A high-rigidity, anti-bending PVC modified chip packaging tube

Abstract

The present invention belongs to the technical field of packaging tubes, and discloses a high-rigidity anti-bending PVC modified chip packaging tube, including an inner core tube sheet, the outer surface of the inner core tube sheet is fixedly sleeved with an outer tube sheet, the outer surface of the outer tube sheet is fixedly sleeved with a protective sleeve, and a reinforcing rod is sleeved between the protective sleeve and the outer tube sheet, and the reinforcing rod is annularly distributed between the protective sleeve and the outer tube sheet. The present invention adds annularly distributed reinforcing rods in the packaging tube, and uses a built-in metal woven mesh to comprehensively improve the overall rigidity of the packaging tube to avoid structural deformation and bending under the action of external forces. At the same time, with a protective sleeve made of POM, a high-density, high-crystallinity thermoplastic engineering plastic made of POM is used to ensure that the outer side of the packaging tube is non-metallic material while having good structural strength, avoiding oxidation of internal metal parts while assisting in improving the actual rigidity and anti-bending type of the actual packaging tube. The actual modified packaging tube has a good protection effect and a good use effect.

Description

Technical Field

[0001] The invention belongs to the technical field of packaging tubes, and in particular relates to a high-rigidity anti-bending PVC modified chip packaging tube. Background Art

[0002] Packaging tubes are made of plastic materials and can be designed into different shapes according to their use. They are used to transport electronic devices, package and protect circuit facilities, etc. Polyvinyl chloride (PVC) is a polymer formed by the polymerization of vinyl chloride monomer (VCM) in the presence of initiators such as peroxides and azo compounds or under the action of light or heat according to the free radical polymerization mechanism. Vinyl chloride homopolymers and vinyl chloride copolymers are collectively referred to as vinyl chloride resins. Commonly used packaging tubes are usually made of simple PVC materials.

[0003] In the prior art, PVC packaging tubes are usually made of PVC as the inner core during use. During the packaging and protection of electronic devices such as circuits, the packaging tube is easily bent and deformed due to the structural strength of PVC under the action of external forces, which in turn causes the electrical devices protected in the packaging tube to deform and bend. The packaging protection of electronic devices is actually prone to failure and damage under the action of external forces during transportation or use. The packaging protection effect of the packaging tube is limited and the use effect is poor.

[0004] In addition, during the use of the PVC packaging tube in the prior art, after the packaging tube completes the packaging protection of the electronic devices, the heat generated by the electronic devices packaged inside is not easy to dissipate during use, thereby forming a high-temperature environment in the packaging tube. In addition, due to the annular packaging sealing protection effect of the packaging tube, the actual packaging tube has a certain thickness, and it is difficult to achieve effective and convenient heat dissipation of the electronic devices in the packaging tube. In addition, the heat dissipation effect cannot be effective, which greatly reduces the working stability of the electronic devices inside the packaging tube. Summary of the invention

[0005] The object of the present invention is to provide a high-rigidity and anti-bending PVC modified chip packaging tube to solve the problems raised in the above background technology.

[0006] In order to achieve the above-mentioned purpose, the present invention provides the following technical scheme: a high-rigidity anti-bending PVC modified chip packaging tube, comprising an inner core tube segment, the outer surface of the inner core tube segment is fixedly sleeved with an outer tube segment, the outer surface of the outer tube segment is fixedly sleeved with a protective sleeve, a reinforcing rod is sleeved between the protective sleeve and the outer tube segment, the reinforcing rod is annularly distributed between the protective sleeve and the outer tube segment, the inner surface of the outer tube segment is fixedly sleeved with a metal woven mesh, the metal woven mesh is fixedly sleeved on the outer side of the inner core tube segment, a connecting block is fixedly connected between the metal woven mesh and the reinforcing rod, the inner surface of the inner core tube segment is provided with a lubricating layer, the inner surface of the inner core tube segment is provided with a No. 1 hole, the inside of the protective sleeve is fixedly sleeved with a connecting pipe,

[0007] The reinforcing rod is provided with an inner cavity inside, and the outer surface of the reinforcing rod is provided with side holes and through holes respectively, and the side holes and through holes are both connected with the inner cavity, and the side holes and through holes are respectively located at the bottom and the top of the reinforcing rod, and the outer surface of the outer pipe segment is provided with sleeve holes and connecting holes respectively, and the connecting holes are connected with the side holes, and the inner surface of the sleeve holes is fixedly sleeved with the connecting block, and the top end of the connecting pipe is threadedly sleeved with a sealing cover, and the bottom end of the connecting pipe is connected with the through hole, and the outer surface of the protective sleeve is provided with a reserved hole, and the reserved hole is located on the outside of the connecting pipe, and the diameter of the reserved hole is larger than the diameter of the sealing cover.

