# US 10,479,031 B2 · Device and method for infiltrating a fiber preform > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,479,031 B2 - Document ID: US10479031B2 - Status: Granted - Kind: B2 - Application number: 14/652,291 - Filed: 2013-12-06 - Published: 2015-12-03 - Granted: 2019-11-19 - Earliest claimed: 2012-12-21 - Assignees: Thyssenkrupp Federn Und Stabilisatoren GmbH; thyssenkrupp AG - Applicants: ThyssenKrupp Federn und Stabilisatoren GmbH; ThyssenKrupp AG - Inventors: Werner Hufenbach; Martin Lepper; Jens Werner; Christian Koehler; André Bartsch - Web page: https://patentgrep.com/patent/US10479031B2 ## CPC - B29C 70/446: {Moulding structures having an axis of symmetry or at least one channel, e.g. tubular structures, frames} - B29C 70/48: and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] {, e.g. by vacuum} - B29C 70/542: {Placing or positioning the reinforcement in a covering or packaging element before or during moulding, e.g. drawing in a sleeve} - B29K 2105/08: of continuous length, e.g. cords, rovings, mats, fabrics, strands or yarns - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS ## Abstract The invention relates to a method and a device for infiltrating a fiber preform of a component of fiber composite material with a matrix material. On the method side, it is proposed that an elastic coating (3) is applied onto the fiber preform (1, 23, 37), wherein the elastic coating (3) is widened to form a gap space (22) between the fiber preform (1) and the coating (3). The matrix material (21) is then fed into the gap space (22) and the elastic coating (3) is subsequently pressed against the fiber preform (1, 23, 37). On the device side, it is claimed that an elastic coating (3) is arranged on the fiber preform (1, 23, 37) and means are provided, which are in operative connection with the elastic coating (3), by which the coating (3) can be widened while forming a gap space (22) between the fiber preform (1, 23, 37) and the coating (3). A matrix material (21) can be fed into the gap space (22) and the coating (3) can be pressed against the fiber preform (1, 23, 37). ## Claims ### Claim 1 A method of infiltrating with a matrix material a fiber preform for a component of fiber composite material, wherein the method comprises: (a) applying an elastic overlay to the fiber preform, the fiber preform being dry, (b) expanding the elastic overlay by creating an unoccupied gap that surrounds the fiber preform between a surface of the fiber preform and the elastic overlay, (c) introducing the matrix material directly into the unoccupied gap through a casting line which comprises a casting-line connection piece connected to the elastic overlay to distribute the matrix material over the surface of the fiber preform, and (d) thereafter pressing the elastic overlay onto the fiber preform to cause the matrix material to infiltrate the fiber preform, wherein a tubular, elastic overlay is used, and wherein the tubular elastic tube is applied to the fiber preform such that the elastic tube is drawn over a hollow-profile auxiliary body. ### Claim 2 (depends on 1) The method of claim 1, wherein an internal, pressure-tight closed system for generating pressure in the region between the overlay and the fiber preform is created between the fiber preform and the overlay. ### Claim 3 (depends on 2) The method of claim 2, wherein prior to introduction of matrix material into the unoccupied gap, the fiber preform is evacuated by the internal pressure system. ### Claim 4 (depends on 1) The method of claim 1, wherein an external, pressure-tight closed system is created between a pressure chamber and the overlay. ### Claim 5 (depends on 1) The method of claim 1, wherein the unoccupied gap between the fiber preform and the overlay is created such that positive pressure is established in an internal, pressure-tight closed system in relation to a pressure in an external, pressure-tight system. ### Claim 6 (depends on 1) The method of claim 1, wherein the elastic overlay is pressed onto the fiber preform by creating a positive pressure in an external, pressure-tight closed system in relation to a pressure in an internal, pressure-tight closed system. ### Claim 7 A method of infiltrating with a matrix material a fiber preform for a component of fiber composite material, wherein the method comprises: (a) surrounding the fiber preform with an elastic overlay, (b) expanding the elastic overlay by creating an unoccupied gap that surrounds the fiber preform between a surface of the fiber preform and the overlay, (c) introducing the matrix material directly into the unoccupied gap and distributing the matrix material 360° over the surface of the fiber preform, and (d) thereafter pressing the elastic overlay onto the fiber preform to cause the matrix material to infiltrate the fiber preform, wherein a tubular, elastic overlay is used, and wherein the elastic tube is applied to the fiber preform such that the elastic tube is drawn over a hollow-profile auxiliary body. ### Claim 8 (depends on 7) The method of claim 7, wherein the fiber preform is introduced into a clear opening of the auxiliary body. ### Claim 9 (depends on 7) The method of claim 7, wherein the fiber preform over which the overlay has been placed is placed on a mold core prior to expanding of the overlay. ### Claim 10 (depends on 7) The method of claim 7, wherein the fiber preform is placed on a mold core prior to placing the elastic overlay on the fiber preform. ### Claim 11 (depends on 10) The method of claim 10, wherein the overlay connected to the mold core has a pressure-tight connection to the mold core. ### Claim 12 (depends on 7) The method of claim 7, wherein the fiber preform is arranged in the tubular, elastic overlay by means of an intake device. ### Claim 13 (depends on 12) The method of claim 12, wherein the intake device has a hollow-profile-shaped auxiliary body. ### Claim 14 (depends on 7) The method of claim 7, wherein an external, pressure-tight closed system is created between a pressure chamber and the overlay. ### Claim 15 (depends on 7) The method of claim 7, wherein the unoccupied gap between the fiber preform and the overlay is created such that positive pressure is established in an internal, pressure-tight closed system in relation to a pressure in an external, pressure-tight system. ### Claim 16 (depends on 7) The method of claim 7, wherein the elastic overlay is pressed onto the fiber preform by creating a positive pressure in an external, pressure-tight closed system in relation to a pressure in an internal, pressure-tight closed system. ### Claim 17 (depends on 7) The method of claim 7, wherein the fiber preform is rod-shaped. ### Claim 18 (depends on 17) The method of claim 17, wherein prior to (b) the preform is wound onto a cylindrical mold core. ### Claim 19 (depends on 18) The method of claim 18, wherein the cylindrical mold core comprises a spiral-shaped groove so that a shape of the wound fiber preform is fit to a shape of a coil spring. ### Claim 20 (depends on 7) The method of claim 7, wherein the method is used to produce a coil spring.