US3769835A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pitot calibrated air velocity measuring system with transducer
Assignee: Alnor Instrument Co
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Filing: 1970-10-06
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Granted: 1973-11-06
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Expires: 1990-10-06
Abstract
Abstract An air velocity measuring system having a probe adapted to be placed into a flow of air and coupled to a measuring apparatus. The measuring apparatus may be a flow meter having a moving vane which is responsive to the air passing through the probe or it may be an electrical transducer adapted to be responsive to a flow of air through the probe. In the preferred embodiment of the invention a range adjusting switch is coupled between the probe and the measuring apparatus and enables the system to have a plurality of ranges by placing a resistance, in the form of one of a plurality of needle valves, into the path of the air flow to the measuring apparatus. The probe is a conduit having means for adjusting the quantity of air flowing to the measuring apparatus. In the preferred embodiment, the probe, the range adjusting switch, and the measuring apparatus are calibrated as a system. Once calibrated, the individual elements of the system are interchangeable with the corresponding elements of another of similarly calibrated mass produced systems without requiring subsequent recalibration of each system. The means for adjusting the quantity of air flowing to the measuring device are adjustable during the calibration of the probes individually or as part of the air velocity measuring system.
Inventors
- 👤 A Obermaier
- 👤 M Pierman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:26
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/68; G01F1/684; G01F1/05; G01F1/34; G01F1/36; G01F1/40; G01F1/46; G01F25/00; G01F25/10; G01P; G01P21/00; G01P21/02; G01P21/025; G01P5/00; G01P5/10; G01P5/14; G01P5/16
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
234 words
The combination of an air velocity measuring transducer and an air velocity probe, said transducer comprising: a housing having an input, an output and a tubular extension; said tubular extension defining a pair of passageways which communicate, respectively, with said input and said output, separately; a thermo-element positioned between said input and said output within said housing so that air flow passing through one of said passageways influences said thermo-element to generate thermoresponsive changes; and electrical coupling means coupled to said thermo-element for enabling energization thereof and also coupled for transmitting from said housing said thermo-responsive changes; said air velocity probe comprising: a conduit one end of which is constructed to be connected to said tubular extension and the other end of which is constructed for being positioned transverse to an air stream, the velocity of which is to be measured; said conduit defining a pair of tubes for connection, respectively, to said pair of passageways; connection of said probe to said transducer defining a continuous air flow path into and through one of said tubes, through one of said passageways, through said housing, through the other of said passageways, and through and then outward from the other of said tubes; and means for controlling the amount of air flow passing through said transducer, said controlling means comprising a needle valve which defines a channel communicating with said thermo-element and one of said passageways.
Claim 2
Dependent Claim
234 words
The combination of an air velocity measuring transducer and an air velocity probe, said transducer comprising: a housing having an input, an output and a tubular extension; said tubular extension defining a pair of passageways which communicate, respectively, with said input and said output, separately; a thermo-element positioned between said input and said output within said housing so that air flow passing through one of said passageways influences said thermo-element to generate thermoresponsive changes; and electrical coupling means coupled to said thermo-element for enabling energization thereof and also coupled for transmitting from said housing said thermo-responsive changes; said air velocity probe comprising: a conduit one end of which is constructed to be connected to said tubular extension and the other end of which is constructed for being positioned transverse to an air stream, the velocity of which is to be measured; said conduit defining a pair of tubes for connection, respectively, to said pair of passageways; connection of said probe to said transducer defining a continuous air flow path into and through one of said tubes, through one of said passageways, through said housing, through the other of said passageways, and through and then outward from the other of said tubes; and means for controlling the amount of air flow passing through said transducer, said controlling means comprising a needle valve which defines a channel communicating with said thermo-element and one of said passageways.
Claim 3
Dependent Claim
40 words
The combination as define in claim 1 wherein said tubes each has a D-shaped cross section and said tubes are positioned within said conduit so tha the arcuate surface of said D-shaped tubes abuts the interior surface of said conduit.
Claim 4
Dependent Claim
245 words
The combination of an air velocity measuring transducer and an air velocity probe, said transducer comprising: a housing having an input, an output and a tubular extension; said tubular extension defining a pair of passageways which communicate, respectively, with said input and said output, separately: a thermo-element positioned between said input and said output within said housing so that air flow passing through one of said passageways influences said thermo-element to generate thermo-responsive changes; and electrical coupling means coupled to said thermo-element for enabling energization thereof and also coupled for transmitting from said housing said thermo-responsive changes; said air velocity probe comprising: a conduit one end of which is constructed to be connected to said tubular extension and the other end of which is constructed for being positioned transverse to an air stream, the velocity of which is to be measured; said conduit defining a pair of tubes for connection, respectively, to said pair of passageways; connection of said probe to said transducer defining a continuous air flow path into and through one of said tubes, through one of said passageways, through said housing, through the other of said passageways, and through and then outward from the other of said tubes; said probe further comprising an air flow control member affixed to the other end of said conduit, a passageway through said member transverse to said pair of conduit tubes, and a variable baffle disposed within said air flow member and transverse to said passageway.