[0008] The airflow is passed into the inner cavity 9 inside a group of reinforcing rods 6 through the connecting pipe 18, so that the input airflow in the inner cavity 9 is passed into the metal woven mesh 4 through the side holes 10 and the connecting holes 11. Combined with the air permeability of the metal woven mesh 4, the input airflow is able to flow around through the metal woven mesh 4 to the No. 1 hole 12 in the inner core tube segment 1.

[0009] Preferably, the inner core segment and the outer segment are made of the same material, both of which are made of PVC, and the inner surface of the outer segment is provided with a mounting groove, and the inner surface of the mounting groove is fixedly connected to the metal woven mesh.

[0010] Preferably, a first arc groove is provided on the outer surface of the outer tube segment, a second arc groove is provided on the inner surface of the protective sleeve, the first arc groove and the second arc groove are both located on the outside of the reinforcing rod, and the protective sleeve is made of POM material.

[0011] Preferably, a No. 1 reserved groove is provided on the inner surface of the inner core segment, and the No. 1 reserved groove is connected to the No. 1 hole.

[0012] Preferably, the lubricating layer is made of molybdenum disulfide, and the inner surface of the lubricating layer is respectively provided with a No. 2 hole and a No. 2 reserved groove, the No. 2 hole and the No. 2 reserved groove are connected, the No. 2 hole and the No. 1 hole have the same size and correspond one-to-one, and the No. 2 reserved groove corresponds one-to-one to the No. 1 reserved groove.

[0013] The beneficial effects of the present invention are as follows:

[0014] 1. The present invention adds annular reinforcing rods in the packaging tube and uses a built-in metal woven mesh to comprehensively improve the overall rigidity of the packaging tube to avoid structural deformation and bending under the action of external force. At the same time, the protective cover made of POM is used. High-density, high-crystallinity thermoplastic engineering plastics made of POM are used to ensure that the outer side of the packaging tube is made of non-metallic material while having good structural strength, avoid oxidation of internal metal parts, and assist in improving the actual rigidity and bending resistance of the actual packaging tube. The modified packaging tube has good protection effect and good use effect.

[0015] 2. The present invention adds a lubricating layer on the inner surface of the inner core tube segment, and cooperates with the solid lubricating layer supported by molybdenum disulfide, so that the inner surface of the inner core tube segment inside the packaging tube has good lubricity. When the electronic device is actually installed inside the packaging tube, combined with the actual high lubricity effect, the actual insertion smoothness of the electronic device is greatly improved, the actual insertion is convenient and simple, and the jamming caused by blockage is effectively reduced. The friction is reduced while the lubrication is improved, and the wear on the electronic device during assembly is reduced. The actual assembly is convenient and stable, and the use effect is good.

[0016] 3. The present invention utilizes the inner cavity inside the reinforcing rod, and the through holes and side holes respectively opened on the upper and lower sides of the reinforcing rod, utilizes an external air supply mechanism and a connecting pipe to introduce the flowing airflow for cooling into the inner cavity, and cooperates with a breathable metal woven mesh to distribute the incoming airflow to the No. 1 hole of the inner core tube segment, cooperates with the No. 1 reserved groove to allow the input airflow to fully exchange heat with the internal electronic components, and finally utilizes the gap between the electrical components and the packaging tube and the No. 1 reserved groove and the No. 2 reserved groove to blow out, thereby completing effective cooling treatment when the electrical components are packaged inside the packaging tube, greatly reducing the risk of electrical component failure under high-temperature operation, and the actual cooling is convenient and effective, with good use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention;

