Torsional sensing load cell
AssigneeGagetek Technologies Holdings Company
InventorRobert W. Bruns
Life of this patent
Estimating the term…
Abstract
A torsional sensing load cell, particularly for mounting at support locations of an automotive seat in order to determine weight and sitting position of an occupant of a motor vehicle. The load cell has the shape of a tuning fork, with one arm fixed to a foot attached to a chassis and a second parallel arm, not contacting the first arm, arranged to support a quadrant of a seat by means of a flange on the side of the second arm, causing torsion in the arm. The two arms are connected at one end by means of a bridge section through which torsion is transmitted arising from twisting in the second arm. Torsion is measured by transducers on the bridge section with torsion signals converted to weight signals. The weight signals are used to control deployment of an air bag or other safety apparatus.
Claims28
A load cell for use as a force indicator comprising:
- a first linear arm held in a relatively fixed position,
- a second linear arm, parallel to the first arm, connected to a load associated with a force,
- a joining section, connecting the first and second arms, transmitting torsion between the first and second arms, and
- a force transducer connected to produce an electrical output signal representing torsion between the first and second arms, and
- an electrical circuit connected to receive said output signal representing torsion and to use said signal to indicate the load associated with a force.
A force sensing device for a movably adjustable seat comprising:
- a seat,
- four feet anchored to a rigid platform in a rectangular pattern corresponding in location to four imaginary legs of the seat,
- a pair of parallel, spaced apart rail assemblies having inner and outer parallel telescoping rails, one of the inner and outer rails fixed to opposite lateral sides of the seat,
- four torsional sensing load cells, one load cell associated with each post, each load cell having spaced apart first and second arms in a torsional relation through a joining section, with a first arm connected to a post, each load cell having a transducer converting torsion to an electrical signal representative of force on the seat,
- the other of the inner and outer parallel rails, located at least partially within the one rail with a second arm of each load cell fixedly connected to the fixed rail wherein the fixed rail is supported between two feet by a pair of said torsional sensing load cells,
- whereby force on the seat is transferred between rails and the feet through the torsional sensing load cells, producing four electrical signals indicative of the force on the seat.
A method of making a torsional strain gauge comprising:
- forming a beam into a shape having a curved section, with opposed segments of the beam forming ends of the curved section in torsional capability toward each other,
- printing strain gauges on the opposed segments of the beam.
A method of weighing a seated person,
- supporting a seat with torsional sensing load cells mounted to a seat support structure,
- developing electrical load signals representing torsion on the torsional load sensors from a person seated on the seat, and converting the load signals to a signal proportional to weight.
Dependencies are inferred from the claim text.