US2690315A - Air vortex generator - Google Patents

Description

E. J. TODOROFF AIR VORTEX GENERATOR 2 Sheets-Sheet l SePt- Z8, 1954 E. J. ToDoRoFF AIR VORTEX GENERATOR u 2 Sheets-Sheet 2 Filed Oct. 6, 1952 4 INVENTOA fowad J 7'oaoroff Patented Sept. 28, 1954 UNITED AIR VORTEX GENERATOR Edward J. Todoroi, Portland, Greg., assignor to Iron Fireman Manufacturing Company, Portland, Oreg.

Application October 6, 1952, Serial No. 313,327 9 Claims. `(o1. 244-430) This invention relates generally to generators of vortices in air and more particularlyto the type of vortex generator which is adapted to be mounted in a desired arrangement of a desired number on the upper surface of the wing of an airplane for the purpose of generating vortices or controlled disturbances of the air slipping over the upper surface of the airplane wing. -Such controlled air vortices have been found to be advantageous in improving the operational characteristics of an airplane equipped with them. Reference is here made to U. S. Patent No. 2,558,816.

VIn the use of the vortex generator here disclosed it has been found desirable to apply heat to the generator intermittently to prevent the accumulation of ice on the wing of the plane in the vicinity of the generator. It is therefore necessary that a small insulated electric resistor heater be used to apply the required heat. In order not to disturb the aerodynamic efciency of the generator it is necessary to confine the heater within the vertical wing or blade of the generator and yet to leave the outer surface of the blade in an aerodynamically smooth condition.

The improved generator of this invention is made with a body formed of a simple and inexpensive aluminum die casting. To contain the heater a shallow rectangular cavity is sunk into the plane side of the wing of the generator and a sharp topped ridge is raised on the plane surface edging the cavity. After the heater is placed in the cavity a thin plate is laid over the heater on a shallow ledge within the sharp ridge .and a single stroke of a press is used to swage the malleable metal of the ridge solidly and smoothly over the edge of the thin plate thus permanently fixing the plate in position, sealing and protecting the heater from outside influences and leaving the surface of the generator blade aerodynamically smooth.

In mounting the heater in these generators it is the usual practice to ground one end of the heater to the blade of the generator and insulatedly bring the other end of the heater down through the stem to an insulated terminal mounted thereon. In my improved generator a cylindrical collar with internal lugs is cast on the lower end of the stem and with the terminal spaced within the collar a castable insulating resin is poured to fill the collar around the terminal. In this case as the resin solidifies the terminal is permanently and insulatedly xed to the lower end of the stem ofthe generator stem Without the necessity for using separate fastenings therefor. It is thus seen that the improved gen erator of this 'invention comprises a single die casting, an insulated heater placed in a cavity in the die casting, a thin plate covering the heat! er and held in place by swaging the die cast metal of the blade over the edge of the plate and a terminal insulatedly lmolded into an int'er. ally ribbed ycollar `on the stem of vthe die casting. A single vscrew is'used to secure the insulated terminal to an `electrical power source and another single screw is used to secure the generator to the airplane wing.

It is vseen that the principal object of this in vention is to provide an :improved vortex generator.

A second object is to reduce materially the machine time and labor required to produce `such a generator.

A third object is to make such a generator of inexpensive material.

A fourth object is to make such a generator which is simple to assemble and which can be rapidly and `permanently assembled in a minimum of time with Aa minimum of tools.

A fifth object is to make such a generator with a minimum number of parts.

I-Iow these and other objects are attained is shown in the following description referring to the attached drawings in which:

Figure 1 isa partially broken away view in front elevation of my air vortex generator.

Figure 2 kis a side sectional elevation of the device of Figure 1.

Figure 3 is a fragmentary back elevation of the body of my vortex generator viewed along lines 3-3 of Figure 2.

Figure 4 is .plan sectional elevation along lines I 4 4 of Figure 2.

Figure 5 is a fragmentary enlarged side elevation viewed along lines 5--5 of Figure l.

Figure 6 is a perspective View in partial section of my air vortex generator installed in a fragmentary section of an 'upper surface member of an airplane wing.

Figure 7 is a plan view of a fragment of an airplane wing with my air vortex generators shown installed thereon.

Figure v8 is a Vconventionalized vertical cross section of the wing of Figure '7.

Like numerals of reference indicate like parts in the several ngures of the drawing.

Referring now to the drawing my air vortex generator is seen to include a one piece die cast aluminum alloy body Il having a head l2 with an upper flat surface |3 having a wing 2| of airfoil section formed upwardly thereon. Depending from head I2 is cylindrical stem I4 with its lower end I5 hollowed out to form a collar with integral longitudinal ribs I6 therein. The intermediate section of stem I4 is cut away, as shown, to a circular segmental section to leave clearance for mounting screw carried as shown in eccentrically positioned hole I8 formed vertically through head I 2 and to give clearance for screw locking mounting nut I9. One end of nut I9 is radially multiple slit to give the nut a spring locking action on screw I'I and its other end is formed in the shape of an eccentrically bored and threaded cam.

As shown in Figure 6 a depression 42 is formed in the upper surface 4| of airplane wing 40 to receive generator head I2. Rivet 43 is set into the wing surface within the depression 42 with the round head of rivet 43 extending upward to engage head I2 in groove 20 to orient the vortex generator on wing 40.

It is seen that as stem I4 of my generator is inserted through a clearance hole in the upper surface of an airplane wing the eccentric positioning of hole IB allows nut I9 to be positioned to go through the hole. Then when the generator is seated with the underside of head I2 in mat-- ing depression 42 in the top surface of the wing 49 and with the generator oriented by seating groove 20 on mating rivet 43 in the depression, screw I'I can be turned in a right hand direction, and nut I9 will turn under the top surface of the wing until the cam head of nut I9 strikes stem I4. Further turning of screw I'I will draw nut I9 up against the underside of the top surface of the airplane wing and secure the generator in place.

Generator wing 2| is formed with a planar back surface '22 into which is sunk a rectangular depression 23 surrounded by a ledge 24 below the plane surface 22. Above the plane surface 22 and surrounding the depression 23, as shown, a ridge 25 of outwardly apexed triangular section is formed. Between depression 23 and the cut away section of stem I4 a connecting hole 26 is formed through head I2. A semicircular groove 21 is sunk longitudinally into the inner face of the circular segmental intermediate section of stem I4.

An electric terminal 28 of irregular shape is centered in collar |5 of stem I4 and a castable resin 29 is poured to form after hardening a permanent insulating setting for terminal 28 in collar I5.

To prevent interference with the proper operation of the air vortex generator during icing conditions an insulated electric resistance type heater 30' is placed in depression 23 with one uninsulated terminal (not shown) of the heater in contact with the metal into which the depression is formed and the other terminal 3| of the heater is covered with an insulating sleeve 32 and brought downwardly from depression 23, through hole 26, along groove 21, and conductingly secured to terminal 28 as shown. For heating of the generator the electric circuit through the heater is from power conductor 33 to terminal 28, to which conductor 33 is secured by screw 34, terminal wire 3|, heater 30, generator body il and the airplane wing (not shown).

The front surface 35 of generator wing 2| curved to an arc of three inch radius to form with back surface 22 the airfoil surface of wing 2|, surface 35 being joined with surface 22 along its vertical edges by arcs of about one sixtyfourth inch radius.

To secure heater 3|) in cavity 23 without impairing the aerodynamic efficiency of the surface 22 of wing 2|, body during its manufacture is placed with wing 2| located between the anvil and hammer of a press. A metal plate 36 of proper size is placed into depression 23 on ledge 24. With surface 35 resting on the similarly shaped anvil, the hammer of the press is brought down on the sharp top of ridge 25 with enough pressure to crush or swage the metal of ridge 25 into the crack around plate 36 in depression 23 and over the reduced thickness edge of plate 36 so that the metal of ridge 25 finishes the joint between depression 23 and plate 36 to make a continuous surface in the plane of surface 22.

The general theory of the use and placement of air vortex generators of the type of my invention is explained in U. S. Patent No. 2,558,816 issued July 1951 to H. Bruynes. Specic use of my generators on the wing of a B-4'7 airplane of the U. S. Air Force is illustrated and described in the November 9, 1953, issue of Aviation Week. Similarly the placement and orientation of my generators are here shown in Figures 7 and 8 where a number of my generators about one inch in height above the wing surface 4I are spaced about two inches apart along the wing span in a row a little ahead of the thickest section of the wing. A second similar row of my generators is placed on the wing about one foot back of the first row. The vertical planes 22 of the wings 2| of my generators are laterally angled about ten degrees from vertical planes normal to the leading edge of the wing with alternate generators in each row angled oppositely from their respective planes. With this arrangement as explained by Bruynes the alternately spinning air vortices formed off the tips of the alternate generators spin on axes parallel to the wing surface and normal to the leading edge of the wing and in so doing transfer energy from the main air stream over the wing to air adjacent the wing thus tending to prevent the formation of a boundary layer of air next the wing which can separate from the main air stream and thereby reduce the aerodynamic eiliciency of the wing.

Having thus explained the purpose of my invention and explained the construction and assembly of one form thereof, I claim:

1. A one piece air vortex generator body comprising a stem of generally cylindrical outline, said stem being formed with a circular head at one end, the upper side of said head forming a plane surface normal to said stem, said stem being hollow at its other end and forming a collar, said stem being cut away at one side between said head and said collar to form a connecting strut of circular segmental section, said head being formed with an upstanding wing thereon on its side opposite said stem, a crosssection of said wing in a plane normal to the axis of said stem having relatively little thickness and relatively greater width, the surface of said wing parallel to the axis of said stem comprising a plane surface having the width of said wing and a curved convex surface joined to said plane surface at the longitudinal edges of said wing, said wing being formed on its plane surface side with a rectangular depression sunk therein, said depression having a ledge formed therearound, the plane of said ledge being paral-H lel with said plane surface of said wing and between said plane surface and the bottom of said depression, said body having a straight hole therein connecting said depression below said ledge with the interior of said stem at its cut away portion.

2. A one piece air vortex generator body comprising a head having a planar upper surface and a lower surface, a cylindrical stem formed on said lower surface normal to said upper surface and a wing of airfoil section formed on said upper surface normal thereto, said stem being cut away to a circular segmental section between its ends, the lower end of said stem having a collar formed thereon, the surface of said wing comprising a plane surface and a curved surface meeting said plane surface at the longitudinal edges of said wing, said plane surface having a rectangular depression sunk therein, said depression having a ledge formed therearound intermediate its bottom and said plane surface, said body being formed with a hole therein connecting said depression below said ledge with the cut away portion of the interior of said stem.

3. The device of claim 2 including a thin cover plate for said depression, said cover plate being positioned on said ledge within said depression.

4. The combination of claim 3 characterized in that said cover plate is sealed in position on said ledge within said depression.

5. The combination of claim 4 including an insulated resistor within said depression behind said cover plate.

6. The combination of claim 2 including a conducting terminal insulatedly held within said collar of said stem.

7. The combination of claim 2 including a conducting terminal axially located within said collar, and a castable resin insulator formed between said terminal and said collar to insulate said terminal from said collar and fix said terminal in place in said collar.

8. The combination of claim 2 including a thin cover plate for said depression, said cover plate being positioned on said ledge within said depression and sealed in position to form a continuous substantially plane surface with the plane surface of said wing and said cover plate, together with a conducting terminal located axially of said collar, an insulating means adapted to secure said terminal in said collar, and an insulated resistor within said depression behind said cover plate.

9. The combination of claim 8 in which one end of said resistor is grounded to said body and the other end of said resistor extends through said hole in said body to connect with said terminal.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,971,534 Peace, Jr. Aug. 28, 1934 2,229,740 Helmore Jan. 28, 1941 2,399,370 McOrlly Apr. 30, 1946 2,418,273 Moore Apr. 1, 1947 2,462,459 Bigelow Feb. 22, 1949 OTHER REFERENCES Flight, publication April 22. 1948 (pp. 430 and 431).

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