# US 11,111,930 B2 · Ceiling fan blade > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,111,930 B2 - Document ID: US11111930B2 - Status: Granted - Kind: B2 - Application number: 16/458,333 - Filed: 2019-07-01 - Published: 2020-01-16 - Granted: 2021-09-07 - Earliest claimed: 2018-07-10 - Assignees: Hunter Fan Company - Applicants: Hunter Fan Company - Inventors: Bobby Neal Norwood; Charles William Botkin - Web page: https://patentgrep.com/patent/US11111930B2 ## CPC - F04D 29/384: {characterised by form} - F04D 25/088: {Ceiling fans} - F04D 29/34: Blade mountings {(for axial flow compressors F04D29/322)} - F04D 29/286: {multi-stage rotors} - F04D 29/324: {Blades} - F04D 29/38: Blades {(for axial flow compressors F04D29/324)} - F04D 29/388: {characterised by construction} - F04D 29/544: {Blade shapes} - F04D 29/547: {having a special shape in order to influence fluid flow} - F05D 2240/301: Cross-sectional characteristics - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A ceiling fan or blade thereof can include a fan motor for rotating the blade. The blade can include an airfoil body having an outer surface extending between a leading edge and a trailing edge, and a root and a tip. The blade can be separated into three distinct cross sections including a first cross section as a lifting cross section, a second cross section as a flat cross section, and a third cross section as a transition section between the first and second cross sections. ## Claims ### Claim 1 A blade for a ceiling fan having a fan motor rotating at least one blade iron, the blade comprising: an airfoil body having an outer surface extending between a leading edge and a trailing edge to define a chord-wise direction, and separating the outer surface into an upper surface and a lower surface, and the outer surface extending between a root and a tip to define a span-wise direction; and a blade iron mount provided on the root; wherein the airfoil body comprises at least three distinct cross sections in the span-wise direction: a first cross section comprising a flat lower surface with a lifting cross section; a second cross section comprising the flat lower surface and a flat upper surface; and a third cross section located between and transitioning from the first to the second cross sections. ### Claim 2 (depends on 1) The blade of claim 1 wherein the first cross section includes a first angle of attack and the second cross section includes a second angle of attack different than the first cross section, such that the body twists about the third cross section. ### Claim 3 (depends on 1) The blade of claim 1 wherein the lifting cross section is one of a flat bottom airfoil, a symmetric airfoil, a semi-symmetrical airfoil, or an under-camber airfoil. ### Claim 4 (depends on 3) The blade of claim 3 wherein the lifting cross section includes the flat bottom airfoil. ### Claim 5 (depends on 1) The blade of claim 1 wherein the tip includes a front surface having a convex shape. ### Claim 6 (depends on 5) The blade of claim 5 wherein the root includes a rear surface that is flat. ### Claim 7 (depends on 1) The blade of claim 1 wherein the blade iron mount is provided on the upper surface of the airfoil body at the root. ### Claim 8 (depends on 7) The blade of claim 7 wherein the blade iron mount is a gasket. ### Claim 9 (depends on 1) The blade of claim 1 wherein the blade iron mount is provided on the lower surface of the airfoil body. ### Claim 10 (depends on 1) The blade of claim 1 wherein second cross section is provided at the tip, the first cross section is spaced from the tip, and the third cross section is provided therebetween. ### Claim 11 (depends on 10) The blade of claim 10 wherein the first cross section extends from the root. ### Claim 12 (depends on 11) The blade of claim 11 wherein the third cross section is spaced at least 3% of a length of the blade from the tip in the span-wise direction. ### Claim 13 (depends on 1) The blade of claim 1 wherein the airfoil body further includes a fourth cross section located at the root including the flat lower surface and the flat upper surface. ### Claim 14 (depends on 13) The blade of claim 13 further comprising a fifth cross section located between and transitioning between the first cross section and the fourth cross section. ### Claim 15 A ceiling fan assembly comprising: a motor including a rotatable rotor and a stationary stator, with the stator configured to drive the rotor; at least one blade coupled to the rotor and having an airfoil body including an outer surface extending between a leading edge and a trailing edge to define a chord-wise direction, and separating the outer surface into an upper surface and a lower surface, and the outer surface extending between a root and a tip to define a span-wise direction; wherein the airfoil body comprises at least three distinct cross sections in the span-wise direction: a first cross section comprising a airfoil cross section; a second cross section comprising a flat lower surface and a flat upper surface; and a third cross section located between and transitioning from the first to the second cross sections. ### Claim 16 (depends on 15) The ceiling fan assembly of claim 15 wherein the first cross section is provided at the root and the second cross section is provided at the tip. ### Claim 17 (depends on 15) The ceiling fan assembly of claim 15 wherein the airfoil cross section is one of a flat bottom airfoil, a symmetric airfoil, a semi-symmetrical airfoil, or an under-camber airfoil. ### Claim 18 (depends on 15) The ceiling fan assembly of claim 15 wherein the third cross section is spaced at least 3% of a length of the blade from the tip in the span-wise direction. ### Claim 19 (depends on 15) The ceiling fan assembly of claim 15 wherein the airfoil body further includes a fourth cross section at the root including the flat upper surface and the flat lower surface and a fifth cross section located between and transitioning from the first cross section to the fourth cross section. ### Claim 20 A blade for a ceiling fan comprising: an airfoil body having an outer surface extending between a leading edge and a trailing edge to define a chord-wise direction, and separating the outer surface into an upper surface and a lower surface, and the outer surface extending between a root and a tip to define a span-wise direction; wherein the airfoil body comprises at least three distinct cross sections along the span-wise direction: a first cross section comprising an airfoil cross section; a second cross section comprising a flat upper surface and a flat lower surface; and a third cross section located between and transitioning between the first cross section and the second cross section.