A method for manufacturing a confidentiality magnetic head and a confidentiality magnetic head

Abstract

The present invention relates to the technical field of electronic product signal confidentiality, and in particular to a manufacturing method of a confidentiality magnetic head and a confidentiality magnetic head. The preparation method of the present invention changes the existing assembly method from the inside to the outside, firstly the coil is welded on the FPC, then the magnetic sheet group is inserted into the skeleton groove of the coil from both sides, and then the gap sheet and the spring sheet are installed to fix the magnetic sheet group. After the conductive glue is injected into the shoulder of the magnetic sheet group, the outer shell cover is arranged on the magnetic sheet group and the coil. The outer shell and the magnetic sheet group are fixed by conductive glue. In this process, the spring sheet is only used to fix the two magnetic sheet groups without contacting the outer shell. This method can eliminate the adverse effects on the performance of the magnetic head caused by the size change or deformation of the spring sheet, and is suitable for automatic assembly operation, improves production efficiency, and can also reduce the volume of the product, thereby reducing material cost and manufacturing cost.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic product signal confidentiality, and in particular to a manufacturing method of a confidentiality magnetic head and a confidentiality magnetic head. Background Art

[0002] Most existing magnetic heads are assembled from the inside out. In this assembly method, the magnetic sheet group needs to be supported by a magnetic shell, which occupies a large space. The left and right magnetic shells also need to be fixed with springs. The springs need to contact and cooperate with the inner wall of the shell to ensure that the left and right half shells fit tightly and can clamp the gap sheet to ensure that the gap sheet will not fall off. The size of the spring will determine the stability of the shell's pressed-in size and the head's electrical performance, and at the same time play a role in conducting the magnetic sheet group and the shell. In actual production, if the size of the spring changes, the following adverse effects will occur: 1. The spring and shell are assembled too tightly, and the shell is deformed; 2. The spring and shell are assembled loosely, and the pressed-in size cannot be guaranteed, affecting the head inductance; 3. The spring is deformed, and the gap in the middle is large after the left and right half shells are assembled, affecting the head inductance. Summary of the invention

[0003] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a method for manufacturing a confidential magnetic head, which changes the existing assembly method from the inside to the outside, eliminates the adverse effects on the performance of the magnetic head caused by the size change or deformation of the spring piece, is suitable for automated assembly operations, improves production efficiency, and can reduce the volume of the product, thereby reducing material costs and manufacturing costs.

[0004] The technical solution adopted by the present invention to solve the technical problem is: a method for manufacturing a confidential magnetic head, comprising the following steps:

[0005] Solder the FPC and solder the coil to the pad of the FPC;

[0006] Install the magnetic sheet group, insert the two magnetic sheet groups into the skeleton slots from the left and right sides of the coil respectively;

[0007] Inject conductive glue into the shoulders of the magnetic sheet group;

[0008] Install the outer shell, and place the outer shell cover on the coil and the magnetic sheet group, and fix the outer shell and the magnetic sheet group by bonding with conductive glue;

[0009] Separate the magnetic head and FPC from the panel.

[0010] Furthermore, before the step of assembling the magnetic sheet group, a grinding step is also included to grind the assembly surfaces of the magnetic sheets.

[0011] Furthermore, the step of installing the magnetic sheet group also includes the following steps: installing the gap sheet, installing the gap sheet between the assembly surfaces of the two magnetic sheet groups; installing the spring sheet, installing the spring sheet on the two magnetic sheet groups to fix the two magnetic sheet groups and the gap sheet.

[0012] Furthermore, the three spring sheets are sequentially snapped onto the two matching magnetic sheet groups.

[0013] Furthermore, before the step of welding the FPC, a pre-step is also included: using an SMT carrier board to carry the panel, a plurality of FPCs are arranged in an array on the panel, and two adjacent FPCs are arranged head to tail in an alternating manner.

[0014] Furthermore, in the step of installing the outer shell, the lower end of the outer shell passes through the separation portion of the puzzle board and abuts against the avoidance groove of the SMT carrier board.

[0015] Furthermore, in the step of installing the outer shell, the shoulder of the magnetic sheet group is accommodated in the positioning groove inside the outer shell.

[0016] Furthermore, in the step of welding the FPC, there are several welding pads on the FPC, and several pins on a coil are correspondingly welded on several welding pads of one FPC.

[0017] The present invention also provides a confidentiality magnetic head, which can be prepared by the above-mentioned manufacturing method. The confidentiality magnetic head includes: a shell; an FPC, which is welded with at least two coils, and the coils are accommodated in the shell; a magnetic sheet module, which is correspondingly arranged on the coil, including two matching magnetic sheet groups, and the two magnetic sheet groups are respectively inserted into the coil on both sides of the coil; wherein a gap sheet is arranged between the two magnetic sheet groups, and the two magnetic sheet groups are fixedly connected by spring sheets.

[0018] Furthermore, a positioning groove is provided on the shell, and the shoulder of the magnetic sheet group is accommodated in the positioning groove.

[0019] Furthermore, the area between the magnetic sheet group and the positioning groove is injected with conductive glue.

[0020] Furthermore, the spring sheet is inserted from the side between the two magnetic sheet groups and is accommodated in the housing.

[0021] Furthermore, the coil has pins, the FPC has pads, the pins are in a planar bending shape or a vertical shape or a patch shape and are correspondingly welded on the pads.

[0022] Furthermore, the positioning groove is recessed from the inner wall of the shell.

[0023] Furthermore, the assembly surface between the two matching magnetic sheet groups is a polished plane.

[0024] Furthermore, the FPC is fixed on the panel and the coil is fixed to the FPC by welding.

[0025] Furthermore, there are three coils and they are respectively welded on the FPC.

[0026] Furthermore, there are three spring sheets, which are correspondingly snapped into the two matching magnetic sheet groups.

[0027] The beneficial effects of the present invention are as follows: the preparation method of the present invention changes the existing assembly method from the inside to the outside, first the coil is welded on the FPC, then the magnetic sheet group is inserted into the skeleton groove of the coil from both sides, and then the gap sheet and the spring sheet are installed to fix the magnetic sheet group. After the conductive glue is injected into the shoulder of the magnetic sheet group, the outer shell cover is set on the magnetic sheet group and the coil. The outer shell and the magnetic sheet group are bonded and fixed by the conductive glue. In this process, the spring sheet is only used to fix the two magnetic sheet groups without contacting the outer shell. This method can eliminate the adverse effects on the performance of the magnetic head caused by the size change or deformation of the spring sheet, and is suitable for automated assembly operations, improves production efficiency, and can also reduce the volume of the product, thereby reducing material costs and manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0029] Figure 1 is a schematic structural diagram of the preparatory steps of an embodiment of the present invention;

[0030] Figure 2 It is a structural schematic diagram of the steps of welding FPC in an embodiment of the present invention;

[0031] Figure 3 yes Figure 2 A partially enlarged schematic diagram of the above;

[0032] Figure 4 It is a structural schematic diagram of the steps of installing a magnetic sheet group according to an embodiment of the present invention;

[0033] Figure 5 yes Figure 4 A partially enlarged schematic diagram of the above;

[0034] Figure 6 is a structural schematic diagram of a step of installing a housing according to an embodiment of the present invention;

[0035] Figure 7 is a structural assembly diagram of a security magnetic head according to an embodiment of the present invention;

[0036] Figure 8 yes Figure 7 A partially enlarged schematic diagram of the above;

[0037] Fig. 9 It is a cross-sectional schematic diagram of a security magnetic head according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] A method for manufacturing a confidential magnetic head comprises the following steps:

[0040] Preliminary steps, see Figure 1 As shown, an SMT carrier board 700 is used to carry a panel 600, and a plurality of FPCs 500 are arranged in an array on the panel 600, and two adjacent FPCs 500 are arranged head to tail in an alternating manner. In the present embodiment, a separation portion 601 is provided between the FPC 500 and the panel 600, and the width of the separation portion 601 is greater than the wall thickness of the housing 100, so that when the housing 100 is subsequently placed, the housing 100 passes through the panel 600 and abuts against the SMT carrier board 700; one FPC 500 has six symmetrically distributed solder pads 501, and the coil 200 has two pins 201, that is, three coils 200 are correspondingly soldered on one FPC 500.

[0041] Solder FPC500, refer to Figure 2 and Figure 3 As shown, the pins 201 on the coil 200 are correspondingly welded to the pads 501 of the FPC 500. In this embodiment, batch welding can be achieved by patching to improve production efficiency. After welding, the three coils 200 are fixed on the FPC 500, that is, the relative positions of the three coils 200 are fixed, which is convenient for subsequent assembly processes.

[0042] The grinding step is to grind the assembly surface 301 of the magnetic sheet group 300. This step can be performed as a separate process without affecting the assembly process of the main line, thereby improving the efficiency of the main line.

[0043] Install the disk set, refer to Figure 4 and Figure 5As shown, the two magnetic sheet groups are respectively plugged into the skeleton groove from the left and right sides of the coil 200. It should be noted that the coil 200 includes a skeleton, a winding wire wound on the skeleton, and a pin 201 connected to the winding wire, wherein the skeleton is in the shape of a hollow rod or a cylinder, that is, the skeleton has a groove portion, which is called a skeleton groove in this embodiment, and one end of the magnetic sheet group can be plugged into the skeleton groove; the two magnetic sheet groups are installed in the skeleton groove, and then a gap sheet 302 is placed between the assembly surfaces 301 between the two magnetic sheet groups, and finally the two magnetic sheet groups are fixed to the coil 200 by the spring sheet 400 to ensure that the magnetic sheet groups do not move relative to the coil 200 in the subsequent assembly process, so as to ensure the stability and reliability of the subsequent assembly process. In this embodiment, the two magnetic sheet groups By fixing with the spring clip 400, there is no need for a magnetic shell to carry and fix the two magnetic sheet groups, thereby eliminating the process of assembling the magnetic sheet groups and the magnetic shell, saving the internal space of the confidentiality magnetic head, and improving the assembly efficiency and production cost of the confidentiality magnetic head; it should be noted that three coils 200 are welded on an FPC 500, and three magnetic sheet modules are correspondingly arranged. One magnetic sheet module includes two matching magnetic sheet groups 300, and the three magnetic sheet modules are correspondingly arranged on the three coils 200. Taking the magnetic sheet module on one of the coils 200 as an example, one magnetic sheet group 300 is inserted from one side of the coil 200, and the other magnetic sheet group 300 is inserted from the other side of the coil 200, and the two magnetic sheet groups 300 are fixed by the spring clip 400.

[0044] Inject conductive glue 800 into the shoulder of the magnetic sheet group 300, and use the conductive glue 800 to fix the assembly position between the shell 100 and the magnetic sheet group 300. Specifically, the conductive glue 800 is injected into the position between the shoulder of the magnetic sheet group 300 and the positioning groove 101. After the conductive glue 800 solidifies, the shell 100 and the magnetic sheet group 300 are fixedly connected, and electrical conduction between the magnetic sheet group 300 and the shell 100 is achieved. It should be noted that the groove width of the positioning groove 101 is greater than the width of the magnetic sheet group 300, so that the magnetic sheet group 300 can be accommodated in the positioning groove 101 and the magnetic sheet group 300 is prevented from shifting.

[0045] Install housing 100, refer to Figure 6As shown, the housing 100 is covered on the coil 200 and the magnetic sheet group 300, and the housing 100 and the magnetic sheet group 300 are bonded and fixed by a conductive adhesive 800. Specifically, the lower end of the housing 100 is open, and a notch 102 is opened at the upper end. The housing 100 is installed on the coil 200 and the magnetic sheet group 300 from top to bottom. At this time, the lower end surface of the housing 100 corresponds to the separation portion 601 between the FPC 500 and the puzzle board 600 and abuts against the avoidance groove 701 of the SMT carrier board 700. The depth of the avoidance groove 701 can be set according to actual needs, that is, by adjusting the avoidance groove 701, the depth of the avoidance groove 701 can be set according to actual needs. The depth of the groove 701 is used to control the dimension of the shell 100 being pressed in, and the magnetic sheet group 300 passes through the notch 102 on the upper end surface of the shell 100. After assembly, the coil 200, the magnetic sheet group 300 and the spring 400 are all accommodated in the shell 100 and do not contact the shell 100. In other embodiments, a positioning groove 101 is provided on the shell 100. When the shell 100 is installed, the positioning groove 101 is installed in alignment with the magnetic sheet group 300. The position of the magnetic sheet group 300 is limited by the positioning groove 101 to prevent the magnetic sheet group 300 from shifting in the shell 100.

[0046] Separate, separate the FPC500 assembled with the shell 100 from the puzzle board 600. Specifically, the FPC500 can be separated from the puzzle board 600 by wire cutting or laser cutting, and the inside of the shell 100 is sealed by injecting glue once through the two glue injection holes 602 on the FPC500, and waterproof tape is attached to the gold finger surface of the FPC500.

[0047] Arc surface grinding: the magnetic head and FPC500 are ground together.