Claim 5
Dependent Claim
245 words
The combination of an air velocity measuring transducer and an air velocity probe, said transducer comprising: a housing having an input, an output and a tubular extension; said tubular extension defining a pair of passageways which communicate, respectively, with said input and said output, separately: a thermo-element positioned between said input and said output within said housing so that air flow passing through one of said passageways influences said thermo-element to generate thermo-responsive changes; and electrical coupling means coupled to said thermo-element for enabling energization thereof and also coupled for transmitting from said housing said thermo-responsive changes; said air velocity probe comprising: a conduit one end of which is constructed to be connected to said tubular extension and the other end of which is constructed for being positioned transverse to an air stream, the velocity of which is to be measured; said conduit defining a pair of tubes for connection, respectively, to said pair of passageways; connection of said probe to said transducer defining a continuous air flow path into and through one of said tubes, through one of said passageways, through said housing, through the other of said passageways, and through and then outward from the other of said tubes; said probe further comprising an air flow control member affixed to the other end of said conduit, a passageway through said member transverse to said pair of conduit tubes, and a variable baffle disposed within said air flow member and transverse to said passageway.
Claim 6
Dependent Claim
63 words
The combination as defined in claim 3 wherein said air flow control member further includes: a fixed baffle disposed within and transverse to said passageway opposite said variable baffle, said variable baffle and said fixed baffle being disposed so that part of the air flow passing into said passageway is diverted into said one tube communicating with the input to said measuring device.
Claim 7
Dependent Claim
43 words
The combination as defined in claim 3 wherein said variable baffle comprises: a threaded bore coaxial with said conduit and communicating with said passageway through said member, and a threaded needle valve coacting with said threaded bore and partially extending into said passageway.
Claim 8
Dependent Claim
167 words
An air velocity measuring system comprising: a conduit adapted to be placed into a flow of air, the velocity of which is to be measured, said conduit having precalibrated air flow control means positioned therein, an air velocity measuring device having an air flow input and output, and a measuring device range adjusting switch coupled between said conduit and said measuring device and defining an air path thereto, said switch having selectible air resistance means for placement into said air path; said air velocity measuring device being a transducer comprising: a housing having a tubular extension constructed therebetween, a first and a second passageway defined within said tubular extension, said passageways separately communicating with said input and output, respectively, of said air velocity measuring device, means for controlling the amount of air flow passing through said transducer, and a thermo-element disposed between said input and said output, for sensing changes of air velocity of the air flow passing thereover and transducing such changes into a calibrated output.
Claim 9
Dependent Claim
167 words
An air velocity measuring system comprising: a conduit adapted to be placed into a flow of air, the velocity of which is to be measured, said conduit having precalibrated air flow control means positioned therein, an air velocity measuring device having an air flow input and output, and a measuring device range adjusting switch coupled between said conduit and said measuring device and defining an air path thereto, said switch having selectible air resistance means for placement into said air path; said air velocity measuring device being a transducer comprising: a housing having a tubular extension constructed therebetween, a first and a second passageway defined within said tubular extension, said passageways separately communicating with said input and output, respectively, of said air velocity measuring device, means for controlling the amount of air flow passing through said transducer, and a thermo-element disposed between said input and said output, for sensing changes of air velocity of the air flow passing thereover and transducing such changes into a calibrated output.
Claim 10
Dependent Claim
39 words
An air velocity measuring system as defined in claim 6 wherein said means for controlling the amount of air flow through said transducer comprises: a needle valve which defines a channel communicating with said thermo-element and said second passageway.
Claim 11
Dependent Claim
55 words
An air velocity measuring system as defined in claim 6 wherein said air flow control means comprises: an air flow control member affixed to one end of said conduit and having a passageway transverse to said conduit, and a variable baffle disposed within said air flow control member and transverse to said control member passageway.
Claim 12
Dependent Claim
33 words
An air velocity measuring system as defined in claim 8 wherein said air flow control member further comprises: a fixed baffle disposed within and transverse to said control member passageway opposite siad baffle.
Claim 13
Dependent Claim
73 words
An air velocity measuring system as defined in claim 9 wherein said variable baffle comprises: a threaded bore coaxial with said conduit and communicating with said control member passageway through said member, and a threaded valve coacting with said threaded bore and capable of partially extending into said control member passageway, whereby said air flow control member channels a portion of the air flow passing into said control member passageway into said conduit.
Claim 14
Dependent Claim
113 words
An air velocity measuring system as defined in claim 6 wherein said conduit includes a pair of adjacent tubes for communication to and from said range adjusting switch, and said range adjusting switch comprises: a pair of longitudinally positioned chambers, a receptacle at one end of said pair of chAmbers, said receptacle being adapted for connecting said tubes to said chambers, said selectible air resistance means consists of a plurality of restrictve members, and means for placing a selected one of said plurality of restrictive members into one of said chambers to restrict the air flow through said measuring device, said chambers being coupled to the input and output of said measuring device.
Claim 15
Dependent Claim
81 words
An air velocity measuring system as defined in claim 11 wherein said first and second passageways of said transducer housing are adapted to communicate with said pair of chambers, a filter is positioned adjacent said input so that an air flow passing through said first passageway enters said filter, said thermo-element is disposed between said filter and said output, and electrical coupling means are provided for enabling energization of said thermo-element and for transmitting the calibrated output thereof from said housing.
Claim 16
Dependent Claim
114 words
An air velocity measuring system as defined in claim 11 wherein said conduit has a first and a second end and includes a pair of adjacent tubes, one end of one of said conduit tubes is closed to inhibit the flow of air therethrough, said conduit and said one tube is apertured proximate said first end of said conduit so as to define means whereby air flow passes from said one tube to the input of said measuring device, both said tubes are adapted to be coupled to said range adjusting switch proximate the first end of said conduit, and said air flow control means is affixed to the second end of said conduit.
Claim 17
Dependent Claim
44 words
An air velocity measuring system as defined in claim 13 wherein each of said tubes has a D-shaped cross section and is positioned within said conduit so that the interior surface of said conduit is abutted by the arcuate surface of said D-shaped tubes.
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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) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |