阅读说明：本技术 连接元件以及用于制造这种连接元件的环的方法 (Connecting element and method for producing a ring of such a connecting element ) 是由 J-B.考德特 A.蒙德林 A.图莫 于 2020-03-04 设计创作，主要内容包括：本发明涉及一种连接元件(1；20),包括第一环(3；22)和第二环(2；21),两个环绕中心轴线(X1；X20)相对于彼此旋转,第一环(3；22)包括具有用于所述相对旋转的与第二环(2；21)相互作用的接触表面(9；28)的接触部分(3-1；22-1)和旨在刚性地固定到支撑件上的紧固部分(3-2；32)。所述接触部分(3-1；22-1)由第一材料制成,所述紧固部分(3-2；32)由与第一材料不同的第二材料制成,第一材料的硬度严格大于第二材料,第二材料的结构疲劳强度严格大于第一材料。(The invention relates to a connecting element (1; 20) comprising a first ring (3; 22) and a second ring (2; 21), the two rings rotating relative to each other about a central axis (X1; X20), the first ring (3; 22) comprising a contact portion (3-1; 22-1) having a contact surface (9; 28) for said relative rotation interacting with the second ring (2; 21) and a fastening portion (3-2; 32) intended to be rigidly fixed to a support. The contact portion (3-1; 22-1) is made of a first material, the fastening portion (3-2; 32) is made of a second material different from the first material, the first material having a hardness strictly greater than the second material, and the second material having a structural fatigue strength strictly greater than the first material.)

1. A connecting element (1; 20) comprising a first ring (3; 22) and a second ring (2; 21), the first ring (3; 22) and the second ring (2; 21) rotating relative to each other about a central axis (X1; X20), the first ring (3; 22) comprising a contact portion (3-1; 22-1) having a contact surface (9; 28) for said relative rotation interacting with the second ring (2; 21) and a fastening portion (3-2; 32) intended to be rigidly fixed to a support,

characterized in that said contact portion (3-1; 22-1) is made of a first material, said fastening portion (3-2; 32) is made of a second material different from the first material, the hardness of the first material being strictly greater than that of the second material, and the structural fatigue strength of the second material being strictly greater than that of the first material.

2. A connecting element according to claim 1, comprising a hinged connection (1), wherein the contact surface (9) of the contact portion (3-1) of the first ring (3) is in direct sliding contact with the contact surface (6) of the second ring (2).

3. The connecting element of claim 2, wherein the first material is one of the following: bronze, steel, cobalt alloys, titanium alloys, nickel alloys.

4. A connecting element according to claim 2 or 3, wherein the second material is one of the following: titanium alloy, aluminum alloy, nickel alloy.

5. A connecting element according to any of claims 2-4, wherein the fastening portion (3-2) of the first ring (3) comprises a radially extending annular flange (11).

6. A connecting element according to claim 1, comprising a bearing (20) with roller elements (23), wherein at least one row of roller elements (23) is interposed between a contact surface (28) of a contact portion (22-1) of a first ring (22) and a contact surface (25) of a second ring (21).

7. The connecting element of claim 6, wherein the first material is one of the following: 100C6, high speed steel M50, ASP2060 or M62.

8. The connecting element of claim 6 or 7, wherein the second material is one of the following materials: low carbon steel, medium carbon steel, titanium alloy, aluminum alloy, M50NiL, 32CVD13, INCONEL 718.

9. A connecting element, wherein the fastening portion of the first ring (22) is a squirrel cage (32) comprising a radial fastening edge (33) and a substantially axial portion (35) having a plurality of windows (36) distributed circumferentially.

10. Method for manufacturing a first ring (3; 22) of a connecting element (1; 20) according to any one of the preceding claims, comprising the steps of:

(a) the contact portion (3-1; 22-1) is machined from a rod or from a first material by additive manufacturing and has a contact surface (9; 28);

(b) the contact portion (3-1; 22-1) is mounted in the fixed support so that a portion (10; 29) of its outer surface is free;

(c) the second material is stored in the form of a powder with which the fastening part (3-2; 32) is manufactured on said free part (10; 29) of the contact part (3-1; 22-1); and

(d) the fastening portions (3-2; 32) are finally dimensioned by machining.

11. A method of manufacture according to claim 10, wherein step (c) of the method is performed by 3D printing.

12. Manufacturing method according to claim 10, wherein a mould having the shape of the fastening part (3-2; 32) is mounted on the contact part (3-1; 22-1) such that only the surface (10; 29) on which the fastening part (3-2; 32) is to be formed is free inside the mould, the fastening part (3-2; 32) being formed in step (c) by injecting powder into the closed mould under vacuum, the shape thus obtained being consolidated by Hot Isostatic Pressing (HIP).

Technical Field

The present invention relates to a connection assembly having a ring made of various materials, such as a bearing assembly having a squirrel cage, for example for a gas turbine, or a hinged connection such as a ball joint. Finally, the invention also relates to a method for producing such a ring made of a plurality of materials.

Background

In the aeronautical industry, it is known to use an articulated connection in the form of a metal ball-and-socket joint to fix two members, such as a connecting rod and a structural component, which translate with respect to each other, while allowing relative rotational movement of these members.

Such ball and socket joints typically include an inner ring and an outer ring both made of metal. The inner surface of the inner ring is designed to be mounted on the shaft, while the outer surface is substantially spherical and designed to interact with a corresponding inner surface of the outer ring. Thus, the inner and outer rings have three mutual rotational degrees of freedom and are fixed to each other in translation.

The outer ring may have a radially outwardly extending fastening flange intended to be rigidly fixed to the fixed support, for example by means of through screws. Such an outer ring is made in one piece. However, the required properties and performance of the outer ring are twofold: due to the bearing contact, the inner surface, which moves in relative contact with the inner ring, has a high hardness and a high fatigue strength, while having a certain degree of flexibility and a high resistance to the fastening flange.

Bearing assemblies having squirrel cages, such as for gas turbines, suffer from similar problems.

The bearing assembly includes an inner ring having an inner raceway, an outer ring having an outer raceway, and a plurality of roller elements received between the inner and outer raceways. The outer ring also has a squirrel cage extending axially from said outer ring, the outer ring and the squirrel cage being made in one piece. The cage has an edge for fastening to a fixed support, for example by means of through screws. The cage also comprises an axially intermediate portion having a plurality of windows distributed circumferentially, so that the cage has a certain degree of flexibility to withstand various types of vibrations of the assembly. It is also known to provide a lubricant film between the outer ring and the surface of the fixed support, said film being housed in a sealed chamber between the two seals to filter the vibrations.

Currently, the compromise is reached by using a metal having satisfactory properties for the technical and structural requirements of such a ring of connecting components. For example, the rings may be made of M50NiL and the raceways may also be hardened.

Disclosure of Invention

The present invention aims to overcome the above-mentioned disadvantages.

More particularly, the invention aims to provide a connecting element with a ring whose raceway has improved specific properties, which connecting element also has a fastening portion with improved specific properties, without compromise on either side, said connecting element being cheaper, easy to manufacture and lighter

The invention relates to a connecting element comprising a first ring and a second ring, the two rings rotating relative to each other around a central axis. The first ring comprises a contact portion having a contact surface for said relative rotation interacting with the second ring and a fastening portion intended to be rigidly fixed to the support.

According to the invention, the contact portion is made of a first material and the fastening portion is made of a second material different from the first material. The first material has a hardness strictly greater than the second material. The second material has a structural fatigue strength that is strictly greater than the first material.

According to another advantageous but not mandatory feature of the invention, such connection elements are hinged connections and may also comprise the following features, used alone or in any technically feasible combination:

the contact surface of the contact portion of the first ring is in direct sliding contact with the contact surface of the second ring.

The contact surface is spherical.

The connecting element is a ball joint.

-the first material is one of the following materials: bronze, steel, cobalt alloys, titanium alloys, nickel alloys.

-the second material is one of the following materials: titanium alloy, aluminum alloy, nickel alloy.

The fastening portion of the first ring comprises an annular flange.

The flange extends radially.

The fastening portion of the first ring comprises a plurality of through holes, each for receiving a fastening screw, so as to be rigidly fixed to the support.

According to another advantageous but not mandatory feature of the invention, such a connecting element is a bearing with roller elements, and may also comprise the following features, used alone or in any technically feasible combination:

at least one row of roller elements is interposed between the contact surface of the contact portion of the first ring and the contact surface of the second ring.

-the first material is one of the following materials: 100C6, high speed steel M50, ASP2060 or M62.

-the second material is one of the following materials: low carbon steel, medium carbon steel, titanium alloys, aluminum alloys, M50NiL, 32CVD13, and INCONEL 718.

The first ring is an outer ring and the second ring is an inner ring.

The fastening part of the first ring is a squirrel cage.

The squirrel cage comprises a fastening edge and a portion with a plurality of windows distributed circumferentially.

The rim extends radially.

The portion with the plurality of windows distributed circumferentially extends substantially axially.

The fastening portion of the first ring comprises a plurality of through holes, each for receiving a fastening screw, so as to be rigidly fixed to the support.

The invention also relates to a method for manufacturing a first ring of a connecting element according to any of the above embodiments. The manufacturing method comprises the following steps:

(a) the contact portion is machined from a bar or from a first material by additive manufacturing and has a contact surface;

(b) the contact portion is mounted in the fixed support so that a portion of its outer surface is free.

(c) The second material is stored in powder form, with which the fastening part is manufactured in said free part of the contact part.

(d) The dimensions of the fastening portion are finally determined by machining.

According to another advantageous but not mandatory feature of the invention, step (c) of the method is carried out by 3D printing.

According to this particular embodiment of the method, in step (b), the contact portion is mounted in a fixed support such that only the surface on which the fastening portion is to be made is flush with the mounting surface of said support. For this purpose, the contact portion may be accommodated in a recess of the support. According to a particularly advantageous embodiment, said outer surface portion may be ground so as to be perfectly flush with said mounting surface of the support.

Thus assembled, the contact portion and the support are assembled in the 3D printer. In step (c) of the method, a continuous layer of a second material is deposited on the free surface of the contact portion until the fastening portion is formed.

According to another advantageous but not mandatory feature of the invention, a mould having the shape of the fastening portion is mounted on the contact portion, so that only the surface on which the fastening portion is to be formed is free inside the mould.

In step (c) of the method, the fastening portion is formed by injecting powder into a closed mold under vacuum. The shape thus obtained is consolidated by Hot Isostatic Pressing (HIP).

Alternatively, the powder of the second material may be melted by electron beam melting, selective laser melting or by direct metal deposition.

According to other embodiments, the method for manufacturing a ring may further comprise the step of depositing a surface coating.

Drawings

The invention will become clearer from reading the following description, given purely by way of non-limiting example.

The following description refers to the accompanying drawings in which:

FIG. 1 is a cross-sectional schematic view of a ball-and-socket joint mounted on a shaft according to one embodiment of the present invention; and

fig. 2 is a schematic partial cross-sectional view of a bearing element with a squirrel cage according to an embodiment of the invention.

Detailed Description

Fig. 1 shows a ball joint connecting element with a central axis X1, which is generally designated by reference numeral 1.

The ball joint 1 comprises an inner ring 2 and an outer ring 3.

The inner ring 2 comprises a substantially cylindrical inner surface 4 intended to be positioned against the outer periphery of a respective cylindrical shaft 5. The inner ring 2 also comprises an outer surface 6 having a spherical profile, more particularly as a part of a sphere. The inner surface 4 and the outer surface 6 of the inner ring 2 are connected to each other by a side wall 7. According to an embodiment not shown, the inner ring 2 may also have a cylindrical sleeve interposed between its inner surface 4 and the outer periphery of the shaft 5. The sleeve may be made of bronze, for example.

The inner ring 2 comprises, for example, a titanium alloy. Alternatively, the ring comprises a nickel alloy or steel.

The outer ring 3 comprises a substantially cylindrical outer surface 8. The outer ring 3 also comprises an inner surface 9 of a spherical shape, more particularly as a part of a spherical shape, which corresponds to the outer surface 6 of the inner ring 2. Thus, the inner ring 2 and the outer ring 3 have three rotational degrees of freedom with respect to each other. The inner surface 9 is connected to the outer surface 8 by a sidewall 10. In the position of fig. 1, the side wall 7 of the inner ring 2 protrudes in axial section on either side of the side wall 10 of the outer ring 3, with the cylindrical surface 4 coaxial with the axis 5.

The outer ring 3 further comprises an annular flange 11 protruding from the outer surface 8 and extending in a radial direction away from the central axis X1. The annular flange has at least one through hole 12 arranged to receive a fastening screw for rigidly fixing said outer ring 3 to the support.

According to the invention, the outer ring 3 is made of two different materials. The outer ring 3 comprises a contact portion 3-1, which is designed to be in sliding contact with the inner ring 2 and is made of a first material. The outer ring further comprises a fastening portion 3-2 made of a second material different from the first material.

The contact portion 3-1 includes an outer surface 8 and an inner surface 9 and a sidewall 10. The contact portion 3-1 is made of a material having a hardness strictly greater than that of the second material. Therefore, the contact portion 3-1 is made of a specific material that performs a rotating function by directly sliding with the inner ring 2. The first material is one of the following materials: bronze, steel, cobalt alloys.

The fastening portion 3-2 comprises a flange 11 and is made of a material which is strictly more elastic than the first material. Therefore, the fastening portion 3-2 is made of a specific material for bearing load and vibration. The second material is one of the following materials: titanium, titanium alloy, aluminum alloy, nickel alloy.

Another advantage of the invention is that the material used for the fastening portion 3-2 is cheaper than the material used for the contact portion 3-1 or indeed for the outer ring which is manufactured as a single piece and is made of a material representing a compromise to requirements. The material used for the fastening portion 3-2 is also lighter than the material used for the contact portion 3-1 or indeed for the outer ring manufactured as a single piece and made of a material representing a compromise to the requirements. This gives a ball joint ring that can optimally perform each of the two functions of rotation and fastening at a lower cost and with a lower weight.

In fig. 2 a second embodiment of the invention is shown, wherein the connecting element comprises a bearing element with roller elements, generally indicated with reference numeral 20, having a central axis X20.

The bearing 20 includes an inner ring 21, an outer ring 22, and a plurality of roller elements 23.

The inner ring 21 has a generally cylindrical inner surface 24, a cylindrical outer surface 25 forming an inner raceway for the roller elements 23, and a sidewall 26 connecting the inner and outer surfaces 24, 25.

The inner ring 21 is made of steel, for example M50.

The outer ring 22 has a generally cylindrical outer surface 27, a cylindrical inner surface 28 forming an outer raceway for the roller elements 23, and a sidewall 29 connecting the outer surface 27 and the inner surface 28.

Advantageously, the external surface 27 comprises two circumferential grooves 30, 31, each housing an O-ring seal (not shown), a fluid film being axially interposed between the two seals housed in said grooves 30, 31, said film being radially captured between said external surface 27 and a surface of a fixed support (not shown) to form means for damping vibrations.

The roller elements 23 are accommodated between said inner and outer raceways 25, 28. In the example shown in fig. 2, the roller elements 23 are cylindrical rollers having axes parallel to the central axis X1. Alternatively, the roller elements may take another form, such as balls or conical rollers.

According to the embodiment shown in fig. 2, the outer ring 22 also has a cage 32 extending axially from the side wall 29 of said outer ring 22.

The cage 32 has a fixing edge 33, which extends substantially radially and is intended to be rigidly fixed to a fixing support (not shown), for example by means of screws passing through the through holes 34 and housed in corresponding threaded holes in said support. The cage 32 also comprises an intermediate portion 35, which is substantially axial, having a plurality of windows 36 distributed circumferentially, so as to give the cage 32 a degree of flexibility to withstand the various types of vibrations of the assembly. According to the embodiment shown in fig. 2, the intermediate portion 35 comprises two axial portions 35-1, 35-2, each having a window 36, the diameter of the axial portion 35-2 being greater than the diameter of the axial portion 35-1. The two axial portions 35-1, 35-2 are connected by a curved portion 35-3. The fastening edge 33 extends radially from the free end of the larger diameter axial portion 35-2.

According to the invention, the outer ring 22 is made of two different materials. The outer ring 22 comprises a contact portion 22-1, which is designed to be in bearing contact with the roller elements 23 and is made of a first material. The outer ring 22 also includes a squirrel cage 32 made of a second material different from the first material.

The contact portion 22-1 includes an exterior surface 27 and an interior surface 28 and a sidewall 29. The contact portion 22-1 is made of a material having a hardness strictly greater than that of the second material. Thus, the contact portion 22-1 is made of a specific material for performing the function of direct bearing support for the roller element 23. The first material is a steel selected from the group consisting of: 100C6, ASP2060, M50, M62.

The cage 32 is made of a material that is strictly more elastic than the first material. Thus, the cage 32 is made of a specific material for withstanding loads and vibrations. The second material is one of the following materials: low carbon steel, medium carbon steel, titanium alloys, aluminum alloys, M50NiL, 32CVD13, and INCONEL 718.

The rings 3 and 22 of both embodiments shown in fig. 1 are made of two different materials. According to the invention, the rings 3 and 22 are manufactured by a method comprising the following steps.

The contact portions 3-1, 22-1 are machined from a rod of the first material and have contact surfaces 9, 28, respectively. The determined size and shape of the contact portions 3-1, 22-1 can be manufactured starting from this step.

Next, the contact portions 3-1, 22-1 thus obtained are mounted in a fixed support so that part of its outer surface is free. The outer surface portion corresponds to a surface on which the fastening portion is to be formed and attached in a subsequent step. Therefore, the outer surface of the side wall 10 of the contact portion 3-1 is free, and the outer surface of the side wall 29 of the contact portion 22-1 is free. According to a particular embodiment of the method, the contact portion is mounted in a fixed support such that only the surface of the side wall 10, 29 is flush with the mounting surface of said support. For this purpose, the contact portions 3-1, 22-1 may be received in recesses of the support. According to a particularly advantageous embodiment, said outer surface portion 10, 29 may be ground so as to be perfectly flush with said mounting surface of the support.

According to a first embodiment of the method, the contact portions 3-1, 22-1 and the support are assembled in a 3D printer. The second material is stored in powder form and the shape of the fastening portions 3-2, 32 is printed on the contact portions 3-1, 22-1, respectively. More specifically, a continuous layer of the second material is deposited on the free surface of the side walls 10, 29 of the contact portions 3-1, 22-1 until the fastening portions 3-2, 22 are formed.

According to the second embodiment, a mold having the shape of the fastening portion is mounted on the contact portions 3-1, 22 so that only the surface of the side wall 10, 29 on which the fastening portion is to be formed is free inside the mold.

The fastening portions 3-2, 32 are formed by injecting powder under vacuum into a closed mould. The shape thus obtained is consolidated by Hot Isostatic Pressing (HIP).

According to other embodiments, the powder of the second material may be melted by electron beam melting, selective laser melting, or by direct metal deposition.

Finally, the fastening portions 3-2, 22 are finally dimensioned by machining. The method for manufacturing the ring 3, 22 may also comprise the step of depositing a surface coating, in particular on the raceway 9, 28.

Furthermore, the technical features of the different embodiments may be combined in their entirety and only in certain cases. Thus, the ball joint can be adapted in terms of cost, performance and user-friendliness.

The articulated parts and bearing elements of the invention in the form of ball joints have been described as examples of embodiments. The invention can be used for any kind of connecting element.