Finite element modeling method for an aviation electrical connector housing and rear attachment

Abstract

The application discloses a finite element modeling method for an aviation electric connector shell and a rear accessory, which is characterized in that: key parts such as the shell outer thread and the sleeve nut inner thread in the complex structure of the aviation electric connector are accurately modeled, and other parts which have less influence on the structure stress and force are simplified and omitted as much as possible; the finite element modeling can be carried out on the aviation electric connector shell and the rear accessory with different materials, thread types, shape geometric parameters and tightening degrees, and a reliable foundation is provided for subsequent quantitative numerical calculation, so that the stress field and the force field of the electric connector under the conditions of the tightening process and dynamic excitation can be obtained.

Description

Technical Field

[0001] This invention belongs to the technical field of aviation electrical connector modeling, specifically relating to a finite element modeling method for aviation electrical connector housings and accessories. Background Technology

[0002] Aviation electrical connectors consist of a housing and a rear accessory structure, which, when connected, protect the wiring harness. The connection between the housing and the rear accessory is achieved using threads. During connector assembly, a specific force needs to be applied to the threads; that is, a corresponding tightening torque is applied based on the model and size. The tightening torque cannot be too high, otherwise it increases assembly difficulty and may damage the structure. The tightening torque also cannot be too low, otherwise the rear accessory may loosen under dynamic conditions, losing its protective function. Therefore, the tightening torque must be appropriate. To determine the tightening torque value for the aviation electrical connector's rear accessory, it is necessary to examine the characteristic relationship between the tightening torque and structural stress and dynamic environmental response as a basis. Due to the relatively complex structure of the connector housing and rear accessory, it is difficult to obtain the characteristic relationship when the connector housing and rear accessory are connected and tightened through theoretical calculations; actual testing is costly, difficult to measure, and the measurement results are not accurate enough.

[0003] Therefore, in view of the above-mentioned problems in the theoretical calculation and actual test of the connection model of aviation electrical connector and rear accessory in the prior art, the present invention discloses a finite element modeling method for aviation electrical connector housing and rear accessory. Summary of the Invention

[0004] This invention discloses a finite element modeling method for aviation electrical connector housings and accessories. It can perform finite element modeling for aviation electrical connector housings and accessories with different materials, thread types, shape geometry parameters, and tightening degrees, providing a reliable basis for subsequent quantitative numerical calculations, so as to obtain the stress field and force field of the electrical connector under tightening process and dynamic excitation conditions.

[0005] This invention is achieved through the following technical solution:

[0006] A finite element modeling method for an aircraft electrical connector housing and its rear accessories includes the following steps:

[0007] Step 1: Decompose the aviation electrical connector into a housing model, an ear clip model, and an outer nut model, and perform solid disassembly of the structure of the housing model, ear clip model, and outer nut model;

[0008] Step 2: Based on the entity splitting results, establish the shell model;

[0009] Step 3: Based on the solid features on the shell model that mate with the ear clip model, establish the ear clip model;

[0010] Step 4: Based on the solid features of the shell model and the outer nut model that mate, and based on the solid features of the ear clip model that mate with the outer nut model, establish the outer nut model;

[0011] Step 5: Set the material parameters and contact parameters for the shell model, ear clip model, and outer nut model;

[0012] Step 6: Mesh the shell model, ear clip model, and outer nut model, and set boundary conditions.

[0013] To better realize the present invention, step 2 further includes:

[0014] Step 2.1: Decompose the shell model into the shell external thread entity, the shell base entity, and the shell gear entity;

[0015] Step 2.2: Discretize the circumferential profile of the external thread of the shell external thread entity by circumferential equal-length segmentation to convert the circumferential profile of the external thread into several straight segments connected in sequence; Discretize the external thread entity of the shell external thread entity by axial equal-length segmentation to obtain several discrete layers.

[0016] Step 2.3: Based on the straight line segments, additive and subtractive modeling is used to obtain the single-pitch shell external thread entity. The single-pitch shell external thread entity is then copied axially to obtain the entire shell external thread entity.

[0017] Step 2.4: Obtain the shell base solid by stretching additive manufacturing at one end of the external threaded solid of the shell;

[0018] Step 2.5: Create a circumferential profile of the meshing tooth at the other end of the external thread entity of the shell, and create a single meshing tooth of the shell on the circumferential profile of the meshing tooth. Copy the single meshing tooth of the shell at equal intervals along the circumferential profile of the meshing tooth to obtain the entire meshing tooth entity of the shell.

[0019] To better realize the present invention, step 2.2 further includes:

[0020] Step 2.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points on the circumferential profile of the external thread at equal intervals;

[0021] Step 2.2.2: Calculate the discrete distance between each discrete point of the external thread and the center of the circumferential profile of the external thread;

[0022] Step 2.2.3: Based on the discrete distance of the external thread, calculate the polar coordinates of the corresponding discrete point of the external thread relative to the center of the circumferential profile of the external thread. Connect the discrete points of the external thread sequentially within the circumferential range of 0-180° to form a half profile of the external thread. Then, copy the half profile of the external thread symmetrically to obtain the circumferential profile of the external thread after circumferential equal-length segmented discretization.

[0023] Step 2.2.4: Set the axial division parameter M so that the pitch of the external thread of the housing can be divided by M, and 2N can be divided by M.

[0024] Step 2.2.5: Along the axial direction of the external threaded body of the housing, every... The distance / M is used to divide the external threaded solid of the shell into discrete layers. This indicates the pitch of the external threaded entity of the housing.

