Villari effect seatbelt tension sensor

• US 6,336,371 B1
• Filed: 11/19/1998
• Issued: 01/08/2002
• Est. Priority Date: 01/09/1997
• Status: Expired due to Fees

• 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.
• Primary Examiner(s): Fuller, Benjamin R.
• Assistant Examiner(s): DAVIS, OCTAVIA L
• Application Number:
  US09/196,093
• Time in Patent Office: 1,146 Days
• Field of Search: 738/659, 738/626.9, 738/623.31, 738/623.91, 738/623.36, 280/735, 280/806, 340/457.1, 340/43.B
• US Class Current: 73/865.9
• CPC Class Codes: B60R 2021/01317 monitoring seat belt tensiont
• CPC Class Codes: B60R 21/015 including means for detecting the presence or position of passengers, passenger seats or child seats , and the related safety parameters therefor, e.g. speed or timing of airbag inflation in relation to occupant position or seat belt use
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: B60R 21/0155 sensing belt tension
• CPC Class Codes: B60R 21/01556 Child-seat detection systems
• CPC Class Codes: B60R 22/18 Anchoring devices
• 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
• CPC Class Codes: G01L 1/125 by using magnetostrictive means magnetostrictive sensors H10N35/101
• 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 50 having a plunger chamber 52 and a tongue head flange chamber 54 therein. The two chambers 52 and 54 are separated by a radial flange 58 extending therebetween defining a passage connecting the chambers. A Villari effect sensor 12 is disposed axially within the sensor housing 50 and is secured on one end 16 to a plunger 40 disposed within the plunger chamber 52 and secured on the opposite end 14 to a tongue head flange 20 disposed within the tongue head flange chamber 54. A tongue 24 connected by a shaft 28 to the tongue head flange 20 has a slot 26 therein for securing a seatbelt 80 thereto.

Claims

1. A seatbelt tension sensor comprising:

a sensor housing having a plunger chamber and a tongue head chamber therein connected by a passage defined by a radial flange extending inwardly therebetween, said sensor housing further having a mounting bolt hole on a one end thereof, and a housing lip on an opposed end thereof defining a passage therein;

a plunger having an anchor hole therein, said plunger disposed within said sensor housing plunger chamber;

a tongue head flange disposed within the tongue head chamber having an anchor hole therein and a tongue shaft extending axially therefrom through the passage defined by the housing lip of said sensor housing;

a tongue extending from the tongue shaft having a slot therein for securing said seatbelt thereto;

a Villari effect sensor comprising an axially disposed magnetostrictive material having first and second ends, said first and second ends having respective first and second anchors secured thereto, wherein said first anchor is disposed in the anchor hole of said plunger and said second anchor is disposed in the anchor hole of said tongue head flange; and

a spring having a first end and a second end, said spring disposed coaxially about said Villari effect sensor, wherein the first end of said spring abuts said plunger and the second end of said spring abuts said sensor housing radial flange.

2. The seatbelt tension sensor as claimed in claim 1 wherein said Villari effect sensor anchors are comprised of a nonmetallic material.

3. The seatbelt tension sensor as claimed in claim 1 wherein said Villari effect sensor magnetostrictive material has a negative magnetostrictive coefficient.

4. The seatbelt tension sensor as claimed in claim 1 wherein said Villari effect sensor magnetostrictive material is comprised of nickel.

5. A seatbelt tension sensor comprising:

a sensor housing having a plunger chamber and a tongue head chamber therein connected by a passage defined by a radial flange extending inwardly therebetween, said sensor housing further having a first end and a second end, said first end having a mounting bolt hole therein, and a housing lip disposed on the second end defining a passage therein;

a plunger disposed within said sensor housing plunger chamber;

a tongue head flange disposed within the tongue head chamber having a tongue shaft extending axially therefrom through the passage defined by the housing lip of said sensor housing;

a tongue extending from the tongue shaft having a slot therein for securing said seatbelt thereto;

a Villari effect sensor comprising an axially disposed magnetostrictive material having first and seconds ends secured to said plunger and said tongue head flange respectively; and

a spring having a first and a second end, said spring disposed coaxially about said Villari effect sensor, wherein the first end of said spring abuts said plunger and the second end of said spring abuts said sensor housing radial flange.

6. The seatbelt tension sensor as claimed in claim 5 wherein said Villari effect sensor magnetostrictive material has a negative magnetostrictive coefficient.

7. The seatbelt tension sensor as claimed in claim 5 wherein said Villari effect sensor magnetostrictive material is comprised of nickel.