EP3495626A1 - Lever connection and corresponding turbomachine - Google Patents

Abstract

Disclosed is a lever connection (80, 270) for non-rotatably connecting a guide vane (10, 200) to a lever (52, 242) of a vane adjustment (54) of a turbomachine, wherein the vane (10, 200) extends along a vertical axis (H ) extending blade shank (12, 202). According to the invention, the lever (52, 242) is formed in one piece at a radially outer end (46, 236) of a substantially hollow-cylindrical clamping sleeve (50, 240) which surrounds the blade shank (12, 202) in sections coaxially and forms the shovel shaft (12, 202). and the clamping sleeve (50, 240) are coupled by way of a longitudinally positive-fit connection (98) or an end-face positive connection (278), and the blade shank (12, 202) is secured by means of a fastening element (84, 274), in particular a threaded nut (82, 272). , with the clamping sleeve (50, 240) along the vertical axis (H) braced. As a result, there is a separation of two different force flows acting on the guide vanes (10, 200), thereby reducing local load peaks. Furthermore, the invention relates to a turbomachine with such lever connections (80, 270) for producing a rotationally fixed coupling of guide vanes (10, 200) to a guide vane adjustment (54).

Description

The invention relates first of all to a lever connection for the non-rotatable connection of a guide vane to a lever of a vane adjustment of a turbomachine, wherein the vane has a vane shaft extending along a vertical axis.

In addition, the invention has a turbomachine with a plurality of lever connections for producing a rotationally fixed coupling of the guide vanes to a vane adjustment.

Compressors in axial flow machines, for example aircraft engines, usually include a vane adjustment in the area of the front compressor stages or in the high-pressure compressor. Due to the vane adjustment, the guide vanes of the relevant guide vane row are adjusted speed-dependent about their vertical axis, so that an absolute Leitradabströmwinkel is changeable. As a result, a stall during startup of the turbomachine or at low speeds can be prevented. A step load is reduced. Alternatively, a stall could be achieved by adjusting the blades of the compressor stages, but this is technically much more complex, so that the adjustment of the vanes has prevailed.

The adjustment of the guide vanes of a row of vanes is conventionally carried out mechanically by actuation of an actuator. The actuator usually acts via an adjusting ring and each by means of a lever on the vanes. The adjusting ring is arranged outside the turbomachine and usually positioned downstream and coaxial with the row of guide vanes as viewed in the flow direction. It is rotatable in the circumferential direction and displaceable in the axial direction of the turbomachine. In the case of several compressor stages to be adjusted, the adjusting rings are actuated at the same time via a control lever of the actuator which is mounted rotatably on the compressor housing and which extends in the axial direction of the turbomachine and is in each case connected to the adjusting rings.

In known vane adjustments, the lever is inserted in the radial direction of the turbomachine onto a vane shaft extending in the vertical direction of the vane. Thereafter, the lever on a small-area contact area of the blade shank positively fixed and secured by a screw. The screwing can be done by an internal thread or by an external thread. This type of lever connection requires a sufficiently thick blade shank for the design of the contact surfaces. Since the positive connection is realized only at the end and with relatively small contact surfaces, among other things locally higher mechanical stresses can arise.

The object of the invention is to provide a lever connection of a vane adjustment of a turbomachine for producing a rotationally fixed connection between a vane and a lever, which avoids the disadvantages mentioned above. In addition, it is an object of the invention to provide a turbomachine with lever connections according to the invention.

The object is initially achieved by a lever connection with the features of claim 1.

In a lever connection for non-rotatably connecting a guide vane with a lever of a vane adjustment of a turbomachine, wherein the guide vane has a blade axis extending along a vertical axis, the lever is integrally formed on a radially outer end of the vane shank partially coaxially enclosing, substantially hollow cylindrical clamping sleeve and the blade shank and the clamping sleeve are coupled via a longitudinally form-fitting connection or an end-face positive connection, and the blade shank can be braced with the clamping sleeve along the vertical axis by means of a fastening element, in particular a threaded nut.

As a result, a separation of the power flows is given, since the blade shank is subjected essentially only to train and the clamping sleeve by means of integrally molded thereon lever at least substantially only by bending moments during adjustment of the guide vane. In comparison to a conventional lever connection, the risk of locally increased mechanical stresses is reduced and overall a more uniform load distribution is achieved. The longitudinal-side positive connection also extends parallel to the vertical axis of the blade shank. The threaded nut is usually self-locking. Instead of a threaded nut, for example, a threaded bolt can be used as a tensioning or fastening element.

