US3818327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Measuring gauge with support for holding measured sheet and discharging foreign matter
Assignee: Industrial Nucleonics Corp
•
Filing: 1972-09-05
•
Granted: 1974-06-18
•
Expires: 1992-09-05
Abstract
Abstract A gauge is provided for measuring a particular property of a moving sheet or web of material. In a preferred embodiment, an air caliper gauge for measuring the thickness of sheet material comprises a sensing element floating on an air film at a constant distance above the sheet and a sheet support below and in contact with the sheet. The sensing element and the sheet support form part of a transducer circuit providing an indication of the sheet thickness. Suction, which is applied to the sheet through apertures in a surface of the sheet support to maintain the sheet in a stable condition while it is measured, is produced by pressure-reducing structure within the sheet support responsive to a source of compressed air and functioning as a Venturi system. Foreign matter entering the pressure-reducing structure through the apertures in the support surface is ejected. Accordingly, the accumulation of such matter is suppressed, the efficiency of the pressure-reducing structure in providing suction to the sheet is kept unimpaired, and the accuracy of the gauging system is maintained.
Inventors
- 👤 A Alexander
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:02
CPC Classifications
G; G01; G01B; G01B13/00; G01B13/02; G01B13/06; G01B2210/00; G01B2210/40; G01B2210/42; G01B2210/62
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
134 words
Apparatus for measuring a property of a traveling material sheet, comprising means having a surface to be maintained in contact with a portion of said sheet and a gas-confining chamber that communicates gas to said surface and foreign matter from sAid surface to said gas-confining chamber, a positive pressure source of fluid coupled to said chamber, gas pressure-reducing means within said chamber responsive to said fluid pressure source for providing suction at said surface to maintain said sheet portion in close contact with said surface, said gas pressure-reducing means including a venting orifice through which foreign matter entering said gas-confining chamber from said fluid pressure source and through said surface may be substantially discharged, and sensing means responsive to said sheet held in contact with said surface for providing an indication of said property.
Claim 2
Dependent Claim
134 words
Apparatus for measuring a property of a traveling material sheet, comprising means having a surface to be maintained in contact with a portion of said sheet and a gas-confining chamber that communicates gas to said surface and foreign matter from sAid surface to said gas-confining chamber, a positive pressure source of fluid coupled to said chamber, gas pressure-reducing means within said chamber responsive to said fluid pressure source for providing suction at said surface to maintain said sheet portion in close contact with said surface, said gas pressure-reducing means including a venting orifice through which foreign matter entering said gas-confining chamber from said fluid pressure source and through said surface may be substantially discharged, and sensing means responsive to said sheet held in contact with said surface for providing an indication of said property.
Claim 3
Dependent Claim
41 words
Apparatus as in claim 1, wherein said gas pressure-reducing means comprises means responsive to said fluid pressure source for expanding said fluid, whereby the gas pressure inside said chamber communicating to said surface is reduced relative to that outside said chamber.
Claim 4
Dependent Claim
54 words
Apparatus as in claim 2, wherein said gas pressure-reducing means comprises means responsive to said fluid pressure source for alternatively expanding and compressing said fluid, the overall amount of expansion exceeding the amount of compression, whereby the gas pressure inside said chamber communicating to said surface is reduced relative to that outside said chamber.
Claim 5
Dependent Claim
102 words
Apparatus as in claim 3, wherein said fluid pressure source has a fluid outlet in said chamber and said gas pressure-reducing means comprises structure in the form of a hollow truncated cone having a large opening at one end and a small opening at the other end, the large opening of said structure receiving fluid from said fluid outlet, the small opening of said structure communicating with said venting orifice, whereby the pressure of said fluid entering said structure is reduced thereby effecting a reduction in the gas pressure inside said chamber communicating to said surface relative to that outside said chamber.
Claim 6
Dependent Claim
88 words
Apparatus as in claim 4, wherein said gas pressure-reducing means comprises additional structure in the form of one or more additional hollow truncated cones, said hollow truncated cones being of graduated sizes and arranged substantially coaxially, the small opening of each additional hollow truncated cone communicating with the large opening of a successive hollow truncated cone in the direction of fluid flow, the sizes of said hollow truncated cones increasing in the direction of fluid flow, whereby the gas pressure inside said chamber is reduced in several stages.
Claim 7
Dependent Claim
16 words
Apparatus as in claim 4, wherein the inner surface of said hollow truncated cone is complex.
Claim 8
Dependent Claim
16 words
Apparatus as in claim 5, wherein the inner surface of said hollow truncated cones are convex.
Claim 9
Dependent Claim
90 words
Apparatus as in claim 1 for measuring the thickness of said sheet, comprising support means having said surface on a face thereof, means for locating said sensing means and said support means on opposite sides of the said sheet, and means providing a gas film interposed between said sensing means and said sheet whereby said sensing means is maintained at said constant distance from said sheet to provide an indication of the thickness of said sheet which is proportional to the distance between said sensing means and said support means.
Claim 10
Dependent Claim
54 words
Apparatus as in claim 8, wherein said gas pressure-reducing means comprises means responsive to said fluid pressure source for alternatively expanding and compressing said fluid, the overall amount of expansion exceeding the amount of compression, whereby the gas pressure inside said chamber communicating to said surface is reduced relative to that outside said chamber.
Claim 11
Dependent Claim
102 words
Apparatus as in claim 9, wherein said fluid pressure source has a fluid outlet in said chamber and said gas pressure-reducing means comprises structure in the form of a hollow truncated cone having a large opening at one end and a small opening at the other end, the large opening of said structure receiving fluid from said fluid outlet, the small opening of said structure communicating with sAid venting orifice, whereby the pressure of said fluid entering said structure is reduced thereby effecting a reduction in the gas pressure inside said chamber communicating to said surface relative to that outside said chamber.
Claim 12
Dependent Claim
88 words
Apparatus as in claim 10, wherein the gas pressure-reducing means comprises additional structure in the form of one or more additional hollow truncated cones, said hollow truncated cones being of graduated sizes and arranged substantially coaxially, the small opening of each additional hollow truncated cone communicating with the large opening of a successive hollow truncated cone in the direction of fluid flow, the sizes of said hollow truncated cones increasing in the direction of fluid flow, whereby the gas pressure inside said chamber is reduced in several stages.
Claim 13
Dependent Claim
16 words
Apparatus as in claim 10, wherein the inner surface of said hollow truncated cone is convex.
Claim 14
Dependent Claim
16 words
Apparatus as in claim 11, wherein the inner surface of said hollow truncated cones are convex.
Claim 15
Dependent Claim
102 words
Apparatus of claim 1, wherein said fluid pressure source has a fluid outlet in said chamber and said gas pressure-reducing means comprises structure in the form of a hollow truncated cone having a large opening at one end and a small opening at the other end, the large opening of said structure receiving fluid expanding from said fluid outlet, the small opening of said structure communicating with said venting orifice, whereby the pressure of said fluid entering said structure is reduced thereby effecting a reduction in the gas pressure inside said chamber communicating to said surface relative to that outside said chamber.
Claim 16
Dependent Claim
87 words
Apparatus of claim 14, wherein said gas pressure-reducing means comprises additional structure in the form of one or more additional hollow truncated cones, said hollow truncated cones being of graduated sizes and arranged substantially coaxially, the small opening of each additional hollow truncated cone communicating with the large opening of a successive hollow truncated cone in the direction of fluid flow, the sizes of said hollow truncated cones increasing in the direction of fluid flow, whereby the gas pressure inside said chamber is reduced in several stages.
References Cited (Backward Citations)
US3617872A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |