US5619587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for contactlessly gauging the thickness of a contoured object, such as a vehicle wheel
Assignee: Alcoa Corp
•
Filing: 1993-12-15
•
Granted: 1997-04-08
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Expires: 2013-12-15
Abstract
Abstract There is disclosed a system for visually measuring the cross-sectional thickness of a light-reflective object, such as a vehicle wheel, said object having a plurality of curved surfaces. The system includes: means for transmitting a line of light onto each curved surface of the object at substantially the same cross-sectional area through the object; means for sensing the lines of light reflected from each curved surface and producing a plurality of signals thereby, said signals representing a linear profile of each curved surface at the same cross-sectional area; and means for comparing the profile signals from each curved surface for calculating a cross-sectional thickness of the object at one or more points along the same cross-sectional area. On a more preferred basis, this system further includes means for supporting the object, and means for rotating the object about at least one axis of support to measure a plurality of cross-sectional thicknesses thereof. Most preferably, the light transmittal means of this system include a plurality of light sources for transmitting collimated laser lines across the object's inner curved surfaces from opposite sides of the object substantially simultaneously. A method for inspecting a vehicle wheel to determine whether it is within dimensional specification is also disclosed. This method employs a system substantially as set forth above.
Inventors
- 👤 Louis G. Willoughby, Jr.
- 👤 Donald G. Jordan
- 👤 Paul R. Adomaitis
- 👤 Avraham C. Goldman
- 👤 Anthony J. Tomasello
- 👤 Steve Montellese
- 👤 Edward W. Weed
- 👤 Abraham Shtrahman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:56
CPC Classifications
B; B21; B21C; B21C51/00; G; G01; G01B; G01B11/00; G01B11/24; G01B11/245
Claims Analysis
Total Claims: 58
Claim 1
Independent Claim
299 words
Method for contactlessly measuring the shape and cross sectional dimensions of a substantially hollow cylindrical object having at least one open end, an inner surface and an outer surface, and having an object longitudinal axis extending therethrough, said method comprising the steps of: a) positioning said object on a support which defines a support longitudinal axis extending parallel to said object longitudinal axis, said support also defining a reference plane at a known location and extending perpendicular to said support longitudinal axis; b) illuminating at least a portion of the outer surface of said object along an outer line in a first inspection plane extending perpendicular to said reference plane and through said support longitudinal axis at a first inspection position on said object; c) detecting the illumination on said object along said outer line and, in response thereto, generating a first location signal representing the locations of said portion of the outer surface of said object along said outer line with respect to said support longitudinal axis and said reference plane; d) illuminating at least a portion of the inner surface of said object through said open end along an inner line in said first inspection plane; e) detecting the illumination on said object along said inner line and, in response thereto, generating a second location signal representing the locations of said portion of the inner surface of said object along said inner line with respect to said support longitudinal axis and said reference plane; and f) combining said first location signal and said second location signal with respect to said support longitudinal axis and said reference plane and generating a cross section signal representing the dimensions of at least a portion of said object between said outer surface and said inner surface at said first inspection position.
Claim 2
Dependent Claim
299 words
Method for contactlessly measuring the shape and cross sectional dimensions of a substantially hollow cylindrical object having at least one open end, an inner surface and an outer surface, and having an object longitudinal axis extending therethrough, said method comprising the steps of: a) positioning said object on a support which defines a support longitudinal axis extending parallel to said object longitudinal axis, said support also defining a reference plane at a known location and extending perpendicular to said support longitudinal axis; b) illuminating at least a portion of the outer surface of said object along an outer line in a first inspection plane extending perpendicular to said reference plane and through said support longitudinal axis at a first inspection position on said object; c) detecting the illumination on said object along said outer line and, in response thereto, generating a first location signal representing the locations of said portion of the outer surface of said object along said outer line with respect to said support longitudinal axis and said reference plane; d) illuminating at least a portion of the inner surface of said object through said open end along an inner line in said first inspection plane; e) detecting the illumination on said object along said inner line and, in response thereto, generating a second location signal representing the locations of said portion of the inner surface of said object along said inner line with respect to said support longitudinal axis and said reference plane; and f) combining said first location signal and said second location signal with respect to said support longitudinal axis and said reference plane and generating a cross section signal representing the dimensions of at least a portion of said object between said outer surface and said inner surface at said first inspection position.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein steps b-f are repeated at a plurality of inspection positions spaced about said object.
Claim 4
Dependent Claim
17 words
The method of claim 2 wherein said inspection positions are spaced at regular intervals about said object.
Claim 5
Dependent Claim
23 words
The method of claim 2 further including the step of sequentially rotating said support about said support longitudinal axis to each inspection position.
Claim 6
Dependent Claim
121 words
The method of claim 1 wherein said object includes an end surface and said method further includes the steps of: g) illuminating at least a portion of the end surface of said object along an end line in said first inspection plane; h) detecting the illumination on said object along said end line and, in response thereto, generating a third location signal representing the locations of said portion of the end surface of said object along said end line with respect to said support longitudinal axis and said reference plane; and i) combining said third location signal with said first and second location signals with respect to said support longitudinal axis and said reference plane for generating said cross section signal.
Claim 7
Dependent Claim
20 words
The method of claim 5 wherein steps b-i are repeated at a plurality of inspection positions spaced about said object.
Claim 8
Dependent Claim
17 words
The method of claim 6 wherein said inspection positions are spaced at regular intervals about said object.
Claim 9
Dependent Claim
23 words
The method of claim 6 further including the step of sequentially rotating said support about said support longitudinal axis to each inspection position.
Claim 10
Dependent Claim
36 words
The method of claim 2 further including the step of generating, at each inspection position, a radial signal representing radial dimensions of at least a portion of said object with respect to said support longitudinal axis.
Claim 11
Dependent Claim
86 words
The method of claim 9 further including the steps of selecting a radial dimension of said object at the same object location in at least three of said inspection positions, determining the radial center of an imaginary circle passing through said selected radial dimensions, determining a radial difference between the support longitudinal axis and said radial center, and adjusting the location signals, cross section signals and radial signals in a vector operation which considers the magnitude and direction of said radial difference in each inspection plane.
Claim 12
Dependent Claim
22 words
The method of claim 1 wherein the outer surface of said object is illuminated by a backlight spaced from said inspection plane.
Claim 13
Dependent Claim
18 words
The method of claim 1 wherein the outer surface of said object is illuminated by a collimated laser.
Claim 14
Dependent Claim
28 words
The method of claim 1 wherein the inner surface of said object is illuminated by a first laser projecting a line of laser light along said inner line.
Claim 15
Dependent Claim
52 words
The method of claim 5 wherein the inner surface of said object is illuminated by a first laser projecting a line of laser light along said inner line and wherein the end surface of said object is illuminated by a second laser projecting a line of laser light along said end line.
Claim 16
Dependent Claim
22 words
The method of claim 14 wherein said lasers are each Helium Neon lasers having a line generator on the output laser beams.
Claim 17
Dependent Claim
60 words
The method of claim 5 wherein the illumination on said object along said outer line, inner line and end line is detected by a first video camera, a second video camera, and a third video camera, respectively, and wherein said location signals are generated by an electronic video image processor receiving an output signal from each of said video cameras.
Claim 18
Dependent Claim
14 words
The method of claim 16 wherein said video cameras are charge coupled device cameras.
Claim 19
Dependent Claim
84 words
The method of claim 16 wherein each video camera generates a two dimensional pixel array representing the light intensity of the object detected by the camera, wherein the video image processor conducts a row-by-row evaluation of each pixel array and determines which pixels, if any, in each row represent illumination detected on said object, and wherein the video image processor assigns to each of said pixels representing said detected illumination a precise location with respect to said support longitudinal axis and said reference plane.
Claim 20
Dependent Claim
18 words
The method of claim 18 wherein the video processor evaluates each pixel array by an edge detection technique.
Claim 21
Dependent Claim
26 words
The method of claim 18 wherein a plurality of pixel arrays are averaged together for each video camera prior to evaluation by the video image processor.
Claim 22
Dependent Claim
48 words
The method of claim 18 wherein the video image processor, after it has determined which pixels in each row represent said detected illumination, uses polynomial mathematical techniques to generate a precise curve through the pixels representing the detected illumination and corresponding to the associated surfaces of said object.
Claim 23
Dependent Claim
12 words
The method of claim 1 wherein said object is a vehicle wheel.
Claim 24
Dependent Claim
13 words
The method of claim 1 wherein said object is a forged aluminum wheel.
Claim 25
Dependent Claim
43 words
The method of claim 2 further including the steps of comparing said location signals and cross section signals actually generated from said object with predetermined standards for said object, and then determining whether said object is within acceptable tolerances for said predetermined standards.
Claim 26
Dependent Claim
84 words
The method of claim 16 wherein each video camera generates a two dimensional pixel array representing the light intensity of the object detected by the camera, wherein the video image processor conducts a column-by-column evaluation of each pixel array and determines which pixels, if any, in each column represent illumination detected on said object, and wherein the video image processor assigns to each of said pixels representing said detected illumination a precise location with respect to said support longitudinal axis and said reference plane.
Claim 27
Dependent Claim
18 words
The method of claim 25 wherein the video processor evaluates each pixel array by an edge detection technique.
Claim 28
Dependent Claim
26 words
The method of claim 25 wherein a plurality of pixel arrays are averaged together for each video camera prior to evaluation by the video image processor.
Claim 29
Dependent Claim
48 words
The method of claim 25 wherein the video image processor, after it has determined which pixels in each column represent said detected illumination, uses polynomial mathematical techniques to generate a precise curve through the pixels representing the detected illumination and corresponding to the associated surfaces of said object.
Claim 30
Dependent Claim
333 words
Apparatus for contactlessly measuring the shape and cross sectional dimensions of a substantially hollow cylindrical object having at least one open end, an inner surface and an outer surface, and having an object longitudinal axis extending therethrough, said apparatus comprising: a) means for positioning said object on a support defining a support longitudinal axis extending parallel to said object longitudinal axis, said support also defining a reference plane at a known location and extending perpendicular to said support longitudinal axis; b) first illumination means for illuminating at least a portion of the outer surface of said object along an outer line in a first inspection plane extending perpendicular to said reference plane and through said support longitudinal axis at a first inspection position on said object; c) first detection means for detecting the illumination on said object along said outer line and first generation means for generating, in response to said first detection means, a first location signal representing the locations of said portion of the outer surface of said object along said outer line with respect to said support longitudinal axis and said reference plane; d) second illumination means for illuminating at least a portion of the inner surface of said object through said open end along an inner line in said first inspection plane; e) second detection means for detecting the illumination on said object along said inner line and second generation means for generating, in response to said second detection means, a second location signal representing the locations of said portion of the inner surface of said object along said inner line with respect to said support longitudinal axis and said reference plane; and f) first processor means for combining said first location signal and said second location signal with respect to said support longitudinal axis and said reference plane and generating a cross section signal representing the dimensions of at least a portion of said object between said outer surface and said inner surface at said first inspection position.
Claim 31
Dependent Claim
333 words
Apparatus for contactlessly measuring the shape and cross sectional dimensions of a substantially hollow cylindrical object having at least one open end, an inner surface and an outer surface, and having an object longitudinal axis extending therethrough, said apparatus comprising: a) means for positioning said object on a support defining a support longitudinal axis extending parallel to said object longitudinal axis, said support also defining a reference plane at a known location and extending perpendicular to said support longitudinal axis; b) first illumination means for illuminating at least a portion of the outer surface of said object along an outer line in a first inspection plane extending perpendicular to said reference plane and through said support longitudinal axis at a first inspection position on said object; c) first detection means for detecting the illumination on said object along said outer line and first generation means for generating, in response to said first detection means, a first location signal representing the locations of said portion of the outer surface of said object along said outer line with respect to said support longitudinal axis and said reference plane; d) second illumination means for illuminating at least a portion of the inner surface of said object through said open end along an inner line in said first inspection plane; e) second detection means for detecting the illumination on said object along said inner line and second generation means for generating, in response to said second detection means, a second location signal representing the locations of said portion of the inner surface of said object along said inner line with respect to said support longitudinal axis and said reference plane; and f) first processor means for combining said first location signal and said second location signal with respect to said support longitudinal axis and said reference plane and generating a cross section signal representing the dimensions of at least a portion of said object between said outer surface and said inner surface at said first inspection position.
Claim 32
Dependent Claim
22 words
The apparatus of claim 29 further including means for measuring said object at a plurality of inspection positions spaced about said object.
Claim 33
Dependent Claim
17 words
The apparatus of claim 30 wherein said inspection positions are spaced at regular intervals about said object.
Claim 34
Dependent Claim
28 words
The apparatus of claim 30 further including means for sequentially rotating said support about said support longitudinal axis to measure said object at each of said inspection positions.
Claim 35
Dependent Claim
138 words
The apparatus of claim 29 wherein said object includes an end surface and said apparatus further includes: g) third illumination means for illuminating at least a portion of the end surface of said object along an end line in said first inspection plane; h) third detection means for detecting the illumination on said object along said end line and third generation means for generating, in response to said third generation means, a third location signal representing the locations of said portion of the end surface of said object along said end line with respect to said support longitudinal axis and said reference plane; and i) second processor means for combining said third location signal with said first and second location signals with respect to said support longitudinal axis and said reference plane for generating said cross section signal.
Claim 36
Dependent Claim
22 words
The apparatus of claim 33 further including means for measuring said object at a plurality of inspection positions spaced about said object.
Claim 37
Dependent Claim
17 words
The apparatus of claim 34 wherein said inspection positions are spaced at regular intervals about said object.
Claim 38
Dependent Claim
22 words
The apparatus of claim 34 further including means for sequentially rotating said support about said support longitudinal axis to each inspection position.
Claim 39
Dependent Claim
35 words
The apparatus of claim 30 further including means for generating, at each inspection position, a radial signal representing radial dimensions of at least a portion of said object with respect to said support longitudinal axis.
Claim 40
Dependent Claim
92 words
The apparatus of claim 37 further includes means for selecting a radial dimension of said object at the same object location in at least three of said inspection positions, means for determining the radial center of an imaginary circle passing through said selected radial dimensions, means for determining a radial difference between the support longitudinal axis and said calculated radial center, and means for adjusting the location signals, cross section signals and radial signals in a vector operation which considers the magnitude and direction of said radial difference in each inspection plane.
Claim 41
Dependent Claim
18 words
The apparatus of claim 29 wherein said first illumination means is a backlight spaced from said inspection plane.
Claim 42
Dependent Claim
14 words
The apparatus of claim 29 wherein said first illumination means is a collimated laser.
Claim 43
Dependent Claim
24 words
The apparatus of claim 29 wherein said second illumination means is a first laser projecting a line of laser light along said inner line.
Claim 44
Dependent Claim
44 words
The apparatus of claim 33 wherein said second illumination means is a first laser projecting a line of laser light along said inner line and wherein said third illumination means is a second laser projecting a line of laser light along said end line.
Claim 45
Dependent Claim
21 words
The apparatus of claim 42 wherein said lasers are each Helium-Neon lasers having a line generator on the output laser beams.
Claim 46
Dependent Claim
56 words
The apparatus of claim 33 wherein the said first detection means, second detection means and third detection means are a first video camera, a second video camera, and a third video camera, respectively, and wherein said first, second and third generation means is a video image processor which receives the output signals of said video cameras.
Claim 47
Dependent Claim
14 words
The apparatus of claim 44 wherein said video cameras are charge coupled device cameras.
Claim 48
Dependent Claim
91 words
The apparatus of claim 44 wherein each video camera generates a two dimensional pixel array representing the light intensity of the object detected by the camera, wherein the video image processor includes means for conducting a row-by-row evaluation of each pixel array and for determining which pixels, if any, in each row represent illumination detected on said object, and wherein the video image processor includes means for assigning to each of said pixels representing said detected illumination a precise location with respect to said support longitudinal axis and said reference plane.
Claim 49
Dependent Claim
23 words
The apparatus of claim 46 further including means in said video image processor for evaluating each pixel array by an edge detection technique.
Claim 50
Dependent Claim
27 words
The apparatus of claim 46 further including means for averaging a plurality of pixel arrays for each video camera prior to evaluation by the video image processor.
Claim 51
Dependent Claim
38 words
The apparatus of claim 46 wherein the video image processor includes means for using polynomial mathematical techniques to generate a precise curve through the pixels representing the detected illumination and corresponding to the associated surfaces of said object.
Claim 52
Dependent Claim
12 words
The apparatus of claim 29 wherein said object is a vehicle wheel.
Claim 53
Dependent Claim
13 words
The apparatus of claim 29 wherein said object is a forged aluminum wheel.
Claim 54
Dependent Claim
42 words
The apparatus of claim 30 further including means for comparing said location signals and cross section signals generated from said object with predetermined standards for said object and means for determining whether said object is within acceptable tolerances for said predetermined standards.
Claim 55
Dependent Claim
92 words
The apparatus of claim 44 wherein each video camera generates a two dimensional pixel array representing the light intensity of the object detected by the camera, wherein the video image processor includes means for conducting a column-by-column evaluation of each pixel array and for determining which pixels, if any, in each column represent said detected illumination on said object, and wherein the video image processor includes means for assigning to each of said pixels representing said detected illumination a precise location with respect to said support longitudinal axis and said reference plane.
Claim 56
Dependent Claim
23 words
The apparatus of claim 53 further including means in said video image processor for evaluating each pixel array by an edge detection technique.
Claim 57
Dependent Claim
27 words
The apparatus of claim 53 further including means for averaging a plurality of pixel arrays for each video camera prior to evaluation by the video image processor.
Claim 58
Dependent Claim
38 words
The apparatus of claim 53 wherein the video image processor includes means for using polynomial mathematical techniques to generate a precise curve through the pixels representing the detected illumination and corresponding to the associated surfaces of said object.
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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) | 2000-04-07 | 2000-10-07 | 2001-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-04-07 | 2004-10-07 | 2005-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-04-07 | 2008-10-07 | 2009-04-08 | $7700.00 | Window Closed / Lapsed |