FAN

• US 20130309065A1
• Filed: 05/16/2013
• Published: 11/21/2013
• Est. Priority Date: 05/16/2012
• Status: Active Grant

• Current Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Original Assignee: Dyson Technology Limited (Beeswax Holdings UK Limited)
• Inventors: JOHNSON, Jack, BLANC, Jean-Baptiste
• Granted Patent: US 9,568,021 B2
• Time in Patent Office: Days
• US Class Current: 415/119
• CPC Class Codes: F04D 25/06 the pump being electrically driven F04D25/08 takes precedence
• CPC Class Codes: F04D 25/08 the working fluid being air, e.g. for ventilation
• CPC Class Codes: F04D 25/16 Combinations of two or more pumps ; Producing two or more separate gas flows
• CPC Class Codes: F04D 29/083 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/281 for fans or blowers
• CPC Class Codes: F04D 29/325 for axial flow fans blade mountings F04D29/34, blades F04D29/38
• CPC Class Codes: F04D 29/403 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/4226 Fan casings
• CPC Class Codes: F04D 29/664 by means of sound absorbing material
• CPC Class Codes: F04D 29/665 by means of resonance chambers or interference
• CPC Class Codes: F04F 5/16 displacing elastic fluids
• CPC Class Codes: F04F 5/46 Arrangements of nozzles

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. A noise suppression cavity is located beneath the air inlet of the duct. The cavity has an inlet which is located beneath, and is preferably concentric with, the air inlet of the duct.

Claims

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 said 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 driving the impeller, 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 a noise suppression cavity located beneath the air inlet of the duct, the cavity having an inlet which is located beneath the air inlet of the duct.

2. The fan of claim 1, wherein the body comprises at least one wall at least partially delimiting the noise suppression cavity, and wherein the inlet of the cavity is located in said at least one wall of the body.

3. The fan of claim 1, wherein the body comprises a lower section and an upper section which is mounted on the lower section for movement relative thereto, and wherein the upper section of the body has a bottom wall which partially delimits the noise suppression cavity.

4. The fan of claim 3, wherein the bottom wall of the upper section of the body is concave in shape.

5. The fan of claim 1, wherein the body comprises an annular sound absorbing member located between the duct and the noise suppression cavity.

6. The fan of claim 5, wherein the annular sound absorbing member is concentric with the inlet of the noise suppression cavity.

7. The fan of claim 6, wherein the body comprises a sheet of sound absorbing material disposed over the annular sound absorbing member.

8. The fan of claim 1, wherein the body 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.

9. The fan of claim 8, 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.

10. The fan of claim 9, wherein the noise suppression cavity is located beneath said tortuous air flow path.

11. The fan of claim 8, wherein the guide member is inclined relative to the rotational axis of the impeller.

12. The fan of claim 8, wherein the guide member is substantially conical in shape.

13. The fan of claim 8, wherein the guide member depends from an annular rib extending between the body and the duct.

14. The fan of claim 1, wherein the body comprises an annular noise suppression cavity extending about the duct.

15. The fan of claim 14, wherein the outer surface of the duct partially delimits the annular noise suppression cavity.

16. The fan of claim 1, wherein the air inlet of the body comprises an array of apertures which extends about the duct.

17. The fan of claim 1, 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.

18. The fan of claim 17, wherein the perforated portion of the inner wall is frusto-conical in shape, and tapers towards the outlet of the duct.

19. The fan of claim 17, wherein a section of the duct adjacent the perforated portion of the inner wall houses a diffuser.

20. The fan of claim 17, wherein the inner wall of the duct forms at least part of a motor housing for housing the motor.

21. 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.

22. The fan of claim 21, wherein the seal is a foam annular seal.

23. The fan of claim 1, wherein the impeller is a mixed flow impeller.

24. The fan of claim 1, wherein the impeller comprises a substantially 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.

25. The fan of claim 1, wherein the air outlet of the duct protrudes from the body into the interior passage of the nozzle.

26. The fan of claim 1, wherein the inlet of the cavity is concentric with the air inlet of the duct.