# US 2009/0260771 A1 · Sheet Stabilizer With Dual Inline Machine Direction Air Clamps and Backsteps > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260771 A1 - Document ID: US20090260771A1 - Status: Published application - Kind: A1 - Application number: 12/105,274 - Filed: 2008-04-18 - Published: 2009-10-22 - Earliest claimed: 2008-04-18 - Assignees: Honeywell ASCa Inc. - Inventors: Tamer Mark Alev; Salvatore Chirico - Web page: https://patentgrep.com/patent/US20090260771A1 ## CPC - 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 - D21G 9/0036: {controlling the press or drying section} - D21G 9/0063: {Devices for threading a web tail through a paper-making machine} - B65H 2406/112: for handling material along preferably rectilinear path, e.g. nozzle bed for web - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES - D21F: PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON - D21G: CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES (winders or rewinders for finished products, means for adjustment of wrinkles or lateral extensions B65H) ## Abstract An air stabilization system employing two substantially parallel, codirectional Coanda nozzles, that are positioned adjacent a flexible moving web, with each nozzle exhausting gas at the same downstream machine direction, subjects the moving web to shear forces effective to stabilize the web. Each nozzle includes an elongated slot that is substantially perpendicular to the path of the moving web and a backstep located downstream of the direction of airflow extending from the Coanda slot. The two Coanda nozzles serve as separate points along the machine direction for controlling the height of the moving web. By modulating the velocities or 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 surface has a web entry end and a web exit end that is downstream from the web entry end; (b) a first nozzle, positioned at the web entry end, that defines a first slot that extends across the surface of the operative surface along a first direction that is substantially transverse to the MD and wherein a first elongated jet of pressurized gas is exhausted through the first slot and moves toward a downstream MD to impart a first controlled force on the web; and (c) a second nozzle, positioned at the web exit end, that defines a second slot that extends across the surface of the operative surface along a second direction that is substantially transverse to the MD, wherein a second elongated jet of pressurized gas is simultaneously exhausted through the second slot and moves toward a downstream MD to impart a second controlled force on the web 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 first elongated opening is disposed on a first segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion and the second elongated opening is disposed on a second segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion. ### Claim 4 (depends on 3) The system of claim 3 wherein the first upper portion is vertically spaced from the first lower portion and the second upper portion is vertically spaced from the second lower portion. ### Claim 5 (depends on 4) The system of claim 4 wherein the first upper portion and the first lower portion are substantially parallel to each other and the surface connecting the first upper portion to the first lower portion defines a first plane that is substantially perpendicular to the first upper portion and the first lower portion and wherein the second upper portion and the second lower portion are substantially parallel to each other and the surface connecting the second upper portion to the second lower portion defines a second plane that is substantially perpendicular to the second upper portion and the second lower portion ### Claim 6 (depends on 4) The system of claim 4 wherein the vertical distance between the first upper portion and the first lower portion is about 2 to 7 mm and the vertical distance between the second upper portion and the second lower portion is about 2 to 7 mm. ### Claim 7 (depends on 1) The system of claim 1 wherein the distance between the first elongated opening to the second elongated opening ranges from 1.7 to 5 cm. ### Claim 8 (depends on 1) The system of claim 1 comprising means for controlling the pressure of the first elongated jet and the pressure of the second elongated jet. ### Claim 9 (depends on 8) The system of claim 8 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 10 (depends on 1) The system of claim 1 wherein the first slot has a length as measured along a cross direction that is transverse to MD that ranges from 4 to 11 cm and the second slot has a length as measured along a cross direction that is transverse to MD that ranges from 4 to 11 cm. ### Claim 11 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 surface has a web entry end and a web exit end that is downstream from the web entry end; (ii) a first nozzle, positioned at the web entry end, that defines a first slot that extends across the surface of the operative surface along a first direction that is substantially transverse to the MD, wherein the first nozzle is fluid communication with a first source of gas; and (iii) a second nozzle, positioned at the web exit end, that defines a second slot that extends across the surface of the operative surface along a second direction that is substantially transverse to the MD wherein the second nozzle is fluid communication with a second source of gas; (b) directing a first jet of gas from the first slot toward a downstream MD to impart a first force on the continuous web; and (c) simultaneously directing a second jet of gas from the second slot toward a downstream MD to impart a second force on the continuous web, 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 12 (depends on 11) The method of claim 11 further comprising the step of 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 13 (depends on 12) The method of claim 12 whereby the profile is manipulated in the MD. ### Claim 14 (depends on 11) The method of claim 11 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 15 (depends on 14) The method of claim 14 wherein first elongated opening is disposed on a first segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion and the second elongated opening is disposed on a second segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion. ### Claim 16 A system for monitoring a 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 surface 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 at the web entry end, that defines a first slot that extends across the surface of the operative surface along a first direction that is substantially transverse to the MD and wherein a first elongated jet of pressurized gas is exhausted through the first slot and moves toward a downstream MD to impart a first controlled force on the web; and (iii) a second nozzle, positioned on the operative face at the web exit end, that defines a second slot that extends across the surface of the operative surface along a second direction that is substantially transverse to the MD, wherein a second elongated jet of pressurized gas is simultaneously exhausted through the second slot and moves toward a downstream machine direction to impart a second controlled force on the web 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 17 (depends on 16) The system of claim 16 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 comprising (d) a second sensor head that is disposed adjacent the second surface of the web. ### Claim 18 (depends on 17) The system of claim 17 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 19 (depends on 16) The system of claim 16 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 20 (depends on 19) The system of claim 19 wherein first elongated opening is disposed on a first segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion and the second elongated opening is disposed on a second segment of the operative surface which has a first upper portion and a first lower portion that is downstream from the first upper portion.