Method and system for exhaust particulate matter sensing
AssigneeFord Global Technologies, LLC
InventorXiaogang Zhang
Life of this patent
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Abstract
Methods and systems are provided for sensing particulate matter by a particulate matter (PM) sensor positioned upstream, or downstream, of a diesel particulate filter in an exhaust system. The PM sensor may include first and second conductive matrixes each having a three dimensional shape. The first matrix functions as a positive electrode, and the second functions as a negative electrode. Each matrix defines extensions and/or passages passing respectively through, and/or near, each other to form multiple soot capturing gaps. A first of the multiple soot capturing gaps is oriented orthogonal to a second of the multiple soot capturing gaps.
Claims13
A particulate matter sensor, comprising
- a first conductive matrix having a three-dimensional shape defined by an x-dimension, a y-dimension, and a z-dimension to be charged to a first voltage to function as a positive electrode;
- a second conductive matrix having a three-dimensional shape defined by the x-dimension, the y-dimension, and the z-dimension to be charged to a second voltage to function as a negative electrode;
- and
- one of the first and second matrixes defining extensions and/or passages, and the other of the first and second matrixes defining extensions and/or passages, the extensions and/or the passages passing respectively through and/or spaced from each other forming multiple soot capturing gaps defined by a local shortest distance from the first matrix to the second matrix, and wherein a first of the multiple soot capturing gaps is oriented orthogonal to a second of the multiple soot capturing gaps;
- and
- wherein a change in voltage of the first and/or second matrix is effected by soot forming in the soot capturing gaps and is determinable as a soot concentration level in an exhaust stream from an engine.
A particulate matter (PM) sensor for use in an engine exhaust comprising:
- a positive electrode having multiple extensions and/or multiple passages;
- and
- a negative electrode having multiple extensions and/or multiple passages;
- wherein the passages and the extensions pass respectively through and/or spaced from each other forming multiple soot capturing gaps between the positive electrode and the negative electrode, each soot capturing gap having an orientation defined by a local shortest distance between the positive electrode and the negative electrode, wherein a first portion of the soot capturing gaps are orientated substantially orthogonally to a second portion of soot capturing electrodes.
Dependencies are inferred from the claim text.