Frame-based bladder apparatus for seat occupant weight estimation

• US 20040262048A1
• Filed: 06/27/2003
• Published: 12/30/2004
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Tieman, Craig A., Murphy, Morgan D., Fortune, Duane D., McKinley, James R.
• Granted Patent: US 7,059,446 B2
• Time in Patent Office: Days
• US Class Current: 177/144
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0025 by using weight measurement
• CPC Class Codes: B60N 2/0031 mounted on the frame
• CPC Class Codes: B60N 2210/44 using fluids
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• 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 that is supported by two or more floor brackets secured to the vehicle floor spans an open space between the floor brackets to prevent shunting of the occupant weight through a foreign object lying on the floor between the floor brackets. The weight estimation apparatus includes a fluid filled bladder sandwiched between first and second rigid plates, and is held in place between the seat frame and the floor brackets by a set of fasteners. A spring preloads the bladder so that deviations of the bladder fluid pressure from the preload pressure will be indicative of occupant weight. The first plate spans the open space between the floor brackets so that the fluid pressure is indicative of occupant weight even in cases where a portion of the occupant weight is supported by a foreign object disposed between the floor brackets.

Claims

1. Apparatus for estimating the weight of an occupant of a vehicle seat supported by first and second floor brackets secured to a vehicle floor, the apparatus comprising:

a load cell including first and second rigid plates, and a fluid-filled bladder interposed between said first and second rigid plates;

fastener means for securing said load cell between a frame of said seat and said floor brackets such that said load cell spans an open space between said first and second floor brackets, said fastener means including compliant elements for preloading said bladder between said first and second plates, and substantially non-compliant elements for preventing separation of said seat from said floor brackets; and

a pressure sensor coupled to an exit port of said bladder for sensing a pressure of the fluid in said bladder that provides an indication of the weight of the occupant.

2. The apparatus of claim 1, wherein said compliant elements are springs or foam pads interposed between said seat and said load cell.

3. The apparatus of claim 1, wherein said compliant elements are springs or foam pads interposed between said floor brackets and said load cell.

4. The apparatus of claim 1, wherein said non-compliant elements are bolts passing through apertures in said load cell.