 324/688
• CPC Class Codes: B60R 21/01532 using electric or capacitive field sensors
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24

Abstract

A capacitance-type occupant detection sensor of the present disclosure detects a vehicle occupant on a seat based on a difference of capacitance between a sensor body and a reference electric potential. The sensor body includes a main electrode and a parallel electrode. The parallel electrode is disposed in parallel with the main electrode with a gap interposed therebetween and has a detection voltage applied thereto. The main electrode and the parallel electrode each have a base material, a first electrode member disposed on the base material, and a second electrode member disposed on the base material to cover the first electrode member, where the second electrode member has an electric conductivity that is lower than the first electrode member. The first electrode member is disposed on a lateral perimeter of the second electrode member to surround a center of the second electrode member.

Claims

1. A sensor body of a capacitance-type occupant detection sensor for detecting an occupant seated on a seat of a vehicle based on a capacitance value between a reference voltage and the sensor body, the sensor body being disposed in the seat, the sensor body comprising:

a main electrode having a detection voltage applied thereto; and

a parallel electrode disposed in parallel with the main electrode with a gap interposed therebetween, the parallel electrode having the detection voltage applied thereto, wherein

the main electrode and the parallel electrode each have a base material, a first electrode member disposed on the base material, and a second electrode member disposed on the base material to cover the first electrode member, the second electrode member has an electric conductivity lower than the first electrode member, and

the first electrode member is disposed on a lateral perimeter of the second electrode member to surround a center of the second electrode member.

2. A sensor body of a capacitance-type occupant detection sensor for detecting an occupant seated on a seat of a vehicle based on a capacitance value between a reference voltage and the sensor body, the sensor body being disposed in the seat, the sensor body comprising:

a main electrode having a detection voltage applied thereto, the main electrode having a loop portion and a non-loop portion, the loop portion having a terminating end connected to the main electrode, and the non-loop portion extending from the loop portion;

a parallel electrode disposed in parallel with the main electrode with a gap interposed therebetween, the parallel electrode having the detection voltage applied thereto, wherein the parallel electrode is disposed along a first lateral side of the loop portion, and has a starting end and a terminating end positioned on both sides of the non-loop portion; and

a guard electrode arranged to face the main electrode and having a same voltage applied thereto as the detection voltage, the guard electrode having a facing part and a protrusion part, wherein the facing part faces the main electrode and the protrusion part extends from the facing part in a direction away from the parallel electrode, such that the protrusion part extends towards a second lateral side of the loop portion, which is opposite of the first lateral side of the loop portion.

3. A capacitance-type occupant detection sensor comprising:

a sensor body disposed in a seat of a vehicle and including;

a main electrode having a detection voltage applied thereto,

a parallel electrode disposed in parallel with the main electrode with a gap interposed therebetween, the parallel electrode having the detection voltage applied thereto, and

a guard electrode having a facing part and a sub-guard part, the facing part arranged to face the main electrode, the sub-guard part disposed between the main electrode and the parallel electrode, and the facing part and the sub-guard part having a same voltage applied thereto as the detection voltage; and

a detection part detecting an occupant on the seat based on a capacitance value between the main electrode and a reference electrode, wherein the detection part detects a liquid spill on the seat based on a capacitance between the main electrode and the parallel electrode when a predetermined voltage is applied to the parallel electrode.