US2626741A - Fan wheel for centrifugal fans - Google Patents

Description

Jan. 27, 1953 s. c. OSBORNE FAN WHEEL FOR CENTRIFUGAL FANS Filed Oct. 14, 1950 F l G 2 F I G.

F l G 4 INVENTOR. Mam

Patentecl Jan. 27, 1953 FAN WHEEL FOR CENTRIFUGAL FANS Samuel C. OsbornaSyracuse, N. Y., assignor to Carr-incorporation, Syracuse, .N. Y., a corporation of Delaware Application October l4, 1950, Serial No. 190,170

ll Claims. -1

This invention relates to centrifugal fans and more particularly to the fan wheel of a centrifugal fan including means for imparting radial restraint to the vanes which serve as driving members therefor and which also impart angular rigidity to the wheel as a whole.

The chief object of the present invention is to provide a light-weight, economical fan wheel for a centrifugal fan.

An object of the present invention is to provide an economical strong, rigid fan wheel having novel mechanism for radially restraining the vanes to retain them in desired position.

A further object is to provide a strong, stable, rigid fan wheel mounted upon a hollow tubular shaft in which vane supporting members are provided adjacent the center of the wheel and have novel clamping means which wrap about the hubs of the supporting members to secure them to the shaft. Other objects of the invention will be readily perceived from the following description.

This invention relates to a centrifugal fan wheel which comprises, in combination, a shaft, two vane supporting disks mounted on the shaft adjacent one another, a plurality of vanes having openings therein, each disk carrying a plurality of vane securing members, the vane securing members on each disk facing in opposite directions whereby rotation of the disks in opposite directions passes the securing members through the vane openings to restrain the vanes against radial movement and to secure the vanes in desired position, and end rings secured to the opposite ends of the fans to form the wheel as a rigid, integral unit. Preferably, each disk has a hub or collar portion fitting about the shaft and clamping mechanism to force the collar in contact with the disk so that the fan wheel is securely attached to the shaft.

The attached drawing illustrate a preferred embodiment of my invention, in which Figure 1 is a View, partly in elevationand partly in section, of the fan wheel Figure 2 is a fragmentary view in side elevation illustrating the mechanism for clamping the vane supporting members to the shaft;

Figure 3 is a view in elevation of the vane clamping mechanism in open position; and

Figure 4 is a view in elevation of the vane clamping mechanism in closed position.

Referring to the drawing, there is shown a centrifugal fan including a housing 2 and a fan wheel 3. The housing 2 comprises a scroll 4, end plates 5 having inlets 6 therein and an outlet (not shown).

Fan wheel 3 comprises a plurality of vanes .1 having openings '5" therein, vanes I being sup.- ported on a hollow tubular shaft 8 which is mounted in suitable journals (not shown) supported in any desired manner by the end plates 5. The ends of vanes i preferably terminate in tabs 9 which extend through openings in end rings it] and are welded thereto to rigidly attach the vanes to the end rings to form a stable cage which need only be restrained at the middle to prevent blow-cut due to centrifugal forcescreated by rotation of the wheel. If'desired, the tabs may be omitted and the ends of the vanes brazed to the end rings.

Similar supporting members H in the form of disks are provided to support the vanes I on the shaft 8. Members [I impart radial restraint and angular rigidity as well as serve as driving members for vanes l, as hereinafter described. Each disk member H includes a cone-shaped section [2, a hub or collar l3 adapted to fit about shaft 8 and provided with slots therein (not shown) and a peripheral portion I4 extending radially of the wheel. Preferably, collar 13 has small tabs 15 extending therefrom for a purpose hereinafter described. The disks H face one another on the shaft with the similar portions 14 in contact with one another.

Portions IQ of disk I! are formed with a plurality of hook-like members 16 extending about their outer edges. Each hook it consists of a body I! and a tooth portion l8 extending therefrom spaced from portion 94, the lower edge l8 being inclined or tapered toward the cone to force the blades inward toward the shaft. Openings 19 are formed between portion I4 and tooth l8 and extend between adjacent teeth M3 on the same disk. A wall of each opening 19 is formed by the side 25} of each hook portion ll. The disks II are mounted on the shaft 8 with teeth 18 of the disks facing in opposing directions. Varies I are placed in openings [9 with the vane openings 1' adjacent teeth 18 as shown in Figure 3. Upon rotation of the disks II in opposite directions about shaft 3, the teeth It pass through openings l9 and the vanes l are securely held in desired position and restrained from radial movement by teeth [8, the walls 20 of hook portions I! of the disk tending to clamp the vanes therebetween to assist in forming a strong, rigid structure. If desired, the disks may be riveted together after the vanes are locked in position.

To attach the disks II to shaft 8, retainers 2| are provided. Each retainer 2! consists of upper member 22, and a lower member 23, such memher fitting over the collar I 3 of disk II. The members 22, 23 are similar in contour and are reversed in use. Each member consists of an arcuate portion 24 terminating in flanges 25 and 26. Flange 25 has its terminal portion 21 bent outward toward the opposite member. Openings 28 are provided in arcuate portions 24 through which the tabs l of collars 13 extend to keep the retainers from falling off during assembling of the wheel and to prevent rotation of the retainers about the shaft and collar during rotation of the wheel. Openings 29 are formed in flanges 25, 26 through which suitable fastening members 3|] extend.

Members 22 and 23 are placed about the collars l3 with tabs l5 extending through openings 28. Fastening members 30 are placed in openings 29 and employed to force members 22, 23 toward one another thereby securely clamping disk I l in place on the shaft. The retainers and the slots in the hub or collar cooperate to provide a wrapping effect when the fastening members are pulled up. In other words, there is a complete wrapping contact about the hub which permits an absolute minimum weight in the shaft so that full advantage may be taken of the weight reductions possible with the use of a hollow tubular shaft. The terminal portions 2! of flanges 25 serve in effect as stops to prevent distortion of the retainers when the collars l3 are clamped to the shaft 8.

The present invention provides an economical centrifugal fan containing a stable, rigid fan wheel light in weight and in which the vanes are securely restrained against radial movement and held in position to resist centrifugal forces created by rotation of the wheel. The support members for the vanes securely lock the vanes in position opposing radial movement due to centrifugal forces and may be formed by an inexpensive stamping operation. The support members are so designed as to provide adequate support for th fans and to permit simple, ready attachment to the shaft of the wheel to mount the vanes thereon. Retainers provided to attach the support members to the shaft may be formed economically and hold the support members securely in position without'slippage, without the use of set screws or keyways, permitting full advantage to be taken of the weight reductions possible when hollow, tubular shafts are employed. The use of a hollow, tubular shaft greatly decreases the weight and cost of the fan wheel and permits economies in manufacture to be effected.

While I have described a preferred embodiment of my invention, it will be understood my invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

I claim:

1. In a fan wheel, the combination of a shaft, two similar disk members mounted on the shaft adjacent one another, a plurality of vanes having openings therein, each disk carrying a plurality of fastening members facing in opposite directions whereby rotation of the disks in opposite directions passes the fastening members through the openings in said vanes to restrain the vanes against radial movement due to centrifugal forces, and end rings secured to the opposite ends of the vanes to form the wheel as an integral unit.

2. In a fan wheel, the combination of a hollow tubular shaft, two similar disk members mounted on the shaft adjacent one another, a plurality of vanes having openings therein, each disk carrying a plurality of hook-like members, the hooklike members on said disks facing opposite directions whereby rotation of said disks in opposite directions passes the hooks through the openings in said vanes to restrain the vanes against radial movement due to centrifugal forces, and end rings secured to the opposite ends of the vanes to form the wheel as an integral unit.

3. A fan wheel according to claim 2 in which each disk includes a cone-shaped portion having a collar at the end thereof adapted to fit about the shaft, and a peripheral portion containing the hook-like member.

4. In a fan wheel, the combination of a shaft, two similar disks adjacent one another, a. plurality of vanes having openings therein, each disk carrying a plurality of hook-like members, the hook-like members on the disk facing opposite directions whereby rotation of said disks in opposite directions passes the hooks through the openings in said vanes to retain the vanes in desired position, end rings secured to the opposite ends of the vanes, and holding members to secure the disks to the shaft.

5. In a fan wheel the combination of a hollow tubular shaft, two similar disks mounted on the shaft adjacent one another, each disk including a, cone-shaped portion, a collar adapted to fit about the shaft extending from one end of the cone-shaped portion, and a peripheral portion at the opposite end of the cone-shaped portion, a lurality of vanes having openings therein, each disk carrying in its peripheral portion a plurality of hook-like members, the hook-like members on the disk facing in opposite directions whereby rotation of the disks in opposite directions passes the hooks through the openings in the vanes to retain the disks in desired position, end rings secured to the opposite ends of the vanes, and holding members extending about the collar portions of the disks to clamp the disks to the hollow tubular shaft.

6. A fan wheel according to claim 5 in which the holding members each include an arcuate portion, a flange extending from one end of the arcuate portion, a second flange extending from the opposite end of the arcuate portion, having a terminal portion extending toward the other holding member, and fastening means extending through the flanges of the holding members to urge the holding members toward each other thereby securely clamping the disk on the shaft.

'7. A fan wheel according to claim 6 in which a tab extends outwardly from the collar portion and the arcuate portion of each holding member contains an opening adapted to receive the tab.

8. In a fan wheel, the combination of a hollow tubular shaft, two similar disks mounted on the shaft adjacent one nother, a plurality of vanes having openings therein, each disk having a radially extending portion, a peripheral member extending from the radial portion to form a hook, the bottom wall of the hook portion and the side wall of the radially extending portion with the peripheral edge of the disk forming an opening, said hook members and openings being placed successively about the periphery of the disk, the hook-like portions on said disks facing in opposite directions whereby rotation of said disks in opposite directions passes the hook portions through the openings in the vanes, the lower edge of the hook-like portions engaging the wall of the vane openings, and end rings secured to the opposite ends of the vanes to form a wheel as an integral unit.

9. A fan wheel according to claim 8 in which holding members are provided to attach the disks to the shaft, the holding members comprising an arcuate portion, a flange extending from one end of the arcuate portion, a second flange extending from the opposite end of the arcuate portion having a terminal portion extending toward the second holding member, and means extending through the flanges of the holding members to urge the holding members towards each other thereby securely clamping the disk on the shaft.

10. For use in a centrifugal fan including a housing having a scroll, end plates and an outlet, at least one end plate having an inlet, a fan wheel including a hollow tubular shaft, two similar disk members mounted on the shaft adjacent one another, a plurality of vanes having openings therein, peripheral members extending from said disk members to form hooks, the hooks on said disk members facing in opposite directions whereby rotation of the disks in opposite directions passes the hooks through the openings in said vanes to restrain the vanes against radial movement due to centrifugal forces, end rings secured to the opposite ends of the vanes, and holding members to secure the disks to the shaft.

11. For use in a centrifugal fan including a housing having a scroll, end plates and an outlet, at least one end plate having an inlet, a fan wheel including a hollow tubular shaft, two similar disk members mounted on the shaft adjacent one nother, a. plurality of vane having openings therein, peripheral members extending from said disk members to form hooks, the hooks on said disk members facing in opposite directions whereby rotation of the disks in opposite directions passes the hooks through the openings in said vanes to restrain the vanes against radial movement due to centrifugal forces, end rings secured to the opposite ends of the vanes, and holding members to secure the disks to the shaft, the holding members comprising n arcuate portion, a flange extending from one end of the arcuate portion, a second flange extending from the opposite end of the arcuate portion having a terminal portion extending toward the second holding member, and means extending through the flanges of the holding members to urge the holding members toward each other thereby securely clamping the disk on the shaft.

SAMUEL C. OSBORNE.

REFERENCES CITED The following references are of record in the flle of this patent:

UNITED STATES PATENTS Number Name Date 1,639,489 Culhane Aug. 16, 1927 2,096,926 Shawhan et a1 Oct. 26, 1937 2,357,618 Swift Sept. 5, 1944 2,392,113 Anderson Jan. 1, 1946 2,435,764 Wessel Feb. 10, 1948

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