[0025] To better realize the present invention, the calculation formula for the discrete distance of the external thread is further as follows:

[0026] ;

[0027] Where: R represents the discrete distance of the external thread between the discrete point of the external thread and the center of the circumferential profile of the external thread; Indicates the major diameter of the external thread on the housing; Indicates the reference thread height of the external thread of the housing; Indicates the diameter of the root circle of the external thread on the housing; Indicates the pitch of the external thread on the housing; This represents the angle between the line connecting the discrete point of the external thread and the center of the circumferential profile of the external thread and the positive direction of the horizontal axis. Indicates the first angle threshold; This represents the second angle threshold.

[0028] To better realize the present invention, step 3 further includes:

[0029] Step 3.1: Disassemble the ear clip model into the ear clip teeth solid, the ear clip base solid, and the ear clip handle solid;

[0030] Step 3.2: Extract the tooth profile of the shell tooth entity, and obtain the ear clip tooth entity that meshes with the shell tooth entity and faces the opposite direction by filling additive manufacturing;

[0031] Step 3.3: Build an ear clip base entity by stretching at the end of the ear clip tooth entity away from the shell model, and build an ear clip groove entity on the ear clip base entity;

[0032] Step 3.4: Build ear clip handle entities symmetrically on both sides of the end of the ear clip base entity that is away from the shell model.

[0033] To better realize the present invention, step 3.2 further includes:

[0034] Step 3.2.1: Extract any two adjacent single-shell teeth from the shell tooth entity, and extract the peaks and troughs of the region between the two single-shell teeth;

[0035] Step 3.2.2: In the space between the crest and trough, based on the tooth profile of the shell tooth entity, a single ear clip tooth that meshes with the shell tooth entity and faces the opposite direction is obtained by filling additive manufacturing.

[0036] Step 3.2.3: Copy the single tooth of the ear clip along the circumferential direction to obtain the entire ear clip tooth entity.

[0037] To better realize the present invention, step 4 further includes:

[0038] Step 4.1: Disassemble the outer nut model into the nut internal thread solid, the nut base solid, and the nut internal boss solid;

[0039] Step 4.2: Extract the horizontal interface between the first pitch and the second pitch on the external thread entity of the shell, establish the circumferential profile of the internal thread on the horizontal interface, and perform circumferential equal-length segment discretization on the internal thread circumferential profile to convert the internal thread circumferential profile into several straight segments connected in sequence; perform axial equal-length segment discretization on the internal thread entity of the nut to obtain several discrete layers.

[0040] Step 4.3: Based on the straight line segments, use the contour connection method to add and subtract materials to obtain the single-pitch nut internal thread entity. Axially copy the single-pitch nut internal thread entity to obtain the entire nut internal thread entity.

[0041] Step 4.4: Build a nut base cylinder entity at one end of the nut's internal thread entity;

[0042] Step 4.5: Create the inner boss entity of the nut based on the contour of the ear clip groove entity inside the nut base cylinder entity.

[0043] To better realize the present invention, step 4.2 further includes:

[0044] Step 4.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points of the internal thread at equal intervals on the circumferential profile of the internal thread;

[0045] Step 4.2.2: Calculate the discrete distance between each discrete point of the internal thread and the center of the circumferential profile of the internal thread;

[0046] Step 4.2.3: Based on the internal thread discrete distance, calculate the polar coordinates of the corresponding internal thread discrete point relative to the center of the internal thread circumferential profile. Connect the internal thread discrete points sequentially within the circumferential range of 0-180° to form an internal thread half profile. Then, axially symmetrically copy the internal thread half profile to obtain the internal thread circumferential profile after circumferential equal-length segmented discreteness.

[0047] Step 4.2.4: Set the axial division parameter M so that the pitch of the internal thread of the nut can be divided by M, and 2N can be divided by M.

[0048] Step 4.2.5: Along the axial direction of the nut's internal thread, at intervals... The distance / M is used to divide the internal thread of the nut into discrete layers. This indicates the pitch of the internal thread of the nut.

[0049] To better realize the present invention, the calculation formula for the discrete distance of the internal thread is further as follows:

[0050] ;

[0051] Where: r represents the discrete distance of the internal thread between the discrete point of the internal thread and the center of the circumferential profile of the internal thread; Indicates the major diameter of the nut's internal thread; Indicates the reference thread height of the nut's internal thread; Indicates the adjustment parameter; Indicates the pitch of the internal thread of the nut; This represents the angle between the line connecting the discrete point of the internal thread and the center of the circumferential profile of the internal thread and the positive direction of the horizontal axis. Indicates the first angle threshold; Indicates the second angle threshold; This represents the difference between the major diameter of the nut's internal thread and twice the working height of the internal thread.

[0052] To better realize the present invention, the adjustable incremental distance is further increased for the discrete distance of the internal thread.

[0053] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0054] (1) This invention overcomes the problem that it is difficult to theoretically calculate the force and stress in the tightening of the housing and rear accessory structure of the aviation electrical connector. It replaces the traditional destructive test method and provides the necessary conditions for numerical calculation based on the finite element modeling method. It can obtain information with sufficient accuracy on the characteristic relationship between tightening torque and structural stress and dynamic environmental response while significantly reducing test costs.

[0055] (2) The present invention accurately models the key parts such as the outer thread of the housing and the inner thread of the outer nut in the complex structure of the aviation electrical connector, and simplifies and omits other parts that have little impact on structural stress and force as much as possible, which has good economic efficiency;

[0056] (3) The present invention can easily change the model and material of the aviation electrical connector housing and rear accessories, and is applicable to a variety of models and materials, and has strong practicality and certain universal applicability. Attached Figure Description

[0057] Figure 1 This is a schematic diagram of the process steps of the present invention;

[0058] Figure 2 This is a schematic diagram after the thread profile has been discretized into segments.

[0059] Figure 3 This is a schematic diagram of a single-pitch external thread on a housing.

[0060] Figure 4 This is a schematic diagram of the external threaded body of the housing;

[0061] Figure 5 This is a schematic diagram of the shell's meshing teeth.

[0062] Figure 6 This is a schematic diagram of the shell model;

[0063] Figure 7 A schematic diagram of the ear clip teeth;

[0064] Figure 8 This is a schematic diagram of an ear clip model;

[0065] Figure 9 This is a schematic diagram of the internal thread of a single-pitch nut.

[0066] Figure 10 A schematic diagram of the solid internal thread of a nut.

[0067] Figure 11 This is a schematic diagram of the outer nut model;

[0068] Figure 12 A schematic diagram of the mesh generation process for an aviation electrical connector;

[0069] Figure 13 This is a schematic diagram showing the variation of maximum stress with tightening torque in an aviation electrical connector model.

[0070] Figure 14 This is a schematic diagram showing the location of maximum stress in an aviation electrical connector model.

[0071] Figure 15 This is a schematic diagram showing the location of the failure point due to the maximum stress when the aviation electrical connector is actually tightened. Detailed Implementation

[0072] Example 1:

[0073] This embodiment presents a finite element modeling method for an aviation electrical connector housing and its rear accessories, such as... Figure 1 As shown, it includes the following steps:

[0074] Step 1: Decompose the aviation electrical connector into a housing model, an ear clip model, and an outer nut model, and perform solid disassembly of the structure of the housing model, ear clip model, and outer nut model;

[0075] Step 2: Based on the entity splitting results, establish the shell model;

[0076] Step 3: Based on the solid features on the shell model that mate with the ear clip model, establish the ear clip model;

[0077] Step 4: Based on the solid features of the shell model and the outer nut model that mate, and based on the solid features of the ear clip model that mate with the outer nut model, establish the outer nut model;

[0078] Step 5: Set the material parameters and contact parameters for the shell model, ear clip model, and outer nut model;

[0079] Step 6: Mesh the shell model, ear clip model, and outer nut model, and set boundary conditions.

[0080] Step 2 specifically includes:

[0081] Step 2.1: Decompose the shell model into the shell external thread entity, the shell base entity, and the shell gear entity;

[0082] Step 2.2: Discretize the circumferential profile of the external thread of the shell external thread entity by circumferential equal-length segmentation to convert the circumferential profile of the external thread into several straight segments connected in sequence; Discretize the external thread entity of the shell external thread entity by axial equal-length segmentation to obtain several discrete layers.

[0083] Step 2.3: Based on the straight line segments, additive and subtractive modeling is used to obtain the single-pitch shell external thread entity. The single-pitch shell external thread entity is then copied axially to obtain the entire shell external thread entity.

[0084] Step 2.4: Obtain the shell base solid by stretching additive manufacturing at one end of the external threaded solid of the shell;

[0085] Step 2.5: Create a circumferential profile of the meshing tooth at the other end of the external thread entity of the shell, and create a single meshing tooth of the shell on the circumferential profile of the meshing tooth. Copy the single meshing tooth of the shell at equal intervals along the circumferential profile of the meshing tooth to obtain the entire meshing tooth entity of the shell.

[0086] Step 2.2 specifically includes:

[0087] Step 2.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points on the circumferential profile of the external thread at equal intervals;

[0088] Step 2.2.2: Calculate the discrete distance between each discrete point of the external thread and the center of the circumferential profile of the external thread;

[0089] Step 2.2.3: Based on the discrete distance of the external thread, calculate the polar coordinates of the corresponding discrete point of the external thread relative to the center of the circumferential profile of the external thread. Connect the discrete points of the external thread sequentially within the circumferential range of 0-180° to form a half profile of the external thread. Then, copy the half profile of the external thread symmetrically to obtain the circumferential profile of the external thread after circumferential equal-length segmented discretization.

[0090] Step 2.2.4: Set the axial division parameter M so that the pitch of the external thread of the housing can be divided by M, and 2N can be divided by M.

[0091] Step 2.2.5: Along the axial direction of the external threaded body of the housing, every... The distance / M is used to divide the external threaded solid of the shell into discrete layers. This indicates the pitch of the external threaded entity of the housing.

[0092] The formula for calculating the discrete distance of the external thread is as follows:

[0093] ;

[0094] Where: R represents the discrete distance of the external thread between the discrete point of the external thread and the center of the circumferential profile of the external thread; Indicates the major diameter of the external thread on the housing; Indicates the reference thread height of the external thread of the housing; Indicates the diameter of the root circle of the external thread on the housing; Indicates the pitch of the external thread on the housing; This represents the angle between the line connecting the discrete point of the external thread and the center of the circumferential profile of the external thread and the positive direction of the horizontal axis. Indicates the first angle threshold; This represents the second angle threshold.

[0095] Step 3 specifically includes:

[0096] Step 3.1: Disassemble the ear clip model into the ear clip teeth solid, the ear clip base solid, and the ear clip handle solid;

[0097] Step 3.2: Extract the tooth profile of the shell tooth entity, and obtain the ear clip tooth entity that meshes with the shell tooth entity and faces the opposite direction by filling additive manufacturing;

[0098] Step 3.3: Build an ear clip base entity by stretching at the end of the ear clip tooth entity away from the shell model, and build an ear clip groove entity on the ear clip base entity;

[0099] Step 3.4: Build ear clip handle entities symmetrically on both sides of the end of the ear clip base entity that is away from the shell model.

[0100] Step 3.2 specifically includes:

[0101] Step 3.2.1: Extract any two adjacent single-shell teeth from the shell tooth entity, and extract the peaks and troughs of the region between the two single-shell teeth;

[0102] Step 3.2.2: In the space between the crest and trough, based on the tooth profile of the shell tooth entity, a single ear clip tooth that meshes with the shell tooth entity and faces the opposite direction is obtained by filling additive manufacturing.

[0103] Step 3.2.3: Copy the single tooth of the ear clip along the circumferential direction to obtain the entire ear clip tooth entity.

[0104] Step 4 specifically includes:

[0105] Step 4.1: Disassemble the outer nut model into the nut internal thread solid, the nut base solid, and the nut internal boss solid;

[0106] Step 4.2: Extract the horizontal interface between the first pitch and the second pitch on the external thread entity of the shell, establish the circumferential profile of the internal thread on the horizontal interface, and perform circumferential equal-length segment discretization on the internal thread circumferential profile to convert the internal thread circumferential profile into several straight segments connected in sequence; perform axial equal-length segment discretization on the internal thread entity of the nut to obtain several discrete layers.

[0107] Step 4.3: Based on the straight line segments, use the contour connection method to add and subtract materials to obtain the single-pitch nut internal thread entity. Axially copy the single-pitch nut internal thread entity to obtain the entire nut internal thread entity.

[0108] Step 4.4: Build a nut base cylinder entity at one end of the nut's internal thread entity;

[0109] Step 4.5: Create the inner boss entity of the nut based on the contour of the ear clip groove entity inside the nut base cylinder entity.

[0110] Step 4.2 specifically includes:

[0111] Step 4.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points of the internal thread at equal intervals on the circumferential profile of the internal thread;

[0112] Step 4.2.2: Calculate the discrete distance between each discrete point of the internal thread and the center of the circumferential profile of the internal thread;

[0113] Step 4.2.3: Based on the internal thread discrete distance, calculate the polar coordinates of the corresponding internal thread discrete point relative to the center of the internal thread circumferential profile. Connect the internal thread discrete points sequentially within the circumferential range of 0-180° to form an internal thread half profile. Then, axially symmetrically copy the internal thread half profile to obtain the internal thread circumferential profile after circumferential equal-length segmented discreteness.

[0114] Step 4.2.4: Set the axial division parameter M so that the pitch of the internal thread of the nut can be divided by M, and 2N can be divided by M.

[0115] Step 4.2.5: Along the axial direction of the nut's internal thread, at intervals... The distance / M is used to divide the internal thread of the nut into discrete layers. This indicates the pitch of the internal thread of the nut.

[0116] The formula for calculating the discrete distance of the internal thread is as follows:

[0117] ;

[0118] Where: r represents the discrete distance of the internal thread between the discrete point of the internal thread and the center of the circumferential profile of the internal thread; Indicates the major diameter of the nut's internal thread; Indicates the reference thread height of the nut's internal thread; Indicates the adjustment parameter; Indicates the pitch of the internal thread of the nut; This represents the angle between the line connecting the discrete point of the internal thread and the center of the circumferential profile of the internal thread and the positive direction of the horizontal axis. Indicates the first angle threshold; Indicates the second angle threshold; This represents the difference between the major diameter of the nut's internal thread and twice the working height of the internal thread. The adjustable increment distance is added to the discrete distance of the internal thread.

[0119] Example 2:

[0120] This embodiment discloses a finite element modeling method for an aviation electrical connector housing and its rear accessories. It further optimizes the method based on Embodiment 1, and models the housing model as follows:

[0121] The shell model is divided into a shell external thread entity, a shell base entity, and a shell gear entity. A circumferential division parameter N is set, where 180° is divisible by N. Based on the division parameter N, 2N discrete points are established at equal intervals on the circumferential profile of the external thread. The discrete distance between each discrete point and the center of the circumferential profile is calculated. Based on this distance, the polar coordinates of the corresponding discrete point relative to the center of the circumferential profile are calculated. The discrete points are then connected sequentially within the circumferential range of 0-180° to form a half-profile of the external thread. The half-profile is then axially replicated to obtain the circumferential profile of the external thread after segmentation. An axial division parameter M is set, where the pitch of the shell external thread entity is divisible by M, and 2N is divisible by M. Along the axial direction of the shell external thread entity, every... The distance / M is used to divide the external threaded solid of the shell into discrete layers. This represents the pitch of the external thread of the housing; here, N=24 and M=16.

[0122] The formula for calculating the discrete distance of the external thread is as follows:

[0123] ;

[0124] Where: R represents the discrete distance of the external thread between the discrete point of the external thread and the center of the circumferential profile of the external thread; Indicates the major diameter of the external thread on the housing; Indicates the reference thread height of the external thread of the housing; Indicates the diameter of the root circle of the external thread on the housing; Indicates the pitch of the external thread on the housing; This represents the angle between the line connecting the discrete point of the external thread and the center of the circumferential profile of the external thread and the positive direction of the horizontal axis. Indicates the first angle threshold; This represents the second angle threshold.

[0125] in: ; ; ; .

[0126] In the DesignModeler module of the finite element software Ansys Workbench, a plane is created using the Plane function. A sketch is then created on the plane using the Sketch function. Points and lines are drawn and copied on the sketch to obtain the circumferential profile of the external thread of the housing. Following the above steps, the circumferential profile of the external thread is transformed from a curved profile into multiple connected straight line segments, as shown in the image. Figure 2 As shown, the larger the partitioning parameter N, the closer the discretized external thread circumferential profile is to its theoretical analytical shape. An appropriate value of N can be selected according to the accuracy requirements of the finite element model.

[0127] like Figure 3 As shown, a single-pitch shell external thread solid is obtained by additive and subtractive modeling based on straight line segments using contour connection. That is, starting from the first circumferential contour of the external thread, the single-pitch shell external thread is obtained through contour connection additive modeling. The single-pitch shell external thread solid is then axially copied to obtain the entire shell external thread solid.

[0128] In the DesignModeler module of the finite element software Ansys Workbench, a single-pitch housing external thread was obtained through additive manufacturing using the Skin function. A plane was created using the Plane function, and a sketch was drawn on the plane using the Sketch function to obtain the subtractive circular profile. Subsequently, the Extrude function was used to subtract material, resulting in a solid single-pitch housing external thread. The diameter of the subtractive circular profile was 9.2 mm, leaving a certain distance from the minor diameter of the external thread (10.39 mm). Using the solid single-pitch housing external thread as the geometric datum, the Pattern function was used in the DesignModeler module of Ansys Workbench to obtain the following additive manufacturing process using axial copying: Figure 4 The entire external threaded body of the housing is shown.

[0129] like Figure 5 As shown, on one end face of the shell external thread entity perpendicular to the axial direction, a set of concentric circles with diameters of 9.2 mm and 10 mm are drawn as geometric references. The meshing base entity is obtained by extrusion additive manufacturing, and the height of the meshing base entity is 1.5 mm. A meshing circumferential profile is established at one end of the meshing base entity, and a shell single meshing tooth with a trapezoidal cross-section is established on the meshing circumferential profile. The height of the shell single meshing tooth is 1 mm, and the circumferential span is 15°.

[0130] A single shell tooth is additively replicated by rotating equidistantly along its circumferential contour to obtain a shell tooth entity. Since the circumferential span of a single shell tooth is 15°, the number of shell tooth entities is 360 / 15 = 24.

[0131] On the other end face of the shell's external threaded solid perpendicular to the axial direction, a set of concentric circles with diameters of 9.2 mm and 11.4 mm are drawn as geometric references. The shell base solid is obtained by extrusion additive manufacturing, with a height of 1 mm. A square shell base cross-sectional profile is drawn on the surface of the shell base solid perpendicular to the axial direction, forming the mounting plate in the electrical connector shell. The concentric circle solid is then attached to establish the shell base solid. Specifically, in the DesignModeler module of the finite element software AnsysWorkbench, a plane is created using the Plane function, a sketch is created in the plane using the Sketch function, and the concentric circle profile is drawn. Then, the Extrude function is used for additive manufacturing to obtain the shell base solid. Similarly, the Plane, Sketch, and Extrude functions are used to obtain... Figure 6 The mounting plate and housing base are shown.

[0132] Furthermore, the peaks and troughs of the shell meshing entity are rounded. The peaks are rounded with a radius of 0.55 mm, and the troughs are rounded with a radius of 0.35 mm. That is, the shell meshing entity is obtained by using the FBlend function in the DeisgnModeler module of the finite element software Ansys Workbench.

[0133] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again.

[0134] Example 3:

[0135] This embodiment discloses a finite element modeling method for an aviation electrical connector housing and its rear accessories. It further optimizes the method based on Embodiment 1 by modeling the ear clip model:

[0136] Extract any two adjacent single-shell teeth from the shell tooth entity, and extract the crests and troughs in the region between the two single-shell teeth. Within the space between the crests and troughs, based on the tooth profile of the shell tooth entity, obtain ear clip single teeth that mesh with the shell tooth entity and face opposite directions through infill additive manufacturing.

[0137] In the DesignModeler module of the finite element software AnsysWorkbench, the Skin function is used to fill additive materials to obtain a single tooth on the ear clip, and then the Pattern function is used to circumferentially replicate the additive material to obtain, as shown below. Figure 7 The ear clip teeth shown are physical objects.

[0138] On the bottom surface of the ear clip teeth solid perpendicular to the axis, a set of concentric circles with diameters of 9.2 mm and 10.6 mm are drawn as geometric references. The ear clip base solid is obtained by additive manufacturing through extrusion, and the height of the ear clip base solid is 5 mm. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, a plane is created using the Plane function, a sketch is created in the plane using the Sketch function to draw the concentric circle outline, and then the ear clip base solid is obtained by additive manufacturing using the Extrude function.

[0139] Then, a set of concentric circles with diameters of 9.9 mm and 10.6 mm, respectively, are drawn on a surface perpendicular to the axis and 3 mm away from the bottom surface of the ear clip tooth solid as a geometric reference. The ear clip groove solid is obtained by subtracting material through 1 mm extrusion. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, a plane is created using the Plane function, a sketch is created on the plane using the Sketch function to draw the concentric circle outline, and then the Extrude function is used to obtain the desired result. Figure 8 The ear clip groove shown is a physical object.

[0140] On the end face of the ear clip base solid perpendicular to the axis, a 15° sector is cut to obtain the sector shape of the base end face. On a plane perpendicular to the axis and 11mm away from the end face of the ear clip base solid, a rectangle with a length and width of 3.6mm × 3mm is drawn. Using the sector shape and rectangle of the base end face as geometric references, the ear clip handle solid prototype is formed by additive manufacturing through connection. Specifically, in the DesignModeler module of the finite element software AnsysWorkbench, two planes are created using the Plane function, and two sketches are created in the two planes using the Sketch function, respectively, to draw the 15° sector cut and the rectangular outline. Then, the Skin function is used to connect and additively manufacture to obtain the ear clip handle solid prototype. Then, an ear end with a radius of 3.5mm is created on the end face of the ear clip handle solid prototype and additively manufactured by connection to form a single-sided ear clip handle solid. On the single-sided ear clip handle solid end, a concentric circle with a radius of 2mm is drawn, and a hole is formed by subtractive manufacturing through extrusion. Using a single ear clip handle solid as the geometric reference, the ear clip handle solid is formed by symmetrical additive manufacturing through a 180° rotation. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, a plane is created using the Plane function, and a sketch is created within the plane using the Sketch function to draw the ear hole base contour. The Extrude function is used to additively manufacture a single ear part. After drawing the ear hole circular contour in the same plane, the Extrude function is used to subtract material to obtain the drilled single ear part. Finally, the Pattern function is used to copy and additively manufacture the final product, as shown below. Figure 8 The image shows the physical entity of the ear clip handle on both sides.

[0141] Furthermore, the peaks and troughs of the ear clip teeth are rounded. The peaks are rounded with a radius of 0.55 mm, and the troughs are rounded with a radius of 0.35 mm. That is, the ear clip teeth are obtained by using the FBlend function in the DeisgnModeler module of the finite element software Ansys Workbench.

[0142] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again.

[0143] Example 4:

[0144] This embodiment discloses a finite element modeling method for the housing and rear accessories of an aviation electrical connector. Based on Embodiment 1, it further optimizes the modeling of the outer nut:

[0145] The outer nut model is divided into an internal thread entity, a nut base entity, and an internal boss entity. A circumferential division parameter N is set, where 180° is divisible by N. Based on the division parameter N, 2N discrete points are established at equal intervals on the circumferential contour of the internal thread. The discrete distance between each discrete point and the center of the circumferential contour is calculated. Based on this distance, the polar coordinates of the corresponding discrete point relative to the center of the circumferential contour are calculated. Within the circumferential range of 0-180°, the discrete points are sequentially connected to form a half-contour of the internal thread. Then, the half-contour is copied axially symmetrically to obtain the circumferential contour of the internal thread after equal-length segmentation. An axial division parameter M is set, where the pitch of the nut's internal thread entity is divisible by M, and 2N is divisible by M. Along the axial direction of the nut's internal thread entity, every... The distance / M is used to divide the internal thread of the nut into discrete layers. This indicates the pitch of the internal thread of the nut; here, N=24 and M=16.

[0146] The formula for calculating the discrete distance of the internal thread is as follows:

[0147] ;

[0148] Where: r represents the discrete distance of the internal thread between the discrete point of the internal thread and the center of the circumferential profile of the internal thread; Indicates the major diameter of the nut's internal thread; Indicates the reference thread height of the nut's internal thread; Indicates the adjustment parameter; Indicates the pitch of the internal thread of the nut; This represents the angle between the line connecting the discrete point of the internal thread and the center of the circumferential profile of the internal thread and the positive direction of the horizontal axis. Indicates the first angle threshold; Indicates the second angle threshold; This represents the difference between the major diameter of the nut's internal thread and twice the working height of the internal thread. An adjustment increment is added to the discrete distance of the internal thread, wherein the adjustment increment is less than or equal to 0.12 mm.

[0149] The horizontal interface between the first and second pitches is extracted from the external thread of the housing. A circumferential profile of the internal thread is established on this horizontal interface. Based on the aforementioned formula for calculating the discrete distance of the internal thread, the nut's internal thread profile is discretized into circumferentially equal-length segments, transforming the curved profile into multiple connected straight segments. A circle with a diameter of 12mm is drawn on a reference plane. Using this as a geometric reference, a cylinder with a single pitch height is obtained through additive manufacturing via extrusion. Axially, starting from the first internal thread circumferential profile, subtractive manufacturing is performed through profile connection to form a shape as shown... Figure 9 The solid internal thread of the single-pitch nut shown.

[0150] In the DesignModeler module of the finite element software Ansys Workbench, a reference plane is established using the Plane function. Two sketches are then created on this plane using the Sketch function to draw the circumferential profile of the internal thread and the reference circle profile. Using the Plane function, several planes perpendicular to the axis are created, translated, and rotated. On each of these planes, a sketch is created using the Sketch function to draw the circumferential profile of the internal thread. The Extrude function is used for additive manufacturing, obtaining a single-pitch height cylinder based on the reference circle profile. Finally, the Skin function is used for subtraction, obtaining a single-pitch nut internal thread solid based on the circumferential profiles of the internal threads on each plane.

[0151] Using the solid internal thread of a single-pitch nut as the geometric datum, the solid internal thread of the nut is obtained through axial replication. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, the Pattern function is used to replicate the additive manufacturing process to obtain the solid internal thread. Figure 10 The nut with internal thread shown.

[0152] At one end of the nut's internal thread, perpendicular to the axial direction, a set of concentric circles with diameters of 11.5 mm and 12.7 mm are drawn as geometric references. The nut base cylinder is then obtained through additive manufacturing using an extrusion method, with a height of 6.43 mm. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, a plane is created using the Plane function, and a sketch is created on the plane using the Sketch function to draw the concentric circle outline. The nut base cylinder is then obtained through additive manufacturing using the Extrude function.

[0153] On a plane perpendicular to the axial direction and 1.93 mm away from the solid surface of the nut's internal thread, a set of concentric circles with diameters of 10.7 mm and 11.5 mm were drawn as geometric references. Through extrusion additive manufacturing, the first-level step of the inner boss portion was obtained, with a height of 3.4 mm. On a plane perpendicular to the axial direction and 2.5 mm away from the end face of the first-level step, a set of concentric circles with diameters of 10 mm and 10.7 mm were drawn as geometric references. Through extrusion additive manufacturing, the second-level step was obtained, with a height of 0.9 mm, forming the solid inner boss of the nut. Specifically, in the DesignModeler module of the finite element software Ansys Workbench, a plane was created using the Plane function. A sketch was then created on the plane using the Sketch function, and the concentric circle outline was drawn. The first-level step of the inner boss was obtained using the Extrude function. Repeating the Plane, Sketch, and Extrude functions resulted in the second-level step of the inner boss, ultimately forming the solid inner boss portion. Figure 11 The solid inner boss of the nut shown.

