US1919250A - Propeller wheel for fans - Google Patents

Description

July 25, 1933. A. H. oLsoN PROPELLER WHEEL FOR FANS Filed Nov. 6. 1931 @IWM Patented July 25, 1933 UNITED STATES PATENT OFFICE;

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The invention relates to propeller wheels for fans.

It isv now common practice to provide sta- .tionary deflectors in front of the propeller U wheels of ventilating fans to deflect the air projected axiall by-the fan obliquely outward to spread t e air over a wide area- The pnmaryobject of the inventionis to front of the center. of the fan. The front edge'15 and the rear edge 15 of member 15 are helical or curved or slo 'd rearwardly with respect to a diametric line.

may for descri tive purposes be regarded as connecting wit the member 15 on the line 181 8 of Fig. 3, is tan ntial. or inclined to I The front .face of the intermediate member17, which propeller wheel for fans which will operate the plane of rotation of t wheel, and its ont er portion is curved .rearwardly axially to provide a surface which will propel the air obliquel frontwardl and outwardly in gradual increasing e ee from the axis of the whee The front edge 17 and the back edge 17 b of the intermediate member 17 are provide a pro ller wheel which is provided with blades w 'ch will efliciently spread the air over a widely flared zone to distribute it over a large portion of the room, so that separate deflectors for this urpose can be dispensed with. Another ject is to provide a 35 of sheet metal.

efliciently. Other objects will appear from the description. I

The invention consists in the several novel features hereinafter set forth and more par- 573 ticularly defined by claims at the conclusion hereof.

In the drawing: Fig. 1 is a front elevation of a fan embodying the invention. Fig. 2 is a side elevation. Fig. 3 is a. front view of 25 one of the propeller blades. Fig. 4 is a rear end view of one of the blades. Fig. 5 is a plan of one of the blades. Fi 6 is a section on the line 6-6 of Fig. 3. tion on the line 7-7 of 3.

The invention is exemp ed in a propeller wheel secured to the shaft 10 of an electric motor 11 which may be of any suitable construction. The wheel comprises a series of ig. 7 is a secfour blades 14 which are preferabl formed its face is inclined transversely to the plane of rotation as shown in Fig. 7, to propel the air forwardly of the wheel while the latter is rotated. The front face of member 15 is also inclined frontwardl as shown in Fig. 6,

to propel the air slight y toward the center ofthefanandprdventadea'd-airspacein gressively in the rotation of the wheel.

may or descri tive purposes be re also helical or curved backwardly relatively to a diametric line and in the plane of-rotationto cause the blade to act on the air gr}? air tends to slide radially outward and backwardly over the front face of the inner portion of the member 17, and this formation causes the air to be effectively ropelled obliquely forward. The tip mem r 16, wlich rde as merging with t e intermediate portion on the 'line 19-19 of Fig. 5, is extended totrail the member 17 in the rotation of the wheel, is curved longitudinally of the axis and the same as the outer end of the member 17. The tip is tangential to render it efiective in re pelling the air outwardly from the axis of the wheel. Its edges 16 and 16 terminate in a int-16. I The tip constitutes a sweep-back ormation to act suvely on the air which has a tendency to slide over thefront face of the blade.

In operation the inner members 15, by reason oftheir transverseinclination and their frontward and outward inclination propel air frontwardly and sufieiently towards the axis to prevent the formation of a dead-air s ace in the central zone in front'o'f the wheel.

e intermediate members 17, b reason of being tangential and their meg rearward slo propel-the air obliquely fmntwardly an outwardly from the axis pvely increasing degrees to distribute the air through a wide conoidal zone. .By reason of e sweep-back of the portion, the air slipping along their faces will be effectively propelled by these members. The tips which trial and intermediate ortions in the rotation of the blades render them more effective in propelling the air in the outer portion of the conoidal zone of air propelled by the wheel and prevent the formation of eddy currents which would lessen the efiiciency of the intermediate members of the blades. The wheel in its entirety propels a substantially conoidal 90 zone of air as indicatedin Fig. 2', with substantially uniform pressure throughout the entire zone and thus effects the desired wide distribution of the air under moderate pressure over a wide area in a room.

The invention exemplifies an air propeller- Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. As a new article of manufacture, a wheel for propelling air comprising a hub adapted for connection to a drive shaft, and a plurality of blades connected to and projecting outwardly from the hub, each of said blades consisting of an outwardly flared, transversely inclined inner part extending outwardly from the hub and having the leading and trailing edges thereof curved rearwardly with respect to the direction of rotation of the wheel in a substantially spiral manner, an intermediate part extending outwardly and backwardly from the outer portion of the inner part and rearwardly with respect to the direction of rotation of the wheel and shaped so as to propel another portion of the propelled air forwardly and outwardly in' gradually increasing degree vfrom the axis of rotation, and a tapered tip extending backwardly from the rearmost portion of the intermediate part substantially longitudinally withrespect to the axis of rotation of the wheel constituting a sweep-back formation whereby the air sliding off the rearmost part of the intermediate part is Ideflected outwardly during rotation of the v; ee

2. As a new article of manufacture, a. wheel for propelling air comprising a hub adapted for connection to a drive shaft, and a plurality of'blades connected to and projecting outwardly from the hub, each of said blades consisting of an outwardly flared, transversely inclined inner part extending outwardly and slightly forwardly from the hub so as to defi eat a portion of the propelled air inwardly towards the axis of rotation and prevent the formation of a dead-air space in front of the center of the wheel and having the leading and trailing edges thereof curved rearwardly with respect to the direction of rotation of the wheel in a substantially spiral manner, an intcrmedi ate part extending outwardly and backwardly from the outer portion of the inner part and rearwardly with respect to the direction of rotation of the wheel and shaped so as to propel another portion of the propelled air forwardly and outwardly in. gradually increasing degree from the axis of rotation, and a tapered tip extending backwardly from the rearmost portion of the intermediate part substantially longitudinally .with respect to the axis of rotation of the wheel constituting a sweep-back formation whereby the air sliding off the rearmost part of the intermediate part is deflected outwardly during rotation of the wheel.

ALExH. OLSON,

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