Патент USA US2403749код для вставки
‘July-9,’ 1946. 2,403,749‘ w. B. O’NEA‘L-v FUEL TANK VENT 2_ YSheetS-SheefuIl-II Filed May 17, £945 MEDQh. - WILLIAM INVENTOR. B. O'NEAL. 1 July 9, 1946. 2,403,749 w. B. IO’NEAL FUEL TANk-VENT ‘ 2 Sheets-Sheet 2 ‘Filed. May 17, 1945 N , mvmmz WILLIAM BY "74 _ B. ATTO O'NEALI EY " Patented July 9, 107946 A 2,403,749 UNITED 'STATES.,, f oF'FicE; rum. I 2,403,?49 TANK VENT . William 13.0mm‘, EllicottCity, :Md., assignor to ' The GlennL. Martin Company,.Middle River, ~ 'Md., a corporation of Maryland ‘ ' . ‘Application ‘May r1, 1943,}Serial No. 487,255 ‘ “.1, 244-435) 2 I Claims. pedient to extend the'vent tube out the under side Thisinvention relates to a vent for fuel stor of the wing, in'the direction 'ofthe motion of. the airplane to maintain a positive pressure in'the age tanks On any vehicle, but is particularly adapted for venting the fuel storage tankson . aircraft. , ~ _ _ 1 ' cell.‘v 1With this arrangemenhit is obviousthat the; pressure in?the fueltank ,may'build up to an _ It has always been a problem to provide proper . undesirable maximum pressure depending on the vents for the fuel tanks of aircraft. These vents maximumspeed of‘the plane, It is also apparent serve several useful purposes, fundamentally, thatgsuchv avent, undercertain weather conditions they let air into the tanks as the fuel is withdrawn easily become clogged with ice. 7 l ,, ‘ > , . by the fuel pumps of the engine. Due to the speed 10 would The primary;_;object1,ofy the invention herein of the aircraft, it is usual :to have the terminal disclosed is to provide va vent for the‘fuel con of the vent forwardly directed, to take advantage tainer; of avvehicle which will maintain a prede of the air speed to [maintain the air space» above termined positive pressure inthe fuel container. the fuel in the tanks, at a slightly positive pres sure with respect to the atmosphere. Thiswcon 1 - vA; furthertobject of the invention is the pro dition reduces the vaporization of the fuel, par 16 vision ofa fuel cell vent system in, which a pre determined -_li_mited pressure ‘may be] maintained. A furtheriobject of theinvention is the pro visionrof a'vforwardly directed vent line that will ticularly at high. altitudes. The great disadvan-v tage, which is overcomeby this invention, is that in the usual forwardly directed vent, there is no control over the amount of pressure in the tank -» and such vents very readily become clogged by ice formations. - maintain itself ice-free underladverse weather conditions.’ _ r - 3 - I v Further and other objects will become apparent .1 fromthe description of the, accompanying draw-v It has long been the practice in aircraft to ings which form a part'of this disclosure andvin utilize the wing space for fuel storage by inserting» ? * which like numerals refer to like parts. 1 r ?exible bags or cells in the cavities in the wings, drawings: ~ ; g I r which contain the liquid fuel, the walls of the 35 Inthe Figure l is’ asectionalyview of an airplane wing cavity acting as retaining structure. These cells are so formed that the external dimension of'the cell are substantially equal to the internaldi mensions of the cavity so that when the cells are loosely placed in the cavity, the pressure load of 3 the liquid is transmitted to the retaining struc ture. The cell acts only as a container for the liquid. A more detailed description of this fuel storage system can be obtained from the Gray 35 and Zivi Patent No. 2,102,590. In'the ?exible cell installation, it is usual to attach the cell at a few points around the top of the cell to the walls of the retaining structure to prevent complete collapse of the cell when empty. It is necessary, in installation of this type, to pro vide a vent or afford a means of open communi cation with the atmosphere because, as the gaso line is withdrawn from thecell, two undesirable things may take place. If not vented properly, the cell may collapse due to atmospheric pres sure and place an undesirable strain on the ?t tings and attaching means of the cell to the cavity walls, or the pressure in the space above the gaso line may be lowered to a point where undesirable showing the invention’. , 7 ~ ' ‘ 1 Figure Z-is .a perspective iiiew of the vent at tached to the vehicle.’ 1 ; I _ Figures 3 and flare plan and-elevational views of the vent. ' In the drawings Figure 1 shows a typical wing section and fuel storage cell installation. Fuel is stored in the ?exible fuel container I, retained in a cavity formed by the skin 2, spars 3 and 4, and transverse bulkheads 5. These cells act merely as containers for the liquid and being flexible, transmit the ?uid pressure load to the retaining structure. Cells for this purpose are generally 40 formed so that their exterior dimensions are sub stantially equal to the interior dimensions of the cavity adapted to receive them so that no stress is placed on the cell wall structure. It is customary to support the tops of the cells at a few points around the perimeter to prevent complete col lapse when the cells are empty. A vent line 6 extends from a ?tting 1 ad jacent the top of the cell installation to the vent structure shown in Figures 2, 3, and 4. '50 This vent structure comprises a curved tube 8 7' vaporizing of the gasoline may take place. having the open end thereof extending in the The above problems are solved by extending a direction of ?ight. The streamlined surface of ‘pipe line from somewhere outside the airplane to revolution 9 is positioned in front of and co a point adjacent the top of the cell to act as a vent. axially withthe open end of tube 8. The rear From pressure considerations of the airfoil in 55 portion ll) of the streamlined body is truncated which the cell is usually mounted, it is more ex-' 3 2,403,749 4 to a diameter substantially equal to the interior diameter of tube 8. Both tube 8 and stream might cause the icing-up of the entrance to the tube. Ice particles will be de?ected by direct impact and liquid particles, entrained in the air, will .be removed from the air stream before reach_ ing the open end of the tube by centrifugal lined body i9 are supported from a mounting plate I I. This structure is more easily fabricated by means of two similar stampings shown as I 2 and I3 in which both the streamlined shell, the tube, and a supporting structure are formed force as the air stream flows around the curved surface of the streamlined body. as a single stamping and later welded together This vent structure may ‘be located on the along the parting line [4. The assembly ‘is sub side of ‘the wing for wing tanks or any sequently welded to the mounting plate ‘I I." The 10 ‘under whereon the fuselage or body of any vehicle space between tube 8 and body 9 is milled out , _ for other tanks. to a predetermined width depending upon the ‘ It is to be understood that certain changes, pressure desired in the vent line and cell, modi?cations and substitutions can It is obvious that without body a, the forward; '“' alterations, be made without departing from the spirit and 1y directed attitude of tube ‘8, would receive ‘airscope of'the appended claims. of a pressure head equal to the ‘velocityof-‘the ‘I ‘claim as ‘my invention: vehicle and this abnormal air pressure would '1. In combination in an aircraft, a ?exible be transmitted to the interior of the .fuelistorg' ~ age cell. A slight positive pressure above the. gasoline in the cell is necessary and‘ desirable.‘ '20 It is necessary, to permit the flow of gasoline from the storage .cell, was 'it is required (‘by the engine. It is ‘desirable, to ‘prevent the collapse ,non-self-supporting fuel containing cell mounted in saidaircraft, a vent mounted on the external surfaceof said aircraft, a vent line extending from said vent to said cell, said vent comprising ay'forwa'r'dly directed open-ended tube, a stream linedbody having a surface of revolution posi of . the :cell :when empty: or-lnear ‘empty. Too great a pressure is- as objectionable as too little 25 tioned in ‘front of and coaxial with said tube, the trailing end of said streamlined body trun pressure in‘the .cell. . Therefore, due itorthe prac cated to a diameter substantially equal to the diameter of said tube, said truncated end of said 'body’being spaced from the open end of said :tube, ‘said spacing being such vas to regulate the amount of air ?owing over the body that will tical certainty thatthe open end of tube 8 will become clogged ‘with ice, and the fact ‘that the pressure of the-air >is 'directlyldepending upon the velocity of the vehicle, ~'-the 'open-endedifor wardly direct tube is obviously:unsatisfactory. By placing the streamlined vbody _9 in the posi tion shown with respect -"to -'the ‘tube »8, I'cert-ain desired resultsarelobtained. -It~will'~be seen'that enter the open end of said tube. 2. ‘In combination in an aircraft, a ?exible non-self-supporting fuel containing cell mounted due to its- streamlined shape, the’ air- will ?ow 35 in said aircraft, an anti-icing vent mounted on the external surface of said aircraft, a vent line extending from said vent to said cell, said vent The tapered trailing edge of body 9 can be comprising a‘ forwardly directed open-ended truncated so that ‘portion l-IJ with-respect-t'o-the tube, a streamlined body having ‘a ‘surface of open end of tube-dis of such diameterthat revolution positioned in front of and coaxial any desired ?ow, ofair intotube 8 may be-maine 40 with said tube, the forward end of ‘said ‘body tained. In other words, the open endof the -' curving to a maximum diameter greater than the tube maybe arranged'with respect to the trun diameter of said forwardly directed tube, .the cated end of the-‘streamlined body ‘so that‘it trailing end of said ‘streamlined body truncated skims off a layer of airvunder oa-certa-in'vvelocity a diameter substantially equal‘ to the diameter head to any desired thickness, thereby 1con 45 to of said tube, ‘said truncated end of ‘said body trolling the volume of air. The maximum speed being spaced from the open end of ‘said tube, of the plane being known, the spacing and ‘rel over the body toward vthe opening in 'tube~8. I said‘spacing being'such as‘to'regulate the amount ative diameter can be such that the maximum desired pressure in the cell‘wvill be maintained. It will be noted that the streamlined body-acts to as a deflector for ice particles or'moisture'that " of air’ flowing ‘over the'body that will‘enter the open“ end of said tube. ' " ' ' WILLIAM B. O’NEAL.