# US 10,309,420 B2 · Fan > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,420 B2 - Document ID: US10309420B2 - Status: Granted - Kind: B2 - Application number: 15/394,461 - Filed: 2016-12-29 - Published: 2017-04-20 - Granted: 2019-06-04 - Earliest claimed: 2012-05-16 - Assignees: Dyson Technology Limited - Applicants: Dyson Technology Limited - Inventors: Jack Johnson; Jean-Baptiste Blanc - Web page: https://patentgrep.com/patent/US10309420B2 ## CPC - F04D 29/664: {by means of sound absorbing material} - F04D 17/00: Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps (F04D21/00 takes precedence) - F04D 25/06: the pump being electrically driven (F04D25/08 takes precedence) - F04D 25/08: the working fluid being air, e.g. for ventilation - F04D 25/16: Combinations of two or more pumps {; Producing two or more separate gas flows} - F04D 29/281: {for fans or blowers} - F04D 29/325: {for axial flow fans (blade mountings F04D29/34, blades F04D29/38)} - F04D 29/403: {especially adapted for elastic fluid pumps} - F04D 29/4226: {Fan casings} - F04D 29/663: {Sound attenuation} - F04D 29/665: {by means of resonance chambers or interference} - F04F 5/16: displacing elastic fluids - F04F 5/46: Arrangements of nozzles - H02K 5/24: specially adapted for suppression or reduction of noise or vibrations - H02K 7/14: Structural association with mechanical loads, e.g. with hand-held machine tools or fans (with fan or impeller for cooling the machine H02K9/06) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F04F: PUMPING OF FLUID BY DIRECT CONTACT OF ANOTHER FLUID OR BY USING INERTIA OF FLUID TO BE PUMPED {(evacuating by sorption F04B)}; SIPHONS {(conveying materials in bulk by flows of gas, liquid of foam B65G53/00)} - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract A fan for generating an air current includes a body having an air inlet, and a nozzle connected to the body. The nozzle includes an interior passage for receiving an air flow from the body and an air outlet from which the air flow is emitted from the fan. The interior passage extends about an opening or bore through which air from outside the nozzle is drawn by air emitted from the air outlet. The body includes a duct having an air inlet and an air outlet, an impeller located within the duct for drawing the air flow through the duct, and a motor for driving the impeller. An annular guide member extends about the duct for guiding air from the air inlet of the body to the air inlet of the duct. The guide member defines with the duct an annular noise suppression cavity. ## Claims ### Claim 1 A fan for generating an air current, comprising: a body comprising an air inlet; and a nozzle connected to the body; the nozzle comprising an interior passage for receiving an air flow from the body and at least one air outlet from which the air flow is emitted from the fan, the interior passage extending about an opening through which air from outside the nozzle is drawn by air emitted from the at least one air outlet; the body comprising a duct having an air inlet and an air outlet, an impeller located within the duct for drawing the air flow through the duct, and a motor for rotating the impeller about a rotational axis, the body defining an air flow path extending from the air inlet of the body to the air outlet of the duct; wherein the body further comprises an annular guide member extending about the duct for guiding air from the air inlet of the body to the air inlet of the duct, and wherein the guide member defines with the duct at least part of an annular noise suppression cavity, wherein the duct comprises an inner wall and an outer wall extending about the inner wall, and wherein a portion of the inner wall of the duct is perforated and lined internally with sound-absorbing material, and wherein the perforated portion of the inner wall is frusto-conical in shape, and tapers towards the outlet of the duct. ### Claim 2 (depends on 1) The fan of claim 1, wherein the noise suppression cavity has an inlet at least partially defined by the guide member. ### Claim 3 (depends on 2) The fan of claim 2, wherein the inlet of the noise suppression cavity is located between the air inlet of the duct and the guide member. ### Claim 4 (depends on 1) The fan of claim 1, wherein the guide member is inclined relative to the rotational axis of the impeller. ### Claim 5 (depends on 1) The fan of claim 1, wherein the guide member is conical in shape. ### Claim 6 (depends on 1) The fan of claim 1, wherein the guide member depends from an annular rib extending between the body and the duct. ### Claim 7 (depends on 1) The fan of claim 1, wherein the air inlet of the body comprises an array of apertures which extends about the guide member. ### Claim 8 (depends on 1) The fan of claim 1, wherein the guide member defines in part a tortuous air flow path between the air inlet of the body and the air inlet of the duct. ### Claim 9 (depends on 1) The fan of claim 1, wherein the body comprises an annular sound-absorbing member located beneath the guide member. ### Claim 10 (depends on 9) The fan of claim 9, wherein the guide member and the annular sound-absorbing member are concentric. ### Claim 11 (depends on 1) The fan of claim 1, wherein a section of the duct adjacent the perforated portion of the inner wall houses a diffuser. ### Claim 12 (depends on 11) The fan of claim 11, wherein the diffuser is configured to support the inner wall within the outer wall. ### Claim 13 (depends on 1) The fan of claim 1, wherein the inner wall of the duct forms at least part of a motor housing for housing the motor. ### Claim 14 (depends on 1) The fan of claim 1, wherein the duct is mounted on an annular seat located within the body, the body comprising an annular seal in sealing engagement with the duct and the seat. ### Claim 15 (depends on 14) The fan of claim 14, wherein the seal is a foam annular seal. ### Claim 16 (depends on 1) The fan of claim 1, wherein the impeller is a mixed flow impeller. ### Claim 17 (depends on 1) The fan of claim 1, wherein the impeller comprises a conical hub connected to the motor, and a plurality of blades connected to the hub, each blade comprising a leading edge located adjacent the air inlet of the impeller housing, a trailing edge, an inner side edge connected to and extending partially about the outer surface of the hub, an outer side edge located opposite to the inner side edge, and a blade tip located at the intersection of the leading edge and the outer side edge, and wherein the leading edge comprises an inner portion located adjacent the hub, and an outer portion located adjacent the blade tip, and wherein the inner portion is swept rearwardly from the hub to the outer portion, and the outer portion is swept forwardly from the inner portion to the blade tip. ### Claim 18 (depends on 1) The fan of claim 1, wherein the air outlet of the duct protrudes from the body into the interior passage of the nozzle.