State sensor systems and methods

Patent metadata

Field	Value
Publication number	US-9366549-B2
Application number	US-201414248752-A
Country	US
Kind code	B2
Filing date	Apr 9, 2014
Priority date	Apr 9, 2014
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

Sensor systems comprising a magnetic circuit comprising a coil, a magnet, at least one of a ferromagnetic armature plate and a conductive armature plate, wherein the at least one of the ferromagnetic armature plate and the conductive armature plate is configured to move axially in response to at least one of the magnet and the coil, and a controller configured to apply a known first voltage across the coil and monitor a current through the coil are provided. Methods are also provided.

First claim

What is claimed is:

1. A sensor system comprising:
a magnetic circuit comprising a coil;
a magnet;
at least one of a ferromagnetic armature plate and a conductive armature plate, wherein the at least one of the ferromagnetic armature plate and the conductive armature plate is configured to move axially in response to at least one of the magnet and the coil; and
a controller configured to apply a known first voltage across the coil and monitor a current through the coil;
an inner pole; and
an outer pole, wherein the coil is in proximity to at least one of the inner pole and the outer pole, and the magnet is disposed between a first portion of the inner pole and a first portion of the outer pole, and the at least one of the ferromagnetic armature plate and the conductive armature plate is disposed in axial proximity to a second portion of the inner pole and a second portion of the outer pole, forming the magnetic circuit, wherein the ferromagnetic armature plate is configured to move axially.

2. The sensor system of claim 1 , wherein the known first voltage has a frequency between about 500 Hz and 15 kHz.

3. The sensor system of claim 2 , wherein the controller is configured to provide the known first voltage via pulse-width modulation.

4. The sensor system of claim 2 , wherein the controller is configured to apply a known second voltage, wherein the known second voltage comprises a frequency that is different than the known first voltage.

5. The sensor system of claim 1 , wherein the controller is configured to detect a change in an eddy current.

6. The sensor system of claim 1 , wherein the controller is configured to determine an inductive reactance.

7. The sensor system of claim 1 , wherein the coil surrounds at least a part of the inner pole.

8. A friction brake assembly comprising the sensor system of claim 1 .

9. The sensor system of claim 1 , wherein the controller is an electromechanical actuator controller (“EMAC”) and is configured to determine an axial position of the at least one of the ferromagnetic armature plate and the conductive armature plate.

10. The method of claim 1 , wherein the controller is configured to determine an axial height of a dynamic gap between the at least one of a ferromagnetic armature plate and a conductive armature plate and at least one of an inner pole, an outer pole or a magnet.

11. The method of claim 8 , wherein the controller is configured to determine an axial height of a dynamic gap between the at least one of a ferromagnetic armature plate and a conductive armature plate and at least one of an inner pole, an outer pole or a magnet.

12. A method comprising:
applying a known first voltage via a controller coupled to a coil forming part of a magnetic circuit, wherein the magnetic circuit comprises:
a magnet and at least one of a ferromagnetic armature plate and a conductive armature plate configured to move axially;
an inner pole; and
an outer pole, wherein the coil is in proximity to at least one of the inner pole and the outer pole, and the magnet is disposed between a first portion of the inner pole and a first portion of the outer pole, and the at least one of the ferromagnetic armature plate and the conductive armature plate is disposed in axial proximity to a second portion of the inner pole and a second portion of the outer pole:
monitoring the known first voltage across the coil;
monitoring a first current response through the coil; and
determining a phase lag between the known first voltage and the first current response.

13. The method of claim 12 , further comprising determining an inductive reactance based on the phase lag between the known first voltage and the first current response.

14. The method of claim 12 , wherein the known first voltage has a frequency between about 500 Hz and 15 kHz.

15. The method of claim 12 , wherein the determining the phase lag between the known first voltage and the first current response comprises detecting a change in an eddy current.

16. The method of claim 12 , further comprising determining a state of a friction brake assembly.

17. The method of claim 12 , further comprising determining an axial height of a dynamic gap between the at least one of a ferromagnetic armature plate and a conductive armature plate and at least one of an inner pole, an outer pole or a magnet.

Assignees

• Goodrich Corp

Inventors

• Slanker Andrew Joseph
• Summers Herbert S
• Beason Joseph E

Classifications

• G01R31/72

  Testing of electric windings (testing of transformers G01R31/62) · CPC title

• G01D5/2013 Primary

  by a movable ferromagnetic element, e.g. a core (G01D5/2033 takes precedence) · CPC title

• B60T17/221

  Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems (hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M) · CPC title

• F16D2066/003

  Position, angle or speed · CPC title

• B60T17/18

  Safety devices; Monitoring · CPC title