Capacitive sensor for detecting the thickness or application of an automobile brake pad
AssigneeRosemount Inc.
InventorWilliam T. Anderson
Life of this patent
Estimating the term…
Abstract
A capacitive sensor for sensing the thickness of an automobile brake pad is provided. The sensing capacitor includes a pair of parallel plates that are arranged such that brake pad wear reduces the size of one or both of the pads. The reduced size of the plate(s) is detectable as a change in capacitance between the plates. In on aspect a reference capacitor is also placed within the brake pad. The reference capacitor includes a pair of plates that do not change size during wear of the brake pad. The capacitance of the sensing capacitor can be compared to the capacitance of the reference capacitor for a more accurate indication of pad wear.
Claims13
A brake pad for an vehicle, the brake pad comprising:
- a base member;
- a pad portion disposed on the base member, the pad portion being constructed from a substantially non-conductive dielectric material;
- and
- a first pair of capacitive plates disposed in the pad portion and arranged such that wear of the pad portion changes the capacitance between the first pair of capacitive plates.
A method of determining brake pad thickness in a vehicle, the method comprising:
- measuring a capacitance between a pair of capacitive plates;
- wherein the pair of capacitive plates are disposed in a portion of the brake pad subject to wear, and
- wherein at least one of the pair of capacitive plates becomes smaller as the break pad wears, and in a manner that changes the capacitance between the pair of plates.
Dependencies are inferred from the claim text.