Frame-based occupant weight estimation apparatus having compliant load transfer mechanism

• US 7,308,347 B2
• Filed: 07/14/2003
• Issued: 12/11/2007
• Est. Priority Date: 07/14/2003
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG (Aptiv PLC)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Murphy, Morgan D.
• Primary Examiner(s): To; Tuan C
• Application Number:
  US10/618,952
• Publication Number:
  US 20050027418A1
• Time in Patent Office: 1,611 Days
• Field of Search: 701/45, 701/46, 701/47, 701/36, 280/728.1, 280/735, 296/65.01, 177/144, 177/170, 177/176, 177/154, 73/11.3, 738/626.27, 738/626.28, 180/273, 340/667, 340/666
• US Class Current: 701/45
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: B60R 21/0152 using strain gauges
• 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

Abstract

A frame-based occupant weight estimation apparatus for a vehicle seat includes compliant load transfer mechanisms interposed between the seat frame and floor brackets bolted to the vehicle floor. The compliant load transfer mechanisms translate the seat loads to a central location for measurement by a set of force sensors. The load transfer mechanisms preload the force sensor to enable off-loading detection, and an overload device securely anchors the seat to the floor bracket without interfering with normal load measurement.

Claims

1. Apparatus for estimating the weight of an occupant of a vehicle seat supported by a floor bracket, the apparatus comprising:

a force sensor;

a compliant force transfer mechanism interposed between said floor bracket and a mounting bracket of said seat, including first and second co-joined lever arms coupled to said floor bracket and said mounting bracket, where said lever arms terminate in first and second jaws that engage said force sensor, where said jaws exert a pre-load engagement force on said force sensor, and where occupant weight applied to said seat produces movement of said lever arms that increases said engagement force, whereby said force sensor produces an output signal indicative of said occupant weight,wherein said first lever arm is rotatably coupled to said mounting bracket and said second lever arm is rigidly secured to said floor bracket, and wherein said first and second lever arms are interconnected at an active joint adjacent said jaws and a passive joint that limits relative displacement therebetween; and

overload means for limiting upward movement of said seat mounting bracket with respect to said floor bracket to prevent said seat from becoming detached from said floor bracket, said overload means including a vertically extending plate coupled to one of said brackets and spaced adjacent the other of said brackets for engagement thereof in response to a predetermined upward displacement of said seat.

2. Apparatus for estimating the weight of an occupant of a vehicle seat supported by a floor bracket, the apparatus comprising:

a force sensor; and

a compliant force transfer mechanism interposed between said floor bracket and a mounting bracket of said seat, including first and second co-joined lever arms coupled to said floor bracket and said mounting bracket, where said lever arms terminate in first and second jaws that engage said force sensor, where said jaws exert a pre-load engagement force on said force sensor, and where occupant weight applied to said seat produces movement of said lever arms that increases said engagement force, whereby said force sensor produces an output signal indicative of said occupant weight,

wherein said seat includes a set of mounting brackets,and the apparatus includes a force sensor and compliant force sensors are co-located in paris to facilitate electrical connections to the force sensors, wherein said first lever arm is rotatably coupled to said mounting bracket and said second lever arm is rigidly secured to said floor bracket, and wherein said first and second lever arms are interconnected at an active joint adjacent said jaws and a passive joint that limits relative displacement therebetween.