US5014547A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for determining the surface roughness of a material
Assignee: Rolls Royce DSV Ltd
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Filing: 1989-10-06
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Granted: 1991-05-14
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Expires: 2009-10-06
Abstract
Abstract An apparatus for determining the surface roughness of a material comprised of an acoustic element which is pivotally mounted to a support structure containing a polished end which is maneuvered into contact with the surface of a material to be tested by a spring element. The material is caused to move relative to the acoustic element by a driven roller. A transducer is acoustically coupled to the acoustic element and detects stress waves propagating in the acoustic element as a result of frictional and impact force generated by the rubbing of the acoustic element with the material. The relative stress wave activity is dependent upon the surface roughness of the material. A processor analyzes an electrical signal produced by the transducer to determine the surface roughness of the material which may analyze the electrical signal produced by the transducer to determine the presence of impurities on the surface of the material.
Inventors
- 👤 Trevor J. Holroyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:36
CPC Classifications
G; G01; G01B; G01B17/00; G01B17/08; G01B7/00; G01B7/34; G01N; G01N29/00; G01N29/14; G01N2291/00; G01N2291/02; G01N2291/023; G01N2291/0237; G01N2291/26; G01N2291/263; G01N2291/2632
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
173 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said acoustic element being shaped and configured such that the stress waves propagating in the acoustic element have a relatively low decay rate at the frequency or frequencies being detected in order to create a diffuse stress wave field.
Claim 2
Independent Claim
173 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said acoustic element being shaped and configured such that the stress waves propagating in the acoustic element have a relatively low decay rate at the frequency or frequencies being detected in order to create a diffuse stress wave field.
Claim 3
Dependent Claim
25 words
An apparatus as claimed in claim 1 in which the at least one acoustic element is biassed into contact with the surface of the material.
Claim 4
Dependent Claim
47 words
An apparatus as claimed in claim 1 in which a plurality of acoustic elements are arranged in contact with the surface of the material, the acoustic elements being spaced transversely of the material with respect to the direction of relative movement of the material and acoustic elements.
Claim 5
Dependent Claim
14 words
An apparatus as claimed in claim 3 in which the acoustic elements are equi-spaced.
Claim 6
Dependent Claim
44 words
An apparatus as claimed in claim 1 in which the acoustic element extends transversely of the material with respect to the direction of relative movement of the material and acoustic element, the acoustic element making contact with substantially the full width of the material.
Claim 7
Dependent Claim
18 words
An apparatus as claimed in claim 5 in which the acoustic element is rotated about an axis thereof.
Claim 8
Dependent Claim
19 words
An apparatus as claimed in claim 1 in which a single transducer is acoustically coupled to each acoustic element.
Claim 9
Dependent Claim
15 words
An apparatus as claimed in claim 1 in which the material is a thin sheet.
Claim 10
Dependent Claim
18 words
An apparatus as claimed in claim 1 in which the material is moved relative to the acoustic element.
Claim 11
Dependent Claim
19 words
An apparatus as claimed in claim 9 in which the acoustic element is pivotally mounted to a support structure.
Claim 12
Dependent Claim
35 words
An apparatus as claimed in claim 1 in which the means to determine the surface roughness of the material produces an output signal which operates an alarm when the surface roughness reaches a predetermined value.
Claim 13
Dependent Claim
45 words
An apparatus as claimed in claim 1 in which the means to determine the surface roughness of the material produces an output signal which operates a marker device when the surface roughness reaches a predetermined value, the marker device applies a mark onto the material.
Claim 14
Dependent Claim
33 words
An apparatus as claimed in claim 1 in which the means to determine the surface roughness of the material is arranged to determine the presence of impurities at the surface of the material.
Claim 15
Independent Claim
178 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said means to determine the surface roughness of the material producing an output signal which controls the means to cause relative movement between the acoustic element and the material to at least reduce the relative movement when the surface roughness reaches a pre-determined value.
Claim 16
Independent Claim
178 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said means to determine the surface roughness of the material producing an output signal which controls the means to cause relative movement between the acoustic element and the material to at least reduce the relative movement when the surface roughness reaches a pre-determined value.
Claim 17
Independent Claim
174 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said means to determine the surface roughness of the material being arranged to determine the presence of impurities at the surface of the material, and which operates a device to remove impurities when the surface roughness reaches a predetermined value.
Claim 18
Independent Claim
174 words
An apparatus for determining the surface roughness of a material comprising at least one acoustic element arranged in contact with a surface of the material, means to cause relative movement between the at least one acoustic element and the material such that frictional contact between the at least one acoustic element and the material generates stress waves which propagate within the at least one acoustic element, the stress wave activity within the acoustic element being dependent upon the surface roughness of the material, acoustic emission transducer means acoustically coupled to the at least one acoustic element arranged to detect stress waves propagating in the at least one acoustic element and to produce at least one electrical signal, and means to determine from the at least one electrical signal the surface roughness of the material, said means to determine the surface roughness of the material being arranged to determine the presence of impurities at the surface of the material, and which operates a device to remove impurities when the surface roughness reaches a predetermined value.
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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) | 1994-05-13 | 1994-11-12 | 1995-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-13 | 1998-11-12 | 1999-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-13 | 2002-11-12 | 2003-05-14 | $7700.00 | Window Closed / Lapsed |