US2836350A - Control device for a reciprocating electric fan - Google Patents

Description

y 7, 1958 A. K. TATElSHl- 2,836,350

CONTROL DEVICE FOR A RECIPROCATING ELECTRIC FAN Filed Sept. 21, 1956 3 Sheets-Sheet l 47 L'l/ll H- v I I I INVEVTOR.

ARTHUR K. TATEISHI BY M ATTORNEYS A. K. TATEISHI 3 Sheets-Sheet 2 FIG. 7

INVENTOR.

ARTHUR K. TATEISHI Km M W ATTORNEYS May 27, 1958 CONTROL DEVICE FOR A RECIPROCATING ELECTRIC FAN Filed Sept. 21, 1956 FIG. 5

y 1953 A. K. TATEISHI 2,836,350

CONTROL DEVICE FOR A RECIPROCATING ELECTRIC FAN Filed Sept. 21, 1956 3 Sheets-Sheet 3 MW!! will INVENTORQ ARTHUR- K. TATEISHI ATTORNEY:

United States Patent CONTROL DEVICE FOR A RECIPROCATING ELECTRIC FAN Arthur K. Tateishi, Toronto, Ontario, Canada Application September 21, 1956, Serial No. 611,142

6 Claims. (Cl. 230-459) This invention relates to electric fans of the blower type, more particularly to an electric fan producing an oscillating air flow.

It has been proposed to effect oscillation of the air how by means of reciprocating louvers arranged directly in advance of air impeller blades, but the low eificiency and the serious problems of turbulence have prevented such fans from being commercially acceptable.

The main object of the invention as disclosed in my copending application Ser. No. 440,949 filed July 2, 1954 issued as Patent 2,768,782 is to provide a novel improved and greatly simplified electric fan which will efliciently produce a slowly oscillating air flow by means of re ciprocating louvers without movement of the fan head with a minimum of turbulence and noise. The louvers of the fan are reciprocated by drive means which in turn are driven by the fan motor also rotating the impeller blades of the fan.

T he fan of my copending application also comprises joint control means for controlling the circuit of the fan motor and actuating the drive means, the joint control means ensuring that the load of the louvers is not coupled to the fan motor until the motor has reached adequate speed. This affords the advantage that the louver reciprocation can be obtained with a smaller capacity motor than would be permissible if the louvers could be connected, even accidentally, to load the motor during the starting period which requires an increased starting torque.

The principal object of the present invention is to provide novel and improved regulating means for varying the rate of speed of the oscillations of the louvers without changing the R. P. M. of the motor.

Other and further objects, features and advantages of the invention will be pointed out hereinafter and set forth in the appended claims forming part of the application.

in the accompanying drawing several preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

in the drawings:

Fig. 1 is an isometric front view of a fan according to the invention.

Fig. 2 is a side elevational view.

Fig. 2a is a rear elevational view of the fan.

Fig. 3 is a rear view with a rear part of the fan housing removed to show the fan mechanism.

Fig. 4 is a fragmentary sectional view of the control means of the drive means for the louver assembly of the fan and of the control means for the drive means and the fan motor.

Fig. 5 is a plan view of Fig. 4 partly in section.

Fig. 6 is a view of the components of Fig. 4 turned through 90 and showing the drive means and control means in one operational position.

Fig. 7 is a fragmentary view of Fig. 6 showing the drive means and the control means in another operational position.

C assassin Patented May 2'2, 195? Fig. 8 is a view similar to Fig. 6, but showing speed regulating means for the louvers.

Fig. 9 is a sectional view taken on line 99 of Fig. 8.

Fig. 10 is a fragmentary view of Fig. 8 turned through 90, and

Fig. 11 is a plan view of Fig. 8.

Referring now to the figures in detail, the exemplification of the fan according to the invention comprises a housing 1 forming a wind tunnel. The housing may be 0 made of a light gauge sheet metal, but is preferably made of plastic since the housing proper does not have to carry the weight of the fan mechanism. It is mounted on a base or standard 2 pivotal about a horizontal axis. As seen in the direction of the air flow through the housing, the fan mechanism comprises impeller blades 3, a fan motor 4 and a louver assembly 5.

The housing is composed of two generally ring shaped shells 6 and 7 which complement each other to form the housing. The two shells are closed by grill or wire mesh guards 8 and 9 respectively which serve both, to prevent injury to persons or pets by the whirling fan blades and to protect the fan mechanism against damage. The wire mesh 9 at the front of the fan is preferably reinforced by crossing bars 19 and 11 which may support a name plate 12. The inner wall of the housing is made cylindrical by either giving the inner peripheral wall of shells 6 and 7 a corresponding configuration, or by pro viding, as shown, a cylinder 13 made of thin metal gauge or plastic material and fitted in the housing leaving spaces 13'. The interior of the fan constitutes a wind tunnel through which a straight flow of air relatively free of turbulence is forced by impeller blades 3.

Cylinder 13 also serves to anchor wire mesh 8 within shell 6. To this end, mesh 8 has an extension 8 held between the cylinder and a corresponding wall portion of shell 6. The extension is bent to form a shoulder resting upon shell 6. Wire mesh 9 is anchored by res ing with its rim upon shell 7. This reinforced rim is outwardly slanted to direct and confine the air flow defiected by the louver assembly as will be more fully explained hereinafter.

To obtain maximum efficiency, blades 3 are so mounted that they protrude with about two thirds of the blade area from rear shell 6. Wire mesh 8 also extends correspondingly beyond shell 6 to accommodate the protruding portion of blades 3.

To provide for wide angle air flow oscillation, the shell 7 is formed with its forward side edges recessed or concaved as at 110, as best shown in Fig. 2, which eliminates interference of the housing with the air deflected at a substantial angle to the sides by the louver assembly 5.

The louver assembly comprises several identical louver slats or vanes made of thin sheet metal gauge or plastic, four louver slats 15 being shown. The slats are mounted within shell 7 perpendicular to the fan axis and are arranged to have their forward portions project forwardly beyond the recessed sides 11% of the shell 7. To this end, fiat metal or plastic strips 16 and 17 are secured by any suitable means on diametrically opposite sides of shell 7. These strips constitute mounting bases in which bearings for the louver slats are formed.

The slats are mounted to pivot about their longitudinal centre axis which at the centre of the slat is approximately in line with the recessed sides of shell 7.

The width of the slats is such that the same do not overlap in any pivotal position, or in other words, such that slots for the passage of a straight air flow between adjacent slats remain in each pivotal position of the slats.

To obtain joint reciprocatory pivotal movement of the slats, the same are coupled by joining means more fully a for this purpose.

7 The'drive means 7 motor shaft to the louver assembly for imparting the bya'cotterpin154. V V V h V Wheel 47 is coupled with the louver assembly by} a: bar or wireimeni ber eccentricallysecured atonelend wheel 47 and at its other 'end to the louver -as's embly.

a louver assembly. r a

The fanniotor is shown as a two-pole motor with a generally U-shaped field core 30; The plane base branch of such core permits conveniently to mount thereon the drive means-and the control means of thefan. The drive described in the aforesaid copending applicationt o form V .shaft of the motor which protrudes from both sides of the rotor has its axis lying coincident with the axis of the cylinder 13, ancl inte'rsecting the axis of thepivo t of 'the fanihousing 1 which pivots aboutthe axes of fasported thereon'are mounted in the fan housing by two laterally extendingfbracke'ts. Each bracket is formed by two parallel bars'35 and 36 respectively wln'ch are secured to themotor by any suitable meansfsuch as the U-shaped portions 37; The bars may either be secured to the motor directly or to a plate fastened to the motor The free ends'of bars 35 and respectively are secured to a mounting plate 38 and 39"re-.

spectively.

