US3921065A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic sensor for detecting flaws on one surface of roller bearing
Assignee: Individual
•
Filing: 1974-02-15
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Granted: 1975-11-18
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Expires: 1994-02-15
Abstract
Abstract A bearing tester for electromagnetically detecting flaws in a surface of a bearing. The tester includes a probe having a sensor that moves between the cage and inner race of the bearing. The sensor is automatically vertically moved across the surface of the inner race to detect flaws and is positioned laterally with an adjustment mechanism to fit between the cage and inner race. Vertical movement of the sensor is automatically accomplished through the use of circuitry that generates a signal corresponding to the vertical displacement of the probe and compares the signal to two predetermined thresholds representing, respectively, first and second vertical positions corresponding to the upper and lower parts of the inner race. Movement of the probe to the first and second vertical positions automatically energizes and deenergizes, respectively, a motor which drives the probe and rotates the inner race. The sensor includes a barrel and centerpiece made of relay core material, together with a coil wound about the centerpiece. The inductance of the coil is proportional to the strength of the magnetic loop formed by the barrel, centerpiece and inner race. A change in inductance resulting from a flaw in the surface of the inner race is detected and a signal is generated proportional to such change to provide visual information of the flaw.
Inventors
- 👤 Wendell G Rawlins
- 👤 Gary M Hoffsommer
- 👤 Charles W Artzer
- 👤 Cecil H Parrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:28
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/145; F; F16; F16C; F16C33/00; F16C33/30; F16C33/58; F16C33/64; G01N; G01N27/00; G01N27/72; G01N27/82; G01N27/90; G01N27/9093
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
305 words
Apparatus for detecting flaws in a surface of a large roller bearing having an inner race, a cage spaced apart form and concentric about the inner race, and a plurality of rollers connected to the cage and abutting the outer surface of the inner race, comprising: a. a probe including a sensor facing towards and in contact with the outer surface of the inner race, said sensor including means for providing a magnetic field having magnetic lines of force in a loop about said sensor and the inner race, said sensor having an inductive reactance which is proportional to the number of magnetic lines of force in the loop; b. first means for moving said probe with respect to the roller bearing to enable said sensor to be positioned between the outer surface of the inner race and the cage; c. second means for automatically moving said sensor vertically across the outer surface of the inner race including a motor connected to said probe, means for providing a signal corresponding to the vertical position of said probe, means connected to said providing means for energizing said motor when said probe is at a first vertical position with respect to the roller bearing, and means connected to said providing means for deenergizing said motor when said probe is at a second vertical position with respect to the roller bearing lower than the first vertical position; d. means for rotating the roller bearing about a vertical axis, including said motor; e. means for determining a change in inductive reactance of said sensor when said sensor moves across a flaw in the outer surface of the inner race providing an air gap between said sensor and the outer surface; and f. means connected to said determining means, for displaying information corresponding to the condition of the outer surface.
Claim 2
Dependent Claim
305 words
Apparatus for detecting flaws in a surface of a large roller bearing having an inner race, a cage spaced apart form and concentric about the inner race, and a plurality of rollers connected to the cage and abutting the outer surface of the inner race, comprising: a. a probe including a sensor facing towards and in contact with the outer surface of the inner race, said sensor including means for providing a magnetic field having magnetic lines of force in a loop about said sensor and the inner race, said sensor having an inductive reactance which is proportional to the number of magnetic lines of force in the loop; b. first means for moving said probe with respect to the roller bearing to enable said sensor to be positioned between the outer surface of the inner race and the cage; c. second means for automatically moving said sensor vertically across the outer surface of the inner race including a motor connected to said probe, means for providing a signal corresponding to the vertical position of said probe, means connected to said providing means for energizing said motor when said probe is at a first vertical position with respect to the roller bearing, and means connected to said providing means for deenergizing said motor when said probe is at a second vertical position with respect to the roller bearing lower than the first vertical position; d. means for rotating the roller bearing about a vertical axis, including said motor; e. means for determining a change in inductive reactance of said sensor when said sensor moves across a flaw in the outer surface of the inner race providing an air gap between said sensor and the outer surface; and f. means connected to said determining means, for displaying information corresponding to the condition of the outer surface.
Claim 3
Dependent Claim
41 words
Apparatus according to claim 1 wherein said means for energizing and said means for deenergizing comprise signal level comparators having respective preset thresholds representing the first and second positions, respectively, said signal from said providing means being compared to said thresholds.
Claim 4
Dependent Claim
30 words
Apparatus according to claim 2 wherein said comparators include means for changing said thresholds to vary the vertical positions of said probe at which said motor is energized and deenergized.
Claim 5
Dependent Claim
101 words
Apparatus according to claim 3 wherein said second means for automatically moving comprises a rotatable drive rod driven by said motor, means rotatably mounting said drive rod to said motor, a support plate having an aperture through which said drive rod extends and for moving vertically along said rod, said first means for moving connecting said probe to said supporting plate, a solenoid energized by said motor energizing means and connected to said plate, and means, connected to said solenoid and operated by said solenoid when said solenoid is energized, for engaging said drive rod and vertically moving said support plate.
Claim 6
Dependent Claim
33 words
Apparatus according to claim 4 wherein said first means for moving comprises means pivotally mounting said probe about a horizontal axis, and third means for moving said mounting means about the horizontal axis.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |