BE1028416B1 - Device for overmolding a ring on a ferrule - Google Patents

Abstract

The present invention relates to a device (100) allowing rings (1, 2) to be overmolded in one go on two inner ferrules (10, 20) for aircraft turbine engine rectifiers. The device (100) comprises two molds (41, 42) arranged head to tail and a removable spacer element (50) creating a separation between the two rings (1, 2).

Description

Device for overmolding a ring on a ferrule Technical field

The present invention relates to a device and methods in the field of manufacturing parts for aircraft turbine engines.

Anterior

[9002] I! is known to overmold a ring on the inner shroud of a low pressure stator of an aircraft turbomachine. This requires placing the elements to form a mould, injecting a molding material, then heating in an oven, and demolding. All of these operations take time, and must be repeated for each shell. Summary of the invention

[9903] An object of the present invention is to reduce the time required to overmold a ring on the inner shroud of a low-pressure stator of an aeronet turbomachine.

[0004] To this end, the invention proposes a molding device for overmolding a first ring on a first inner shroud for aircraft turbomachinery rectifiers and a second ring on a second inner shroud for aircraft turbomachinery rectifiers, the device comprising: e a support configured to be in mechanical contact with a first radial surface, an outer surface, el a protruding part of the first shroud, and with a protruding part of the second shroud, s a first mold fixed to the support , so as to create a first hollow between the first mold and the support, the first hollow being capable of receiving the first shroud, s an intermediate element intended to rest on a second radial surface of the first shroud opposite to the first radial surface of the first ferrule, and intended to support a second radial surface of the second ferrule, "a second mold intended to rest on the first mold, so as to create a second hollow between the second mold and the support, the second hollow being capable of receiving part of the second ferrule, and e an injection system, the device being configured for injection, from the injection system, d a molding material between an interior surface of the first ferrule and the first mold, and between an interior surface of the second ferrule and the second mold.

[9905] With the invention, the injection and the heat treatment for the rings of two ferrules are done at the same time. I! there is therefore a significant time saving compared to the prior art where the rings were formed successively.

[9006] In one embodiment, the intermediate element is provided to leave a fluid passage between, on the one hand, a first space located between the inner surface of the first ferrule and the first mold, and, on the other hand , a second space located between the inner surface of the second ferrule and the second mold. The first (respectively second) space is provided for the first (respectively second) ring to be formed therein. The fluid passage allows injection of molding material from a single inlet for both rings.

[0007] In one embodiment, the injection system comprises only one injection orifice.

[9008] In one embodiment, the injection port is located in the first mold. 10609] In one embodiment, the spacer is made of a non-stick material, preferably non-stick as compared to silicone. Thus, it does not adhere to the molding material after it solidifies.

[9019] In one embodiment, the device is configured so that the second ferrule is arranged symmetrically with respect to the first ferrule. In other words, the ferrules are head to tail. This makes it possible to have a clearance favorable to dismantling.

In one embodiment, the device is provided to leave an outer surface and a first radial surface of the second shroud at least partially free during the injection of the molding material. This simplifies dismantling, and reduces the weight of the device.

[10011] In one embodiment, the device comprises a removable cover capable of resting on the second mold and the second ferrule. The cover closes the second space upwards. The function of the cover could be fulfilled by a projecting part of the second mold while remaining within the scope of the invention.

[0012] In one embodiment, the second mold is removable from the first mold. Thus, the device makes it possible to do only one! ring, the one on the first ferrule. To do this, it suffices to put neither the second mold nor the intermediate element.

[10013] In this embodiment, the device preferably comprises a removable cover able to rest on the second mold and the second ferrule and to rest on the first mold and the first ferrule. This makes it possible to use the same cover of a part when you want to overmold the two ferrules, in which case the second mold is placed, and the cover on the second mold, and, on the other hand, when you do not want to overmold only one virus, in which case the second mold is not placed, and the lid is placed on the first mold.

[9014] The invention further proposes a method for overmolding a first ring on a first inner shroud for aircraft turbomachinery rectifiers and a second ring on a second inner shroud for aircraft turbomachinery rectifiers, the method comprising the steps from:

(a) providing a device according to any preceding claim, (b) placing the first ferrule in the first recess such that the first radial surface, the outer surface, and the projecting portion of the first ferrule in mechanical contact with the support, (c) placing the intermediate element so that it rests on the second radial surface of the first ferrule, (d) placing the second ferrule on the intermediate element so that the part protruding from the second ferrule is in mechanical contact with the support, (e) placing the second mold so that it rests on the first mold and so that the second mold, the intermediate element, and the support form a second hollow in which is located at least a part of the second ferrule, and (A) injecting, from the injection system, a molding material between the inner surface of the first ferrule and the first mould, and between the inner surface of the second me ferrule and the second mould.

The method preferably comprises, between steps (e) and (f), placing a removable cover on the second mold and the second ferrule.

[9018] The invention further proposes a method for overmolding a first ring on a first inner shroud for aircraft turbine engine rectifiers, the method comprising the steps of: (a) providing a device according to the invention and in which the second mold is removable with respect to the first mold, and which comprises a removable cover able to rest on the second mold and the second ferrule and to rest on the first mold and the first ferrule,

(b) placing the first ferrule in the first recess so that the first radial surface), the outer surface, and the projecting part of the first ferrule are in mechanical contact with the support, (c) placing a removable cover on the first mold and the first ferrule, and (d) injecting, from the injection system, a molding material between the interior surface of the first ferrule and the first mold.

[9017] The process, whether for overmolding one or two ring(s), further comprises, preferably, after the injection, heating capable of solidifying the molding material.

The molding material is preferably silicone. Brief description of figures

Other characteristics and advantages of the invention will appear on reading the detailed description which follows for the understanding of which reference will be made to the appended figures, among which: - figure 1 is an axial and vertical section showing a part left of a molding device according to one embodiment of the invention, and - Figure 2 shows the path of a molding material during an injection. Embodiments of the Invention

The present invention is described with specific embodiments and references to figures, but the invention is not limited thereto. The drawings or figures described are only schematic and are not limiting.

[9021] In the context of this document, the terms "first" and "second" are used only to differentiate the different elements and do not imply any order between these elements. 10022] In the figures, identical or similar elements may bear the same references.

10023) Figure 1 illustrates a molding device 100 according to one embodiment of the invention. ballast intended for the injection of a molding material to form a first ring 1 on a first ferrule 10, and a second ring on a second ferrule 20. The first ferrule 10 is preferably identical to the second ferrule 20.

The ferrules 10, 20 have axial symmetry. Their axis of symmetry is located on the right with respect to FIG. 1. The device 100 is provided so that the ferrules 10, 20 are arranged symmetrically to one another with respect to a radial plane.

The first ferrule 10 (respectively second ferrule 20) has an inner surface 11 (respectively 21) facing the axis of symmetry of the first ferrule 10 (respectively second ferrule 20), an outer surface 12 (respectively 22} opposite to the inner surface 11 (respectively 21), a first radial surface 13 (respectively 23), and a second radial surface 14 (respectively 24) opposite the first radial surface 13 (respectively 23) It has a projecting part 15 (respectively respectively 25) such that the second radial surface 14 (respectively 24) extends more, radially outwards, than the first radial surface 13 (respectively 23).

The inner surface 11 (respectively 21) of the first ferrule 10 {respectively second ferrule 20) is concave, and the first ring 1 (respectively second ring 2) is attached thereto.

[9027] The device 100 comprises a support 30, a first part 31 of which forms a support for the first shroud 10 and a second part 32 of which forms a support for the projecting part 15. In the Hustré embodiment in FIG. 1, the first part 31 and the second part 32 of the support are two screwed parts.

The device 100 also comprises a first mold 41 fixed to the support 30, optionally in a removable manner. The first mold 41 is offset 30 radially inward relative to the second part 32 of the support

30, so as to create a first hollow 51 between them, in which the first ferrule 10 is placed. It is placed on the outside of the first hollow 51 leaving a first space located between the inner surface 11 of the first ferrule 10 and the first mold 41. The first space is preferably delimited axially, on one side, by the first part 31 of the support and, on the other side, partially, by an intermediate element 50. The first ring 1 is formed in the first space.

The spacer element 50 is removable relative to the other elements of the device 100. 11 is arranged on the second radial surface 14 of the first ferrule 10. The spacer element 50 is a ring of rectangular section. Its radial extension is equal to or greater than that of the second radial surface 14, 24. |! is provided so that its outer circumference is in contact with the second part 32 of the support 30 so as to be blocked radially outwards, which makes it possible to position it. |! is provided to leave a fluidic passage 61 between the first space, and a second space, described below, in which the second ring is formed

2.

[9030] The second ferrule 20 is placed above the intermediate element

50. Its projecting part 25 is placed in radial contact with the second part 32 of the support element 30.

The second mold 42 is located above the first mold 41. They are preferably fixed together in a removable manner. Nevertheless, they could be in one piece while remaining within the scope of the invention. In this case, the attachment between the first mold 41 and the support 30 is removable. If the second mold 42 and the first mold 41 are different parts, the device 100 preferably comprises an alignment means so as to position the second mold 42 with respect to the first mold.

41.

[9032] The second mold 42 is offset radially inwards with respect to the second part 32 of the support 30, so as to create a second hollow 52 between them, in which a part of the second ferrule 20 is placed. is placed on the outside of the second recess 20 leaving a second space located between the inner surface 21 of the second shroud 20 and the second mold 42. The second space is preferably delimited axially, on one side, partially, by the intermediate element 50 and, on the other side, by a cover 70. The second ring 2 is formed in the second space. The outer surface 22 and the first radial surface 23 of the second shroud 20 are preferably left partially free in the device 100 - they face the open outer space.

The cover 70 is preferably removable. I! is intended to be placed on the second ferrule 20 and the second mold 42 so as to axially close the second space on one side. it is also preferably provided to be able to be placed on the first ferrule 10 and the first mold 41 so as to axially close the first space on one side, in order to overmold only one ferrule in the device 100.

The device 100 also comprises a fluidic injection system 60 allowing a molding material to penetrate into the first space and the second space. The molding material is in liquid form. When injected by the injection system 60, it fills the first space and the second space. Next, the device 100 is heated, so as to solidify the molding material. The molding material, for example silicone, is intended to adhere to the ferrules, but not to the molds 41, 42, to the intermediate element 50 or to the cover 70.

The injection system 60 may include several injection ports. In one embodiment of the invention, the injection system 80 only comprises a single injection orifice 62, preferably located in the first mold 41. 11 is possible, while remaining within the scope of the invention. , that the injection system 62 comprises between 2 and 20 injection orifices 62, preferably arranged on the circumference of the device 100.

10036] The invention also proposes a process for overmolding the two rings 1, 2, each on one of the ferrules 10, 20, and a process for overmolding a single ring 1, on a ferrule 10. 10037] To overmold the two rings 1 , 2, each on one of the ferrules 10, 20, the method is preferably carried out as follows. We start from the support 30 fixed to the first mold 41. The first viral 10 is placed in the first hollow 51, blocked radially against the second part 32 of the support 30. The spacer element 50 is placed on the first ferrule 10, blocked radially against the second part 32 of the support 30. The second ferrule 20 is placed on the intermediate element 50, blocked radially against the second part 32 of the support 30. The second mold 42 is placed on the first mold 41, so as to leave a gap between them to form the second space. The cover 70 is placed on the second mold 42 and the second ferrule 20, so as to close the second space from above. It is tightened with screws so that the various elements are held in place during the injection. Is injected, by the injection system 60, the molding material in the first space, and in the second space, via the fluidic passage 61. The path 80 of the molding material is represented in FIG. so as to solidify the casting material. The cover 70 is removed. The second mold 42 is removed. The first 1 and the second 2 rings are joined vertically by the molding material which was present in the fluidic passage 61 during heating, and has solidified. This junction is cut, for example with a cutting blade. The second ferrule 20 and the second ring 2 are removed. Spacer 50 is removed. The first ferrule 10 and the first ring 1 are removed.

To overmold only the first ring 1 on the first ferrule 10, the method is preferably carried out as follows. We start from the support 30 fixed to the first mold 41. The first ferrule 10 is placed in the first hollow 51, blocked radially against the second part 32 of the support 30. The cover 70 is placed on the first mold 41 and the first ferrule 10, so as to close the first loud space. It is tightened with screws so that the various elements are held in place during the injection. Is injected, by the injection system 60, the molding material in the first space. It is heated, so as to solidify the molding material. The cover 70 is removed. The first ferrule 10 and the first ring 1 are removed.

[9039] In other words, the invention relates to a device 100 allowing rings 1, 2 to be overmolded in one go on two inner shrouds 10, 20 for aircraft turbomachinery rectifiers. The device 100 comprises two molds 41, 42 arranged head to tail and a removable spacer element 50 creating a separation between the two rings 1, 2.

The present invention has been described in relation to specific embodiments, which are purely illustrative and should not be construed as limiting. In general, the present invention is not limited to the examples illustrated and/or described above. The use of the verbs "understand", "include", "compose", 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 "un", "une", or of the definite article "le", "la" OR "FF", 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.

Claims (12)

Claims 1. Molding device (100) for overmolding a first ring (1) on a first inner shroud (10) for aircraft turbomachinery rectifiers and a second ring {2} on a second inner viral (20) for turbomachinery rectifiers aircraft, the device (100) comprising: e a support (30) configured to be in mechanical contact with a first radial surface (13), an outer surface (12), and a projecting part (15) of the first ferrule (10), and with a projecting part (25) of the second ferrule {20}, s a first mold (41) fixed to the support (30), so as to create a first hollow (51) between the first mold (41) and the support (30), the first recess (51) being capable of receiving the first shroud (10), s an intermediate element (50) intended to rest on a second radial surface (14) of the first shroud ( 10) opposite the first radial surface (13) of the first shroud (10), and intended to support a second radial surface (24) of the second me viral (20), e a second mold (42) intended to rest on the first mold (41), so as to create a second hollow (52) between the second mold (42) and the support (30), the second hollow (52) being capable of receiving part of the second ferrule (20), and "an injection system (60), comprising at least one injection orifice (62), the device (100) being configured for the injection, from the injection system (60), of a molding material between an inner surface (11) of the first ferrule (10) and the first mold (41), and between an inner surface (21) of the second ferrule (20) and the second mold (42). 2. Device according to claim 1, wherein the intermediate element (50) is provided to leave a fluid passage (61) between, on the one hand, a first space located between the inner surface (11) of the first shroud ( 10) and the first mold (41), and, on the other hand, a second space located between the inner surface (21) of the second ferrule (20) and the second mold (42). 3. Device according to any one of the preceding claims, in which the injection port (62) is located in the first mold (41). 4. Device according to any one of the preceding claims, in which the intermediate element (50) is made of a non-stick material. 5. Device according to any one of the preceding claims, comprising a cover (70) removable adapted to rest on the second mold (42) and the second ferrule (20). 6. Device according to any one of claims 1 to 4, wherein the second mold (42) is removable from the first mold (41). 7. Device according to the preceding claim, comprising a cover (70) removable able to rest on the second mold (42) and the second ferrule (20) and to rest on the first mold (41) and the first ferrule (10). 8. Method for overmolding a first ring (1) on a first inner shroud {10} for aircraft turbomachinery rectifiers and a second ring (2) on a second inner shroud (20) for aircraft turbomachinery rectifiers, the A method comprising the steps of: (a) providing a device (100) according to any preceding claim, (b) placing the first ferrule (10) in the first recess (51) so that the first radial surface (13), the outer surface (12), and the projecting part (15) of the first ferrule { 10} are in mechanical contact with the support (30), (c) placing the spacer (50) so that it rests on the second radial surface (14) of the first ferrule (10), (d) placing the second ferrule (20) on the intermediate element (50) so that the projecting part (25) of the second ferrule (20) is in mechanical contact with the support (30), (e) placing the second mold (42) so that it rests on the first mold (41) and so that the second mold (42), the spacer (50), and the support (30) form a second depression (52) in which is located at least a part of the second ferrule (20), and (A) injecting, from the injection system (60), a molding material between the inner surface (11) of the first ferrule (10) and the first mold {41}, and between the inner surface (21) of the second ferrule (20) and the second mold (42). 9. Method according to the preceding claim, further comprising, between steps (e) and (fj), placing a removable cover (70) on the second mold (42) and the second ferrule (20). 10. Method for overmolding a first ring {1} on a first inner shroud {10} for aeronautical turbine engine rectifiers, the method comprising the steps of: (a) providing a device (100) according to claim 7, (b) placing the first ferrule (10) in the first recess (51) so that the first radial surface (13), the outer surface (12), and the projecting part (15) of the first ferrule {10} are in mechanical contact with the support (30), (c) placing a removable cover (70) on the first mold (41) and the first ferrule {10}, and (d) injecting, from the injection system (60 ), a molding material between the inner surface (11) of the first ferrule (10) and the first mold (41). 11. Method according to any one of claims 8 to 10, further comprising, after injection, heating capable of solidifying the molding material. 12, A method according to any one of claims 8 to 11, wherein the molding material is silicone.