US3750010A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vibration analyzer probe with reduced temperature sensitivity
Assignee: Reliance Electric Co
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Filing: 1970-03-25
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Granted: 1973-07-31
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Expires: 1990-03-25
Abstract
Abstract Disclosed is a simplified and inexpensive probe for noncontacting vibration analyzers, and an analyzer employing the probe, which probe is substantially insensitive to temperature variations. The probe comprises a bridge including sensor and reference coils in two bridge legs forming the primaries of two transformers. A pair of resistors form the other bridge legs. The bridge is excited from an AC source and the transformer secondaries are coupled through a pair of large resistors to the remainder of the vibration analyzer.
Inventors
- 👤 A Abnett
- 👤 R Boley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:52
CPC Classifications
G; G01; G01M; G01M7/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
182 words
A substantially temperature insensitive probe for a noncontact vibration analyzer comprising: a bridge having a first resistor in a first arm of said bridge, a second resistor in a second arm of said bridge, a reference coil in a third arm of said bridge, and a sensor coil in a fourth arm of said bridge; first means for coupling an oscillator to a point on said bridge intermediate said first and second resistors and second means for coupling said oscillator to a point intermediate said reference and sensor coils; a third coil inductively coupled to said reference coil; a fourth coil inductively coupled to said sensor coil; a third resistor in series with said third coil; a fourth resistor in series with said fourth coil, said first and second resistors being of high resistance relative to the resistances of said reference and sensor coils, and said third and fourth resistors being of high resistance relative to the resistances of said third and fourth coils, and means for coupling said third and fourth coils and resistors to the input of a vibration analyzer.
Claim 2
Dependent Claim
182 words
A substantially temperature insensitive probe for a noncontact vibration analyzer comprising: a bridge having a first resistor in a first arm of said bridge, a second resistor in a second arm of said bridge, a reference coil in a third arm of said bridge, and a sensor coil in a fourth arm of said bridge; first means for coupling an oscillator to a point on said bridge intermediate said first and second resistors and second means for coupling said oscillator to a point intermediate said reference and sensor coils; a third coil inductively coupled to said reference coil; a fourth coil inductively coupled to said sensor coil; a third resistor in series with said third coil; a fourth resistor in series with said fourth coil, said first and second resistors being of high resistance relative to the resistances of said reference and sensor coils, and said third and fourth resistors being of high resistance relative to the resistances of said third and fourth coils, and means for coupling said third and fourth coils and resistors to the input of a vibration analyzer.
Claim 3
Dependent Claim
37 words
A probe according to claim 1 wherein said reference and sensor coils comprise the primaries of first and second transformers, and wherein said third and fourth coils comprise the secondaries of said first and second transformers, respectively.
Claim 4
Dependent Claim
22 words
A probe according to claim 1 wherein said oscillator operates at a frequency of from about 100 KHz to about 1 MHz.
Claim 5
Dependent Claim
67 words
A probe according to claim 1 wherein said first resistor and said reference coil are connected in series between said first oscillator coupling means and a ground terminal, said second resistor and sensor coil are connected in series between said first oscillator coupling means and said ground terminal, and said third and fourth coils are connected in series, with a junction therebetween connected to said ground terminal.
Claim 6
Dependent Claim
35 words
A probe according to claim 4 wherein said first coupling means cOmprises a balancing potentiometer having its ends connected between said first and second resistors, and its arm adapted to be connected to said oscillator.
Claim 7
Dependent Claim
16 words
A probe according to claim 5 wherein all said coils are wound on a common core.
Claim 8
Dependent Claim
46 words
A probe according to claim 1 including a core having a pair of spaced annular slots, said third coil being wound over said reference coil in one of said slots, and said fourth coil being wound over said sensor coil in the other of said slots.
Claim 9
Dependent Claim
30 words
A probe according to claim 7 wherein said core has an end with a flat face, said sensor coil and said fourth coil being in the slot nearest said face.
Claim 10
Dependent Claim
21 words
A probe according to claim 8 wherein said slots are spaced apart about one-half inch along the length of said core.
Claim 11
Dependent Claim
86 words
A noncontact vibration analyzer comprising a probe as defined in claim 1; an oscillator connected to said first and second coupling means; and measuring means connected to said third and fourth resistors, said measuring means being operative to produce a signal having AC and DC components which vary similarly with a standoff distance of said probe from a metal surface, and including an automatic gain control circuit responsive to said DC component for maintaining the same constant, whereby said AC component is substantially independent of standoff.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |