GB2283534A

GB2283534A - A fan housing

Info

Publication number: GB2283534A
Application number: GB9419871A
Authority: GB
Inventors: John Joseph Grainger; Benedict Michael Kearney
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-11-01
Filing date: 1994-10-03
Publication date: 1995-05-10
Also published as: GB9419871D0; IE930834A1

Abstract

A fan housing 1 having an axial fan 3 located therein is suitable for mounting between a pair of ducts 4 and 5 of a duct run 2 for urging air or other fluid through the duct run 2. The fan housing 1 comprises a central cylindrical member 20 having a bore 22 extending therethrough within which the axial fan 3 is located. Mounting flanges 23 extend around and radially outwardly of the central member 20 and define abutting faces 25 for abutting corresponding flanges 11 of the ducts 4 and 5 for sealably engaging the flanges 11. The peripheral edges 27 of the mounting flanges 23 are of square shape and are of size and shape corresponding to the peripheral edges 28 of the flanges 11 to facilitate securing the fan housing 1 directly onto the ducts 4 and 5. <IMAGE>

Description

"A fan housing" The invention relates to a fan housing, and in particular to a fan housing for accommodating a fan and for mounting the fan in a duct run where the duct run comprises ducts having three or more sides. The invention also relates to a duct run comprising the fan housing.

In air conditioning installations and other systems where air or other fluids are to be moved, it is common to provide duct runs through which the air or fluid is transferred. In many cases, such duct runs comprise ducts having four or more sides, for example, four sided ducts of square or rectangular transverse cross sectional area. Such ducts of square and rectangular cross sectional area are in common usage, in particular, in air conditioning and other installations where air is to be transferred. One or more fans are required in the duct run in order to transfer the air or fluid through the duct run. In general, axial flow fans, and mixed axial and centrifugal flow fans are desirable. Such fans comprise a cylindrical housing having a through bore extending axially therethrough within which the axial flow fan is located.In order to connect such housings into a duct run, because of the circular transverse cross section of the fan housing, it is necessary to provide adaptor ducts at each end of the fan housing for connecting the respective ends of the fan housing to the respective upstream and downstream ducts. Such adaptor ducts, in general, are of sheet material and form a bore which at one end is of circular transverse cross section to correspond with the bore of the fan housing, and at the other end is of square or rectangular transverse cross section or of other appropriate transverse cross section to correspond to the transverse cross section of the duct of the duct run. The transition of the bore from circular to square, rectangular or other appropriate transverse cross section, in general, is gradual.Because of the relatively gradual transition from round to the appropriate cross section of the duct, such adaptor ducts, in general, are relatively long, and in general, are relatively expensive. Thus, to fit a fan housing comprising an axially flow fan or a mixed axial and centrifugal flow fan into a duct run, generally requires removing a considerable length of the duct run to accommodate the fan housing and the adaptor ducts on each end of the fan housing, and furthermore, because of the relatively high cost of such adaptor ducts, the cost of installing such a fan in a square or rectangular duct, or duct of transverse cross section other than circular can be relatively expensive. Indeed, similar problems may arise where a centrifugal fan is being connected into a duct run.

There is therefore a need for a fan housing which overcomes these problems.

The present invention is directed towards providing such a fan housing and a duct run comprising the fan housing.

According to the invention, there is provided a fan housing for accommodating a fan and for mounting the fan in a duct run between an upstream duct and a downstream duct of the duct run, the ducts being of the type having at least three sides, the housing comprising an elongated central member having a through bore extending therethrough for accommodating the fan and defining a central longitudinal axis, the through bore co-operating with the fan for facilitating the urging of fluid therethrough by the fan, and a pair of axially spaced apart outwardly extending mounting flanges located at respective opposite ends of the central member for connecting the fan housing to the respective upstream and downstream ducts of the duct run, each mounting flange having a duct abutting face extending from and circumferentially around the through bore for engaging the corresponding adjacent duct with a substantially fluid tight seal.

Preferably, the abutting face extends radially relative to the central axis. Advantageously, each mounting flange extends radially from the central member.

In one embodiment of the invention each abutting face terminates in a peripheral edge extending circumferentially around the central member, the peripheral edge substantially defining a peripheral edge of a corresponding mounting means on the corresponding duct of the duct run.

In one embodiment of the invention the peripheral edge of at least one abutting face defines a square. In another embodiment of the invention the peripheral edge of both abutting faces defines a square.

Alternatively, the peripheral edge of at least one abutting face defines a rectangle. In another embodiment of the invention the peripheral edge of both abutting faces defines a rectangle.

In a further embodiment of the invention a receiving means is provided on each mounting flange for receiving a securing means for securing the mounting flange to the corresponding duct. Preferably, each receiving means comprises a receiving lip extending from the corresponding mounting flange adjacent the peripheral edge thereof, the receiving lip being directed towards the other of the two mounting flanges. Advantageously, each receiving lip extends completely around the peripheral edge of its corresponding mounting flange.

In one embodiment of the invention the through bore diverges outwardly at at least one of its ends for minimizing turbulence in the air flowing therethrough.

Preferably, the through bore diverges outwardly at both of its opposite ends. Advantageously, each diverging portion of the through bore is formed by radiusing the area where the inner surface of the through bore joins the corresponding duct abutting face.

In another embodiment of the invention the through bore is of circular transverse cross section, the diameter of the through bore being just greater than the diameter of the fan blades of the fan to be located therein. Preferably, the central member is an elongated cylindrical member.

In another embodiment of the invention a mounting area is provided on the abutting face of one of the mounting flanges for engaging a mounting bracket for mounting and locating the fan in the through bore.

Preferably, a cable accommodating opening extends through one of the mounting flanges for accommodating a cable of the fan therethrough. Preferably, the cable accommodating opening is provided through the abutting face of the mounting flange. Advantageously, the cable accommodating opening is located in an area of the abutting face adjacent a corner of the peripheral edge thereof.

In one embodiment of the invention a fan is located in the through bore.

Preferably, a mounting bracket connected to the fan housing and to the fan mounts the fan in the through bore.

Advantageously, the mounting bracket is connected to the mounting area of the abutting face of one of the mounting flanges.

In one embodiment of the invention at least two mounting brackets are provided, the mounting brackets extending from the fan in diametrically opposite directions. Preferably, each mounting bracket is connected to the abutting face of the mounting flange at a position intermediate the through bore and a corner of the peripheral edge of the abutting face on a diagonal extending between opposite corners of the peripheral edge of the abutting face. Advantageously, four mounting brackets are provided extending from the fan, the mounting brackets being equi-spaced angularly around the fan.

In one embodiment of the invention the fan is an electrically powered fan.

Preferably, the fan is driven by an electrically powered motor, the motor and fan being axially aligned.

In one embodiment of the invention the fan is an axial flow fan. In an alternative embodiment of the invention the fan is a mixed axial and centrifugal flow fan. In a still further alternative embodiment of the invention the fan is a centrifugal fan.

Additionally the invention provides a duct comprising an upstream duct and a downstream duct, and the fan housing according to the invention mounted between the upstream and downstream ducts.

The invention will be more clearly understood from the following description of a preferred embodiment thereof, which is given by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a fan housing according to the invention, Fig. 2 is a cross sectional side elevational view on the line II-II of Fig. 1, Fig. 3 is a perspective view of the fan housing of Fig. 1 illustrating an axial flow fan mounting therein, Fig. 4 is a perspective view of a duct run also according to the invention illustrated incorporating the fan housing of Fig. 1, Fig. 5 is an exploded perspective view of the duct run of Fig. 4, Fig. 6 is a cross sectional side elevational view of a detail of the duct run of Fig. 4, Fig. 7 is a perspective view of the detail of Fig.

6, and Fig. 8 is a perspective view of portion of the detail of Fig. 6.

Referring to the drawings there is illustrated a fan housing according to the invention indicated generally by the reference numeral 1 for mounting in a duct run, also according to the invention and indicated generally by the reference numeral 2. A portion of the duct run 2 which is typical of the type which would be used in an air conditioning system is illustrated in Figs. 4 to 8, and in particular, in Figs. 4 to 6. An axial flow fan 3 as will be described below is located in the fan housing 1 for transferring air through the duct run 2.

Before describing the fan housing 1 in detail, the duct run 2 will first be described.

The duct run 2 comprises a pair of ducts, namely, an upstream duct 4 and a downstream duct 5 between which the fan housing 1 is mounted. Each duct 4 and 5 is of square transverse cross section, and is formed by four walls 7 of sheet metal. The ducts 4 and 5 terminate in ends 8 which are attached by mounting means, namely, mounting members 9 which are joined together by corner members 10. The mounting members 9 and the corner members 10 together form a circumferentially extending flange 11 for sealably abutting the fan housing 1 as will be described below. The mounting members 9 and corner members 10 will be well known to those skilled in the art. Briefly, the mounting members 9 are formed from folded sheet metal, and define a bore 12 of rectangular cross section for receiving the corner members 10.The mounting members 9 are folded to form slots 14 for receiving the ends 8 of the walls 7 of the duct 4 and 5. A plurality of securing brackets 17 as will be described below are provided for securing the respective ducts 4 and 5 to the fan housing 1.

Returning now to the fan housing 1, the fan housing 1 is of fibreglass material and comprises an elongated central cylindrical member 20 having a through bore 22 of circular transverse cross section extending therethrough for accommodating the axial flow fan 3. A pair of axially spaced apart mounting flanges 23 extend radially outwardly from and completely around the central member 20. Each mounting flange 23 is provided with an abutting face 25 which extends radially outwardly of the through bore 22 for abutting a corresponding flange 11 of the corresponding upstream or downstream duct 4 or 5 with a fluid tight seal. The mounting flanges 23, and in turn the abutting faces 25 terminate in a peripheral edge 27 which is of square shape and substantially defines a corresponding peripheral edge 28 of the flange 11 of the corresponding duct 4 or 5.By virtue of the fact that each mounting flange 23 is provided with an abutting face 25 which terminates in a square peripheral edge 27 which substantially defines the square peripheral edge 28 of the flange 11, the fan housing 1 can be connected directly to a duct of square shape cross section of similar size without the need for an adaptor duct.

Receiving means comprising a receiving lip 30 extends completely around the peripheral edge 27 of each mounting flange 23 and towards the other of the two mounting flanges 23 for receiving the securing bracket 17.

Each securing bracket 17 comprises a main leg 32 terminating in a flange engaging leg 33 for engaging the flange 11, and a screw carrying leg 34 for carrying a screw 35 for engaging the corresponding mounting flange 23 adjacent the sealing lip 30. Tightening of the screws 35 onto the mounting flange 23 tightly and sealably secures the flange 11 of the ducts 4 and 5 to the corresponding mounting flange 23.

The axial flow fan 3 is an electrically powered fan comprising a fan rotor 37 having a plurality of radially extending fan blades 38 extending therefrom which is driven by an electrically powered motor (not shown). The motor (not shown) is axially aligned with the fan rotor 37, and is housed in a housing 40. The construction of such axially flow fans will be well known to those skilled in the art. Four mounting brackets 42, which are equi-spaced angularly around the fan 3 mount the fan 3 to the fan housing 1. The mounting brackets 42 are secured to the fan housing 40 by screws 43, and are secured to mounting areas 44 of the abutting face 25 of one of the mounting flanges 23.

Screws 45 secure the mounting brackets 42 to the mounting flanges 23. The screws 45 are located intermediate the through bore 22 and adjacent corners 46 of the peripheral edge 27 of the mounting flange 23, and the screws 45 are located on a diagonal extending between opposite corners 46 of the peripheral edge 27.

A cable accommodating opening 48 extending through the mounting flange 23 adjacent one of the mounting brackets 42 accommodates a cable 49 exteriorly of the fan housing 1 for connecting to a power supply for powering the fan 3. The cable 49 is secured to one of the mounting brackets 42.

The diameter of the through bore 22 is just greater than the peripheral diameter of the fan blades 38 to facilitate good throughflow of air under the action of the fan 3 through the through bore 22. Opposite ends 50 of the through bore 22 diverge outwardly for minimizing turbulence in the air flow passing through the through bore 22. The diverging ends 50 are formed by radiusing the respective joints between the inner surface of the through bore 22 and the respective corresponding duct abutting faces 25. By virtue of the fact that both ends 50 of the through bore 22 diverge outwardly, the fan housing 1 is reversible.

In use, with the axial flow fan 3 mounted in the fan housing 1 by the mounting brackets 42, the fan housing 1 is inserted between the upstream duct 4 and downstream duct 5 of the duct run 2. The flanges 11 at the ends 8 of the upstream and downstream ducts 4 and 5 are offered up to the abutting faces 25 of the corresponding mounting flanges 23 and are sealably secured thereto by the securing brackets 17. On all the screws 35 of the respective securing brackets 17 being tightly secured onto the mounting flanges 23 of the fan housing 1, the upstream and downstream ducts 4 and 5, respectively, should be sealably secured to the fan housing 1.

The advantages of the invention are many. One of the main advantages of the invention is that by virtue of the fact that the mounting flanges 23 extending from the central member 20 terminate in peripheral edges 27 which substantially define the flanges 11 of the ducts 4 and 5, the fan housing 1 can be connected directly into a duct run of square cross section without the need for adaptor ducts to be provided between the ends of the fan housing and the adjacent ducts of the duct run. A further advantage of the invention is that by virtue of the construction of the fan housing, and in particular the mounting flanges which include the receiving lips, the fan housing can be readily easily inserted and sealably secured in a duct run.

While the fan housing has been described for accommodating an axial flow fan, it is envisaged that the fan housing may also be used for accommodating a mixed axial and centrifugal flow fan. Indeed, it is also envisaged that the fan housing may be used for accommodating a centrifugal flow fan.

While the mounting flanges have been described as terminating in a square peripheral edge, the mounting flanges may terminate in a peripheral edge of any desired shape which would correspond to the cross sectional shape of the duct to be attached to the fan housing. For example, in certain cases, if the fan housing is to be connected into a duct run of ducts of rectangular cross section, the peripheral edges of the mounting flanges of the fan housing would be of corresponding rectangular shape. It will of course be appreciated that the area defined by the peripheral edges of the mounting flanges will substantially correspond to the peripheral edges defined by the flanges 11 of the ducts of the duct run. It is also envisaged that the two mounting flanges may be provided with peripheral edges of different shape, and/or different area, for example such would be the case if the fan housing was to be connected into a duct run between two ducts of different shape and/or different cross sectional area.

While the fan housing has been described as being of fibreglass material, it will be appreciated that the fan housing may be of other suitable material.

The invention is not limited to the embodiment hereinbefore described which may be varied in construction and detail.

Claims

1. A fan housing for accommodating a fan and for mounting the fan in a duct run between an upstream duct and a downstream duct of the duct run, the ducts being of the type having at least three sides, the housing comprising an elongated central member having a through bore extending therethrough for accommodating the fan and defining a central longitudinal axis, the through bore co-operating with the fan for facilitating the urging of fluid therethrough by the fan, and a pair of axially spaced apart outwardly extending mounting flanges located at respective opposite ends of the central member for connecting the fan housing to the respective upstream and downstream ducts of the duct run, each mounting flange having a duct abutting face extending from and circumferentially around the through bore for engaging the corresponding adjacent duct with a substantially fluid tight seal.

2. A fan housing as claimed in Claim 1 in which each abutting face extends radially relative to the central axis.

3. A fan housing as claimed in Claim 1 or 2 in which each mounting flange extends radially from the central member.

4. A fan housing as claimed in any preceding claim in which each abutting face terminates in a peripheral edge extending circumferentially around the central member, the peripheral edge substantially defining a peripheral edge of a corresponding mounting means on the corresponding duct of the duct run.