7 d The motor is connected with a suitable source of current by a connecting cord 105,. To avoid an undue strain onthiscord, the same is preferably meandered by means of guide pins 106, 107 and 198 extending from the inner I wall of shell 7,' as can best be seen in Fig. 3; therebyproviding a strain'relief for the connecting cord.

7 The drivameons for the louver asserizlilyand. the control V 1 1 means. of the fan serve to transmit the rotation of the required 'reciprocat ory' movements to the louverr slats, and the control meansserve to control the motor circuit The drive means comprise a shaft 40 on Which-is seat ed. a large wheel'41 and a small wheel 42 to obtain the required ratio of transmission. Wheel 41 coacts with shaftend 31"by' frictional engagement. To obtain a sat-,

. function as follows: 7

1 Let it be assumed that the 7 means are in'the positions shown in'Figs 4, 5fa ndl6., The switch 60 is then; in its open position disconnecting. the p 4" Wire 55 may be secured to whee'l47 any suitable means. There is shown a headed pin upon which is fitted a closed loop formed at the respective end of wire 55. a

Rotation of Wheel 47 will impart a reciprocatory pivotal movement to all the louver slats. The are performed by the louver slats can be conveniently set by appropriately selecting the eccentricity of headed pin 56, the

length of wire 55 and the associated components relative one to'another. In' practice it has been'found that pivotal movements of the slats through an arc of 45 will give satisfactory results.

The control means further comprise a switch for V controlling the motor circuit mounted on the horizontal branchw ofbracket 45. While this switch may be of any suitable type, a toggle switch as shown is preferred. The

switch has a bifurcated actuating member 61 which coacts with an arm 62 extending from rod 49. This arm.

may be fixedly secured to the rod or as shown beheld by two clamping nuts 63 and 64 to permit axial adjust ment of the arm and to assure rotation thereof in unison withtherod. n

f The drive means and the control means just described,"

drive means and the control motor circuit. Wheel 42 is out of engagement with the wheel 47 and wheel-41 abuts against shaft end 31' only with the"pressure of'its own weight. "When knob 51 is nowIturned through a rather small angle 'in the direction of the arr'ow shown in Fig. 5, arm 62 snaps switch 60 onto its on positionthereby starting the. motor which will turn blades 3 with its full force and speed. Although 7, rod '49 is slightly lowered by the intial rotation of knob 51', wheel 47 remains out of engagement with wheel 42.

During this stage of the operation, wheel 41 maybe V rotated by shaft end 31, or may more or less slip relaand the dr ve means, independently one from the other:

V tween the wheel and the shaft end is only slight. and not capable of transmitting power. This afiords thead vanisfactory power: transmitting frictional engagement between wheel 31 and shaft 31 both,.the wheel and the shaft end are preferably peripheripherally linedwith a 7 high friction material such as a rubber or a rubbercomposition. Shaftis supported byan arm 43'pivoted at 44'to a right angle bracket 45; This bracket is se- 7 cured to the motor as can b est be seen in Figs. 4 and 6.

' The perpendicular part of the bracket (as shown in Figs.

4 and 6)' is formed with a cut-out 46 to permit a free up and down movement of the end of arm 45 supporting shaft '40; As a 'result, wheel 41 constitutes a floater wheel which is 'in' power transmitting frictional engagement with shaft end '31" only whenpressed against the a shaft end. a a V I The small wheel 42 coacts with a horizontally mount ed; wheel 47 by frictionallyfingnging the peripheral rim 7 of wheel 47 when the two wheels are mo'ved toward each other. Wheel 47'is'rotatahly mounted on a rod j49'by any suitable means such asa bushing 48 Rod 49 has a threaded portion 49 which is screwed'in a-bracke1t-50' fixedly' -secured to the horizontal branch of bracket 45., 7 As is'apparent, rotation of rod 49 l i Q 7. f n a i e ,brm of a knurledor'jmilled controlled knob 51res ultsljn an .axial' up and down movement of rod;49fa.nd hence of wheel%f47; JA- loaded sinngfsz abutting 'aton'e "end;

' a g'ainst a shoulderof rod 49 a washer 53vai1d at the other end against bushing edserves to bias wheel 47iinto l its lowermost position on rod-49' in which ijtjisretained tive thereto dependingupon the friction between the" wheel and shaft end. In any event the engagement betage'that'the wear and tear upon the peripheralsurfaces of wheel 41 and shaft end 31 are negligible when the blades'only of the fan are operated.

