Tool for testing hybrid integrated circuit

Abstract

The utility model provides a tool for testing a hybrid integrated circuit, and relates to the field of microelectronic integrated circuits. The tool comprises a clamp, the clamp comprises a base and a cover plate, the base and the cover plate can be combined in a covering mode to form a plurality of containing cavities, and the containing cavities are used for fixing products to be detected; the base comprises a first positioning structure, the cover plate comprises a second positioning structure, and the first positioning structure and the second positioning structure can be embedded with each other to position the base and the cover plate; a first boss and a second boss which are opposite to each other are arranged in the accommodating cavity and are used for supporting pins of a to-be-tested product. According to the tool provided by the invention, after a centrifugal detection test in one direction is completed, the direction of the to-be-detected product does not need to be changed by loading and unloading, and the direction of the clamp can be directly changed to complete a centrifugal test in the other direction. The steps of loading and unloading in a constant acceleration test are further saved, so that the working hour utilization rate is greatly improved; and meanwhile, appearance defects of products caused by clamp abrasion are reduced.

Description

Technical Field

[0001] The present disclosure relates to the fields of hybrid circuits and microelectronic integrated circuits, and particularly to a tooling for hybrid integrated circuit testing. Background Art

[0002] In the overall process of research, development, manufacturing, and application of hybrid integrated circuits (HICs), quality inspection and screening play a crucial role and are the foundation for ensuring excellent product performance and high reliability. With the booming development of the hybrid integrated circuit industry, screening technologies have continuously evolved to meet increasingly stringent quality standards. Currently, the screening system for hybrid integrated circuits covers multiple key aspects such as internal visual inspection, temperature cycling, constant acceleration, PIND detection, pre-burn-in electrical testing, aging test, three-temperature test, leak detection, and external visual inspection. Each aspect aims to detect and eliminate potential defects. Among the above-mentioned numerous screening items, the constant acceleration test, as a high-stress test, is used to test the bonding strength of the package, internal metallization, and lead system, chip, or substrate, so as to be able to eliminate parts with mechanical strength lower than the nominal value in the hybrid integrated circuit structure. The constant acceleration test, as a necessary test means, is crucial for ensuring the stability of hybrid integrated circuits in various environments.

[0003] In the prior art, since hybrid integrated circuits mostly adopt a single-sided packaging form, during the test, the products only need to be fixed in a specific fixture in a unified orientation (Y1 direction), and then placed in a centrifuge to complete the test. The process is relatively simple and direct. However, with the progress of technology and the application requirements of product miniaturization, in addition to more and more electronic components integrated on the substrate, technicians have tried to integrate electronic components on both sides of the substrate, which poses new challenges to the constant acceleration test, requiring the products to be tested in two perpendicular directions, Y1 and Y2, to comprehensively evaluate their performance in a multi-dimensional acceleration environment.

[0004] Facing this requirement, the limitations of the existing constant acceleration test fixtures are highlighted: if the old fixtures are still used, two independent loading and unloading operations need to be performed on the same product, for testing in the Y1 and Y2 directions respectively. This process is not only cumbersome and inefficient, causing unnecessary occupation and waste of equipment resources, but also increases the risk of human operation errors. Therefore, it is urgent to develop or optimize the constant acceleration test tooling to achieve fast, efficient, and accurate multi-directional testing capabilities. Summary of the Utility Model

[0005] To solve or improve the problems in the prior art, the present disclosure provides a tooling for hybrid integrated circuit testing, including a fixture. The fixture specifically includes: a base and a cover plate. The base and the cover plate can be covered and combined to form a plurality of accommodation cavities for fixing the product to be tested. A boss is arranged in the accommodation cavity for supporting the pins of the product to be tested. The base includes a first positioning structure, and the cover plate includes a second positioning structure. The first positioning structure and the second positioning structure can be engaged with each other to position the base and the cover plate.

[0006] Optionally, the base and / or the cover plate includes a groove for forming the accommodation cavity.

[0007] Optionally, the bosses in the accommodation cavity include a first boss and a second boss arranged oppositely; the first boss and the second boss have supporting surfaces parallel to each other for supporting the pins of the product to be tested.

