AU593056B2 - Axial flow air humidifier - Google Patents

Description

pp.

:21 593056 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952-62 COMPLETE

SPECIFICATIOI

(ORIGINAL)

FOR OFFICE USE: Application Number: Lodged: 2 8 1/ 7 Class Int. Class CmpI Specification Lodged:I Complete Specification Lodged: Priority- Relatod Art: Accepted: Published,--' ^,yf-wt v i 4g.

p~ g I Mfd LCb3DAT SuS.OF1C 1 37 aE 1987 Adelaidej PEE STAyP TO VALUE OF

ATTACHED

MAIL 0FFICE/ i~f t. Class Name of Applicant: Address of Applicant: Actual Inventor: Address for Service: TO BE COMPLETED BY APPLICANT F F SEELEY NOMINEES PTY LTD 3 Rothesay Avenue, St Marys, State of South Australia, Commonwealth of Australia PETER SYDNEY

WRIGHT

C/o R K MADDERN

ASSOCIATES

345 King William Street Adelaide, South Australia 5000 Complete Specification for the Invention entitled: "AXIAL FLOW AIR HUMIDIFIER" nThe following statement Is a full description of this invention, Including the best method of performing it known to rne us: -2- Air humidifiers (evaporative air coolers) are produced in a number of configurations and included in those configurations there is a well known shape wherein a cylindrical wall of absorptive material (for example woodwool) surmounts an annular tank or sump, and an axial flow fan is carried by a motor centrally of the cylindrical wall and is caused to draw air through the absorptive material and discharge it through the central annulus of the sump or tank. This arrangemen- has some advantages over alternative arrangements, one of the advantages being that the cost is low and another advantage being that the unit can be made very compact.

This invention is directed to the above-defined type of air humidifier (although not necessarily annular), and has for its main object the provision of still further simplicity, the consequential advantages related to cost and maintenance.

In this invention an axial flow air humidifier comprises a base tank, an outer upstanding wall defining the outer perimeter of the base tank, an absorptive pad carried by said outer wall, an inner upstanding wall defining an inner perimeter of the base tank and also an air discharge opening, a Ct ~central well containing a pump impeller, a plurality of conduit Sribs radiating outwardly from the central well and placing the central well into fluid flow communication with the base tank, a tube extending from the central well and arranged to deliver water when pumped by the impeller to be discharged over the absorptive pad, a shroud extending upwardly from said base tank inner peripheral wall, a motor contained within the shroud, and a fan, the motor having a depending shaft coupled for drive to the impeller, and an upwardly extending shaft coupled for drive to the fan.

An embodiment of the invention is described hereunder in some detail with reference to, and is illustrated in, the accompanying drawings, in which '~'i3 0

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FIG. 1 is a perspective view of a rectilinear air humidifier, FIG. 2 is a fragmentary central section thereof, FIG. 3 is a local section taken on line 3-3 of FIG. 2, FIG. 4 is a local section taken on line 4-4 of FIG. 2, and FIG. 5 is a plan view of the shroud.

In this embodiment, an air humidifer 10 has an upper wall 11, a tank 12 at its lower end, and four side walls 13 of grill-like formation each containing a wood-wool pad Each side wall 13 is arranged to support its woodwool pad or pads arranged above the periphery 16 of the tank, which is provided with a deflector flange 17 to deflect the flow of water from the pad back into the tank.

An inner side wall forms part of a shroud 20, the upper end 21 of which is flared so that air from the wood wool pads 14 can flow into the annular space 22 which is swept by fan blades 23 with a minimum of turbulence.

There is provided a plurality of channel section ribs 25 which function as conduit ribs and radiate outwardly from a central well 26 and are monolithic.with f 25 inner upstanding side wall 27 of the tank 12. Each channel rib 25 is of U-shape, having a base 28 and two side walls 29 (FIG.3), and its upper edge is approxi- i! mately at the same level as the upper edge of the tank 12. Each of the channel ribs 25 communicates with the liquid containing space of the tank, while at its radially inner end it communicates with the well 26. The iV'>d 4 A& inner wall 27 of the tank 12 is circular in plan, and 1- defines an air discharge opening below the shroud -4- The cup-shaped well 26 is provided with a pump impeller 31 arranged to draw water from the well 26 and impel it by centrifugal force through a discharge nipple 32 and into a tube 33, the water being transferred by the tube (shown by chain-dot lines in FIG. 2) to the upper edges of the woodwool pads 14 to discharge downwardly through the pads and thereby moisten the pads, surplus water flowing back into the tank 12 as described above.

The shroud 20 also has radiating ribs 34 which overlie the conduit ribs 25, and a central boss 35 overlies the well 26 (FIG.5). The ribs 34 are shaped as shown in FIG. 3 to provide minimum obstruction to airflow. The o* 0 boss 35 has motor support pads 37 which support a motor .o 38 having a downwardly projecting output shaft 39 and an S15 upwardly projecting output shaft 40. As said, the downo o wardly projecting output shaft 39 carries the pump impeller but the upwardly extending shaft carries on it a 0 osleeve 41 which depends from the interior or concave r surface of a central partly spherical boss 42 which has apertures 43 in the compound curved surface thereof, the apertures thereby being in a low pressure zone externally but the boss is downwardly opened so that the interior 44 of the boss is a high pressure zone, the pressure i differential being effected firstly by the air flow over the compound curved surface of the boss and secondly by the pressure imparted by the fan blades, and causing a flow of cooling air over the motor 38.

The shroud 20 overlies the conduit ribs 25 and the well 26, as said above. In order to achieve an accurate location, the radiating ribs 34 of the shroud 20 have depending plates 46 which enter the shaped conduit ribs 25 of the tank and well combination (FIG. and lugs 47 (FIG. 5) secure the shroud to the tank 12 by securing means (not shown).

Although the fan blades 23 can be arranged to be readily adjustable, in this embodiment they are monolithic with the boss 42, and extend outwardly into the shroud space 22, and their rotation achieves a high degree of efficiency.

The tank is provided with mounting means (not shown) whereby the entire humidifier can be mounted, and the upper end of the woodwool pad is closed or at least partly closed by the upper wall 11.

The fan housing or shroud may, and desirably is limited to a circular shape, and in some embodiments the tank can also be of an annular shape. The fan housing may blend into a square duct which depends from a square opening in the base of the tank if this is preferred.

Alternatively a duct adaptor may be used to blend from the circular shroud to the square or rectangular duct.

A consideration of the above embodiment will indicate the invention to be extremely simple but nevertheless provides a number of advantages over the prior art. Firstly, the fan can be set low, and the fan blades may rotate quite close to the water surface without imparting turbulence such as to disturb that I surface. The water surface of course is limited to the channel rib or ribs. Secondly, the cooling of the motor is effective because of the "reverse flow" from the high pressure to the low pressure zones below and above the fan blades. Thirdly, the construction is so simple that the cost is very low. Still further, the construction can also be made so simple that replacement of the pad, fan or repairs to the motor can be very simply and easily i effected.

Claims (9)

1. An axial flow air humidifier having a base tank, an outer upstanding wall defining the outer perimeter of the base tank, an absorptive pad carried by said outer wall, an inner upstanding wall defining an inner perimeter of the base tank and also an air discharge opening, a central well containing a pump impeller, a plurality of conduit ribs radiating outwardly from the central well and placing the central well into fluid flow communication with the base tank, a tube extending from the central well and arranged to deliver water when pumped by the impeller to be discharged over the absorptive pad, a shroud extending upwardly from said base tank inner peripheral wall, a motor contained within the.shroud, and a fan, the motor having a depending shaft coupled for drive to the impeller, and an upwardly extending shaft coupled for drive to the fan.

2. An axial flow humidifier according to claim 1 wherein said conduit ribs are channel shape.

3. An axial flow humidifier according to claim 1 or claim 2 wherein said shroud has a circular side wall, and a plurality of radiating ribs near its lower end, which overlie respective said conduit ribs. It

4. An axial flow humidifier according to claim 3 wherein said shroud comprises a central boss near its lower end which overlies said well, and is joined by said radiating ribs to said shroud side wall. j j5. An axial flow humidifier according to claim 4 wherein said central boss has motor support means which support said motor to be coaxial with said shroud side wall, and lies entirely within said side wall.

A C VY -7-

6. An axial flow humidifier according to any one of claims 3 to 5 further comprising an annular boss of part spherical shape having a coaxial sleeve depending from an inner upper surface thereof, said sleeve firmly engaging the upwardly extending motor shaft, said fan comprising a plurality of fan blades which extend outwardly from the annular boss into a space defined by the shroud side wall.

7. An axial flow humidifier according to any one of claims 3 to 6 wherein the upper end of the shroud has an outwardly flared shape.

8. An axial flow humidifier according to any one of claims 3 to 7 wherein said shroud ribs comprise plates which depend into said conduit ribs and thereby locate the shroud with respect to the tank.

9. An axial flow humidifier substantially as herein described with reference to and as illustrated in the accompanying drawings. DATED this 3rd day of FEBRUARY, 1987. F F SEELEY NOMINEES PTY LTD By its Patent Attorneys R K MADDERN ASSOCIATESi