.It will .be understood that while rod the spring 52 to engage 'the wheel 42 'with' the correct pressure for drive of the wheel 47 without requiring criti cal control of the movement of rod Furthermore 'i this'spring 52 will automatically compensate for anywear;

in rubber or metal parts. 1 This control arrangement ensures that the load c011 of the rubber parts; r 7

5 When it'is desired to start the louver assembly, rotation of knob 51- is continued until wheel 47 cngages wheel 42 with a pressure" sulficient to force the floating wheell41 a into power transmitting engagement with shaft end-31; "1

Asa resultpthe rotation of'theshaft end is transmitted to; wheel f47; which rotates about rod '49 and imparts Q through" eccentric pin 56 and wire 55 the aforedescribcd pivotal movements toallthe louver slats. i i

opposite rotation of knob '51'ifirst moves wheel 47 w is positively; advanced ,by screw or cam action, the wheel47 isQfree to travel axially of the'rod and is biased under action of t n." blades; knob SL is rotatediin oppositedirection. Such of engagement with wheel 42 and then switch 60 into its ofi position. As appears from the previous description, a single common control means permits selectively to operate either the fan blades only or the fan blades and the louver assembly jointly, operation of the fan blades only producing an air flow in a fixed direction and operation of the louver assembly an oscillation of the air flow by the effect of the reciprocating louver slats.

Standard of the fan The standard comprises a base plate 70 from which extends two pairs of bent arms 71, 72 and 73, 74 respectively, the opposing pairs of arm portions 73 and 74 being spring urged inwardly to grip the housing 1 therebetween. These arms are joined at their free ends by caps 75 which form a base for fastening means enabling the shells of the housing and the components supported therein to be fastened by a single operation. The fastening means also serve as a horizontal axle about which the entire fan assembly may be tilted.

The drive means and the control means according to Figs. 4 through 7 correspond to those disclosed in the aforesaid patent 2,768,782. They impart to the louvers a fixed angle of reciprocation and have been included in this application to facilitate the understanding of the present invention. As stated before, the principal object of the present invention is to provide means for varying the reciprocatory speed of the louvers while maintaining constant the angle of reciprocation and the rotation speed of the motor.

As is apparent from the previous description, the movements of the louvers are controlled by the rotational speed of wheel 47 which in turn is controlled by the ratio of transmission between the shaft of the motor and wheel 47. The speed adjustment of Figs. 8 to 11 provides for a variation of this ratio by varying the radial distance at which drive wheel 42 engages driven wheel 47.

To this end wheel 41 is secured to a sleeve 125 to which is also secured drive wheel 42. Sleeve 125 is axially slidable on a shaft 40. To permit an axial displacement of the sleeve and with it of wheel 41, the shouldered part 31" of the motor shaft is correspondingly extended. As is apparent, axial displacement of sleeve 125 will correspondingly vary the rotational speed of driven wheel 47 for a given constant rotational speed of the motor.

To effect axial displacement of the sleeve, 3. grooved collar 126 is secured to the sleeve and engaged by an actuating means generally designated by 127.

The actuating means is shown as comprising a member of generally U-shaped configuration. The member is rotatably seated with its branches 128 and 129 on rod 49 and bracket 50 respectively so that it can participate in the slight up and down movement of rod 49 when the latter is rotated for controlling the motor drive as previously described. To provide the necessary space, bracket of Figs. 4 through 7 has been modified to comprise a part 45 similar to the previously described bracket, for mounting shaft 40 and a raised horizontal tongue 45" mounting switch 60. The lower horizontal bracket 129 of the U-rnember extends between the horizontal part of bracket 45 and tongue 45" as can best be seen in Fig. 8. This figure also shows that the rotation of switch rod 62 and the actuating means 127 do not interfere one with the other.

Rotation of the U-shaped member is transmitted to collar 126 by means of a toothed section 130 on branch 129 and a rack 131 from which extends a slanted arm 132 ending in a bifurcated portion 132 straddling collar 126. Rack 131 is slidable on bracket part 45' parallel to the rotational axis of wheel 41 and is provided for this purpose with two elongated slots 131 engaged by pins 133.

Rotation of the U-shaped member about the axis of rod 49 effects axial displacement of sleeve 125 and the parts associated therewith in one direction or the other. To facilitate setting of the adjustment means, an arm 6 134 endingin a finger grip 135 extends from the upper bracket 128 of the U-shaped member. This arm is situated outside of housing 1, preferably adjacent to knob 51. Fig. 11 indicates the required angular movement for causing faster or slower oscillations or reciprocations of the louvers.

To prevent rattling of the assembly and to detain the speed adjustment at definite settings, detents 136 are preferably provided on rack 131. These detents coact with a soft spring 137.

As is evid nt from the previous description, the illustrated speed adjustment means can be altered in various respects without departing from the scope of the invention.

What is claimed is:

l. A control device for controlling the operation of an electric fan of the kind including impeller blades rotatably mounted on the intake side of the wind tunnel for producing an airflow therethrough, a louver assembly including several parallel louver slats disposed at the delivery side of the tunnel, motor means drivingly connected with said blades for rotating the same; driving means for drivingly connecting said motor means with said louver assembly to impart to the slats thereof a reciprocatory movement through a predetermined constant angle, said drive means including an input wheel frictionally engageable with the drive shaft of said motor means, an intermediate wheel mounted for rotation in unison with the input wheel, an output wheel frictionally engageable with said intermediate wheel, coupling connecting said output wheel with said louver means for imparting said reciprocatory movement to the louver slats upon rotation of said output wheel, and control means for moving the said wheels into and out of rotation transmitting frictional engagement with each other and said motor drive shaft for coupling the motor means with the louver means, said control means comprising a regulating means included in said drive means, said regulating means including means for axially displacing said intermediate wheel to vary the radial distance between the point of engagement of the intermediate wheel with the output wheel and the rotational axis of the output Wheel for regulating the ratio of transmission between the rotational speed of the motor means and the speed of the reciprocatory movement of the louver assembly, thereby regulating the rate of speed of the reciprocatory movements of the louver slats while maintaining constant the rotational speed of the motor means and the angle of the slat movements.

2. A control device according to claim 1, wherein said input wheel and said intermediate wheel are seated on a common shaft which is supported displaceable paraliel to the drive shaft of the motor means, and said output wheel is seated on a shaft disposed perpendicular of the aforesaid shafts and axially displaceable by said control means whereby displacement of the output wheel shaft in the respective direction moves the output wheel into frictional pressure engagement with the intermediate wheel and the input wheel into frictional pressure engagement with the motor drive shaft, said intermediate wheel being axially displaceable on said common shaft to vary said point of engagement.

3. A control device according to claim 2, wherein a sleeve axially slidable on said common shaft mounts said intermediate Wheel, and wherein a linkage means is operatively connected with said sleeve for axially displacing the same, said linkage means including an actuating member protruding from said wind tunnel for actuating the regulating means from the outside of the wind tunnel.

4. A control device according to claim 3, wherein said linkage means include a rack and toothed sector link for converting a rotary movement of the actuating member into the linear movement of the sleeve.

5'. A controhdeyice accoriiing to claim 4, wherein said linkage means further included-a link pivotal about the shaft of the output wheel, said pivotal link mounting said 'toothed sector and said actuaging member.

6. A control deviee according to claim 5, wherein said linkage means also include detent means for yieldably arrestingrsaid actuating. member in a selected one of several piedetermined positions, a

Tateishi Oct. 30,

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