DE1906764A1 - Rigid hub for propellers and turbo machines with variable pitch - Google Patents

Description

rHing.H.Weickm. κ. ": \ 0r.K.Finck8 '^^^' φ ^ ^> ''

«- .. U. '. GFAlilfeici.i, ...,: S-, nBHuhar χδ ^ Α ^ τνΓη c η c /

8 Munich 27, fwü.iir. 22 \ ^ V '- ^ 1 ΰ UD / b H

3905-68

SOCIETE DS CONSTRUCTIOiI ET D'EXPLOITATIOlT DE MATERISLS ET KOTEURS

S C E rl Ji

"Rigid" liabe for propellers and turbomachines with variable Pitch.

The invention relates to having

Adjusting screws, support rotors, flight motors, fans and axial turbo machines, which have no joints, "Rigid" have called v / earth and a rotating axle, a hub body attached to this Achoe and on this Hub bodies have attached arms, at the free ends of which the wings of a screw are attached, each arm at least three bundles of stacked lamellas, which around the slope change axis of the attached to the Wings are spread around. Concerned by such having; the invention in particular, if not exclusively, such fuj * rotary wing aircraft (helicopters, autogircs or the like).

The invention aims in particular

to train such men in such a way that they know how to absorb the great forces that are exerted on them by the flights they carry _β

BATH

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A property according to the invention is thereby

characterized in that the lamellar bundle is an onä of the same arm are connected to each other and to the hub body by holding means, \ tfelche are designed so that the arm a relatively high resistance to bending and one, relatively has little torsional resistance.

The invention is explained below with reference to the drawing by way of example.

Pig. 1 shows a top view of an arm belonging to a so-called "rigid" liatoe according to the invention.

Pig. Figure 2 shows a side view of the same arm with parts broken away.

Pig. 3 is a Scheisatic cut along the line III-III of the Pig. 2.

Pig. Figure 4 shows a detail of the arm

in section along the line IV-IV of Pig · 1 with parts being broken away.

Pig. 5 is a separate perspective view of the hub according to the invention covering the arms of the arms corresponding to the preceding figures, the bracing of the arms being omitted to simplify the drawing.

The invention is hereinafter in its

Application to a so-called "rigid" hub for a three-winged one Rotor explained.

First of all, there are certain properties

the rotie- used for rotary wing aircraft and axial turbo engine ^, fairy. The supporting structures and one property of it is a stack of sheets remembers manufactured parts

Except for a total turning movement with the

The axis of possessions can make each wing of a rotor perform three kinds of movements. The first of these Bewenia2issn ₉ ^S3 Bü tradif "& - ■ movement" called, moves; the wing in FLSR Breliefoene & ® & Tragwerko from an approximately radial middle St-allnng after iFöra © or backward "The av / eite""Flatterbewegung- ³ gesaunt © Β @ ΐί © <* supply shifts the wings in a zn the ürMisbsae of the structure is vertical, containing the wing, 31% third,; _ ■ -

^{■;: l} - 103814/003? - ^SAD

• Movement called "Slope Change Movement" is a rotation of the wing about an axis referred to below as the "pitch change axis", which shows the change in the angle of attack of the Wing is intended. This change in slope is made up of a common slope change, which is done in the same way concerns all of the wings of the rotating structure, and possibly a cyclical change in pitch which to each wing according to the y.on him in relation to the appa-

einqenOTTiinenen Stel.Iuη ^

advice to which it is attached j / sniffed together. These two changes are controlled by known mechanical means.

It is well known that metal parts that work with alternating stresses have very different ones Fatigue limit as it depends on local manufacturing defects. In general, poor performance produces or any other fault with such a stress, a crack, which propagates quickly in the part, .if this consists of a single piece.

If the part is made up of a certain number of thin piled-up parts that are glued together or not

• th elements (thin sheets) consists, the progression is made the cracks from one element to another are avoided. This avoids the breakage or at least occurs considerably later than with a part consisting of only a single element of the same shape. This property is used in the hub body of the rotor and the arms. For the hub body of the rotor, stacks of each other are useful glued sheets are used, while the arms are not joined by gluing.

The rotor as a whole is a rotating axle 1 (FIG. 5), one on this axle 1 by suitable means Means not shown attached hub body 2, the main object of the invention forming Arne 3 and at the free ends the Arne 3 attached wing 4 (three in the illustrated embodiment).

Each arm 3 (Fig. 1 and 2) is through

at least three bundles 5, 6, 7 and 8 (four in the example described), each of which is formed by stacked lamellae ¹

1098 U / 0037 BADORfGlNAU

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Len formed v / ird, which have the same shape in plan view (their thicknesses can vary from one lamella to another, but are constant for each lamella) and at the Edges of a pyramid or a prism are arranged, the bundles 5, 6, 7 and 8 according to the invention with one another and with the head body 2 are connected by holding means, which are designed so that the arms 3 have a high resistance to bending and have a relatively low torsional resistance.

These holding means point at each arm

rigid clamps, which are formed by groups of struts, which at mutual distances approximately to the slope change axis I-I (Fig. 1) approximately perpendicular Levels are arranged and the bundles 5, 6, -7, 8 hold.

These holding means also have metal sheets 9

and 10, which are within the volume of the arm at least part of their length the opposite Hold bundle 5, 7 and 6, 8 and go through pitch change axis I-I.

The sheet 9, which is from below

explained reasons "Rücktriftsteg" is called, adapts itself two times the profile of the arm shown in Fig. 1, with it between two successive middle lamellae of the Lamella bundle 5 and 7 occurs. The sheet 9 is expediently on the side of the hub body 2 with a first cutout ^ and provided with a second cutout H on the side of the wing 4.

The sheet metal 10 called "Flattersteg" fits

expediently to the profile of the arm 3 visible in FIG. 2, it being between two successive middle lamellae the lamella bundle 6 and 8 occurs. The sheet 10 is also on the side of the liabenkörpers 2 with a cutout 15 and on the side of the wing 4 with a cutout 16 »

It is noticeable that the sheets are

9 and 10 in the example described at right angles within of the arm cut on the axis I-I, and although these Ausfii can be realized in different ways

1098 1 4 / Π037

BATH ORIGINAL

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e.g. consist of two parts (Pig. 3), "which are on both sides of the Sheet 9 arranged and connected to this by rivets 17 or on other, other Y / eise.

The struts 1t (of which a group of four combined into a clamp is shown in Pig * 3 is) are expedient by U-shaped profile pieces formed, which are provided at their ends with shoulders 18 with which they are on two successive lamella bundles, e.g. 5 and 6. The bottom of the U, the bundles 5 to 8 and the sheets 9 and 10 are, although they are in Pig. 3 are cut, not hatched, to make the drawing clearer close. After its installation, each strut is supported on the one hand with the paragraphs 18 of its ends on half of the lamellas the corresponding lamella bundle and on the other hand with provided at the base of their profile flats 19 on the Sheet metal 9 and 10. The struts 11 are, as in Pig.1 and 2, arranged so that their flats 19 •. in pairs on both sides of the sheets 9 and 10 opposite one another '.. lie. The struts 11 are arranged in evenly distributed .α groups of four along the arm 3. The four struts " Gen 11 of each group are attached to each other by rivets 20 (Pig. 3) or any other V / eise, creating the flats 19 adjacent struts are pressed against the • sheet metal 9 or 10 separating them. Press the struts 11 after their mutual union into groups of four, the bundles of lamellas introduced into the adjacent paragraphs 18 and the Sheets 9 and 10 together. The through the * struts 11 and the Sheets 9 and 10 formed arrangement holds the Lanellenbündel and gives the arms 3 suitable flexural and torsional resistances, as explained below in the description of the operation of the whole hub.

Appropriately v / earth rings 12 are provided,

which are arranged on each bundle between the strut groups 11 and the lamellae of the bundle are suaancenspanning.

These rings 12 are grounded through the corners

two Profilütücke formed with a U-shaped cross-section, whose each half of the lamellae of a bundle of lanelles and on the corresponding sheet 9 or 10 with a shoulder and

1098U / 0037 BADORJGlNAt

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a flattening (which are not shown in the figures) as described in FIG. 3 for the ends of the struts 11 became. When attaching the two profile pieces of a ring 12 arranged on a bundle by rivets 21 or the like. to press these hold the lamellas of the bundle in question together they compared to the corresponding sheet 9 or 10. These rings 12 are evenly spaced on the four bundles 5, 6,

7 and 8 arranged between the strut groups 11.

The hub body 2 ″ of the example described It is expediently formed by a stack of metal sheets, which can be glued together, and has approximated the shape of a star 3 with three legs 22, between which three cutouts 23 are provided.

Each on a leg 22 of the hub body 2 by fastening means described below attached arm 3 is attached in relation to the hub body 2 in the special case shown so that the furthest spacing bundles 5 and 7 are at least approximately in the plane of the hub body, while the on fewest diverging bundles 6 and 8 in a perpendicular and at least approximately through the axis 1 of the rotor going level.

These fastening means are expediently through with the adjacent ends of the bundle 5, 6, 7 and

8 connected fork heads 24, 25, 26 and 27 are formed.

The clevises 24 and 26 are with the

Hub body 2 on the sides of each leg 22 symmetrical with respect to the pitch change axis I-I (Pig. 1), which coincides with the axis of symmetry of the leg 22, bolted. They keep the ends of the lanelle bundles 5 and 7 with them Using bolts 30 and 31. ■

On one side and the other of the

relevant leg 22 on the free 2nde of the same, holders 28 and 29 are arranged so that the fork heads 25 and 27 _f \, v / which they carry, or to which they belong, lie on both sides of the \ - plane of the hub body 2 "

This froic end of the thigh 22 is kicking into the interior of the arm 3 at the through the cutouts 13 and

■ "1098U / 0037 BAD OWGlNAl

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and 15 of the sheets 9 and 10 and has a section 32, the outline of which in relation to the axis I-I is synchronous ·. ·

Each holder 28 or 29 is supported

the leg 22 of the hub body 2 with a rounded projection 33 (Fig. 4) »which between the axis 1 and the ground of the cutout 32 occurs, and through lugs 34 on both sides of the same away. The holders 28 and 29 are attached to the leg 22 by bolts 35 and 36, which through each holder, the Leg 22 and two approaches 34 step. The latter press the stack of thin metal sheets of the leg 22 on both sides of the cutout 32 zv / ischen together. Furthermore, a bolt 37 pushes through the holders 28, 29 and the leg 22 zv / ischen the front of cracks 33 and the bottom of the cutout 32 occurs, the projections; '33 against the sheet metal stack of the leg The hole 38 for the passage of the bolt 37 through the leg 22 has a larger diameter than the shaft 39 of the Bolt 37 so that it does not come into contact with the metal sheets of the leg 22 when the free end of the leg is under the action of the holders 28 and 29 deflects, as described below.

The fork heads 25 and 27 hold the ends A bundle 6 and 8 by bolts 40 and 41 in a plane, which contains the axis I-I and is perpendicular to the plane of the credit body 2.

Each arm 3 is on its side by its side

of the wing opposite end provided with a mounting portion 42 having four fork heads 43, 44, 45 and 46 eist v / are to which by means of bolts 54 fastens the ends of the bundles 5, 6 _S 7 and 8 · The attachment portion 42 supports still in Mechanical devices shown in FIGS. 1 and 2 for holding the wing 4. Mechanical devices, e.g. Legs. Toroidal screw can be provided to bring the wing into the parking pitch z \ x by pivoting about the axis 47.

Each arm 3 has a control arm 49 5) provided, v / elcher on the fastening part 42

1098U / 0037

BATHROOM QRlGiNAI-

strengthens and is flexurally and torsionally stiff .. In the case of the one shown Example, it is arranged approximately in the plane of the hub body s 2 and with its free end 50 with a Control device for setting the slope 51, 52, 53 of a known type connected.

Of course, the arms can

3, the control arms 49 and the device for controlling the incline are in fairings, not shown, which give them good aerodynamic properties.

The above so-called "rigid" ITabe works as follows.

Each arm connected to a wing '4

3 is subject to various forces, regardless of the centrifugal force resulting from the total rotation of the wings, which are caused by come from the three movements that the wing can perform.

If a wing 4 makes a "return movement

"executes, the lamella bundle 5 and 7 are alternately exposed to tensile and compressive forces. If it is assumed that the lamella bundle 5 experiences a tensile stress and the lamella bundle 7 experiences a compressive stress, the arm 3 sets a high resistance to such a stress due to the ^; the Bundle 5 exerted tension and the stiffness of the sheet for a shear stress, whereby the bundles 5 and 7 are practically held in their mutual position. The bundle 5 is stretched and straight and therefore, by means of the various groups of four struts 11, holds the entirety of the four bundles 5, 6, 7 and 8 and in particular the bundle 7, which has a tendency to buckle under pressure. The rings 12 serve to prevent local buckling of the lamellas of the bundle 7 between the strut groups 11 when this is subject to compressive stress., Without these clamps could be the lamellae of the bundle 7 ausei nander spreading. The processes are similar for the other possible case in which the bundle 5 is subject to compressive stress and the bundle 7 is subjected to tensile stress.

It should be noted that for "Rücktrif t> -

• 109814/0037 _B äd original

• ·

~ ^v ~ Ί 9Ό6764

movements "of each wing 4 of the hub body 2 and its legs 22 a great rigidity in the sealing of this loading · own movement, and that thus the arrangement formed by the hub body and the connecting arms the "back drift movements" opposes a high resistance.

When the wing'4 makes a "flapping motion"

'Executes, the lamellar bundles 6 and 8 are in turn exposed to alternating tensile and compressive forces, and the sheet metal 10 serving as a web for the bundles 6 and 8 experiences shear stresses. For the same reasons as above, the arm 3 offers high resistance to such stress. The tensile and compressive forces acting on the bundles 6 and 8, however, are transmitted to the fork heads 25 and 27, which in turn are firmly connected to the holders 28 and 29. These forces generate a moment which acts on the two holders 28 and 29 in relation to their projections 33. This moment bends the leg 22 in its entirety and, via the holders 28 and 29, the section of the leg 22 clamped between them. This latter bending is facilitated by the presence of the cutout 32 and by the fact that the moment acts on the leg 22 via the lugs 34 which lie at the end of the leg. The arrangement formed by the hub body 2 with its leg 22 and the connecting arm 3 thus has a relative resilience for the "fluttering movements" of the wing 4 despite the high resistance of the arm 3 for such a movement. It should be noted that the centrifugal force generated by the movement of the wing is absorbed as shear stress by the shafts of the bolts 35 and 36, since the shaft 39 of the bolt 37 does not come into contact with the leg 22 even with the above deflections. In addition, the resilience of the arrangement formed by the leg 22 and the Ans 3 for the "fluttering movements" can be adjusted by loading the length of the holders 28 and 29.

Finally, the SorsionsViiclersta & ci

of a §® & e & invention arm 3 ' relatively small * bite gives the "change in pitch" of each wing. as & ureii sweet eteuern _s that to the on © Since the Flugeis Lie

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A corresponding torsional moment is exerted at the end of each arm 3. This is done using the system for "Incline control", which exerts forces directed parallel to the axis 1 of the rotor on the ends 50 of the control arms 49.

The flat and back drift movements of the

Plügel 4 v / ground through a balance between the forces acting on this Plügel and the mechanical reactions of the According to the invention arms 3 are determined, and the pitch change of the ploughshare is done by the pitch change device. controls.

The so-called "rigid ⁴¹ have invented

poor according to the invention has numerous advantages, among others the following:

- great maneuverability;

- With a rotary wing aircraft, very good damping of the rolling and pitching movements of the apparatus;

- simple execution ;

- Reduction of maintenance costsj ~ ease

ORIGINAL INSPECTED

Claims (1)

Claims 1.) "Rigid" hub without joints for S ^ ellscrews with a rotating axle, a hub body attached to this axle and arms attached to the hub body, at the free ends of which the wings of a screw are attached, each arm having at least three bundles of stacked lamellas, v / which around the pitch change axis the fixed to the arm wing are distributed around, characterized in _t that the lamellar bundles (5, 6, 7, 8) of one and the same arm (3) are connected to the hub body (2) to each other by retaining means, v / hich is formed are that the arm has a high resistance to bending and a relatively low resistance to torsion. 2.) Hub according to claim 1, characterized in that the holding means comprise rigid "clamps (11), which are arranged at mutual distances in planes approximately perpendicular to the axis of slope change (I-1), wherein each clamp holds the bundle (5 »6, 7» 8) on its circumference. 3.) Hub according to claim 1, characterized in that the holding means have metal sheets (9, 10), v / which connect the bundles to one another over at least part of their length and through the axis of slope change (I-I) walk. 4o) hub according to claim 2, characterized in that each clamp (11) is formed by struts will, which preferably consist of U-profiles, which are united at their ends and have shoulders (18) at these ends into which the lamellar bundles enter and in which they are clamped. 5.) hub according to claim 3 and 4, characterized characterized in that the struts are flattened at their ends (19) which are supported on the metal sheets (9, 10) and which are not attached to these metal sheets. 6.) Hub according to claim 5, characterized in that the flats (19) of two adjacent Strut ends are attached to the corresponding sheet (9 or 10) on both sides of the same support, and that a fastening member. the one caused by the two flattened areas and the one between them 109814/0037 - 12 - 3 ^ 05-68 *% J borrowed sheet metal holds formed stack. 1906764 7.) hub according to claim 6, characterized in that that the fastening member is a rivet (20) which passes through the two flats and the sheet metal. 8.) Hub according to claim 2, characterized in that rings (12) between the clamps (11) longitudinally of each lamella bundle are arranged and the lamellae of the bundle, tighten. 9.) Hub according to claim 8, characterized in that each ring (12) is formed by two U-profiles - which are united with each other at two ends and at the other ends have heels in which * a lamella bundle enters, and in which it is clamped. 10.) hub according to claim 3 and 9 »thereby characterized in that the ends with which the two profile pieces a ring clamping a lamella bundle are united, have flattened areas, which are located on the with these Bundle connected sheet support on both sides of the same, the arrangement by one through the two flats and the sheet metal stepping rivet (21) is held. 11.) hub according to claim 1, characterized in that the massive or useful by a The hub body (2) formed by stacks of metal sheets glued together approximately has the shape of a star, in which the number of legs (22) is equal to that of the wings (4). 12.) Hub according to claim 11, in which at least certain bundles of each arm are not arranged in the plane of the hub body, characterized in that these bundles (6, 8) are connected to the corresponding leg (22) of the star by means of fork heads (25, 27) attached to this Legs are fastened by holders (28, 2ο.) Which carry them or form part of them. 13.) Hub according to claim 12, characterized in that each holder (28, 29) is supported on a leg (22) by at least two support parts, one of which is a projection (34) with a flat starting surface and the other is a rounded one Projection (33) is, the approach (34) near the end of the leg (22) and the pre ν 1098U / 0037 - - ^! OHfGiNALINSPHCTED J Leap. (33) near the firmly connected to the hub body (2) bound rotatable axis (1) is arranged at a distance from the extension (34), which the bending resistance of the the leg (22) and the arm (3) formed arrangement in a rotatable axis (T) and the pitch change axis (I-I) containing level determined. 14.) Hub according to claim 13, characterized in that each holder '(28, 29) on a leg (22) by at least one through the holder, the shoulder (34) and the leg (22) passing bolts (35) and is fastened by at least one bolt (37) passing through the holder in the vicinity of the projection (33) and the leg (22), v / obhe latter bolt (37) presses the projection (33) strongly against the hub body (2) . 15.) hub according to claim 11, in which certain bundles of each arm in the plane of the hub body are arranged, characterized in that these bundles (5, 7) with a leg (22) over directly on the sides of the leg (22) attached fork heads (24, 26) are connected. 16.) Hub according to claim 14, characterized in that the metal sheets (9, 10) on the side of the hub body (2) have cutouts (13 »15), such that the The end of the leg (22) can at least partially enter the interior of the arm (3). 17.) Hub according to claim 1 to 16, characterized in that each arm (3) on its of the hub body (2) the distal end is provided with a fastening part for fastening a paddle (42), v / elcher fork head (43 »44, 45, 46) ″ to which the bundles (5» 6, 7, 8) are attached. 18.) hub according to claim 1 to 17 «characterized in that each arm (3) has four lamellae bundles (5, 6, 7 »8), which along the edges of a pyramid with a rhombus-shaped base, the tip of which is from the hub body (2) is removed, and the height of which coincides approximately with the slope change axis (I-I), v / above the bundles (5, 6, 7 »8) roughly in the opposite edges of the pyramid : .-: ■ -. 10981 4 / Π037 BADOftlGINAL • • a · · yes:: 3905-68 mide unifying planes are arranged, the bundles (5, 7) farthest from the axis (I-I) being approximated in the plane of the hub body (2) and the other two Bundle (6, 8) in the through the rotating axis (1) and the Slope change axis (I-I) lie in the plane. 19 ·) Hub according to claim 18, characterized in that that the edges of the metal sheets (9, 10) are pushed into the bundle of stacked lamellas, preferably between two adjacent lamellas of the middle section of the stacks forming the bundles. 20.) Hub according to claim 18, characterized in that that the sheet (9) connecting the bundles (5f 7) is arranged in the plane which passes through these bundles (5, 7) corresponding edges of the pyramid, while the sheet metal ('10) connecting the other bundles (6, 8) consists of two parts consists, which on both sides of the sheet (9) in the by these bundles (6, 8) corresponding edges of the pyramid going level are arranged, with the two'Teile des The sheet metal (10) is rigidly attached to the sheet metal (9) in the vicinity of the axis (I-I), preferably by rivets (17). 21.) hub according to claim 18, characterized in that the holder (28, 29) ι which the bundle (6, 8) and are arranged opposite one another on both sides of the leg (22), each having swei lugs (34), which arranged symmetrically with respect to the plane passing through the slope axis (I-I) and the rotating axis (1) are, and that the leg (22) has a cutout (52), whose outline is symmetrical with respect to this plane and extends between the lugs (34) up to the vicinity of the projection (33) extends. 22.) hub according to claim 1 to 21, characterized in that each arm (3) with a control arm ■■; (49) provided for adjusting the pitch, which at the ^f fastening part (42) of the Plügels is secured and extending from '} this fixing part (42) towards the hub body (2), wherein it extends from the pitch change axis ( II) removed. 109814/003? BAD ORIGINAL.; ■■ * "■