Patent Publication Number: US-10780484-B2

Title: Processing method and apparatus for metal housing

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a 35 U.S.C. § 371 National Phase conversion of International (PCT) Patent Application No. PCT/CN2014/095861, filed on Dec. 31, 2014, the disclosure of which is incorporated by reference herein. The PCT International Patent Application was filed and published in Chinese. 
     TECHNICAL FIELD 
     Embodiments of the present disclosure generally relate to metal housing processing technology, and in particular relate to a processing method and a processing apparatus for a metal housing. 
     BACKGROUND 
     In the prior art, an end face of a metal housing of a data interface normally needs to be chamfered in order to enhance a strength of the end face. In general, the end face of the metal housing having a hole is chamfered using CNC (Computer numerical control). However, for a metal housing having a smaller dimension, it is difficult to reposition the cutter when using the CNC to perform the chamfering, especially perform the chamfering to unnecessary curved surfaces of the metal housing which is thinner in thickness, since unnecessary curved surfaces are uncertain after the curved surface forming of the metal housing. Furthermore, during the processing, the cutter is prone to oscillate since the material of the metal housing is thin, and thus the chamfered slanted surface is prone to be scratched. In this way, the quality of the chamfered slanted surface may be impacted. 
     SUMMARY 
     The technical problem which the present disclosure mainly solves is to provide a processing method and a processing apparatus for a metal housing, which is capable of solving the technical problems that the chamfer processing is difficult and the chamfered slanted surface is prone to be scratched when using CNC. 
     In order to solve the above technical problem, a technical scheme adopted by the present disclosure is to provide a processing method for a metal housing. The method includes: sleeving a metal flat pipe having an end face provided with a curved surface portion on a lower mold; and pressing the curved surface portion by the cooperation between an upper mold and the lower mold, thereby forming a chamfered slanted surface on the curved surface portion. 
     In order to solve the above technical problem, still another technical scheme adopted by the present disclosure is to provide a processing apparatus for a metal housing comprising: a lower mold, configured to fix a metal flat pipe having an end face provided with a curved surface portion; an upper mold, configured to cooperate with the lower mold to press the curved surface portion, in such a way that a chamfered slanted surface is formed on the end face of the metal flat pipe. 
     The present disclosure may achieve the following advantageous effects: different from the prior art, in the processing method and processing apparatus provided in the present disclosure, a metal flat pipe having a curved surface portion provided on an end face may be firstly sleeved on the lower mold, and then the curved surface portion may be pressed by the cooperation between the upper mold and the lower mold; in this way, a chamfered slanted surface may be formed on the curved surface portion. The processing processes and the apparatus involved are simple, the quality of the products is improved, and the method is suitable for mass production. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a flow chart of a first embodiment of a processing method for a metal housing of the present disclosure. 
         FIG. 1A  is a flow chart showing parts of the processing method for a metal housing in  FIG. 1 . 
         FIG. 2  is a flow chart of a second embodiment of a processing method for a metal housing of the present disclosure. 
         FIG. 3  is a flow chart of a third embodiment of a processing method for a metal housing of the present disclosure. 
         FIG. 4  is an exploded view of the first closing mold of a fourth embodiment of a processing apparatus for a metal housing of the present disclosure. 
         FIG. 5  is an exploded view of the second closing mold of a fourth embodiment of a processing apparatus for a metal housing of the present disclosure. 
         FIG. 6  is a stereogram of a first lower mold of the processing apparatus for a metal housing shown in  FIG. 4 . 
         FIG. 7  is a stereogram of a metal flat pipe to be processed of the present disclosure. 
         FIG. 8  is a stereogram of a first upper mold of the processing apparatus for a metal housing shown in  FIG. 4 . 
         FIG. 9  is a partial view of the metal flat pipe after being processed by the first closing mold of the processing apparatus for a metal housing shown in  FIG. 4 . 
         FIG. 10  is a stereogram of a second lower mold of the processing apparatus for a metal housing shown in  FIG. 5 . 
         FIG. 11  is a stereogram of a second upper mold of the processing apparatus for a metal housing shown in  FIG. 5 . 
         FIG. 12  is an exploded view of a fifth embodiment of a processing apparatus for a metal housing of the present disclosure. 
         FIG. 13  is a schematic view showing the stretchable lower mold of the processing apparatus for a metal housing shown in  FIG. 12 , wherein the stretchable lower mold is reset. 
         FIG. 13A  is a schematic view showing the stretchable lower mold of the processing apparatus for a metal housing shown in  FIG. 12 , wherein the stretchable lower mold is stretched out. 
         FIG. 14  is a schematic view showing the stretchable upper mold of the processing apparatus for a metal housing shown in  FIG. 12 , wherein the stretchable upper mold is reset. 
         FIG. 14A  is a schematic view showing the stretchable upper mold of the processing apparatus for a metal housing shown in  FIG. 12 , wherein the stretchable upper mold is stretched out. 
         FIG. 15  is a partial view of the metal flat pipe after being processed by the processing apparatus for a metal housing of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Some terms are used in the specification and claims to indicate specific components. However, one skilled in the art may understand that, manufacturers may use different terms to indicate the same components. In the specification and claims of the present disclosure, the components are distinguished from each other based on the functional differences, rather than the names used here. The present disclosure will now be described in detail in connection with the drawings and embodiments. 
     First Embodiment 
     Referring to  FIG. 1 , a flow chart of a first embodiment of a processing method for a metal housing of the present disclosure is depicted. The processing method for a metal housing of the present embodiment may include the following blocks. 
     At block S 30 : a metal flat pipe having an end face provided with a curved surface portion may be sleeved on a lower mold. 
     At block S 40 : the curved surface portion may be pressed by the cooperation between an upper mold and the lower mold; in this way, a chamfered slanted surface may be formed on the curved surface portion. 
     In the chamfering method of the metal housing provided in the embodiment of the present disclosure, a metal flat pipe having an end face provided with a curved surface portion may be firstly sleeved on a lower mold; and then the curved surface portion may be pressed by the cooperation between an upper mold and a lower mold; in this way, a chamfered slanted surface may be formed on the curved surface portion. The processing processes and the apparatus involved in the method are simple, the quality of the products is improved, and thus the method may be suitable for mass production. 
     In this embodiment, the lower mold may include a first lower mold and a second lower mold. The upper mold may include a first upper mold and a second upper mold. The block S 30  may specifically include: sleeving the curved surface portion of the metal flat pipe on an end face of the first lower mold that has a horn-shaped recess formed thereon; sleeving a first metal section on a first core section; sleeving a second metal section on a second core section, and sleeving a third metal section on a third core section. In this embodiment, the third metal section may be abutted against a fourth core section having a sectional width larger than that of the third core section, thereby preventing the metal flat pipe from sliding axially. 
     Referring to  FIG. 1A , a flow chart showing parts of the processing method for a metal housing in  FIG. 1  is depicted. The block S 40  may specifically include the following blocks. 
     At block S 41 : the curved surface portion may be pressed by the cooperation between the first upper mold and the first lower mold, and thus the chamfered slanted surface and a chamfered surface are formed on the curved surface portion. 
     That is to say, the curved surface portion may be pressed by the cooperation between a boss on an end face of the first upper mold that has a slanted surface and the horn-shaped recess provided on an end face of the first lower mold. In this way, the chamfered slanted surface and the chamfered surface may be formed on the curved surface portion. In specific, the end face of the first upper mold may be provided with an annular depression and a boss arranged in the annular depression, and an outer side of the boss is a slanted surface. The end face of the first lower mold may be provided with a horn-shaped recess. The boss of which the outer side is a slanted surface may cooperate with the horn-shaped recess in order to press the curved surface portion. In this way, the chamfered surface and the chamfered slanted surface connected to the chamfered surface may be formed in the inner side of the curved surface portion. The annular depression may be configured to maintain the outer shape of the curved surface portion. 
     At block S 42 : the metal flat pipe may be sleeved on the second lower mold after the chamfered surface and the chamfered slanted surface are formed on the curved surface portion. 
     In this embodiment, the block specifically includes: sleeving the curved surface portion of the metal flat pipe on an end face of the second lower mold; sleeving the first metal section on a first molding section; sleeving the second metal section on a second molding section, and sleeving the third metal section on a third molding section. In this embodiment, the second lower mold may have a through-hole formed therein. The third metal section may be abutted against the fourth molding section having a sectional width larger than that of the third molding section, thereby preventing the metal flat pipe from sliding axially. 
     At block S 43 : the curved surface portion may be pressed by the cooperation between the second upper mold and the second lower mold, and thus the chamfered surface may be cut off. 
     In this embodiment, the block S 43  may specifically include: cutting off the chamfered surface by the cooperation between an annular cutting edge on the end face of the second upper mold and the through-hole of the second lower mold. 
     Second Embodiment 
     Referring to  FIG. 2 , a flow chart of a second embodiment of a processing method for a metal housing of the present disclosure is depicted. The method of the second embodiment is substantially the same as that of the first embodiment. The difference between these two embodiments may lie in that, the processing method for a metal housing of the second embodiment may further include the following blocks implemented before the block S 30 . 
     At block S 10 : the metal flat pipe may be formed by a circular pipe using pipe-expansion technology. 
     In this embodiment, the block S 10  may specifically include the following blocks. 
     At block S 11 : a metal circular pipe may be provided, and the metal circular pipe may be pressed along a radial direction thereof to form the metal flat pipe. 
     A block S 12 : the metal flat pipe may be sleeved on the core, wherein at least two core sections having different sectional dimensions may be arranged along an axial direction of the core. 
     At block S 13 : the metal flat pipe may be pressed by the cooperation between at least two cavities and corresponding cores, in such a way that the metal flat pipe may be pressed along the axial direction of the core to respectively form metal sections corresponding to the core sections. 
     The block S 13  may be achieved by at least one process selecting from a group consisting of the pipe-expansion process configured to enlarge the sectional dimension of the metal flat pipe, the pipe-narrowing process configured to reduce the sectional dimension of the metal flat pipe, and the pipe-expansion or pipe-narrowing shaping process configured to shape the expanded or narrowed metal flat pipe. In this way, the metal sections having different pipe diameters may be formed by the metal flat pipe. 
     At block S 20 : the curved surface portion may be formed on the end face of the metal flat pipe by the pipe-narrowing technology. 
     In this embodiment, the end face of the metal flat pipe may be pressed by the cooperation between the cavities and the cores, and thus the curved surface portion may be formed on the end face of the metal flat pipe. 
     Third Embodiment 
     Referring to  FIG. 3 , a flow chart of a third embodiment of a processing method for a metal housing of the present disclosure is depicted. The processing method for a metal housing of the third embodiment may include the following blocks. 
     At block S 10 ′: the metal flat pipe may be formed by a circular pipe using pipe-expansion technology. 
     The block S 10 ′ is the same as the block S 10  in the second embodiment. 
     At block S 20 ′: the curved surface portion may be formed on the end face of the metal flat pipe by the pipe-narrowing technology. 
     The block S 20 ′ is the same as the block S 20  in the second embodiment. 
     At block S 50 : the metal flat pipe having the end face provided with a curved surface portion may be sleeved on a fixed mold. 
     In this embodiment, the lower mold may include a fixed mold and a stretchable lower mold, and the upper mold may include a folding mold and a stretchable upper mold. The fixed mold may be stretchably connected to the stretchable lower mold. When the stretchable lower mold is reset, the stretchable lower mold is retracted into the fixed mold, and thus a through-hole on an end face of the fixed mold is blocked and an opening groove is thereby formed. When the stretchable lower mold is stretched in a direction away from the end face of the fixed mold, the through-hole is formed in the fixed mold. 
     The block S 50  may specifically include: sleeving the first metal section on a first core section of the fixed mold; sleeving the second metal section on a second core section of the fixed mold, sleeving the third metal section on a third core section of the fixed mold, and sleeving the curved surface portion of the metal flat pipe on an end face having a through-hole of the fixed mold. In this embodiment, the third metal section may be abutted against a fourth core section having a sectional width larger than that of the third core section, thereby preventing the metal flat pipe from sliding axially. 
     At block S 60 : the metal flat pipe may be pressed by the cooperation between the folding mold and the fixed mold, in such a way that a chamfered slanted surface and a chamfered surface may be formed on the curved surface portion. 
     In this embodiment, the folding mold may be stretchably connected to the stretchable upper mold. An annular depression may be formed on an end face of the folding mold, and a top cutting edge may be provided on an end face of the stretchable upper mold. When the stretchable upper mold is reset, the stretchable upper mold is retracted into the folding mold, and thus the end face of the stretchable upper mold may protrude out of the annular depression. When the stretchable upper mold is stretched out of the end face of the folding mold, the end face of the stretchable upper mold may stretch to the through-hole in the fixed mold. In this embodiment, the annular depression includes an outer ring curved surface, an inner ring slanted surface, and a concave surface formed between the outer ring curved surface and inner ring slanted surface. 
     The block S 60  may specifically include: resetting the stretchable upper mold and the stretchable lower mold; protruding the end face of the stretchable upper mold out of the concave surface, and aligning the end face of the stretchable upper mold with an edge of the inner ring slanted surface; forming an opening groove by the stretchable lower mold and the fixed mold during the resetting of the stretchable lower mold; pressing the curved surface portion by the cooperation between the end face of the stretchable upper mold that protrudes out of the concave surface, thereby forming the chamfered slanted surface and the chamfered surface on the curved surface portion. In specific, when the curved surface portion is pressed by the cooperation between the annular slanted surface of the folding mold and the inner ring slanted surface of the folding mold, the chamfered slanted surface may be formed. When the curved surface portion is pressed by the cooperation between the end face of the stretchable upper mold and the opening groove formed by the stretchable lower mold, the chamfered surface may be formed. 
     At block S 70 : the stretchable lower mold may be stretched in a direction away from the end face of the folding mold. 
     In this embodiment, a through-hole may be formed in the fixed mold when the stretchable lower mold is stretched out of the fixed mold. 
     At block S 80 : the stretchable upper mold may be stretched out of the end face of the folding mold and further stretched into the inner side of the fixed mold, and thus the chamfered surface may be cut off by the stretchable upper mold. 
     In this embodiment, a top cutting edge configured to cut off the chamfered surface may be formed on the end portion of the stretchable upper mold. Accordingly, the block S 80  may specifically include: stretching the stretchable upper mold of the end face of the folding mold and further into the through-hole of the fixed mold, thereby cutting off the chamfered surface by the top cutting edge. 
     Fourth Embodiment 
     Referring to  FIG. 4 , an exploded view of the first closing mold of a fourth embodiment of a processing apparatus for a metal housing of the present disclosure is depicted. Referring to  FIG. 5 , an exploded view of the second closing mold of a fourth embodiment of a processing apparatus for a metal housing of the present disclosure is depicted. 
     The present disclosure further provides a processing apparatus for a metal housing. The apparatus may include a lower mold and an upper mold. The lower mold may be configured to fix the metal flat pipe having a curved surface portion on the end face. The curved surface portion may be pressed by the cooperation between the upper mold and the lower mold, in such a way that the chamfered slanted surface may be formed on the end face of the metal flat pipe. As is shown in  FIG. 4  and  FIG. 5 , the lower mold of the present embodiment may include a first lower mold  100  and a second lower mold  300 , and the upper mold may include a first upper mold  200  and a second upper mold  400 . In this embodiment, the first lower mold  100  and the first upper mold  200  together forms a first closing mold, and the second lower mold  300  and the second upper mold  400  together forms a second closing mold. 
     Referring to  FIG. 6 , a stereogram of a first lower mold of the processing apparatus for a metal housing shown in  FIG. 4  is depicted. The first lower mold  100  may include an end face having a horn-shaped recess  101 , a first core section  110 , a second core section  120 , a third core section  130  and a fourth core section  140  which are subsequently connected with one another. The end face is connected to the first core section  110 . 
     Referring to  FIG. 7 , a stereogram of a metal flat pipe to be processed of the present disclosure is depicted. The metal flat pipe  500  may include a first metal section  510 , a second metal section  520  and a third metal section  530 . The first metal section  510  may be sleeved on the first core section  110 , the second metal section  520  may be sleeved on the second core section  120 , and the third metal section  530  may be sleeved on the third core section  130 . A curved surface portion  501  may be sleeved on the end face having a horn-shaped recess  101 . The third metal section  530  may be abutted against the fourth core section  140  having a sectional width larger than that of the third core section  130 , thereby preventing the metal flat pipe  500  from sliding axially. It should be noted that, the sectional widths respectively of the metal sections each are different from each other. In specific, a sectional width of the first metal section  510  is smaller than that of the second metal section  520 , and the sectional width of the second metal section  520  is smaller than that of the third metal section  530 . The sectional width of the second metal section  520  is reduced gradually in a direction towards the first metal section. Of course, in other embodiments, the sectional widths respectively of the metal sections each may be varied irregularly, and the sectional widths will not be specifically limited in the present disclosure. However, an inner wall of each of the metal sections should be adhered to an outer wall of the corresponding core sections of the first lower mold  100 . 
     Referring to  FIG. 8  and  FIG. 9 , in  FIG. 8 , a stereogram of a first upper mold of the processing apparatus for a metal housing shown in  FIG. 4  is depicted; in  FIG. 9 , a partial view of the metal flat pipe after being processed by the first closing mold of the processing apparatus for a metal housing shown in  FIG. 4  is depicted. The end face of the first upper mold  200  may be provided with an annular depression  201  and a boss  202  arranged in the annular depression  201 , and the outer side of the boss  202  may be a slanted surface. In this embodiment, an outer ring edge of the annular depression  201  may be at a level higher than an inner ring edge thereof. The inner ring edge may be integrated with the slanted boss  202 , in such a way that the annular depression  201  having a certain height is formed between the outer ring edge and the inner ring edge. As is shown in  FIG. 9 , the curved surface portion  501  is pressed by the cooperation between the boss  202  and the horn-shaped recess  101 , and thus a chamfered surface  503  and a chamfered slanted surface  502  subsequently connected with one another may be formed in the inner side of the curved surface portion  501 . The annular depression  201  helps to maintain the outer shape of the curved surface portion  501 . 
     The first lower mold  100  is configured to fix the metal flat pipe  500  having an end face provided with a curved surface portion  501 . The curved surface portion  501  may be pressed by the cooperation between the first upper mold  200  and the first lower mold  100 , and the chamfered slanted surface  502  and the chamfered surface  503  as is shown in  FIG. 9  may be formed on the end face of the metal flat pipe  500 . The second lower mold  300  may be configured to fix the metal flat pipe  500  having the chamfered slanted surface  502  and the chamfered surface  503 . The second upper mold  400  cooperates with the second lower mold  300  in order to cut off the chamfered surface  503 . 
     Referring to  FIG. 10 , a stereogram of a second lower mold of the processing apparatus for a metal housing shown in  FIG. 5  is depicted. The second lower mold  300  may include a first molding section  310 , a second molding section  320 , a third molding section  330  and a fourth molding section  340  which are subsequently connected with one another and which respectively have a through-hole  301 . The first metal section  510  may be sleeved on the first molding section  310 , the second metal section  520  may be sleeved on the second molding section  320 , the third metal section  530  may be sleeved on the third molding section  330 , and the curved surface portion  501  having the chamfered slanted surface  502  and the chamfered surface  503  provided thereon may be sleeved on an end face of the second lower mold  300 . The third metal section  530  may be abutted against the fourth molding section  340  having a sectional width larger than that of the third molding section  330 , thereby preventing the metal flat pipe  500  from sliding axially. 
     Referring to  FIG. 11 , a stereogram of a second upper mold of the processing apparatus for a metal housing shown in  FIG. 5  is depicted. An annular cutting edge  401  is formed on the end face of the second upper mold  400 . The annular cutting edge  401  cooperates with the through-hole  301  of the second lower mold  300  in order to cut off the chamfered surface  503 . 
     Fifth Embodiment 
     Referring to  FIG. 12 , an exploded view of a fifth embodiment of a processing apparatus for a metal housing of the present disclosure is depicted. 
     The processing apparatus for a metal housing of the fifth embodiment is substantially the same as that of the fourth embodiment. The difference between these two embodiments lies in that, the processing apparatus for a metal housing in the fifth embodiment does not include the second upper mold  300  and the second lower mold  400 ; instead, a stretchable lower mold  300 ′ is arranged in the fixed mold  100 ′, and a stretchable upper mold  400  is arranged in the folding mold  200 ′ in this embodiment. In specific, as is shown in  FIG. 12 , the lower mold of the processing apparatus for a metal housing of the fifth embodiment may include a fixed mold  100 ′ and a stretchable lower mold  300 ′, and the upper mold may include a folding mold  200 ′ and a stretchable upper mold  400 ′. The stretchable upper mold  400 ′ may be stretchably connected to the folding mold  200 ′ via a cylinder and the stretchable lower mold  300 ′ may be stretchably connected to the fixed mold  100 ′ via a cylinder. Of course, in other embodiment, it is also possible to stretchably connect the fixed mold  100 ′ to the stretchable lower mold  300 ′ and stretchably connect the folding mold  200 ′ to the stretchable upper mold  400 ′ via any other suitable driving device, such as a hydraulic cylinder and the like. When the fixed mold  100 ′ and the stretchable lower mold  300 ′ are reset, the end face of the fixed mold  100 ′ matching with the stretchable lower mold  300 ′ is in the same shape as the end face of the first lower mold  100  of the fourth embodiment. When the folding mold  200 ′ and the stretchable upper mold  400 ′ are reset, the end face of the folding mold  200 ′ matching with the stretchable upper mold  400 ′ is in the same shape as the end face of the first upper mold of the fourth embodiment. 
     Referring to  FIGS. 13 and 13A , in  FIG. 13 , a schematic view showing the stretchable lower mold of the processing apparatus for a metal housing shown in  FIG. 12  is depicted, wherein the stretchable lower mold is reset. In  FIG. 13A , a schematic view showing the stretchable lower mold of the processing apparatus for a metal housing shown in  FIG. 12  is depicted, wherein the stretchable lower mold is stretched out. The fixed mold  100 ′ of the present embodiment is in the same shape as the first lower mold  100  of the fourth embodiment of the processing apparatus for a metal housing. The difference between these two embodiments lies in that, a through-hole  301 ′ passing through the end face may be further formed in the fixed mold  100 ′ of the present embodiment. The edge of the through-hole  301 ′ may be an annular slanted surface  102 ′. When the stretchable lower mold  300 ′ is reset and retracted back into the fixed mold  100 ′, the through-hole  301 ′ may be blocked, and thus the annular slanted surface  102 ′ and the end face of the stretchable lower mold  300 ′ together form an opening groove  101 ′. As is shown in  FIG. 13A , when the stretchable lower mold  300 ′ is stretched along the direction A, the stretchable lower mold  300 ′ is moved away from the end face of the fixed mold  100 ′, and thus the through-hole  301 ′ passing through the end face may be formed in the fixed mold  100 ′. 
     Referring to  FIGS. 14 and 14A , in  FIG. 14 , a schematic view showing the stretchable upper mold of the processing apparatus for a metal housing shown in FIG.  12  is depicted, wherein the stretchable upper mold is reset. In  FIG. 14A , a schematic view showing the stretchable upper mold of the processing apparatus for a metal housing shown in  FIG. 12  is depicted, wherein the stretchable upper mold is stretched out. The folding mold  200 ′ of the present embodiment is in the same shape as the first upper mold  200  of the fourth embodiment of the processing apparatus for a metal housing. The difference between these two embodiments lies in that, a through-hole passing through the end face is further formed in the folding mold  200 ′ of the present embodiment. In this embodiment, the end face of the folding mold  200 ′ may have an annular depression  201 ′ formed thereon, wherein the annular depression  201 ′ may include an outer ring curved surface  203 , an inner ring slanted surface  204 , and a concave surface formed between the outer ring curved surface  203  and inner ring slanted surface  204 . A top cutting edge may be formed on the end face  401 ′ of the stretchable upper mold  400 ′. When the stretchable upper mold  400 ′ is reset, the stretchable upper mold  400 ′ may be retracted into the folding mold  200 ′, and thus the end face  401 ′ of the stretchable upper mold  400 ′ may be protruded out of the concave surface and further aligned with the inner ring slanted surface  204 . When the stretchable upper mold  400 ′ is stretched out of the end face of the folding mold  200 ′, the end face  401 ′ of the stretchable upper mold  400 ′ may be stretched into the inner side of the fixed mold  100 ′. 
