US3786675A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable gas leak detector
Assignee: USON CORP
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Filing: 1970-11-23
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Granted: 1974-01-22
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Expires: 1990-11-23
Abstract
Abstract In a portable gas leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings and having a conductivity detector, first amplifier and output, the improvement of a positive and a negative drive amplifier connected to the first amplifier with separate indicating lights connected to each of the positive and negative drive amplifiers for indicating the relative conductivity of the sample to the ambient surroundings and whether the detector is approaching or leaving a leak. A feedback loop connected across the first amplifier which includes an amplifier having a memory retaining means for zeroing the output for overcoming temperature induced drift in the detector and nulling the output of the detector thereby allowing accurate pinpointing of the leak. Means for actuating the feedback loop including a manual switch, an automatic switch when the output is less than a predetermined amount, and an automatic switching means when the output is more than a predetermined amount for a certain period of time.
Inventors
- 👤 L Delatorre
- 👤 W Rapson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:14
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/002; G01M3/02; G01M3/04; G01M3/20; G01M3/202; G01M3/205; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/14; G01N27/18
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
159 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including automatic switching means for actuating the feedback loop when the output is less than a predetermined amount.
Claim 2
Dependent Claim
159 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including automatic switching means for actuating the feedback loop when the output is less than a predetermined amount.
Claim 3
Dependent Claim
165 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including automatic switching means for actuating the feedback loop when the output is more than a predetermined amount for a predetermined period of time.
Claim 4
Dependent Claim
165 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including automatic switching means for actuating the feedback loop when the output is more than a predetermined amount for a predetermined period of time.
Claim 5
Dependent Claim
170 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including a manual switch and including automatic switching means for actuating the feedback loop when the output is more than a predetermined amount for a predetermined period of time.
Claim 6
Dependent Claim
170 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, and a first amplifier connected to the gas detector and having an output, the improvement comprising, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected across the first amplifier including an amplifier having memory-retaining means whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and means for actuating said feedback loop including a manual switch and including automatic switching means for actuating the feedback loop when the output is more than a predetermined amount for a predetermined period of time.
Claim 7
Dependent Claim
31 words
The apparatus of claim 3 wherein the means for actuating said feedback loop includes automatic switching means for actuating the feedback loop when the output is less than a predetermined amount.
Claim 8
Dependent Claim
202 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, first amplifier and output, the improvement comprising, a positive drive amplifier and a negative drive amplifier each connected to the first amplifier, a separate indicating light connected to each of the positive and negative drive amplifiers, a feedback loop connected across the first amplifier including a second amplifier having a memory retaining means connected across the second amplifier whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means and nulls the output from the first ampLifier, and nulls both of the indicating lights, a manual switch for actuating said feedback loop thereby nulling the current gas measurement indicated by the indicating lights whereby further movement of the detector in the vicinity of the leak will actuate one or the other indicating light showing whether the detector is approaching or leaving the leak thereby allowing the detector to pin-point the leak by actuating the manual switch during movement of the detector.
Claim 9
Dependent Claim
202 words
In a leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas and having a gas detector, first amplifier and output, the improvement comprising, a positive drive amplifier and a negative drive amplifier each connected to the first amplifier, a separate indicating light connected to each of the positive and negative drive amplifiers, a feedback loop connected across the first amplifier including a second amplifier having a memory retaining means connected across the second amplifier whereby said loop when actuated holds the measurement level of the first amplifier in the memory-retaining means and nulls the output from the first ampLifier, and nulls both of the indicating lights, a manual switch for actuating said feedback loop thereby nulling the current gas measurement indicated by the indicating lights whereby further movement of the detector in the vicinity of the leak will actuate one or the other indicating light showing whether the detector is approaching or leaving the leak thereby allowing the detector to pin-point the leak by actuating the manual switch during movement of the detector.
Claim 10
Dependent Claim
34 words
The apparatus of claim 5 wherein the means for actuating said feedback loop includes automatic switching means for actuating the feedback loop when the output of said amplifier is less than a predetermined amount.
Claim 11
Dependent Claim
41 words
The apparatus of claim 6 wherein the means for actuating said feedback loop includes automatic switching means for actuating the feedback loop when the output of the first amplifier is more than a predetermined amount for a predetermined period of time.
Claim 12
Dependent Claim
219 words
A leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas thereby locating the leak comprising, a gas detector, a first amplifier connected to the output of the gas detector, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected between the output and the input of the first amplifier said feedback loop including a second amplifier and a memory retaining means connected across the second amplifier whereby said loop when actuated holds the measurement level of the first amplifier in the memory retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and a manual switch for actuating said feedback loop as the detector is moved in the vicinity of a leak for nulling the gas measurement indicated by the polarity indicating means whereby on further movement of the detector any actuation of the positive polarity indicating means or negative polarity indicating means will indicate whether the detector is approaching or leaving a leak thereby allowing the detector to pinpoint the leak.
Claim 13
Dependent Claim
219 words
A leak detector for determining the location of leaks of gases having a different thermal conductivity than the ambient surroundings by moving the detector in the vicinity of a leak and detecting the increase or decrease of leaking gas thereby locating the leak comprising, a gas detector, a first amplifier connected to the output of the gas detector, a positive polarity indicating means connected to the output of the first amplifier, a negative polarity indicating means connected to the output of the first amplifier, a feedback loop connected between the output and the input of the first amplifier said feedback loop including a second amplifier and a memory retaining means connected across the second amplifier whereby said loop when actuated holds the measurement level of the first amplifier in the memory retaining means thereby nulling the output from the first amplifier and nulling both of the polarity indicating means, and a manual switch for actuating said feedback loop as the detector is moved in the vicinity of a leak for nulling the gas measurement indicated by the polarity indicating means whereby on further movement of the detector any actuation of the positive polarity indicating means or negative polarity indicating means will indicate whether the detector is approaching or leaving a leak thereby allowing the detector to pinpoint the leak.
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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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |