US1295618A - Fan-machine. - Google Patents

Description

E. T. SHAW, FAN MACHINE.

APPLICATION FILED SEPT. 10, I914.

1 95,610 Patented P610125, 1919.

2 SHEETS-SHEET I.

With eases-r I Inventor-1 E. T. SHAW.

FAN MACHINE.

APPLICATION FILED SEPT. 10. 1914.

1 ,295 619 Patented Feb. 2-5, 1919.

' '2 SHEETS-$HEET 2.

Fig. 6. .37

13 s E '1. SW, OF PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPOTION' OF NEW YORK.

1,295,64l&

Specification of Letters Patent. Patented Feb. 25, 1919,

Application filed September 10, 1914. Serial No. 861,120.

1 b all whom it may concern Be it known that I, EDWARD citizen of the United States, resldmg at Pittsfield, county of Berkshire, State of Massachusetts, have invented certain new and useful Improvements in Fan-Machines, of which the following is a specificatlon.

My invention relates to a fan machine in which one or more rotary fans are mounted upon a revolving structure or carrier, and it is concerned more especially with. a propulsive action of the rotary fan to revolve the carrier. It is my aim to control and regulate the rate of revolution of the carrier effectively: to secure rapid starting and speeding up thereof to its desired normal speed when the fan is started up or brought into action upon the air; and to provide for convenient variation of the normal speed by way of adjustment. Other advantages obtainable in connection with my invention include efficiency, simplicity, reliability, and convenience in action and operation; thorough and controllable distribution of the air acted on; and comparative simplicity, durability. and ruggedness of construction. The principles and character of the invention will appear from the following discussion and from the subsequent description of particular embodiments, while its scope is indicated in my claims.

In accordance with my invention, 1 control and regulate the speed of the revolving carrier by varying or regulating the propulsive effect or torque produced upon it by the rotary fan. As the speed of revolution ordi: narily desired for the carrier is compara-, tively low and the inertia and static friction of the revolving parts usually considerable, it is often impossible to start the carrier into revolution from a state of rest without an effective torque so high that it would ultimately produce a speed far greater than is desirable. Bv my invention it is practicable to employ a higher torque for starting than is necessary to maintain the normal speed when once attained or even to start succesfully,so high, in fact, that the period required to bring the parts into revolution and up to speed from a state of rest isverv short indeed,-and also to regulate and adiust the carrier speed for normal running with great delicacy. I secure both the quick starting and the regulation of the speed of the carrier for normal running automatically, by pro- T. SHAw, a

viding means for suitably varying the torque controlled by the speed itself.

As the torque produced by the rotary fan upon the carrier depends on the blade area and pitch, on the speed of rotation of the fan, on the position of the fan on the carrier with reference to the axis of revolution of the latter, and on the general or prevalent path and direction of the blast of air produced by the fan with reference to the car rier and its aXis.--these last three factors determining the lever arm of the air blast, or ratherof the reaction due-t it,I may produce the desired variation of the torque by changing any one or more of these factors. Ordinarily, however, I prefer not to varythe fan area, pitch, or speed for this purpose. both for reasons of mechanical and Y electrical sim licity, lightness, and compactness, and because such variations would affect the amount and velocity of the air blast of the fan.

I have herein illustrated and described in detail several simple fan machines in each of which there are two rotary fans directly driven by individual electric motors mounted with them on the revolving carrier, and in which variation in the path and direction of the air blast and shifting of the fan with reference to the axis of the carrier are relied .on for varying and regulating the torque.

While, however. the mechanisms here shown are the best for the purposes of mv invention at present known to me. an dwhile the invention extends to their novel features and details of operation and construction and combinations and arrangements of parts. the invention is not confined thereto. but can be I otherwise carried out and embodied.

In the accompanving drawings. Figure 1 is a side view of a fan machine constructed in accordance with my invention. certain parts being broken away; Fig. 2 is a' plan have bearings in the brackets 9.

a. seen from above, this view in a general way corresponding to Fig. 6; Fig. 8 is a fragmentary sectional view similar to the I lower portion of'Fig. 6, but at a plane of section about from that of Fig. 6; Flg. 9

is a fragmentary plan View of part of the mechanism shown in Fig. 7 with certaln tension springs added; and Fig. 10 is a fragmentary section at a surface corresponding to the line 10-10 in Fig. 7, the construction being slightly modified.