[0048] Reference Figures 7 to 9A security magnetic head is shown, the security magnetic head comprises a housing 100, a coil 200, an FPC 500 and a magnetic sheet module, wherein the magnetic sheet module comprises two matching magnetic sheet groups 300, the FPC 500 has a plurality of pads 501, the coil 200 has a plurality of pins 201, the plurality of pins 201 can be in a planar bending shape or a vertical shape or a patch shape, the plurality of pins 201 are correspondingly welded on the plurality of pads 501 of the FPC 500, the two magnetic sheet groups 300 The two sides of the coil 200 are respectively plugged into the coil 200. In some other embodiments, the vertical pins 201 do not need to be bent, which has the advantages of reducing the cost of raw materials and facilitating the reduction of the size of the FPC500 pad 501. When the patch pins 201 are used, the pins 201 are flush with the bottom of the frame of the coil 200, and the frame of the coil 200 is close to the FPC500, which can reduce the height of the inside of the magnetic head. A gap sheet 302 is provided between the assembly surfaces 301 of the two magnetic sheet groups 300, and The two magnetic sheet groups 300 are fixedly connected by the spring sheet 400, so that the FPC 500, the coil 200 and the magnetic sheet group 300 are fixedly installed into an assembly component. After the conductive glue 800 is injected into the shoulder of the magnetic sheet group 300, the shell 100 cover is set on the assembly component, and the shell 100 and the magnetic sheet group 300 are bonded and fixed by the conductive glue 800; it should be noted that a positioning groove 101 is provided on the shell 100, and the shoulder of the magnetic sheet group 300 is accommodated in the positioning groove 101, so that the magnetic sheet group 300 is externally fixed. The outer shell 100 is positioned in the outer shell 100, and the conductive glue 800 is placed in the area between the shoulder of the magnetic sheet group 300 and the positioning groove 101 to prevent the conductive glue 800 from being squeezed and seeping out from the outer surface of the magnetic sheet group 300 after the outer shell 100 is installed. In this embodiment, the coil 200 is first welded to the FPC 500, and the magnetic sheet group 300 is fixed to the coil 200 by the spring 400, so that the outer shell 100 is installed on the magnetic sheet group 300 and the conductive glue 800 is injected once to achieve fixation, thereby improving production efficiency and reducing raw material costs.

[0049] In some embodiments, the positioning groove 101 is recessed from the inner wall of the shell 100. During installation, the shell 100 is installed on the assembly component from top to bottom. At this time, the bottom end of the shell 100 abuts against a horizontal plane, such as an SMT carrier 700. At this time, there is a certain gap between the shoulder of the magnetic sheet group 300 and the positioning groove 101 to avoid interference between the shell 100 and the magnetic sheet group 300 and displacement of the magnetic sheet group 300 during the assembly process. At the same time, the pressing method of the shell 100 can be controlled by adjusting the depth of the downward assembly of the shell 100, and the conductive glue 800 is used to fix the assembly component and the shell 100 and realize electrical conduction between the magnetic sheet group 300 and the shell 100.

[0050] In some embodiments, a notch 102 is provided on the shell 100, and the connection between the two magnetic sheet groups 300 protrudes from the notch 102. One end of the shell 100 is open to facilitate the cover to be placed on the assembly component, and the other opposite end of the shell 100 is provided with a plurality of through holes, which are the notches 102. When the shell 100 is placed on the assembly component, the top of the magnetic sheet group 300 protrudes from the notch 102 to avoid interference between the shell 100 and the magnetic sheet group 300. After the shell 100 is installed downward to the bottom abutment plane, the assembly component is accommodated in the shell 100 and the top of the magnetic sheet group 300 protrudes from the notch 102.

[0051] In some embodiments, the FPC500 is fixed on the puzzle board 600, and the coil 200 is welded and fixed to the FPC500. In this embodiment, for the convenience of assembly, several FPC500 can be arranged in an array on the puzzle board 600, and adjacent FPC500 can be arranged head to tail in an alternating manner to avoid interference between the coil 200, magnetic sheet group 300, spring sheet 400 and other components of two adjacent confidentiality heads during assembly. In addition, by utilizing the regular and stable arrangement of FPC500 on the puzzle board 600, the coil 200 can be welded to the pad 501 of the FPC500 by means of a patch, so that the magnetic sheet group 300 can be installed in the coil 200 without a magnetic shell, thereby reducing the number of components of the magnetic head and the volume of the magnetic head, and the space inside the shell 100; and the magnetic sheet group 300 can be plane-ground through a separate process, which does not affect the assembly process of the main production line, thereby improving the efficiency of the main production line.

[0052] There is a separation portion 601 between the FPC500 and the panel 600, and the separation portion 601 is used to avoid the shell 100, that is, the width of the separation portion 601 is greater than the wall thickness of the shell 100, so that when the shell 100 is installed later, the lower end of the shell 100 can pass through the separation portion 601 between the FPC500 and the panel 600. The panel 600 is placed on the SMT carrier 700, and the carrier is used to support the panel 600, and an avoidance groove 701 is arranged on the carrier, and the avoidance groove 701 is used to support the shell 100 and the groove depth of the avoidance groove 701 can be designed according to actual needs, so as to adjust the depth of the shell 100 to avoid direct contact with the inner wall magnetic sheet group 300 or the spring sheet 400 of the shell 100; in this embodiment, the FPC500 is used as the assembly reference, and the coil 200 is welded to the FPC500, which is convenient for automated operation and improves assembly efficiency.