[0018] Figure 2 A schematic diagram of a longitudinal section of the present invention;

[0019] Figure 3 for Figure 2 A schematic diagram of the structure enlargement at the center A;

[0020] Figure 4 A schematic diagram of a cross section of the present invention;

[0021] Figure 5 It is a schematic diagram of the explosion between the reinforcing rod and the outer segment of the present invention;

[0022] Figure 6 is a schematic diagram of a protective cover of the present invention;

[0023] Figure 7 It is a schematic diagram of the connection between the metal braided mesh and the reinforcing rod of the present invention;

[0024] Figure 8 It is a schematic diagram of the inner core segment of the present invention;

[0025] Fig. 9 Schematic diagram of the lubricating layer of the present invention.

[0026] In the figure: 1. inner core segment; 2. outer segment; 3. protective cover; 4. metal braided mesh; 5. connecting block; 6. reinforcing rod; 7. arc groove No. 1; 8. arc groove No. 2; 9. inner cavity; 10. side hole; 11. connecting hole; 12. hole No. 1; 13. reserved groove No. 1; 14. lubricating layer; 15. hole No. 2; 16. reserved groove No. 2; 17. through hole; 18. connecting pipe; 19. sealing cover; 20. reserved hole; 21. sleeve hole; 22. installation groove. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] like Figures 1 to 9 As shown, an embodiment of the present invention provides a high-rigidity, anti-bending PVC modified chip packaging tube, comprising an inner core tube segment 1, an outer tube segment 2 is fixedly sleeved on the outer surface of the inner core tube segment 1, a protective sleeve 3 is fixedly sleeved on the outer surface of the outer tube segment 2, a reinforcing rod 6 is sleeved between the protective sleeve 3 and the outer tube segment 2, the reinforcing rod 6 is annularly distributed between the protective sleeve 3 and the outer tube segment 2, a metal woven mesh 4 is fixedly sleeved on the inner surface of the outer tube segment 2, the metal woven mesh 4 is fixedly sleeved on the outer side of the inner core tube segment 1, a connecting block 5 is fixedly connected between the metal woven mesh 4 and the reinforcing rod 6, a lubricating layer 14 is provided on the inner surface of the inner core tube segment 1, a No. 1 hole 12 is opened on the inner surface of the inner core tube segment 1, and a connecting pipe 18 is fixedly sleeved inside the protective sleeve 3.

[0029] First embodiment: During the installation process, the inner core segment 1 is located in the inner layer of the packaging tube, and a metal braided mesh 4 is added to the outer surface of the inner core segment 1, so that the metal braided mesh 4 is fixedly sleeved in the installation groove 22 inside the outer segment 2, and the connecting block 5 is fixedly sleeved in the sleeve hole 21 of the outer segment 2 and fixedly connected to the metal braided mesh 4, so that the outer segment 2 is fixedly sleeved on the outside of the inner core segment 1, and the reinforcing rod 6 is placed in the second arc groove 8 inside the protective cover 3. After the fixed connection is completed, the protective cover 3 is fixedly sleeved on the outside of the outer segment 2, and a lubricating layer 14 is added to the inner surface of the inner core segment 1. After the assembly is completed, the electronic device is placed inside the inner core segment 1 of the packaging tube. When subjected to external force, the protective cover 3, the internal reinforcing rod 6 and the internal metal braided mesh 4 in the packaging tube simultaneously resist the external force, so that the packaging tube maintains a stable structure without deformation or bending.

[0030] Firstly, by adding annularly distributed reinforcing rods 6 in the packaging tube and using the built-in metal woven mesh 4 to comprehensively improve the overall rigidity of the packaging tube, structural deformation and bending under the action of external force can be avoided. At the same time, the protective cover 3 made of POM is used, and the high-density, high-crystallinity thermoplastic engineering plastic made of POM is used to ensure that the outer side of the packaging tube is made of non-metallic material while having good structural strength, avoiding oxidation of internal metal parts while assisting in improving the actual rigidity and bending resistance of the actual packaging tube. The modified packaging tube has good protection effect and good use effect.

[0031] In addition, by adding a lubricating layer 14 to the inner surface of the inner core tube segment 1, combined with the solid lubricating layer 14 supported by molybdenum disulfide, the inner surface of the inner core tube segment 1 inside the packaging tube has good lubricity. When the electronic device is actually loaded into the packaging tube, combined with the actual high lubricity effect, the smoothness of the actual electronic device is greatly improved, and the actual insertion is convenient and simple, which effectively reduces the jamming caused by blockage, and reduces friction while improving lubrication, thereby reducing the wear on the electronic device when assembling the electronic device. The actual assembly is convenient and stable, and the use effect is good.

[0032] like Figure 1 , Figure 2 , Figure 4 , Figure 5 and Figure 6As shown, the inner core segment 1 and the outer segment 2 are made of the same material, and both are made of PVC. The inner surface of the outer segment 2 is provided with a mounting groove 22, and the inner surface of the mounting groove 22 is fixedly sleeved with the metal woven mesh 4. The outer surface of the outer segment 2 is provided with a No. 1 arc groove 7, and the inner surface of the protective cover 3 is provided with a No. 2 arc groove 8. The No. 1 arc groove 7 and the No. 2 arc groove 8 are both located on the outside of the reinforcing rod 6. The protective cover 3 is made of POM material. The interior of the reinforcing rod 6 is provided with an inner cavity 9, and the outer surface of the reinforcing rod 6 is provided with side holes 10 and through holes 17, respectively. The side holes 10 and the through holes 17 are both connected to the inner cavity 9, and the side holes 10 and the through holes 17 are respectively located at the bottom and the top of the reinforcing rod 6.

[0033] During use, the installation and socketing of the metal braided mesh 4 are facilitated by separating the inner core tube sheet 1 and the outer tube sheet 2. The metal braided mesh 4 is used to improve the structural strength and toughness of the packaging tube on the one hand, and to facilitate the passage of the subsequent heat dissipation airflow by utilizing the air permeability. By utilizing the No. 1 arc groove 7 and the No. 2 arc groove 8 to adapt the installation and socketing of the reinforcing rod 6, and utilizing the reinforcing rod 6 made of metal, the overall structural strength and rigidity of the packaging tube are improved to avoid bending. By utilizing the inner cavity 9 in the reinforcing rod 6, while being connected with the connecting tube 18, it is convenient to cooperate with the side holes 10 and the connecting holes 11 to complete the guiding and conveying of the airflow, thereby ensuring that the heat dissipation airflow is stably guided to the internal electronic devices.

[0034] like Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the outer surface of the outer tube segment 2 is respectively provided with a sleeve hole 21 and a connecting hole 11, the connecting hole 11 is connected with the side hole 10, the inner surface of the sleeve hole 21 is fixedly sleeved with the connecting block 5, the top end of the connecting pipe 18 is threadedly sleeved with a sealing cover 19, the bottom end of the connecting pipe 18 is connected with the through hole 17, and the outer surface of the protective sleeve 3 is provided with a reserved hole 20, the reserved hole 20 is located on the outside of the connecting pipe 18, and the diameter of the reserved hole 20 is larger than the diameter of the sealing cover 19.

[0035] During use, the airflow is guided by utilizing the connection between the connecting hole 11 and the side hole 10, and the connection block 5 is fixedly connected to the metal braided mesh 4 and sleeved in the outer tube segment 2 to enhance the connection stability between the metal braided mesh 4 and the outer tube segment 2. The large-diameter reserved hole 20 is utilized to ensure that the sealing cover 19 is hidden inside the protective cover 3 to avoid protrusion, while providing sufficient space for convenient manual operation under concealment.

[0036] like Figure 2 , Figure 8 and Fig. 9As shown, the inner surface of the inner core segment 1 is provided with a No. 1 reserved groove 13, which is connected with the No. 1 hole 12. The lubricating layer 14 is made of molybdenum disulfide. The inner surface of the lubricating layer 14 is provided with a No. 2 hole 15 and a No. 2 reserved groove 16, which are connected with the No. 2 hole 15. The No. 2 hole 15 and the No. 2 reserved groove 16 are the same size as the No. 1 hole 12 and correspond one to one. The No. 2 reserved groove 16 corresponds one to one with the No. 1 reserved groove 13.

