US3681758A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data acquisition unit with memory
Assignee: Northrop Grumman Corp
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Filing: 1970-04-29
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Granted: 1972-08-01
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Expires: 1990-04-29
Abstract
Abstract A small automatic test system having input connections for a multiplicity of test points from an outside system to be tested. This test unit rapidly scans through the test points and measures the voltage value at each point as compared to a predetermined tolerance range recorded in the test system memory, giving a GO and NO GO type of display along with the measured value and the corresponding test point number of a NO GO measurement. The limits defining the tolerance range for each test point measurement are loaded into the memory from a magnetic tape unit or from a manual loader, which units are parts of the present test system. The tape may be pre-recorded or made up on the test system itself. Operating speed of the system is over 2500 test points per second.
Inventors
- 👤 Stanley Oster
- 👤 Herbert I Higashi
- 👤 Otto Dorner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:03
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/28; G01R31/317; G01R31/3181; G01R31/319; G01R31/3193
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
218 words
Apparatus for automatically monitoring signals at a plurality of test points of a system to be tested, comprising multiplexer means for selectively coupling test point signals at a plurality of input connections to a single output, analog-to-digital converter means connected to the output of said multiplexer means for converting said signals to digital data, memory means for storing tolerance limit data for signals at said test points, respectively, comparator means for comparing the digital data output of said converter means with stored tolerance limit data, scanning means connected to said multiplexer means and to said memory means for causing said multiplexer means to couple test point signals from said input connections to said converter means in sequence and for causing said memory means to feed tolerance limit data to said comparator means synchronized with corresponding digital data fed to said comparator means from said converter means, and at a sequencing rate at least of the order of several hundred to a thousand test points per second, detector means connected to the output of said comparator means for determining whether a signal is within tolerance or out of tolerance, and display means connected to the output of said detector means for producing a GO condition or a NO GO condition depending upon the respective determinations by said detector means.
Claim 2
Dependent Claim
218 words
Apparatus for automatically monitoring signals at a plurality of test points of a system to be tested, comprising multiplexer means for selectively coupling test point signals at a plurality of input connections to a single output, analog-to-digital converter means connected to the output of said multiplexer means for converting said signals to digital data, memory means for storing tolerance limit data for signals at said test points, respectively, comparator means for comparing the digital data output of said converter means with stored tolerance limit data, scanning means connected to said multiplexer means and to said memory means for causing said multiplexer means to couple test point signals from said input connections to said converter means in sequence and for causing said memory means to feed tolerance limit data to said comparator means synchronized with corresponding digital data fed to said comparator means from said converter means, and at a sequencing rate at least of the order of several hundred to a thousand test points per second, detector means connected to the output of said comparator means for determining whether a signal is within tolerance or out of tolerance, and display means connected to the output of said detector means for producing a GO condition or a NO GO condition depending upon the respective determinations by said detector means.
Claim 3
Dependent Claim
31 words
Apparatus in accordance with claim 1, further comprising means including a recorder for recording tolerance limit data, said recorder having playback means for inserting recorded limit data into said memory means.
Claim 4
Dependent Claim
51 words
Apparatus in accordance with claim 2, wherein said recorder comprises means for recording a plurality of sets of tolerance limit data and index means for selecting any desired set of recorded limit data, and wherein said playback means is responsive to the set of limit data Selected by said index means.
Claim 5
Dependent Claim
37 words
Apparatus in accordance with claim 1, further comprising manual means for inserting tolerance limit data into said memory means, one test point at a time, at locations in said memory means corresponding to the respective test points.
Claim 6
Dependent Claim
29 words
Apparatus in accordance with claim 4, further comprising means for recording tolerance limit data, and means for inserting the limit data from said memory means into said recording means.
Claim 7
Dependent Claim
38 words
Apparatus in accordance with claim 1, further comprising display means for indicating the magnitude of a signal at a test point and display means for indicating the identification of a test point corresponding to a NO GO determination.
Claim 8
Dependent Claim
67 words
Apparatus in accordance with claim 1, wherein said memory means has means for storing low tolerance limit data and high tolerance limit data for said test point signals, and further comprising display means for selectively indicating any one of the low tolerance limit data, high tolerance limit data, and signal magnitude for any selected test point and display means for indicating the identification of the test point.
Claim 9
Dependent Claim
23 words
Apparatus in accordance with claim 1, further comprising means for causing said display means to indicate NO GO determinations, if any, in sequence.
Claim 10
Dependent Claim
61 words
Apparatus in accordance with claim 1, wherein said memory means comprises a dynamic register electronic memory, means including a magnetic tape recorder unit for recording tolerance limit data, said tape recorder unit having tape playback means for inserting said limit data into said memory means, and means for automatically reducing the sequencing rate of said scanning means during the inserting operation.
Claim 11
Dependent Claim
68 words
Apparatus in accordance with claim 1, wherein said memory means comprises a pair of dynamic register electronic memories operating in parallel for storing, respectively, high tolerance limit data of each test point and low tolerance limit data of each test point, said scanning means comprising means for simultaneously feeding limit data from each memory to said comparator means along with the corresponding digital data from said converter means.
Claim 12
Dependent Claim
103 words
Apparatus in accordance with claim 1, wherein said memory means comprises a pair of memory units operating in parallel for storing, respectively, high tolerance limit data and low tolerance limit data corresponding to each test point, and means including a magnetic tape recorder for recording all test point high limit data in series with all test point low limit data, said recorder having playback means for inserting the recorded limit data into said memory means, said playback means including separator means for inserting high limit data into one of said memory units and then inserting low limit data into the other memory unit.
Claim 13
Dependent Claim
121 words
Apparatus in accordance with claim 1, wherein the system to be tested has, for at least a certain test point, a controllable device for changing the signal at such test point, and further comprising additional multiplexer means for connecting said detector means selectively to any one of a plurality of lines corresponding to test points, means for operating said additional multiplexer means in synchronism with the first-mentioned multiplexer means, means connected to the lines of said additional multiplexer means corresponding to said certain test points for producing a steady error signal in response to an out of tolerance determination by said detector means, and actuator means responsive to said error signal for operating said controllable device to reduce said error signal.
Claim 14
Dependent Claim
110 words
Apparatus in accordance with claim 1, wherein the system to be tested has, for at least a certain test point, a controllable device for changing the signal at such test point, and further comprising additional multiplexer means for connecting said detector means to any one of a plurality of lines corresponding to test points, means for operating said additional multiplexer means in synchronism with the first-mentioned multiplexer mEans, and a servo-mechanism having its input connected to a line corresponding to said certain test point and its output connected to said controllable device for adjusting said device in a direction to eliminate an out of tolerance determination by said detector means.
Claim 15
Dependent Claim
20 words
Apparatus in accordance with claim 1, there being a plurality of such controllable devices and servo-mechanisms for corresponding test points.
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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) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |