US1233115A

US1233115A - Centrifugal conveyer-fan.

Info

Publication number: US1233115A
Application number: US8992916A
Authority: US
Inventors: William S Osborne
Original assignee: CLARENCE N MACK
Current assignee: CLARENCE N MACK
Priority date: 1916-04-08
Filing date: 1916-04-08
Publication date: 1917-07-10
Anticipated expiration: 1934-07-10

Description

W. S. OSBORNE. CENTRIFUGAL CONVEYER FAN. APPLICATION FILED APR. a. 1916.

Patented July 10, 1917.

Vii'lliamofl U EOMW surfaces of the blades of the fan Wheel and ceedingly short life;

WILLIAM S. OSBORNE, 0F CANTON, OHIO, ASSIGNOR 0F ONE-HALF TO CLARENCE IN.

MACK, 0F CANTON, OHIO.

CENTRIFUGAL CONVEYER-FAN.

Specification of Letters Patent.

Patented July Ml, limit.

To all whom it may concern.

Be it known that I, WILLIAM S. OSBORNE, a citizen of the United States, residing at Canton, in the county of Stark and State of Ohio, have invented certain new and useful Improvements in Centrifugal Conveyer-Fans, of which the following is a specification.

The invention relates to improvements in centrifugal conveyer fans of the type employed in pneumatic systems for conveying materials from one point to another, and more particularly to fans for conveying abrasive materials, such as sand, coal, ashes and the like.

Fans which are employed for conveying abrasive materials are or cut through in a' very short space of time, by reason of the grinding and abrading action of the material, and the life of the fan in many cases does not exceed a week or ten days. It is thus evident that the use of fans as ordinarily constructed, for this purpose, although operating to efiiciently perform their, function for a time, is almost prohibitive on account of their exand the object of the present invention is to provide means for forming air cushions on the surfaces exposed to the impact of material passing through the fan for protecting the fan from the abrading action of the material which is being conveyed, and to prolong the life of the fan indefinitely, such means being simple in construction and not materially increasing the cost or impairing the efliciency of the fan.

The object of the invention thus set forth in general terms, is attained by providing a plurality of transverse ribs on the forward frequently worn out on the inner surface of the peripheral wall of the fan casing, which ribs are spaced a short distance apart and form pockets. In the operation become filled with air which is compressed and forms an air lining or cushion on each of the blades and on' the peripheral wall of of the fan these pockets,

the casing, for receiving the impact of the material passing therethrough.

preferred embodiment of my invention is illustrated in the accompanying drawings forming part hereof, in which- Figure 1 is an end elevation partly in section of the conveyer fan;

Fig. 2, a sectional view of the case. on line 2-2, Fig. 1, showing the fan wheel therein;

Fig. 3, a fragmentary perspective view of one of the rib plates or sections for the casing; and

Fig. 4, an enlarged sectional view showing the manner of securing the ribs to the fan blades.

Similar numerals refer to similar parts throughout the drawings.

In the embodiment illustrated, the fan comprises a, caslng 1, mounted upon a base 2, and a fan wheel 3 mounted to rotate within the casing on the inner end of a drive shaft 4 extending through an opening 5 in the rear side wall of the case, and mounted in bearings 6 supported on each side of a drive pulley 7 thereon, by means of a standard 8 at the rear side of the casing.

The casing 1 is preferably of the snail type having a substantially axial eye or inlet opening 9 in its front side wall 10, and a tangential discharge nozzle ing 11 in its peripheral wall 12, at the lower end of the casing; and the fan wheel 3 consists of a plurality of vanes or blades 13 secured by means of rivets 14 transversely of the case on a plurality of T-arms 15 Whlch extend radially from a hub 16 keyed on the shaft 4, said blades being located in planes substantially parallel with the axis of rotation of the fan wheel.

For the purpose of protecting the parts of the fan which are exposed to the impact of the material which is drawn therethrough, the inner surface of the peripheral Wall 12 of the fan casing is provided with a plurality of transverse and preferably rectangular ribs 17 spaced a short distance apart to form pockets 17 8 therebetween, said or outlet openthe peripheral 4 of the air currents as ribs being equalinlength to the interior width of the casing and being located substantially parallel with the axis of ro tation of the fan wheel; and the forward faceof each of the fan blades 13 is provided with a plurality of ribs 18 extending transversely across the blades and also, spaced apart to form pockets 18 therebetween, the length of said ribs and pockets being substantially parallel with the axis of rotation.

For the purpose of construction, and for convenience in assembling, the ribs 17 for the peripheral wall are preferably formed or cast integrallywith a plurality of rela- ;-tively short plates or sections 19 which plates are curved to conform to the shape of the peripheral wall 12 and are secured thereto in a continuous series as by means of bolts 20 entered through apertures 21, provided at the opposite ends of the sections for that purpose; and the ribs 18 are preferably secured to the fan blades 13 y means of tapered rivets 22 entered throu h correspondingly shaped apertures 23 in the ribs.

In operation, as the fan wheel is rotated by the drive pulley 7 the inner surface of wall is impinged by the air and a quantity thereof is forced into the pockets 17 and is retained and compressed therein to a substantial degree by the action they are thrown radially outward thereagamst; and likewise the fans of this type,

1 overcome by the as the forward surfaces of the blades of the fan wheel impinge the air, the pockets 18 alsobecome filled with air, which is caught and compressed therein as its inertia is action of the fan wheel. It is thus evident that the air which is retained by the pockets on the inner surface of the peripheral wall, forms a continuous layer or lining of compressed air on the entire inner surface of the peripheral wall, and that the airwhich is retained by the pockets on the forward face of the fan blades, forms a sim'lar linin thereon; so that the impinging action 0 the material drawn into the fan is receivedand cushioned by the protecting air linings in the casing and on the blades, largely limiting or preventing the grinding and wearing of the parts, and prolonging the life of the fan. In order that the power required to drive the fan shall not be increased by the presence of the transverse ribs on the peripheral wall, the fan casing is made relatively shghtly larger in diameter than is'usual in so that suflicient clearance is provided around the periphery of the wheel for the most eflicient operation of the fan; and on account of a tendency of the ribs 18 on the face of the fan blades to form eddy currents, when they are all of the same size, said ribs are preferably gradually increased inthickness toward the tips of the blades so that their forward faces will lie in a radial plane and the outer walls of the pockets formed between them will serve to effectively prevent the air from whirling outwardly from one pocket to another.

I claim 1. A fan includin a casing having an inlet opening, an out et'opening, and a peripheral wall, a wheel mounted to rotate in the casing having a plurality of blades, there being a plurality of transverse ribs spaced apart on the inner surface of the peripheral wall and a plurality of trans verse ribs spaced apart on the forward face of the fanblades.

2. A fan includin a casing having an inlet opening, an out et opening and a peripheral wall, a wheel mounted to rotate in the casing, and .a plurality of transverse ribs spaced apart on the inner surface of the peripheral wall.

3. A fan including a casing having an inlet opening and an outlet opening, a wheel mounted to rotate in the casing having a plurality of radial blades, and a plura ity of'transverse ribs spaced apart on the forward face of the fan blades, the planes of the blades and the length of the ribs being substantially parallel with the axis of rotation.

4. A fan including a casing having an inlet opening and an outlet opening, a wheel mounted to rotate in the casing having a plurality of transverse blades, and a plurality of transverse ribs spaced apart on the forward face of each of the fan blades and having their forward edges lying in the same radial plane.

5. A fan includin a casing having an inlet opening, an out et opening and a pcripheral wall, a wheel mounted to rotate in the casing, and a plurality of plate sections secured in a continuous series on the inner surface of the peripheral wall, said sections having a plurality of air pockets formed therein.

6. A fan includin inlet opening, an out et opening and a peripheral wall, and a wheel mounted to rotate within the casing and having a plurality of blades, there being a plurality of air pockets on the inner surface of the peripheral wall and on the forward faces of the fan blades.

7. A fan includin a casing having an inlet opening, an ou et opening and a pcripheral wall, and a fan wheel mounted to rotate within the casing, there being a plurality of air pockets on the inner surface of the peripheral wall.

8. A fan including a casing having an a casing having an weenie inlet opening and an outlet opening, and a Wheel mounted to rotate Within the casing and having a plurality of radial blades, there being a plurality of air pockets on the forward surfaces of the blades, the planes of the blades being substantially parallel with the axis of rotation.

9. A centrifugal conveyer fan including a wheel having blades and a casing having a wall, said blades and Wall having ribs forming air retaining pockets on the sur- :laccs which impinge and are impinged by the air.

10. A rentrifugal conveyer fan including a wheel having blades Whose faces are substantially parallel to the axis of rotation of the wheel. said blades having ribs forming air retaining pockets on the surfaces Which impinge the air.

I]. A centrifugal conveyer fan including a casing having a Wall provided with ribs forming air retaining pockets on the surface which is impinged by the air.

l2. A centrifugal conveyer fan including a: Will a Wheel having blades wall, said blades and wall being provided with a plurality of air retaining pockets in the surfaces which impinge and are impinged by the air.

13. centrifugal conveyer awheel having blades Whose stantially parallel to the anti the wheel, each of said blade with a plurality of air reta the surfaces which iin ii. A centrifugal eon "in including a casing having a Wall provided With a plurality of air retaining pockets in the surface which is impinged by the air.

. 15. A centrifugal conveyer fan having in combination, a casing having a, vi -all and an impeller having blades said Wall and blades having surfaces exposed to the impact of material passing through the fan, and means for forming a protecti e air cushion on one of said surfaces.

fan including :laces are subs of rotation of heing provided 11g; pockets in i/VlLLlAh'i' S. afltiritllltl lllfl.

and a casing having a f