[0037] During use, the effective entry of airflow is achieved by utilizing the No. 1 holes 12 annularly distributed on the inner surface of the inner core tube sheet 1, so that the heat exchange airflow is fully exchanged with the heat-generating electronic devices, and after the heat exchange, the No. 1 reserved groove 13 and the No. 2 reserved groove 16 are used to conduct heat dissipation, and the lubricating layer 14 made of molybdenum disulfide greatly improves the internal smoothness, improves the convenience of assembly, and reduces the wear on electrical devices.

[0038] Second embodiment: When it is necessary to perform heat dissipation treatment on the electronic components inside the packaging tube, the sealing cover 19 is rotated open through the reserved hole 20, and the pipeline of the air supply mechanism is connected to the connecting pipe 18, and the external air supply mechanism is started, so that the external air supply mechanism passes the cooling airflow through the connecting pipe 18 into the inner cavity 9 inside a group of reinforcing rods 6, so that the input airflow in the inner cavity 9 passes through the side holes 10 and the connecting holes 11 to the metal woven mesh 4, and with the air permeability effect of the metal woven mesh 4, the input airflow passes through the metal woven mesh 4 and circulates to the No. 1 hole 12 in the inner core tube sheet 1, and exchanges heat with the surface of the internal electronic components through the No. 1 reserved groove 13 and the No. 2 reserved groove 16, and the airflow after heat exchange and temperature increase is discharged through the gap between the packaging tube and the electrical components and the No. 1 reserved groove 13 and the No. 2 reserved groove 16, completing the cooling treatment.

[0039] Firstly, by utilizing the inner cavity 9 inside the reinforcing rod 6, and the through holes 17 and the side holes 10 respectively opened on the upper and lower sides of the reinforcing rod 6, the external air supply mechanism and the connecting pipe 18 are used to introduce the flowing airflow for cooling into the inner cavity 9, and the breathable metal woven mesh 4 is used to distribute the incoming airflow to the No. 1 hole 12 of the inner core tube sheet 1, and the No. 1 reserved groove 13 is used to make the input airflow fully exchange heat with the internal electronic devices, and finally the gap between the electrical device and the packaging tube and the No. 1 reserved groove 13 and the No. 2 reserved groove 16 are used to blow it out, so as to complete the effective cooling treatment when the electrical device is packaged inside the packaging tube, which greatly reduces the risk of failure of the electrical device under high temperature operation, and the actual cooling is convenient and effective, and the use effect is good.

[0040] Working principle and usage process: During the installation process, the inner core segment 1 is located in the inner layer of the packaging tube, and a metal braided mesh 4 is added to the outer surface of the inner core segment 1, so that the metal braided mesh 4 is fixedly sleeved in the installation groove 22 inside the outer segment 2, and the connecting block 5 is fixedly sleeved in the sleeve hole 21 of the outer segment 2 and fixedly connected to the metal braided mesh 4, so that the outer segment 2 is fixedly sleeved on the outside of the inner core segment 1, and the reinforcing rod 6 is placed in the second arc groove 8 inside the protective cover 3. After the fixed connection is completed, the protective cover 3 is fixedly sleeved on the outside of the outer segment 2, and a lubricating layer 14 is added to the inner surface of the inner core segment 1. After the assembly is completed, the electronic device is placed inside the inner core segment 1 of the packaging tube. When subjected to external force, the protective cover 3, the internal reinforcing rod 6 and the internal metal braided mesh 4 in the packaging tube simultaneously resist the external force, so that the packaging tube maintains the structure. The structure is stable without deformation or bending; when it is necessary to perform heat dissipation treatment on the electronic devices inside the packaging tube, the sealing cover 19 is rotated to open through the reserved hole 20, and the pipeline of the air supply mechanism is sleeved with the connecting pipe 18, and the external air supply mechanism is started, so that the external air supply mechanism passes the cooling airflow through the connecting pipe 18 into the inner cavity 9 inside a group of reinforcing rods 6, so that the input airflow in the inner cavity 9 passes through the side holes 10 and the connecting holes 11 to the metal braided mesh 4, and with the air permeability effect of the metal braided mesh 4, the input airflow passes through the metal braided mesh 4 and circulates to the No. 1 hole 12 in the inner core tube sheet 1, and exchanges heat with the surface of the internal electronic device through the No. 1 reserved groove 13 and the No. 2 reserved groove 16, and the airflow after heat exchange and temperature increase is discharged through the gap between the packaging tube and the electrical device and the No. 1 reserved groove 13 and the No. 2 reserved groove 16, completing the cooling treatment.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-rigidity, anti-bending PVC modified chip packaging tube, comprising an inner core tube sheet (1), characterized in that: The outer surface of the inner core segment (1) is fixedly sleeved with an outer segment (2), the outer surface of the outer segment (2) is fixedly sleeved with a protective sleeve (3), a reinforcing rod (6) is sleeved between the protective sleeve (3) and the outer segment (2), the reinforcing rod (6) is annularly distributed between the protective sleeve (3) and the outer segment (2), the inner surface of the outer segment (2) is fixedly sleeved with a metal braided mesh (4), the metal braided mesh (4) is fixedly sleeved on the outer side of the inner core segment (1), a connecting block (5) is fixedly connected between the metal braided mesh (4) and the reinforcing rod (6), the inner surface of the inner core segment (1) is provided with a lubricating layer (14), the inner surface of the inner core segment (1) is provided with a No. 1 hole (12), the inner surface of the protective sleeve (3) is fixedly sleeved with a connecting pipe (18), The reinforcing rod (6) has an inner cavity (9) formed therein, and the outer surface of the reinforcing rod (6) has side holes (10) and through holes (17) formed therein, the side holes (10) and through holes (17) being both connected to the inner cavity (9), the side holes (10) and through holes (17) being located at the bottom and top of the reinforcing rod (6), respectively. The outer surface of the outer tube segment (2) has sleeve holes (21) and connecting holes (11) formed therein, the connecting holes (11) being connected to the side holes (10), the inner surface of the sleeve holes (21) being fixedly sleeved with the connecting block (5), the top end of the connecting pipe (18) being threadedly sleeved with a sealing cover (19), the bottom end of the connecting pipe (18) being connected to the through holes (17), the outer surface of the protective sleeve (3) having a reserved hole (20), the reserved hole (20) being located at the outer side of the connecting pipe (18), the diameter of the reserved hole (20) being larger than the diameter of the sealing cover (19), The airflow is introduced into the inner cavity (9) inside a group of reinforcing rods (6) through the connecting pipe (18), so that the airflow in the inner cavity (9) is introduced into the metal braided mesh (4) through the side hole (10) and the connecting hole (11). With the air permeability of the metal braided mesh (4), the airflow is passed around the metal braided mesh (4) and flows into the No. 1 hole (12) in the inner core tube segment (1).

2. The high-rigidity anti-bending PVC modified chip packaging tube according to claim 1, characterized in that: The inner core segment (1) and the outer segment (2) are made of the same material, and are both made of PVC. An installation groove (22) is provided on the inner surface of the outer segment (2), and the inner surface of the installation groove (22) is fixedly sleeved with the metal braided mesh (4).

3. The high-rigidity anti-bending PVC modified chip packaging tube according to claim 1, characterized in that: The outer surface of the outer tube segment (2) is provided with a first arc groove (7), and the inner surface of the protective sleeve (3) is provided with a second arc groove (8). Both the first arc groove (7) and the second arc groove (8) are located outside the reinforcing rod (6), and the protective sleeve (3) is made of POM material.

4. The high-rigidity anti-bending PVC modified chip packaging tube according to claim 1, characterized in that: The inner surface of the inner core segment (1) is provided with a No. 1 reserved groove (13), and the No. 1 reserved groove (13) is connected to the No. 1 hole (12).

5. The high-rigidity anti-bending PVC modified chip packaging tube according to claim 1, characterized in that: The lubricating layer (14) is made of molybdenum disulfide. The inner surface of the lubricating layer (14) is respectively provided with a No. 2 hole (15) and a No. 2 reserved groove (16). The No. 2 hole (15) and the No. 2 reserved groove (16) are connected. The No. 2 hole (15) and the No. 1 hole (12) have the same size and correspond one-to-one. The No. 2 reserved groove (16) and the No. 1 reserved groove (13) correspond one-to-one.

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