US1954309A

US1954309A - Propeller

Info

Publication number: US1954309A
Application number: US617663A
Authority: US
Inventors: Cutolo Mario Alessandro
Original assignee: Individual
Current assignee: Individual
Priority date: 1932-06-16
Filing date: 1932-06-16
Publication date: 1934-04-10
Anticipated expiration: 1951-04-10

Description

April 10, 1934. M. A. CUTOLO PROPELLER Filed June 16 1932 2 Sheets-Sheet l Inventor a mrz'o i [262020 M M. A. CUTOLO April 10, 1934.

PROPELLER 2 Sheets-Sheet 2 Filed June 16, 1932 Inventor Q By Wm flflomey Patented Apr. 10, 1934 STATES PATENT OFFICE 8 Claims;

My invention relates to improvements in pro pellers, and an important object of the invention is to provide a propeller of maximum efficiency with smallest bulk, and low cost and ease of manufacture.

Another important object of my invention is to provide a propeller having these desirable characteristics and also the capabilityof being made in one piece, or of several pieces of material.

It is also an important object of my invention to provide a propeller having these features, wherein a plurality of foils making up a pair of blades provided, the foils or planes being related to each other as to width, pitch, and length, so

" as to obtain the maximum aero-dynamic effect within the limits of efflciency.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the drawings, wherein for purposes of ilustration I have shown a preferred embodiment of the invention.

In the drawings:--

Figure 1 is a front elevational view of the embodiment which indicates the relationships of the planes of each blade.

Figure 2 is an edge elevation of the embodiment.

Figure 3 is a side elevational view thereof.

Figure 4 is a sectional view taken approximately on the line 44 of Figure 1.

Figure 5 is a sectional view taken approximately on the line 55 of Figure 1.

Figure 6 is a perspective view of the embodiment.

Referring in detail to the drawings, wherein like numerals refer to like parts throughout the same, the numeral 5 generally designates the embodiment of the invention, the numeral 6 one blade thereof and the numeral '7 the other blade thereof.

Each blade 6, '7 may be said to be composed of three sub-blades or planes, 6a, 6b, and 6c, and 7a, 7b, and 70, respectively.

If desired opposing sub-blades such as subblades 6a and 7a may be constituted by a single F ordinary propeller, the device being constructed by placing propellers of successively reduced size one behind the other on the same axis. While it is expressly included within the invention to so form the propeller of the invention in this manner, a specific provision of the invention is to provide the invention constructed of a single piece of material, the form and arrangement thereof being especially adapted to such economical and mechanically efficient construction.

Each of the sections which are constituted by opposing sub-blades such as the section 6a, 7a, the section 622, 7b, and the section 60, 7c, are similar in cross section, length, width, and pitch. However, each section differs from its neighbor in width, length, and if desired, in pitch.

In a desirable arrangement, the section Go, To may have a maximum Width of 27 degrees of a circle, the section 612, '71) maximum width of degrees of a circle, the section 60, 7c maximum Width of 24 degrees of a circle. Taking the length of the section 6a, m, as the criterion, the section 6b, 7b will have blades having a ten percent less length than the blades of the section 611, 7a, while the section 61), lb will have blades of a length ten percent less than the length of the blades in the section 6b, 7b.

The front elevation of each of the sections is typified by that of section 6a, 7a, Figure 1. However, the blades of the succeeding sections are placed as indicated in Figure 5 so as to meet the neighboring edges of the neighboring sections. Toward the outer ends of the blades some separation between the edges of the blades obtains as indicated by the sectional View, Figure 4.

Adjacent the hub portion of the embodiment generally indicated 8, the hub portions 9, 10, 11 of the blade 6, the hub portions 12, 13, 14 of the blade 7, are culped and concaved as shown in the drawings, so that the hub formation resulting from such treatment of the inner end portions of the sub-blades is substantially continued as an axially extended cylindrical formation which is best seen in the perspective Figure 6. This gives a continuous aero-dynamic surface, and provides for continuity in the pressures exerted by the device of the invention against the medium in which it is operated.

As indicated in the sectional views in Figures 4, 5, the sub-blades are relatively thin, and each of them in each blade has its own curvature and displacement. As seen the cross sections are somewhat reduced in successive sub-blades away from the sub-blades of the section 6a, 711.

It will be observed that each blade 6, 7 occupies approximately '76 degrees of the circle which defines the sphere of action of the propeller, so that the sum of the acting blades of the device of the invention is that corresponding to 152 degrees of the sphere of action. Due to the fact that the construction furnishes main blades which are superior to merely wide blades of the same width as the sum of the width of the sections of the invention, the difficulties ordi narily met with in the construction and operation of such ordinary wide bladed propellers are obviated in the case of the invention by the peculiar formations thereof as described above.

It will be observed that the action of the propeller of the invention is not the same as the action of a propeller constructed with a pair of single, undivided blades, since the successive subblades are scientifically reduced to have a specific aero-dynamic compensation which obviates the unequal action characteristic of wide bladed propellers. At the same time, a greater power can be exerted upon a medium through the use of a propeller of the invention than can be achieved by wide bladed propellers not having such compensatory characteristics.

The device of the invention may be constructed of metal or of any suitable composition, and the design of the principles thereof applied and used in any place and for any work requiring a propeller or similar device operating in a fluid medium.

Though I have shown and described herein a preferred embodiment of the invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in material and structure and arrangement of parts, within the spirit of the invention and the scope of the subjoined claims.

What is claimed is:

1. A propeller comprising an elongated hub, a plurality of circumferentially spaced blades on said hub, each of said blades consisting of a plurality of sub-blades projecting radially from and merging into said hub, said sub-blades arranged one behind the other and decreasing progressively in length from front to rear, said sub-blades having a portion of their adjacent edges connected together from said hub to a point radially outward of said hub but inward of the outer ends of said sub-blades, the remaining portions of said adjacent edges being spacec apart.

2. A propeller comprising an elongated hub having circumferentially spaced blades thereon, each of said blades consisting of a plurality of sub-blades arranged one behind the other and circumferentially arranged so as to avoid overlapping each other, said sub-blades having a portion of their adjacent edges connected from said hub to a point radially outwardly removed from said hub but spaced inwardly from the outer ends of said adjacent edges, the remaining portion of said adjacent edges being circumferentially and axially spaced.

3. A propeller comprising an elongated hub having circumferentially spaced blades thereon, each of said blades comprising a plurality of sub-blades arranged one behind the other along and merging into said hub and being successively radially shorter from front to rear, said sub-blades being circumferentially displaced so as to avoid overlapping thereof, a portion of adjacent edges of adjacent blades extending from said hub to a point radially outward from said hub but inward from the outer end of said adjacent edges being connected, the remaining portion of said adjacent edges being separated.

4. A propeller comprising an elongated hub having circumferentially spaced blades thereon,

each of said blades comprising a plurality of sub-blades arranged one behind the other along and merging into said hub and being successively radially shorter from front to rear, said sub-blades being circumferentially displaced so as to avoid overlapping thereof, a portion of adjacent edges of adjacent blades extending from said hub to a point radially outward from said hub but inward from the outer end of said adjacent edges being connected, the remaining portion of said adjacent edges being separated, each of said sub-blades having a convex face and a concave face, the convex and concave faces of adjacent sub-blades merging where said adjacent edges are connected.

5. A propeller comprising an elongated hub having circumferentially spaced blades thereon, each of said blades comprising a plurality of subblades arranged one behind the other along and merging into said hub and being successively radially shorter from front to rear, said sub-blades being circumferentially displaced so as to avoid overlapping thereof, a portion of adjacent edges of adjacent blades extending from said hub to a point radially outward from said hub but inward from the outer end of said adjacent edges being connected, the remaining portion of said adjacent edges being separated, the said remaining portion of the forward one of the edges of each of said sub-blades being radially outwardly and rearwardly curved, and the said remaining p rtion of the back one of the edges of each of said sub-blades being relatively straight.

6. A propeller comprising a hub, a plurality of circumferentially spaced blades extending therefrom, each of said blades comprising a unit consisting of a plurality of edge to edge connected sub-blades of circumferentially successively smaller length, said sub-blades being arranged along said hub, outer portions of adjacent side edges of adjacent ones of said subblades being circumferentially and axially spaced with respect to said hub.

7. A propeller comprising a hub, a plurality of circumferentiallyv spaced blades extending therefrom, each of said blades comprising a unit consisting of a plurality of edge to edge con-- nected sub-blades of circumferentially successively smaller length, said sub-blades being ar ranged along said hub, outer portions of adjacent side edges of adjacent ones of said sub-blades being circumferentially and axially spaced with respect to said hub, the forward ones of said outer portions being radially outwardly and rearwardly curved.

8. A propeller comprising a hub, a plurality of circumferentially spaced blades extending therefrom, each of said blades comprising a unit consisting of a plurality of edge to edge con-- nected sub-blades of circumferentially succes sively smaller length, said sub-blades being arranged along said hub, outer portions of adjacent side edges of adjacent ones of said subblades being circumferentially and axially spaced with respect to said hub, the forward ones of said outer portions being radially outwardly and rearwardly curved, the rearward ones of said outer portions being substantially straight.

MARIO ALESSANDRO CUTOLO.