US1874545A - Propeller - Google Patents

Description

L. J. KOCH Aug. 30, 1932.

PROPELLER Filed Jan. 9, 1931 2 Sheets-Sheet Aug. 30, 1932. J. KOCH 1,874,545

PROPELLER Filed Jan. 9, 1931 2 Sheets-Sheet 2 l 1 CONVEX 4; r

CONVEX I I l CONCAVE Attorney Inventor Patented Aug. 30, 1932 UNITE LYNN J. KOCH, OF ALLENTOWN, PEfi NSYLVANIA PROPELLER This invention relates to certain new and useful improvements in propellers, and the primary object of this invention is to provide a propeller for use in propelling a marine vessel or an airship as may be found desirable.

A very important object of the present invention is to provide a propeller which is capable of great pulling efiect with minimum motor speed.

A still further object of the invention is to provide a propeller of such a form in construction to be hereinafter more fully described, as will eliminate the spreading of water over the circumference of the propeller wheel area.

A still further object of the invention is to provide a propeller including a plurality of sections each of which is a complete propeller in itself, and the sections so arranged as to create in operation, equal pressure to all the sections or parts thereof in parallel direction of motion for discharging an equal amount of water at the rear of each unit as is taken in by the unit at the forward end thereof such a discharge being parallel throughout.

A still further object of the invention is to provide a propeller of the above mentioned character, and wherein each unit is of such a construction as to provide for an equal strain throughout the entire unit.

Other objects and advantages of the invention will become apparent from a study of the following description, taken in connection with the accompanying drawings where- Figure 1 is a side elevational view of a sectional propeller, showing the same as applieo to a marine vessel.

Figure 2 is an end elevational view of the propeller unit.

Figure 3 is a plan view thereof.

Figures 4 and 5 are transverse sectional views taken substantially on the lines H and 5-5 respectively of Figure 2.

Figure 6 is an end view of the propell clearly illustrating the relative positions of the several units.

With reference more in detail to the drawings, it will be apparent that the propeller may be composed of any desired number of sections, respectively including a hub'having secured or formed integral therewith the propeller blades 6. I

Each of the sections is provided with two blades extending oppositely from the hub, and it is 'to be noted that theblades join the hub tangentially as shown, the roots or inner edges of the blade being diametrically oposite one another. The blades are 0 2 0 positely curved longitudinally and in the direction of rotation of the propeller, the front surfaces of the blades being concave, and the rear surfaces being convened.

The leadingedges 9 of the blades are concaved, and the rear or trailing edges 10 convex. Each blade increases in width from the root 40f the blade to the outer end or. tip of the blade, the forward or leading edge-9 of the blade being curved a greater degree than the trailing or rear edge 10 of the blade so that as will be noted, the blades are of greater wic th adjacent their tips than adjacent the roots of the'blades.

The cutting or leading edge 9 of each blade is brought to an edge by beveling away the material from the front or convex side 7 as at-ll instead of from the rear or concaved side 8 of the blade. r

Adjacent its trailing edge each blade. is beveled on its concave or rear side -8 as at 12. Each of said blades at its root 4.- so joins the hub of the propeller that the blades extend from the hub obliquely to the axes of the hub with the leading edge of the blade at the root 4 terminating flush with the forward end of the hub, and the trailing edge of said root terminating flush with the rear end of the hub,-tl1e leading and trailing edges respectively of the blades springing from the hub at said roots tangential to the hub.

In Figure. 1 I have shown the propeller wheel-as applied to .a marine vessel designated generally 'by the reference character V. In this instance the propeller wheel 'consists of two of such sections herein described in detail the said sections being suitably keyed to the propeller shaft S. In Figure 6 I have shown the propeller wheel as consisting of three of such sections, and as is s'rares PATENT OFF CE apparent, irrespective of the number of sections to be used, it will be noted that when the sections are assembled on the propeller shaft S, each unit is set a fraction of a turn relative to the next preceding unit so that the blades extend fanwise from diametrically opposite sides of the shaft Sso that the concave surtfaces confer-into a continuous rotary surface as shown.

The concave surfaces providing the propolling surface for the propeller, it will 'be apparent that when the fluid element is gathered in by the blades, it will be forced not only rearwardly but also inwardly toward the axes of the propeller, the hollow sides of the blades holding the water in circumferonce or pipeline formation thereby delivering-the full force of water against the rear body of water by each unit instead of only part of the water being held to the rear, and the remaining part being forced radially outwardly toward the circumference of the wheel. Y

A still further advantage of an invention of thischaracter will 'be, that when not inuse, the sections may be readily stored, and furthenlth at in the event of breakage 'to oneofthe'units, the same may be replaced with facility.

It will be also noted that each propeller section is a unit in itself independent of the remaining sections'of the propeller, and that the additi'on'or removal of one or more sections will not weaken the remaining sections of the propeller; further the number of sectionscontituting the propeller maybe varied at will. I

:In making the propeller sectional, and each section or unit being practically an exact replica of the othersection, eliminates expensive individual patterns and reduces cost 7 of manufacture.

Even though I have herein shown and described the preferred'enibodiment of the in- Wention, it is to be understood that'the same is susceptible of changes, modifications and improvements coming within the scope of the appended claim.

Havingfthus described my invention, what claim as new is: p r

A propeller comprising-a :pluralityof units hvingfhubs'and oppositely projecting blades secured toLthe hub and having the inner portions thereof overlapping, said blades being longitudinally curved inopposite directions,

theiblndesoncorresponding sides of the hubs baiiag soarranged relative to one another as to extend fanwise from the propeller shaft with-thertips of the blade-edge to edge. I

testimony whereof I aflix my signa- LYNN J. KOCH.

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