Referring first to Figs. 1 and 2, it will be seen that thecarrier 1 is arranged to revolve about an upright axis 2, and that each of the fans 3 with its electric motor 1 is fixedly but. adjustably mounted at the outer end of one of the carrier arms 5. Details of the mounting of the carrier 1 onthe axis 2 and of the electrical connections to the motors 4. are omitted to avoid needless con fusion of the drawing. It will be seen that the fan axis or shaft 6 extends more or less radially with reference to the axis 2, so that the air acted on by the fan as it rotates is thrown off more or less radially when the carrier 1 revolves. In front of the fan 3 is a directing vane 7 whose pivot spindles 8 On the lower spindle 8 is a crank membei or arm 10 which carries a centrifugal weight 11, and to a stud on this weight 11 is secured a helical tension spring 12. The lower pivot spindle 8 has also a short sector-like arm 13 carrying studs 14 that are adapted to engage the bracket 9 and serve as stops to revent the vane 7 from turning one way eyond a position of parallelism with the fan shaft 6 or the other way beyond the position shown. In most cases it will be preferred to make the vane 7 symmetrical with respect to the axis formed by the spindles 8, as shown, so that the air blast shall not tend to turn it either way. While the axis of the spindles 8 is shown vertical so that gravity does not affect the action of any of the parts, the brackets 9 are adjustably secured to the motor casinglin such a way that it can be inclined with reference to the vertical so as to make gravity supplement the spring 12 in urging the vane 7 toward the position shown, or even take its place.

When the carrier 1 and the fan 3 are at rest,the arrangements and adjustments being as shown in the drawing-the only force acting on the vane 7 is that'of the spring 12, and it accordingly assumes the diagonal position shown in Figs. 1 and 2.

When the fan 3 is started up, the vane 7 diverts at least a portion of the resulting blast of air sidewise from its radial path and thus produces a considerable torque on the carrier 1 in the direction indicated by the arrow (Fig. 2). As the carrier 1 is started into revolution and gathers speed, the centrifugal force on the weight 11 overcomes the spring 12 and swings the vane 7 around'toward a truly radial position, thus reducing the diversion of the air blast and the torque on the carrier 1 resulting therefrom. If the fan 3 is so adjusted on the arm 5 that its shaft 6 is truly radial, as

shown, the final, normal speed of revolution of the carrier 1 will always be that for which equilibrium exists between the spring 12 and the centrifugal force on the weight 11. If, however, the adjustment of the fan 3 is such that the shaft 6 is materially out of the radial position, so that the fan will roduce a torqueirrespective of the vane the tension on the sprin 12 may be made so low that the vane 7 wil lie parallel with said shaft and' so be totally without effect when the final, normal speed is reached. In either case the general direction of the air blast and the torque on the carrier 1 produced by the fan 3 are varied and regulated the spring 12 under the control of the speed of revolution of the carrier 1 and independently of the speed of rotation of the fan, so that the torque is high when the fan is started intov action on the air and is reduced after the carrier has been brought into revolution and gathered speed.

In Figs. 3 and 4 I have shown a machine in which the general path of the air blast rather than its direction is shifted to vary the torque, but which, is otherwise very similarto that of Figs. 1 and 2. As will be seen from Fig. 3, there is beneath the fan 15 a short shaft 16 mounted. to oscillate in a bracket structure secured .to-the fan motor casing, suitable means being provided to limit its movement both ways. From this shaft 16 extends upward an arm 17 carrying a circular baffle vane 18 ada ted to swing in front-of the fan 15 from t e position shown to a position where its center 'will fall in the plane of the carrierand fan axes. The shaft 16 carries a bevel gear 19 I with which meshes a similar gear 20 whose shaft 21 carries a depending arm 22 on which is a centrifugal weight 23. An adjustable tension spring 24 is connected from the arm 22 to the bracket structure. The baflle vane 18 acts under control of the centrifugal force on the weight 23 to virtually 1 and 2.

Referring, now, to the electric fan machine shown in somewhat greater detail in '1;

wea er's] Figs; 5, 6, 7 and 8, it willlbe seen that there is a hollow member 30-by which it may be suspended from a ceiling or the like, and

' that the carrier-31 has an enlarged central hub portion 32 in which are ball bearings 33 and 34 wherebyit is supported on said member 30 and"- steadied, with reference thereto. (See Fig.6.) 'Secured on the mem ber 30 at the upper side of the hub 32 is a stationary canopy 35 that inclosesmeans for transmitting current to operate the fan motors to their supply connections in the revolving carrier andfits down as close as possible to the upper edge of the hub so as to aiford the greatest possible protection to these and other interior parts.

