Патент USA US2407194код для вставки
" Sepf. 3,1946. C. 2,407,194 VOKES FILTER Filed-‘June a, 1943 , 3 Sheets-Sheet 1 1 Gecz'ZG. VG/PQS I 1/ Inventor By ’ I A tiorney Sept. 3, 1946. C. G. VOKES ' 2,“ 7,194 FILTER Filed June a, 1943 s Sheets-Sheet 2 Attorney Sept. 3,f194s.~ ' - “gm? " ' ‘FILTER 2,401,194 ' Filed June a, 1945 ' 3 ‘Sheets-Sheet s ' Inventor ' 1j I czczzalwés B Mia-[4f r ‘ - ‘ ' Attorney I Patented Sept. 3. 1946 2,407,194 ‘ ‘UNITED STATES. PATENT OFFICE 2,407,194 Cecil Gordo'n Vokes, FILTER London, ‘~ England Application Ju‘ne‘8, 1943, Serial No. 490,067 In Great Britain June 11, ‘1942 11 Claims. (01. i‘ssésa)‘ This inventionis primarily designed for ?lter ing air passing to the engine of aircraft, but it is notnecessarily con?ned thereto,lparts of the invention being of wide application where condi tions are appropriate to their use.‘ ‘ ’ rarily. For example, it may be desired to?lter the air passing to an aircraft ‘engine when‘taking oif or landing or at low altitudes but to leave the intake free while actually ?ying or when ?ying ‘ ’ _ i Fig. 3 is a fragmentary section‘on‘ the line III‘—III of Fig. 1, ‘ Y ‘ Figs. 4 and 5 are corresponding ‘views‘to Figs: It is'often desirable 'to‘cut out a filter tempo at higher altitudes. Fig.2 is‘ a similar ‘view to ‘Fig.’ 1 showing‘the“ parts in an alternative‘position,‘ p _ The present invention provides a method of ?ltering air supplied to the engine ‘of an aircraft in which the air is ‘drawn to the engine intake through ?ltering means when the aircraft is on the ground with the engine running and a pas sage for its direct entry is ‘opened under prede termined ?ying conditions, a ?ow through ‘the 1 and 2 of an alternative form, Fig. 6 is a fragmentary section on line VI-VI ‘of Fig. 4.‘ v Fig. 7 is an enlarged detail of a portionof Fig.5. As shown in Figs. 1, 2 and 3, the ?lter unit‘ lies in a scoop or other entry duct I arranged to admit air from outside the surface skin‘ of an ’ engine cowling or wing or other suitable part‘of an aircraft. The ?lter unit may include a?lter ing element 2 (for ‘example a pleated“ ?ltering screen) mounted in a frame 3 which normally ex ?ltering‘ meansrbeing simultaneously induced in tends‘at an incline across the duct ‘I. ‘ The en the reverse direction so as‘ to dislodge accumu ‘type of‘engine inlet may, for example, lated particles. ‘ try scoop (where such is used) for an u -draught ‘ have a baseportion 4 covered by a false bottom 5 which extends back nearly'to the trailing edge of the ?ltering means including a duct structure and frame 3 of the unit. The frame is pivotally a ?ltering screen,‘ an element of the ?ltering mounted at 6 and when in use lies‘at'an up means is made movable in door-like fashion, the 25 ward and forward incline as shown at Fig. '1. said element controlling air entering the struca An extension ‘I on the frame of the unit can close ture by causing it when in the one position to" or nearly close the passage 8 in the base portion pass through ?ltering means to the air intake ‘ which leads to opening‘ 9. A small leakage will: of the engine and when in another position caus normally take place past the‘extension ‘I, so that ing it to pass direct to the said air intake with a certain amount‘ ‘of dirt from the ?lter collecting out filtration’ and a small proportion to pass in front of it can pass through and emerge from‘ through the ?ltering means in reverse direction the exit 9 into the outer air. ‘ and dislodge accumulated particles. ' Distance pieces or studs I!) are formed under In a typical form a ?ltering unit is so mounted the frame 3 and when the unit is moved down to at an incline in the ?lter casing or duct that it occupy the top of the base portion, the false bot will normally be largely self-cleaning and so that tom 5 moves down‘ beneath it, as shown in‘ Fig. 2. it can be moved out of the path of the incoming The exit 9 into the outer air is arranged to help air either at will or ‘automatically under prede induce air ?ow through the element-from the termined conditions. Its control could, for ex clean side (which now faces the interior of the ample, be linked with that of a supercharger or 40 duct I) ‘so as to remove adherent dust and grit that of‘ a retractable under carriage. The pres_ from the dirty side and discharge it. Air stream ent invention has as one important part the fact separating vanesll or air straightening means may be permanently ?xed in the duct. The false that the arrangement is such as to take advan bottom will again rise into position and give- a tage of the movement of the ?lter unit to produce a reverse flow through the material of the ?lter 45 smooth path to‘ the air ?ow when the unit is re turned to working position. It might be merely screen when the ?lter is‘ cut out vand to discharge spring loadedas by springs l2 to allow‘ of its the particles or dirt thereby removed. ‘ movement‘into the base portion and automatic Other parts of the invention "are embodied in return; or it could be mechanically moved to con typical forms ‘shown upon the accompanying form to the‘ movement'of the unit. As shown,‘ drawings, the parts for which a monopoly is de operating means l3 (which may be electric,‘lhy-' sired being those "delimited'by the’ claims. ' draulic or ‘pneumatic of conventional form) on In the drawings: ’ ‘ ‘ erates a lever I 4 pivoted at l5. - Fig.‘ 1 is a sectional elevation of an‘ intake ar- ‘ _ ates a bell-crank lever l1 pivoted Accordingly, in ‘an aircraft having an engine rangement, 55 ‘the false bottom; link l9‘ and arm ZIJ‘attached 2,407,194 3 to the ?lter unit operate the latter; and a link 2| operates a ?ap 22 in the upper wall of the duct I, enabling the full area of the front of the ?ltering element to be used in the position of Fig. l. of air tends to clean the ?lter. 2. A construction as de?ned in claim 1, where in the ?lter cleaning air is directed for discharge The back of the frame is closed at 23 to seal off the aperture when the ?ap 22 is in the position shown in that ?gure. It will be noticed that the dirty side will not be able to contaminate the clean air side and 10 that the forward speed of the machinev will create a pressure at the mouth of the air scoop or duct and air will be able to blow through the. element in the reverse direction and thereby automatically clean it. 4 rection of the air therethrough during its ?ltering function, whereby such reversely directed current fully beyond the stream of air passing through the duct to the engine. 3. In an aircraft having an engine, a ?ltering assembly including a duct and a ?ltering screen, means for causing the flow of air through the duct to selectively and at will, pass through the ?ltering screen for ?ltering or, in main part, to pass through the duct free of the in?uence of the ?ltering screen, the ?ltering screen when in non ' Back ?re sometimes damages the elements and 15 ?ltering position with respect to the duct caus ing a portion of the air passing through the duct, arrangements could be made, therefore, for the unit or some part of it to depress in‘ case of a ‘ to be directed through the ?ltering screen in a direction reverse to the ?ow of air through that bad back ?re, against a spring'loading or other screen during the ?ltering function, whereby the means, so as to give free exitto the back ?re gases. This is shown as illustrated by the pivot 20 ?ltering screen is cleaned. 4. A construction as de?ned in claim 3 where ing of both the frame 3 and arms 29 on the axis in a discharge passage is provided for the clean 6 and the'use of springs 24 tohold the frame nor ing air passing in a reverse direction through the mally against the abutment on the arm. ?ltering screen to avoid in?uencing the stream Such arrangements are further examples of a of air passing through the duct to the engine. door-like use of an element carryingv the filter ing screen, and any suitable pivoted, sliding or 5. In an aircraft having an engine, a duct for supplying air under pressure to the engine, a ?l tering element mounted fOr movement with re spect to the duct, said element in one position Turning now to Figs. 4 to 6, the intake duct i has panels including ?ltering screens 2. In this 30 traversing the duct to ?lter the air passing there through and in another position being free of ?l case there are alternative intakes to the duct, tering influence on the air passing through the namely through the ?ltering screens 2 and by the rotating single or multiple door-like movement can be equally readily applied to such an element. front or scoop entry controlled byrthe movable element 30. This element takes the form of a flap with an arm 3| connected to conventional control means by link 32. It will be clear that with the ?ap 3%! closed as shown in Fig. 4, the air to be supplied to the en gine is drawn through side and bottom openings immediately beyond the ?lters 2, see Fig. 6, and through the ?lters and aligned openings in the wall of the duct l for delivery of ?ltered air to the engine. When the ?ap 36 is open, as shown in Fig. 5, the intake of the duct I initially receives the air under the pressure incident to the for ward travel of the aeroplane. Therefore, this air stream is fed directly through the duct i, free of any direct in?uence of the ?ltering elements 2. The air passing through the duct l under these conditions will in part ?nd its way laterally through the ?lters 2' incident to the eduction ef fect of the air ?owing longitudinally of the skin beyond the ?lters relative to the duct. This will cause a small portion of the airfrom the duct to be de?ected laterally of the ?lters, to pass duct, the ?ltering element in the latter position presenting its reverse ?ltering side to the air 35 passing through the ductand a discharge chan nel below and open to the ?ltering element when in non-?ltering position, whereby when the ?lter ing element isvin non-?ltering position a portion of the air ?owing through the duct is moved in 40 reverse ?ltering direction through the ?ltering element to the discharge channel. 6. A construction as de?ned in claim 5, where in the duct wall is formed with an opening to receive the ?ltering element in non-?ltering posi tion and wherein a member displaceable by the ?ltering element when moved to non-?ltering position‘ will establish communication between the duct and the discharge channel through the ?ltering element. 50 '7. A construction as de?ned in claim 5. where in means are provided to normally close the duct against the discharge element and wherein the ?ltering element when moved to non-?ltering position, displaces said closing means. 55 through the ?lters in a direction the reverse of the air movement when passing through said ?l ters for ?ltering, as when the duct intake ?ap 39 8. A construction as de?ned in claim 5, where in the ?ltering element is provided with an ex tension to partly bridge the discharge channel when the ?ltering element is in ?ltering position. 9. In an aircraft having an engine, a duct hav is closed. This reverse flow of air and pressure through the ?lters tends to clean them for the 60 ing an intake opening facing in the direction of aeroplane travel to direct air to the engine, man purpose more particularly described in connec ually operable means for closing the intake open tion with Fig. 1. ing of the duct, ?ltering elements ‘arranged im Iclaim: mediately beyond the Walls of the duct, the duct 1. In an aircraft having an engine, a duct for delivering air to the engine, ?ltering means se 65 being open to the air passing through the ?lter lectively functioning at will to ?lter the air pass ing elements, and means beyond the ?ltering ele ing through said duct to the engine or to permit ments forming ?lter inlets for air. to be passed the air passing through the duct to the engine to through the ?ltering elements and to the ‘duct, be free of ?ltration, manually controlled mech whereby when the means controlling the intake anism for said ?ltering means to cause the air of the duct is closed, the air passing through the passing through the duct to the engine to remain duct is delivered through the ?ltering inlets and un?ltered, and means to utilize a portion of the when the intake controlling means is open, the air ?owing through the duct in'un?ltered condi air passing through the duct is admitted through tion as a pressure medium to pass through‘ the such intake and passes through the duct substan~ ?ltering means in a direction reverse; to ‘the di 75 2,407,194 5 6 tially free of ?ltering in?uence from the ?ltering ing an intake opening facing in the direction of elements. the travel of the aeroplane, a skin section con forming in part to the walls ‘of the duct and ’ 10. A construction as de?ned in claim 9, where by when the intake controlling means is open, the air passing longitudinally of the ?lter inlets incident to the travel of the aeroplane will present an eduction effect through the ?lter elements to cause a portion of the air passing through the duct to ?ow in reverse direction through the ?l tering elements to clean the same. 11. In an aircraft having an engine, a duct hav , spaced from said walls, ?ltering elements ar ranged 'between the skin section and adjacent wall of the duct, the skin section and adjacent wall of the duct being formed with openings to permit air to ?ow through the ?ltering elements and into the duct, and a manually operable flap 10 for closing the intake opening of the duct at will. CECIL GORDON VOKES.