[0008] Optionally, the base includes a plurality of grooves arranged in an array, and the aforementioned first boss is arranged at the bottom of the groove; the cover plate is provided with a plurality of second bosses corresponding to the first bosses one by one.

[0009] In the embodiment of the present disclosure, a first boss structure is introduced at the bottom of the groove to form a stepped bottom, which is specifically designed to stabilize the leads of the product to be tested. This design can hold the leads, effectively preventing the leads from tilting and bending due to centrifugal force during the test, thereby avoiding excessive pressure on the joint between the root of the lead and the glass insulator and ensuring the reliability of the insulator seal.

[0010] At the same time, the second bosses added on the cover plate correspond to the first bosses on the base. When the cover plate is closed, the second bosses penetrate into the grooves, not only stabilizing the overall product to be tested, but also particularly strengthening the support for the leads, significantly reducing the force on the leads due to centrifugal action in the constant acceleration test, reducing the risk of hidden cracks in the insulator caused by the force on the leads, and improving the safety and accuracy of the test.

[0011] Since the first boss and the second boss are respectively arranged on both sides, the fixture can still ensure the support for the leads when the installation direction is changed. Therefore, the fixture provided by the embodiment of the present disclosure can perform acceleration tests on two directions of the product to be tested without disassembling the product to be tested, and can avoid the deformation of the leads in both cases.

[0012] Optionally, the first positioning structure includes four concave structures respectively arranged at the four corners of the base, and the second positioning structure includes four convex structures respectively arranged at the four corners of the cover plate. The convex structures face the direction of covering the base and are adapted to the corresponding concave structures.

[0013] Optionally, among the first positioning structure and the second positioning structure, the size of one concave structure and the corresponding convex structure is different from that of the other three concave structures and the corresponding convex structures.

[0014] Optionally, in the first positioning structure and the second positioning structure, the concave structure and the corresponding convex structure at one end of the tooling have different dimensions from the concave structure and the corresponding convex structure at the other end of the tooling.

[0015] The present disclosure ensures that the cover plate can be accurately and tightly fitted with the base along a predetermined direction by planning the positioning structure. Moreover, concave structures with different shapes and / or different sizes are provided at the four corners of the base and / or the cover plate, effectively preventing the cover plate from being wrongly installed in the reverse direction. This not only simplifies the operation process, but also greatly improves the overall stability of the equipment and the reliability of the test results, ensuring that each test can be carried out in a safe and accurate environment.

[0016] Optionally, the groove includes one or more picking and placing grooves, which are arranged at the corresponding positions of the side wall of the groove and the corners of the shell of the product to be tested. The setting of the picking and placing grooves facilitates the picking and placing of the product to be tested, simplifies the picking and placing process of the product, and realizes fast and convenient operation.

[0017] Optionally, the base and / or the cover plate are further provided with at least one counterweight hole for adjusting the counterweight of the fixture. The counterweight hole allows the user to adjust the counterweight of the fixture according to actual needs, ensures balance during high-speed operation, effectively prevents the vibration problem of the centrifuge caused by imbalance, thus ensuring the safety of the equipment and avoiding potential accident risks. More preferably, the counterweight hole is a semi-hole, providing a flexible space for adjusting the counterweight to ensure the safety and accuracy of the test.

[0018] In the tooling provided by the embodiment of the present disclosure, a bearing base is further included; the bearing base includes a plurality of fixture bearing grooves and a through groove penetrating the bearing base; the width of the fixture bearing groove is adapted to the width of the fixture, and the depth is more than 2 / 3 of the thickness of the bearing base; the through groove is perpendicular to the fixture bearing groove.

[0019] The bearing base combines high-efficiency loading and convenient operation. It not only provides a loading function for the covered base and cover plate, but also, a plurality of fixture bearing grooves facilitate loading more products to be tested at one time, and the setting of the through groove makes it more convenient for manual picking of the fixture, improving work efficiency. The bearing base can be in a shape convenient for fixture loading. Optionally, the bearing base is rectangular; the bearing grooves on the bearing base are consistent with the external dimensions of the fixture, enabling tight assembly. In addition, in terms of material selection, the bearing base adopts a solid structure, and preferably high-hardness metal or alloy materials such as aluminum, copper, steel, etc., ensuring the durability and load-bearing capacity of the base and providing a solid support for the entire tooling system.

[0020] In the tooling provided by the embodiment of the present disclosure, a centrifuge drum is further included, and a plurality of centrifuge fixing grooves are arranged on the inner side wall of the centrifuge drum; the centrifuge fixing grooves can respectively fix the fixture in the forward or reverse direction, greatly enhancing the flexibility of the operation.

[0021] During the testing process of hybrid integrated circuits, by using the tooling provided in this disclosure in combination, it is possible to conveniently switch the acceleration test direction during a single clamping process, which not only simplifies the test process, improves test efficiency, reduces test costs, but also reduces the appearance defects of the product caused by frequent loading and unloading and fixture wear, ensuring the quality of the product to be tested. Description of the Drawings

[0022] Figure 1 It is a three-dimensional structure example diagram of the tooling provided by an embodiment of this disclosure, showing multiple jigs and a carrier base in the figure;

[0023] Figure 2 It is a three-dimensional structure example diagram of the jig in the tooling provided by an embodiment of this disclosure;

[0024] Figure 3 It is a cross-sectional view schematic diagram of the jig in the tooling provided by an embodiment of this disclosure;

[0025] Figure 4 It is a three-dimensional example diagram of the carrier base in the tooling provided by an embodiment of this disclosure;

[0026] Figure 5 It is a three-dimensional structure example diagram of the jig base in the tooling provided by an embodiment of this disclosure;

[0027] Figure 6 It is a three-dimensional structure example diagram of the jig cover plate in the tooling provided by an embodiment of this disclosure;

[0028] Figure 7 It is a schematic diagram of the jig base with a pick-and-place groove provided in the tooling of an embodiment of this disclosure;

[0029] Figure 8 It is a three-dimensional structure example diagram of the centrifuge drum included in the tooling provided by an embodiment of this disclosure.

[0030] Description of the markings in the figure:

[0031] 100: Jig;

[0032] 110: Base, 111: Concave structure, 112: Groove, 113: First boss, 114: Counterweight hole, 115: Pick-and-place groove;

[0033] 120 Cover plate, 121: Convex structure, 122: Second boss;

[0034] 130: Accommodation cavity;

[0035] 200: Carrier base;

[0036] 210: Jig carrier groove, 220: Through groove;

[0037] 300: Centrifuge drum;

[0038] 310: Centrifugal fixing groove. Specific implementation manners

[0039] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numerals in different drawings represent the same or similar elements. The following embodiments are exemplary, and the described implementation manners do not represent all implementation manners consistent with the present disclosure. The "connection" involved in the embodiments of the present disclosure mainly refers to the connection in structure, including fixed connection or detachable connection.

[0040] It should be understood that although the present disclosure uses ordinal numbers such as "first" and "second", these ordinal numbers are only used to distinguish the same type of things from each other, and do not represent their sequence, importance or quantity. Without conflict, the features in the following embodiments and implementation manners can be combined with each other.

[0041] In all stages of the research, development, production, application, etc. of hybrid integrated circuits, repeated inspections and screenings are required to ensure the quality of the products. For the constant acceleration test, under the requirement that the product to be tested needs to be tested in two perpendicular directions of Y1 and Y2, if the original constant acceleration fixture is used, the product to be tested needs to be loaded and unloaded twice respectively to complete the corresponding test, which is relatively cumbersome to operate and wastes working hours and the running time of the test equipment.

[0042] For this reason, the embodiments of the present disclosure provide a tooling for testing hybrid integrated circuits, which is used to detect and screen integrated circuits, and can complete the constant acceleration test without loading and unloading the hybrid integrated circuit product to be tested (abbreviated as the product to be tested) twice, and does not damage the leads (also known as pins or terminals) of the hybrid integrated circuit. As Figure 1-3 shown, the tooling includes a fixture 100, and the fixture 100 includes a base 110 and a cover plate 120. For example Figure 2 In the described structure, the cover plate 120 is arranged above the base 110 and covers the base 110. The base 110 and the cover plate 120 can be covered and form a plurality of accommodating cavities 130 therebetween, and the accommodating cavities 130 can accommodate and fix the product to be tested; for example Figure 3 In the longitudinal sectional view of the fixture 100 shown, the cover plate 120 and the base 110 are covered, and a plurality of accommodating cavities 130 are formed inside the fixture 100, and a plurality of products to be tested are fixed in the accommodating cavities 130 inside the fixture 100.

[0043] Optionally, the base 110 is further provided with a first positioning structure, and the cover plate 120 is provided with a second positioning structure. The first positioning structure and the second positioning structure can be engaged with each other and can position the base 110 and the cover plate 120; as Figure 2As shown in FIGS. 2 or 3, the base 110 can accurately and precisely fit tightly with the cover plate 120 in a predetermined direction, so that the shape of the accommodation cavity 130 is accurate, avoiding damage to the product under test inside the accommodation cavity 130 during the test process.

[0044] Optionally, grooves for forming the accommodation cavity 130 are provided on the base 110 and / or the cover plate 120. That is, the grooves can be provided separately on the base 110 or the cover plate 120, or grooves can be provided on both the base 110 and the cover plate 120. For example Figure 5 and Figure 6 In the embodiment shown, the groove 112 is provided separately on the base 110.

[0045] Optionally, a boss is provided in the accommodation cavity 130 to confine the leads of the product under test in a relatively small space, avoiding problems such as deformation of the leads of the product under test during the constant acceleration test. Considering that the leads (if any) of the product under test are generally arranged at the bottom of the accommodation cavity 130 (i.e., the leads face downwards) during actual testing, the boss is also correspondingly provided at the bottom of the accommodation cavity 130. The number and size of the bosses can be determined according to the actual situation of the product under test. Referring to Figure 3 、 Figure 5 and Figure 6 , a first boss 113 and a second boss 122 are provided oppositely in the accommodation cavity 130, and the first boss 113 and the second boss 122 can support the leads of the product under test. The first boss 113 and / or the second boss 122 is / are arranged at the bottom of the accommodation cavity 130; the first boss 113 and the second boss 122 have supporting surfaces parallel to each other, and the above-mentioned supporting surfaces can support the leads of the product under test. That is, as Figure 3 shown, a stepped bottom is formed at the bottom of the accommodation cavity 130 to stabilize the leads of the product under test, which can effectively prevent the leads from tilting and bending due to centrifugal force during the test, thereby avoiding excessive pressure on the joint between the root of the lead and the glass insulator and ensuring the reliability of the insulator seal.

[0046] In a specific embodiment, as Figure 3 and Figure 5 , a plurality of slots according to different product sizes are provided on the surface of the base 110 facing the cover plate 120, facilitating the placement and fixation of the product under test. A first boss 113 protruding away from the bottom of the groove 112 is provided at the bottom of the groove 112. When the product under test is placed in the groove 112, the upper surface (supporting surface) of the first boss 113 can support the leads of the product under test. Matched with it, as Figure 6As shown in the figure, on the side of the cover plate 120 facing the base 110 and closing towards it, there is a second boss 122 facing the first boss 113 and matching the shape of the first boss 113. Place the product to be tested in the base groove 112, close the cover plate 120, and the surface of the second boss 122 facing the base 110 can contact the leads of the product to be tested. During the acceleration test in another direction, it supports the pins of the product to be tested.

[0047] In an alternative embodiment, the groove and the first boss can also be provided on the side of the cover plate 120 facing the closing direction of the base, and the second boss is provided on the side of the base 110 facing the closing direction of the cover plate 120; in another alternative embodiment, grooves and first bosses are provided on the sides of both the base 110 and the cover plate 120 facing each other's closing directions. The above alternative embodiments can all be implemented according to the understanding of those skilled in the art, so they will not be elaborated herein.

[0048] In an alternative embodiment, the groove is a rectangular groove, and the corners of the rectangular groove are provided with chamfers or rounded corners. Further, correspondingly, some corners of the boss provided in the groove are provided with chamfers or rounded corners. Preferably, some corners of the boss in the accommodating cavity 130 are also provided with chamfers or rounded corners, such as Figure 5 and Figure 6 As shown in the figure, two corners of the boss are provided with chamfers. Such a design facilitates the installation and disassembly of the base 110 and the cover plate 120, and reduces the situation where the cover plate 120 and the base 110 are locked and difficult to disassemble after being stressed in the constant acceleration test.

[0049] According to the above embodiments, as Figure 5 shown in the figure, the first positioning structure includes four concave structures 111 respectively provided at the four corners of the base; the second positioning structure includes four convex structures 121 respectively provided at the four corners of the cover plate. The convex structures 121 face the closing direction of the base and are adapted to the corresponding concave structures 111 to ensure that during the acceleration test, the base 110 and the cover plate 120 can be kept closely fitted without problems such as dislocation.

[0050] In a preferred embodiment, the sizes of one concave structure and the corresponding convex structure in the first positioning structure and the second positioning structure are different from those of the other three concave structures and the corresponding convex structures. In another preferred embodiment, as Figure 5 or Figure 6 shown in the figure, the sizes of the two concave structures and the corresponding convex structures at one end of the tooling are different from those of the two concave structures and the corresponding convex structures at the other end of the tooling.

[0051] The concave and convex structures are set with different sizes for positioning purposes, so as to facilitate the operator to install the cover plate 120 on the base 110 and prevent the cover plate 120 from being installed in the wrong direction. It is understandable that those skilled in the art can also adopt other implementation manners, such as setting positioning structures with different shapes, as long as they can facilitate positioning and avoid incorrect installation. Therefore, other implementation manners will not be elaborated herein.

[0052] Further, in one embodiment, as Figure 7 shown, the groove includes one or more pick-and-place slots 115, which are arranged at corresponding positions between the side wall of the groove and the corners of the shell of the product to be tested. For example Figure 7 in the structure shown, each groove is provided with four pick-and-place slots 115, which are respectively arranged at corresponding positions between the side wall of the groove and the corners of the shell of the product to be tested, so as to facilitate the picking and placing of the product to be tested.

[0053] Further, in one embodiment, the base 110 and / or the cover plate 120 are / is further provided with at least one counterweight hole 114 for adjusting the counterweight of the fixture 100. In a specific implementation manner, as Figure 5 shown, a counterweight hole is provided on the upper surface of the base 110, which can facilitate the adjustment of the counterweight of the base 110, so as to avoid the phenomenon of unbalanced rotation of the centrifugal equipment during the acceleration test.

[0054] Further, the tooling further includes a carrier base 200, which can temporarily carry and transfer multiple fixtures 100 at one time during the hybrid integrated circuit test operation, making the operation more convenient, improving work efficiency, and avoiding the collision caused by the unstable placement of the fixture 100. In addition, placing the fixture 100 in the carrier base 200 can also prevent the product to be tested from falling due to the accidental opening of the base 110 and the cover plate 120 of the fixture 100.

[0055] In a specific implementation manner, as Figure 1 and 4 shown, the carrier base 200 is provided with a plurality of fixture receiving slots 210 and through slots 220 penetrating the carrier base; the width of the fixture receiving slot 210 is adapted to the width of the fixture 100, so that the fixture 100 can be tightly inserted into the fixture receiving slot 210, and at the same time, the fixture can also be taken out from the fixture receiving slot; the depth of the fixture receiving slot 210 is 2 / 3 or more of the thickness of the carrier base to ensure that the fixture 100 can be stably inserted into the fixture receiving slot 210 without problems such as shaking or skewing; the extending direction of the through slot 220 is perpendicular to the depth direction of the fixture receiving slot 210.

[0056] In a typical embodiment, the through slot 220 penetrates all the fixture receiving slots 210.

[0057] In a typical embodiment, the through slot 220 has the same depth as the fixture receiving slot 210.

[0058] Further, the tooling further includes a centrifugal drum 300. In a specific embodiment, as Figure 8 shown, a plurality of centrifugal fixing grooves 310 are provided on the inner side wall of the centrifugal drum 300; the centrifugal fixing grooves 310 can respectively fix the fixture 100 forward or backward. Preferably, a pick-up and placement opening is provided at the upper end of the centrifugal fixing groove 310 to facilitate the loading and unloading of the fixture 100.

[0059] Optionally, the centrifugal drum 300 is connected to a driving device such as a motor, so that the centrifugal drum 300 can rotate in different directions and at different speeds under the drive of the motor.

[0060] In a typical embodiment, the depth of the centrifugal fixing groove 310 is less than the height of the fixture 100, which facilitates the pick-up and placement of the fixture 100.

[0061] To make the features of the tooling involved in the present disclosure easier to understand, the present disclosure also exemplarily provides the operation steps for performing a centrifugal test using the above tooling:

[0062] Step 1: Place the products to be tested in the respective grooves 112 of the base 110 to be used in accordance with the specified direction;

[0063] Step 2: Cover the base 110 with the cover plate 120;

[0064] Step 3: Place each fixture 100 into the respective centrifugal fixing grooves 310 of the centrifugal drum 300, and connect the centrifugal drum 300 to a centrifuge with a pre-set program; start the centrifuge to complete a centrifugal test in one direction, such as the Y1 direction. It should be understood that the centrifuge includes a driving device capable of driving the centrifugal drum to operate, such as a motor, a hydraulic motor, a pneumatic motor, etc., and its drive shaft is connected to the rotation center of the centrifugal drum.

[0065] Step 4: Directly reverse the direction of the fixture 100, and start the driving device again to complete a centrifugal test in another direction, such as the Y2 direction.

[0066] In the above embodiment, the centrifugal tests in multiple directions can be completed without loading and unloading the products to reverse the direction, thereby improving the work efficiency and reducing the appearance defects of the products to be tested caused by fixture wear.

[0067] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present disclosure.

Claims

1. A tooling for hybrid integrated circuit testing, characterized in that, including a fixture (100), the fixture (100) includes a base (110) and a cover plate (120), the base (110) and the cover plate (120) can be covered and form a plurality of accommodation cavities (130), and the accommodation cavities (130) are used to fix the product to be tested; a boss is arranged in the accommodation cavity (130) for supporting the pins of the product to be tested; the base (110) includes a first positioning structure, the cover plate (120) includes a second positioning structure, and the first positioning structure and the second positioning structure can be fitted with each other to position the base (110) and the cover plate (120).

2. The tooling according to claim 1, characterized in that, The base (110) and / or the cover plate (120) includes a groove for forming the accommodation cavity (130).

3. The tooling according to claim 2, characterized in that, The boss includes a first boss (113) and a second boss (122) arranged oppositely, the first boss (113) and the second boss (122) have supporting surfaces parallel to each other for supporting the pins of the product to be tested.

4. The tooling according to claim 3, characterized in that, The base (110) includes a plurality of grooves (112) arranged in an array, and the first boss (113) is arranged at the bottom of the grooves (112); a plurality of the second bosses (122) corresponding to the first bosses (113) one by one are arranged on the cover plate (120).

5. The tooling according to claim 1, wherein The first positioning structure includes four concave structures (111) respectively arranged at the four corners of the base (110); The second positioning structure includes four convex structures (121) respectively arranged at the four corners of the cover plate (120), the convex structures (121) face the covering direction of the base (110) and are adapted to the corresponding concave structures (111).

6. The tooling according to claim 5, characterized in that, Among the first positioning structure and the second positioning structure: one concave structure and the corresponding convex structure have dimensions different from those of the other three concave structures and the corresponding convex structures; or the concave structure and the corresponding convex structure located at one end of the tooling have dimensions different from those of the concave structure and the corresponding convex structure located at the other end of the tooling.

7. The tooling according to claim 2 or 3, characterized in that, The groove (112) includes one or more pick-and-place grooves (115) arranged at the corresponding positions of the side wall of the groove (112) and the shell corner of the product to be tested.

8. The tooling according to any one of claims 1 to 3, characterized in that, At least one of the base (110) and the cover plate (120) is further provided with at least one counterweight hole (114) for adjusting the counterweight of the fixture (100).

9. The tooling according to any one of claims 1-6, characterized in that, It further includes a carrying base (200); the carrying base (200) includes a plurality of fixture carrying grooves (210) and a through groove (220) penetrating the carrying base (200), and the through groove (220) is perpendicular to the fixture carrying grooves (210); the width of the fixture carrying groove (210) is adapted to the width of the fixture (100), and the depth is more than 2 / 3 of the thickness of the carrying base (200).

10. The tooling according to any one of claims 1-6, characterized in that, It further includes a centrifugal drum (300), and a plurality of centrifugal fixing grooves (310) are arranged on the inner side wall of the centrifugal drum (300); the centrifugal fixing grooves (310) can respectively fix the fixture (100) forward or backward.

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