COMPRESSIVE VILLARI EFFECT SEATBELT TENSION SENSOR

• US 20020011123A1
• Filed: 12/30/1998
• Published: 01/31/2002
• Est. Priority Date: 01/02/1998
• Status: Active Grant

• Current Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: OʼBOYLE, MICHAEL E.
• Granted Patent: US 6,363,793 B2
• Time in Patent Office: Days
• US Class Current: 73/862.391
• CPC Class Codes: B60R 21/0155 sensing belt tension
• CPC Class Codes: G01L 5/10 using electrical means
• CPC Class Codes: G01L 5/102 using sensors located at a non-interrupted part of the flexible member
• CPC Class Codes: G01L 5/103 using sensors fixed at one end of the flexible member
• CPC Class Codes: G01L 5/108 for measuring a reaction force applied on a single support, e.g. a glider

Abstract

A Villari effect seatbelt tension sensor 10 comprises a sensor housing 30 having a sensor chamber 32 therein. A first end 34 of the sensor housing 30 has a plurality of pull rod holes 36 therein for acceptance of a plurality of pull rods 60. A Villari effect sensor 20 comprising a magnetostrictive sensor rod 22 is disposed axially within the sensor chamber 32 and abuts the first end 34 of the sensor housing 30. A plunger 40 is disposed within the sensor chamber 32 and is slidably movable therein. One end of the pull rods 60 is secured to the plunger 40. A spring 50 is disposed between the plunger 40 and a second end 26 of the sensor rod 22 to bias the sensor rod 22 toward the first end 34 of the sensor housing 30.

Claims

1. A seatbelt tension sensor comprising:

a sensor housing having a sensor chamber therein, a first end having a plurality of pull rod holes therein, and a seatbelt orifice opposite the first end for acceptance of said seatbelt;

an axially movable plunger disposed within the sensor chamber;

a plurality of pull rods extending through the pull rod holes of said sensor housing secured at a first end to said plunger and secured at a second end to a pull rod head having a mounting hole therein;

a Villari effect sensor disposed axially within the sensor chamber having a first end abutting the first end of said sensor housing, and;

a spring disposed between said Villari effect sensor and said plunger for biasing said Villari effect sensor towards said sensor housing first end.

2. The seatbelt tension sensor as claimed in claim 1 wherein said sensor housing further comprises an inwardly extending radial flange disposed therein to prevent said plunger from traveling past said flange in the event of breakage of said Villari effect sensor.

3. The seatbelt tension sensor as claimed in claim 1 wherein said Villari effect sensor generates an output responsive to a compressive force acting thereon.

4. The seatbelt tension sensor as claimed in claim 1 wherein said Villari effect sensor rod is comprised of a magnetostrictive material having a positive magnetostrictive coefficient.

5. The seatbelt tension sensor as claimed in claim 2 wherein said Villari effect sensor generates an output responsive to a compressive force acting thereon.

6. The seatbelt tension sensor as claimed in claim 2 wherein said Villari effect sensor rod is comprised of a magnetostrictive material having a positive magnetostrictive coefficient.