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US 9,857,244 B2Granted
In-cylinder pressure measurement utilizing a magneto-elastic element for measuring a force exerted on an engine valve assembly
AssigneeEaton Corporation
InventorsMark Allan Juds, John Albert Kovacich
Life of this patent
Estimating the term…
Abstract
A force sensor can include a magnetic field generator, a magnetic flux return, and a magneto-elastic layer. The magnetic flux return can extend along a first portion of at least one pathway of magnetic flux generated by the magnetic field generator. The magneto-elastic layer can be operable to be in contact with a surface subjected to force and thereby strained. The magneto-elastic layer can extend along a second portion of the at least one pathway of magnetic flux distinct from the first portion.
Claims22
An apparatus for measuring pressure within a cylinder of an internal combustion engine, comprising:
- an engine valve assembly having a valve for reciprocating in a combustion chamber of the internal combustion engine, the valve having a valve head and a valve stem, the valve head having a valve face configured to be in pressure communication with a valve seat of the combustion chamber;
- and
- a force sensor comprising:
- a magnetic field generator;
- a magnetic flux return extending along a first portion of at least one pathway of magnetic flux generated by the magnetic field generator;
- and
- a magneto-elastic layer operable to be in contact with a surface of the engine valve assembly subjected to force and thereby strained, the magneto-elastic layer extending along a second portion of the at least one pathway of magnetic flux distinct from the first portion, wherein the magneto-elastic layer is configured to be disposed on at least one of the valve head and the valve seat.
4 more elements
A force sensor comprising:
- a magnetic field generator;
- a magnetic flux return extending along a first portion of at least one pathway of magnetic flux generated by the magnetic field generator;
- a magneto-elastic layer operable to be in contact with a surface of a combustion engine valve assembly subjected to force and thereby strained, the magneto-elastic layer extending along a second portion of the at least one pathway of magnetic flux distinct from the first portion;
- and
- a magnetic sensor disposed at a first edge of both the magneto-elastic layer and the magnetic flux return,
- wherein the magnetic field generator is further defined as a permanent magnet disposed along the at least one pathway at a second edge of both the magneto-elastic layer and the magnetic flux return that is opposite the first edge and the magnetic sensor,
- wherein the permanent magnet has a first pole facing the magneto-elastic layer and a second pole facing the magnetic flux return.
4 more elements
A force sensor comprising:
- a magnetic field generator;
- a magnetic flux return extending along a first portion of at least one pathway of magnetic flux generated by the magnetic field generator;
- a magneto-elastic layer operable to be in contact with a surface of a combustion engine valve assembly subjected to force and thereby strained, the magneto-elastic layer extending along a second portion of the at least one pathway of magnetic flux distinct from the first portion;
- a bobbin disposed at least partially about the magnetic flux return;
- and
- a passive coil disposed about the bobbin and along the pathway of the magnetic flux;
- wherein the magnetic field generator is further defined as a permanent magnet extending between opposed first and second sides of the magnetic flux return, the permanent magnet having a first pole facing the first side of the magnetic flux return and a second pole facing the second side of the magnetic flux return,
- wherein the permanent magnet is disposed between the magneto-elastic layer and the passive coil, and
- wherein an air gap is defined between the first and second sides of the magnetic flux return and between opposed portions of the bobbin.
6 more elements
A force sensor comprising:
- a magnetic field generator;
- a magnetic flux return extending along a first portion of at least one pathway of magnetic flux generated by the magnetic field generator;
- a magneto-elastic layer operable to be in contact with a surface of a combustion engine valve assembly subjected to force and thereby strained, the magneto-elastic layer extending along a second portion of the at least one pathway of magnetic flux distinct from the first portion;
- and
- a magnetic sensor disposed in a balancing air gap defined between opposed first and second sides of the magnetic flux return,
- wherein the magnetic field generator is further defined as a permanent magnet extending between opposed first and second sides of the magnetic flux return, the permanent magnet having a first pole facing the first side of the magnetic flux return and a second pole facing the second side of the magnetic flux return, and
- wherein the permanent magnet is disposed between the magneto-elastic layer and the magnetic sensor.
4 more elements
Dependencies are inferred from the claim text.