Патент USA US2404743код для вставки
July 23, 1946. 2,404,743 R. PRAUSE DEVICE FOR ADJUSTING THE PITCH OF‘ AIR PROPELLERS Filed Oct. 22, 1940 s Sheets-Sheet 1 15 18 I v /_ /- /,/ /‘ 14 " ~ /I) J \ 12 10 v , Q’ - 32 _3_*___ \ \ / I I > - )0 I ‘July 23, 1946. R_ pRAusE ' 7 2,404,743 DEVICE FOR ADJUSTING THE PITCH OF AIR PROPELLERS Filed Oct. 22, 1940 » [gin 5 Sheéts-Sheet 2 'nz - ‘ > | ,4 a 1o 14 0 32 3 37 33 a . H92. 31/ 7 a ' ‘.23 6 . 5 a9 ' 9 _ ' _____ ‘ __ - -| _____ -_ =__- -srezssz; - m ! r 1 [r ‘ j 3 I ‘ J ‘OJ; Y 23066»? 73rd use July 23,1946. IR. PRAUSE ’ > 2,404,743 DEVICE FOR ADJUSTING THE PITCH OF ‘AIR PROPELLEBS Filed 001:. 22, 1940 . 5 Sheets-Sheet 3 Inventor‘: fiber 7“ Pl'a, ‘Q66 Patented July 23, 1946 ' 2,404,743 “UNIT-JED STAT-ES PATENT OFFICE‘ '_ ‘:Ro‘bert Prause, Augsburg. Germany; vested in the lAlien“"Property Custodian Application October 22,1940, Serial-No.“36\2;2‘79 .In?ermany June. 10, .1938 _> ‘l‘lllaim. ,1 (Cl. 170-463) .2 _ This invention relates‘ to 'apropeller adjustment device. _ . Certain devices for the‘adjustment of the pitch of air propellers while in operation areknown in which the blade adjustment is carried out by “ come apparent from ‘a considerationottheyan nexed drawings and the following description, the inventionconsists not only inthe structures hereinpointe‘d outl‘and illustrated bythe idraw- ' ings, but includes .furtl-rer r-structure-s coming within the scope of the claim. 7 r _ . means of a bushing'or sleeve mounted to slide on The character of the invention. however, .may the propeller shaft. The sliding‘ operation , of be best understood by reference .to certainofsits said bushing (or sleeve is effected by means of an structural forms, .as illustrated .by, the‘naccome adjusting lever or traverse which surrounds the _ V '_ V l ‘- ‘ bushing and at one end is mounted to swing on 10 panying drawings in which: Fig. 1 shows a schematic, perspective-view-jof a stationary point of the aeroplanethe other the essential parts of an ‘adjustment ,device'hav end being connected by a simple link with an adjustable system ‘ofjrods leading to’the pilot’s seat. The sliding ‘motion received‘by the sliding bushing is transferred ‘to the base of the propel 15 ler blades, which are turnably mounted, by means of jointed levers. ‘Although this known ‘device enjoys the advantage of great simplicity as com pared with other designs of‘ blade adjustment, it ing the invention applied thereto.‘ ‘ ' w , 1 Fig. 2is a side elevation, partly in sec1ion,..of the same adjustment device. , i Fig. 3 is a plan view,;partly in section, online III-—III of *Fig. '2. g j ‘ Fig. 4 is a section accordingto line IV-.-IV of Fig. 2. ‘ . . found that the suspension arrangement which Fig. 571s a-section-similar.toFig. 4, but shoW~ ing another design-of the .gimbal mountingof allows the adjustment traverse surrounding the the adjustment device. sliding bushing'to swing around one axis only, or As here shown, I provide means between the stationary‘points for ‘the suspension of the de vice ‘and the sliding bushing or sleeve for gp?r mitting a Cardan motion, ‘or relative swinging has not proven useful in actual practice. ‘It was 20 around two‘ parallel axes, showed considerable wear ‘and tear, especially at the‘ sliding bushing, ‘1 after only a few ‘flying hours. ' It is an importantobj'ect of the present inven- , tion to'provide means in the‘ adjustment device for avoiding such premature wear. In the course of the ‘investigations leading'to the present in vention it has been found that‘this defect of-the known device'is 'mostlytdue to thefact that .the propeller shaft and ‘the axis'for the swing adjust; ment of the traverse while in operation deviate imperceptibly from ‘their ‘original position at , right angles to each other. Such deviation is brought about ‘by certain forces during the ?ight. The relatively rigid connection of the adjustment ‘ of the parts aroundrtWo axes at right anglesto each other. The traverse lever for adju'sting'the sliding ‘bushing is suitably designed as‘ a ring surrounding the .bushing. Said ring at one “end is mounted at a stationary ‘point ‘of the aeroe plane, preferably by means of .a link or swing member, so as to. move around two perpendicular axes, :while at .its :other end .the adjustment spindle is connected, movable, also around two perpendicular axes, ‘by‘meansof the spin‘dlenut. The annular ‘traverse lever Whichsu-rroundsi-the sliding bushing and the propeller shaft‘is con~ traverse on one side and the play of the parts'beé longing to‘ the adjustment device on the otherside tend to cause a sort of wabbling motion of‘the traverse ring, or of the sliding bushing, causing the latter to deteriorate and to wear out "rap nected with the sleeve'eifecting the blade adjust idly, since the adjustment traverse owing to its ball bearing‘by means of trunnions. rigid connection cannot give ‘way "to the oscillat- - ing movement. Moreover, ‘the sliding motion of the adjustment sleeve causes an edgewise pres sure stress which, in ‘cooperation with the wabbling motion, tends to wear out the sliding bushing. ‘ "Therefore, the present "invention has for its object to provide a constructionof a-propeller ‘ ment by means .of a ball bearing .whichlprefer ably ‘is of a type to receiveaxial forces. ‘The traverse ‘ring is swingably connected iwith :the outeruring, ‘or with thesupporting ,ring "for the ‘By arranging the ‘component parts‘or elements, as above described, ‘which. make possible a ‘gim bal movement of the adjustment sleeve, great improvement in the stress conditions tofithenid justment device has "been obtained and, ‘as ;:a consequence, ‘the number of "flying ahonrs “could be considerably increased. ‘Preferably, andxas here shown, I may ‘obtain a further improvement of ‘the ‘stress conditions by manufacturing. the adjustment sleeve and/or -a sliding rbushing of the parts without any substantial wear. With these and further objects in view, :as may be 55 mounted on the i‘ propeller shaft "from‘synthet'ic adjusting *device which permits wabbling-mot'ion 2,404,743 3 4 material, especially synthetic resin with tex . 22 at the right-hand end, Fig. 3, of the spindle tile inserts or admixtures. This material may consist of various kinds of synthetic compressed material such as phenol-aldehyde condensation products which are known as “Bakelite.” Also 2| permits rotation thereof as well as swinging through a certain angle, but prevents axial movement of the spindle which carries a nut 23 mounted to swing in all directions, with respect to the traverse ring I4, at H; bymeans of a self aligning ball bearing 24.1 ,The nutf23 is prevent resin impregnated fabrics, hard wood and hard paper of all ‘sorts as well as any pressing mate rial from' paper and textiles in‘ layers in‘ non‘ ed from turning by an arm 25 and a bolt 26. laminated form may be used after having been ’treated with a suitable binding substance. The The nut 23 is also prevented from sliding with relation to the traverse ring I4 by means of the sliding bushing mounted on thepropeller shaft » threaded rings "21 and 28, the ?rst ring being the can sleeve be made moving of such thereon synthetic can be material, madeof metal. while;a screwed together with the traverse ring I4 and By manufacturing the bushing and/or lsleeve ' . serving as a frame for the ball bearing 24, while .thesecond ring is mounted on the other side of from any of the synthetic materials mentioned, ' a longer life of the device is’obtained than would. '; y ,,the ball bearing 24 and screwed together with the‘ nut 23.‘ 'The' free end of the spindle 2I is be the case if it would be manufactured “ex clusively from metal or metal alloys. vEven if ., provided with a safety-and-stop ring 29. Dis . placed by 90° in relation to the suspension points metal alloys of the highest abrasion resistance I and II. the traverse ring I4 carries 'tr'unnlons 30 and 3| (Fig. 4), betweenwhich rests the sup porting ring 32'for the ball bearing 33. The in ner ring 34 of the bearing 33 ‘is mounted on ‘the are used in the manufacture of said bushing and » sleeve, undesirable quick wear have been-found to be unavoidable. Applying‘ the experience so far made‘with slide bearings of arti?cial‘mate rial, it was surprising to ?nd out that by using synthetic vmaterial ‘in 'the'device, according to the 25 ' invention, the dangerous stresses at the edges of, the‘ sleevecould be met. '> 7 Referring now'to the drawings in greater de , tail, ‘and ?rst‘to Figs. l'toi‘l, it "will-be seen that adjustment sleeve I3, being forced against the stop 36 of the adjustment ring II] by Ineansofa threaded ring 35.1 Another threaded :;rin'g-.3l which is screwed ‘intothe supporting v‘ri'ng'f'32 helps to hold. the outer ring of the ball bean ing within the supporting ring. .A key 38;.en-1 gaging in a suitably dimensioned slot of: the slid~ the propeller blades land 2_ of a two blade pro peller are tu'rnably mounted‘ in the propeller hub ing bushing 8 prevents the adjustment sleeve In 3. from turning with relation 170717118 bushingpB. ‘I _ Instead of the Cardan-like‘connection by pro— The hub '3 is coupled. with a hollow propeller shaft 4 by means of 'two mutually engaged vision of self-aligning ball bearingshbetweenthe held together by a threaded member 6. The 35 traverse. ring‘ I4 and the guide member ~-I5Tas well as the ‘spindle 2i, the traverse ring .can also propeller shaft 4 at its other end is shapedv to'?t be connected Cardan-like or gimbal-fashion with thedi?erent motor connections and is connect toothed portionsindicated at 5, both parts being the adjustment sleeve or with the supporting ,ed with the motor ‘shaft by bolts ‘I. An anti ring 32 of the ball bearing 33 by‘means'of‘an friction bushing or sleeve 8 consisting of "syn thetic resin on a‘ phenol-aldehyde basis with 40 auxiliary ring 32* (Fig. 5). This ring. 32" can " textile admixtures is fastened on the hollow shaft be swung around the trunnions 3t! and 3|, while 4 by means of screw bolts 9, for reception of an adjustment sleeve I0 mounted to slide on the bushing 8, and provided with eyelets II which have the guide members I2 jointed to them for ‘ connection with adjustment levers I3 which are rigidly screwed to the base of the‘ propeller blades by means of their female thread so‘ that any ‘swinging of, the levers I3 will also cause the. pro- r peller' blades land 2 to be turned correspond ingly. The adjustment sleeve I 0 is surrounded the supporting ring 32 can be swung perpendicg I ularly thereto around- the t_ runnions‘ 30’ and‘ 3_I' g of the ring 32’. _, 3- - '- V_ - 1 When in operation the. propeller ‘revolves around the propeller .or motor axis III->—III jointly with the hollow shaft 4,.the antifriction bushing 8 mounted‘ thereon, the adjustment sleeve I0 and the inner ring 34 of the ball bear; ing 33, with relation to the outer/ring of the ball bearing and the remaining parts of the adjust bythe ring-shaped adjustment traverse lever I4 ment traverse. 'The position or pitch of the pro which at its extreme opposite ends I and II is I9 and a trunnion I8 as shown in Figs. '3 and 4. peller blades is dependent upon the axial posi~ tion of the adjustment sleeve I0, and conse quently upon the position of. the nut 23 on the spindle 2| which can be turned in the self-align ing ball bearing 22 by means of a Cardan drive 40, as indicated by the broken line on Fig. 3.’ Rotation of the spindle 2I causes the nut 23 to be moved axially and, since the latter is ?xed immovably in the traverse ring I4, it is bound to take along the traverse ring swinging same around the trunnionIS of the suspension point I. Through this swing movementthe adjustment, The other end of the rod I5 is connected at I6 to a ?xed bracket which is ‘rigidly attached to some part of the areoplane such as the motor for pro sleeve I0 is moved on the bushing 8 by means of the ball bearing 33 adapted to carry an. axial load. This movement is transferred by way of connected by means of a ‘Cardan or universal joint to connecting members which in turn are suspended at stationary points of the ‘aeroplane. The connection at II is adjustable in such a Way ' that‘ the traverse ring during’the adjustment can be swungaround the‘ point I. The suspension of the traverse ring I4 at I is movable but not adjustable. 'The traverse ring I4 is connected to a fork-shaped end I‘! of a guide member‘ or rod I5 by means of a self-aligning ball bearing pelling the plane. Said bearing! 9 is mounted in the eye 20 of the traverse ring I4 so that the traverse ring can be turned around two perpen dicular axes with'respect to the guide member I5. The traverse ring I4 can be swung around the suspension at I by means of the adjustment spindle» 2I connected at II, thus producingthe adjusting motion. A self-aligning ball bearing the guide members I2 to-the adjusting levers I3 which in turn take along _ the propeller blades and cause them to turn in their ‘bearings. Owing to the Cardan-like' or gimbal'mo'unt ing of the traverse ring by means of self-aligning ball bearings, all parts'of the adjustment device can follow up any possible “skewing”- which might emanate from the forces taking effectduiu 2,404,743 5 ing the ?ight, so that premature wear and tear of the adjustment sleeve ID or the bushing 8, will be largely avoided. By manufacturing the sliding bushing 8 from synthetic material it is possible to preclude any appreciable wear even in continuous operation. It is contemplated within the purview of this invention that the 6 shaft; means operatively connecting said sleeve with said blades and adapted to rotate said blades upon axial movement of said sleeve; a ?xed bracket; a link pivoted at one end on a horizon tal pivot pin in said bracket, and having a fork at its other end; a traverse ring disposed about said shaft; a ball-bearing having its outer race pivoted in said traverse ring for movement about an axis transverse to the axis of the shaft, and antifriction bushing 8 as well as the adjustment sleeve ID or either of said parts may be made of resin-impregnated fabric or any similar mate 10 its inner ring ?xed about said sleeve; a boss on said ring; a self-adjusting ball bearing in said rial. boss; a trunnion in the fork of the link, on which The adjustment of the propeller blades is ac said ball bearing is mounted, the link and ring complished, as described above, by turning the being so connected by the ball bearing that the threaded spindle 2| by means of the indicated Cardan drive member 48, which can be done 15 ring is capable of movement about two axes per pendicular to the axis of the link; a second ?xed manually, mechanically or electrically. In place bracket; a second self-adjusting ball bearing of an electric drive with rotating screw spindle mounted in said second ?xed bracket; a rotat a hydraulic drive can also be employed. able, threaded spindle journaled in said second The present invention has been described in detail with reference to speci?c embodiments. It 20 ball bearing; means ‘for rotating said spindle; a nut threaded on said spindle; and a third self is to be understood, however, that the inven tion is not limited by such speci?c reference but is broader in scope and capable of other embodi ments than those speci?cally described and il 25 lustrated in the drawings.‘ I claim: In an adjustable pitch propeller for aircraft, the combination of a propeller hub; propeller blades mounted in said hub to be adjustably ro adjusting ball-bearing mounted in said traverse ring diametrically opposite to the said boss and in which said nutis carried, the spindle and traverse ring being so related that when the spindle is rotated the traverse ring is moved about one of the axes perpendicular to the axis of the link, to slide said sleeve axially of the pro peller shaft, cause the link to pivot about the tated about their longitudinal axes; a propeller 3° ‘ ?rst ?xed bracket, and cause the spindle to pivot shaft on which said hub is rigidly mounted; a sleeve mounted coaxially and slidably on said about the second ?xed bracket. ROBERT PRAUSE.