US1820448A - Fan blade - Google Patents

Description

Aug. 254, 1931. LN, DAVY 1,820,448

FAN BLADE Filed Jan. 13, 1930 2 Sheets-Sheet 1 L. N. DAVY Aug. 25, 1931.

FAN BLADE Filed Jan. 13, 1930 2 Shuts-Sheet 2 [/yzzciez 4 4547 ATTO RN EYl-s' Patented Aug, 25, 1 931 .xLYNDEfi'N', saw, or BUTTE, MONTANe .i

. l f as irate; luminary 1a ,'19so.]js riaiinf-126,465,];j lv i v tially normal to the axisfof. rotation and" ordinary use of electric fans,theoperation Thisinventionrelates to'iinprovements in of the fan blades and the firwardfxtririity electricfansTo-f.the type iordi narily used of the drive'shaft. "in producing, a circulation of air for 'cool- Figure 4 is'a rearele'v'ation ofthefan dug and] ventilating ro'qms in residences, blade assembly, and 5-: llfofiices and other dwellingsl i l Figures 5, 6, 7 and Sare detail cross sec- {'55 [One of the objects ofithis invention isthe tions takeni res'p'ectively on theflin'es 5 5, "provision of an electric fan that will direct 6-6, 7+7 and'8 8 of Figure/1. 1 air currentsthrough Substantially the en- Referring now to thejdra'wings,;the'numi tire semi-spherical space in front of and eral 9' designates the base of. a portable elec- 9 around the fan blades. r J I Another object offthisflinvention is the tor 11, the bracket 10 being adjustably arrangement ofthe fan blades whereby only mounted upon the b'ase9 and secured inany ,7 a, relatively gentle breezeis thrown'dlrectly desired angular {position vby means of the forward from thefanfand the remainder bolt 12 and wing nut13.. It'is 'to'be, under tric fan and -10a 'bracket carrying theme: 60

" 501? the. air currents delivered from the fan "stood that the illustrated embodiment offt'he we blades in radially outward and on outwa'rdsupportvf or theimo'tor ean blade assem-, ".ly divergent paths, whereby 'theobjectionbly is merely for'p urp'osesgof ,exeinplificafable strong. draft ordinarily created bytheftion, and that any desired meansof 'supportusual electric fanui's obviated and a-person ing the fan bladeassembly formingfl'the i my remain directly in'front oflthe fan withclaimed disclosure hereinf'may; be employed; 79 V out inconvenience or detrimental efiectsl l he' adjustability of,-the j support, substan-' i A ifurther object of. this invention is the ,tially as herein shown, however,emphasizes k I provision of an electric fan having blades "theiadaptabilit'y of the fanblade assembly to each provided with alrear portion substansubstantially all. conditions arisingthe a front 'p ortion having a comparativelyjwide of the fanyblade assembly being substam V extremit adj acent'the shaft arranged at an tially the samewhethe'r the 5 revolving'motor angle o greater than ninety degrees to shaft is in horizontal, vertical, or in various the rear'portion, and then as it extends from 'angular positions. l

7 its inner end to its outer end, has a'substan-- The motor 11 may of desired ty p'ie j"3 I tially uniformtwist to. less than aninetydefor operation by an desired formof current, gree" angle to the 'rear'portion, while also and forwardly extendingtherefronif isthe diminishing in width from itsinner to its stub shaft 11 upon which is suitablylmountouter extremity. l, V V I V 1 edthe sleeve 14 carrying the'spider 15' form- Other'objects and advantages will be ap- "ing the central portion of thefan bladeas 1' parent from; the following description sembly, the sleeve 14 being suitably fastened 7 To 'wherein'refe'rence is made to the accompanyupon the stub shaft 11 as by means'of, the I ting-drawings showing a preferred embodiset screw '16; 5 The spider; 15 is arranged ment, of my invention, and wherein similar with its center portioniniali'gnment with thew; "reference numerals designate similar parts axis of the motor shaft and is provided with??? throughouttheseveralview's.i v a plurality of radiallyextendingarnisffor In thedrawingsrf 7 I the receptionof'the fan blades"? l Obvi'ously, Figure l'is I'af side elevation-of my imany desirednumberof spidenarfnsf l iy proved 'electric fanwith' a portion of the employed, according to the intended use of] protecting cage broken away. f f the fan and the desirednurnber ofblad'e'sf' Figure 2 is a." front elevation thereof, 'Securedto each arm ofthe'spidrlais a v withalmost an of theflprotecting cageomitfan blade 17 preferably constructed substan ted to disclose the construction of the'fan' tially as herein shown'and comprisingarear bladesf 1 0 j I portionli of'substantially triangular shape; H Figure 3-is an enlarged perspective =viewfand arranged as a radial ezztension' of'the spider arm, and a forwardly extending portlon 17 integrally formed with rear portions 17*. As best shown in Figures 2-4, the rear portion 17 of each fan blade is arranged substantially as a right angled triangle with its base secured in proximity to the motor shaft 11 d. its straight si e arran ed as a substantial extension of one side of t e spider arm to which it is secured. The front portion 17 of each fan blade extends along the hypotenuseof the triangular rear portion 17 and is shaped to provide for the desired dissemination of the air currents throughout the entire semi-spherical space. in front of and around the fan blades. To this end the nn r extremity of. the front portion 17 b of each fan blade is formed with a omparatively Wide porti n arra ged at a greater than ninety degree angle to the rear ortion 17" of the blade, and. then as the rout portion extends toward its outer extremity it has a substantially uniform twist whilev also diminishing in width. The twist of the fron po ti n of the blade xt fromv a greater than ninety degree angle to the rear portion at its, inner end to a less than, ninety degree angle to the rear, portion adjacent its outer end, and the outer end of the blade is preferably about one v half of the width ofthe, inner end of the front portion 17". The extra width of the front portion, 17 of each blade adjacent the center of the fan is important in preventing thefe rnat n of a va uu d re y in ront of thefan, and the twist of the forwardly,

extend g portion 17 of the fan blades determines the proportions of air currents dis- S minated in a or ard direction, radial directions and through intermediate directions. r outer extremities of the blades throw the air currents substantially outward and, then as. the twist in the front portion 1'1 of each blade extends beyond the normal to therear portion 17 of the blade the air CM QLItS directed thereby extend forwardly and outward y throug angl s int rmedia Such radial, direction and the axis, of the revolving motor shaft. In addition to twistthe, forward portion l?- of each blade attends obliquely across the straight side of the rear portion 17 of the blade (note Fi tir s 2 and v The blades, when mounted for operation, are usually confined by a wire protecting. Cage 0f the usual or any desired const uetion. a r

In operation the air to be set in motion by the otat ng; inn b e sis dr wn over and ar u d he Di ter a th rear f the; fan blade. as em y nd is thrown or rd y, a ia y, and obl qu ly f rwardly and utay h, the various. portions of the fan blad s, vzlie I tionv throughout subs ntial y t e e tire semi-spherical space in front of the fan.

r latively gentle breeze effect directl in i'rontofthe fan, whereby a person may remain directly in front of the fan Without being inconvenienced by the usual strong .draftiemanating: from the ordinary electric fans. The distribution of the air currents ever a wide area also serves to quickly stir up the air throughout a room, facilitating ventilating and cooling of the room.

It will also be noted that the desired effect of reating air currents throughout the entire semi-s herical space in front of the fan is secured y a simple and comparatively inexpensive arrangement Of the fan blades; which are, mounted upon the motor shaft in substantially the same manner as the blades ofthe ordinary electric fan as distinguished from the substantially s herical or semispherical types of revolving flowers; and the like that are used primarily for wivithdr awing air andgases from factories and other buildings,

\Vhile it is apparent that the, illustrated embodiment of my invention herein dis closed is well calculated to adequately fulfill the objects and advantages primarily stated, it is to be understood that the invention is susceptible to, variation, modification and chang Within the spirit and scope of the; 1

snbioined claims, 7

, I claim: j i

An impeller having a plurality of blades each provided with a rear portion arrangedsubstantially normal to. the axis of rotation of th fan blades and a front, portion having an inner extremity arranged at a greater than ninety degree angle to said rear portion and having an outer extremity arranged at a less than ninety degree angle to said rear portion, the front portion intermediate its extremities having a substantially uniform twist.

2. An impeller having a plurality of blades each provided with rear portion: arranged substantially normal to the axis of rotation of the fan blades. and a front portion having an inner extremity arranged at a greater than ninety degree angle to said rearportion and having an outer eX-' tremity arranged at a lessthan ninety degree angle to said rear portion, the front portionintermediate its extremities having a substantially uniform twist and the inner extremity of the front portion being comparatively wide. and the outer extremity thereof comparatively narrow. rehy air curren s are t. in mei 3. An impeller having a plurality of blades each provided with a substantially triangular rear portion arranged substantially normal to theaxis of rotation of the' fan blades and a front portion having an 3 inner extremity arranged at a greater than ninety degree angle to said rear portion and having an outer extremity arranged at a less than ninety degree angle to said portion, the front portion intermediate its extremities having a substantially uniform twist and'extending along the hypotenuse of the rear portion. 4. An impeller blades each provided with a substantially triangular rear portion arranged substana tially normal to the axis of rotation of the fan blades, and a front portion having a comparatively wide inner extremity ar-z' ranged at an obtuse angle to'said rear por-' tion' and a comparatively narrow outer extremity arranged at an acute angle to said rear portion, thelfront portion intermediate its extremities having a substantially uniform twist and reduction in width.

5. An impeller having a plurality of blades each provided with a substantially triangular rear portion arranged substan-' tially normal to the axis of rotation ofthe fan blades, and a front portion having a comparatively wide inner extremity arranged at an obtuse angle to said rear portionand I having a comparatively narrow outer extremity arranged at an acuteangle to said I rear portion, the front portion extending 1 along the hypotenuse of the rear portion and having a substantially uniform twist and o reduction in width from its inner to its outer v extremity. J q i 6. A tan. blade assemblycomprising a I central spider and a plurality of blades secured upon the spider each blade including a substantially triangular rear'portion ar} ranged substantially parallel to the spider and a 7 front portion extending obliquely along the hypotenuse of the rear portion and having spaced portions arranged respectively at obtuse and acute angles to the rear portion.

In testimony whereof I sign this specification.

LYNDEN N. DAVY- having a plurality of-

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