# US 2009/0260772 A1 · Sheet Stabilization With Dual Opposing Cross Direction Air Clamps > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260772 A1 - Document ID: US20090260772A1 - Status: Published application - Kind: A1 - Application number: 12/106,247 - Filed: 2008-04-18 - Published: 2009-10-22 - Earliest claimed: 2008-04-18 - Assignees: Honeywell ASCa Inc. - Inventors: Tamer Mark Alev; Glen John Visser; Salvatore Chirico; Ron Beselt; Michael Kon Yew Hughes - Web page: https://patentgrep.com/patent/US20090260772A1 ## CPC - G01B 21/08: for measuring thickness - B65H 23/02: transversely (by tentering, gripper, or like apparatus operating on fabric webs D06C) - B65H 23/24: by fluid action, e.g. to retard the running web - D21F 7/06: Indicating or regulating the thickness of the layer; Signal devices - G01D 3/028: mitigating undesired influences, e.g. temperature, pressure - B65H 2406/112: for handling material along preferably rectilinear path, e.g. nozzle bed for web - B65H 2511/13: Thickness - B65H 2511/22: Distance - B65H 2801/84: Paper-making machines - G01B 2210/44: with detectors on both sides of the object to be measured - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES - D21F: PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR ## Abstract An air stabilization system employing two parallel, opposite facing Coanda nozzles, that are positioned adjacent a flexible moving web, with each nozzle exhausting gas at opposite directions, subjects the moving web to opposing forces effective to stabilize the web. Each nozzle includes an elongated slot that is parallel to the path of the moving web. The two Coanda nozzles serve as separate points along the machine direction for controlling the height of the moving web. By modulating the flow, pressure and other parameters of gases exiting the Coanda nozzles, the shape of the moving web between the nozzles can be manipulated to present a planar contour for measurements. The air stabilization system can be incorporated into a scanner head to measure the caliper of paper, plastic, and other flexible web products. ## Claims ### Claim 1 An air stabilization system for non-contact support of a flexible continuous web that is moving in a downstream machine direction (MD) that comprises: (a) a body having an operative surface facing the web wherein the operative face has a web entry end and a web exit end that is downstream from the web entry end; (b) a first nozzle, positioned on the operative surface, that defines a first slot that extends across the surface of the operative surface along the MD and wherein a first elongated jet of pressurized gas is exhausted through the first slot and moves toward a first downstream cross direction (CD) to impart a first controlled force on the web; and (c) a second nozzle, positioned on the operative surface, that defines a second slot that extends across the surface of the operative surface along the MD, wherein a second elongated jet of pressurized gas is simultaneously exhausted through the second slot and moves toward a second downstream CD to impart a second controlled force on the web, wherein the direction of the first downstream CD is opposite that of the second downstream CD and whereby the first force and the second force maintain at least a portion of the moving web, that is located between the web entry end and the web exit end, at a substantially fixed distance to the operative surface. ### Claim 2 (depends on 1) The system of claim 1 wherein the first nozzle comprises a slot in the body that is in fluid communication with a first source of gas and has a first elongated opening at a first surface of the body wherein the first slot has a first curved convex surface at the first elongated opening on its downstream side and wherein the second nozzle comprises a slot in the body that is in fluid communication with a second source of gas and has a second elongated opening at a second surface of the body wherein the second slot has a second curved convex surface at the second elongated opening on its downstream side. ### Claim 3 (depends on 2) The system of claim 2 wherein the distance between the first elongated opening to the second elongated opening ranges from about 3.3 to 10 cm. ### Claim 4 (depends on 1) The system of claim 1 comprising means for independently controlling the flow of the first elongated jet and the flow of the second elongated jet. ### Claim 5 (depends on 4) The system of claim 4 wherein the flow rate of the first elongated jet as it is exhausted from the first slot ranges from 2.5 to 7.0 cubic meters per hour and the flow rate of the second elongated jet as it is exhausted from the second slot ranges from 2.5 to 7.0 cubic meters per hour. ### Claim 6 (depends on 1) The system of claim 1 wherein the first slot has a length as measured along the CD that ranges from 2.9 to 8.6 cm and the second slot has a length as measured along the CD that ranges from 2.9 to 8.6 cm. ### Claim 7 (depends on 1) The system of claim 1 wherein the web comprises paper. ### Claim 8 A method of non-contact support of a flexible continuous web that is moving in a downstream machine direction (MD) along a path that comprises the steps of: (a) positioning an air stabilizer below the continuous web