US3899663A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measuring dimensions of sections
Assignee: Centre de Recherches Metallurgiques CRM ASBL
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Filing: 1973-06-18
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Granted: 1975-08-12
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Expires: 1993-06-18
Abstract
Abstract To measure the dimensions of an elongate section such as a rolled or extruded section, two fixed observation points are chosen so that the elongate section lies between them. Two directional telemeters are arranged to measure the distance from the respective observation points to the section along a directional axis which is pivotable about a pivot axis passing through the corresponding observation point and extending along the elongate section; the observation points and directional axes lie in a single plane transverse to the elongate section, and the intersection of this plane with the elongate section has a periphery which is the sectional contour of the elongate section. The sectional contour is scanned by means of the telemeters by pivoting the directional axes about the pivot axes. The distance and direction of a plurality of points on the sectional contour with respect to the corresponding observation point are recorded. The dimensions of the elongate section are computed from the said distances and directions.
Inventors
- 👤 Robert Alfred Pirlet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:08
CPC Classifications
G; G01; G01B; G01B7/00; G01B7/28; B; B21; B21B; B21B38/00; B21B38/04; G01B11/00; G01B11/24; G01B15/00; G01B15/04
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
153 words
A method of measuring the dimensions of an elongate section, comprising: selecting two fixed observation points so that the elongate section lies between them; arranging two directional telemeters to measure the distance from the respective observation points to the section along a directional axis which is pivotable about a pivot axis passing through the corresponding observation point and extending along the elongate section, the observation points and directional axes lying in a single plane transverse to the elongate section the intersection of this plane with the elongate section having a periphery which is the sectional contour of the elongate section; scanning the sectional contour by means of the telemeters by pivoting the directional axes about the pivot axes; recording the distance and direction of a plurality of points on the sectional contour with respect to the corresponding observation point; and calculating the dimensions of the elongate section from the said distances and directions.
Claim 2
Independent Claim
153 words
A method of measuring the dimensions of an elongate section, comprising: selecting two fixed observation points so that the elongate section lies between them; arranging two directional telemeters to measure the distance from the respective observation points to the section along a directional axis which is pivotable about a pivot axis passing through the corresponding observation point and extending along the elongate section, the observation points and directional axes lying in a single plane transverse to the elongate section the intersection of this plane with the elongate section having a periphery which is the sectional contour of the elongate section; scanning the sectional contour by means of the telemeters by pivoting the directional axes about the pivot axes; recording the distance and direction of a plurality of points on the sectional contour with respect to the corresponding observation point; and calculating the dimensions of the elongate section from the said distances and directions.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1, wherein the number of points whose distance and direction are recorded is the number necessary and sufficient to characterise all the dimensions of the sectional contour.
Claim 4
Dependent Claim
105 words
A method as claimed in claim 1, wherein the elongate section has two lateral flanges connected by a web, and wherein the points on one side of the sectional contour whose distance and direction with respect to the corresponding observation point are recorded are at least four in number, these being the two ends of this side of contour; the point at which the straight line connecting the two observation points intersects this side of the contour; this point lying on the web, the web being transverse to the said straight line; two points each being situated on the inner face of each said flange.
Claim 5
Dependent Claim
31 words
A method as claimed in claim 3 wherein the direction of each point is determined with respect to a reference direction perpendicular to the straight line connecting the two observation points.
Claim 6
Dependent Claim
75 words
A method as claimed in claim 3, wherein the two ends of the contour are detected by systematically scanning the contour between two directions at which the distance measured by the telemeter is infinite, one end of the contour being detected when the value of the distance measured passes from an infinite value to a finite value, the other when the value of the distance measured passes from a finite value to an infinite value.
Claim 7
Dependent Claim
43 words
A method as claimed in claim 4, wherein the point at which the straight line connecting the two observation points intersects the contour is taken to be the point at which the angle between the directional axis and the reference direction is 90*.
Claim 8
Dependent Claim
69 words
A method as claimed in claim 4, wherein the point situated on the said face of one said flange is detected by scanning at a constant angular velocity and automatically calculating the first derivative with respect to time of the product of the measured distance times the cosine of the angle between the directional axis and the reference direction, the point being detected when the said derivative is zero.
Claim 9
Dependent Claim
60 words
A method as claimed in claim 1, wherein the said distances and directions are recorded in a memory store, and the calculation of the dimensions is carried out by a computer while the scanning operation is completed, the memorised data then being automatically erased so that a new series of measurements may be recorded when a fresh scanning operation starts.
Claim 10
Dependent Claim
58 words
A method aS claimed in claim 1, wherein the distance between one of the said points and the observation point is measured by means of the telemeter by directing electromagnetic radiation towards that point, receiving the radiation reflected by the said point, and measuring the time taken by the radiation in travelling to and from the said point.
Claim 11
Dependent Claim
13 words
A method as claimed in claim 9, wherein the radiation is laser radiation.
Claim 12
Dependent Claim
15 words
A method as claimed in claim 9, wherein the radiation is millimetric or sub-millimetric wavelength.
Claim 13
Dependent Claim
29 words
A method as claimed in claim 1, including automatically synchronising the pivotal motion of the two directional axes so that their orientations are equal at all times during scanning.
Claim 14
Dependent Claim
66 words
A method as claimed in claim 1, wherein the distances separating the observation points from each of the faces of the elongate section intersected perpendicularly by the straight line connecting the two observation points are equal when the distance between these two faces is equal to half the sum of the upper and lower values of this distance tolerated in the manufacture of the elongate section.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |