3-筛选及标引后的专利著录项目数据及专利全文us3567128a

1、United States PatentI I 3,567,12872 Inventors21 Appl. No.22 Filed45 Patented73 AssigneeGeorge R. Urquhart;Dale W.R. Lawson, Bonita; Jack H. Hilbig, Chula Vista, Calif.838,541July 2, 1969Mar.2, 1971Rohr Corporation Chula Vista, Calif.2,979,8934/1961 Meyer.239/265.29Primary ExaminerM. Henson Wood, Jr.

2、 Assistant Examiner-Michael Y. Mar Attorney,-George E. PearsonABSTRACT: Apparatus includes shroud positioned at rear of jet nozzle to surround and control gas stream. Shroud includes fixed portions defining lateral passages between them and4l 5 THRUST REVERSING APPARATUS20 Claims, 7 Drawing Figs.2 1

3、ll 5 55 u.s.cr. 239/265.29,239/265.37, 60/232, 181/33.2220- Int. ClB64c15/06一 Field ofSearch239/265.27,265.29, 265.37; 60/228, 229,232; 181/33.2226 5 References Cited UNITED STATES PATENTS2,976,68 I3/1961 Bennett et al.239/265.29pivoted doors stowed to close passages and complete shroud. When doors

4、deploy, their trailing edges meet within shroud contour to block and deflect gas laterally. Perpendicular retractable end plates at leading edges divert gas forwardly to create reverse thrust. Back pressure from reverser tends to cause back flow into ejector barrel surrounding nozzle in area upstrea

5、m of fixed portions. Retractable fences are mounted on fixed portion inner faces to intercept and redirect back flow while allowing air flow through ejector barrel in region of fixed portions. Doors are controlled to any degree of deploy ment for fully modulated thrust control in flight, particularl

6、y useful for tactical military aircraft.20PATENTEDAR 219713,567,128l 4A- ,14BIr223I,._,.22SHEET 1 OF 3202 FIG. 1INVENTOR. GEORGE R.URQUHART DALE W.R. LAWSON JACK H. HILBIGBY皂!SON JACK H. HILB1GBY 尼少ATTORNEY2 l 3,567,128THRUST REVERSING APPARATUSthe same time the leading edges swing laterally outward

7、 beyond the shroud contour. Preferablythe doors in this posi tion form a V which is slightly concave forward so that they deflect the gases laterally with a forward component.BACKGROUND OF THE INVENTION5An end plate is provided at the leading edge of each doorThis invention lies in the field of gas

8、turbine engines, more and extends inward or forward in a plane substantially perpen- commonly called jet engines, which produce reaction thrust dicular to the longitudinal axis of the door to form an abut- by ejecting a high velocity stream of gas from the exhaust noz- ment for deflecting the gas st

9、ream forwardly. It has been zle of the gas turbine. Airplanes driven btjet engines fly and 10 found that a small abutment of this type having a height of land at. much higher speeds than propeller driven aircraft.- only a few inches has an extremely high diverting effect which!h ir high_ la ding spe

10、 d p ts a g eat burde - on t e. heel apparently results from the fact that the abrupt change ofbrakes and of course they do not have propellers which are direction of the gas striking the abutment builds up a gaseous readily reversible to produce reverse thrust. Therefore it is shield which is effec

11、tively an extension of the height of the endnecessary to provide apparatus to reverse the gas stream to ac- 15 complish this result.plate. In any event, tests shown that the reverse thrust ob-It is also highly desirable to be able to control effecti;v,.e0 tained with this construction can exceed 60

12、percent of the thrust in flight. This is particularly so in the case of tactical maximum forward thrust of the engine through pressure ratios military airplanes, which may be required to decelerate ranging from 1.3 to 4.0. Since no reverse thrust can be rapidlyin combat aneuvers orlimit their speed

13、in steep dives 20 produced ?Y any po tion_ of a door xtending beyond an_ ab t- in.bombing operations. Conventionally, speed brakes are usedment on the door, this tip mounted arrangement permits thefor this purpose.use of a door of minimum length. Preferably the end plate isVarious types of thrust re

14、versers have been in use for many retractable into the thickness of the door in stowed position in years, primarily to reduce landing run although some have order not to project inwardly into the path of the gas stream in been successfully used in flight to reduce forward speed more 25 normal operat

15、ion.rapidly than by throttling the engine. All of them utilize a basicBecause the doors are mounted in openings in the shroud, principle of blocking the rearward flow of the exhaust gas the support structures serve as shields between the doors to stre m and diverti g it lat ally and substantially fo

16、rward_ly tpreve t the escape of large quantities of gas laterally withoutproduce reverse thrust. One common type uses a pair of any forward component, which is a very serious defect of thedeflectors which meet externally behind the nozzle to divert 30 external target type mentioned above. Also the d

17、oors arethe stream laterally in opposite directions, usually with a for- ward component. Another similar type has doors mountedwithin the nozzle to block flow, lateral openings in the noz. zle, and doors or deflectors which normally cover these openi ngs,mounted to solid structure rather than on elo

18、ngate linkages which are vulnerable to the high vibration forces induced by the gas stream.but which may be swung outward to uncover the openings and 35 When the engine is of the type which includes an ejector direct the diverted streams laterally and forwardly. In another barrel surrounding the noz

19、zle, the shroud is preferably formed type, doors within the nozzle may be moved to block flow, and as an integrn part of the_ ejector_barrel. When_the reverser is incascade passages are uncovered in the sidewalls to allow theuse, the deflecting action of the doors and the end plates gas to issue lat

20、erally and forwardly._ produces a slight back pressure. The support structures All of these systems work reasonably well but they have 40 prevent the gas from flowing radially outward- ii-. the areas they various drawbacks. They are difficult to modulate and nor-cover. The result of these factors is

21、 a force tending to produce mally are used only in fully deployed position. The externala back flow of exhaust gas into the ejector barrel in the areas t? get.t7pe, with. _deflectors behin the ?,0z le, ;equire :0n-adjacent to the support structures. Thiswould hamper enginesiderable supporting struct

22、ure and usually has larger deflec- 45 cooling flow and possibly the gases could reach a point oftors than is desirable. Also, it is difficult to arrange a pivotal mounting which will make them fail-safe; i.e., mounted sothat in the event the actuating mechanism fails they will be urged by the gas st

23、ream toward stowed position. The otherentry into the engine compartment. This undesirable effect is prevented by the provision of a fence mounted on the inner surface of each support structure which extends across at leasttypes have rather complicated mechanism, at least part of the major part of th

24、e width of the structure. The fences inter-which is always subjected to the hot gas stream and thus is a 50 cept the back flow and force the gas to exit laterally with thepossible source of trouble or failure. Generally, their efficien- main body of the stream. They are mounted in the ejector bar- c

25、y or percentage of forward thrust available in reverse thrust is rel downstream a sufficient distance to provide an adequate below 50 percent.path for the normal flow of air, and may be fixed or retracta-SUMMARY OF THE INVENTION55 ble.One of the principal advantages of the construction of thisThe pr

26、esent invention provides superior performance and is invention is that reversal can be used instead of throttling in adaptable to all types of engines. The deflectors or doors are military maneuvers, particularly steep dives. Ordinarily in smaller than those of some previous systems while producing

27、a such circumstances the procedure includes cutting the engine higher thrust reversal factor, and there.are a relatively smaH 60 to flight idle while reduced speed is attained by speed brakesnumber of parts which are rugged and dependable. Generally or the like. It is then essential to return to ful

28、l power as quickly state?,_ in its gen_e_ri !O the appat tus includes_ a s roud as possible. Tests have shown that various engines iequire which is mounted behind the nozzle exit to surround and con- from 4 to 14 seconds to regain full power. With the present trol the gas stream. The shroud has one

29、or more fixed portionsreverser, the engine may be run at full throttle while produc-defining lateral openings for the diverted gas stream and a 65 ing full reverse thrust, which is more effective than idling.door for each opening.The doors are pivotally mounted on the fixed portions which are rearwa

30、rdly extending support structures, the pivotal connections being intermediate the fore-and-aft length of the doors and openings. In stowed position, each door mates with 70When the reverser is stowed the engine forward thrust full power is available in less than one second.The shroud portion of the

31、ejector barrel, including the doors, may take any suitable shape depending on the particu-its respective ope;ing to definethe shroud as an elongate con- lar requirements of the engine with which it is used. However,duit which is substantially axially aligned with the axis of the it is normally gener

32、ally cylindrical and the doors have arcuate nozzle. When the doors are fully deployed, their trailing edges cross sections which are concave inward, so that the doors swing in to meet at the axis of the nozzle within the shroud present a troughlike shape for guiding the deflected or con tour and sub

33、stantially block the path o 八 he gas stream. At 75 diverted gas stream.4 3 3,567,128BRIEF DESCRIPTION OF THE DRAWINGSends 30 swing laterally outward of the shroud contour.Various other advantages and features of novelty willPreferably the doors are so dimensioned and mounted that;:.:_.;.:each door i

34、s inclined forwardly about 15when deployed as ii-become apparent as the description proceeds in conjunction lustrated in FIG. 3, and the doors thus form a V concave for- with the accompanying drawings, in which: 5 ward so that the diverted gas streams have a forward com-prwithFIG. 1 is a pictorial v

35、iew of the tail portion of an aircraftponent and produce a certain amount ofreverse thrust.ovided wi_th thr st reve in_g 旦pparatus in cc_ordance;_ :_:The major part of the thrust reversal in accomplished by thethe present invention, panels being cut away in the drawing so that part of an actuating m

36、echanism can be shown and thrust- :.;:;provision of end plates 32 mounted at the forward faces 34 ofthe doors (which faces are set back a short distance from thereversing doors being illustrated in a deployed position Iopanels that form the outer surfaces of the doors). These end thereof;:.plates ar

37、e thin and preferably flat and, when the doors areFIG. 2 is a rear elevation of the tail portion of the same a 订 craft;: :J ment very forcefully diverts the gas stream forwardly toFIG. 3 is a longitudinal section of one of the two thrustdeployed, they project inwardly or forwardly from the inner sur

38、faces of the doors in a plane which is substantially perpen- dicular to the longitudinal axis of the door. This abrupt abut-reversing installations ofthe aforesaid aircraft, taken alongthe l 5.planes represented by line 3-3 in FIG. 2 and in the directionproduce a very high reverse thrust component.

39、It has been indicated therein;- - -found that the diversion effect is considerably greater thanFIGS. 4 6 are enlarged, fragmentary pictorial views of,.: :would be expected from an abutment of only a few inches atcomponents included in each thrust reversing installation ofthe aircraft; and20most, and

40、 it is believed that this results from the fact that theFIG. 7 illustrates a second embodiment of the inventi;Ao_n.- diverted stream forms a gaseous wall which greatly increasesthe effective height of the end plate itself. An example of thisDESCRIPTION OF PREFERRED EMBODIMENTSeffectiveness is a typi

41、cal test run with an engine having an exhaust nozzle diameter of about 15 inches. The end plate height he th_rust r v_e sing apparatu ?fthis i vention_ma_y be sed 25 was varied from about 7 to 12 percent of the nozzle diameter with engines which are mounted in naceHes attached to _win_gs - or about

42、l to 2 inches. With this very smallabutment height or to fus lage sides, or wi_th engines which are buried in thethe reverse thrust developed was from about 50 percent- towings or fuselage or elsewhere, and operates in the same way over 60 percent of the full-forward thrust of the engine.in any inst

43、allation. It is shown in FIG. 1 in conjunction withThe arrangement described above is far more effective than fuselage 10 which encloses two engines (not shown) and 30 the externaf target type in which a pair of deflectors are which has a vertical stabilizer 12 mounted thereon. The rear-abutted behi

44、nd an open tailpipe. One reason for this is the fact most portion of the fuselage is formed with a pair of ejectorthat the support structures prevent radial outward flow into barrels 14A, 148 which respectively surround the nozzle 16the area where the doors do not guide the stream. Con- (see FIGS. 2

45、 and 3) of the aforesaid engines to form a path ofsequently, all of the gas is given the necessary forward com- annular cross section 17 for the flow of air for cooling and 35 ponent which produces the desired reverse thrust. The present thrust augmenting purposes, this air flow being represented by

46、apparatus is also desirable because of its fail-safe charac arrows 18 in FIG. 3.teristics. The pivot location is so chosen that the gas forces on As illustrated in FIGS. 1 and 2, each ejector barrel ter-the total door always exert a stowing moment. ln the event of minates at its aft end in a shroud

47、which comprises at least onefailure of the actuating mechanism, the doors will be urgedand usually two or more fixed portions 20, and at least two 40 toward stowed position and will at least trail sufficiently so movable portions which are generally designated 22 andthat normal flight may be continu

48、ed. Without this protectivewhich cooperate in their stowed positions to define the shroudfeature the pilot must promptly turn off the effected engine.as an elongate conduit which is substantially axially alignedThe construction and operation described above may be ap-with the axis of the nozzle. The

49、 fixed portions are firmly at-. _ plied whether the engine is equipped with an ejector barrel or tached to the ejector barrel by bolts or the hke and may m- 45 simply wnh a nacelle covering. In the case where an ejectorelude a structural mounting ring to unitize them and facilitatebarrel is present,

50、 as illustrated in FIG. 3, a problem arises attachment to the ejector barrel.because the combination of the back pressure produced byPortions 20, which may be termed support structures, arethe doors and end plates and the obstruction to radial outward spaced evenly around the periphery of the shroud

51、, which is rn flow in the area of the support structures tends to produce a usually substantially cylindrical in cross section or slightly 50 bacJku flow of exhaust gas into the ejector barrel in the area up-conical although it may take any form which fits the engine stream of the support structures

52、. This back flow interferes requirements. ln the form shown, they are arranged in op- with the cooling action and in some cases could reach a point posed spaced relation on opposite sides of a diametral of entry into the turbine which is very undesirable.reference plane which includes the axis of th

53、e nozzle. The sup-,This problem is overcome by the use of barrier fence means 55port structures 20 define between them openings 24 for the - or a fence 36 mounted to the inner wall of each supportexit of exhaust gas 25 and air 18 during thrust reversal, andstructure and extending generally perpendic

54、ularly to the axis portions 22, which may be termed blocker doors, are shapedof the nozzle. The fence extends across at least the major part and dimensioned to form accurate closures for openings 24of the width of the support structure 20 and has a height of the during normal operation.60 order of I

55、O percent of the nozzle diameter although it may The doors are pivotally mounted to the support structures,vary from about 7 percent to more than 12 percent depending as indicated at 26 in FIGS. 2 and 3, at points intermediate theon design considerations. The fence is a thin plate generally ends of the side margins of the doors and