阅读说明：本技术 一种鱼眼端子及电路板模组 (Fisheye terminal and circuit board module ) 是由 刘寅 俞斌 张瑞 尹淼晶 高晓刚 于 2021-07-21 设计创作，主要内容包括：本申请实施例涉及电气连接技术领域,特别涉及一种鱼眼端子,顺应结构包括沿第二方向依次设置的两个连接体,两个连接体均包括沿第一方向依次设置的第一延伸体以及第二延伸体,其中,两个第一延伸体设有朝向相互远离的方向凸伸的第一凸起,两个第二延伸体设有朝向相互远离的方向凸伸的第二凸起,第一方向与第二方向垂直。本申请实施例还提供一种电路板模组。本申请实施例提供的鱼眼端子及电路板模组,在将鱼眼端子插入电路板的过孔之后,可减小鱼眼端子与过孔的孔壁的接触电阻。(The embodiment of the application relates to the technical field of electrical connection, in particular to fisheye terminal, compliance structure includes two connectors that set gradually along the second direction, and two connectors all include the first extension and the second extension that set gradually along the first direction, and wherein, two first extensions are equipped with the protruding first arch of stretching of the direction that keeps away from each other of orientation, and two second extensions are equipped with the protruding second arch of stretching of the direction that keeps away from each other of orientation, and first direction is perpendicular with the second direction. The embodiment of the application also provides a circuit board module. The fisheye terminal and the circuit board module provided by the embodiment of the application can reduce the contact resistance of the fisheye terminal and the hole wall of the through hole after the fisheye terminal is inserted into the through hole of the circuit board.)

1. A fisheye terminal for insertion into a via of a circuit board in a first direction, comprising:

the shoulder structure, the compliant structure and the lead-in structure are sequentially arranged along the first direction;

the compliant structure comprises two connecting bodies which are sequentially arranged along a second direction, the two connecting bodies are connected with the shoulder structure and the leading-in structure, the two connecting bodies comprise a first extending body and a second extending body which are sequentially arranged along a first direction, the two first extending bodies are provided with first bulges which protrude towards directions far away from each other, the two second extending bodies are provided with second bulges which protrude towards directions far away from each other, and the first direction is perpendicular to the second direction;

after the fisheye terminal is inserted into the via hole, the two first bulges are pressed and held by the wall of the via hole to reduce the maximum size of the fisheye terminal in the first direction, which is perpendicular to the first direction, of the two first bulges, and the two second bulges are pressed and held by the wall of the via hole to reduce the maximum size of the fisheye terminal in the first direction, which is perpendicular to the second direction, of the two second bulges.

2. The fisheye terminal of claim 1 wherein any of the first extensions has a first recess recessed toward the first protrusion on a side of and facing the first protrusion facing away from the first extension.

3. The fisheye terminal of claim 1 wherein any of the second extensions has a second recess recessed toward the second protrusion on a side of and facing the second protrusion facing away from the second extension.

4. The fisheye terminal of claim 1 wherein the direction of protrusion of one of the two first protrusions is a third direction and the direction of protrusion of one of the two second protrusions is a fourth direction, one of the third and fourth directions being perpendicular to the first and second directions, respectively.

5. The fisheye terminal of claim 4 wherein the third direction is the same as or opposite the fourth direction.

6. The fisheye terminal of any of claims 1-5 wherein each of the two connectors includes a third extension, the third extension of any of the connectors is connected to the first extension and the second extension of that connector, and the first extension, the second extension and the third extension of any of the connectors are disposed in sequence along the first direction.

7. The fisheye terminal of claim 6 wherein two of the third extensions are disposed in series along the second direction.

8. The fisheye terminal of any of claims 1-5 wherein the lead-in structure has a first end and a second end in sequence along the first direction, the first end being connected to the two second extensions and the second end having a lead-in angle.

9. The fisheye terminal of any of claims 1-5 wherein the shoulder structure is connected to both of the first extensions.

10. A circuit board module, comprising: a circuit board and the fisheye terminal of any of claims 1-9;

the circuit board is provided with a via hole;

the fisheye terminal is through the via hole runs through the circuit board, the shoulder structure is located one side of circuit board, two first arch is in the pressure of via hole pore wall is held, is reduced the fisheye terminal is located two first arch is in the perpendicular to the jumbo size on the first direction, two the second arch is in the pressure of via hole pore wall is held, is reduced the fisheye terminal is located two the second arch is in the perpendicular to the jumbo size on the first direction, leading-in structure is located the opposite side of circuit board.

Technical Field

The embodiment of the application relates to the technical field of electrical connection, in particular to a fisheye terminal and a circuit board module.

Background

At present, connection methods for connecting signals between an electronic device and a circuit board are classified into a soldered connection and a solderless connection. In solderless connection, the fisheye terminal has the characteristics of small insertion force, short process, vibration resistance, tolerance compensation, small damage to a through hole of a printed circuit board and the like, so that the fisheye terminal is more and more widely applied.

The existing fisheye terminal comprises a shoulder structure, two elastic parts connected with the shoulder structure and a leading-in structure connected with the two elastic parts, wherein the elastic parts are in an arc line shape, the two elastic parts are oppositely arranged, and a fisheye hole is formed between the two elastic parts. After the fisheye terminal is inserted into the through hole, the two elastic parts of the fisheye terminal are attached to the hole wall of the through hole and elastically deform under the extrusion of the hole wall of the through hole, so that the fisheye terminal is electrically connected with the circuit board.

The inventor finds that, after the existing fisheye terminal is inserted into the via hole, only two elastic parts are in contact with the hole wall of the via hole, and the two elastic parts and the hole wall of the via hole are in a contact form of a "single-peak contact pressure area", so that the contact area between the fisheye terminal and the hole wall of the via hole is small, and the contact resistance between the fisheye terminal and the hole wall of the via hole is large.

Therefore, it is desirable to provide a fisheye terminal and a circuit board module, which can reduce the contact resistance between the fisheye terminal and the wall of the via hole after the fisheye terminal is inserted into the via hole of the circuit board.

Disclosure of Invention

An object of the embodiment of the application is to provide a fisheye terminal and circuit board module, after inserting the fisheye terminal in the via hole of circuit board, reduce the contact resistance of fisheye terminal and the pore wall of via hole.

In order to solve the above problem, an embodiment of the present application provides a fisheye terminal for being inserted into a via hole of a circuit board along a first direction, including: the shoulder structure, the compliant structure and the lead-in structure are sequentially arranged along the first direction; the compliant structure comprises two connecting bodies which are sequentially arranged along a second direction, the two connecting bodies are connected with the shoulder structure and the leading-in structure, the two connecting bodies comprise a first extending body and a second extending body which are sequentially arranged along a first direction, the two first extending bodies are provided with first bulges which protrude towards directions far away from each other, the two second extending bodies are provided with second bulges which protrude towards directions far away from each other, and the first direction is perpendicular to the second direction; after the fisheye terminal is inserted into the via hole, the two first bulges are pressed and held by the wall of the via hole to reduce the maximum size of the fisheye terminal in the first direction, which is perpendicular to the first direction, of the two first bulges, and the two second bulges are pressed and held by the wall of the via hole to reduce the maximum size of the fisheye terminal in the first direction, which is perpendicular to the second direction, of the two second bulges.

In addition, this application embodiment still provides a circuit board module, includes: the circuit board and the fisheye terminal; the circuit board is provided with a via hole; the fisheye terminal is through the via hole runs through the circuit board, the shoulder structure is located one side of circuit board, two first arch is in the pressure of via hole pore wall is held, is reduced the fisheye terminal is located two first arch is in the perpendicular to the jumbo size on the first direction, two the second arch is in the pressure of via hole pore wall is held, is reduced the fisheye terminal is located two the second arch is in the perpendicular to the jumbo size on the first direction, leading-in structure is located the opposite side of circuit board.

The embodiment of the application provides a fisheye terminal and circuit board module, the compliance structure includes two connectors that set gradually along the second direction, two connectors all with the shoulder structure and leading-in structure link to each other, two connectors all include the first extension and the second extension that set gradually along the first direction, wherein, two first extensions are equipped with the first arch of protruding the stretching of the direction of keeping away from each other, two second extensions are equipped with the second arch of protruding the stretching of the direction of keeping away from each other, after the fisheye terminal inserts the via hole, two first arch is under the pressure of via hole pore wall, dwindles the fisheye terminal is located two first arch is in perpendicular to the maximum size on the first direction, and two second arch is under the pressure of via hole pore wall, dwindles the fisheye terminal is located two second arch is in perpendicular to the maximum size on the first direction, so, the fisheye terminal that this application embodiment provided has two first archs and two second archs and the laminating of via hole pore wall after the via hole of inserting the circuit board to increased the area of contact of fisheye terminal and the pore wall of via hole, and then reduced the contact resistance between fisheye terminal and the via hole pore wall.

In addition, any one first extending body is provided with a first groove which is concave towards the first protrusion on one side of the first protrusion, which is far away from the first extending body, and at the position opposite to the first protrusion. So, after inserting the fisheye terminal through-hole, can be so that the fisheye terminal is located two first protruding department is changeed and is taken place deformation under the extrusion of the pore wall of through-hole to further increase the area of contact of two first protruding departments and the through-hole pore wall of fisheye terminal.

In addition, any one of the second extending bodies is provided with a second groove which is concave towards the second protrusion on one side of the second protrusion, which is far away from the second extending body, and is opposite to the second protrusion. So, after inserting the fisheye terminal through-hole, can be so that the fisheye terminal is located two the protruding department of second is changeed and is taken place deformation under the extrusion of the pore wall of through-hole to further increase the area of contact of two protruding departments of second and through-hole pore wall of fisheye terminal.

In addition, the protruding direction of one of the two first protrusions is a third direction, the protruding direction of one of the two second protrusions is a fourth direction, and one of the third direction and the fourth direction is perpendicular to the first direction and the second direction respectively.

In addition, the third direction is the same as or opposite to the fourth direction.

In addition, the two connectors each include a third extension body, the third extension body of any one of the connectors is connected to the first extension body and the second extension body of the connector, and the first extension body, the second extension body, and the third extension body of any one of the connectors are sequentially arranged along the first direction.

In addition, the two third extending bodies are sequentially arranged along the second direction.

In addition, the leading-in structure is followed first direction is equipped with first end and second end in proper order, first end with two second extension link to each other, the second end is equipped with the angle of introduction. So, at the in-process of inserting the fisheye terminal into the via hole, can make the fisheye terminal be changeed and aim at the via hole to in inserting the fisheye terminal into the via hole.

In addition, the shoulder structure is connected with the two first extending bodies.

Drawings

Fig. 1 is a schematic structural diagram of a fisheye terminal according to a first embodiment of the present disclosure;

fig. 2 is another schematic structural diagram of a fisheye terminal according to an embodiment of the disclosure;

fig. 3 is a schematic structural diagram of a fisheye terminal according to a first embodiment of the present application.

Detailed Description

The embodiment of the application provides a fisheye terminal, the compliance structure includes two connectors that set gradually along the second direction, two connectors all with shoulder structure and leading-in structure link to each other, two connectors all include first extension and the second extension that sets gradually along the first direction, wherein, two first extension is equipped with the first arch of protruding direction of keeping away from each other, two second extension is equipped with the second arch of protruding direction of keeping away from each other, after the fisheye terminal inserts the via hole, two first arch is under the pressure of via hole pore wall, dwindles the fisheye terminal is located two first arch is in the perpendicular to the maximum size in the first direction, and two second arch is under the pressure of via hole pore wall, dwindles the fisheye terminal is located two the second arch is in the perpendicular to the maximum size in the first direction, so, the fisheye terminal that this application embodiment provided has two first archs and two second archs and the laminating of via hole pore wall after the via hole of inserting the circuit board to increased the area of contact of fisheye terminal and the pore wall of via hole, and then reduced the contact resistance between fisheye terminal and the via hole pore wall.

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following describes each embodiment of the present application in detail with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in various embodiments of the present application in order to provide a better understanding of the present application. However, the technical means claimed in the present application can be realized by various changes and modifications of the following embodiments.

Referring to fig. 1, a fisheye terminal according to a first embodiment of the present application is configured to be inserted into a via hole of a circuit board (not shown) along a first direction (X direction shown in fig. 1), and includes: shoulder structure 110, compliant structure 120, and lead-in structure 130 arranged in sequence along a first direction; the compliant structure 120 includes two connecting bodies 121 sequentially arranged along a second direction (Y direction shown in fig. 1), and both of the connecting bodies 121 are connected to the shoulder structure 110 and the lead-in structure 130; with continuing reference to fig. 1 and with reference to fig. 2 and 3, each of the two connecting bodies 121 includes a first extending body 122 and a second extending body 123 sequentially arranged along a first direction, wherein the two first extending bodies 122 are provided with first protrusions 124 protruding toward directions away from each other, the two second extending bodies 123 are provided with second protrusions 125 protruding toward directions away from each other, and the first direction is perpendicular to the second direction; after the fisheye terminal is inserted into the via hole, the two first protrusions 124 are pressed against the wall of the via hole, and the two first protrusions 124 reduce the maximum dimension of the fisheye terminal in the first direction, and the two second protrusions 125 are pressed against the wall of the via hole, and the two second protrusions 125 reduce the maximum dimension of the fisheye terminal in the second direction. In the figure, the structures of the fisheye terminal are divided by broken lines, and the broken lines are not used to identify the structure of the fisheye terminal surface.

Specifically, the maximum size of the fisheye terminal in the two first protrusions 124 in the direction perpendicular to the first direction is the first size W1, the maximum size of the fisheye terminal in the two second protrusions 125 in the direction perpendicular to the first direction is the second size W2, both the first size W1 and the second size W2 are larger than the diameter of the via hole into which the fisheye terminal needs to be inserted, so that after the fisheye terminal is inserted into the via hole, since the first size W1 is larger than the diameter of the via hole, the two first protrusions 124 are pressed by the wall of the via hole to reduce the first size W1, and since the second size W2 is larger than the diameter of the via hole, the two second protrusions 125 are pressed by the wall of the via hole to reduce the second size W2, and the two first protrusions 124 and the two second protrusions 125 can be attached to the wall of the via hole; compared with the existing fisheye terminal which is only provided with two elastic parts and is attached to the wall of the via hole after the via hole of the circuit board is inserted, the fisheye terminal provided by the embodiment is provided with two first protrusions 124 and two second protrusions 125 which are attached to the wall of the via hole after the via hole is inserted, so that the contact area between the fisheye terminal and the wall of the via hole is increased, and the contact resistance between the fisheye terminal and the wall of the via hole is reduced.

More specifically, in the present embodiment, the maximum size of the fisheye terminal in the two first protrusions 124 in the direction perpendicular to the first direction is equal to the maximum size of the fisheye terminal in the two second protrusions 125 in the direction perpendicular to the first direction, that is, the first size W1 is equal to the second size W2.

In addition, compared with a fisheye terminal with only two elastic parts, the fisheye terminal provided by the embodiment increases the contact area between the fisheye terminal and the wall of the via hole after the fisheye terminal is inserted into the via hole, so that the fisheye terminal provided by the embodiment of the application can also increase the anti-vibration performance of the fisheye terminal and the connection stability of the fisheye terminal and the circuit board after the fisheye terminal provided by the embodiment of the application is inserted into the via hole compared with a fisheye terminal with only two elastic parts.

Further, any first extension body 122 has a first groove 126 recessed toward the first protrusion 124 at a position facing away from the first protrusion 124 of the first extension body 122 and facing the first protrusion 124. Therefore, the size of the first extending body 122 located in the third direction of the first protrusion 124 can be reduced, so that after the fisheye terminal is inserted into the via hole, the fisheye terminal can be easily deformed by being extruded on the via hole wall by the two first protrusions 124, the contact area between the two first protrusions 124 and the via hole wall is increased, and the contact area between the two first protrusions 124 of the fisheye terminal and the via hole wall is further increased.

Further, any one of the second extending bodies 123 has a second groove 127 recessed toward the second protrusion 125 at a position facing away from the second protrusion 125 of the second extending body 123 and facing the second protrusion 125. Therefore, the size of the second extending body 123 in the fourth direction at the second protrusion 125 can be reduced, so that after the fisheye terminal is inserted into the via hole, the fisheye terminal can be easily deformed by being extruded on the via hole wall at the two second protrusions 125, the contact area between the two second protrusions 125 and the via hole wall is increased, and the contact area between the two second protrusions 125 of the fisheye terminal and the via hole wall is further increased.

Further, the protruding direction of one of the two first protrusions 124 is a third direction (Z direction shown in fig. 2), the protruding direction of one of the two second protrusions 125 is a fourth direction, and one of the third direction and the fourth direction is perpendicular to the first direction and the second direction, respectively. In this way, when manufacturing the fisheye terminal, the two first protrusions 124 or the two second protrusions 125 can be directly formed only by punching the plate material in the third direction. Preferably, the third direction is the same as or opposite to the fourth direction. In this way, when manufacturing the fisheye terminal, the two first protrusions 124 and the two second protrusions 125 can be directly formed by only punching the plate material in the third direction, thereby reducing the manufacturing steps when manufacturing the fisheye terminal.

In this embodiment, one of the third direction and the fourth direction is perpendicular to the first direction and the second direction, respectively, and the third direction is the same as the fourth direction, that is, the other of the third direction and the fourth direction is also perpendicular to the first direction and the second direction, respectively; in an embodiment, one of the third direction and the fourth direction is perpendicular to the first direction and the second direction, respectively, and the third direction is opposite to the fourth direction, and the other of the third direction and the fourth direction is perpendicular to the first direction and the second direction, respectively.

In other changeable embodiments, one of the third direction and the fourth direction may not be perpendicular to the first direction and the second direction, respectively, or the third direction may not be the same as or opposite to the fourth direction; for example, in one example, one of the third direction and the fourth direction is the same as the second direction or opposite to the second direction, and the other of the third direction and the fourth direction is perpendicular to the first direction and the second direction, respectively; in another example, the third direction is the same or opposite to the second direction, and the fourth direction is the same or opposite to the second direction.

Further, each of the two connection bodies 121 includes a third extension 128, the third extension 128 of any connection body 121 is connected to the first extension 122 and the second extension 123 of the connection body 121, and the first extension 122, the second extension 123 and the third extension 128 of any connection body 121 are sequentially arranged along the first direction.

In the process of inserting the fisheye terminal into the via hole, when the two first protrusions 124 and the two second protrusions 125 are pressed by the hole wall of the via hole to deform the two first extending bodies 122 and the two second extending bodies 123, because the third extending body 128 of any connecting body 121 is connected to the first extending body 122 and the second extending body 123 of the connecting body 121, when the third extending body 128 elastically deforms the first extending body 122 and the second extending body 123 connected thereto, the third extending body 128 also deforms therewith, so as to reduce the deformation generated by the first extending body 122 and the second extending body 123, and further avoid that the first extending body 122 and the second extending body 123 deform excessively to cause the plastic deformation of the first extending body 122 and the second extending body 123, so that the fisheye terminal can be used continuously after being pulled out from the via hole, the number of times of using the fisheye terminal is increased. Further, two third extending bodies 128 are sequentially disposed along the second direction.

