# US 10,371,165 B2 · Fan blade composite ribs > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,165 B2 - Document ID: US10371165B2 - Status: Granted - Kind: B2 - Application number: 15/032,526 - Filed: 2014-10-09 - Published: 2016-09-15 - Granted: 2019-08-06 - Earliest claimed: 2013-10-30 - Assignees: United Technologies Corporation - Applicants: United Technologies Corporation - Inventors: Michael A. Weisse; Kwan Hui - Web page: https://patentgrep.com/patent/US10371165B2 ## CPC - F04D 29/388: {characterised by construction} - F01D 5/147: {Construction, i.e. structural features, e.g. of weight-saving hollow blades (F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18)} - F01D 5/282: {Selecting composite materials, e.g. blades with reinforcing filaments} - F04D 29/023: {especially adapted for elastic fluid pumps} - F04D 29/325: {for axial flow fans (blade mountings F04D29/34, blades F04D29/38)} - F05D 2220/36: specially adapted for the fan of turbofan engines - F05D 2250/75: given by its similarity to a letter, e.g. T-shaped - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A fan blade has a blade body, a composite rib and a cover. The blade body extends from a blade root to an opposed blade tip along a longitudinal axis. The blade body defines a leading edge and a trailing edge. A first airfoil surface extends from the leading edge to the trailing edge A pocket is defined between the leading edge, the trailing edge, the blade root, and the blade tip. The pocket has a bottom surface that opposes the first airfoil surface across the blade body. The composite rib is disposed in the pocket. The cover is mounted to the composite rib and the blade body to form a second airfoil surface opposed to the first airfoil surface. ## Claims ### Claim 1 A fan blade, comprising: a blade body extending from a blade root to an opposed blade tip along a longitudinal axis, wherein the blade body defines a leading edge and a trailing edge, a first airfoil surface extending from the leading edge to the trailing edge, and a pocket defined between a plurality of edges including, the leading edge, the trailing edge, a first edge at the blade root and a second edge at the blade tip, the pocket having a bottom surface that extends between the plurality of edges and faces an inside of the pocket, wherein the bottom surface opposes the first airfoil surface across the blade body; a cover mounted to the blade body to form a second airfoil surface opposed to the first airfoil surface, wherein the cover encloses the pocket, and a composite rib disposed in the pocket, wherein the composite rib includes a front surface and a back surface, the front surface being adhered to the bottom surface of the pocket and the back surface being adhered to the cover, and wherein the composite rib is cross shaped to define a first pair of edges facing the leading edge of the pocket and a second pair of edges facing the trailing edge of the pocket. ### Claim 2 (depends on 1) The fan blade as recited in claim 1, wherein the composite rib includes a weight reducing cavity that projects from the back surface and through the front surface of the composite rib, the cavity defining a groove that includes a first pair of edge openings facing the leading edge of the pocket and a second pair of edge openings facing the trailing edge of the pocket. ### Claim 3 (depends on 2) The fan blade as recited in claim 2, wherein the groove is cross shaped. ### Claim 4 (depends on 1) The fan blade as recited in claim 1, wherein the composite rib is configured to resist shear and tension forces acting on the cover in order to secure the cover to the blade body. ### Claim 5 (depends on 1) The fan blade as recited in claim 1, wherein the blade body includes a recessed lip defined around its perimeter. ### Claim 6 (depends on 5) The fan blade as recited in claim 5, wherein an interior surface of the cover is adhered to the blade body on the recessed lip, wherein the recessed lip is configured to allow the cover to be mounted flush with the blade body. ### Claim 7 (depends on 1) The fan blade as recited in claim 1, wherein the pocket of the blade body is at least partially filled with lightweight filler material. ### Claim 8 (depends on 1) The fan blade as recited in claim 1, wherein the composite rib extends from a leading edge side of the pocket to a trailing edge side of the pocket. ### Claim 9 (depends on 8) The fan blade as recited in claim 8, wherein the composite rib is adhered to the leading edge side of the pocket and the trailing edge side of the pocket. ### Claim 10 (depends on 1) The fan blade as recited in claim 1, wherein the composite rib includes lightweight filler material. ### Claim 11 A fan blade, comprising: a blade body extending from a blade root to an opposed blade tip along a longitudinal axis, wherein the blade body defines a leading edge and a trailing edge, a first airfoil surface extending from the leading edge to the trailing edge, and a pocket defined between a plurality of edges including the leading edge, the trailing edge, a first edge at the blade root and a second edge at the blade tip, the pocket having a bottom surface that extends between the plurality of the edges and faces an inside of the pocket, wherein the bottom surface opposes the first airfoil surface across the blade body, a cover mounted to the composite rib and the blade body to form a second airfoil surface opposed to the first airfoil surface, wherein the cover encloses the pocket, and a composite rib disposed in the pocket, wherein the composite rib includes a front surface and a back surface, the front surface being adhered to the bottom surface of the pocket and the back surface being adhered to the cover, and wherein the composite rib is cross shaped to define a first pair of edges facing the leading edge of the pocket and a second pair of edges facing the trailing edge of the pocket. ### Claim 12 (depends on 11) The fan blade as recited in claim 11, wherein the composite rib includes a weight reducing cavity that projects from the back surface and through the front surface of the composite rib, the cavity defining a cross-shaped groove that includes a first pair of edge openings facing the leading edge of the pocket and a second pair of edge openings facing the trailing edge of the pocket. ### Claim 13 (depends on 12) The fan blade as recited in claim 12, wherein the groove of the composite rib corresponding to a shape of the blade rib, wherein the blade rib is adhered to the composite rib within the groove to increase a surface area of the composite rib in contact with the blade rib. ### Claim 14 (depends on 11) The fan blade as recited in claim 11, wherein the blade rib is integral with the blade body. ### Claim 15 (depends on 12) The fan blade as recited in claim 12, wherein the groove is cross shaped.