Preferably, the clamping sleeve has a collar for securing the radial position of the guide vane in a housing of the turbomachine, wherein there is a defined gap between the collar and the housing. As a result, a smooth storage is given.

According to a technically advantageous development, between a radially inner end of the clamping sleeve and the collar of the clamping sleeve is formed a cylindrical bearing portion for pivotally mounting the guide vane in the housing. As a result, a particularly large contact surface between the clamping sleeve and the housing of the turbomachine is given, resulting in a robust and durable storage results.

Preferably, at least one bushing is arranged between a bore of the housing and the bearing portion of the clamping sleeve. As a result, in the case of a suitable material selection of the clamping sleeve, the at least one at least approximately hollow cylindrical bush and the housing of the turbomachine in this area a low-wear storage possible. In addition, tolerance compensation can be realized by means of the at least one bushing.

Preferably, a threaded portion for the threaded nut is formed at a radially outer end of the blade shank. As a result, a mechanically reliable and, if necessary, releasable connection between the blade shank and the clamping sleeve is given.

Preferably, the radially outer plate of the vane forms a contact surface for the radially inner end of the clamping sleeve. As a result, a unilateral abutment for the clamping sleeve is given to the blade shank.

In the case of a first embodiment variant of the lever connection, the blade shank has a longitudinal external toothing with a first recess below the threaded section and the clamping sleeve has a longitudinal internal toothing with a second cutout in the region of the lever to create the longitudinal positive connection, wherein the two recesses are designed such that an in the recesses fit snugly securing plate during clamping of the blade shank with the clamping sleeve between the blade shank and the lever to the play-free connection can be clamped. As a result, a permanently play-free, rotationally fixed connection between the clamping sleeve with the lever and the blade shank is given. A transmission of Verstellmomente by means of the longitudinal side Positive connection, while the transmission of bending moments on the clamping sleeve is done with the lever, causing a division of these different power flows. The locking plate also serves to secure the position of the preferably self-locking threaded nut.

In the case of a second embodiment of the lever connection, the front-side positive connection is formed with a first directed towards the outer radial end of the blade shank spur on the radially outer plate and with a direction in the direction of the first spur toothing second spur toothing at the radially inner end of the clamping sleeve. Due to the oppositely oriented and mutually engaging in an at least partially positive engagement serrations a permanently backlash-free connection between the clamping sleeve with the lever and the blade shank is given. In addition, the two serrations ensure proper centering of the clamping sleeve with respect to the blade shank. The blade shank remains in the result completely free of bending or torsional moments and is therefore charged exclusively to train, resulting in a strict power flow separation results, whereby the occurrence of local mechanical stresses within the vane is largely avoided.

Preferably, the two serrations each have an irregular tooth pitch. As a result, a clear angular position between the blade shank and the clamping sleeve to facilitate the assembly of the lever connection is given.

In the case of a technically advantageous embodiment, a recess for a securing plate for securing the position of the threaded nut is provided in the region of the clamping sleeve and / or the lever. As a result, in addition to the preferably self-locking threaded nut further securing the nut against unintentional release is given.

Preferably, the blade shank has an at least approximately cylindrical centering collar, which abuts at least in sections on an inner centering section in the region of the radially outer end of the clamping sleeve. As a result, a reliable guidance of the blade shank is given in the clamping sleeve.

A turbomachine according to the invention is equipped with a plurality of lever connections according to one of the claims 1 to 11 for producing a rotationally fixed coupling of vanes to a guide vane adjustment. As a result, a decoupling of the force flows is given, whereby the risk of the formation of local mechanical voltage peaks is avoided.

Figur 1:

eine perspektivische Ansicht einer Leitschaufel für eine erste Ausführungsvariante einer Hebelanbindung,

Figur 2:

eine perspektivische Ansicht einer Spannhülse mit einem einstückig seitlich daran ausgebildeten Hebel für die erste Ausführungsvariante der Hebelanbindung,

Figur 3:

eine Draufsicht auf die erste Ausführungsvariante der Hebelanbindung in einem montierten Zustand,

Figur 4:

einen Längsschnitt der montierten Hebelanbindung von Fig. 3 entlang der Schnittlinie IV-IV,

Figur 5:

einen Querschnitt der Hebelanbindung von Fig. 4 entlang der Schnittlinie V-V,

Figur 6:

einen Querschnitt der Hebelanbindung von Fig. 4 entlang der Schnittlinie VI-VI,

Figur 7:

eine perspektivische Ansicht einer Leitschaufel für eine zweite Ausführungsvariante einer Hebelanbindung,

Figur 8:

eine perspektivische Ansicht einer Spannhülse mit einem einstückig seitlich daran ausgeformten Hebel für die zweite Ausführungsvariante der Hebelanbindung,

Figur 9:

eine schematische Seitenansicht auf die zweite Ausführungsvariante der Hebelanbindung in einem montierten Zustand,

Figur 10:

eine Draufsicht auf die montierte zweite Ausführungsform der Hebelanbindung von Fig. 9,

Figur 11:

einen Längsschnitt durch die montierte Hebelanbindung von Fig. 10 entlang der Schnittlinie XI-XI.

They show schematically:

FIG. 1:

a perspective view of a guide vane for a first embodiment of a lever connection,

FIG. 2:

a perspective view of a clamping sleeve with an integrally formed laterally thereto lever for the first embodiment of the lever connection,

FIG. 3:

a top view of the first embodiment of the lever connection in an assembled state,

FIG. 4:

a longitudinal section of the mounted lever connection of Fig. 3 along the section line IV-IV,

FIG. 5:

a cross section of the lever connection of Fig. 4 along the section line VV,

FIG. 6:

a cross section of the lever connection of Fig. 4 along the section line VI-VI,

FIG. 7:

a perspective view of a guide vane for a second embodiment of a lever connection,

FIG. 8:

a perspective view of a clamping sleeve with an integrally molded laterally thereon lever for the second embodiment of the lever connection,

FIG. 9:

a schematic side view of the second embodiment of the lever connection in an assembled state,

FIG. 10:

a plan view of the mounted second embodiment of the lever connection of Fig. 9 .

FIG. 11:

a longitudinal section through the mounted lever connection of Fig. 10 along the section line XI-XI.

In the context of the present description, terms such as "radial", "radially outward", "radially outer", "radially inward" and "radially inner" - unless explicitly pointed to another orientation - refer to a machine longitudinal axis X of the turbomachine according to the invention , which represents the axis of rotation of a rotor of the turbomachine.

Information such as "lateral" and "transverse" refer to a vertical axis H of a guide vane of the turbomachine, which extends substantially radially to the machine longitudinal axis X.

FIG. 1 shows a perspective view of a guide vane for a first embodiment of a lever connection. A guide vane 10 shown in the installed position has, inter alia, a vane shank 12 extending along a vertical axis H with an airfoil 14. The vane 10 is pivotally receivable in a housing, not shown here, a turbomachine also not shown about the vertical axis H. Perpendicular to the vertical axis H, the machine longitudinal axis X of the turbomachine runs. At a radially inner end 16 of the blade shank 12, a larger diameter, radially outer plate 18 is formed. At a radially outer end 20 of the blade shank 12, a threaded portion 22 is provided. A radially inner airfoil root 24 of the airfoil 14 merges into a smaller diameter, radially inner plate 26, while a radially outer airfoil root 28 merges into the larger diameter plate 18.

On the blade shank 12, at least in sections, a longitudinal external toothing 30 extending parallel to the vertical axis H is formed. The longitudinal external toothing 30 can be designed as a uniform involute, trapezoidal, triangular toothing or the like. In the blade shank 12 is an approximately parallelepiped and parallel to the vertical axis H extending recess 34 is introduced, which, starting from the annular groove 32 via a small Length L extends in the direction of the radially inner end 16 of the blade shank 12. The recess 34 takes at least one tooth 36 of the longitudinal external teeth 30 completely and here by way of example a directly circumferentially to this adjacent further tooth 38 partially, wherein of the tooth 38 only a narrow side wall 40 stops. The recess 34 serves to receive a locking plate, not shown here (see. Insb. Fig. 3 . 4 . 6 ). The plate 18 also has an approximately annular contact surface 42 for a clamping sleeve of the lever connection (see. Fig. 2 ).

FIG. 2 shows a perspective view of a clamping sleeve with an integrally formed laterally thereon lever for the first embodiment of the lever connection. In the region of a radially outer end 46 of a substantially hollow cylindrical basic body 48 of a clamping sleeve 50 is a lever 52 of a drawing merely indicated guide vane adjustment 54 of the turbomachine integrally formed. The clamping sleeve 50 has an approximately disk-shaped collar 56 for securing the radial position of the guide vane in a housing of the turbomachine, not shown here. The clamping sleeve 50 has a longitudinal internal toothing 58 which corresponds to the longitudinal external toothing of the blade shank (see in particular. Fig. 1 ) is executed and extending from the radially outer end 46 to a radially inner end 60 of the clamping sleeve 50 parallel to the vertical axis H. The vertical axis H in turn is orthogonal to the machine longitudinal axis X. At the radially outer end 46 of the clamping sleeve 50 is provided in the region of the base 48 of the clamping sleeve and the lever 52 has a recess 62 for the locking plate. The recess 62 has a first and a second side wall 64, 66 and a bottom 68, wherein the side walls 64, 66 are oriented perpendicular to the bottom 68.

FIG. 3 illustrates a plan view of the first embodiment of the lever connection in an assembled state. In a mounted state of a lever connection 80 according to the invention, the threaded portion 22 is connected to the blade shank 12 of the vane 10 with the clamping sleeve 50 by means of a preferably self-locking threaded nut 82 as a fastener 84 and pivotally received in a housing 86 of the turbomachine by means of the lever 52. The collar 56 of the clamping sleeve 50 secures the guide blade on one side in the radial direction. A locking plate 88 has two at least substantially triangular tabs 90, 92, which are brought to secure the threaded nut 82 by appropriate bending to the plant to this. The fuse element 88 is at least partially in the recess 62 of the lever 52 of the clamping sleeve 50. When mounting the lever connection 80 by tightening or tightening the nut 82, the locking plate 88 at least partially between this and the clamping sleeve 50 and the recess 62 in the lever 52 and the hidden here recess in the blade shank 12 clamped.

FIG. 4 shows a longitudinal section of the mounted lever connection of Fig. 3 along the section line IV-IV. The vane 10 has the vane shank 12 and the blade 14 and the radially outer and the radially inner plates 18, 26. The vane 10 is located in relation to the machine longitudinal axis X in the installed position. The blade shank 12 of the vane 10 is inserted to form the lever connection 80 in the clamping sleeve 50 and clamped by means screwed onto the threaded portion 22 threaded nut 82, wherein between the collar 56 of the clamping sleeve 50 and the housing 86, a narrow gap 96 remains. Between The longitudinal external toothing 30 of the blade shank 12 and the longitudinal internal toothing 58 of the clamping sleeve 50 thus has a longitudinal positive connection 98.

Between the radially inner end 60 of the clamping sleeve 50 and the collar 56, a cylindrical bearing portion 100 for pivotally supporting the guide vane 10 in a stepped bore 102 of the housing 86 is formed. Between the bearing portion 100 and the stepped bore 102 three at least approximately hollow cylindrical bushes 104, 106, 108 are arranged here by way of example, wherein on the bushing 108 a vertically away from the vertical axis collar 110 is integrally formed between the plate 18 and a shoulder 112th the stepped bore 102 is located. The plate 18 further includes the abutment surface 42 as an abutment of along the vertical axis H against each other braced vane 10 and the clamping sleeve 50.

By means of the tab 90 and the second tab of the securing plate 88, which is not visible here, an additional security against rotation of the additionally preferred self-locking threaded nut 82 takes place. The securing plate 88 also has a bore section 118 for passing through the threaded section 22 of the blade shank 12, perpendicular thereto that is parallel to the vertical axis H extending back portion 120 and a parallel to the machine axis X oriented clamping portion 122, which lies in the recess 34 of the longitudinal external teeth 30 of the blade shank 12 and in the recess 62 of the lever 52 of the clamping sleeve 50. The two recesses 34, 62 are in this case according to the invention designed such that at least the clamping portion 122 of the locking plate 88 wedged during clamping of the blade shank 12 with the clamping sleeve 50 between the blade shank 12 and the lever 52 to their play-free connection. A cross-sectional geometry of the bore portion 118, the back portion 120 and the clamping portion 122 of the locking plate 88 are approximately U-shaped.

The inventive design of the lever connection 80, a separation of forces acting on the vane 10 power flows to protect against local load peaks is ensured as Verstellmomente transmitted via the longitudinally positive connection 98 and bending or torsional moments by the lever 52 and the clamping sleeve 50 on the guide vane 10 ,

FIG. 5 shows a cross section of the lever connection of Fig. 4 along the section line VV. The lever connection 80 is formed inter alia with the longitudinal external teeth 30 of the blade shank 12, which is in engagement with the longitudinal internal teeth 58 of the clamping sleeve 50 and in this case the longitudinal-side positive connection 98 represents. The clamping sleeve 50 with the blade shank 12, which is accommodated therein coaxially and in sections in a form-fitting manner, is pivotably received about the vertical axis H in the housing 86 in order to allow different angles of attack of the blade of the blade shank 12, which is not shown here. The centering of the blade shank 12 in the clamping sleeve 50 is in this case preferably on an outer diameter 124 of the longitudinal positive connection 98. The sleeve 104, among other things, a smooth and low-friction pivoting of the clamping sleeve 50 is ensured in the housing 86.

FIG. 6 illustrates a cross section of the lever connection of Fig. 4 along the section line VI-VI. The blade shank 12 is non-rotatably connected by means of the longitudinally form-locking connection 98 of the lever connection 80 with the clamping sleeve 50 and the lever 52 integrally formed thereon and accommodated pivotably about the vertical axis H in the housing 86. The clamping portion 122 of the locking plate 88 is located in the recess 62 of the lever 52 and in the recess 34 of the longitudinal outer teeth 30 of the blade shank 12. The clamping portion 122 by tightening the threaded nut not shown here during assembly of the lever connection 80 between the side wall 40 of the remaining (Residual) tooth 38 and the opposite side wall 66 of the recess of the lever 62 wedged like a wedge. As a result, any circumferential clearance of the longitudinally-shaped interlocking connection 98 in relation to the vertical axis H is permanently and reliably eliminated. The clamping portion 122 is in this case connected by means of the parallel to the vertical axis H extending back portion 120 with the bow-shaped or clip-like locking plate 88. By the locking plate 88 is exemplarily both the redundancy of the position assurance of the threaded nut and the backlash of the lever connection 80 causes.

FIG. 7 shows a perspective view of a guide vane for a second embodiment of a lever connection. A guide vane 200, which in turn is shown in its installed position, comprises an at least substantially cylindrical vane shank 202 and an airfoil 204. To illustrate the spatial position of the components within the turbomachine, the vertical axis H and the machine longitudinal axis X are again shown. The blade shank 202 has a radially inner end 206, in the region of which a larger diameter radially outer plate 208 is formed analogously to the first embodiment variant. At a radially outer end 210 of the blade shaft 202, a threaded portion 212 is provided. A radially inner airfoil root 214 of the Blade blade 204 merges into a smaller diameter radially inner plate 216, while a radially outer blade root 218 connects to plate 208. As a difference to Fig. 1 instead of a longitudinal external toothing of the blade shaft 202 on the plate 208, a first spur toothing 220 with an irregular tooth pitch pointing in the direction of the threaded section 212 or the radially outer end 210 of the blade shaft 202 is provided. The spur gear 220 may have teeth with a deviating from the usual Evolentenform, virtually any geometry. Along the vertical axis H in the direction of the plate 208, an annular groove 222 and a cylindrical centering collar 224 adjoin the threaded portion 212 of the blade shaft 202. The centering collar 224 has a diameter D _{2 which is} at least slightly larger than a diameter D _{1 of} the blade shank 202. Peripheral to the spur gear 220 is further provided in the direction of the radially outer end 210 of the blade shank 202 facing bearing surface 234 for the clamping sleeve of the lever connection to the vane adjustment (see. FIG. 2 Reference numeral 54).

FIG. 8 illustrates a perspective view of a clamping sleeve with an integrally molded laterally thereon lever for the second embodiment of the lever connection. At a radially outer end 236 of an at least approximately hollow cylindrical base body 238 of a second embodiment of a clamping sleeve 240 drawn in the installation position, a lever 242 is again preferably integrally formed for coupling the guide vane adjustment (not shown). FIG. 2 Reference numeral 54). According to the embodiment of FIG. 2 is on the main body 238 of the clamping sleeve 240 in turn a circumferential collar 246 and a flange integrally formed, which extends perpendicular to the vertical axis H radially outward. Notwithstanding the longitudinal internal toothing of the first embodiment of the clamping sleeve (see. FIG. 2 ), the base body 238 of the clamping sleeve 240 on a cylindrical and concentric to the vertical axis H extending through hole 248. The vertical axis H is again oriented at right angles to the machine longitudinal axis X. At a radially inner end 250 of the clamping sleeve 240 is provided as a further constructive difference, a second front toothing 252 with an irregular pitch, which corresponds to the spur toothing of the blade shank of FIG. 7 is designed. In a hollow-like transition zone 254 between the radially outer end 236 of the clamping sleeve 240 and the lever 242, a bore 256 or a recess for at least partially receiving a locking plate, not shown here is introduced.

FIG. 9 shows a schematic side view of the second embodiment of the lever connection in an assembled state. The blade shank 202 merely indicated with the blade airfoil 204 is inserted into the clamping sleeve 240 to create the second embodiment of a lever connection 270. The blade shank 202 and the clamping sleeve 240 with the lever 242 and the flange-like collar 246 are braced against one another mechanically by means of a threaded nut 272 screwed onto the threaded section 212 and preferably self-locking as a fastening element 274 along the vertical axis H. Between the threaded nut 272 and the radially outer end 236 of the clamping sleeve 240, a locking plate 276 for redundant rotation of the threaded nut 272 is also arranged against uncontrolled release. The clamping sleeve 240 encloses the blade shank 202 of the guide blade 200 in the assembled state in sections coaxially. The spur toothing 220 of the plate 208 is in the assembled state of the lever connection 270 shown here in positive engagement with the correspondingly shaped spur gearing 252 of the clamping sleeve 240 to create an inventive frontal positive connection 278, which also acts centering. The radially inner airfoil root 214 merges into the smaller diameter plate 216.

The second embodiment of the lever connection 270 also enables an effective separation of the force flows or moments acting on the guide vane 200, since only minimal tension and the clamping sleeve 240 are subjected to bending or torsional moments in order to minimize local mechanical stresses of the vane shank 202.

FIG. 10 shows a plan view of the mounted second embodiment of the lever connection of Fig. 9 , The clamping sleeve 240 of the fully assembled lever connection 270 is fixed in position by means of the collar 246 at least on one side radially in the housing 86 of the turbomachine and pivotally received by the lever 242 about the vertical axis H. The blade shank 202 is clamped for this purpose by means of the screwed onto the threaded portion 212 threaded nut 272 in the direction of the vertical axis H with the clamping sleeve 240. To secure the position of the threaded nut 272, the locking plate 276 is inserted between this and the clamping sleeve 240, which has a first and a second tab 280, 282. Further, the locking plate 276 has a parallel to the vertical axis H extending engagement portion 284, which is at least partially received in the bore 256 of the lever 242.

FIG. 11 illustrates a longitudinal section through the mounted lever connection of Fig. 10 along the section line XI-XI. The vane shank 202 of the vane 200 is connected to the Clamping sleeve 240 is clamped by means of screwed onto the threaded portion 212 threaded nut 272 for producing the lever connection 270 along the vertical axis H, wherein a defined gap 290 between the housing 86 and the collar 246 of the clamping sleeve 240 remains. As a result, a smooth pivotability of the guide vane 200 about the vertical axis H is ensured by actuating the integrally formed to the clamping sleeve 240 lever 242 by means of the guide vane adjustment of the turbomachine, not shown here (see. Figure. 2 Reference numeral 54). The non-rotatable and at the same time permanently play-free connection between the blade shank 202 of the guide vane 200 and the clamping sleeve 240 is ensured by the along the vertical axis H strained front-side positive connection 278, which with the spur gear 220 of the plate 208 and the engaged with this front teeth 252 on the radial inner end 250 of the clamping sleeve 240 is formed. The blade 204 is formed between the plate 208 and the smaller diameter plate 216 integral therewith.

Between the radially inner end 250 of the clamping sleeve 240 and the collar 246, a cylindrical bearing portion 292 for pivotally mounting the guide vane 200 in a stepped bore 294 of the housing 86 is formed. Between the bearing section 292 and the stepped bore 294, only four hollow cylindrical bushes 296, 298, 300, 302 are arranged here by way of example, wherein between the sleeve 302 located furthest in the direction of the plate 208 and the annular contact surface 234 of the plate 208 as well a shoulder 304 is a hollow cylindrical intermediate layer 306. The contact surface 234 serves as an abutment of the along the vertical axis H against each other braced vane 200 and clamping sleeve 240 to create the lever connection 270. The centering collar 224 of the blade shank 202 also lies against an inner centering portion 308 of the clamping sleeve 240 for further optimization of the guide.

The hook-like locking plate 276 comprises two triangular tabs, of which only the tab 282 is visible here, to which a bore section 310 adjoins, to which the engagement section 284 adjoins at right angles. The redundant position securing the threaded nut 272 by means of the locking plate 276, passes through the central bore portion 310 of the threaded portion 212 of the blade shaft 202 and which is clamped between the tightened nut 272 and the radially outer end 236 of the clamping sleeve 240. The two triangular tabs of the locking plate 276 can to ensure the purpose of the backup by bending to rest against the Threaded nut 272 or be brought to at least two of the hexagonal surfaces. The bore portion 310 of the locking plate 276 is added to the completion of the securing position of the threaded nut 272 in the bore 256 of the lever 242 of the clamping sleeve 240.

The invention relates to two variants of a lever connection for pivoting guide vanes in a compressor part of a turbomachine in which a separation of the acting force and moment flows is realized by a clamping sleeve, such that the blade shank essentially only with tensile forces and the clamping sleeve primarily with bending or Torsionsmomenten is applied. As a result, local mechanical load peaks are significantly reduced. In addition, the lever connection is permanently backlash-free and redundantly secured against uncontrolled loosening. Also disclosed is a turbomachine having a multiplicity of lever connections according to the invention for adjusting guide vanes in a compressor part by means of the guide vane adjustment.

reference numeral

10

Guide vane (1st Var.)

12

blade shank

14

airfoil

16

radially inner end (shovel shaft)

18

radially outer plate

20

radially outer end (shovel shaft)

22

threaded portion

24

radially inner airfoil root

26

radially inner plate

28

radially outer blade root

30

Longitudinal external toothing (shovel shaft)

32

ring groove

34

Recess (longitudinal external toothing)

36

tooth

38

tooth

40

Sidewall (tooth)

42

Contact surface (plate)

46

radially outer end (adapter sleeve)

48

Basic body (clamping sleeve)

50

Adapter sleeve (1st Var.)

52

lever

54

Guide Vane

56

Federation

58

Longitudinal internal toothing (clamping sleeve)

60

radially inner end (clamping sleeve)

62

Recess (adapter sleeve, lever)

64

first sidewall

66

second side wall

68

ground

80

Lever connection (1st Var.)

82

threaded nut

84

fastener

86

Housing (turbomachine)

88

Locking plate

90

flap

92

flap

96

gap

98

Longitudinally positive connection

100

cylindrical bearing section (clamping sleeve)

102

stepped bore (housing)

104

Rifle

106

Rifle

108

Rifle

110

collar

112

Shoulder (stepped bore)

118

Bore section (locking plate)

120

Back section (locking plate)

122

Clamping section (locking plate)

124

Outer diameter (long-side positive connection)

200

Guide vane (2nd Var.)

202

blade shank

204

airfoil

206

radially inner end (shovel shaft)

208

radially outer plate

210

radially outer end (shovel shaft)

212

threaded portion

214

radially inner airfoil root

216

radially inner plate

218

radially outer blade root

220

first spur toothing (plate)

222

ring groove

224

Centering collar (shovel shaft)

232

Sidewall (tooth)

234

contact surface

236

radially outer end (adapter sleeve)

238

Basic body (clamping sleeve)

240

Adapter sleeve (2nd Var.)

242

lever

246

Federation

248

Through Hole

250

radially inner end (clamping sleeve)

252

second spur toothing (adapter sleeve)

254

Transition zone

256

Hole (lever)

270

Lever connection (2nd Var.)

272

threaded nut

274

fastener

276

Locking plate

278

front-side positive connection

280

flap

282

flap

284

engaging portion

290

gap

292

cylindrical bearing section (clamping sleeve)

294

stepped bore (housing)

296

Rifle

298

Rifle

300

Rifle

302

Rifle

304

shoulder

306

between Leger

308

Inner centering section (clamping sleeve)

310

Bore section (locking plate)

312

D _1,2

diameter

H

vertical axis

L

Length of recess (spline)

X

Machine longitudinal axis (turbomachine)

Claims (12)

A lever connection (80, 270) for non-rotatably connecting a vane (10, 200) to a lever (52, 242) of a vane adjustment (54) of a turbomachine, wherein the vane (10, 200) has a vane shank extending along a vertical axis (H) (12, 202), characterized in that the lever (52, 242) in one piece at a radially outer end (46, 236) of the blade shank (12, 202) in sections coaxially enclosing, substantially hollow cylindrical clamping sleeve (50, 240) is formed and the blade shank (12, 202) and the clamping sleeve (50, 240) via a longitudinally positive connection (98) or a front-side positive connection (278) are coupled and the blade shank (12, 202) by means of a fastening element (84, 274) , in particular a threaded nut (82, 272), with the clamping sleeve (50, 240) along the vertical axis (H) is clamped. Lever connection (80, 270) according to claim 1, characterized in that the clamping sleeve (50, 240) has a collar (56, 246) for radial securing position of the guide vane (10, 200) in a housing (86) of the turbomachine, wherein between the collar (56, 246) and the housing (86) has a defined gap (96, 290). Lever connection (80, 270) according to claim 1 or 2, characterized in that between a radially inner end (60, 250) of the clamping sleeve (50, 240) and the collar (56, 246) of the clamping sleeve (50, 240) is a cylindrical Bearing portion (100, 292) for pivotally supporting the guide vane (10, 200) in the housing (86) is formed. Lever connection (80, 270) according to claim 3, characterized in that between a bore (102, 294) of the housing (86) and the bearing portion (100, 292) of the clamping sleeve (50, 240) at least one bush (104, 106, 108, 296, 298, 300, 302). Lever connection (80, 270) according to one of the claims 1 to 4, characterized in that at a radially outer end (20, 210) of the blade shank (12, 202) has a threaded portion (22, 212) for the threaded nut (82, 272) is trained. Lever connection (80, 270) according to one of the claims 1 to 5, characterized in that the radially outer plate (18, 208) of the guide vane (10, 200) has a bearing surface (42, 234) for the radially inner end (60, 250 ) of the clamping sleeve (50, 240) is formed. Lever connection (80) according to one of the claims 1 to 6, characterized in that the blade shank (12) has a longitudinal external toothing (30) with a recess (34) below the threaded portion (22) and the clamping sleeve (50) has a longitudinal internal toothing (58) a recess (62) in the region of the lever (52) for providing the longitudinally positive locking connection (98), wherein the two recesses (34, 64) are formed such that a in the recesses (34, 64) accurately recordable locking plate (88 ) When clamping the blade shank (12) with the clamping sleeve (50) between the blade shank (12) and the lever (52) can be clamped to the play-free connection. Lever connection (270) according to one of the claims 1 to 6, characterized in that the front-side positive connection (278) with a first in the direction of the outer radial end (210) of the blade shank (202) directed spur gear (220) on the radially outer plate (208 ) and with a in the direction of the first spur gear (220) directed second spur gear teeth (252) at the radially inner end (250) of the clamping sleeve (240) is formed. Lever connection (270) according to claim 8, characterized in that the two serrations (220, 252) each have an irregular tooth pitch. Lever connection (270) according to claim 8 or 9, characterized in that in the region of the clamping sleeve (240) and / or the lever (242) has a bore (256) for a locking plate (276) for securing the position of the threaded nut (272) is provided. Lever connection (270) according to one of the claims 8 to 10, characterized in that the blade shank (202) has an at least approximately cylindrical centering collar (224) which at least partially at an inner centering section (308) in the region of the radially outer end (236) Clamping sleeve (240) is applied. Turbomachine with a plurality of lever connections (80, 270) according to one of the claims 1 to 11 for producing a rotationally fixed coupling of the guide vanes (10, 200) to a guide vane adjustment (54).

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