     When the stretchable upper mold  400 ′ is reset, the end face  401 ′ of the stretchable upper mold  400 ′ may be protruded out of the annular depression  201 ′. In specific, the end face  401 ′ of the stretchable upper mold  400 ′ may be protruded out of the concave surface, and further aligned with the inner ring slanted surface  204 . When the stretchable lower mold  300 ′ is reset, the stretchable lower mold  300 ′ and the fixed mold  100 ′ may together form an opening groove  101 ′. The opening groove  101 ′ may be pressed by the end face  401 ′ aligned with the inner ring slanted surface  204 , and thus the chamfered slanted surface  502  and the chamfered surface  503  as is shown in  FIG. 9  may be formed on the curved surface portion  501 . In specific, when the curved surface portion  501  is pressed by the cooperation between the annular slanted surface  102 ′ of the fixed mold  100 ′ and the inner ring slanted surface  204  of the folding mold  200 ′, the chamfered slanted surface  502  may be formed. When the curved surface portion  501  is pressed by the cooperation between the end face of the stretchable upper mold  400 ′ and the opening groove  101 ′ formed by the stretchable lower mold  300 ′, the chamfered surface  503  may be formed. 
     As is shown in  FIG. 13A , the stretchable lower mold  300 ′ may be stretched in a direction away from the end face of the fixed mold  100 ′ along the direction A, and thus the through-hole  301 ′ may be formed in the fixed mold  100 ′. As is shown in  FIG. 14A , the stretchable upper mold  400 ′ may be stretched out of the end face of the folding mold  200 ′ along a direction B, and further stretched to the through-hole  301 ′ of the fixed mold  100 ′. In this way, the top cutting edge may cut off the chamfered surface  503 , and thus the end face of the metal flat pipe  500  only has the chamfered slanted surface  502  (as is shown in  FIG. 15 ) formed thereon. 
     It should be noted that, slopes respectively of the annular slanted surface  102 ′, the inner ring slanted surface  204 , and the slanted surface on the outer side of the boss  202  may be selected based on the required dimension of the chamfer of the metal flat pipe. In the present disclosure, a thickness of the metal flat pipe  500  to be processed may be optionally 0.15 mm, and the dimension of the chamfer formed on the curved surface portion  501  of the processed metal flat pipe  500  may be optionally 45 degrees×0.1 mm. Of course, in other embodiments, any suitable thickness and dimension of the chamfer of the metal flat pipe may be selected. For example, the thickness of the metal flat pipe  500  may be 0.1 mm, and the dimension of the chamfer may be 30 degrees×0.06 mm. 
     In other embodiment, the processing apparatus for a metal housing may further include a pipe-expansion mechanism and a pipe-narrowing mechanism. The pipe-expansion mechanism may be configured to process the circular pipe into the metal flat pipe  500 . The pipe-narrowing mechanism may be configured to form the curved surface portion  501  on the end face of the metal flat pipe  500 . 
     The pipe-expansion mechanism and the pipe-narrowing mechanism may respectively include at least two cavities and two cores. The metal flat pipe  500  may be pressed by the cooperation between the cavities and the cores in order to form the metal sections having different pipe diameters. In specific, the pipe-expansion mechanism and the pipe-narrowing mechanism may use at least one process selecting from a group consisting of the pipe-expansion process configured to enlarge the sectional dimension of the metal flat pipe, the pipe-narrowing process configured to reduce the sectional dimension of the metal flat pipe, and the pipe-expansion or pipe-narrowing shaping process configured to shape the expanded or narrowed metal flat pipe. In this way, the metal sections having different pipe diameters may be formed by the metal flat pipe  500 . 
     The pipe-narrowing mechanism may use the cooperation between the cavities and the cores to press the end face of the metal flat pipe  500 , and thus the curved surface portion  501  may be formed on the end face of the metal flat pipe  500 . 
     The metal flat pipe  500  of the present disclosure may be applied as a data interface of an USB (Universal Serial Bus). The metal flat pipe  500  used as the USB data interface may certainly be applied as the data line of other types. And it will not be specifically limited here. 
     The present disclosure may achieve the following advantageous effects: different from the prior art, in the processing method and processing apparatus provided in the present disclosure, a metal flat pipe having a curved surface portion provided on an end face may be firstly sleeved on the lower mold, and then the curved surface portion may be pressed by the cooperation between the upper mold and the lower mold; in this way, a chamfered slanted surface may be formed on the curved surface portion. The processing processes and the apparatus involved are simple, the quality of the products is improved, and the method is suitable for mass production. 
     The foregoing is merely embodiments of the present disclosure, and is not intended to limit the scope of the present disclosure. Any equivalent structure or flow transformation made based on the specification and the accompanying drawings of the present disclosure, or any direct or indirect applications of the disclosure on other related fields, shall all be covered within the protection of the present disclosure.