US 2015/0177338 A1 · DLA ROTOR FLUX DENSITY SCAN METHOD AND TOOL

Abstract

A method of measuring flux density and run out to accommodate rotors of different diameters, evaluate intrinsic properties of magnet material and the magnetization process. Circular run out measurement capability is also used to evaluate bearing journal “ovality.” The method includes the use of a scan tool, or a DLA Rotor Flux Density Scan Fixture, which evaluates the electromagnetic field strength (gauss), combined with surface run out and presents the data in a scalable pictorial format. The scan tool includes a probe which measures a magnetic field strength and circular run out of the perimeter of the magnet. Simultaneously, a non-contact measurement sensor is used to measure the rotor surface for subtle variations. The resulting sine wave gauss data and the surface dimension data are manipulated into a scalable “radar” plot. The radar plot correlates magnetic pole field strength and surface circular run out variation to the index position.

Claims17

Dependent claims

A method for measuring the magnetic flux and run out of a surface, comprising the steps of:

providing a digital linear actuator (DLA);
providing a rotor, the rotor being part of the DLA;
providing a magnet connected to and circumscribing the rotor, the magnet having an outer surface;
providing a plot having the magnet flux density of the magnet, and the run out of the magnet;
simultaneously measuring the run out and the magnet flux density of the rotor;
and
plotting the run out and the magnet flux density are together on the plot to correlate the measurements of the run out and the magnet flux density.

4 more elements

A method for measuring the magnetic flux and run out of a surface, comprising the steps of:

providing a digital linear actuator (DLA);
providing a rotor, the rotor being part of the DLA;
providing a magnet connected to and circumscribing the rotor, the magnet having an outer surface;
providing a non-contact measurement sensor for measuring the run out on the outer surface of the magnet;
providing a gauss probe for measuring the magnet flux density on the outer surface of the magnet;
simultaneously measuring the run out and the magnet flux density;
and
plotting the run out and the magnet flux density on a plot to correlate the measurements of the run out and the magnet flux density.

5 more elements

A scan tool for measuring the magnetic flux and run out of a surface, comprising:

an indexing rotary head;
a shaft connected to and driven by the indexing rotary head;
an angular encoder for measuring the angular rotation of the shaft;
a fixture connected to and driven by the shaft, a rotor selectively mounted in the fixture;
a non-contact measurement sensor for measuring the run out on the rotor;
and
a gauss probe for measuring the flux density of the rotor;
a plot showing the measurements of the run out and the flux density;
wherein the non-contact measurement sensor measures the run out and the gauss probe simultaneously measures the flux density as the rotor is rotated in the fixture, such that measurements of both the run out and the flux density are viewable on the plot.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application

14/622,101Filed 13 Feb 2015

Priority

22 Dec 2011

Published

25 Jun 2015

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

G01R 33/038
Measuring direction or magnitude of magnetic fields or magnetic flux: using permanent magnets, e.g. balances, torsion devices
G01B 7/30
Measuring arrangements characterised by the use of electric or magnetic techniques: for measuring angles or tapers; for testing the alignment of axes
G01R 31/34
Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by…
G01R 33/0035
Electronic aspects, e.g. circuits for stimulation, evaluation, control; Treating the measured signals; calibration: calibration of single magnetic…

Family

Application61/579,211Us provisional application · filed 22 Dec 2011

Application13/710,560Continuation · filed 11 Dec 2012

Application14/622,101Continuation

US 2013/0162244 A1Published application

US 9,182,455 B2Related patent

US 9,348,002 B2Related patent

US 2015/0177338 A1This patent

From the US filing history. Foreign family members aren’t listed.

Dla rotor flux density scan method and tool

Life of this patent

Dla rotor flux density scan method and tool

Life of this patent

Abstract

Claims17