[0053] In some embodiments, the spring clip 400 is inserted into the side between the two magnetic sheet groups 300 and accommodated in the outer shell 100. The function of the side spring clip 400 is only to fasten the two magnetic sheet groups 300 and it does not contact the outer shell 100. That is, the outer shell 100 and the internal parts do not need to contact through the spring clip 400 to meet the performance. The conductive glue 800 is set between the shoulder of the magnetic sheet group 300 and the positioning groove 101 of the outer shell 100 to fix and limit the assembly position of the internal parts such as the coil 200 and the magnetic sheet group 300.

[0054] In the present embodiment, three coils 200 are correspondingly welded on one FPC500, and three magnetic sheet modules are also correspondingly arranged, that is, one confidentiality magnetic head includes six magnetic sheet groups 300, and the six magnetic sheet groups 300 are correspondingly installed on the three coils 200 in pairs, and the assembly surface 301 between the two magnetic sheet groups 300 correspondingly assembled on the coil 200 is a ground plane, and a gap sheet 302 is arranged between the two assembly surfaces 301. There are three spring sheets 400 and they are correspondingly snapped into the two matching magnetic sheet groups 300. In the present embodiment, the coil 200 is firstly welded and fixed on the FPC500, and the two magnetic sheet groups 300 are correspondingly inserted into the coil 200 from both sides, and then the two magnetic sheet groups 300 are fixed by the spring sheets 400, and there is no need to fix the two magnetic sheet groups 300 by a magnetic shell, thereby reducing the number of components of the confidentiality magnetic head and reducing the volume of the magnetic head.

[0055] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for manufacturing a confidential magnetic head, It is characterized in that The steps include: Solder the FPC and solder the coil to the pad of the FPC; Install the magnetic sheet group, insert the two magnetic sheet groups into the skeleton slots from the left and right sides of the coil respectively; Inject conductive glue into the shoulders of the magnetic sheet group; Install the outer shell, and place the outer shell cover on the coil and the magnetic sheet group, and fix the outer shell and the magnetic sheet group by bonding with conductive glue; Separate the magnetic head and FPC from the panel.

2. A method for manufacturing a security magnetic head according to claim 1, It is characterized in that Before the step of assembling the magnetic sheet group, a grinding step is also included to grind the assembly surfaces of the magnetic sheets.

3. A method for manufacturing a security magnetic head according to claim 1, It is characterized in that The step of installing the magnetic disk group also includes the following steps: Install the gap sheet between the assembly surfaces of the two magnetic sheet groups; Install the spring sheet, and install the spring sheet on the two magnetic sheet groups to fix the two magnetic sheet groups and the gap sheet.

4. A method for manufacturing a security magnetic head according to claim 3, It is characterized in that The three spring sheets are sequentially clipped onto the two matching magnetic sheet groups.

5. The method for manufacturing a security magnetic head according to claim 1, It is characterized in that Before the FPC welding step, a pre-step is also included: using an SMT carrier board to carry the panel, several FPCs are arranged in an array on the panel, and two adjacent FPCs are arranged head to tail in an alternating manner.

6. A method for manufacturing a security magnetic head according to claim 5, It is characterized in that In the step of installing the outer shell, the lower end of the outer shell passes through the separation portion of the panel and abuts against the avoidance groove of the SMT carrier board.

7. A method for manufacturing a security magnetic head according to claim 6, It is characterized in that In the step of installing the outer shell, the shoulder of the magnetic sheet group is accommodated in the positioning groove inside the outer shell.

8. A method for manufacturing a security magnetic head according to claim 1, It is characterized in that In the step of welding the FPC, there are several welding pads on the FPC, and several pins on a coil are correspondingly welded to several welding pads of one FPC.

9. A confidential magnetic head, It is characterized in that The security magnetic head is manufactured by the manufacturing method of the security magnetic head according to any one of claims 1 to 8, and the security magnetic head comprises: shell; An FPC, having at least two coils welded thereto, and the coils are accommodated in the housing; A magnetic sheet module is arranged on the coil correspondingly, and includes two matching magnetic sheet groups, and the two magnetic sheet groups are respectively inserted into the coil from both sides of the coil; Wherein, a gap sheet is arranged between the two magnetic sheet groups, and the two magnetic sheet groups are fixedly connected by a spring sheet.

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