Shell and shell manufacturing method

Abstract

A shell comprises a metal frame with a surrounding hole, an insulator formed inside the metal frame, and a nut placed in the surrounding hole and wrapped by the insulator, wherein the nut comprises a nut body and an internal threaded hole formed in the nut body, and the space between the outer periphery of the nut body and the inner wall surface of the surrounding hole is filled with the insulator to isolate the nut from the metal frame. The present application also provides a shell manufacturing method.

Description

Technical Field

[0001] The present application relates to the fields of metal processing and injection molding, and in particular to a housing and a method for manufacturing the housing. Background Art

[0002] Smart watches are currently a mainstream consumer electronic product. To increase the texture, smart watches have begun to use a large number of metal frames as shells. However, they face the following problems during the manufacturing process: a strap hole for installing a strap is opened in the shell, and the strap is required to be directly locked in the strap hole by screws, and the nut in the strap hole cannot come into contact with the metal shell, and the pulling force of a single nut needs to be above 10KG.

[0003] Usually, there are two solutions for fixing the nut: one is to directly implant the copper nut into the plastic by in-mold injection molding during injection molding. However, this solution makes it difficult to position the nut by in-mold injection molding because the nut is too small, and there is a risk of it falling and damaging the mold; the other is to hot-melt the copper nut into the plastic in the hole of the watch strap, but the tensile force of the hot-melt nut does not reach 10KG. Summary of the invention

[0004] In view of this, it is necessary to provide a housing and a method for manufacturing the housing that can embed the nut efficiently and with low risk.

[0005] In order to solve the above technical problems, the present application provides a shell, including a metal frame with a surrounding hole, an insulator formed on the inner side of the metal frame, and a nut placed in the surrounding hole and wrapped by the insulator, the nut including a nut body and an internal threaded hole opened in the nut body, and the outer periphery of the nut body and the inner wall surface of the surrounding hole are filled with insulator to isolate the nut from the metal frame.

[0006] Preferably, a groove structure is provided on the outer periphery of the nut body, and a non-arc portion is provided on the outer periphery of the nut body in a vertical direction, and both the groove structure and the outer periphery of the non-arc portion are wrapped by the insulator.

[0007] Preferably, an interference head is protruded from the upper end of the nut body, and an interference hole is provided on the metal frame outside the surrounding hole, and the outer periphery of the interference head is fixed to the interference hole.

[0008] Preferably, after the nut body is fixed to the metal frame, the insulator is injection molded, and then the interference head between the metal frame, the outer layer and the nut is removed by cutting.

[0009] In order to solve the above technical problems, the present application also provides a shell manufacturing method, comprising the following steps:

[0010] S10, fixing at least one nut in a metal intermediate piece having an interference hole;

[0011] The nut comprises a nut body and an interference head protruding upward from the nut body, the intermediate piece is provided with a through hole, the through hole comprises an inner surrounding hole and an outer interference hole, the interference head of the nut is riveted and fixed in the interference hole, the nut body is located in the surrounding hole and does not contact the inner wall surface of the surrounding hole;

[0012] S20, performing in-mold injection molding on the intermediate piece equipped with the nut, and forming an insulator that wraps the nut body on the inner side of the metal frame; the insulator fills the gap between the inner wall surface of the surrounding hole and the outer periphery of the nut body;

[0013] S30, cutting the injection-molded intermediate piece to remove the outer layer of the intermediate piece and the interference head of the nut to obtain a finished shell. The intermediate piece becomes a metal frame after removing the outer layer.

[0014] Preferably, the outer layer of the middle piece is the part to be removed, the interference hole is opened on the part to be removed, the middle piece is provided with an installation groove passing through the middle piece on one side of the surrounding hole, the interference hole is provided with a groove on the side facing the installation groove, and a cross beam is provided on the inner side of the groove to make the surrounding hole form a closed-loop structure.

[0015] Preferably, the outer diameter of the interference head is larger than the outer diameter of the nut body, and the outer diameter of the interference head at a side away from the nut body is larger than the outer diameter of the interference head at a side close to the nut body.

[0016] Preferably, a groove structure is provided on the outer periphery of the nut body, and a non-arc portion is provided on the outer periphery of the nut body in a vertical direction, and both the groove structure and the outer periphery of the non-arc portion are wrapped by the insulator.

[0017] Preferably, the outer periphery of the nut body is processed to form a plurality of nano-pores, and the molten plastic material is filled into the nano-pores to enhance the bonding force between the nut body and the insulator.

[0018] Preferably, the housing is a smart watch housing, the mounting groove is a watch strap mounting groove, a nut is injection molded at each end of the mounting groove, and the watch strap is fixed to the nuts by screws.

[0019] The shell and shell manufacturing method of the present application are implemented by opening an interference hole on the middle piece of the metal frame, and a surrounding hole is arranged below the interference hole, and the outer periphery of the nut body of the nut is isolated from the inner wall surface of the surrounding hole, and the interference head at the upper end of the nut body and the interference hole are fixed with each other to facilitate the fixation of the nut during the injection molding process, and then the interference hole and the interference head on the to-be-removed part of the metal frame are removed by metal processing, so as to obtain a shell in which the nut is embedded in the insulator and does not contact the metal frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings described herein are used to provide further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0021] Figure 1 A three-dimensional diagram of the finished shell of this application; Figure 1 for Figure 8 The finished product obtained after cutting process.

[0022] Figure 2 For along Figure 1 A cross-sectional view of the CC dashed line shown;

[0023] Figure 3 for Figure 2 A partial enlarged view of the dotted circle shown;

[0024] Figure 4 A three-dimensional diagram of a nut embedded in the finished shell of this application;

[0025] Figure 5 This is a three-dimensional exploded view of the metal housing and the nut before the housing of this application is injection molded;

[0026] Figure 6 This is a three-dimensional combination diagram of the metal shell and the nut before the shell of this application is injection molded;

[0027] Figure 7 For along Figure 6 A partial enlarged view of the AA dashed line cross-sectional view shown;

[0028] Figure 8 This is a three-dimensional diagram of the shell of this application after injection molding;

[0029] Fig. 9 For along Figure 8 A partial enlarged view of the cross-sectional view taken along the dotted line BB is shown. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions of the present application will be clearly and completely described below in conjunction with the specific embodiments of the present application and the corresponding drawings.

[0031] See also Figures 1 to 4 As shown, the housing of the present application includes a metal frame 10 with a mounting groove 12 , an insulator 20 formed inside the metal frame 10 , and a nut 30 formed inside the insulator 20 and exposed in the mounting groove 12 .

[0032] When the housing is used as a smart watch housing, the mounting groove 12 is a strap mounting hole, and nuts 30 in the insulating member 20 are embedded at both ends of the mounting groove 12 .

[0033] The metal frame 10 also includes an outer surface 11 after CNC finishing. The two ends of the mounting groove 12 are provided with surrounding holes 16 (see Figure 3 , Figure 7 As shown in the figure, the nut 30 is suspended in the surrounding hole 16 and is surrounded by the metal frame 10. After the insulator 30 is injection molded, it is wrapped around the outer periphery of the nut 30, that is, it fills the space between the outer periphery of the nut 30 and the inner wall of the surrounding hole 16, so that the nut 30 and the metal frame 10 are electrically isolated from each other. Before the nut 30 is injection molded, the nut 30 and the part to be removed 10a of the metal frame 10 are in contact and interfere with each other. After the insulator 20 is injection molded, the part that interferes with the nut 30 and the part to be removed 10a is removed by metal cutting to electrically isolate the two from each other. In this way, during the injection molding process, the tiny nut 30 can be fixed on the middle piece 10a of the metal frame 10.

[0034] The nut 30 includes a nut body 31, an internal threaded hole 32 opened above the nut body 31, a groove structure 33 opened on the outer periphery of the nut body 31, and a non-arc surface 34 formed by cutting off part of the nut body 31 in the vertical direction. The groove structure 33 is preferably an annular groove, and the non-arc surface 34 is preferably a plane. The groove structure 33 can increase the bonding surface between the outer surface of the nut 30 and the insulator 20, and the groove structure 33 can be mutually locked with the insulator 20, so that the nut 30 is more tightly combined in the insulator 20. The non-arc surface 34 can prevent the nuts from loosening and rotating in the insulator 20.

[0035] Before injection molding the insulator, the outer surface of the nut body 31 of the nut 30 is chemically corroded or mechanically scraped, and a number of tiny nanopore structures are formed on the outer surface of the nut body 31, so that the plastic material of the insulator 20 is filled into the nanopores, thereby increasing the bonding force between the nut 30 and the insulator 20.

[0036] Please continue reading Figures 5 to 9 , Figure 1 , Figure 2As shown, the shell manufacturing method of the present application includes the following steps:

[0037] S10, installing and fixing the nut 30 in the middle piece 10a of the metal frame 10;

[0038] In this step, the nut 30 also includes an interference head 35 extending upward from the top of the nut body 31, and the interference head 35 is downwardly formed with an opening 37 connected to the internal threaded hole 32, and a slope 36 is formed at the connection between the opening 37 and the internal threaded hole 32. The outer periphery of the interference head 35 is a cylindrical structure. The middle piece 10a of the metal frame 10 also includes a to-be-removed portion 15 located outside the outer surface 11 of the metal frame 10, the groove structure 12 has been opened on the middle piece 10a, and interference holes 151 are opened at both ends of the groove structure 12 on the to-be-removed portion 15 at the position corresponding to the surrounding hole 16, and the interference hole 151 is provided with a groove 152 on the inner side, and a crossbeam 17 constituting an annular hole is provided at the bottom of the groove 152, and the crossbeam 17 is a part of the metal frame 10, and does not belong to the to-be-removed portion 15. The interference hole 151 and the surrounding hole 16 are collectively referred to as a through hole that penetrates the middle piece 10a. A supporting table 153 is formed at the junction of the interference hole 151 and the surrounding hole 16 , that is, the inner diameter of the interference hole 151 is greater than the inner diameter of the surrounding hole 16 .

[0039] The nut 30 is riveted into the interference hole 151 from the outside to the inside. At this time, the interference head 35 is fixed by interference with the inner wall surface of the interference hole 151. The setting of the slot 152 can make the interference hole 151 have a certain elasticity to avoid hard interference to damage the nut 30 or cause position error. The outer diameter of the free end of the interference head 35 is slightly larger than the outer diameter of the side close to the nut body 31. The outer diameter of the interference head 35 is larger than the outer diameter of the nut body 31. At the same time, the inner diameter of the interference hole 151 is also larger at the top and smaller at the bottom to match the interference head 35, forming a guide taper structure, which is convenient for the insertion of the nut 30 and avoids hard interference. Therefore, a step portion 39 is formed below the outer periphery of the interference head 35, and the step portion 39 is supported on the support table 153 at the bottom of the interference hole 151. The nut body 31 is suspended in the surrounding hole 16, and there is a filling gap between the inner wall surface of the surrounding hole 16 and the outer periphery of the nut body 31.

[0040] The outer peripheral surface of the nut 30 is processed to form a plurality of nano-micropores, and the processing can be performed before or after the nut 30 is installed in the intermediate member 10a. The bottom of the internal threaded hole 32 of the nut 30 is closed.

[0041] S20 , performing in-mold injection molding on the intermediate member 10 a of the metal frame 10 equipped with the nut 30 , and forming an insulator 20 that wraps the outer periphery and bottom surface of the nut body 31 inside the metal frame 10 .

[0042] In this step, the molten plastic material is filled into the inner side of the metal frame 10 and the mounting groove 12 to fill the gap between the outer peripheral surface of the nut body 31 and the inner wall surface of the surrounding hole 16 of the metal frame 10 to isolate the nut body 31 from the metal frame 10 .

[0043] S30, cutting the injection molded intermediate piece 10a to remove the to-be-removed portion 15 of the intermediate piece 10a, the interfering head 35 of the nut 30 and part of the insulator 20 to obtain a finished housing.

[0044] When the interference head 35 is cut off, the inclined surface of the junction between the opening 37 and the internal thread hole 32 is exposed, so that the screw can be guided into the internal thread hole 32 when the screw is tightened.

[0045] Cutting processing includes CNC finishing, grinding and polishing and other processes, which will not be described here.

[0046] Thus, the nut 30 embedded in the insulator 20 is obtained without contacting the metal frame 10, and there is no need to separately position the nut 30 with a tiny structure during injection molding, which greatly improves the manufacturing efficiency and avoids damage to the mold.

[0047] The shell and shell manufacturing method of the present application are as follows: a mounting groove 12 is opened on the middle piece 10a of the metal frame 10, and interference holes 151 are opened at both ends of the mounting groove 12, and a surrounding hole 16 is arranged below the interference hole 151, and the outer periphery of the nut body 31 of the nut 30 is isolated from the inner wall surface of the surrounding hole 16, and the interference head 35 at the upper end of the nut body 31 and the interference hole 151 are interfered and fixed with each other, so as to facilitate the fixation of the nut 30 during the injection molding process, and then the interference hole 151 and the interference head 35 on the to-be-removed portion 15 of the metal frame 10 are removed by metal processing, so as to obtain a shell in which the nut 30 is embedded in the insulator 20 and does not contact the metal frame 10.

[0048] The shell and shell manufacturing method of the present application are not only suitable for the shell of smart watches, but can also be widely used in the field of electronic products, such as mobile phone shells, tablet computer shells and other devices.

[0049] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A housing, characterized in that: It includes a metal frame with a surrounding hole, an insulator formed on the inner side of the metal frame, and a nut placed in the surrounding hole and wrapped by the insulator. The nut includes a nut body and an internal threaded hole opened in the nut body. The outer periphery of the nut body and the inner wall surface of the surrounding hole are filled with insulator to isolate the nut from the metal frame. An interference head is protruded from the upper end of the nut body. The metal frame is provided with an interference hole on the outer side of the surrounding hole. The outer periphery of the interference head is fixed to the interference hole to facilitate the fixation of the nut during the injection molding process.

2. The housing according to claim 1, characterized in that A groove structure is provided on the outer periphery of the nut body, and a non-arc portion is provided on the outer periphery of the nut body in a vertical direction. The groove structure and the outer periphery of the non-arc portion are both wrapped by the insulator.

3. The housing according to claim 1, characterized in that After the nut body is fixed to the metal frame, the insulator is injection molded, and then the interference head between the metal frame, the outer layer and the nut is removed by cutting.

4. A method for manufacturing a housing, characterized in that: The steps include: S10, fixing at least one nut in a metal intermediate piece having an interference hole; The nut comprises a nut body and an interference head protruding upward from the nut body, the intermediate piece is provided with a through hole, the through hole comprises an inner surrounding hole and an outer interference hole, the interference head of the nut is riveted and fixed in the interference hole, the nut body is located in the surrounding hole and does not contact the inner wall surface of the surrounding hole; S20, performing in-mold injection molding on the intermediate piece equipped with the nut, and forming an insulator that wraps the nut body on the inner side of the metal frame; the insulator fills the gap between the inner wall surface of the surrounding hole and the outer periphery of the nut body; S30, cutting the injection-molded intermediate piece to remove the outer layer of the intermediate piece and the interference head of the nut to obtain a finished shell. The intermediate piece becomes a metal frame after removing the outer layer.

5. The method for manufacturing a housing as claimed in claim 4, characterized in that: The outer layer of the middle piece is the part to be removed, the interference hole is opened on the part to be removed, the middle piece is provided with a mounting groove passing through the middle piece on one side of the surrounding hole, the interference hole is provided with a groove on the side facing the mounting groove, and a crossbeam is provided on the inner side of the groove to form a closed-loop structure of the surrounding hole.

6. The method for manufacturing a housing as claimed in claim 5, characterized in that: The outer diameter of the interference head is greater than the outer diameter of the nut body, and the outer diameter of the interference head at a side away from the nut body is greater than the outer diameter of the interference head at a side close to the nut body.

7. The method for manufacturing a housing as claimed in claim 5, characterized in that: A groove structure is provided on the outer periphery of the nut body, and a non-arc portion is provided on the outer periphery of the nut body in a vertical direction. The groove structure and the outer periphery of the non-arc portion are both wrapped by the insulator.

8. The method for manufacturing a housing as claimed in claim 5, characterized in that: The outer periphery of the nut body is processed to form a plurality of nanometer micropores, and the molten plastic material is filled into the nanometer micropores to enhance the bonding force between the nut body and the insulator.

9. The method for manufacturing a housing as claimed in claim 5, characterized in that: The housing is a smart watch housing, the mounting groove is a watch strap mounting groove, a nut is injection-molded at each end of the mounting groove, and the watch strap is fixed to the nuts by screws.

Images