US3580081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum gauge
Assignee: VEECO INSTRUMENTS ACQUISITION CORP
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Filing: 1969-09-10
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Granted: 1971-05-25
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Expires: 1989-09-10
Abstract
Abstract Disclosed herein is a Pirani-type pressure gauge having a sensor head incorporating a pressure-responsive filament, a calibrated pressure indicator, and related circuitry for converting the voltage drop across the filament into a meaningful pressure indication. The net current supplied to the filament includes both an energizing component and an indicator drive component. This net current is maintained constant by a constant current source so that, excluding ambient temperature affects, the voltage across the filament is indicative of filament resistance and consequently ambient pressure, notwithstanding the effect of the indicator. Temperature effects are minimized by a simple compensating impedance in the filament-indicator circuit which also includes scale-calibration controls and means for shaping filament response. The calibration, compensation, and shaping components are located in the filament sensor head in such a manner as to obviate the usual field adjustments required to match the sensor head and indicator.
Inventors
- 👤 Sol Greenberg
- 👤 Heinz Rosen
- 👤 Richard Weinberger
- 👤 Guy Mongodin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:13
CPC Classifications
G; G01; G01L; G01L21/00; G01L21/10; G01L21/12
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
46 words
A Pirani-type gauge having a pressure-sensitive filament, indicator means, and means for supplying said filament with the combination of energizing current and current flowing through said indicator means, said supply means comprising a constant current source for maintaining constant said combined currents flowing through said filament.
Claim 2
Dependent Claim
46 words
A Pirani-type gauge having a pressure-sensitive filament, indicator means, and means for supplying said filament with the combination of energizing current and current flowing through said indicator means, said supply means comprising a constant current source for maintaining constant said combined currents flowing through said filament.
Claim 3
Dependent Claim
51 words
Apparatus as defined in claim 1 in which said pressure-sensitive filament is located in a sensing head remote from said indicator means and including means in said head for matching said filament to said indicator means whereby a new head and filament may be substituted without the need for new calibration.
Claim 4
Dependent Claim
9 words
means for supplying energizing current to said filament means,
Claim 5
Dependent Claim
9 words
means for supplying energizing current to said filament means,
Claim 6
Dependent Claim
11 words
a second terminal point electrically coupled in series with said filament;
Claim 7
Dependent Claim
11 words
a second terminal point electrically coupled in series with said filament;
Claim 8
Dependent Claim
13 words
a first and a second voltage divider network coupled across said converting means;
Claim 9
Dependent Claim
13 words
a first and a second voltage divider network coupled across said converting means;
Claim 10
Dependent Claim
27 words
Apparatus as defined in claim 1 in which said indicator means comprises a meter operable in response to said current flowing therethrough without the need for amplification.
Claim 11
Dependent Claim
14 words
measuring means connected to said filament means for indicating data related to said pressure,
Claim 12
Dependent Claim
14 words
measuring means connected to said filament means for indicating data related to said pressure,
Claim 13
Dependent Claim
25 words
said measuring means being interconnected with said filament means whereby the net current through said filament means includes the effect of said measuring means, and
Claim 14
Dependent Claim
25 words
said measuring means being interconnected with said filament means whereby the net current through said filament means includes the effect of said measuring means, and
Claim 15
Dependent Claim
24 words
Apparatus as defined in claim 1 including a filament circuit containing said filament and response-shaping means for midi modifying the response of said filament.
Claim 16
Dependent Claim
173 words
a first electrical path coupling said first terminal point to said second terminal point for the carrying of A portion of said current of constant magnitude, the magnitude of said portion of current varying in a direct relationship to the resistance of said filament wherein said first electrical path comprises: i. a first transistor having an emitter, a collector and a base, said collector being coupled to said first terminal point, said emitter being coupled to a third terminal point having a constant magnitude of voltage impressed upon it and said base being coupled to said first voltage divider network, wherein the magnitude of current flowing into the collector of said first transistor effectively flows to said third terminal point; ii. an indicator having one of its two terminals coupled in series with said third terminal point; iii. a first potentiometer having one of its two terminals coupled in series with the free terminal of said indicator and the other terminal of said first potentiometer coupled in series to said second terminal point;
Claim 17
Dependent Claim
173 words
a first electrical path coupling said first terminal point to said second terminal point for the carrying of A portion of said current of constant magnitude, the magnitude of said portion of current varying in a direct relationship to the resistance of said filament wherein said first electrical path comprises: i. a first transistor having an emitter, a collector and a base, said collector being coupled to said first terminal point, said emitter being coupled to a third terminal point having a constant magnitude of voltage impressed upon it and said base being coupled to said first voltage divider network, wherein the magnitude of current flowing into the collector of said first transistor effectively flows to said third terminal point; ii. an indicator having one of its two terminals coupled in series with said third terminal point; iii. a first potentiometer having one of its two terminals coupled in series with the free terminal of said indicator and the other terminal of said first potentiometer coupled in series to said second terminal point;
Claim 18
Dependent Claim
107 words
a second electrical path additionally coupling said first terminal point to said second terminal point for the carrying of said current of constant magnitude not flowing through said first electrical path wherein a second transistor having an emitter, a collector and a base is coupled within said second path having said emitter coupled to said first terminal point, said collector coupled to said second terminal point and said base coupled to said second voltage divider network the magnitude of current appearing at said emitter being effectively applied to said second terminal points; and e. a second potentiometer coupled between said sensing filament and said second terminal point.
Claim 19
Dependent Claim
107 words
a second electrical path additionally coupling said first terminal point to said second terminal point for the carrying of said current of constant magnitude not flowing through said first electrical path wherein a second transistor having an emitter, a collector and a base is coupled within said second path having said emitter coupled to said first terminal point, said collector coupled to said second terminal point and said base coupled to said second voltage divider network the magnitude of current appearing at said emitter being effectively applied to said second terminal points; and e. a second potentiometer coupled between said sensing filament and said second terminal point.
Claim 20
Dependent Claim
5 words
A Pirani-type pressure gauge comprising:
Claim 21
Dependent Claim
5 words
A Pirani-type pressure gauge comprising:
Claim 22
Dependent Claim
12 words
regulator means responsive to said net current for maintaining same substantially constant.
Claim 23
Dependent Claim
12 words
regulator means responsive to said net current for maintaining same substantially constant.
Claim 24
Dependent Claim
44 words
Apparatus as defined in claim 5 including a sensing unit containing said filament means and remote from said supply means and measuring means, said sensing unit including calibration means in circuit with said filament means for matching said filament means to said measuring means.
Claim 25
Dependent Claim
23 words
Apparatus as defined in claim 5 in which said filament means includes pressure-sensitive filament and means for modifying the response of said filament.
Claim 26
Dependent Claim
28 words
Apparatus as defined in claim 5 in which said measuring means includes a reference potential for comparison with a signal responsive to the condition of said filament means.
Claim 27
Dependent Claim
57 words
In a Pirani-type pressure-measuring instrument having a sensing head containing a filament for developing a signal indicative of ambient pressure, and a remote measuring circuit for measuring said signal, the improvement comprising means in said sensing head for matching said filament to said measuring circuit thereby facilitating replacement of said head and filament without further matching adjustments.
Claim 28
Dependent Claim
57 words
In a Pirani-type pressure-measuring instrument having a sensing head containing a filament for developing a signal indicative of ambient pressure, and a remote measuring circuit for measuring said signal, the improvement comprising means in said sensing head for matching said filament to said measuring circuit thereby facilitating replacement of said head and filament without further matching adjustments.
Claim 29
Dependent Claim
15 words
Apparatus as defined in claim 9 in which said matching means comprises variable resistance means.
Claim 30
Dependent Claim
23 words
Apparatus as defined in claim 9 in which said matching means comprises means for adjusting said signal under minimum and maximum pressure conditions.
Claim 31
Dependent Claim
59 words
In a Pirani-type pressure-measuring instrument having a sensing head containing a filament for developing a signal indicative of ambient pressure, and a remote measuring circuit for measuring said signal and wherein said filament communicates with the pressure to be sensed, the improvement comprising means resiliently gripping said filament in sealing relationship whereby the replacement of said filament is simplified.
Claim 32
Dependent Claim
59 words
In a Pirani-type pressure-measuring instrument having a sensing head containing a filament for developing a signal indicative of ambient pressure, and a remote measuring circuit for measuring said signal and wherein said filament communicates with the pressure to be sensed, the improvement comprising means resiliently gripping said filament in sealing relationship whereby the replacement of said filament is simplified.
Claim 33
Dependent Claim
141 words
A pressure gauge comprising: a. a source of potential; b. means for converting said source of potential into a direct current source of constant magnitude; c. a sensing filament whose resistance varies in a direct relationship to the pressure of an environment into which said sensing filament has been placed wherein said sensing filament is electrically coupled to said current of constant magnitude; d. circuitry between said means for converting said source of potential into a direct current source of constant magnitude and said sensing filament wherein the input and output magnitudes of the current supplied to and flowing from said circuitry does not vary and wherein the value of said filament resistance affects the flow of current within said circuitry so as to provide for a meaningful measurement of the pressure of the environment surrounding said filament, said circuitry comprising:
Claim 34
Dependent Claim
141 words
A pressure gauge comprising: a. a source of potential; b. means for converting said source of potential into a direct current source of constant magnitude; c. a sensing filament whose resistance varies in a direct relationship to the pressure of an environment into which said sensing filament has been placed wherein said sensing filament is electrically coupled to said current of constant magnitude; d. circuitry between said means for converting said source of potential into a direct current source of constant magnitude and said sensing filament wherein the input and output magnitudes of the current supplied to and flowing from said circuitry does not vary and wherein the value of said filament resistance affects the flow of current within said circuitry so as to provide for a meaningful measurement of the pressure of the environment surrounding said filament, said circuitry comprising:
Claim 35
Dependent Claim
138 words
A pressure gauge as described in claim 13 wherein said filament is contained within a sensor head electrically detachably coupled to said indicator wherein said sensor head comprises: a. a housing; b. a hollow cylindrical member detachably affixed to said housing open on both ends and containing said filament; c. means for providing a pressurized coupling between said filament and the interior wall of said hollow cylindrical member; d. means for mounting said first and second potentiometers within said housing; e. means for providing external adjustment of said first and second potentiometers; f. an electrical plug member mounted to said housing for providing a means for electrically decoupling said sensor head from the remainder of said pressure gauge; g. electrical coupling means for electrically coupling together said filament, said first and second potentiometers and said electrical plug member.
Claim 36
Dependent Claim
32 words
A pressure gauge as described in claim 14 wherein said means for providing a pressurized coupling between said filament and the interior wall of said hollow cylindrical member comprises an O-ring seal.
Claim 37
Dependent Claim
34 words
A pressure gauge as described in claim 13 wherein the maximum pressure indication of said indicator is adjustable by varying a first potentiometer coupled in series between said indicator and said second terminal point.
Claim 38
Dependent Claim
34 words
A pressure gauge as described in claim 13 wherein the minimum pressure indication of said indicator is adjustable by varying a second potentiometer coupled in series between said second terminal point and said filament.
Claim 39
Dependent Claim
28 words
A pressure gauge as described in claim 13 wherein said filament has coupled across it a resistor so as to expand the low pressure range of said gauge.
References Cited (Backward Citations)
US2938387A
Cited
US3066537A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |