Connector for connecting first and second members

Abstract

A composite swivel ball joint having main body 2 made of reinforcing fibres impregnated in a plastic resin matrix 6b, and ball joint 3 swivelling within housing 4. First fibrous strip 7 or a coating i

Description

Title: Connector for connecting first and second members Technical field of the invention The present invention relates, in a general manner, to connectors used to connect two members to each other. More specifically, the invention relates to a connector, such as a fitting or shackle, comprising a body made of composite material and a ball joint mounted in the body. Prior art Traditionally, in the aeronautical field, use is made of connectors such as metal fittings, for example made of aluminium, titanium or steel. Such connecting pieces serve to connect two members in relative swivelling motion by way of a ball joint interposed between said members and as one with the connecting piece. This is the case for example of a fitting for attachment of a thrust reverser cowl of an aircraft turbine. The use of a connecting piece formed at least partially of composite material, i.e. of polymer material reinforced with fibres such as glass or carbon fibres, is particularly advantageous for fields in which the weight saving is essential, such as for example in aeronautics. Document FR3067073 proposes a connecting piece formed by a body made of composite material with reinforcing fibres embedded in a plastic matrix made of resin such that said reinforcing fibres form, with the resin, plies that are stacked in order to form a laminate. A mounting ring, interposed between the ball joint and the housing of the body in which ball joint is mounted, makes it possible to reduce the impact of the repeated forces generated during the swivelling. However, the integration of the mounting ring is expensive and burdensome, and makes the structure heavier. Another embodiment described in document FR3067073 consists in replacing the mounting ring with a self-lubricating fabric. However, in the event of significant axial and radial loads applied to the body by the ball joint, the resin between said plies at the interface with the ball joint is tensioned. Repeated forces then have the effect of separating the plies, leading to premature delamination of the composite material around the housing formed to receive the ball joint. Summary of the invention The invention therefore aims to remedy these drawbacks and to propose a lightweight and inexpensive connector, which is able to withstand tensile and compressive radial and axial loads in order to offset the risks of delamination of the body of the connector. The invention therefore proposes a connector for connecting first and second members, comprising: a body made of composite material comprising reinforcing fibres embedded in a plastic matrix made of resin, comprising a fastening zone for the first member; a ball joint that is able to move by swivelling in a housing of the body and comprising a bore for the fastening of the second member; a first fibrous strip or a coating having a coefficient of friction less than or equal to 0.1, positioned between the housing and the ball joint, in contact with the ball joint; and a second fibrous strip having a coefficient of friction greater than or equal to 0.2, positioned between the housing and the ball joint, in contact with the housing. Such a configuration makes it possible to conserve a connector weight and compactness that are compatible with an application in the aerospace field while at the same time ensuring, on the one hand, friction properties that are sufficiently low for articulation of the ball joint that Is effective and without risk of delamination under an endurance load and, on the other hand, friction properties that are sufficiently high to protect the body of the connector from any risk of delamination under axial and radial loads. The connector according to the invention is reliable and inexpensive and its service life is optimised. Advantageously, the first and second fibrous strips are positioned in contact with one another. According to an alternative embodiment, in which the first fibrous strip is replaced with a coating, the second fibrous strip and the coating may be positioned in contact with one another. Coating is understood to mean a layer applied by chemical treatment or a layer affixed to an outer surface of the ball joint. Preferably, the first fibrous strip or the coating comprises lubricating particles comprising lubricating fibres impregnated with a binder, such as a resin, and / or at least one solid lubricant, the lubricating particles or the solid lubricant preferably comprising a fluoropolymer, such as polytetrafluoropolymer, graphite, molybdenum sulfide, hexagonal boron nitride or a mixture of these. The lubricating particles make it possible to lower the coefficient of friction of the first fibrous strip and to limit the friction between the body and the ball joint during the swivelling. Preferably, the first fibrous strip comprises structural fibres chosen from glass and / or carbon fibres. The structural fibres The structural fibres make it possible to maintain the lubricating particles, such as fibres, of which the mechanical performance is lower and which could be torn under loading during the relative movement between ball joint and the body of the connector. Advantageously, the second fibrous strip may comprise structural fibres impregnated with a binder, such as a resin, the structural fibres being chosen from glass and / or carbon fibres. The structural fibres make it possible to limit the risk of delamination of the body of the connector. Preferably, the second fibrous strip comprises a composite material identical to the composite material of the body, In order to increase the compatibility between the body and the second fibrous strip. According to one feature, the reinforcing fibres of the body form, with the resin, plies extending perpendicular to the axis of the housing, and the second fibrous strip may have plies extending substantially perpendicular to said plies of the body. This makes it possible to reinforce the structure of the connector and to further limit the separation of the plies of the body of the connector during the swivelling. In one embodiment, the first and second fibrous strips may be fastened to the body such that the ball joint is in motion relative to the assembly formed by the body and the first and second fibrous strips. Such an arrangement is particularly easy to realise, making it easier to manufacture the connector and reducing the manufacturing time thereof. This also makes it possible to integrate any type of ball joint in the body of the connector. According to an alternative, the first fibrous strip or the coating may be fastened to the ball joint and the second fibrous strip may be fastened to the body such that the assembly formed by the ball joint and the first fibrous strip or the coating is in motion relative to the assembly formed by the body and the second fibrous strip. In another embodiment, the second fibrous strip may be fastened to the body by impregnation of the plastic matrix made of resin of the body. According to an alternative, the first and second fibrous strips may be fastened to the body by impregnation of the plastic matrix made of resin of the body. This makes the integration of the first and second fibrous strips easier and makes it possible to consolidate the assembly formed by the body and the first and second fibrous strips. In another alternative embodiment, the first fibrous strip may be fastened to the ball joint by adhesive bonding. In one embodiment, the second fibrous strip may be fastened to the body by adhesive bonding. In another embodiment, the first and second fibrous strips may be fastened to the body by adhesive bonding. In this case, the second fibrous strip may be fastened in contact with the housing of the body, and the first fibrous strip may be fastened in contact with the second fibrous strip. Brief description of the figures Further aims, advantages and features will become apparent from the following description, which is given purely by way of illustration and with reference to the appended drawings, in which: [Fig 1] is a perspective view of a fitting according to one embodiment of the invention. [Fig 2] is a view in transverse cross section of the fitting illustrated in Figure 1. Detailed description of the invention Figures 1 and 2 depict a connector 1 intended to connect first and second members (not shown). In the example illustrated, the connector is a fitting intended for an application in the aerospace field. The connector 1 comprises a body 2 made of composite material having reinforcing fibres embedded in a plastic matrix 6b. The fibres are, advantageously, made of carbon, but may be made of another material, such as glass. The plastic matrix 6b is made of thermosetting resin, for example epoxy, but other materials such as thermoplastic resins, for example PEEK, PEKK, PEAK, may be used. The body 2 of the connector 1 comprises a fastening zone for the first member to be connected, which, in the example illustrated, takes the form of a base 5. Means for fastening the first member to the connector 1 may involve screws or rivets. The connector 1 also comprises a ball joint 3 mounted in a housing 4, of axis XI, of the body 2. The housing 4 is delimited by an inner surface or bore of the body 2. Advantageously, the ball joint 3 is metallic, for example made of titanium, steel, aluminium, bronze or an alloy of these. The bore of the housing 4 is spherical so as to cooperate with the ball joint 3. The ball joint 3, of axis X2, is able to move by swivelling in the housing 4 of the body 2. The connector 1 thus makes it possible to rigidly connect the first and second members while at the same time allowing them to be articulated to each other, by swivelling of the ball joint 3 in the housing 4. The ball joint 3 may be formed of two parts that can be separated in order to allow the mounting of the ball joint 3 in the housing 4. Advantageously, the ball joint 3 has a spherical outer surface 3a intended to cooperate with the housing 4 for the articulation of the ball joint 3, and an inner surface or bore 3b for the fastening of the second member. In the example illustrated, the bore 3b is cylindrical and of axis X2. The reinforcing fibres of the body 2 form, with the resin, plies or sheets 6a. These plies 6a are stacked so as to form a laminate, as is illustrated in Figure 2, which depicts a longitudinal section of the connector 1 on a plane passing through the axis XI and that is parallel to the plies 6a of the body 2. Advantageously, in order to simplify the manufacture of the body 2 of the connector 1, the plies 6a are mutually parallel. In addition, the plies 6a extend over the entire length of the body 2, with the exception of the zone of the housing 4, in which they are partially interrupted in order to obtain the housing 4, for example by removal of material. Furthermore, the connector 1 comprises a first fibrous strip 7 having a coefficient of friction less than or equal to 0.1, positioned between the housing 4 and the ball joint 3, in contact with the ball joint 3. The first fibrous strip 7 with a lubricating function makes it possible to maintain an endurance load between the body 2 and the spherical joint 2 by reducing the friction at the interface with the spherical joint 3, and this also reduces the risks of delamination. The first fibrous strip 7 may comprise lubricating particles comprising lubricating fibres impregnated with a binder, such as a resin. The first fibrous strip 7 may also comprise, in addition to or instead of the lubricating particles, at least one solid lubricant. For example, the lubricating particles or the solid lubricant may comprise a fluoropolymer, such as polytetrafluoropolymer, graphite, molybdenum sulfide, hexagonal boron nitride or a mixture of these. Preferably, the first fibrous strip 7 also comprises structural fibres, in particular in addition to the lubricating particles, in particular the lubricating fibres. The structural fibres make it possible to reinforce the first fibrous strip 7, by maintaining the lubricating particles, such as fibres, of which the mechanical performance is lower and which could be torn under loading during the relative movement between ball joint 3 and the body 2 of the connector 1. The structural fibres also make it possible to withstand the opening loads that are transmitted to the body 2 of the connector 1 during the pivoting of the ball joint 3 bearing the second member and tend to separate the plies 6a of the body 2. The structural fibres of the first fibrous strip 7 may be chosen from glass fibres, carbon fibres or a mixture of these. Advantageously, the first fibrous strip 7 may be a self-lubricating fabric. According to an alternative, the first fibrous strip 7 may be replaced with a coating, applied at least partially to the outer surface 3a of the ball joint 3, having a coefficient of friction less than or equal to 0.1. The coating may be a layer obtained by chemical treatment of the outer surface of the ball joint 3, or a layer affixed to the outer surface of the ball joint 3, such as forming a liner. Preferably, the coating is applied to all of the outer surface 3a of the ball joint 3. The coating may comprise lubricating particles comprising lubricating fibres impregnated with a binder, such as a resin. The coating may also comprise, in addition to or instead of the lubricating particles, at least one solid lubricant. For example, the lubricating particles or the solid lubricant may comprise a fluoropolymer, such as polytetrafluoropolymer, graphite, molybdenum sulfide, hexagonal boron nitride or a mixture of these. Preferably, the coating also comprises structural particles, such as fibres, for example glass fibres, carbon fibres or a mixture of these. In addition, the connector 1 comprises a second fibrous strip 8 having a coefficient of friction greater than or equal to 0.2, positioned between the housing 4 and the ball joint 3, in contact with the housing 4. In the example illustrated, the first and second fibrous strips 7 and 8 are positioned in contact with one another. The first fibrous strip 7 comprises an inner surface in contact with the outer surface 3a of the ball joint 3 and an opposite outer surface in contact with an inner surface of the second fibrous strip 8. The second fibrous strip 8 comprises an inner surface in contact with the outer surface of the first fibrous strip 7, or of the coating, and an outer surface in contact with the housing 4. According to an alternative embodiment, in which the first fibrous strip 7 is replaced with a coating, the second fibrous strip 8 and the coating may be positioned in contact with one another. The coating comprises an inner surface in contact with the outer surface 3a of the ball joint 3 and an opposite outer surface in contact with an inner surface of the second fibrous strip 8. The second fibrous strip 8 comprises an inner surface in contact with the outer surface of the coating and an outer surface in contact with the housing 4. Preferably, the second fibrous strip 8 comprises structural fibres impregnated with a binder, such as a resin. The structural fibres may be chosen from glass fibres, carbon fibres or a mixture of these. The second fibrous strip 8 may, advantageously, comprise a composite material identical to the composite material of the body 2, in order to improve the compatibility between the body 2 and the second fibrous strip 8. In the example illustrated, the reinforcing fibres of the body 2 form, with the resin, plies 6a extending perpendicular to the axis XI of the housing 4, at least in the zone of the body 2 around the housing 4 extending over a few millimetres or tens of millimetres, and this makes it possible to increase the tensile and compressive strength. The second fibrous strip 8 may also have plies. Preferably, the plies of the second fibrous strip 8 extend transversely along the fibrous strip 8, so as to extend substantially perpendicular to the plies 6a of the body. The first fibrous strip 7 may also have at least one ply. The thickness of the first fibrous strip 7, the thickness of the coating and the thickness of the second fibrous strip 8 are, preferably,of the order of millimetres, between 0.5 and 5 mm. For example, the first fibrous strip 7 and the second fibrous strip 8 respectively have a proportion of 10% and 90% plies. This ratio may be adjusted as a function of the required ratio between swivelling endurance stress and static load. In one embodiment, the first and second fibrous strips 7 and 8 may be fastened to the body 2. In this way, the ball joint 3 is in motion relative to the assembly formed by the body 2 and the first and second fibrous strips. In an alternative embodiment, the first fibrous strip 7, or the coating, may be fastened to the ball joint 3, while the second fibrous strip 8 may be fastened to the body 2. In this way, the assembly formed by the ball joint 3 and the first fibrous strip 7, or the coating, is in motion relative to the assembly formed by the body 2 and the second fibrous strip 8. Preferably, the fastening of the second fibrous strip 8 or the fastening of the first and second fibrous strips 7 and 8 to the body 2 is realised by impregnation of the plastic matrix 6b made of resin of the body 2. As an alternative, the first fibrous strip 7, the second fibrous strip 8 or the first and second fibrous strips 7, 8 may be fastened by adhesive bonding. According to one example, the second fibrous strip 8 may be fastened in contact with the housing 4 by means of an adhesive, and the first fibrous strip 7 may be fastened in contact with the second fibrous strip 8, also by means of adhesive. According to another example, the second fibrous strip 8 may be fastened in contact with the housing 4 by means of an adhesive, and the first fibrous strip 7 may be fastened in contact with the ball joint 3, also by means of adhesive. In the example illustrated, the connector 1 is configured to connect two members. As an alternative, the connector 1 may be implemented to connect three or more members to each other. Furthermore, the invention may be applied to a type of connector other than a fitting, for example a rod end or a shackle, for example also for an application in the aerospace field or any other technical field.

Claims

1. Connector (1) for connecting first and second members, comprising: a body (2) made of composite material comprising reinforcing fibres embedded in a plastic matrix (6b) made of resin, comprising a fastening zone for the first member;a ball joint (3) that is able to move by swivelling in a housing (4) of the body (2) and comprising a bore (3b) for the fastening of the second member;a first fibrous strip (7) or a coating having a coefficient of friction less than or equal to 0.1, positioned between the housing (4) and the ball joint (3), in contact with the ball joint (3); anda second fibrous strip (8) having a coefficient of friction greater than or equal to 0.2, positioned between the housing (4) and the ball joint (3), in contact with the housing (4).

2. Connector according to Claim 1, wherein the first fibrous strip (7) or the coating comprises lubricating particles comprising lubricating fibres impregnated with a binder, such as a resin, and / or at least one solid lubricant, the lubricating particles or the solid lubricant preferably comprising a fluoropolymer, such as polytetrafluoropolymer, graphite, molybdenum sulfide, hexagonal boron nitride or a mixture of these.

3. Connector according to Claim 2, wherein the first fibrous strip (7) comprises structural fibres chosen from glass and / or carbon fibres.

4. Connector according to any one of Claims 1 to 3, wherein the second fibrous strip (8) comprises structural fibres impregnated with a binder, such as a resin, the structural fibres being chosen from glass and / or carbon fibres.

5. Connector according to any one of the preceding claims, wherein the second fibrous strip (8) comprises a composite material identical to the composite material of the body (2).

6. Connector according to any one of the preceding claims, wherein the reinforcing fibres of the body (2) form, with the resin, plies (6a) extending perpendicular to the axis of the housing (4), and the second fibrous strip (8) has plies extending substantially perpendicular to said plies (6a) of the body (2).

7. Connector according to any one of the preceding claims, wherein the first and second fibrous strips (7, 8) are positioned in contact with one another, or the coating and the second fibrous strip (8) are positioned in contact with one another.5 8. Connector according to any one of the preceding claims, wherein thefirst and second fibrous strips (7, 8) are fastened to the body (2) such that the ball joint (3) is in motion relative to the assembly formed by the body (2) and the first and second fibrous strips (7, 8).

9. Connector according to any one of the preceding claims, wherein the 10 second fibrous strip (8) or the first and second fibrous strips (7, 8) are fastened to the body (2) by impregnation of the plastic matrix (6b) made of resin of the body (2).

10. Connector according to any one of the preceding claims, wherein the first fibrous strip (7) and / or the second fibrous strip (8) are fastened to the body 15 (2) or to the ball joint (3) by an adhesive.Application No: GB2411157.7Examiner: Ian ChoiClaims searched: 1-10Date of search: 18 December 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance A - GB 2021702 A (INCOM INT INC) See especially figures 1, 2, 4-8 and 10, page 2 lines 51-53, page 3 lines 3-20, page 3 lines 53-117. A - US 2009 / 0154990 Al (JULLIERE) See especially figures and A - GB 1233103 A (NATIONAL RESEARCH DEVELOPMENT CORP) See especially figures lb-3b, page 1 lines 12-29, and page 3 lines 25-76. A - GB 2564558 A (SKF AEROSPACE FRANCE SAS) See especially figures and page 3 lines 24-29. A - US 2008 / 0104845 Al (LEE et al.) See especially figures 1 and 4 and paragraphs 35 and 36.Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of before the filing date of this invention. same category. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From F16C 0011 / 06 01 / 01 / 2006 F16C 0023 / 04 01 / 01 / 2006 F16C 0033 / 08 01 / 01 / 2006 F16C 0033 / 12 01 / 01 / 2006 F16C 0033 / 20 01 / 01 / 2006 F16C 0035 / 02 01 / 01 / 2006

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