US1404298A

US1404298A - Fan

Info

Publication number: US1404298A
Application number: US487489A
Authority: US
Inventors: Clarence E Jacobs
Original assignee: Individual
Current assignee: Individual
Priority date: 1921-07-25
Filing date: 1921-07-25
Publication date: 1922-01-24
Anticipated expiration: 1939-01-24

Description

C. E. JACOBS.

FAN.

APPLICATION FILED JULY 25. 1921.

Patented Jan. 24, 1922.

2 SHEETS-SHEET lflaw, @X

ATTORNEY.

. 0 E. JACOBS.

I FAN.

APPLICATION FILED JULY 25, I921-f Patented Jan. 24,1922.

- 2 SHEETS-SHEET 2.

CLARENCE E. JACOBS, OF DETROIT, MICHIGAN.

FAN.

Specification of Letters Patent.

Patented Jan. 24, 1922.

Application filed July 25, 1921. Serial No. 487,489.

a citizen ofthe United States, and residing at Detroit, in the county of Wayne and State of Michigan, haveinvented a new and Improved Fan, of which the following is a specification.

This invention relates to the construction of metal fans especially adapted for forcing currents of air to pass through the radiators of motor vehicles and wherever else currents of vapors or gases are to be moved, and its object is to provide a simple and effective structure of this character which will have great strength and which will be so stiff that it will have little vibration and therefore cause a minimum of humming or singing noise. Y

This invention consists of a pair of twoblade members having fiat hubs united together so that the blades are evenly spaced, the blades being twisted adjacent the hubs to give them the proper pitch, the metal at the edges of the twisted portions being stretched and-arched to give the blades great stiffness.

It further consists in securing a reinforcing spider to the middle portions of the blade members and in forming this spider with arched ribs to secure greater stiffness.

It also consists in the details of construction illustrated in the accompanying drawparticularly pointed out in the fan adapted to be secured by means of six screws. Figs. 7 and 8 are elevations of two modified forms of this fan.

Similar reference characters refer to like parts throughout the several views.

It has been found that at certain critical speeds fans formed of strips of sheet metal united at their middle portions are very liable to give out a more or less sustained,

note because of the vibrations of the ends of the blades.' This is especially the case where the blades are narrow next to the hubs, being cut away at this -polnt so that they may be easily bent to give the blade proper pitch. I have found that by making these blades of unusual width and stiffness at the hub, the vibrations of the ends of theblades are substantially eliminated and the tendency of the blades to change their pitch is entirely obviated.

The fan shown in Figs. 1 to 6 of the drawin is formed of two blade members and a spider. The blank for the blade members is shown in Fig. 4 and consists of the two blade portions 1 and the hub portion 2,the latter having ears 3 and holes 4 for the bolts or screws by means of which the fan is connected to the shaft or other device by which it is supported. If desired, ribs 5 may be embossed on these blade members as indicated in Fig. 4. z

The spider blank consists of a central hub portion 6 and the radial arms 7, each preferably formed with an embossed rib 8. It also has four holes 9 correspondin to the holes 4 in the blade members. hen the fan is to be assembled, the two blade members are placed upon a stationary die having at least two upwardly extendingpins which extend through the holes 4 and the movable die is brought down onto the two blade members, bending them to the desired shape.

When the blades are bent, the metal at the points 10 and 11 at each side of the central line of each blade adjacent the hub is sharply stretched and bent, up at one side and down at the other, forming arches which give great stiffness to the metal at these points and which cannot be returned to their original form except by pressure greater than that which can ever be exerted on the blades by the air through which they move. The ears 3 on the hubs of the blade members are bent up into the cups formed by this distortion of the metal, as shown in Figs.- 2 and 5.

After the first stroke of the die I prefer to position the spider on the blade members and bring the movable die down again onto the three parts to cause all three members to fit each other. Thereafter the spider may be united to the blade members by spot welding at the points.14.- and by rivets 15 at the ends of the arms if desired. I prefer to spot weld the ears 3 on the hub of each blade member to the other blade member before attaching them to the spider;

In Fig. 6 I' have shown a spider with the hub portion 18 and arms 7 and six holes .20

to receive the screws which secure thefan in' position. The ribs 22 are slightl different from those shown in Fig. 3. f desired, a spherical central boss 23 may be formed on the spider and 'corresponding bosses 24 on the blade members.

In Fig. 7 I have shown two blade members secured together by rivets 28 passin through holes in the ears 3 and the centra portions of the blades 2 which may also be secured together by spot welding at the points 29. The metal of the blades at the points 10 and 11 at each side of the central line of each blade adjacent the hub is sharply stretched and bent to give the blade the proper inclination. T e ears 3 of each blade are bent to fit in the grooves and over the ribs-5 of the other blades.

Where a two bladed fan is desired, it may be constructed as shown in Fig. 8. Here again the blades are bent and stretched at the points and 11. The spider 30 has arms 31' provided with stiffening ribs 32 which may be secured to the blade member by spot welding at the points 33.

The proportions of the various parts and the formofthe ,fan blades and spider may all be changed by those skilled in 'the art without departing from the spirit of my invention as set forth in the. following claims. I claim: v: 1. In a fan, the combination of a plurality of blade members, each consisting of a hub and two blades, the hubs of the two members being united and the blades twisted adjacent the hubs to give the blades the proper pitch and to arch and stretch the metal adacent the hubs at each side of the central lines of the blades.

2. In a fan, the combination of a plurality of blade members, each consisting of a hub and two blades, the hubs of the two members If being united and the blades twisted adjacent the hubs to give the blades the proper pitch and to arch and stretch the metalv adjacent the hubs at each side of the central lines of the blades, and a spider consistingof a hub'and arms extending along and fitting against and secured to said blades.

3. In a fan, the combination of a plurality of blade members, each consisting of a hub and two blades,the hubs of the two members being united and the blades twisted adjacent the hubs to give the blades the properpitch and to arch and stretch the metal adjacent the'hubs at each side of the central lines of the blades, and a spider consisting of a hub and arms extending along and fitting against and secured to said blades and having each arm formed with a longitudinal stiffening rib, the hubs of each blade member having ears which are attached to the adjacent blades of the-other member.

.4. A fancomprising a blade member consisting. of a hub and two blades twisted adjacent the hub to give the blades the proper pitch and to arch and stretch the adjacent the hub at each side of the central lines of the blades, and a reinforcing member attached to the blade member and consisting of a hub and an arm fitting against each blade. r y

CLARENCE E. JACOBS.