US4415980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automated radiographic inspection system
Assignee: Lockheed Martin Corp
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Filing: 1981-03-02
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Granted: 1983-11-15
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Expires: 2001-03-02
Abstract
Abstract In an automated real-time radiographic inspection system for detecting flaws, defects or inhomogeneities in manufactured objects, the objects (10, 11, 12, . . . ) to be tested are moved on a conveyor (20) in succession past an X-ray source (30). Penetrating X-ray radiation is transmitted through the objects (10, 11, 12, . . . ) to cause an image to be formed for each object in succession by an electronic imaging system (40). The imaging system (40) generates digital signals representative of the image for each object, and transmits the digital signals to a data processor/comparator (50). One of the objects (10, 11, 12, . . . ) may be considered as a reference object against which the other objects are compared for structural homogeneity. Thus, the electronic images of the objects (11, 12, . . . ) could be compared with the electronic image of, for example, the object (10). Alternatively, the electronic images of the test objects could be compared with an electronic reference image programmed into the data processor/comparator (50), the programmed reference image. The comparison performed by the data processor/comparator (50) is a subtraction process, which eliminates background features common to test and reference images. Thus, any flaw appearing in a test image, but not present in the reference image, stands out in sharp detail. When a flaw occurs in a test image, the subtractive process results in a non-null signal, which activates a conveyor control mechanism (70) for stopping the conveyor (20) so as to enable rejection of the flawed test object.
Inventors
- 👤 Robert A. Buchanan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:16
CPC Classifications
G; G01; G01N; G01N23/00; G01N23/02; G01N23/06; G01N23/18; G01N23/083; G06; G06T; G06T7/00; G06T7/0002; G06T7/0004; G06T7/001; G06T2207/00; G06T2207/10; G06T2207/10116; G06T2207/20; G06T2207/20212; G06T2207/20224; G06T2207/30; G06T2207/30108; G06T2207/30164
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
115 words
A method of determining structural conformity of a test object to a reference object for quality control of manufactured objects, said method comprising the steps of: (a) transmitting X-ray radiation through said reference object to phosphor means for generating an optical signal, which is converted to an electronic image of said reference object; (b) transmitting x-ray radiation through said test object to phosphor means for generating an optical signal, which is converted to an electronic image of said test object; and (c) subtracting one of the aforesaid electronic images from the other to produce a subtractive image in which any significant structural difference between said test object and said reference object appears in sharp detail.
Claim 2
Independent Claim
115 words
A method of determining structural conformity of a test object to a reference object for quality control of manufactured objects, said method comprising the steps of: (a) transmitting X-ray radiation through said reference object to phosphor means for generating an optical signal, which is converted to an electronic image of said reference object; (b) transmitting x-ray radiation through said test object to phosphor means for generating an optical signal, which is converted to an electronic image of said test object; and (c) subtracting one of the aforesaid electronic images from the other to produce a subtractive image in which any significant structural difference between said test object and said reference object appears in sharp detail.
Claim 3
Dependent Claim
42 words
The method of claim 1 wherein said electronic images of said reference and test objects are digitized representations of said reference and test objects, and wherein the subtracting of one of said electronic images from the other is performed by computer means.
Claim 4
Dependent Claim
48 words
The method of claim 2 wherein the electronic image of said reference object is stored in a memory device, and the electronic image of said test object is compared with said image of said reference object by a process wherein one said images is subtracted from the other.
Claim 5
Dependent Claim
69 words
The method of claim 1 wherein a separate electronic image is formed of each one of a plurality of test objects, and wherein a control signal is generated whenever any significant difference appears between a particular one of the test objects and said reference object, said control signal activating means for rejecting said particular one of said test objects as not being in structural conformity with said reference object.
Claim 6
Independent Claim
120 words
A method of detecting a substantial inhomogeneity in a test object, said method comprising the sequential steps of: (a) forming a first image of said test object by causing penetrating electromagnetic radiation from a radiation source to pass through said test object and impinge upon a detector; (b) causing displacement of one relative to another of said radiation source, test object and detector; (c) forming a second image of said test object by causing penetrating electromagnetic radiation from said radiation source to pass through said test object and impinge upon said detector; and (d) subtracting one of said first and second images from the other to produce a subtractive mage in which any substantial inhomogeneity in said test object appears.
