US3863764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for identifying nonmagnetic articles
Assignee: AT&T Inc
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Filing: 1974-02-28
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Granted: 1975-02-04
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Expires: 1994-02-28
Abstract
Abstract Selected nonmagnetic semiconductor devices in an array of such devices are identified for subsequent processing by coating them with a material containing magnetizable particles. The devices are then tested to select those having the desired electrical characteristics. The selected devices in the array are contacted by the tip of a tubular marking stylus. A magnetic flux is concentrated at the tip and ink flows through stylus so that contact between the tip and article simultaneously magnetically and visibly marks the devices. Magnetic identification permits automatic sorting and removal of the selected devices from the array and the visible marking permits original set up of the array and subsequent verification of the sorting operation.
Inventors
- 👤 Stephen A Myslinski
- 👤 Edwin J Pritchard
- 👤 Howard A Tooker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:53
CPC Classifications
B; B07; B07C; B07C5/00; B07C5/34; B07C5/344
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
76 words
A method of identifying nonmagnetic articles which comprises the steps of: coating the article with a material which is capable of retaining a magnetic flux when magnetized; testing the articles individually to determine which articles are to be identified; and contacting the individual articles to be identified in accordance with the testing, with a tip of a marking member having a magnetic flux concentrated at the tip thereof to magnetize the material and identify the articles.
Claim 2
Independent Claim
76 words
A method of identifying nonmagnetic articles which comprises the steps of: coating the article with a material which is capable of retaining a magnetic flux when magnetized; testing the articles individually to determine which articles are to be identified; and contacting the individual articles to be identified in accordance with the testing, with a tip of a marking member having a magnetic flux concentrated at the tip thereof to magnetize the material and identify the articles.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein only one article is tested to determined whether it should be identified.
Claim 4
Dependent Claim
35 words
The method of claim 1 wherein a portion of the marking member is tubular and marking fluid flows through the tubular portion so that the step of contacting both visibly and magnetically identifies the articles.
Claim 5
Dependent Claim
14 words
The method of claim 3, wherein the visible and magnetic identification are accomplished simultaneously.
Claim 6
Independent Claim
77 words
A method of identifying magnetizable article which comprises the steps of; testing the articles to determine whether they have a certain characteristic; concentrating a magnetic flux at the tip of a marking member; flowing a marking fluid through the member; and placing the tip of the marking member adjacent the article to simultaneously deposit fluid on and magnetize the article having the characteristic determined in accordance with the testing, to both visibly and magnetically identify the article.
Claim 7
Independent Claim
77 words
A method of identifying magnetizable article which comprises the steps of; testing the articles to determine whether they have a certain characteristic; concentrating a magnetic flux at the tip of a marking member; flowing a marking fluid through the member; and placing the tip of the marking member adjacent the article to simultaneously deposit fluid on and magnetize the article having the characteristic determined in accordance with the testing, to both visibly and magnetically identify the article.
Claim 8
Independent Claim
102 words
A method of identifying semiconductor devices in an array which comprises the steps of: coating all the devices in the array with a material which will retain a magnetic flux when magnetized; testing the devices in the array; concentrating the flux of a permanent magnet at the tip of a marking member; flowing a marking ink through the marking member; and contacting certain devices in the array, in accordance with the testing, with the tip of the member to deposit marking fluid and simultaneously magnetize the coating material so that the selected devices are visibly and magnetically identified and identification is insured.
Claim 9
Independent Claim
102 words
A method of identifying semiconductor devices in an array which comprises the steps of: coating all the devices in the array with a material which will retain a magnetic flux when magnetized; testing the devices in the array; concentrating the flux of a permanent magnet at the tip of a marking member; flowing a marking ink through the marking member; and contacting certain devices in the array, in accordance with the testing, with the tip of the member to deposit marking fluid and simultaneously magnetize the coating material so that the selected devices are visibly and magnetically identified and identification is insured.
