US1110979A - Screw-propeller. - Google Patents

Description

J. P. AGAN.

SCREW PROPELLER.

APPLICATION IILED JULY 25, 1913.

Patented Sept. 15,1911.

INVENTOR.

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A TTORNE i.

THE NORRIS PETERS 60-. PHOTO L|THO.. WASHINGTON. D. C.

ling efficiency and JOHN P. AG-AN, OF LOUISVILLE, KEIITUGKY, ASSIGNUE 0F SHUMATE AND ONE-THIRD T0 FREDERICK J. LERCH,

TUGKY.

ONE-THIBD TO WILLIAM A. BOTH OE LOUISVILLE, KEN- scnnw-rnornttnn.

Specification of Letters Patent. 1 Application filed July 25, 1913.

Patented Sent. 15, 11.914. Serial No. verses.

To all whom it may concern:

Be it known that I, ,JoHNP. AoAn, a citizen of the United'States, residing at 2620 High street, in the city of Louisville, county of Jefierson, and State of Kentucky, have invented a newand useful Improvement in Screw-Propellers, of which the following is a specificatio This invention relates to screw propellers.

The screw propeller owes its propulsive effect to the reaction of the body of fluid it forces rearwardly in lines parallel with its axis. Such part of the media, in which the propeller rotates, as is thrown off in lines tangent to the axis is non-effective.

An object of this invention is to provide an improved propeller for use on various class of craft which shall be of simple construction, efi'icient in operation and possess marked advantages hereinafter mentioned.

Another object is to increase the propeldecrease the vibration generally caused by propellers of the usual construction.

The propeller of usual construction throws a percentage of the water on which it acts at a tangent, this tion so familiar in the driven vessels.

A further object is to provide a construction of propeller that will intercept that portion of the media, in which the propeller is acting, that is thrown 0d at a tangent by'the centrifugal action thereof and divert it to lines parallel with the axis.

These objects 1" attain by the novel construction set forth, and illustrated in the accompanying drawing which forms a part of this specification, in which is set forth an embodiment of in invention, but it is to be understood that changes, variations and modifications may be resorted to that come within the scope of the claims appended hereunto.

in the drawing, in which like reference characters indicate like parts in the several views; Figure 1, is a rear elevation; Fig. 2, a side elevation; Fig. 8 sections. on the lines o- 21, w re, YY, m-w and ZZ of Fig. 1.

Referring to the drawing -1 denotes the hub, that may be of any form desired; a/"" denotes the usual opening therewake of propeller causes the ebullithrong 1 for the shaft, and -3 denotes the blades, which may be attached tothe hub in any convenient, or desired manner. The arrow lindicates the direction in which the propeller is assumed to turn, 2'. e. to the right, and therefore 5 is the leading edge, and -6- the following edge of the blade. -7- indicates the propelling face of the blade and S- the rear face thereof. The blades may be of a size suitable to the class and size of craft on which they are to be used, and any kind of pitch may he employed-such as a uniform pitch, a simple increasing or simple decreasing pitch- 2'. c. increasing or decreasing from the leading to the following edge, or progressively increasing or decreasing pitch, or a 001m pound increasing or decreasing pitch from the leading to the following edge and from the hub to the periphery, but for all ordinary purposes I prefer to employ blades having a uniform pitch as illustrated. The

blade is provided With an incurved tip 9 that extends, with a decreasing pitch, across the blade from the leading edge and merges in the following edge, and is adapted to intercept, and divert rearwardly, in lines parallel with the axis, such of the fluid as may be thrown out in radial lines by the centrifugal action of the blades. The amplitude of the tip 9 is greatest at its connection with the leading edge and decreases until it merges into the following edge. It

is to be understood that the size and pitch of the incurvate tip may be varied in accordance with the size and pitch of the blades used.

In operation the leading edge cuts the water, or other media, the tip 9 intercepts and diverts any radial flow to lines parallel with the axis. An effect of the divergent streams of fluid impinging on the incurvate tips is to balance and steady the propeller, in a large measure reducing the vibrations incident to the use of the usual propeller, thus giving an easier riding boat.

That considerably better results are obtained by the use of a propeller provided with an incurvated tip in accordance with my invention, than with a propeller not so provided is clearly shown by extensive practical experiments I have made. The experiments show that a propeller constructed' according to my invention gives a the usual propeller havand that With a propeller having the tip incurvedaccording to my invention the same speed may be attained With a less number of revolutions than With a propeller of the usual construction.

Having thus described my invention so that any one skilled in the art pertaining thereto may make and use the same, I

. claim 1. A propeller comprising a hub and a blade, said blade having an incurvate tip extending, with a diminishing pitch, across the end of the blade.

2. A propeller comprising a hub and pin rality of blades pitched at transverse 111- clinations on lines oblique to the axial line of said hub, and having 'incurvate tips extending with a diminishing pitch across the ends of said blades presenting portions adapted to discharge rearwardly therefrom.

JOHN P. 'AGAN.

Witnesses: a

W. B. MUNNELL, F. H. KAPPA.

Copies of this patent may be obtained for five cents eac11, by addressing Washington, I C.

the I Commissioner of IEatents.

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