US1767944A - Aerofoil - Google Patents

Description

June 24, 1930. H. SCHLEUSNER# A 11,767,944

AEROFOIL Filed March 14, 1929 OOOOO Patented June `24 1930 unirse STATES HENRY SCHLEUSNEB, OF GARN'EB, IOWA moron.

Application led Iarch 14, 1929.. Serial No. 847,022.

The invention relates to means for improving the load-sustaining eicieiicy of wing elements of airplanes and the like, by utilizing the kinetic energy of air movements incident L to the progress of an airplane, and air pressures developed thereby.

I am aware that passages have been formed through the wings of airplanes with a view to producin air currents for various purposes affecting the eiciency of the wings.

This is exemplified in the patent to Handley- Page, 1,353,666, and the atent to Rugg 1,084,168. It is a purpose o my invention'to present a novei constructionin which air pressures and movements are utilized to increase the vacuous condition at the upper side of the wing inan airplane. while in flight, as well as to produce .the effect over a considerable area of the wing. It'is an impor- 2@ .tant aim of my invention to utilize air com pressed in advance of the cambered forward edge of the win as ordinarilyl constructed, which compresse air under the present method moves upwardly over the wing and per-' forms no useful function in enhancing the lifting value of thecraft.

Additional objects, advantages andfean tures of invention reside in the specific construction as well as the combination and relation of parts, as may be understood from the following description and accompanying drawings, wherein Figure 1 is a cross sectional view of an airplane wing constructed in accordance with my invention.

Figure 2 is a fragmentary top view thereof.

Figure 3 is a view similar to Figure 2, showing a modification o the construction.

Figure 4 is a 'fragmentary section of a mod- 10 iiication of the slot 16, and Figure 5 is a rear View thereof.

There is illustrated a portion of aerofoil 10 which in the present instance for the most part conforms to familiar practice in thek shaping of airplane win s, and various constructional methods familiar in the art may be employed to embody the invention as disclosed. As shown, the wing may have the usual fore and aft ribs 11 covered on the under and upper sides with, suitable material 12 impervious to air excepting that a multiplicity of openings 14 are formed in the material of the upper side 13, throughout the length of the wing and for the major part of its fore and aft dimension. The forward edge of the wing from that point at which the camher eicient for lifting of the lane ceases, is inclined backward so as to acilitate an upward rush of air from this part toward the u per side of the wing. The wing thickness oi which may accord with the usual practices in wing construction or may be increased to accentuate the e'ect produced by the construction indicated. The upper surface of the wing is convergent rearwardly to the lower surface of the wing.

The wing is constructed with as much clear s ace therein as possible, and between the ribs 11 in the body of the wing, space is either clear in the fore and aft direction, or a construction employed which will obstruct such space to a minimumdegree in a fore and aft direction, so that air may move freely from adjacent the rear part of the wing toward the front edge. 'l5

At the extreme forward edge of the wing, a series of jet openings 16 (or jet slots) are formed immediately adjacent the termination of the sloping surface 15 at the .front edge of the wing before described. The so openings or slots may be edged with metal if desired, to accentuate the ejector action which ensues by reas n of the rapid movement of air thereover from in front of the wing. In the present instance, the rear ed e of the o ening 16 is shown extended slight y above t e level of the win body in order to accentuate the ejector action. It is preferable that this opening be formed in the shape of a slot extending longitudinally of the wing but vit may be interrupted at such points as necessary or required by structural limitations. The slot opens into the spacev within the wing, and under forward progress of a plane equipped with such a wing, the movement of highly compressed air with great rapidity across the upper part of the slot will result in drawing air rapidly outward therethrough, creating a vacuous condition within the wing which is communicated to the upper side of the wing by reason of the a ert-ures 14 before mentioned. In this way t e load-sustaining resultant of forces acting upon the wing is greatly increased, as may be understood.

In Figure 3 the entire upper side of the wing is shown as constructed of a more or less porous material, preferably a closely woven fabric not im regnated with dope, but open, the format1on of the back edge of the wing bein otherwise the same as before described. T is has the advantage of preventing the access of insects to the interior of the wing, or accumulation of trash therein, as will be readily understood.

In the operation of the invention as described, the air drawn outwardly from within the wing at the jet openingsrwill be projected upwardly with high momentum in a direction divergent from the wing, so that in addition to the vacuous effect produced by the drawing inward of the air at the vupper side of the wing, a further vacuous condil tion will be produced by the divergent Inovernent of the ejected air.

Construction of this character is of especial advantage in slow-moving heavy-load craft, but is also of advantage in high-'speed craft as well.

In Figures 4 and 5 there is illustrated a modification of the forward side of the jet slot 16 by which the ejector action of the device is improved. In this instance the material of the slo ing surface 15', correspending tothe sur ace 15 before described, is formed of corrugated metal with the individual grooves and ribs 17 extending in a fore-and-aft direction with respect to the aerofoil. It will be appreciated that a much magnified effect for evacuating air from within the slot 16, is produced on the air within the inner grooves of the part 15.

I claim:

1. An aerofoil having a thickened advance edge` provided with a rearwardly and upwardly inclined upper part, said foil being substantially hollow in the direction of its movement and having a jet opening immediately adjacent the upper termination of said rearwardly inclined edge whereby ejectionv of air is induced by external air, and having air inlet openings upon its upper side from closely adjacent the jet opening rearwardly thereof a substantial distance.

2. The structure of claim 1 in which said openings are covered with a porous fabric.

3. The structure of claim 1 in which said jet opening is formed with a projecting forward side of thin corrugated metal.

In testimony whereof I affix my signature.

HENRY SCHLEUSNER.

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