[0154] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again.

[0155] Example 4:

[0156] This embodiment discloses a finite element modeling method for the housing and rear accessories of an aviation electrical connector. Based on Embodiment 1, it further optimizes the method by setting the material of the housing model, ear clip model, and outer nut model to A6061T6, with the following mechanical property parameters: Young's modulus 71000 MPa, Poisson's ratio 0.33, yield strength 280 MPa, hardening modulus 523 MPa, and ultimate tensile strength 320 MPa. The material parameters are set using the Bilinear Isotropic Hardening entry in the Engineering Data submodule of the Static Structural module in the finite element software Ansys Workbench.

[0157] The contact pairs include surface-to-surface contacts between the shell model and the ear clip model, the shell model and the outer nut model, and the ear clip model and the outer nut model. The friction coefficient between all three contact pairs is set to 0.15, with no initial gap. In the Static Structural module of the finite element software Ansys Workbench, the surface-to-surface contacts are set using the Connections function of the Model submodule, and the friction coefficient and initial gap are set using the Contacts subfunction of the Connections function.

[0158] The mesh was generated using tetrahedral elements, with a finer mesh at the threaded areas. In the Static Structural module of the finite element software AnsysWorkbench, the Mesh function of the Setup submodule was used for automatic mesh generation, resulting in a tetrahedral element mesh with 163,880 elements. The initial contact and post-meshing geometric effects are shown below. Figure 12 As shown.

[0159] Fixed constraints are set on the square plate end face and base end face of the shell model, as well as the ear hole of the ear clip model. A clockwise rotation angle of 10° is set on the outer surface of the inner boss of the outer nut model, and the load is applied in 10 steps. That is, in the Static Structural module of the finite element software Ansys Workbench, the Supports function of the Setup submodule is used to add Fixed Support to the square plate end face, base end face of the shell model, and ear hole of the ear clip model to achieve their fixed constraints. The Supports function is also used to add Remote Displacement to the outer surface of the inner boss of the outer nut model to achieve rotational displacement expressed in angles.

[0160] Numerical calculations were performed based on the given finite element model of the aviation electrical connector housing and accessories to obtain the maximum stress value and location of the structure during the tightening of the outer nut. The variation of the maximum stress with the tightening torque and the location of the maximum stress are shown below. Figure 13 and Figure 14 As shown. By Figure 13 It can be seen that when the tightening torque reaches 8.8 Nm, the maximum stress reaches the material's ultimate strength of 320 MPa. Figure 14 It can be seen that the maximum stress is located near the root of the tooth at 90° clockwise on the first external thread.

[0161] The validity of the numerical calculation results obtained by the finite element modeling method for an aviation electrical connector housing and rear accessory proposed in this invention was verified through a series of tightening tests. The objects of the tightening tests and the finite element model objects were the same type of aviation electrical connector housing and rear accessory. After two repeated destructive tightening tests, the critical tightening torques that caused strength failure of the external thread were found to be between 7.8 Nm and 9.4 Nm and between 8.4 Nm and 10.1 Nm, respectively, both showing good agreement with the calculated value of 8.8 Nm. Enlarged optical images of the samples that underwent strength failure are shown below. Figure 15 As shown, its location is in good agreement with the location of the maximum stress obtained by numerical calculation based on the finite element model.

[0162] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again.

[0163] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A finite element modeling method for aviation electrical connectors, characterized in that, Includes the following steps: Step 1: Decompose the aviation electrical connector into a housing model, an ear clip model, and an outer nut model, and perform solid disassembly of the structure of the housing model, ear clip model, and outer nut model; Step 2: Based on the entity splitting results, establish the shell model; Step 3: Based on the solid features on the shell model that mate with the ear clip model, establish the ear clip model; Step 4: Based on the solid features of the shell model and the outer nut model that mate, and based on the solid features of the ear clip model that mate with the outer nut model, establish the outer nut model; Step 5: Set the material parameters and contact parameters for the shell model, ear clip model, and outer nut model; Step 6: Mesh the shell model, ear clip model, and outer nut model, and set boundary conditions; Step 3 specifically includes: Step 3.1: Disassemble the ear clip model into the ear clip teeth solid, the ear clip base solid, and the ear clip handle solid; Step 3.2: Extract the tooth profile of the shell tooth entity, and obtain the ear clip tooth entity that meshes with the shell tooth entity and faces the opposite direction by filling additive manufacturing; Step 3.3: Build an ear clip base entity by stretching at the end of the ear clip tooth entity away from the shell model, and build an ear clip groove entity on the ear clip base entity; Step 3.4: Build ear clip handle entities symmetrically on both sides of the end of the ear clip base entity that is away from the shell model.

2. The finite element modeling method for aviation electrical connectors according to claim 1, characterized in that, Step 2 specifically includes: Step 2.1: Decompose the shell model into the shell external thread entity, the shell base entity, and the shell gear entity; Step 2.2: Discretize the circumferential profile of the external thread of the shell external thread entity by circumferential equal-length segmentation to convert the circumferential profile of the external thread into several straight segments connected in sequence; Discretize the external thread entity of the shell external thread entity by axial equal-length segmentation to obtain several discrete layers. Step 2.3: Based on the straight line segments, additive and subtractive modeling is used to obtain the single-pitch shell external thread entity. The single-pitch shell external thread entity is then copied axially to obtain the entire shell external thread entity. Step 2.4: Obtain the shell base solid by stretching additive manufacturing at one end of the external threaded solid of the shell; Step 2.5: Create a circumferential profile of the meshing tooth at the other end of the external thread entity of the shell, and create a single meshing tooth of the shell on the circumferential profile of the meshing tooth. Copy the single meshing tooth of the shell at equal intervals along the circumferential profile of the meshing tooth to obtain the entire meshing tooth entity of the shell.

3. The finite element modeling method for aviation electrical connectors according to claim 2, characterized in that, Step 2.2 specifically includes: Step 2.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points on the circumferential profile of the external thread at equal intervals; Step 2.2.2: Calculate the discrete distance between each discrete point of the external thread and the center of the circumferential profile of the external thread; Step 2.2.3: Based on the discrete distance of the external thread, calculate the polar coordinates of the corresponding discrete point of the external thread relative to the center of the circumferential profile of the external thread. Connect the discrete points of the external thread sequentially within the circumferential range of 0-180° to form a half profile of the external thread. Then, copy the half profile of the external thread symmetrically to obtain the circumferential profile of the external thread after circumferential equal-length segmented discretization. Step 2.2.4: Set the axial division parameter M so that the pitch of the external thread of the housing can be divided by M, and 2N can be divided by M. Step 2.2.5: Along the axial direction of the external threaded body of the housing, every P... W The distance / M divides the external threaded solid of the shell into discrete layers, P W This indicates the pitch of the external threaded entity of the housing.

4. The finite element modeling method for aviation electrical connectors according to claim 3, characterized in that, The formula for calculating the discrete distance of the external thread is as follows: ； Where: R represents the discrete distance of the external thread between the discrete point of the external thread and the center of the circumferential profile of the external thread; d W Indicates the major diameter of the external thread of the housing; H W Indicates the reference thread height of the external thread of the housing; ρ W P represents the diameter of the root circle of the external thread on the housing; W Indicates the pitch of the external thread on the housing; This represents the angle between the line connecting the discrete point of the external thread and the center of the circumferential profile of the external thread and the positive direction of the horizontal axis. The first angle threshold representing the discrete points of the external thread; The second angle threshold represents the discrete points of the external thread.

5. The finite element modeling method for aviation electrical connectors according to claim 1, characterized in that, Step 3.2 specifically includes: Step 3.2.1: Extract any two adjacent single-shell teeth from the shell tooth entity, and extract the peaks and troughs of the region between the two single-shell teeth; Step 3.2.2: In the space between the crest and trough, based on the tooth profile of the shell tooth entity, a single ear clip tooth that meshes with the shell tooth entity and faces the opposite direction is obtained by filling additive manufacturing. Step 3.2.3: Copy the single tooth of the ear clip along the circumferential direction to obtain the entire ear clip tooth entity.

6. The finite element modeling method for aviation electrical connectors according to claim 5, characterized in that, Step 4 specifically includes: Step 4.1: Disassemble the outer nut model into the nut internal thread solid, the nut base solid, and the nut internal boss solid; Step 4.2: Extract the horizontal interface between the first pitch and the second pitch on the external thread entity of the shell, establish the circumferential profile of the internal thread on the horizontal interface, and perform circumferential equal-length segment discretization on the internal thread circumferential profile to convert the internal thread circumferential profile into several straight segments connected in sequence; perform axial equal-length segment discretization on the internal thread entity of the nut to obtain several discrete layers. Step 4.3: Based on the straight line segments, use the contour connection method to add and subtract materials to obtain the single-pitch nut internal thread entity. Axially copy the single-pitch nut internal thread entity to obtain the entire nut internal thread entity. Step 4.4: Build a nut base cylinder entity at one end of the nut's internal thread entity; Step 4.5: Create the inner boss entity of the nut based on the contour of the ear clip groove entity inside the nut base cylinder entity.

7. The finite element modeling method for aviation electrical connectors according to claim 6, characterized in that, Step 4.2 specifically includes: Step 4.2.1: Set the circumferential division parameter N, where 180° is divisible by N; based on the division parameter N, establish 2N discrete points of the internal thread at equal intervals on the circumferential profile of the internal thread; Step 4.2.2: Calculate the discrete distance between each discrete point of the internal thread and the center of the circumferential profile of the internal thread; Step 4.2.3: Based on the internal thread discrete distance, calculate the polar coordinates of the corresponding internal thread discrete point relative to the center of the internal thread circumferential profile. Connect the internal thread discrete points sequentially within the circumferential range of 0-180° to form an internal thread half profile. Then, axially symmetrically copy the internal thread half profile to obtain the internal thread circumferential profile after circumferential equal-length segmented discreteness. Step 4.2.4: Set the axial division parameter M so that the pitch of the internal thread of the nut can be divided by M, and 2N can be divided by M. Step 4.2.5: Along the axial direction of the nut's internal thread, every P... n The distance / M divides the internal thread of the nut into discrete layers, P n This indicates the pitch of the internal thread of the nut.

8. The finite element modeling method for aviation electrical connectors according to claim 7, characterized in that, The formula for calculating the discrete distance of the internal thread is as follows: ； Where: r represents the discrete distance of the internal thread between the discrete point of the internal thread and the center of the circumferential profile of the internal thread; d n Indicates the major diameter of the nut's internal thread; H n Indicates the reference thread height of the nut's internal thread; ρ n Indicates the adjustment parameter; P n Indicates the pitch of the internal thread of the nut; This represents the angle between the line connecting the discrete point of the internal thread and the center of the circumferential profile of the internal thread and the positive direction of the horizontal axis. The first angle threshold representing the discrete points of the internal thread; The second angle threshold represents the discrete point of the internal thread; d1 represents the difference between the major diameter of the nut's internal thread and twice the working height of the internal thread.

9. The finite element modeling method for aviation electrical connectors according to claim 8, characterized in that, The incremental distance for the discrete distance of the internal thread is increased by adjusting the distance.

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