.rings 37 wires 42 that form the current supply connections tolthe fan, motors extend down through the-web above mentioned and outthrough the 'arms43 of the carrier'31,

starting coils 44 that rest on the web being interposed in these connections; 1 For alternating current fan-motors, these coils will be inductance coils, while for direct our rent motors they will be merely resistance coils. In either case this location of the coils simplifies and lightens the fan motors and avoids complication in'their electrical connections. I 1

The fans 45 with their motors 46 (Fig. 5) are movably mounted at the outer :ends of the arms 43 so that they may swing with 5 reference to the carrier 31 in a more or less nearly horizontal plane, As shown, the end of each of the arms 43 is dividedor forked to receive a lug 47 on a bracket 48 (Figs. 5

A conical ended pivot pin 49 at and 7). n the lower side of the lug 47 seats in a socket in the lower side ofthe fork, while a pivot pin 50 whose upper end is screwed through the upper side of the fork extends down into a socket in the upper side of the lug 47. The fan and motor .are pivoted between arms 51 on said bracket 48 by means of trunnionsth'at engage the holes in the motor casing, so that the'fan and motor may be tilted up or down to,bring the fan shaft 52to any desired angle with the horizontal and vary the distribution of the air acted on, a thumb screw 53 in one of the bracket arms (Fig. 5) serving to secure the parts in adjusted position.

While various arrangements can be made, I prefer to obtain the speed controlled variation of the torque produced by a fan 45 As shown,- the transmission means comprise adqustable;

on the carrier 31 by means of the movable.

mounting of the fan and its associated parts without any gravity or spring action or any" special centrifugal weight such as set forth in connection with Figs. 1, 2, 3, and, 4. As shown, the arms'51 are so located on the bracket 48 that the center of gravity of the fan 45 with its motor 46 and the bracket is eccentric to the axis formed by the pivot,

.pins 49 and 50 (which extends in the same general direction as the axis 30), and the fan shaft axis 52 is, also eccentric to said pivot axis 49, 5f), and the outer end of the arm 43 is curvedso as to allow the pivot .49, 50 to lie well behind the rear side of the arm. (See Fig. 7.

. When the carrier 31, is at rest and the fan '45 is started, theireactionof the air on its blades will swing it aroundfwi'thjts associated parts from'any position inswhichit maybe till the bracket 48 comes against the rear side of the arm 43, (Figs'.=5 and 7 Under this condition, the fan axis "52 will be .nearly'normal to a line extending from the axis 30 of the carrier 31" through the pivot axis 49, 50, and the torque due to thefan 45.

tending to overcome stati'c'frictionand rotate the carrier in the direction of the ar row (Fig. 7) I will be almost the greatest possible, so that the carrier will be brought into revolution and gatherv speed quite rapidly. The torquecn the carrier-31 will remain constant until the'moment of thecentrifugal force of the pivotally mounted-- parts about the pivot axis 49, 50 equals andexceeds the-moment aboutfsaid'axis due to the fan 45 plus the static frictionat the piv- 7 ots, whereupon said parts willv swing out? ward on said pivot 49, 50 and the torque 'will diminish. This change in .the torque cause the distance of the center of gravity will be at a comparatively slow though pro-j gressively increasing rate at first, partly be-.

of the pivoted parts from the axis of revo- ;lution-3() will increase but slowly as said parts swing, and partly because the lever arm of the centrifugal force about the pivot 49, 50 will be initially small and will at first increase quite slowly. The rate of the change will continue to increase until the .carrier 31 has reached a fair speed; andthen, having reached its maximum. the rate of the change will (for reasons similar'to" the above) progressively diminish. I Assuming that the outward swing of the pivotally mounted parts is not sooner arrested in anv way, it will continue with the. consequent change in the torque and an accompanying increase in the carrier speed until equi librium between the centrifugal and fan moments about the pivot 49, 50 is reached. Owing to the inertia of the parts and the rapid acceleration, the carrier may in reality first reach a speed slightly iii, excess of its final normal speed and then slow down a Iso little. For such designs and fan speeds as will ordinarily be preferred, the final condition of equilibrium will be with the fan axis 52 in a very nearly radial position and the carrier 31 revolving at a speed still very moderate, so that the air from the fan'45 will be well distributed and will be felt as an agreeable intermittent breeze. By a proper design and arrangement ofthe parts, it is easy to make the normal carrier speed determined as above set forth quite as low for any practical fan speed as will in practice ever be desiredi; 4