along the path wherein the stabilizer comprises: (i) a body having an operative surface facing the web wherein the operative face has a web entry end and a web exit end that is downstream from the web entry end; (ii) a first nozzle, positioned on the operative face, that defines a first slot that extends across the surface of the operative surface along a cross direction (CD), wherein the first nozzle is in fluid communication with a first source of gas; and (iii) a second nozzle, positioned on the operative face, that defines a second slot that extends across the surface of the operative surface along the CD wherein the second nozzle is in fluid communication with a second source of gas; (b) directing a first jet of gas from the first slot toward a first downstream cross direction (CD) to impart a first force on the continuous web; and (c) simultaneously directing a second jet of gas from the second slot toward a second downstream CD to impart a second force on the continuous web, wherein the direction of the first downstream CD is opposite that of the second stream CD, whereby the first force and the second force maintain at least a portion of the moving web, that is located between the web entry end and the web exit end, at a substantially fixed distance to the operative surface. ### Claim 9 (depends on 8) The method of claim 8 further comprising the step of independently regulating the first jet of gas and the second jet of gas to control the web's profile along the path over the operative surface. ### Claim 10 (depends on 9) The method of claim 9 comprising independently controlling the flow of the first elongated jet and the flow of the second elongated jet. ### Claim 11 (depends on 10) The method of claim 10 wherein the flow rate of the first elongated jet as it is exhausted from the first slot ranges from 2.5 to 7.0 cubic meters per hour and the flow rate of the second elongated jet as it is exhausted from the second slot ranges from 2.5 to 7.0 cubic meters per hour. ### Claim 12 (depends on 9) The method of claim 9 whereby the profile is manipulated in the MD, a CD or both MD and CD. ### Claim 13 (depends on 8) The method of claim 8 wherein the air stabilizer is scanned back and forth along the cross direction. ### Claim 14 A system for monitoring a flexible continuous web that is moving in a downstream machine direction (MD) that comprises: (a) an air stabilization system for non-contact support of the flexible continuous web, which has a first surface and a second surface, that comprises: (i) a body having an operative surface facing the web wherein the operative face has a web entry end and a web exit end that is downstream from the web entry end; (ii) a first nozzle, positioned on the operative face, that defines a first slot that extends across the surface of the operative surface along a MD and wherein a first elongated jet of pressurized gas is exhausted through the first slot and moves toward a first downstream CD to impart a first controlled force on the web; and (iii) a second nozzle, positioned on the operative face, that defines a second slot that extends across the surface of the operative surface along the MD, wherein a second elongated jet of pressurized gas is simultaneously exhausted through the second slot and moves toward a second downstream machine direction to impart a second controlled force on the web, wherein the direction of the first downstream CD is opposite to that of the second downstream CD and whereby the first force and the second force maintain at least a portion of the moving web, that is located between the web entry end and the web exit end, at a substantially fixed distance to the operative surface; (b) a first sensor head that is disposed adjacent the first surface of the web; and (c) means for regulating the first jet of gas and the second jet of gas to control the web's profile along the process path over the operative surface. ### Claim 15 (depends on 14) The system of claim 14 wherein the first sensor head is disposed within the body such that an active surface of the first sensor head is flushed with the operative surface and the system further comprises (d) a second sensor head that is disposed adjacent the second surface of the web. ### Claim 16 (depends on 15) The system of claim 15 wherein the first sensor includes means for measuring the distance between the first sensor and the first surface and the second sensor includes means for measuring the distance between the second sensor and the second surface and wherein the system further includes means for measuring the distance between the first sensor and the second sensor. ### Claim 17 (depends on 15) The system of claim 15 comprising means for scanning the first and second sensor heads back and forth along the cross direction. ### Claim 18 (depends on 15) The system of claim 15 wherein the distance between the first slot to the second slot ranges from about 3.3 to 10 cm. ### Claim 19 (depends on 15) The system of claim 15 comprising means for independently controlling the flow of the first elongated jet and the flow of the second elongated jet. ### Claim 20 (depends on 15) The system of claim 15 wherein the first and second sensor heads comprise means for measuring the thickness of the web.