JP2007324469A - Substrate mounting method, and method of manufacturing electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To mount a shield case on a substrate in detachable manner, and actualize the mounting with reduced man-hours. <P>SOLUTION: A shield member 13 which is so mounted on a substrate 10 as to cover an electronic component 11 on the substrate 10 for shielding electromagnetic waves of the electronic component, is mounted on the substrate 10 through a fixing component 12 that holds the shield member 13. Here, after the electronic component 11 and the fixing component 12 are mounted at a specified position on the substrate 10, a clip part 12b provided to the fixing component 12 is made to hold the shield member 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate mounting method for mounting a shield member on a substrate included in an electronic device, and an electronic device manufacturing method to which the mounting method is applied.

  Conventionally, in order to block electromagnetic waves of an electronic component mounted on a substrate, a metal shield case is mounted on the substrate so as to cover the electronic component. As a method for mounting the shield case on the substrate, a method in which a shield holding frame for supporting the shield case is previously mounted on the substrate and the shield case is fitted on the shield holding frame is generally well known. However, since the shield holding frame has an inverted L-shape when viewed in cross section, when viewed from directly above when mounted on the substrate, a portion that is behind the shield holding frame is formed. . That is, when an electronic component is mounted on that portion, the electronic component placed at that position is not captured during camera inspection, and thus there is a problem that the electronic component cannot be placed in a portion behind the shield holding frame.

  The shield case is placed on the shield holding frame and then mounted on the board by soldering. However, since the part to be connected by solder covers a wide area, it is connected by factors such as board warpage and deformation of the shield case. There is also a problem that a defect is likely to occur, and the shielding effect is halved when a connection failure occurs.

  In order to solve these problems, a technique is adopted in which a small fixed component such as a clip is mounted on the substrate instead of the shield holding frame, and the side surface of the shield case is inserted into the clip to be mounted on the substrate.

Patent Document 1 discloses disclosure of shielding an electronic component using a shield case, and Patent Document 2 discloses disclosure of mounting the shield case via a small fixed component. .
JP 2004-111627 A JP 2005-332953 A

  By the way, in the method of mounting the shield case on the board using the shield holding frame, since the shield case itself is connected to the board with solder, the shield case cannot be attached and detached after mounting. There has been a problem that it becomes impossible to perform camera inspection of electronic components mounted on the board or replacement of electronic components during maintenance.

  Further, when the shield case is mounted using a small solid component, there is a problem that a process of mounting the solid component on the substrate newly occurs, and the man-hour as a whole increases.

  The present invention has been made in view of this point, and an object of the present invention is to mount a shield case on a substrate in a detachable state and realize the mounting with as few man-hours as possible.

  The present invention provides a fixing component for fixing a shielding member when a shielding member for shielding an electronic component on a substrate is mounted on the substrate, and the electronic component and the fixing component are simultaneously placed at predetermined positions on the substrate. The shield member is mounted and held by the shield member holding portion provided in the fixed component.

  By doing in this way, since an electronic component and the fixed component for holding a shield member can be simultaneously mounted on a board | substrate, it becomes unnecessary to newly increase the procedure for fixed component mounting.

  According to the present invention, it is not necessary to increase the procedure for mounting the shield member to the fixed component, which leads to shortening of the procedure for mounting the shield member.

  In this case, by holding the shield member in a removable state with respect to the fixed component, it becomes possible to easily remove the shield member even after mounting on the board, and the arrangement state of the electronic parts hidden by the shield member Can be easily inspected with a camera, and the electronic components on the board can be exchanged.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
This example is applied to an example in which a shield case as a shield member used for electromagnetic wave shielding is mounted on a circuit board disposed in an electronic device. Here, an example in which the electronic device is applied to a mobile phone terminal is described. FIG. 1 is a diagram illustrating an example of a state in which an electronic component, a fixed component for holding a shield case, and a shield case are mounted on a substrate. 1A is shown as a side cross-sectional view, and FIG. 1B is a cross-sectional view taken along the line II of FIG. 1A.

  The substrate 10 disposed in the electronic device is a printed circuit board provided with wiring for electronic circuits and wiring for ground conduction, and the electronic component 11 is disposed on the surface of the substrate 10. The electronic component 11 is an IC chip or a passive component. A shield case 13 is attached to the surface of the substrate 10 in this example to block electromagnetic waves from the electronic component 11. The shield case 13 is configured to be held using the fixed component 12. The fixed component 12 has a flat surface portion 12 a for connecting to the substrate 10 on the bottom surface, and the flat surface portion 12 a is electrically connected to a ground pattern on the substrate 10. The configuration in which the shield case 13 is held by the fixed component 12 is a configuration in which the side surface 13a of the shield case 13 is held between the clip portions 12b. The shield case 13 is composed of a metal plate, and is shielded from electromagnetic waves of the electronic component 11 by being mounted on the substrate 10 so as to cover the electronic component 11. As shown in FIG. 1B, a plurality of fixing parts 12 are provided for one side of the shield case 13. It is assumed that the number of the fixed parts 12 can be appropriately changed according to the size of the shield case.

  Next, a procedure for mounting each component on the substrate 10 will be described with reference to the flowchart of FIG. First, the cream solder 14 is applied to the place on the substrate 10 where the electronic component 11 and the fixed component 12 are mounted (step S11). A place where the electronic component 11 is mounted is a conductive portion connected to a circuit pattern to which the mounted electronic component 11 is connected. Next, the electronic component 11 and the fixed component 12 are placed on the place where the cream solder 14 is applied and temporarily arranged (step S12). Next, reflow heating is performed to form a solder connection state (step S13). After the solder connection state is formed, the shield case 13 is fitted into the place where the fixed component 12 is mounted (step S14).

  FIG. 3 is an explanatory diagram corresponding to each step of the flowchart of FIG. FIG. 3A shows a state in which the cream solder 14 is applied to the substrate 10 and corresponds to step S11 in FIG. FIG. 3B shows a state in which the electronic component 11 and the fixed component 12 are arranged on the substrate 10 where the cream solder 14 is applied, and corresponds to step S12 in FIG. FIG. 3C shows a state in which each side of the shield case 13 is inserted into each fixed component 12 after the solder connection state is formed, and corresponds to step S14 in FIG. FIG. 3D shows a state in which the shield case 13 is mounted on the substrate 10 while being sandwiched between the fixed components 12.

  In this way, when mounting the electronic component on the substrate, the fixed component of the shield case is mounted at the same time, so that the overall mounting procedure does not increase, and the shield case can be mounted on the substrate with less man-hours. .

  In this case, since the shield case is sandwiched and held between the fixed parts, it can be freely attached and detached. Therefore, even after the shield case is attached, by removing the shield case from the substrate, it becomes possible to easily inspect fixed parts in the shield case by camera photography and repair / replace electronic parts.

  In addition, if the shield case is in contact with any part of the fixed part, the shield case and the board are electrically connected. Therefore, even if the board or the shield case is warped, poor connection may occur. It becomes difficult. Therefore, the shielding effect of the shielding case is also improved.

  In the above-described embodiment, the fixing part is used for holding the shield case. However, as shown in FIG. 4, as the holding member of the shield case 13, the shield holding frame 15 and the fixing part 12 are used. May be used in combination. FIG. 4A is a side sectional view, and FIG. 4B is a sectional view taken along the line II-II in FIG. 4A. 4A and 4B show a state in which the electronic components 11a and 11b are mounted on the substrate 10, and the shield case 15 is mounted on the substrate 10 so as to be held by the shield holding frame 13. FIG. A shield plate 13 ′ is provided as a partition between the electronic components 11 a and 11 b, and the shield plate 13 ′ is held by the fixed component 12. For example, as shown in FIG. 5, if the shield holding frame 15 is used for the outer frame and the fixing component 12 is used for the portion to be finely divided, the shield plate 13 'can be disposed relatively freely. And the degree of design freedom is improved. It is also possible to provide an appropriate shield to an appropriate location.

  In the embodiment described so far, the example in which the electronic component 11 is simultaneously mounted on the substrate 10 at the time of the work of mounting the fixed component 12 on the substrate 10 has been described. 12 may be mounted on the substrate 10 in a connected state. The mounting procedure in this case will be described with reference to the flowchart of FIG.

  First, the cream solder 14 is applied to the place on the substrate 10 where the electronic component 11 and the fixed component 12 are mounted (step S21). A place where the electronic component 11 is mounted is a conductive portion connected to a circuit pattern to which the mounted electronic component 11 is connected. Next, the electronic component 11 is placed and provisionally arranged at the location where the cream solder 14 is applied (step S22). Next, the clip 12b of the fixed component 12 is sandwiched at a predetermined position on the side surface 13a of the shield case 13, and the fixed component 12 is attached to the shield case 13 (step S23). Next, the shield case 13 to which the fixed component 12 is attached is temporarily placed on the substrate 10 (step S24), and finally, reflow heating is performed to form a solder connection state (step S25).

  FIG. 7 is an explanatory diagram corresponding to each step of the flowchart of FIG. FIG. 7A shows a state in which the cream solder 14 is applied to the substrate 10 and corresponds to step S21 in FIG. FIG. 7B shows a state in which the electronic parts 11 and the electronic component 11 are arranged on the substrate 10 where the cream solder 14 is applied, and corresponds to step S22 in FIG. FIG. 7C shows a state in which the fixed component 12 is attached to each side of the shield case 13, and corresponds to step S23 in FIG. The fixing component 12 is attached to the shield case 13 by sandwiching the side surface 13a of the shield case 13 between the clip portions 12b of the fixing component 12. FIG. 7D shows a state in which the shield case 13 to which the fixing component 12 is attached is mounted on the substrate 10, and the flat portion 12 a of the fixing component 12 is electrically connected to the ground pattern on the substrate 10. Connected.

  In this way, by connecting the fixed component to the shield case in advance and then mounting the fixed component on the substrate, the shield case and the fixed component can be reliably connected. In the case where the fixed components are individually mounted on the substrate, the shield case may not be attached if the individual fixed components are connected in a shifted state, but this method can solve the problem.

  In the above-described embodiment, an example in which the shield case 13 is used as a member that blocks electromagnetic waves of the electronic component 11 has been described. However, as shown in FIG. 8, a copper foil is stretched over the entire back surface. The flexible substrate 16 having a shielding effect may be used as a shielding material by being connected to the fixed component 12 instead of the shielding case 13. In this case, if any side of the flexible board 16 is connected to the connector 17 or the like to function as a circuit board and the electronic component 11 or the like is mounted on the circuit surface, the limited space can be effectively used. .

They are the side view (a) which shows the example of arrangement | positioning of the shield case by one embodiment of this invention, and sectional drawing (b) which follows the II line | wire of a side view. It is a flowchart explaining the example of the mounting procedure to the board | substrate by one embodiment of this invention. It is a perspective view which shows the state of each step | level of mounting to the board | substrate by one embodiment of this invention. It is side view (a) which shows the example of arrangement | positioning of the shield case by the modification of embodiment of this invention, and sectional drawing (b) which follows the II-II line of a side view. It is upper surface sectional drawing which shows the example of arrangement | positioning of the shield board by the modification of embodiment of this invention. It is a flowchart explaining the example of the mounting procedure to the board | substrate by the modification of embodiment of this invention. It is a perspective view which shows the state of each step | level of mounting to the board | substrate by the modification of embodiment of this invention. It is side surface sectional drawing which shows the example of arrangement | positioning of the shield case by the modification of embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Board | substrate, 11 ... Electronic component, 12 ... Fixed component, 12a ... Plane part, 12b ... Clip part, 13 ... Shield case, 13 '... Shield plate, 14 ... Cream solder, 15 ... Shield holding frame, 16 ... Flexible substrate , 17 ... Connector

Claims (6)

In a board mounting method for mounting a shield member for shielding electronic components on a board on the board,
A step of simultaneously mounting the electronic component and a fixing component for fixing the shield member at a predetermined position on the substrate;
And a step of holding the shield member in the shield member holding portion provided in the fixed component. The substrate mounting method according to claim 1,
The step of simultaneously mounting the electronic component and the fixed component on the substrate is a step of applying solder to the electronic component and the fixed component, and mounting on the substrate with the applied solder. Implementation method. The substrate mounting method according to claim 1,
The substrate mounting method, wherein the shield member is held in a detachable state with respect to the fixed component. In a board mounting method for mounting a shield member for shielding electronic components on a board on the board,
Attaching a fixing part for fixing the shield member to a predetermined position of the shield member;
Mounting the fixed component on which the shield member is mounted at a predetermined position on the substrate while the shield member is mounted. The board mounting method according to claim 4,
The substrate mounting method, wherein the fixed component is attached to the shield member in a detachable state. In the manufacturing method of electronic equipment,
When a shield member that shields an electronic component on a board built in the electronic device is mounted on the board,
A step of simultaneously mounting the electronic component and a fixing component for fixing the shield member at a predetermined position on the substrate;
And a step of holding the shield member in a shield member holding portion provided in the fixed component.

Images