. While the final, normal speed of the carrier 31 can not be made lower for a given fan speed than under the condition of final equilibrium between the centrifugal and fan moments, by arresting the outward swing of the pivotally mounted parts before this condition is reached the normal carrier speed can be made as much greater than this as desired,-always, of course, Within; the upper limit fixed by the torque of the fan 011 the carrier 31 when the fan is in its starting position shown in Figs. 5 and 7. I will now describe means for conveniently adjusting the carrier speed in this way without stoppage of either the carrier or the fans.

As shown in Figs. 5 and 7, the lugs 47 of the brackets 48 have each a crank arm 54 extending within the fork of the correspond ing carrier arm 43, and these crank arms are connected by rods 55 within the arms 43 to a common disk like member 56 mounted and arranged so that it may turn freely. coaxially with the member 30. As will be seen from Figs. 6 and 8, the disk part 56 is mounted on the reduced upper end of a sleeve portion 57 of an inverted cup-like part 58 keyed fast at 59 in the lower end or side of the carrier hub 32 and is held in place by a disk 60 secured to the end of said sleeve 57 by screws 61. Threaded on the lower end of the hollow member 30is a normally stationary inverted cup-like adjusting part 62 adapted to enter the part 58, and on the upper side of this part 62 is still another part 63 having an upwardly extending sleeve portion 64 that fits snugly but looselywithin the sleeve 57 of the part 58. The-ball bearing 34 already referred to rests on the upper side of the adjusting nut part 62 and supports the part 63 and through it and the part 58 steadies the carrier 31 and maintains it in alinement with reference to the member 30. In the disk member 56 are set two pinsor studs 65 whose conical heads project downward therefrom 180 degrees apart, and in the part 63 are set two similar pins or studs 66 whose heads extend up through holes in the bottom of the cup-like part 58 so that their conical upper ends may upon occasion engage the heads of aeaeia the studs 65. The lower edge of the cup 62 is knurled at 67 to afford a 00d hold for the hand in screwing it up an down on the member 30 to raise and lower the studs 66, its range of movement downward being limited b a portion of the casing of the switch 40. bviou'sly the manipulation and adjustment of the parts 62 and 66 does not in the least interfere with simultaneous running of the fans 45 and revolution of the carrier 31.

When the fans 45 are started up, they will swing outward as already described and turn the disk or collar 56 until the studs 65 thereon come against the studs 66 on the part 3. By raising the studs 66, the swing permitted the fans 45 before this happens will be shortened (owing to the conical form of the heads of the studs 65 and 66) and the normal carrier speed increased, while by lowering said studs 66 the swing thus permitted will be lengthened and the normal carrier speed reduced. As shown, the studs 66 are in substantially their highest running position, corresponding, say, to a normal speed of 30 R. P. M.- for the carrier: By lowering them -as far as possible the normal carrier speed may be made 10 R. P. M., say. By screwing the cup member 62 far upward on the member 30' from its high speed position so as to lift the pins 66 against the collar 56 and lift the collar 56 till the heads of its screws 61 jam against the lower side of the bearing part 33, the carrier 31 can be frictionall locked stationary with the fans 45 in thelr positions corresponding to the maximum carrier running speed; and after this is done the carrier may be swung around by hand in spite of the friction to bring the fans to any desired positions. It will be seen that the key 59 by which the part 58 is held fast in the hub 32 is in the form of a screw with a reduced inner end portion in a hole in said part 58: When the machine is set up and tested in the factory, the screw 59 will be used as a set screw until the proper position of the part 58 in the hub 32 for the desired speed range of the carrier 31 is found, and then the hole will be drilled in the spot thus determined and the screw 59 screwed home in it. Obviously the collar or disk 56 connected to the fans 45 is of service as a means for causing ing their centrifugal movement and for speed adjustment.

