US1933947A

US1933947A - Suction fan wheel

Info

Publication number: US1933947A
Application number: US651874A
Authority: US
Inventors: Weber Max
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-01-16
Filing date: 1933-01-16
Publication date: 1933-11-07
Anticipated expiration: 1950-11-07

Description

Nov. 7, 1933. M, WEBER 1,

SUCTION FAN WHEEL Filed Jan. 6, 1933 2 Sheets-Sheet 1 Nov. 7, 1933. M. WE BER SPUCTION FAN WHEEL Filed Jan. 16, 1933 2 Sheets-Sheet 2 Patented Nov. 7, I 1933 UNITED STATES PATENT" orrica SUCTION FAN WHEEL Max Weber, (Ihicago, 111. Application January 16, 1933. Serial No. 651,874 7 Claims. (01. 170-159) The present invention relates generally to fan wheels of the suction variety. More particularly, the invention relates to that type of suction fan wheel which is adapted to operate in air or other bodies of gaseous or aeriform fluid and to be driven at a comparatively high speed from any suitable source of power, and comprises a hub and a plurality of blades which are connected to and radiate from the hub and are angularly disposed with respect to the plane of rotation of the Wheel so that they serve duringdrive of the wheel to draw the air or fluid from the front of the wheel and force it rearwardly under pressure and at increased velocity from the back side.

One object'of the invention is to provide a suction fan wheel of the type under consideration in which the hub tapers to a point at the front side of the wheel, that is, in front of the suction faces of the blades, and is so formed that it 20 eliminates pressure resistance in front of the hub and serves to deflect the air upwardly and rearwardly into the path of the rear or pressure faces of the blades.

Another object of the invention is to provide a fan wheel of the last mentioned character in which the tapered front part of the hub has curved surfaces which form at the root or inner end parts of the blades continuations of the suction surfaces and operate during drive of the fan wheel to produce a suction effect whereby the air directly in front of the hub is drawn into position for contact with the 'pressure faces of the blades, and also to assist rotation of the fan wheel when the wheel is moved forwardly at high speeds, such, for example, as is the case when the wheel is used in connection with the cooling of an automobile'motor.

A further object of the invention is to provide a suction type fan wheel in which the blades are of such number and are so shaped and con structed that rotation or form resistance, as well as friction resistance, is reduced to a minimum, and they permit the wheel to be driven at comparatively high speeds without noise and with an exceptionally low power consumption in proportion to the amount of air or fluid displacement.

In addition, it is contemplated as one of the objects of the invention to provide a fan wheel of the suction type which is generally of new and improved construction, may be produced at a low and reasonable cost and is extremely efiicient in operation.

Other objects of the invention and the various advantages and characteristics of the present fan construction will be apparent from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the con- 6 clusion hereof.

In the drawings which accompany and form a part of this specification or disclosure and in which like numerals of reference denote corresponding parts throughout the several views:

Figure 1 is a side view showing a fan wheel embodying the invention applied to an automobile motor;

Figure 2 is a front view of the fan wheel;

Figure 3 is a horizontal section taken on the line 3-3 of Figure 2 and illustrating in detail the cross sectional construction .of the hub and pulley which is connected to and forms an integral part of the rear end of the hub;

Figure 4 is an enlarged front the blades of the fan wheel;

Figure 5 is a transverse section taken on the line 5-5 of Figure 4 and illustrating in detail the construction and shape of the hub surfaces which form continuations of the inner end portions of the suction faces of the blades and serve, during drive of the fan, to produce a suction efiect whereby the air directly in front of thehub is drawn into position for contact with the pressure faces of the blades;

Figure 6 is a transverse section taken on the line 6-6 of Figure 4 and showing the cross sectional shape and the angularity of the blade at the root portion, that is, at the point where the blade is joined to or united with the hub;

Figure 7 is a transverse section taken on the line 7-7 of Figure 4 and showing the cross sectional shape and the angularity of the blade at approximately one-sixth of the way from the inner end of the blade to the outer end;

Figure 8 is a transverse section taken on the line 8-8 of Figure 4 and showing the cross sectional shape and the angularity of the blade at approximately one-third of the way from the inner end of the blade to the outer end;

Figure 9 is a transverse section taken on the line 9-9 of Figure 4 and showing the cross sectional shape and the angularity of the blade at approximately one-half of the way from the innerend of the blade to the outer end; 105

Figure 10 is a transverse section taken on the line 10-10 of Figure 4 and showing the cross sectional shape and the angularity ofthe blade at approximately two-thirds of the way from the inner end of the blade to the outer end; and

View of one of 7 Figure 11 is a transverse section taken on the line 1111 of Figure 4 and showing the cross sectional shape and the angularity of the blade at approximately five-sixths of the way from the inner end of the blade to the outer end.

The fan wheel which forms the subject matter of the invention is of the suction variety or type and is adapted to be used in connection with the moving of air or other bodies of gaseous or aeriform fluids. It consists of a hub 12 and five blades 13 and, for purpose of illustration, is shown in Figure 1 of the drawings in connection with an automobile A. The automobile A is shown more or less diagrammatically and embodies a frame or chassis F upon the front end of which is mounted a motor M and a radiator R. The motor is of the internal combustion type and embodies at one side thereof an intake manifold I and a carburetor C. The radiator R is mounted on the frame or chassis F in front of the motor and is connected to the water jacket of the motor M so that the water circulates therethrough for cooling purposes, as well understood in the art. The fan wheel is located directly behind the radiator and is adapted during drive thereof to draw air through the radiator and force it rearwardly around the motor M. It is carried by a horizontally extending stub shaft S which extends longitudinally of the frame of the automobile and has the rear end thereof supported rotatably in a bracket B. The latter is fixedly secured to the front end of the motor M. The front end of the stub shaft extends into an open-ended, cylindrical socket 14 in the rear end of the hub 12 of the fan wheel and is secured fixedly to the hub for fan wheel-driving purposes by means of a pin, key or set screw (not shown). The fan wheel is driven by means of an endless belt 15. This belt extends around and is driven by a circular element or pulley 16 on one of the operating shafts of the motor, such, for example, as

the cam shaft, and extends around and serves todrive a pulley 1'7 at the rear end of the hub of the fan wheel. When the motor M is in operation, the fan wheel is driven through the medium of the belt 15 and the pulleys 16 and 17 and operates to draw air through the radiator R and to force it rearwardly around the motor M for cooling purposes. The pulley 1'7, as shown particularly in Figure 3 of the drawings, is formed as an integral part of the hub 12 and consists of a pair of annular flanges 18 and 19 which are spaced apart to form a groove for the belt 15. The flange 18 is located in front of the flange 19 and embodies a front face 20 which is conical and is so tapered that it unites with the hub at the central portion thereof. By employing the conical face 20, the air which is projected rearwardly by the fan wheel is deflected slightly outwardly in order to produce a more efficient cooling of the space behind the radiator R.

The fan wheel is preferably in the nature of a one piece aluminum casting although if desired it may be formed of molded composition material or it may be drop forged, stamped or otherwise formed; The blades 13 radiate from the central portion of the hub 12 and are spaced equal distances apart. By virtue of the fact that there are five blades, each blade extends at an angle of 72 with respect to the two adjacent blades. The blades 13 embody suction faces 21 at the front thereof and pressure faces 22 at the back, and are angled with respect to the plane of rotation of the fan wheel so that the suction faces operate during drive of the wheel to draw air rearwardly throug the radiator R into contact with the pressure faces 22. The latter in turn, effect rearward propulsion of the air around the motor M. The pressure faces are in the form of longitudinally or helically twisted flat surfaces and at the motor inner ends of the blades extend rearwardly at an angle of 42 with respect to the plane of rotation, as shown in Figure 6.- At one-sixth of the distance from the .inner ends of the blades to the outer ends, the

pressure faces 22 are inclined or angled at 40 with respect to the plane of rotation. At onethird of the distance from the inner ends of the blades to the outer ends, the pressure faces extend rearwardly at an angle of 37 /2 with respect to the plane of rotation, as shown in Figure 8. Halfway between the inner and outer ends of the blades, the pressure faces extend rearwardly at an angle of 35 with respect to the plane of rotation of the fan wheel. At two-thirds the way from the inner ends of the blades to the outer ends, the pressure faces extend rearwardly at an angle of 32 Az from the plane of rotation. At fivesixths of the way from the inner ends of the blades to the outer ends, the pressure faces extend rearwardly at an angle of 30 with respect to the plane of rotation of the fan wheel, as shown in Figure 11. By virtue of the fact that the pitch of the pressure faces of the blades decreases 2 /2 every sixth of the distance from the inner ends of the blades to the outer ends and the pressure faces at the root or inner end parts of the blades are inclined rearwardly at an angle of 42 /2" with respect to the plane of rotation, each blade, during rotation of the fan wheel, produces a column or stream of air which flows spirally. By reason of the fact that five blades are employed, the fan wheel produces five distinct helical or spiral columns of air which flow around the motor in the manner indicated by arrows in Figure 1 of the drawings. An advantage and characteristic of developing spiral or helical streams of air around the motor M is that there are no dead air spots around the motor and. a continuous supply of fresh air to the carburetor C is assured. An additional advantage or characteristic of having the blades of the fan wheel arranged and shaped so as to produce spiral streams of air is that maximum efficiency is obtained with respect to cooling of the motor M and the air behind the radiator is constantly evacuated. By forming the pressure faces of the blades in the manner hereinbefore set forth, friction resistance is reduced to a minimum. The conical front face 20 of the flange 18 of the pulley 17 operates, as previously' pointed out, to deflect outwardly the air emanating from the pressure faces of the blades 13 and results in the helical or spiral streams of air being deflected so that they envelop and travel around substantially all portions of the motor.

The leading edges of the blades 13 are substantially straight, as shown in Figures 2 and 4. The extreme outer or tip portions of the blades are rounded and are substantially semi-circular in conformation. The trailing edges of the blades are curved and the central portions of the blades are slightly less than one-half the length of the blades.

The suction faces 21 of the blades are convex, as particularly indicatedin Figures 6, '7, 8, 9, 10 and 11. The blades are of maximum thickness near the leading edges thereof and the suction faces 21 are sharply curved adjacent the leading edges. The portions of the suction faces adjacent to the trailing edges of the blades are more gradually curved. The shape or conformation of the suction faces 21 is such that during rotation of the fan wheel, the air is drawn into contact with the pressure faces 22 at low velocity. A further attribute or characteristic of the specific shape or conformation of the suction faces of the blades is that form or rotational resistance is reduced to a minimum and there is no noise produced during drive of the fan wheel at high speeds.

In order to destroy pressure resistance in front of the hub of the fan wheel and to increase the efiiciency of the wheel, the front end of the hub is formed so that it tapers forwardly to a point or apex part 23 and embodies around the periphery thereof five curved surfaces 24. These surfaces are located between the root or inner end' parts of the blades 13 and extend from the apex part 23 to substantially the central portion of the hub. They are concave and slant rearwardly in a direction opposed to that of rotation of the wheel. The front portions of the surfaces 24 are shaped so that they are in the nature of continuations of the leading edges of the blades 13 and extend from the apex part 23 to the leading edges of the blades. The side portions of the surfaces 24 join .the suction faces 21-of the blades and are in the nature of continuations thereof. In addition, they operate to produce suction during rotation of the fan and are shaped so that the air which is drawn into contact therewith by suction effect, is directed to the pressure faces 22 of the blades. By shaping the front end of the hub so that it tapers to a point or apex part 23 and embodies the rearwardly extending, curved or arouate faces 24, pressure resistance in front of the fan wheel is eliminated and the front end of the hub operates, during drive of the fan wheel, to draw the air at the center of the wheel rearwardly and to project or direct it into contact with the pressure faces of the blades which, as previously pointed out, force the air rearwardly in helical or spiral streams. The rear portions of the surfaces 24 join the conical front face 20 of the flange 18 in arcuate lines 25, as shown in Figures 2 and i. The surfaces 24, in addition to increasing the efficiency of the fan wheel, reduces the power necessary to drive the wheel at high speeds in that the air impinging thereagainst has a tendency to rotate the fan. One of the features of shaping the blades so that the pressure and suction faces are of the character described is that the air is drawn through all portions of the radiator uniformly and at a low velocity with the result that efficient cooling of the water in the radiator is effected.

When the motor M of the automobile, is in operation and the fan wheel is driven by way of the endless belt 15 and the pulleys 16 and 17, the suction faces 21 of the blades 13 operate to draw air from in front of the radiator R through the radiator and into contact with the pressure faces 22 of the blades. These last mentioned faces, as previously pointed out, deflect the air rearwardly at an increased velocity and in the form of five,

spiral or helical streams which flow around the motor M. This spiral or helical flow of the air streams around the motor serves to cool the motor and in addition, insures a fresh supply of air to the carburetor C. The work of the suction faces 21 of the blades 13 of the fan wheel is augmented by the curved, rearwardly slanting surfaces 24 on the front end of the hub. These surfaces, as previously-pOinted out, produce a suction effect during drive of the fan wheel and direct upwardly into the path of the pressure faces of the blades, the air directly infront of the fan wheel. As a result of the hub formation, there is little, if any, pressure resistance as far as the fan wheel is concerned, and but a minimum amount of power is necessary to drive the fan wheel at high speeds due to the torque produced by the surfaces 24 of the hub in response to impingement of air thereon. By employing five blades instead of four or six or any other number, the fan wheel is harmoniously balanced.

In practice it has been found that a twenty cubic feet of air per minute and requires an input of approximately 0.563 horse power to drive it; at 2000 revolutions per minute, the fan displaces approximately 6480 cubic feet of air per minute and requires an input of approximately 1.186 horse power to driveit. At a speed of 800 revolutions per minute, a twenty inch, five bladed fan of the character herein specified drives the air at approximately 12.15 miles per hour; at 1200 revolutions per minute, it drives the air at approximately 21.70 miles per hour; at 1600 revolutions per minute, it drives the. air at approximately 26.40 miles per hour; and at 2000 revolutions per minute, it drives the air at a velocity of approximately 36.90 miles per hour. These results are directly attributable to the fact that the blades are five in number and are constructed to reduce to a minimum form and friction resistance, and that the front end of the hub substantially eliminates pres sure resistance and is shaped to augment the work of the blades by virtue of the fact that it includes the curved surfaces 24.

Whereas the fan wheel has been shown and described in connection with drawing air through the radiator of an automobile and forcing it rearwardly around the automobile motor, it is to be understood that the wheel may be used for other purposes and in diiferent ways. It is also to be understood that the invention is not to be restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. A wheel for rotation in a fluid, embodying means whereby it may be connected for rotation by a source of power and comprising an elongated hub and a plurality of angularly disposed blades connected to and radiating from the central portion of the hub and having suction and pressure faces at the front and rear sides of the wheel respectively and arranged so that during rotation of the wheel they operate to suck the fiuid from in front of the wheel and project it rearwardly, the front end of the hub being tapered to a point so as to destroy pressure resistance and embodying concave surfaces extending between the root or :inner end parts of the blades and to the point r and shaped to suck rearwardly the fluid directly in front of the hub and deliver it outwardly and rearwardly into the path of, and contact with the pressure faces of the blades in response to wheel rotation.

and arranged angularly with respect ,to the plane of rotation of the wheel and to suck the fluid from infront of thewheel and project it rearwardly during rotation of the wheel, the front end of the hub being tapered in order to destroy pressure'resistance and embodying concave surfaces joining and forming continuations of the suction faces of the blades and operating during rotation of the wheel to suck rearwardly the fluid directly in front of the. hub and deliver it outwardly and rearwardly into contact with the pressure faces of the blades.

3. A wheel for rotation in a fluid, comprising an elongated hub provided at the rear end thereof with a pulley whereby thewheel may be belt driven and a plurality of angularly disposed blades connected to and projecting radially from the central portion of the hub and having suction and pressure faces at the front and rear sides of the wheel respectively and for drawing or sucking the fluid' from in front of the wheel and projecting it rearwardly during. rotation of the wheel, the front face of the. pulley being tapered towards the, central portion of the hub and, serving to deflect outwardly the fluid projected rearwardly by the inner or root portions of the pressure faces of the blades.

4. A wheel for rotation in a fluid, comprising an elongated'hubprovided at the rear end thereof with a circular element whereby the wheel may be driven, and a plurality of'angularly disposed blades connected to and projecting radially from the central portion of the hub and having suction and pressure faces at the front. and rear sides of the wheel respectively for drawing or sucking the fluid from in front of the wheel and projecting it rearwardly during rotation of the wheel, the front face of the circular element being tapered towards the central portion of the hub and serving to deflect outwardly the fluid projected rearwardly by the inner or root portions of the pressure faces of the blades.

5. A wheel for rotation in a fluid, comprising an elongated hub provided at the rear end thereof with a circular element whereby the wheel may be driven, and a plurality of angularly disposed blades connected to and projecting radially from the central portion of the hub and having suction and pressure faces at the front and rear sides of the wheel respectively for drawing or sucking the fluid from in front of the wheel and projecting it rearwardly during rotation of the wheel, the front end of the hub being tapered in order to destroy pressure resistance in front of the wheel and embodying surfaces for sucking rearwardly the fluid directly in front of the hub and delivering it outwardly and rearwardly into contact with the pressure faces of said blades, and the front face of the circular element being tapered towards the central part of the hub and serving to deflect outwardly the fluid projected rearwardly by the inner or root portions of said pressure faces of the blades.

6. A wheel for rotation in a fluid, embodying means whereby it may be connected for rotation by a source of power and comprising an elongated hub, and a plurality of angularly disposed, equidistantly spaced blades connected to and radiating from the central portion of the hub and having suction and pressure faces at the front andrear sides of the wheel respectively for drawing or sucking the fluid from in front of the wheel and projecting it rearwardly during rotation of the wheel, the front end of the hub being tapered substantially to a point so as to destroy pressure resistance'in front of the wheel and embodying concave surfaces which slant rearwardly in a direction opposite to that of normal rotation of the wheel and join and form continuations of the root portions of the suction faces of the blades and operate during rotation of the wheel to suck rearwardly the fluid directly in front of the hub and deliver it outwardly and rearwardly into the path of, and contact with, the pressure faces of the blades.

7. A one-piece fan wheel for rotation in one direction in a fluid, embodying means whereby it may be connected for drive by a source of power and comprising an elongated hub, and a plurality of angularly disposed blades formed integrally with and radiating from the central portion of the hub and having suction and pressure faces at the front and rear sides of the wheel respectively and .for drawing the fluid from in front of the wheel and projecting it rearwardly during rotation of the wheel, the front end of the hub' being substantially pyramidal in conformation in order to destroy pressure resistance in front of the wheel and having the side surfaces thereof corresponding in number to the blades, slanting rearwardly in the opposite direction to that of rotation of the wheel, joined to the root or inner portions of the suction surfaces of the blades and operating during rotation of the wheel to suck rearwardly the fluid directly in front of the hub and deliver it outwardly and rearwardly into the path of, and contact with, the pressure faces of the blades.

MAX WEBER.