Land vehicles – Wheeled – Attachment
Reexamination Certificate
2001-10-05
2002-12-17
Dickson, Paul N. (Department: 3616)
Land vehicles
Wheeled
Attachment
C180S273000, C073S853000, C073S862629, C177S211000
Reexamination Certificate
active
06494482
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus for measuring the weight of a seat occupant. Specifically, a sensor arrangement is mounted to a seat frame member to provide seat occupant weight measurements.
2. Related Art
Most vehicles include airbags and seatbelt restraint systems that work together to protect the driver and passengers from experiencing serious injuries due to a high speed collision. It is important to control the deployment force of the airbags and the force of the seatbelt pre-tensioners based on the size of the driver or the passenger. One way to control these forces is to monitor the weight of the seat occupant. If a smaller person such as a child or infant in a car seat is in the front passenger seat, the weight on the seat will be less than if an adult occupies the seat.
Current systems for measuring the weight of a seat occupant are complex and expensive. One type of system uses pressure sensitive foil mats mounted within the seat bottom foam. Another system uses sensors placed at a plurality of locations within the seat bottom cushion. The combined output from the mats or the sensors is used to determine the weight of the seat occupant. These sensors experience a substantially vertical force, due to the weight of the seat occupant, but are also subject to longitudinal and lateral forces caused by acceleration, deceleration, or turning. The lateral and longitudinal forces picked up by the sensor incorporate an error component into the weight measurement. The sensors are very sophisticated using multiple strain gages and complicated bending elements to provide high measurement sensitivity in the vertical direction and low sensitivity to lateral and longitudinal forces in order to increase accuracy.
Mounting these sensors within the seat bottom can also be difficult and time consuming. It is difficult to find mounting locations for each the sensors that will accommodate all of the various positions of a seated occupant while still providing accurate measurements. Further, shifting of the occupant on the seat can dislodge or move the sensors out of their proper location. Because the sensors are mounted within the seat bottom, it is difficult to reposition the sensors after the seat is installed in the vehicle.
Thus, it is desirable to have a simplified seat occupant weight measurement system that is accurate and easily to install and overcomes the above references deficiencies with prior art systems.
SUMMARY OF THE INVENTION
In a disclosed embodiment of this invention, a system for measuring the weight of an occupant seated on a vehicle seat includes a seat element mounted to a vehicle structure and a seat support member for supporting a seat bottom. A plurality of weight sensor assemblies are mounted between the seat element and the seat support member. Each of the weight sensor assemblies has a bottom surface and a top surface with a full bridge strain gage mounted on one of the surfaces.
In a preferred embodiment, each weight sensor assembly has a first end mounted to the seat element, such as a seat riser, and a second end mounted to the seat support member, such as a seat frame or track member, with a central bendable portion extending between the first and second ends. The strain gages each generate a weight signal in response to measuring deflection of the central bendable portion for the respective sensor assembly. A central processor determines the seat occupant weight based on the weight signals. An airbag control module communicates with the processor to control deployment force of an airbag based on seat occupant weight.
In a further preferred embodiment, each of the sensors includes at least one groove formed in one of the top or bottom surfaces. The groove extends at least partially along the width of the sensor to localize strain in the central bendable portion. The strain gage is placed on the other of the top or bottom surfaces, facing opposite from the groove.
The subject invention provides a simplified seat occupant weight measurement system that is inexpensive, accurate, and easily to install. These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
REFERENCES:
patent: 2708005 (1955-05-01), Gazzo
patent: 3022976 (1962-02-01), Zia
patent: 3766344 (1973-10-01), Nevett
patent: 4075443 (1978-02-01), Fatur
patent: 4181012 (1980-01-01), Kiuchi
patent: 4558757 (1985-12-01), Mori et al.
patent: 5232243 (1993-08-01), Blackburn et al.
patent: 5413378 (1995-05-01), Steffens, Jr. et al.
patent: 5474327 (1995-12-01), Schousek
patent: 5481078 (1996-01-01), Asche
patent: 5502284 (1996-03-01), Meiller et al.
patent: 5542493 (1996-08-01), Jacobson et al.
patent: 5570903 (1996-11-01), Meister et al.
patent: 5573269 (1996-11-01), Gentry et al.
patent: 5605348 (1997-02-01), Blackburn et al.
patent: 5612876 (1997-03-01), Zeidler et al.
patent: 5618056 (1997-04-01), Schoos et al.
patent: 5626359 (1997-05-01), Steffens, Jr. et al.
patent: 5670853 (1997-09-01), Bauer
patent: 5678854 (1997-10-01), Meister et al.
patent: 5732375 (1998-03-01), Cashler
patent: 5739757 (1998-04-01), Gioutsos
patent: 5804887 (1998-09-01), Holzapfel et al.
patent: 5810392 (1998-09-01), Gagnon
patent: 5942695 (1999-08-01), Verma et al.
patent: 5971432 (1999-10-01), Gagnon et al.
patent: 6005199 (1999-12-01), Harada et al.
patent: 6039344 (2000-03-01), Mehney et al.
patent: 6069325 (2000-05-01), Aoki
patent: 6070115 (2000-05-01), Oestreicher et al.
patent: 6092838 (2000-07-01), Walker
patent: 6161891 (2000-12-01), Blakesley
patent: 6250671 (2001-06-01), Osmer et al.
patent: 38 09 074 (1992-03-01), None
patent: 197 52 356 (1999-05-01), None
patent: 199 31 379 (2001-01-01), None
patent: 0 534 226 (1996-12-01), None
patent: 0 962 362 (1999-12-01), None
patent: 0 990 565 (2000-04-01), None
patent: 9 150662 (1997-06-01), None
patent: 0100454 (2001-01-01), None
Research Disclosure, Jul. 1997, No. 399, p. 442.
International Search Report, Aug. 2000. PCT/US 00/17237.
Dickson Paul N.
Dunn David R.
Siemens VDO Automotive Corporation
LandOfFree
Weight sensor assembly for determining seat occupant weight does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Weight sensor assembly for determining seat occupant weight, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Weight sensor assembly for determining seat occupant weight will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2924009