US921744A - Ventilating-fan for mines. - Google Patents

Description

W. D. SCOTT. VENTILATING PAN FOR MINES. AYPLIGATION FILED MAY 12. 1908 INVENTOR- ATTIJRNEY.

Patented May 18, 1909.

PATENT ()FFTQF.

WILLIAM D. SCOTT, OF BRIDGEPORT, OHIO.

VENTILATING-FAN FOR MINES.

Application filed May 12, 1908.

T 0 all whom it may concern:

Be it known that I, WILLIAM D. Soon, a citizen of the United States of America, and resident of Bridgeport, county of Belmont, and State of Ohio, have invented certain new and useful Improvements in Ventilating-Fans for Mines, of which the following is a specifi cation.

This invention relates to improvements in ventilating fans for mines, and it has for its primary object to provide a blast-fan having a maximum capacity for forcing air throughout a mine.

A further object is to provide a ventilating fan for mines having blades which are curved in such manner as to effect a most efiicient gathering and discharge or delivery of the air.

Another object is to provide a fan of the character described which may be operated at any speed without there being any tendency to baffle. And a still further object of the invention is to provide a ventilating fan having a pair of separated bearings and means whereby the blades are braced at opposite ends, preventing breakage or bending of the latter while in operation.

In describing the invention in detail, reference is herein had to the accompanying drawing, forming a part of this specification, in which Figure 1 is a longitudinal section of the invention; Fig. 2 is a cross section on the line 2-2, Fig. 1; Fig. 3 is a rear end view of the invention; Fig. 4: is a detail perspective view of a hub-bearing; and Fig. 5 is a similar view of a bearing showing a modified form of arm.

Referring to said drawing, in which like reference characters designate like parts throughout the several views, 1 and 2 indicate supports in which is journaled the horizontal shaft 3 having a drive-wheel 4 mounted thereon, said shaft being located centrally of a casing 5 which is firmly mounted, by means of angular lugs 6, upon a suitable base, as the beams 7. The arrow on said pulley shows the direction of rotation of the fan.

Fixed upon the shaft 3 is a pair of hub- like bearings 8, 8 having a plurality of integral radial spoke-like arms 9. Mounted upon said arms is a plurality of curved bars or members 10 which have firmly attached thereto a plurality of twisted fan-like blades 11 which are disposed diagonally to the axis of the shaft 3, within the casing 5. Said blades are made of such size with relation to Specification of Letters Patent.

Patented May 18, 1909.

Serial No. 32,466.

that of the casing as to just clear the latter at a point substantially midway between its ends.

Eachblade is mounted so that it closely approachesv the shaft at the point where it crosses the latter; or, as is shown in Fig. 1, the blade may be provided with a notch 12 in which the shaft is received, means being thus provided whereby the shaft is closely embraced. The purpose of this arrangement of the blades with relation tothe shaft is to prevent the rearwardpassage of air currents between the blades and the shaft. Baflling of fans operated at high speed frequently re sults, such baffling being due to the leaving of a clear passage for the return of air along the operating shaft, and this baffiing, as well as all churning of the air, is effectually prevented in the present device by the means just described.

The intake ends of the blades project slightly outward from the rear end of the casing, as shown, for increasing their airgathering capacity, while the delivery ends of said blades are preferably inclosed by the casing for directing the air forward for preventing the tendency to a whirlpool effect which would otherwise be created.

The blades are formed from an oblong sheet of metal of substantially oval shape, and the curvature of said blades is in opposite directions at their opposite ends, that at the rear or intake end being more pronounced than that at the opposite or delivery end.

The blades are attached at points adjacent to their opposite ends to the bars or members 10 which are rigidly carried by the radial arms 9, said members being curved to correspond to the curvature of the blades at the parts to which they are attached. Said members 10 are connected to said arms by means of rivets or bolts 14, as shown. Said arms may be rectangular in cross section, as shown in Figs. 1, 2, 3 and 4., or may be mortised on their front sides, as shown at 15 in Fig. 5. In this latter construction the inner ends of the members are received in the mortises, in which position they are more rigidly held and lateral displacement thereof is effectually prevented.

The provision of the two separated hubbearings located so that the blades are supported at points adjacent to their opposite ends renders the blades much more rigid and substantial than would be the case were a single centrally located hub employed, as is usual in such devices.

Having thus described my invention, what I claim as new, and desire to secure byLetters Patent, is

1. A ventilating fan comprising in combination with a casing, a longitudinal shaft centrally mounted therein, a plurality of hubs mounted on said shaft, and a series of blades secured to said hubs and extending across said casing, said blades comprising ovally oblong sheets having their bodies spirally conformed along their major axes and having the curve of their receiving ends continued and accentuated to increase their air intercepting qualities.

2. A ventilating fan comprising in combination with a casing, a longitudinal shaft centrally mounted therein, a plurality of hubs having radiating arms secured to said shaft and a series of blades mounted on said arms, said blades being ovally oblong in shape and spirally twisted, and having their and a series of blades secured to said hubs, and 1 extending across said casing, said blades comprising ovally oblong sheets and being spirally twisted along their major axes and having their intake ends continued and the curve thereof accentuated to increase their air-intercepting capacities, said blades also diagonally crossing and closely overlying said shaft to close any possible backpassage therebetween.

In testimony whereof I afliX my signature 40 in presence of two subscribing witnesses.

WILLIAM D. SCOTT.

Nitnesses B. E. ADAMs, H. E. DUNLAP.

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