US4853619A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital panel meter
Assignee: RT ENGINEERING SERVICE Inc 65 MAPLE STREET MANSFIELD MASSACHUSETTS A MA CORP
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Filing: 1988-02-17
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Granted: 1989-08-01
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Expires: 2008-02-17
Abstract
Abstract A digital panel meter adapted for replacement of a standard analog panel meter and designed to selectively receive different ranges of input signals such as AC or DC input signals. The meter circuitry employs an analog-to-digital converter having multiple digits, an input circuit including a range circuit, an operational amplifier and filter circuitry. A relay is tripped for signaling the attaining of a trip point. An audible alarm is provided that may be enabled or disabled and that may be operated in either continuous or short term modes.
Inventors
- 👤 Brian Paulsen
- 👤 Joseph Vignolo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:04
CPC Classifications
G; G01; G01R; G01R13/00; G01R13/02; G01R15/00; G01R15/08; G01R15/09
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
192 words
A digital panel meter comprising; a housing, input terminals means for receiving AC and DC input signals, range circuit means including means responsive to the output of the input terminal means and means for selecting one of a plurality of different amplitude ranges, amplifier means responsive to the output of the range circuit means and having an output, a rectifier means responsive to the output of the amplifier means, filter means responsive to the output of the rectifier means, analog-to-digital converter means responsive to the filter means, display means mounted in the housing and coupled from said analog-to-digital converter means, a terminal strip at the rear of the housing including terminals forming the input terminal means and AC power terminals, a comparator means responsive to the output of the filter means, means for establishing an adjustable reference input to the comparator means for establishing a trip-point, relay means coupled from the output of said comparator means and adapted to be set when the comparator means triggers, and a plurality of separately operable decimal point setting switches coupled to said display means for manual setting of the decimal point in the display means.
Claim 2
Dependent Claim
192 words
A digital panel meter comprising; a housing, input terminals means for receiving AC and DC input signals, range circuit means including means responsive to the output of the input terminal means and means for selecting one of a plurality of different amplitude ranges, amplifier means responsive to the output of the range circuit means and having an output, a rectifier means responsive to the output of the amplifier means, filter means responsive to the output of the rectifier means, analog-to-digital converter means responsive to the filter means, display means mounted in the housing and coupled from said analog-to-digital converter means, a terminal strip at the rear of the housing including terminals forming the input terminal means and AC power terminals, a comparator means responsive to the output of the filter means, means for establishing an adjustable reference input to the comparator means for establishing a trip-point, relay means coupled from the output of said comparator means and adapted to be set when the comparator means triggers, and a plurality of separately operable decimal point setting switches coupled to said display means for manual setting of the decimal point in the display means.
Claim 3
Dependent Claim
25 words
A digital panel meter as set forth is claim 1 wherein said amplifier means includes an operational amplifier and said rectifier means includes a diode.
Claim 4
Dependent Claim
33 words
A digital panel meter as set forth in claim 2 wherein said range circuit means includes a plurality of different value scaling resistors each coupling to a signal input of the operational amplifier.
Claim 5
Dependent Claim
27 words
A digital panel meter as set forth in claim 3 wherein said means for selecting includes a jumper selectively coupled to only one of said scaling resistors.
Claim 6
Dependent Claim
24 words
A digital panel meter as set forth in claim 4 including a pair of oppositely poled diodes across the input of the operational amplifier.
Claim 7
Dependent Claim
19 words
A digital panel meter as set forth in claim 5 wherein said filter means includes a resistor-capacitor ladder network.
Claim 8
Dependent Claim
24 words
A digital panel meter as set forth in claim 6 including a scale potentiometer across the operational amplifier for calibration purposes of the display.
Claim 9
Dependent Claim
23 words
A digital panel meter as set forth in claim 1 including a diode connected between the input and output of the amplifier means.
Claim 10
Dependent Claim
46 words
A digital panel meter as set forth in claim 1 wherein said range circuit means include a plurality of different value scaling resistors, said means for selecting including a jumper selectively coupled to one of said scaling resistors, said terminal strip including terminals for said jumper.
Claim 11
Dependent Claim
25 words
A digital panel meter as set forth in claim 1 including means for providing an audible alarm in response to the setting of said relay.
Claim 12
Dependent Claim
19 words
A digital panel meter as set forth in claim 10 including first switch means for enabling said audible alarm.
Claim 13
Dependent Claim
28 words
A digital panel meter as set forth in claim 11 including a second switch means for selecting between either continuous alarm or an alarm of predetermined short duration.
Claim 14
Dependent Claim
39 words
A digital panel meter as set forth in claim 1 including a first switch associated with said comparator means and means for adjusting the trip-point, said switch providing for direct coupling of the set-point adjustment to the display means.
Claim 15
Dependent Claim
28 words
A digital panel meter as set forth in claim 13 including a second switch for disabling the relay when the first switch is used to set the trip-point.
Claim 16
Dependent Claim
161 words
A digital panel meter comprising: a housing; a terminal strip associated with the housing and including input terminal means; range circuit means including means coupled from the input terminal means and means for selecting one of a plurality of different amplitude ranges; detection circuit means including amplifier means coupled from said range circuit means and having a detection circuit means output; analog-to-digital converter means coupled from said detection circuit means; display means mounted in the housing and coupled from said analog-to-digital converter means; a comparator means responsive to the output of said detection circuit means, and means for establishing an adjustable reference input to the comparator means for establishing a trip-point; means coupled from the output of said comparator means and adapted to be set when the comparator means triggers; decimal point setting switch means coupled to said display means and including means for manually setting one of a plurality of different settings of the decimal point in the display means.
Claim 17
Dependent Claim
161 words
A digital panel meter comprising: a housing; a terminal strip associated with the housing and including input terminal means; range circuit means including means coupled from the input terminal means and means for selecting one of a plurality of different amplitude ranges; detection circuit means including amplifier means coupled from said range circuit means and having a detection circuit means output; analog-to-digital converter means coupled from said detection circuit means; display means mounted in the housing and coupled from said analog-to-digital converter means; a comparator means responsive to the output of said detection circuit means, and means for establishing an adjustable reference input to the comparator means for establishing a trip-point; means coupled from the output of said comparator means and adapted to be set when the comparator means triggers; decimal point setting switch means coupled to said display means and including means for manually setting one of a plurality of different settings of the decimal point in the display means.
References Cited (Backward Citations)
US3979657A
Cited
US4000463A
Cited
US4115733A
Cited
US4157501A
Cited
US4251769A
Cited
GB2055480A
Cited
US4321530A
Cited
US4422039A
Cited
US4748404A
Cited
US4641090A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-31 | 1993-01-30 | 1993-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-31 | 1997-01-30 | 1997-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-31 | 2001-01-30 | 2001-08-01 | $7700.00 | Window Closed / Lapsed |