5. A fan housing as claimed in Claim 4 in which the peripheral edge of at least one abutting face defines a square.

6. A fan housing as claimed in Claim 4 or 5 in which the peripheral edge of both abutting faces defines a square.

7. A fan housing as claimed in Claim 4 or 5 in which the peripheral edge of at least one abutting face defines a rectangle.

8. A fan housing as claimed in Claim 4 in which the peripheral edge of both abutting faces defines a rectangle.

9. A fan housing as claimed in any preceding claim in which a receiving means is provided on each mounting flange for receiving a securing means for securing the mounting flange to the corresponding duct.

10. A fan housing as claimed in Claim 9 in which each receiving means comprises a receiving lip extending from the corresponding mounting flange adjacent the peripheral edge thereof, the receiving lip being directed towards the other of the two mounting flanges.

11. A fan housing as claimed in Claim 10 in which each receiving lip extends completely around the peripheral edge of its corresponding mounting flange.

12. A fan housing as claimed in any preceding claim in which the through bore diverges outwardly at at least one of its ends for minimizing turbulence in the air flowing therethrough.

13. A fan housing as claimed in Claim 12 in which the through bore diverges outwardly at both of its opposite ends.

14. A fan housing as claimed in Claim 12 or 13 in which each diverging portion of the through bore is formed by radiusing the area where the inner surface of the through bore joins the corresponding duct abutting face.

15. A fan housing as claimed in any preceding claim in which the through bore is of circular transverse cross section, the diameter of the through bore being just greater than the diameter of the fan blades of the fan to be located therein.

16. A fan housing as claimed in any preceding claim in which the central member is an elongated cylindrical member.

17. A fan housing as claimed in any preceding claim in which a mounting area is provided on the abutting face of one of the mounting flanges for engaging a mounting bracket for mounting and locating the fan in the through bore.

18. A fan housing as claimed in any preceding claim in which a cable accommodating opening extends through one of the mounting flanges for accommodating a cable of the fan therethrough.

19. A fan housing as claimed in Claim 18 in which the cable accommodating opening is provided through the abutting face of the mounting flange.

20. A fan housing as claimed in Claim 18 or 19 in which the cable accommodating opening is located in an area of the abutting face adjacent a corner of the peripheral edge thereof.

21. A fan housing as claimed in any preceding claim in which a fan is located in the through bore.

22. A fan housing as claimed in Claim 21 in which a mounting bracket connected to the fan housing and to the fan mounts the fan in the through bore.

23. A fan housing as claimed in Claim 22 in which the mounting bracket is connected to the mounting area of the abutting face of one of the mounting flanges.

24. A fan housing as claimed in Claim 22 or 23 in which at least two mounting brackets are provided, the mounting brackets extending from the fan in diametrically opposite directions.

25. A fan housing as claimed in any of Claims 22 to 24 in which each mounting bracket is connected to the abutting face of the mounting flange at a position intermediate the through bore and a corner of the peripheral edge of the abutting face on a diagonal extending between opposite corners of the peripheral edge of the abutting face.

26. A fan housing as claimed in any of Claims 22 to 25 in which four mounting brackets are provided extending from the fan, the mounting brackets being equi-spaced angularly around the fan.

27. A fan housing as claimed in any of Claims 21 to 26 in which the fan is an electrically powered fan.

28. A fan housing as claimed in any of Claims 21 to 27 in which the fan is driven by an electrically powered motor, the motor and fan being axially aligned.

29. A fan housing as claimed in any of Claims 21 to 28 in which the fan is an axial flow fan.

30. A fan housing as claimed in any of Claims 21 to 28 in which the fan is a mixed axial and centrifugal flow fan.

31. A fan housing as claimed in any of Claims 21 to 28 in which the fan is a centrifugal fan.

32. A fan housing substantially as described herein with reference to and as illustrated in the accompanying drawings.

33. A duct run comprising an upstream duct and a downstream duct, and the fan housing as claimed in any preceding claim mounted between the upstream and downstream ducts.

34. A duct run substantially as described herein with reference to and as illustrated in the accompanying drawings.