It has already been mentioned that the fans 45 with their motors 56 are mounted on trunnions so that they may be tilted in the brackets 48. I have observed that in addition to their propeller action on the air the fans 45 also exert a sort of paddle wheel action, which is the greater the greater the helical pitch of their blades. Owing to this them to move in unison as well as for limitpaddle wheel action and the consequent reaction, there is a moment due to the blades of each fan 45 when below the fan axis 52 that tends (the direction of rotation of the fan being clockwise) to rotate the carrier 31 in the same direction as does the propeller action of the fan, and there is a moment due to the blades when above the axis 52 that has exactly the opposite tendency. When the fan axis 52 is horizontal, as shown in Fig. 5, these moments exactly balance one another, since the distance of the fan blades from the carrier axis is the same above and below the fan axis 52, so that the lever arms of the paddle wheel reactions in these two cases are equal. When, however, the fan axis 52 is tilted downward, the lever arms of these paddle wheel reactions become unequal and there is an unbalanced paddle wheel moment opposing the propeller action of the fan. If the tilt of the fan axis 52 is considerable and the accelera tion of the fan at starting is very rapid (as is especially apt to be the case with a direct current electric fan), the paddle wheel moment may prevail over the propeller moment and the carrier 31 may start off and continue to rotate in the reverse of its intended direction. Ordinarily this is undesirable, for under this condition of running increase in the carrier speed may not diminish the torque on the carrier 31, but may even increase it, owing to the fact that the fan blades act on air that is more nearly stationary. The backward running can be obviated by reversing the direction of rotation of the fans 45 so that the paddle wheel moments shall reinforce the propeller moments; but this remedy still .leaves the paddle wheel moments practically unregulated.

I have found that dominance of the paddle wheel moments and backward running of the carrier 31 may be avoided by any means which will prevent the carrier from getting started backward, since ifthe fans 4.5 once have time to swing around into their normal starting positions, the propeller moments will prevail over the paddle wheel moments. As shown inFigs. 6 and 8, I have provided one or more dog-like stops 68 pivoted at 69 in slots in the lower side of the bearing part 7 33. When the carrier '31 rotates in the right direction, the ends ofthese dogs 68 slide freely on the upper surface of 'the part and over the fillister heads of the screws 61; but if the carrier 31 starts to rotate backward, the heads bring up against said dogs and stop it.

The machine last described involves no springs, the speed adjustment being efiec ted entirely by stops. While this mode of adjustment will give as low a minimum speed and as great a range of adjustment aswill" usually be desired, an even lower minimum under centrifugal force and make their final position of equilibrium one where the torque and speed of the carrier are less than they would otherwise be.

The construction shown in Fig. 10 allows gravity to be employed in aid of centrifugal force (in lieu of the springs 70 or in addition to them) when a very low minimum carrier speed is desired. As here shown, the conical ended pivot in 49 at the lower side of the lug 47 is replaced by a steel ball 75 seated in the conical socket in the lower side of the fork at the end of the arm 43 and engaging in a similar socket in said lug. The pivot pin 7 6 is made with its end portion 7 7 eccentric to the axis of the screw portion, so that the axis formed by the parts 75 and 77 is not vertical but slightly inclined with reference to the vertical and to the carrier axis 30. To make the minimum speed of the carrier 31 as low as possible, the pivot pin 76 is secured by'its set screw 7 8 with its end portion 77 in about the position indicated by the dotted circle 77 in Fig. 7 so that gravity will tend to swing the fan 45 and its associated parts outward toward the position where the fan shaft 52 would be radlal with reference to the carrier axis 30.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. A fan machine comprising a revolving carrier, a rotary fan adapted through its ac-' tion on the air to produce a torque thereon,

and means for varying the torque controlled by the speed of revolution of the carrier.

2. A fan machine comprising a revolving i carrier, a rotary fan adaptedthrough its action on the air to produce a torque thereon,

speed of rotation of the fan for varying and is started into action. and shall be reduced 115, and means controlled by the speed of revo- I lution of the carrier independently of the after the carrier has been brought into revo lution and gathered speed.

3. A fan machine comprising a revolving carrier, a rotary fan adapted to produce a torque thereon, and means controlled by centrifugal force due to therevolution of the carrier for varying the lever arm of the recor multiple armed carrier mounted for revoluaction due to the air blast produced by the fan so that the initial torque when the fan is started. into action shall be reduced after the carrier has been brought into revolution and has gathered speed.

4. A fan machine comprising a revolving carrier, a rotary fan adapted to produce a torque thereon, and means controlled by the speed-0f revolution of the carrier independently of the speed of rotation of the fan for shifting the axis of the fan With reference to the carrier so as to diminish the torque as the carrier gathers speed after the fan is started into action.

5. A fan machine comprising a revolving carrier and a rotary fan adapted to produce a torque tending to revolve the carrier movably mounted thereon in such wise that when it is started into action the reaction of the air causes it to assume a position in which the torque is high, and that as the carrier. is brought into revolution and gathers s eed it moves under the resulting centri gal force intoa position where the torque is less.

6. A fan machine comprising a revolving carrier and a rotary fan pivotally mounted thereon so as to swing, under the reaction of the air and in response to variation in the rate of revolution of the carrier, about an axis eccentric to that of the carrier and to its own center of gravity.

7. A 'fan machine comprising a revolving carrier and a' rotary fan pivotally mounted thereon so as to swing, under the reaction of the air and centrifugal force, about an axis extending in the same direction as that of the carrier but eccentric thereto and to its own axis and center of gravity.

. 8. An electric fan machine comprising 9.

tion about an upright axis, a supporting bracket pivoted to each arm of, the carrler so that it may swing horizontally to a limited extent, a rotary fan with an electric motor for driving it adjustably mounted on each bracket with its axis eccentric to the pivot, and means connected to said brackets for causing them to swing in unison.

9. A fan machine comprising a revolving carrier and a rotary fan adapted to produce a torque tending to revolve the carrier movably mounted thereon in such wise that when it is started into action the reaction of-the air causes it to assume a position in which the torque is high, and that as the carrier is brought into revolution and gathers speed it moves under the resulting centrifugal force into a position where the torque is less, and means for limiting the centrifugal movement, said means ,being adjustable to vary the final, normal speed of revolution of the carrier'for a the fan. v

10. An electric fan machine comprising a given speedof rotation of multi 1e armed carrier mounted for revolution aout an upright axis, a rotary fan with an electric motor for driving it pivotally mounted on each arm on an axis eccentric to its own axis and center of gravity so that it may swing horizontally outward from an inner position where the torque on the carrier produced by the fan is high into positions of successively diminishing torque, a member coaxial with the carrier and means connecting said member with both fans and motors so as to cause them to swing in unison, and adjustable means for linnting the movement of said member and the outward swing of the fans and motors.

11. A fan machine comprising a revolvin carrier and a rotaryv fan pivotally mounted thereon on an axis extending in the same general direction as that of the carrier but eccentric thereto and to its own axis and center of gravity, and so inclined with reference to the carrier axis that centrifugal force and gravity tend to swing the fan in .the same direction about the pivotal axis.

general direction as that of the carrier but eccentric to the carrier axis and to its own axis and center of gravity, said fan being tiltable with referenceto the carrier axis, and means for preventing starting of the carrier except in one direction.

13. The combination with a rotatable supporting member, of a rotatable fan disposed thereon to eiiect rotative movement of said member and means for maintaining a redetermined velocity of revolution wit out the use of a mechanical brake. 1

14:. The combination with a rotatable supporting member, of a rotatable fan disposed thereon to efiect rotative movement of said member, and means for maintaining a predetermined velocity of revolution by varying the actuating torque.

15. The combination with a rotatablesupporting member, of a rotatable fan disposed thereon to eii'ect rotative movement of said member, and means for maintaining a predetermined velocity of revolution by automatically varying the actuating torque in response to changes in the rotative speed of the fan.

16. The combination with a rotatable supporting member, of a rotatable and tiltable fan disposed thereon toeflect rotative movement of said member of means for automatically maintaining a predetermined velocity of revolution within certain limits, irrespective of the velocity of' rotation and the angle of tilt of said fan.

17 The combination with a rotatable supporting member, of a rotatable fan disposed thereon and adapted to efiect rotative movemeans ment of the said supporting member, and resilient means for regulating the driving 'torque which determines the velociity of the degree of such pivotal movement of the said fan.

19. Thecombination with a rotatable supporting member, of a otally supported on the said member, and

means for causing the said fans, when piv- V lurality of fans pivotally moved, to move for equal times and I through equal distances.

, 20. The combination with a rotatable supporting member, of a rotatable fan disposed thereon and adapted to efiect rotative movement of the said supporting member, and spring-controlled means for regulating the driving torque impressed upon the said supporting member to cause the said member to rotate at a predetermined speed.

In witness whereof, I have hereunto set my hand this 8th day of Sept, 1914. EDWARD-T. SHAW.

Witnesses: r

- A; K. NUGENT,

' O. READ.

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