Preferably, in the present embodiment, the introduction structure 130 is provided with a first end 131 and a second end 132 in sequence along the first direction, the first end 131 is connected to the two second extensions 123, and the second end 132 is provided with the introduction angle α 1. So, at the in-process of inserting the fisheye terminal into the via hole, can make the fisheye terminal be changeed and aim at the via hole to in inserting the fisheye terminal into the via hole.

Further, the lead-in angle α 1 is between 10 degrees and 40 degrees. In the present embodiment, the angle of the introduction angle α 1 is 25 degrees; in one embodiment, the angle of the lead-in angle is 35 degrees. Further, one side that first end 131 was kept away from to second end 132 still is equipped with the fillet, so, when inserting the in-process of via hole with the fisheye terminal, when the hole wall emergence of one side and via hole that first end 131 was kept away from to second end 132 collided with, can avoid one side that first end 131 was kept away from to second end 132 to cause the damage to the hole wall that causes the via hole.

Preferably, the shoulder structure 110 is connected to two first extensions 122. Further, the maximum dimension of the shoulder structure 110 in the direction perpendicular to the first direction is larger than the aperture of the via hole into which the fisheye terminal needs to be inserted, so that, in the process of inserting the fisheye terminal into the via hole, since the maximum dimension of the shoulder structure 110 in the direction perpendicular to the first direction is larger than the aperture of the via hole, the fisheye terminal can be prevented from passing through the via hole in the first direction.

It should be noted that, in the present embodiment, it is only exemplified that the compliant structure 120 includes two first extending bodies 122 respectively having one first protrusion 124 and two second extending bodies 123 respectively having one second protrusion 125; in other changeable embodiments, when fisheye terminal via hole length is longer, fisheye terminal still can be equipped with two extension bodies that have the third arch, so, after inserting fisheye terminal in the via hole, two first archs, two second archs and two third archs of fisheye terminal are laminated with the pore wall of via hole to further increase the area of contact of fisheye terminal and via hole pore wall, and then further reduce the contact resistance of fisheye terminal and via hole pore wall.

The second embodiment of the present application provides a circuit board module, including: a circuit board and a fisheye terminal; the circuit board is provided with a via hole; the fisheye terminal comprises a shoulder structure, a compliant structure and a lead-in structure which are sequentially arranged along a first direction; the compliance structure comprises two connectors which are sequentially arranged along a second direction, the two connectors are connected with the shoulder structure and the leading-in structure, the two connectors comprise a first extending body and a second extending body which are sequentially arranged along the first direction, the two first extending bodies are provided with first bulges which protrude towards the directions away from each other, the two second extending bodies are provided with second bulges which protrude towards the directions away from each other, and the first direction is vertical to the second direction; after the fisheye terminal is inserted into the via hole, the two first bulges are pressed and held by the wall of the via hole, the maximum size of the fisheye terminal in the first direction perpendicular to the two first bulges is reduced, the two second bulges are pressed and held by the wall of the via hole, and the maximum size of the fisheye terminal in the first direction perpendicular to the two second bulges is reduced.

The fisheye terminal penetrates through the circuit board through the via hole, the shoulder structure is located on one side of the circuit board, the two first bulges are pressed and held on the wall of the via hole, the maximum size of the fisheye terminal, which is located on the two first bulges and perpendicular to the first direction, is reduced, the two second bulges are pressed and held on the wall of the via hole, the maximum size of the fisheye terminal, which is located on the two second bulges and perpendicular to the first direction, is reduced, and the lead-in structure is located on the other side of the circuit board.

In fact, the fisheye terminal included in the circuit board module provided by the second embodiment of the present application is the same as the fisheye terminal provided by the first embodiment of the present application, and therefore, the fisheye terminal included in the circuit board module provided by the second embodiment of the present application also has the same effect as the fisheye terminal provided by the first embodiment of the present application, and details are not repeated herein.

Preferably, when the board thickness of the circuit board is 1.4mm to 1.8mm (mm: mm), the diameter of the via hole is 0.8mm to 1.2mm, and then, the maximum size of the fisheye terminal located on the two first protrusions in the direction perpendicular to the first direction is 0.98mm to 1.38mm, the maximum size of the fisheye terminal located on the two second protrusions in the direction perpendicular to the first direction is 0.98mm to 1.38mm, and the distance between the two first protrusions and the two second protrusions is 1.2mm to 1.6 mm.

Specifically, the board thickness of the circuit board provided by this embodiment is 1.6mm (mm: millimeter), the diameter of the via hole is 1mm, at this time, the maximum size of the fisheye terminal located in the two first protrusions in the direction perpendicular to the first direction is 1.18mm, the maximum size of the fisheye terminal located in the two second protrusions in the direction perpendicular to the first direction is 1.18mm, and the distance between the two first protrusions and the two second protrusions is 1.4 mm.

In addition, the fisheye terminal provided by the embodiment is suitable for the circuit board with the plate thickness of 1.6mm and the diameter of the via hole of 1mm, and when the plate thickness of the circuit board or the diameter of the via hole is changed, the size of the fisheye terminal is changed accordingly. In one embodiment, the circuit board and the fisheye terminals may be modeled, and then a space between the two first bumps and the two second bumps, a maximum size of the fisheye terminals located on the two first bumps in a direction perpendicular to the first direction, and a maximum size of the fisheye terminals located on the two second bumps in a direction perpendicular to the first direction may be optimized based on a length of the via hole and an aperture of the via hole by a CAE (Computer Aided Engineering) analysis tool; specifically, when the length of the via hole is longer, the distance between the two first protrusions and the two second protrusions can be increased, and correspondingly, when the length of the via hole is shorter, the distance between the two first protrusions and the two second protrusions can be decreased; when the aperture of the via hole is large, the maximum size of the fisheye terminal in the two first protrusions in the direction perpendicular to the first direction and the maximum size of the fisheye terminal in the two second protrusions in the direction perpendicular to the first direction may be increased, and correspondingly, when the aperture of the via hole is small, the maximum size of the fisheye terminal in the two first protrusions in the direction perpendicular to the first direction and the maximum size of the fisheye terminal in the two second protrusions in the direction perpendicular to the first direction may be decreased.

In addition, the inserting force of the fisheye terminal, the deformation degree of the via hole, the contact pressure and the contact area when the fisheye terminal passes through the via hole can be analyzed through a CAE analysis tool, and the size of the first extending body and the second extending body in the third direction, the protruding length of the first protrusion, the protruding length of the second protrusion, the recessed depth of the first groove, the recessed depth of the second groove, the curvature of the surface of the first protrusion far away from the first groove and the curvature of the surface of the second protrusion far away from the second groove are optimized; specifically, when the insertion force of the fisheye terminal is large or the deformation degree of the via hole is large when the fisheye terminal is inserted into the via hole, at least one of the size of the first extension body and the second extension body in the third direction, the length of the first protrusion and the length of the second protrusion of the fisheye terminal can be reduced, and the depth of the first groove recess and the depth of the second groove recess can be increased; when the contact pressure between the fisheye terminal and the wall of the via hole is larger or the contact area is smaller, the curvature of the surface of the first protrusion far away from the first groove and the curvature of the surface of the second protrusion far away from the second groove can be reduced; when the contact pressure of the fisheye terminal and the wall of the through hole is small or the contact area is large, the curvature of the surface of the first protrusion far away from the first groove and the curvature of the surface of the second protrusion far away from the second groove can be increased.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the present application, and that various changes in form and details may be made therein without departing from the spirit and scope of the present application in practice. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the application, and it is intended that the scope of the application be limited only by the claims appended hereto.