Claim 7
Independent Claim
120 words
A method of detecting a substantial inhomogeneity in a test object, said method comprising the sequential steps of: (a) forming a first image of said test object by causing penetrating electromagnetic radiation from a radiation source to pass through said test object and impinge upon a detector; (b) causing displacement of one relative to another of said radiation source, test object and detector; (c) forming a second image of said test object by causing penetrating electromagnetic radiation from said radiation source to pass through said test object and impinge upon said detector; and (d) subtracting one of said first and second images from the other to produce a subtractive mage in which any substantial inhomogeneity in said test object appears.
Claim 8
Dependent Claim
33 words
The method of claim 5 wherein a control signal is generated whenever any inhomogeneity in said test object appears in said subtractive image, said control signal activating means for rejecting said test object.
Claim 9
Dependent Claim
25 words
The method of claim 5 wherein said test object is moved relative to said radiation source and detector after said first image has been formed.
Claim 10
Dependent Claim
53 words
The method of claim 7 wherein said first and second images are formed by causing X-ray radiation that has passed through said test object to impinge upon phosphor means for generating corresponding first and second optical signals, and by converting said optical signals to digital electronic signals constituting said first and second images.
Claim 11
Dependent Claim
54 words
The method of claim 8 wherein digital signal constituting said first image are stored in a memory device, and digital signals constituting said second image are compared with said digital signals constituting said first image by a process wherein one of said first and second images is subtracted from the other by computer means.
Claim 12
Independent Claim
117 words
A system for determining structural conformity of a test object to a reference object for quality control of manufactured objects, said system comprising: (a) means for transmitting X-ray radiation through said reference object to phosphor means for generating an optical signal, which is converted to an electronic image of said reference object; (b) means for transmitting X-ray radiation through said test object to phosphor means for generating an optical signal, which is converted to an electronic image of said test object; and (c) means for subtracting one of said electronic images from the other to produce a subtractive image in which any significant structural difference between said test object and said reference object appears in sharp detail.
Claim 13
Independent Claim
117 words
A system for determining structural conformity of a test object to a reference object for quality control of manufactured objects, said system comprising: (a) means for transmitting X-ray radiation through said reference object to phosphor means for generating an optical signal, which is converted to an electronic image of said reference object; (b) means for transmitting X-ray radiation through said test object to phosphor means for generating an optical signal, which is converted to an electronic image of said test object; and (c) means for subtracting one of said electronic images from the other to produce a subtractive image in which any significant structural difference between said test object and said reference object appears in sharp detail.
Claim 14
Independent Claim
124 words
A system for detecting a substantial inhomogeneity in a test object, said system comprising: (a) means for forming a first image of said test object by causing penetrating electromagnetic radiation from a radiation source to pass through said test object and impinge upon a detector; (b) means for causing displacement of one relative to another of said radiation source, test object and detector; (c) means for forming a second image of said test object by causing penetrating electromagnetic radiation from said radiation source to pass through said test object and impinge upon said detector; and (d) means for subtracting one of said first and second images from the other to produce a subtractive image in which any substantial inhomogeneity in said test object appears.
Claim 15
Independent Claim
124 words
A system for detecting a substantial inhomogeneity in a test object, said system comprising: (a) means for forming a first image of said test object by causing penetrating electromagnetic radiation from a radiation source to pass through said test object and impinge upon a detector; (b) means for causing displacement of one relative to another of said radiation source, test object and detector; (c) means for forming a second image of said test object by causing penetrating electromagnetic radiation from said radiation source to pass through said test object and impinge upon said detector; and (d) means for subtracting one of said first and second images from the other to produce a subtractive image in which any substantial inhomogeneity in said test object appears.
References Cited (Backward Citations)
US3673394A
Cited
US3588502A
Cited
US4024225A
Cited
US3988602A
Cited
US4092537A
Cited
US4056716A
Cited
US4323973A
Cited
US4335427A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-14 | 1987-05-16 | 1987-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-14 | 1991-05-16 | 1991-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-14 | 1995-05-16 | 1995-11-15 | $7700.00 | Window Closed / Lapsed |