US2472357A

US2472357A - Mobile body

Info

Publication number: US2472357A
Application number: US641524A
Authority: US
Inventors: Wolf Abraham
Original assignee: Individual
Current assignee: Individual
Priority date: 1946-01-16
Filing date: 1946-01-16
Publication date: 1949-06-07
Anticipated expiration: 1966-06-07

Description

June 7, 1949. A. WOLF MOBILE BODY Filed Jan. 16, 1946 INVENTOR Abraho m U] BY ATTO R N EY Patented June 7, 1949 hair so stares her ear ore ice MBB'ILE BODY" Abraham-Wolf, Vineland,.-N., J.

Application'J'anuary' 16, 1M6; Serial No: (341}524? 2: (Elaimsa (CL. 17-0--15 9) This invention relates to mobiiebo'diesadapted to travel through fluidmedia, suelras aircraft, marine vesselsand the like; and more-particularly to improved-propeller structure therefor.

It is well'l znown that a part ofthe-resistance oiiered to the forward movementof airorait'employing propellers is d ue 'to' the compacted body of air which is built-up in the region immediately in. front of the hub a-nd inner ends of-"the blades of thepropeHer'Whichradiate-from the hub; In the vicinity of. this region, thepropeller hasvory little, if any, propelling power. This is du'e" to the fact that the air in this regionis not d riven rearwardly: by the rotating propeller; as is the air at a greater radial distancewoutwai dly' f 'rom the hub where: the: blades actu pon the air to impart rearward motion thereto; In" generalt. the same is also true of propeller driven. marine'vessels', the propellers of which encounter similar resist"- ance by the Water. made hereto-fore to eliminate; or? at. least toimate rially reduce, this compacted body of fluid medium in front of the hub andvthe: regiom therearound, but these have met with little success, so'far as I am aware.

The primary object of my. invention is: toz'provicle, in aircraft, marine vessels; and sirrrilarfm-obile bodies which'are designed to. travel through fluid media, an improved'propeller construction which will vary greatly reduce: the: aforemens ticned, compacted, fluid-body, and therefore. will greatly increase the ei'licien'cy of such: mobile bodies.

More particularlmit is an object: of my inventionto provide an improved; attachmentfor'pro pellers of mobile-bodies ofrthe type set forthabove which will be effective to increase t'he bite of the propeller blades in the fluid medium in whichit operates to thereby increase the speed of the moving body for a. given power consumption, or, for a given speed, will require less power.

Another object of my invention is toprovid'e an improved attachmentfor propell'ersas afore said which can be applied readily to most existing propellers.

Still another object of my invention is toprovide an improved propeller: structure foraircra-ft which will tend to lessenthe efi'ect'of head Wind's by drilling through the air, so-t'o speak;

A further object of my invention is to provide an improved" propeller construction for" aircraft and the like which WilltendtvmifiimiZG drifting, off course flying, and sud-den drops of the 'craft.

Still a further objector my invention isto pro vide an improved propeller construction asset Many." attempts: have: been 2 forth above'whiclr will tend-'toreduee vibration of the rotating parts to a minimumit t'i fi ing to". increase the. life: of the driving! motor therefor.v

It is also; an. object of my invention: to;- ovide an. improved" attachment for propellers asi set forthrahoverwhich. is very simpleiin construction, econ'omicalrincost, and; highly efficient: inuse Iirxaccordance with my invention, I provi'doeas ans. attachment to the propeller on. the? tram; thereon and? for rotation; therewith, a substana tiazlly conical member constructed: to: bore? through the fiuid imedium; as it were, an'dlltherehy overcome the compacted. body normally: misting in; thevfluidsmedium. in: front. of the-propellerhub regiom For this purpose, the conical. nose-pieceis provided: with a plurality of helicalgrooves. or channels? in its surface extending fromits for ward; apex end'all. the way bach'to its base end against which; the propeller blades: are disposed; Each groove terminates at the rear surface of-orre of the propeller blades and: receives: and guidesa stream: ot'ithe fluidmedium tangentially onto its associated blade. This breaks up the compacted flfuidfi bad y and provides fluid atthe normally inactive region of the propeller for the blad'es to bite into. Preferably, the base diameter and lengthroftlie conical nose-piece isol-theorder ot one=third the diameter of the-circle described by the outer endsor tips ofthe propeller blades asthe propeller rotates. A similar n'o'se piece structure maybeemployed to= advantagein shells or other'siinilar explosive projectiles which are protected through air or water.

The novel features that'I consider" character= is-tic-of my invention are set'forth withparticua la-rity int-he appended claims. The invention itself, however, both as toits organization and method-'ofoperation, aswell as ad'ditionalobj'ects and" advantages thereof; will best" be understood from the-f01lowingdescription, when read'incomnection with the-"accompanying drawingirr which Figure" 1- isa frontelevation of'anaeroplane propeller provided'witha nose-piece attachment in accordance withmy invention;

Figure 2 is a toppl'an' view thereof,

Figure 3-"isa 'rear' elevation thereof,

Figure-A" is an elevation of'the noserpiece. oi l igures'r-a asseerr from the base"end"thereof;-

Figure fi'is a View partly in section, ofthe stern of ashiphavingj a; propeller structure in accord; ance with'my invention, K

Figured is an enlarged; top plan view of... the propeilwstructure of Figure 5,,and

Figure 7 is a fragmentary side elevation of an explosive shell having a nose formed in accordance with my invention.

Referring more particularly to the drawing, wherein similar reference characters designate corresponding parts throughout, there is shown, in Figures 1-3, an aeroplane propeller havin a hub l which is adapted to be secured to a propeller shaft and from which radiate three suitably pitched blades 2 in known manner. Secured to the front of the propeller, as by screws 3, is a. substantially conical nose-piece 4 the base or larger end of which is disposed against the blades and the body of which extends forwardly of the propeller so that the apex end thereof is in advance of the propeller in the direction of movement of the aeroplane of which the propeller is a part. Preferably, the base end of the nose-piece 4 is formed with a central seat 5 for the reception of the hub l and with a plurality of radial slots 6 which extend outwardly from the central seat 5 each for the reception of one of the blades 2. The propeller is thus set into the base of the nosepiece 4 somewhat as best seen in Figure 2.

The nose-piece 4 is formed in its conical surface with a plurality of helical grooves or channels T which extend from the apex end to the base end thereof, there being as many grooves 1 as there are blades 2, and each groove 1 being associated with a different blade. Preferably, although not necessarily, each groove 1 is of less than a complete or full turn, as best seen in Figure 1, and preferably, also, each groove widens gradually from the apex end to the base end of the nose-piece, each groove 1 merging into its associated blade 2 at the rear surface thereof, as best seen at the center blade 2 in Figure 2.

The nose-piece 4- may be made of any suitable, non-corrosive, light weight material so that it will not add any appreciable weight to the aeroplane. As the propeller and nose-piece rotate as a unit during flight, the nose-piece bores into the air and each of the grooves 1 receives and uides to the rear surface of its associated blade 2 a stream of air. The several air streams are directed tangentially onto the rear surfaces of their respective blades by reason of the fact that each groove 1 merges thereinto as described above. In this way, the normally compacted body of air in front of the hub l and the inner portions of the blades 2 is broken up and fed to the blades which are then enabled to improve their bite in the air, since these inner portions of the blades are normally quite ineffective. I have found that, for optimum results, the base diameter and length of the nose-piece 4 should preferably be about equal and that each should preferably be of the order of one-third of the diameter of the circle described by the outer ends of the blades 2. However, these proportions may be varied to a considerable extent depending upon the size and pitch of the blades, the depth and width of the grooves l, and so on.

In Figure 5, I have shown my invention applied to a ship 8 having a propeller shaft 9 to which the propeller represented by the blades [0 is secured. Here, the nose-piece 4 has an axial bore through which the shaft 9 passes and the nose-piece is also secured to the shaft 9, the base end of the nose-piece being formed with radial seats for reception of the blades ID in a manner similar to that described above. The apex end of the nose-piece faces the stern of the ship and the helical grooves I therein extend back to the base end where each merges into the rear surface of its associated blade I0.

As the propeller Ill and its nose-piece 4 rotate, the grooves 1 direct streams of water tangentially onto the normally ineffective, inner, rear surface regions of the blades l0, thereby increasing the bite of the blades ID in the water and improving the efficiency. This construction is especially suited for electrically powered and turbine equipped ships because of the smoothness of its water bite.

In Figure 7 I have shown an explosive shell H provided with a nose I2 which is formed with a plurality of helical grooves in accordance with my invention. The nose 12 may be of conventional ogival shape and the helical grooves l therein extend from the tip or apex end of the nose to the large end thereof, each being preferably about an eighth of a turn and substantially merging into the shell casing at the large end of the nose. When a conventional shell is fired from a cannon, for example, air pressure is built up at the nose of the shell and this retards the flight of the shell more or less. However, when a shell constructed in accordance with my invention is fired, the helical grooves therein, which are turned in the same direction as the direction of rifiing, enable the shell to drill through the air and thereby overcome the air resistance. Hence, my improved shell will travel faster and will have a mor powerful impact when it strikes a target. Moreover, a shell constructed as above described is less subject to wind drift and therefore can be fired with greater accuracy.

Although I have shown and described several forms of my invention, it will undoubtedly be apparent to those skilled in the art that many other forms thereof, as well as variations in those described, are possible within the spirit of my invention. I therefore do not wish to be limited except insofar as is made necessary by the prior art and by the spirit of the appended claims.

I claim as my invention:

1. In a vehicle adapted to move through a fluid medium and including a rotar ropeller for propelling said vehicle through said medium, a nose-piece comprising a substantially conical member mounted in advance of said propeller on an axis coincident with the axis of rotation of said propeller, said member being rotatable with said propeller and having a plurality of circumferentially distributed, helical grooves in the surface thereof each extending from its apex end to its base end, the number of said grooves being equal to the number of blades in said propeller, each of said grooves being associated with and terminating at the rear face of a separate one of said blades, said grooves being adapted to receive and guide therealong to the rear of said blades streams of said medium as said propeller rotates to advance said vehicle through said medium, the base end of said nose-piece being provided with a plurality of seats, one for each of said blades, said nose-piece being disposed against said propeller with the blades thereof received in said seats, and the base end of each of said grooves being positioned to direct tangentially onto the rear surface of the blade associated therewith the stream of said medium guided thereby.

2. In a vehicle adapted to move through a fluid medium and including a rotary propeller for propelling said vehicle through said medium, said propeller including a hub and a plurality of blades radiating outwardly from said hub, a

nose-piece comprising a substantially conical member the base end of which is provided with a central seat for said hub and a plurality of blade seats extending radially outwardly from said central seat, said nose-piece being mounted in advance of and against said propeller on an axis coincident with the axis of rotation of said propeller and with said hub disposed in said central seat and a blade in each of said blade seats, said member being rotatable with said propeller and having a plurality of circumferentially distributed, helical grooves in the surface thereof each extending from its apex end to its base end, the number of said grooves being equal in number to the number of said blades in said propeller, each of said grooves being associated with and terminating at the rear face of a separate one of said blades, said grooves being adapted to receive and to guide therealong to the rear of said blades streams of said medium as said propeller rotates to advance said vehicle through said medium, the base end of each of said grooves being so positioned as to direct tangentially onto the rear surface of the blade associated therewith the stream of said medium guided thereby.

ABRAHAM WOLF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,067,410 Newnham Jan. 12, 1937 FOREIGN PATENTS Number Country Date 332,089 Great Britain July 17, 1930