DEVICE FOR CONNECTING TWO SEGMENTS OF A PROPELLING NOZZLE
The invention relates to the field of propulsion nozzles, and in particular to a device ( 105 ) for connecting together first and second segments ( 103 a, 103 b ) of a propulsion nozzle that are made of thermally dissimilar materials. The device ( 105 ) comprises at least one pin ( 106 ) and an eccentric bushing ( 107 ). The pin ( 106 ) presents both a first axisymmetric surface ( 106 a ) that is to be housed in a radial orifice ( 108 ) of the first nozzle segment ( 103 a ) and also a second axisymmetric surface ( 106 b ) that is eccentric relative to said first axisymmetric surface ( 106 a ).
1 . A device for connecting together a first segment and a second segment of a propulsion nozzle made of materials that are thermally dissimilar, said device comprising at least:
a pin with a first axisymmetric surface that is to be housed in a radial orifice of the first nozzle segment and a second axisymmetric surface that is eccentric relative to said first axisymmetric surface; and
an eccentric bushing presenting an inside axisymmetric surface complementary to the second axisymmetric surface of the pin, and an outside axisymmetric surface, that is eccentric relative to said inside axisymmetric surface and that is to be housed in a radial orifice of the second nozzle segment.
2 . A device according to claim 1 having substantially the same radial offset between the axes of symmetry of the inside and outside axisymmetric surfaces of the eccentric bushing as between the axes of symmetry of the first and second axisymmetric surfaces of the pin.
3 . A device according to claim 1 , further including at least one axial retention member for axially retaining said pin.
4 . A device according to claim 3 , further including fastener members for fastening said axial retention member to one of said nozzle segments.
5 . A device according to claim 1 , wherein at least some of said axisymmetric surfaces are cylindrical.
6 . A propulsion nozzle comprising:
a first nozzle segment and a second nozzle segment made of thermally dissimilar materials, each having a radial shoulder bearing against a corresponding radial shoulder of the other one of said segments, together with a plurality of radial orifices facing corresponding orifices in the other one of said segments; and
a plurality of connection devices according to claim 1 , wherein the first axisymmetric surface of the pin of each of them is housed in one of said radial orifices of the first segment and the eccentric bushing is housed in the corresponding radial orifice of the second segment, the second axisymmetric surface of the pin co-operating with the inside axisymmetric surface of the eccentric bushing.
7 . A propulsion nozzle according to claim 6 , wherein each eccentric bushing is retained between an outer surface of the first nozzle segment and a shoulder in the radial orifice of the second nozzle segment in which the eccentric bushing is housed.
8 . A rocket engine including a propulsion nozzle according to claim 6 .
9 . A method of connecting together a first segment and a second segment of a propulsion nozzle that are made of thermally dissimilar materials, each of said segments including a plurality of radial orifices, the method comprising the following steps:
inserting eccentric bushings in the radial orifices of the second nozzle segment, each bushing presenting an inside axisymmetric surface and an outside axisymmetric surface that is eccentric relative to said inside axisymmetric surface;
causing a radial shoulder of the first segment to press against a radial shoulder of the second segment, the radial orifices of the first segment being put into register with corresponding orifices among the radial orifices of the second segment; and
inserting pins in the radial orifices, each pin presenting a first axisymmetric surface that is to be housed in a radial orifice of the first nozzle segment and a second axisymmetric surface of the same pin, that is eccentric relative to the first axisymmetric surface and complementary to the inside axisymmetric surface of one of said eccentric bushings, said first axisymmetric surface of the pin being aligned with the radial orifice of the first nozzle segment by turning the pin and the eccentric bushing in the corresponding radial orifice of the second segment.
10 . A method according to claim 9 , further including a step of installing at least one axial retention member for axially retaining said pins, so as to retain them in the radial orifices of the nozzle segments.
11 . A method according to claim 9 , wherein prestress is imparted between said segments by external tooling while the radial shoulder of the first segment is being caused to press against the radial shoulder of the second segment.