US3895531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for sensing volumetric rate of air flow
Assignee: Individual
•
Filing: 1969-03-17
•
Granted: 1975-07-22
•
Expires: 1989-03-17
Abstract
Abstract An apparatus for sensing volumetric rate of air flow for use in heating and cooling systems for measuring the ram or velocity air pressure over a substantial transverse area of a duct by sensing the total and static air pressure within the duct through hollow plenum-like members disposed within the duct, each of the members having openings, one of which has openings facing the general air flow direction and the other of which has openings perpendicular to the general direction of air flow.
Inventors
- 👤 Robert R Lambert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:42
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/36; G01F1/40; G01F1/46
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
146 words
An apparatus for sensing volumetric rate of air flow comprising: a total pressure sensing hollow tubular member having a series of axially spaced in-line openings facing the general direction of air flow, a static air flow pressure sensing hollow tubular member having at least one series of axially spaced in-line openings facing normal to the direction of air flow, means for supporting said total pressure sensing member and said static pressure sensing member in a plane transverse to the general direction of air flow and spaced from each other to form a nozzle therebetween, said openings in said static air flow pressure sensing hollow tubular member facing said total pressure sensing hollow tubular member to open towards said nozzle, and means for measuring differential pressure in fluid communication with the total and static pressure sensing members so as to provide an indication of the velocity pressure.
Claim 2
Independent Claim
146 words
An apparatus for sensing volumetric rate of air flow comprising: a total pressure sensing hollow tubular member having a series of axially spaced in-line openings facing the general direction of air flow, a static air flow pressure sensing hollow tubular member having at least one series of axially spaced in-line openings facing normal to the direction of air flow, means for supporting said total pressure sensing member and said static pressure sensing member in a plane transverse to the general direction of air flow and spaced from each other to form a nozzle therebetween, said openings in said static air flow pressure sensing hollow tubular member facing said total pressure sensing hollow tubular member to open towards said nozzle, and means for measuring differential pressure in fluid communication with the total and static pressure sensing members so as to provide an indication of the velocity pressure.
Claim 3
Dependent Claim
43 words
The apparatus for sensing volumetric rate of air flow as in claim 1 wherein the distance between said total and static pressure sensing members is approximately equal to one-half of the diameter of one of said total and static pressure sensing tubular members.
Claim 4
Independent Claim
173 words
An apparatus for sensing the differeNtial between an average total pressure and an average static pressure across a duct through which a fluid is flowing for use with a differential pressure responsive means, said apparatus comprising: a pair of hollow tubular members, each having a series of axially spaced in-line openings through a sidewall thereof, said members each having means for connecting them to said differential pressure responsive means; and means for mounting said members in spaced apart relation in a plane normal to the flow of fluid in said duct with the openings of one of said members facing into the flow of fluid for sensing total pressure across said duct and the openings of the other of said members facing normal to the flow of fluid and generally toward said one of said members to sense a reduced static pressure in said duct between said members produced due to an acceleration of fluid flow between said members due to their presence in said duct to thereby produce an increased differential pressure.
Claim 5
Independent Claim
173 words
An apparatus for sensing the differeNtial between an average total pressure and an average static pressure across a duct through which a fluid is flowing for use with a differential pressure responsive means, said apparatus comprising: a pair of hollow tubular members, each having a series of axially spaced in-line openings through a sidewall thereof, said members each having means for connecting them to said differential pressure responsive means; and means for mounting said members in spaced apart relation in a plane normal to the flow of fluid in said duct with the openings of one of said members facing into the flow of fluid for sensing total pressure across said duct and the openings of the other of said members facing normal to the flow of fluid and generally toward said one of said members to sense a reduced static pressure in said duct between said members produced due to an acceleration of fluid flow between said members due to their presence in said duct to thereby produce an increased differential pressure.
Claim 6
Independent Claim
131 words
An apparatus for sensing average total and static pressures across a duct through which a fluid is flowing for a comparison thereof, said apparatus comprising: a first hollow tubular means having a first series of axially spaced in-line openings through a sidewall thereof and means for mounting it across said duct with said openings facing into the flow of fluid therein for sensing an average of total fluid pressure across said duct; a second hollow tubular means having a second series of axially spaced in-line openings through a sidewall thereof and means for mounting it across said duct in spaced relation to said first hollow tubular means for accelerating fluid flow therebetween with said second series of openings facing normal to said flow of fluid and toward said first tubular means.
Claim 7
Independent Claim
131 words
An apparatus for sensing average total and static pressures across a duct through which a fluid is flowing for a comparison thereof, said apparatus comprising: a first hollow tubular means having a first series of axially spaced in-line openings through a sidewall thereof and means for mounting it across said duct with said openings facing into the flow of fluid therein for sensing an average of total fluid pressure across said duct; a second hollow tubular means having a second series of axially spaced in-line openings through a sidewall thereof and means for mounting it across said duct in spaced relation to said first hollow tubular means for accelerating fluid flow therebetween with said second series of openings facing normal to said flow of fluid and toward said first tubular means.
Claim 8
Independent Claim
118 words
A method of producing a pressure differential which is greater than, but linearly related to, the actual differential between the average total fluid pressure and the average static pressure across a duct in which a fluid is flowing comprising the steps of: sensing an average of total pressure across said duct in a first transverse portion thereof; accelerating the flow of fluid in at least one other transverse portion of said duct; sensing an average of static pressure of fluid flow in said other transverse portion of said duct; and comparing said average pressures to obtain a pressure differential which is different from, but linearly related to, the actual velocity pressure of said fluid flowing in said duct.
Claim 9
Independent Claim
118 words
A method of producing a pressure differential which is greater than, but linearly related to, the actual differential between the average total fluid pressure and the average static pressure across a duct in which a fluid is flowing comprising the steps of: sensing an average of total pressure across said duct in a first transverse portion thereof; accelerating the flow of fluid in at least one other transverse portion of said duct; sensing an average of static pressure of fluid flow in said other transverse portion of said duct; and comparing said average pressures to obtain a pressure differential which is different from, but linearly related to, the actual velocity pressure of said fluid flowing in said duct.
Claim 10
Dependent Claim
181 words
The method of producing a pressure differential as in claim 5 wherein: said step of sensing an average of total pressure across a first transverse portion of said duct includes the step of locating a hollow tubular member with a plurality of axially spaced in-line openings therein, across said duct, with the openings facing into the flow of fluid into said duct; said step of accelerating the flow of fluid in at least one other transverse portion of said duct includes the step of placing a second hollow tubular member having a plurality of axially spaced in-line openings, in said duct in spaced relation to said first member to place said members in a plane transverse to the flow of fluid in said duct with the flow of fluid between said members being accelerated due to the presence of said members; and said step of sensing an average of static pressure includes the step of locating the axially spaced in-line opening in said second hollow tubular member to face toward said first tubular member and the fluid flowing between said members.
References Cited (Backward Citations)
US886255A
Cited
US1087930A
Cited
US1116938A
Cited
US1145222A
Cited
US1250238A
Cited
US1508017A
Cited
US2325018A
Cited
US2609183A
Cited
US2828076A
Cited
US3422682A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |