US 5,619,587 AGranted

System and method for contactlessly gauging the thickness of a contoured object, such as a vehicle wheel

AssigneeAluminum Company of America

InventorsLouis G. Willoughby, Jr., Donald G. Jordan, Paul R. Adomaitis, Avraham C. Goldman, Anthony J. Tomasello, Steve Montellese, Edward W. Weed, Abraham Shtrahman

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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.

Claims56

Dependent claims

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.

4 more elements

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.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/166,891Filed 15 Dec 1993 · continuation
Priority: 10 May 1991
Granted: 8 Apr 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

B21C 51/00
Measuring, gauging, indicating, counting, or marking devices specially adapted for use in
G01B 11/245
For measuring contours or curvatures: using a plurality of fixed, simultaneously operating transducers
B21C
Manufacture of metal sheets, wire, rods, tubes, profiles or like semi-manufactured products
G01B
Measuring length, thickness or similar linear dimensions