US3885318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface profile testing instrument
Assignee: Rank Organization Ltd
•
Filing: 1973-07-12
•
Granted: 1975-05-27
•
Expires: 1993-07-12
Abstract
Abstract An instrument for testing the profile of a surface of an object having a non-circular, e.g. trochoidal, nominal shape, in which relative rotation is effected betweeen the object under test and the transducer, this relative rotation being compounded of two independent simultaneous rotations about parallel spaced apart axes so arranged that the transducer feeler traces a path which conforms to the nominal shape so that the transducer detects departures from the nominal shape. Automatic correction may be made for changes in the angle of the transducer feeler relative to the surface as the surface is scanned by the feeler.
Inventors
- 👤 David John Whitehouse
- 👤 Melton Mowbray
- 👤 Robert Claude Spragg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:05
CPC Classifications
G; G01; G01B; G01B5/00; G01B5/20
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
160 words
An instrument for testing the profile of a surface of an object having a nominal shape which is non-circular, said instrument comprising: a surface transducer having a feeler adapted to engage the surface of the object; mounting means for the object under test, rotatable about a first axis; support means carrying said mounting means, said support means being rotatable about a second axis spaced from and parallel to the first axis; means supporting the transducer at a fixed position relative to said second axis, and drive means for effecting rotation of the mounting means about the first axis and rotation of the support means about the second axis to cause the feeler to move over the surface of the object, wherein the resultant path traced by the feeler relative to said surface of the object under the action of said drive means conforms to said nominal shape, the transducer being responsive to departures of said surface from said nominal shape.
Claim 2
Dependent Claim
160 words
An instrument for testing the profile of a surface of an object having a nominal shape which is non-circular, said instrument comprising: a surface transducer having a feeler adapted to engage the surface of the object; mounting means for the object under test, rotatable about a first axis; support means carrying said mounting means, said support means being rotatable about a second axis spaced from and parallel to the first axis; means supporting the transducer at a fixed position relative to said second axis, and drive means for effecting rotation of the mounting means about the first axis and rotation of the support means about the second axis to cause the feeler to move over the surface of the object, wherein the resultant path traced by the feeler relative to said surface of the object under the action of said drive means conforms to said nominal shape, the transducer being responsive to departures of said surface from said nominal shape.
Claim 3
Dependent Claim
83 words
The instrument defined in claim 1, wherein the transducer feeler has a direction of maximum sensitivity in respect of the detection of surface variations by the transducer, and including compensating means connected to the transducer and effective to modify the output of the transducer to compensate for changes in said output due to changes in the angle between said direction of maximum sensitivity of the transducer feeler and the surface of the object under test at its point of contact with the feeler.
Claim 4
Dependent Claim
80 words
The instrument defined in claim 1, including swivel mounting means for the transducer feeler, permitting rocking movement of the feeler about an axis parallel to said first axis, said mounting means including surface contact elements which engage the surface of the object under test on each side of the transducer feeler to maintain the feeler with its direction of maximum sensitivy generally perpendicular to the surface of the object at the point of contact of the feeler with said surface.
Claim 5
Dependent Claim
93 words
The instrument defined in claim 1, wherein the nominal shape is trochoidal and further including polar recording means for recording the surface profile of the object in polar coordinates the polar angle of which at any given instant corresponds to the instantaneous polar angle theta of the rotation about one of the two axes of rotation, and means modifying said polar angle by a correction for the angular displacement between the surface feeler and the line joining the two axes of rotation, said angular correction being a function of the angle theta .
Claim 6
Dependent Claim
29 words
The instrument defined in claim 4, whErein the angular correction is proportional to sin n theta , where n is the number of lobes of the trochoidal nominal shape.
Claim 7
Dependent Claim
23 words
The instrument defined in claim 5, wherein the trochoidal nominal shape has two lobes (n 2) and the angular correction is given by:
Claim 8
Dependent Claim
29 words
The instrument defined in claim 4, wherein the means modifying the polar angle are effective to modulate the polar angle display of the recording means with said angular correction.
Claim 9
Dependent Claim
37 words
The instrument defined in claim 7, wherein the polar recording means has a chart and means rotating said chart at a rotational speed having a constant component and a sinusoidal modulation component proportional to the angular correction.
Claim 10
Dependent Claim
28 words
The instrument defined in claim 7, wherein the modulating means for the polar angle display comprise synchronous detector means responsive to the rotation about one of said axes.
References Cited (Backward Citations)
US2422034A
Cited
US3808944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-26 | 1978-11-25 | 1979-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-26 | 1982-11-25 | 1983-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-26 | 1986-11-25 | 1987-05-27 | $7700.00 | Window Closed / Lapsed |