Patent ID: 7240571

Claim:
A load sensor adapted for mounting on an axle, the axle having a neutral axis, and the axle deviating from the neutral axis when under a load, said load sensor comprising: a reaction portion, said reaction portion being adapted for mounting at a point along the axle; an active portion, said active portion being adapted for mounting at at least two points along said axle, said active portion having an amplifier arm; at least one sensor element, said sensor element being attached at a first end to said reaction portion and said sensor element being attached to the second end to said amplifier arm; at least one strain gauge mounted on said sensor element; at least one flexion web, said flexion web being attached to said reaction portion and said flexion web being attached to said active portion; wherein, when a load is put on the axle, flexion of the axle moves said active portion relative to the neutral axis of the axle, said active portion moves said amplifier arm, causing a curve to be formed in said sensor element, said curve being of sufficient magnitude to be calibrated by said at least one strain gauge, and wherein said at least one flexion web defines a slot between said at least one flexion web and said amplifier arm, each of said first and second flexible web extending beyond said first and second slot to a length substantially coextensive with said at least one sensor element.