Patent US3950981A successfully refreshed from Google Patents.
US3950981A
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Automatic system for suppressing the ground noise of apparatus for measuring the knocking
Assignee: SnamProgetti SpA
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Filing: 1974-09-23
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Granted: 1976-04-20
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Expires: 1994-09-23
Abstract
Abstract A system for automatically suppressing any ground noise present in the detection of periodic phenomena comprising detecting means for detecting the signal occurring just prior to the occurrence of the periodic phenomena, which signal is representative of ground noise, converting means for converting the sensed signal to a usable D.C. level signal, sampling means for sampling the signal resulting from the occurrence of the periodic phenomena, and summation means for algebraically adding the converted D.C. signal to the sampled signal for eliminating any ground noise present in the sampled signal, thereby providing an output signal representative of the periodic output phenomena free of any ground noise.
Inventors
- 👤 Virgilio Arrigoni
- 👤 Bruno Gaetani
- 👤 Afro Manotti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:24
CPC Classifications
G; G01; G01L; G01L23/00; G01L23/22; G01L23/221; G01L23/225; F; F02; F02P; F02P5/00; F02P5/04; F02P5/145; F02P5/15; F02P5/152; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
106 words
A system for automatically suppressing any ground noise present in the detection of periodic phenomena, comprising: detecting means for detecting the signal occurring just prior to the occurrence of the periodic phenomena which signal is representative of ground noise; converting means for converting the sensed signal to a usable D.C. level signal; sampling means for sampling the signal resulting from the occurrence of the periodic phenomena; and summation means for algebraically adding the converted D.C. signal to the sampled signal for eliminating any ground noise present in the sampled signal, thereby providing an output signal representative of the periodic output phenomena free of any ground noise.
Claim 2
Independent Claim
106 words
A system for automatically suppressing any ground noise present in the detection of periodic phenomena, comprising: detecting means for detecting the signal occurring just prior to the occurrence of the periodic phenomena which signal is representative of ground noise; converting means for converting the sensed signal to a usable D.C. level signal; sampling means for sampling the signal resulting from the occurrence of the periodic phenomena; and summation means for algebraically adding the converted D.C. signal to the sampled signal for eliminating any ground noise present in the sampled signal, thereby providing an output signal representative of the periodic output phenomena free of any ground noise.
Claim 3
Dependent Claim
38 words
The system claimed in claim 1, wherein: said summation means includes a capacitor, a rectifier, and a transistor electrically coupled to provide an output signal representing the algebraic sum of the converted D.C. signal and the sampled signal.
Claim 4
Dependent Claim
53 words
The system claimed in claim 1 in which the periodic phenomena to be detected is the knocking signal occurring in an internal combustion engine, wherein: said detection means detects the signal occurring in the interval just prior to the occurrence of the highest pressure in the operating cycle of the internal combustion engine.
Claim 5
Dependent Claim
38 words
The system claimed in claim 3, wherein: said summation means includes a capacitor, a rectifier, and a transistor electrically coupled to provide an output signal representing the algebraic sum of the converted D.C. signal and the sampled signal.
Claim 6
Dependent Claim
82 words
The system claimed in claim 3, wherein: said converting means includes a D-C restorer circuit, a bistable circuit electrically coupled to a gate, said gate being controlled by said bistable circuit, a peak voltmeter electrically coupled to said gate which is periodically resettable in response to each cycle of the internal combustion engine, and an inverter-integrator circuit for inverting and averaging the output signal from said peak voltmeter to supply a D.C. signal representative of any ground noise to said summation means.
Claim 7
Dependent Claim
38 words
The system claimed in claim 5, wherein: said summation means includes a capacitor, a rectifier, and a transistor electrically coupled to provide an output signal representing the algebraic sum of the converted D.C. signal and the sampled signal.
Claim 8
Dependent Claim
80 words
The system claimed in claim 1, wherein: said converting means includes a D.C. restorer circuit, a bistable circuit electrically coupled to a gate, said gate being controlled by said bistable circuit, a peak voltmeter electrically coupled to said gate which is periodically resettable prior to the occurrence of each periodic phenomenon, and an inverter-integrator circuit for inverting and averaging the output signal from said peak voltmeter to supply a D.C. signal representative of any ground noise to said summation means.
Claim 9
Dependent Claim
38 words
The system claimed in claim 7, wherein: said summation means includes a capacitor, a rectifier, and a transistor electrically coupled to provide an output signal representing the algebraic sum of the converted D.C. signal and the sampled signal.
References Cited (Backward Citations)
US3393557A
Cited
US3456493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-20 | 1979-10-20 | 1980-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-20 | 1983-10-20 | 1984-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-20 | 1987-10-20 | 1988-04-20 | $7700.00 | Window Closed / Lapsed |