# US 2013/0153076 A1 · Durable semi-rigid single-layer flexible duct > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153076 A1 - Document ID: US20130153076A1 - Status: Published application - Kind: A1 - Application number: 13/740,204 - Filed: 2013-01-13 - Published: 2013-06-20 - Earliest claimed: 2010-01-24 - Inventors: Steven Allan Liebson; Graeme Anthony Liebson; Robert Cohen - Web page: https://patentgrep.com/patent/US20130153076A1 ## CPC - F16L 11/24: wound from strips or bands (F16L11/16 takes precedence) - B21C 37/154: {Making multi-wall tubes} - D06F 58/20: General details of domestic laundry dryers (D06F59/00 takes precedence) - F16L 11/081: {comprising one or more layers of a helically wound cord or wire (in combination with braided layers F16L11/088)} - F16L 11/112: having reinforcements embedded in the wall - F24F 13/0218: {Flexible soft ducts, e.g. ducts made of permeable textiles} - Y10T 29/49908: Joining by deforming - Y10T 428/1393: Multilayer [continuous layer] - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL - B21C: MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES, PROFILES OR LIKE SEMI-MANUFACTURED PRODUCTS OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL - D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A durable, semi-rigid, single-layered flexible duct having a sleeve made of a single aluminum layer and a resilient wound element disposed at the mid-point of the overlap region of the aluminum layer. The wound element imparts corrugations to the sleeve, such that the duct is extendible between a compacted configuration suitable for storage and for shipping and an extended configuration suitable for installation in a gas transport arrangement. Closely and evenly-spaced ridges that are situated in between the corrugations, add rigidity and durability to the duct. The inward-facing surface of the aluminum ribbon is substantially smooth and featureless except for the helical corrugations imparted by wire winding and the closely and evenly-spaced ridges. The aluminum sleeve is of a predetermined thickness rendering the duct substantially rigid when in an extended configuration and enabling the duct to maintain its substantial rigidity upon extension from a compacted configuration. ## Claims ### Claim 1 A durable semi-rigid, flexible duct having an axis running the length of said duct, comprising: a single aluminum ribbon; a resilient wound element, wherein said wound element is disposed at the mid point of the overlap region of said aluminum ribbon; wherein said wound element imparts corrugations to said aluminum ribbon, said aluminum ribbon being formed with a plurality of closely and evenly-spaced ridges embossed in between a pair of said corrugations, such that said duct is axially extendible between a compacted configuration suitable for storage and for shipping and an extended configuration suitable for installation in an air transport arrangement; wherein said aluminum ribbon is of a predetermined thickness rendering said duct substantially rigid when in said extended configuration and enabling said duct to maintain its substantial rigidity upon extension from said compacted configuration; and wherein said closely and evenly-spaced ridges impart additional rigidity to said duct, causing said duct to be resilient and withstand heavy impact forces, which might crush the duct and reduce its diameter. ### Claim 2 (depends on 1) The duct of claim 1, wherein said duct is in said extended configuration after having been compressed to said compacted configuration, wherein the relative length between them, is in a ratio which may vary in a range between 1:2.5 to 1:5, between said compacted configuration and said extended configuration, and said aluminum ribbon having an inward-facing surface being substantially smooth and featureless except for said wound corrugations and said closely and evenly-spaced ridges. ### Claim 3 (depends on 1) The duct of claim 1, wherein said aluminum foil ribbon layer is of a thickness in a range of 80 to 100 microns. ### Claim 4 (depends on 1) The duct of claim 1, wherein said duct has a cross-sectional configuration selected from the group which consists of: a circular configuration, a polygonal configuration and a compound configuration wherein said duct is partially circular and partially polygonal. ### Claim 5 (depends on 1) The duct of claim 1, wherein, when a predetermined length L of said duct, of diameter d, is in the extended configuration and is disposed horizontally and supported at a first end thereof, said duct is operative to bend under the influence of gravitational force such that a second unsupported end thereof is lower than said first supported end by no more than y, such that (y/L)×100≦p, wherein p is a predetermined percentage of L. ### Claim 6 (depends on 1) The duct of claim 1, wherein, when a predetermined length L of said duct, of diameter d, is in the extended configuration and is disposed horizontally and supported at both ends thereof, said duct is operative to bend under the influence of gravitational force such that the central portion thereof is lower than the level of said supported ends by no more than c, such that (c/L)×100≦q, wherein q is a predetermined percentage of L. ### Claim 7 (depends on 3) The duct of claim 3, wherein, when L=2 meters and d=10 centimeters, c≦0.001M, and wherein, when said duct is in said extended configuration upon extension from said compacted configuration, c≦0.003M. ### Claim 8 (depends on 1) The duct of claim 1, wherein said resilient wound element is fabricated of a metal having spring-like resilience. ### Claim 9 (depends on 8) The duct of claim 8, wherein said resilient wound element is a wound galvanized wire having a diameter in the range of 0.9 to 1.3 millimeters. ### Claim 10 (depends on 1) The duct of claim 1, wherein said duct is selected from the group which consists of: a gas transport duct; and a duct for enclosing utility supply lines. ### Claim 11 (depends on 1) The duct of claim 1, wherein said duct has a cross-sectional configuration selected from a group which consists of: circular, polygonal, square; and rectangular configuration. ### Claim 12 (depends on 1) The duct of claim 1, wherein said closely and evenly-spaced ridges of said duct serve as threads that enable a screw-type connection. ### Claim 13 (depends on 12) The duct of claim 12, wherein said screw-type connection is provided by a duct connector ring comprising tooth-like projections matching said closely and evenly-spaced ridges of said duct, said projections provided on one side thereof, the other side thereof comprising means for connection to additional accessories. ### Claim 14 (depends on 13) The duct of claim 13, wherein said means for connection comprises an annular ridge, for connection to an adaptor ring formed with an annular groove on one side thereof, said groove matching said annular ridge of said duct connector ring, so that when said adaptor ring and said duct connector ring are brought together they connect via a snap-on connection between said annular ridge and said annular groove, and wherein the other side of said adaptor ring is the appliance connection side for connecting to at least one of a dryer and pipe. ### Claim 15 (depends on 13) The duct of claim 13, wherein said duct connector ring is connected to a lint trap, for the purpose of collecting lint that is released from said duct, so as not to allow said lint to scatter around the vicinity of the dryer, said lint trap comprising a top part having an integrally formed said adaptor ring, including said annular groove for connecting to said connector ring. ### Claim 16 (depends on 15) The duct of claim 15, wherein said duct connector ring is connected to a draft blocker which is utilized for the exhaust on the end of said duct, connecting it through a wall, said draft blocker comprising, an inlet section functioning as said adaptor ring for connecting to said connector ring threaded onto said duct. ### Claim 17 A method for manufacturing a semi-rigid, flexible duct, comprising the steps of: a) providing a mandrel of preselected diameter for fabricating a duct therearound; b) providing a continuous aluminum ribbon of predetermined thickness; c) wrapping said continuous ribbon with a predetermined overlap around said mandrel to form a sleeve, wherein said sleeve is formed by the overlap of said ribbon upon itself; d) applying glue to said continuous ribbon for the bonding of said overlap, wherein said glue is cured by a drying drum; e) winding a resilient wound element disposed at the mid point of said overlap of said aluminum ribbon, thereby to form a duct; and f) forming ridges on said aluminum ribbon by causing engagement of multiple ridged break-down wheels with a modified roller, while said aluminum ribbon is in between them, wherein said ridged break-down wheel is supported by a mounting arm external to said mandrel. ### Claim 18 (depends on 17) The method of claim 17, wherein said step e) of winding a wire includes the sub-step of aligning said wire with the overlap of said first ribbon so that the wire is approximately centered at the mid-point of the overlap of said aluminum ribbon. ### Claim 19 (depends on 17) The method of claim 17, wherein said step c) of winding said aluminum ribbon and said step e) of winding the wire, are performed by rotating said mandrel as said aluminum ribbon and the wire, are respectively taken up by said mandrel, continuously and with predetermined phase differences therebetween, with respect to the rotation of said mandrel. ### Claim 20 (depends on 17) The method of claim 17, wherein said step c) of winding said aluminum ribbon and said step e) of winding the wire are performed continuously and with a first preselected phase difference therebetween, with respect to the rotation of said mandrel. ### Claim 21 (depends on 17) The method of claim 17, wherein said modified roller of said step f) of forming ridges on said aluminum ribbon, is modified by adding circumferential grooves to the distal end of said roller, and wherein said grooves match said ridges on said break-down wheels, and wherein said grooves and said ridges mesh with each other by engagement, while said aluminum ribbon is in between them, thus forming said closely and evenly-spaced ridges on said aluminum ribbon. ### Claim 22 (depends on 17) The method of claim 17, wherein said arm supporting said break-down wheel is adjustably moved into position during the setup of said manufacturing process, and once established is maintained during production. ### Claim 23 (depends on 17) The method of claim 17, and further including, after said step e) of winding, the additional step of imparting to at least a portion of said duct, a polygonal cross-sectional configuration. ### Claim 24 (depends on 23) The method of claim 23, and wherein said additional step of imparting a polygonal cross-sectional configuration to at least a portion of said duct comprises imparting thereto a square or rectangular cross-sectional configuration. ### Claim 25 (depends on 17) The method of claim 17, wherein said aluminum ribbon maintains a substantially constant and identical tension, while being wrapped around said mandrel, in the range of 75-80 kgf, and wherein said wire is also maintained in the same said tension of said aluminum ribbon. ### Claim 26 (depends on 17) The method of claim 17, wherein said mandrel comprises a plurality of rollers each mounted so as to be individually rotatable on a fixed plate at a predetermined angle, each comprising a set of precision-shaped grooves for accepting said wire, and wherein said grooves are precision-spaced apart in order to accept a predetermined flow of said wire, established by said predetermined angle of said rollers, onto said mandrel, such that said wire becomes a spiral form within said duct being drawn off said mandrel in an automatic fashion. ### Claim 27 (depends on 26) The method of claim 26 wherein each of said rollers is mounted on said plate so as to provide a flexible spring-like action which absorbs any irregularities in said tension and irregularities associated with said wire and said ribbons.