Patent ID: 12209512

The drawings in the FIGURES are not to scale. Generally, similar elements are denoted by similar references in the FIGURES. The presence of reference numbers in the drawings shall not be considered limiting, even when such numbers are indicated in the claims.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION

FIGS.1to4show an abstract geometric reference frame for quantifying and/or visualising properties of embodiments of the invention. For example, the reference X generally designates the “engine axle” of the aircraft turbomachine. The stages of the compressors and of the turbines of the aircraft turbomachine are generally stacked essentially along this engine axle. The reference frame inFIG.1shows the “axial” X, “circumferential” C and “radial” R directions, which correspond preferentially and respectively to directions parallel to the engine axle, essentially circular around the engine axle, and perpendicular to the engine axle. The terms “axially” and “radially” are derived from the terms “axial” and “radial” respectively with a similar preferred meaning. The terms “circumferential” and “radial” preferably refer to a polar coordinate system known to a person skilled in the art in each plane perpendicular to the engine axle.

FIG.1shows an example of embodiment of a group of vanes100according to the invention. The group of vanes100ofFIG.1comprises a first vane10comprising a first vane platform11delimited by an internal surface18defining a profile of a duct for a fluid flowing through a row of stator vanes of a stage of an axial turbomachine compressor. The first vane platform11allows the mechanical coupling with an external shell60and is also delimited by an external surface19. The first vane comprises a first vane blade12delimited by a first vane head14attached to said internal surface18of the first vane platform11and a first vane root15. The first vane root15is configured to come in interaction with an internal shell70of the row of stator vanes. The first vane platform11can be fitted after the first vane10has been machined.

The group of vanes100inFIG.1also shows a second vane20comprising a second vane platform21allowing for the mechanical coupling with an external shell60. The second vane platform21is delimited by an internal surface28for coming into contact with the external surface19of the first vane platform11and an external surface29. The second vane comprises a second vane blade22delimited by a second vane head24and a second vane root25. The second vane blade22is attached to the internal surface28of the second vane platform21. The first vane platform11comprises an opening30(not shown) to receive the second vane head24, so as to bring the first vane external surface19into contact with said second vane internal surface28. Thanks to the opening30(not shown), the blades of the first12and second22vanes are particularly close together.

The first vane10may be downstream or upstream of the second vane20.

FIG.2shows an example of embodiment of a group of vanes100according to the invention positioned between an external shell60and an internal shell70. The external shell60comprises a circumferential groove65to receive the platforms11,21of the group of vanes100. The external shell60comprises an attachment hole63for passing attachment means40secured to the first vane platform11. Here, the group of vanes100is attached to the external shell60of a turbomachine compressor stage by attachment means40which, for example, allow the group of vanes100to be bolted to the external shell60. The group of stator vanes100shown inFIG.2is an overlapped tandem of vanes. This can be attached to the external shell60by a single attachment means40. When the first10and second20vanes are attached to the external shell60, a flexible seal (not shown), for example of the silicone type, is applied between the head of the second vane24and the internal surface18of the first vane platform. Such a flexible seal allow to fill any space between the second vane blade22(or the second vane blade head24) and the lateral walls of the opening30.

Here, the group of vanes100is attached to the external shell60of a row of stator vanes of a turbomachine compressor using attachment means40. The attachment means40are inserted into an attachment hole63in the external shell60. For example, the attachment means40allow to bolt, rivet or weld the first vane10to the external shell60, thereby allowing to hold the external surface19of the first vane platform11and the external surface29of the second vane platform21against the external shell60. Thanks to the shoulder190(shown inFIG.3) of the first vane platform11, the external surface29of the second vane platform21is flush with the external surface19of the first vane platform. Such a flush arrangement allows to ensure a good contact between the external surfaces19,29of the first11and second21vane platforms respectively and the external shell60. Such a contact allows to ensure that the stator vane assembly100is rigid with the external shell60.

FIG.3shows an example of embodiment of the first vane10. As described inFIG.1, the first vane10comprises a first vane platform11comprising an opening30for receiving the head of a second vane24, the external surface19of the first vane then being in contact with said internal surface28of the second vane. The first vane platform11comprises a shoulder190defining a first segment17surrounding said opening30. The first vane platform21also defines a second segment16having a greater thickness than the first segment17. The external surface19of the first vane platform11refers to both the external surface of the first segment17and of the second segment16. Attachment means40are positioned on the external surface19of the second segment of the first vane platform. These attachment means40allow the first vane10to be attached to an external shell60of a compressor stage.

The opening30is an aperture between the internal surface28of the first vane platform and the external surface29of the first vane platform. The opening30or the aperture is entirely delimited axially and in a circumferential direction C by said second vane platform21. Axially means, when the group of vanes is attached in an axial compressor stator stage, the direction defined by the axis of the axial compressor. InFIG.3, the opening30is a hole between the internal surface18and the external surface19of the first vane platform. The aperture30, the opening or the hole is open only between the internal surface18and the external surface19of the first vane platform. Such a hole is made by milling, for example. The external surface19of the first vane platform11comprises a bath33around the opening30.

FIG.4shows an example of embodiment of the second vane20. As described inFIG.1, the second vane20comprises a platform21delimited by an internal surface28for coming into contact with the external surface19of the first vane platform11and an external surface29. The second vane20also comprises a second vane blade22delimited by a second vane head24and a second vane root25, the second vane blade22being attached to the internal surface28of the second vane platform21. The second vane root25(not shown) is configured to come in interaction with the internal shell70of a row of stator vanes.

The present invention has been described above in connection with specific embodiments, which are illustrative and should not be considered limiting. In general, the present invention is not limited to the examples illustrated and/or described above. The use of the verbs “comprise”, “include”, or any other variant, as well as their conjugations, can in no way exclude the presence of elements other than those mentioned. The use of the indefinite article “a”, “an”, or the definite article “the”, to introduce an element does not exclude the presence of a plurality of these elements. The reference numbers in the claims do not limit their scope.

In summary, the invention can also be described as follows.

A group of stator vanes100for a row of stator vanes of a stage of a turbomachine compressor, the vanes of the group of stator vanes100being close together and offering an easy assembly. The group of stator vanes100comprising a platform11of the first vane10comprising an opening30for receiving the head24of the second vane20, the external surface19of the first vane platform11being in contact with the internal surface28of the second vane platform21.