Claim 10
Independent Claim
112 words
A method of identifying and sorting articles form an array of the articles which comprises the steps of: coating all the articles with a material which will retain a magnetic flux; testing the articles individually to determine which articles are to be identified; concentrating a magnetic flux at the tip of a marking member; contacting the individual articles to be identified, as determined by the test, with the tip of the marking member to induce a magnetic field in the material and identify the articles; sensing the magnetic field induced in the magnetic material of the identified articles; and sorting the identified articles from the array in accordance with the magnetic field.
Claim 11
Independent Claim
112 words
A method of identifying and sorting articles form an array of the articles which comprises the steps of: coating all the articles with a material which will retain a magnetic flux; testing the articles individually to determine which articles are to be identified; concentrating a magnetic flux at the tip of a marking member; contacting the individual articles to be identified, as determined by the test, with the tip of the marking member to induce a magnetic field in the material and identify the articles; sensing the magnetic field induced in the magnetic material of the identified articles; and sorting the identified articles from the array in accordance with the magnetic field.
Claim 12
Dependent Claim
16 words
The method of claim 7 wherein the articles are beam-lead semiconductor devices in an interdigitated array.
Claim 13
Dependent Claim
33 words
The method of claim 8 wherein a portion of the marking member is tubular and marking fluid flows through the member to both visibly and magnetically identify the semiconductor devices to insure identification.
Claim 14
Dependent Claim
18 words
The method of claim 9 wherein a magnetically sensitive transistor is used to sense the induced magnetic field.
Claim 15
Dependent Claim
54 words
Apparatus for identifying nonmagnetic article having a magnetizable coating in an array such devices, which comprises: means for testing the articles while in an array to determine the characteristics thereof; and means for both inducing a magnetic field in the magnetizable coating and visibly marking the articles to insure the identification of said articles.
Claim 16
Dependent Claim
54 words
Apparatus for identifying nonmagnetic article having a magnetizable coating in an array such devices, which comprises: means for testing the articles while in an array to determine the characteristics thereof; and means for both inducing a magnetic field in the magnetizable coating and visibly marking the articles to insure the identification of said articles.
Claim 17
Dependent Claim
87 words
The apparatus of claim 11 wherein the articles are beam-lead semiconductor devices and the means for simultaneously inducing a magnetic field in the magnetizable coating material and visibly marking the device, comprises: a reservoir for marking fluid; a tubular portion extending from the reservoir, said portion being ferromagnetic and having a fluid dispensing tip smaller than then article to be identified; and magnet means adjacent the tubular portion at the tip for magnetizing the article whereby the article is simultaneously visibly and magnetically identified to insure identification.
Claim 18
Dependent Claim
67 words
A marking stylus, for identifying semiconductor devices coated with a magnetizable material, which comprises: a reservoir for marking fluid; means for conducting marking fluid from the reservoir and magnetic flux to the devices to be identified; and a magnet means for providing magnetic flux to the conducting means whereby the devices may be both visibly and magnetically marked upon contact with the conducting means to insure identification.
Claim 19
Dependent Claim
67 words
A marking stylus, for identifying semiconductor devices coated with a magnetizable material, which comprises: a reservoir for marking fluid; means for conducting marking fluid from the reservoir and magnetic flux to the devices to be identified; and a magnet means for providing magnetic flux to the conducting means whereby the devices may be both visibly and magnetically marked upon contact with the conducting means to insure identification.
Claim 20
Dependent Claim
97 words
A marking stylus according to claim 13, wherein the means for conducting marking fluid and magnetic flux, comprises: a tubular member joined at one end to the reservoir and extending horizontally therefrom to an exit end; and a ferromagneTic tubular transition member, smaller in area at the tip than the devices to be identified, which curves from a horizontal plane at the exit end of the tubular member to a vertical plane, and the bore of which is constricted at the tip of form an opening smaller than the bore to control the flow of marking fluid.
Claim 21
Dependent Claim
34 words
A marking stylus according to claim 14, wherein the magnet means is a permanent magnet which bridges the curve of the transition member and provides magnetic flux concentrated at the tip of said member.
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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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |