JP2020120155A - Ground structure - Google Patents

Abstract

To provide a ground structure capable of taking measures against noise even when a resin housing is used.SOLUTION: A ground structure 32 includes: a plurality of substrates 24, disposed inside a housing 20, spaced apart from each other, and extending in a predetermined direction; and a rod-shaped conductor 34, penetrating through each of the substrates 24, and connected to a frame ground 16 provided on a back surface 14 of a panel 12, for example, as an external ground for the housing 20. Each of the substrates 24 has a through-hole H through which the rod-shaped conductor 34 passes and a ground pattern GP connected to the rod-shaped conductor 34 through the through-hole H.SELECTED DRAWING: Figure 1

Description

The present invention relates to a ground structure for grounding an electronic device having a resin housing.

Some electronic devices include a housing into which a substrate can be inserted and removed as necessary.

JP, 10-178290, A

In the above electronic device, noise countermeasures may be taken by connecting the substrate to the frame ground of the electronic device. However, when the housing of the electronic device is made of resin, it becomes difficult to connect the substrate to the frame ground.

Therefore, an object of the present invention is to provide a grounding structure that can take measures against noise even if a resin case is used.

The present invention is a grounding structure for grounding an electronic device having a resin case, wherein the plurality of boards are arranged inside the case and extend in a predetermined direction with a space between each other and a plurality of the boards. And a rod-shaped conductor that is connected to the ground outside the housing, and each of the plurality of substrates includes a through-hole through which the rod-shaped conductor passes, and a rod-shaped conductor that passes through the through-hole. It has a connected ground pattern.

According to the present invention, external noise and the like can be guided to the ground through the rod-shaped conductor that is connected to the ground pattern of each substrate, and as a result, noise countermeasures can be taken even if a resin housing is used.

FIG. 3 is a perspective view showing the configuration of the electronic device according to the first embodiment. It is the figure which looked at the electronic device from the lower surface side of FIG. It is a perspective view which shows the structure of the electronic device in 2nd Embodiment. FIG. 8 is a diagram showing a rod-shaped conductor of Modification 1. It is a figure which shows the rod-shaped conductor of the modification 2.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail with reference to the accompanying drawings, by way of preferred embodiments.

[Embodiment]
(First embodiment)
FIG. 1 is a perspective view showing a configuration of an electronic device 10 according to the first embodiment, and FIG. 2 is a view of the electronic device 10 seen from the lower surface side of FIG. The electronic device 10 is a numerical controller that controls an industrial machine such as a robot, an injection molding machine, a machine tool that uses a tool or an electric discharge to machine an object to be machined, and is provided on the back surface 14 side of the panel 12.

The panel 12 is a liquid crystal panel in the present embodiment. A display screen (not shown) is provided on the surface opposite to the back surface 14 of the panel 12, and a frame ground 16 is provided on the back surface 14 of the panel 12. In the following description, the up/down, left/right, and front/back directions will be described according to the direction of the display screen of the panel 12 viewed from the front.

The electronic device 10 includes a resin housing 20 attached to the upper side of a frame ground 16 provided on the back surface 14 of the panel 12, a backboard 22, and a plurality of substrates 24. In order to make the inside of the case 20 easier to see, the case 20 is shown by a chain double-dashed line in FIG. 1, and the case 20 is omitted in FIG.

The backboard 22 is connected to the panel 12. The backboard 22 is erected from the rear surface 14 of the panel 12 toward the inside of the housing 20. It is preferable that the panel 12 is erected in a direction orthogonal to the back surface 14 of the panel 12. On the mounting surface 22a of the backboard 22, a plurality of board-side connectors 26 for connecting the board 24 are provided.

The plurality of substrates 24 include a substrate as a control unit that controls the industrial machine and a substrate as a display control unit that controls the panel 12 (liquid crystal panel). Each of the plurality of boards 24 has a board-side connector 28 connected to any of the plurality of board-side connectors 26. The board-side connector 28 is mounted on the end of the mounting surface of the board 24 facing the backboard 22.

At least one of the plurality of boards 24 has an interface connector 30. The interface connector 30 is a connector for connecting to an external device, and is mounted on the mounting surface of the board 24 at the end opposite to the end facing the backboard 22. When the board-side connector 26 of the backboard 22 and the board-side connector 28 of the board 24 are connected, the interface connector 30 is exposed on the surface (lower surface) of the housing 20 opposite to the backboard 22.

The plurality of substrates 24 are arranged inside the housing 20 at intervals in the front-rear direction and extend in the up-down direction. The front-back direction is a direction orthogonal to the back surface 14 of the panel 12, and the up-down direction is a direction along the back surface 14 of the panel 12 (direction parallel to the back surface 14). It should be noted that some of the plurality of substrates 24 may be arranged at intervals in the left-right direction, as illustrated in FIGS. The left-right direction is a direction orthogonal to the back surface 14 of the panel 12 and a direction orthogonal to the direction parallel to the back surface 14.

Each of the plurality of substrates 24 has a ground pattern GP and a through hole H (see FIG. 2) penetrating the ground pattern GP and the substrate 24. In the present embodiment, it is assumed that the ground pattern GP is provided on the mounting surface of the end of the substrate 24 on the opposite side (lower side) to the side (upper side) facing the backboard 22.

The ground pattern GP may be provided at a site other than the lower end of the substrate 24. The ground pattern GP may be provided on the surface of the substrate 24 opposite to the mounting surface, or may be provided between the surface and the mounting surface.

Next, the ground structure 32 for grounding the electronic device 10 will be described. The ground structure 32 includes the plurality of substrates 24 and the rod-shaped conductor 34. The rod-shaped conductor 34 is a rod-shaped conductor that penetrates each of the plurality of substrates 24 and the housing 20.

The rod-shaped conductor 34 is one member that is not separated from one end to the other end, and is inserted into each through hole H of the plurality of substrates 24. One end of the rod-shaped conductor 34 is connected to the frame ground 16 provided on the back surface 14 of the panel 12. The rod-shaped conductor 34 and the frame ground 16 may be fixed.

In addition, when a part of the plurality of substrates 24 is arranged with a space in the left-right direction, the rod-shaped conductor 34 is provided for each of the plurality of substrates 24 arranged in the left-right direction as illustrated in FIGS. 1 and 2. Is penetrated. That is, one or a plurality of rod-shaped conductors 34 penetrate all of the plurality of substrates 24 arranged inside the casing 20, and the rod-shaped conductors 34 are connected to the frame ground 16.

As described above, in the ground structure 32 of the present embodiment, each ground pattern GP of the plurality of substrates 24 is connected to the rod-shaped conductor 34 penetrating each of the substrates 24, and the rod-shaped conductor 34 covers the resin casing 20. It penetrates and is connected to the frame ground 16 on the back surface 14 of the panel 12. As a result, external noise or the like to the electronic device 10 can be guided to the frame ground 16 of the panel 12, and as a result, noise countermeasures can be taken even if the resin case 20 is used.

In the electronic device 10 of the present embodiment, the ground pattern GP is provided on the end side of the board 24 on which the interface connector 30 is mounted. As a result, it is possible to suppress the influence of electrostatic discharge generated when the cable is inserted into or removed from the interface connector 30.

(Second embodiment)
FIG. 3 is a perspective view showing the configuration of the electronic device 10 according to the second embodiment. The same components as those described in the first embodiment will be designated by the same reference numerals, and overlapping description will be omitted.

The electronic device 10 of the present embodiment is different from that of the first embodiment in that it is not provided on the back surface 14 side of the panel 12. The electronic device 10 of the present embodiment is attached to a predetermined location of a machine tool.

The ground structure 32 of the present embodiment includes a plurality of substrates 24 and a rod-shaped conductor 34 that penetrates each of the plurality of substrates 24, as in the first embodiment. The rod-shaped conductor 34 of the present embodiment is different from the first embodiment in which the rod-shaped conductor 34 penetrates the casing 20 in that it does not penetrate the casing 20.

Further, the earth structure 32 of the present embodiment additionally includes a cable 40 that connects the ground outside the housing 20 and the rod-shaped conductor 34. The ground may be, for example, a frame ground such as a metal base on which the machine tool is mounted, or an earth ground.

In the ground structure 32 of the present embodiment, each ground pattern GP of the plurality of substrates 24 is connected to the rod-shaped conductor 34 penetrating each of the substrates 24, and the casing 40 is connected via the cable 40 connected to the rod-shaped conductor 34. It is connected to the ground outside the body 20. As a result, external noise or the like to the electronic device 10 can be guided to the ground outside the housing 20. As a result, noise countermeasures can be taken even if the resin housing 20 is used, as in the first embodiment. Can be given.

In addition, when a part of the plurality of substrates 24 is arranged in the left-right direction with a space therebetween, the rod-shaped conductor 34 is penetrated through each of the plurality of substrates 24 arranged in the left-right direction as illustrated in FIG. 3. .. That is, one or a plurality of rod-shaped conductors 34 penetrate all of the plurality of substrates 24 arranged inside the housing 20, and the plurality of substrates 24 are connected via the cables 40 connected to the respective rod-shaped conductors 34. Each ground pattern GP is connected to the ground outside the housing 20.

[Modification]
Although the embodiment has been described as an example of the present invention, it is needless to say that various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

(Modification 1)
FIG. 4 shows a rod-shaped conductor 34 of the first modification. The rod-shaped conductor 34 of Modification 1 is formed in a spiral shape. As a result, even if the relative positions of the through holes H of each of the plurality of substrates 24 deviate in the plane direction of the substrate 24, the rod-shaped conductor 34 deforms, and the through holes H of which the relative positions deviate are inserted. Easier to do.

(Modification 2)
FIG. 5 shows a rod-shaped conductor 34 of Modification 2. The rod-shaped conductor 34 of Modification 2 is configured to be separable. That is, the rod-shaped conductor 34 has a magnetic body 34A fixed to the through hole H of each of the plurality of substrates 24, and a plurality of rod-shaped portions 34B provided between the adjacent substrates 24. The rod-shaped portion 34B is formed by rod-shaped iron or the like that can be connected to the magnetic body 34A.

One end of the rod-shaped portion 34B is connected to the magnetic body 34A fixed to one through hole H of the adjacent substrate 24, and the rod-shaped portion 34A is fixed to the magnetic body 34A fixed to the other through hole H of the adjacent substrate 24. The other end of the portion 34B is connected.

In the rod-shaped conductor 34 of the modified example 2, the rod-shaped portion 34B can be displaced and connected to the magnetic body 34A. Therefore, even if the relative positions of the through holes H of each of the plurality of substrates 24 deviate in the plane direction of the substrate 24, by shifting the connection position of the rod-shaped portion 34B to the magnetic body 34A, the through holes whose relative positions deviate. It becomes easy to insert into each of H.

(Modification 3)
The other end of the back surface 14 of the panel 12 opposite to the one end of the rod-shaped conductor 34 connected to the frame ground 16 may be in contact with the housing 20. As a result, the rod-shaped conductor 34 can have the function of reinforcing the housing 20 in addition to the function of guiding external noise to the frame ground 16.

[Invention Obtained from Embodiment]
The invention which can be understood from the above-described embodiment will be described below.

The present invention is a ground structure (32) for grounding an electronic device (10) having a resin housing (20). The ground structure (32) is disposed inside the housing (20), and penetrates each of the plurality of substrates (24) and the plurality of substrates (24) which are spaced from each other and extend in a predetermined direction, and the housing is provided. A rod-shaped conductor (34) connected to the ground outside the body (20). Each of the plurality of substrates (24) has a through hole (H) through which the rod-shaped conductor (34) passes, and a ground pattern (GP) connected to the rod-shaped conductor (34) passing through the through-hole (H).

As a result, external noise or the like can be guided to the ground through the rod-shaped conductor (34) connected to the ground pattern (GP) of each substrate (24), and as a result, even if the resin casing (20) is used, the noise can be introduced. Measures can be taken.

The rod-shaped conductor (34) may be a non-separable member from one end to the other end. Thereby, the rod-shaped conductor (34) can be made stronger than in the case where the rod-shaped conductor (34) is separable.

The rod-shaped conductor (34) may be formed in a spiral shape. Thereby, the relative position of each through hole (H) of the plurality of substrates (24) arranged in the direction orthogonal to the back surface (14) of the panel (12) is in the plane direction of the substrate (24). Even if they are displaced, the rod-shaped conductor (34) is deformed, so that the rod-shaped conductors (34) are easily inserted into the through holes (H) whose relative positions are displaced.

The rod-shaped conductor (34) is provided between the magnetic body (34A) fixed to the through hole (H) and the magnetic body (34A) fixed to the through hole (H) of the adjacent substrate (24), You may have several rod-shaped part (34B) connected with a magnetic body (34A). As a result, the rod-shaped portion (34B) can be displaced and connected to the magnetic body (34A). Therefore, even if the relative position of each through hole (H) of the plurality of substrates (24) shifts in the surface direction of the substrate (24), the connection position of the rod-shaped portion (34B) to the magnetic body (34A) is displaced. This facilitates insertion into each of the through holes (H) whose relative positions are displaced.

The ground structure (32) may include a cable (40) connecting the rod-shaped conductor (34) and the ground. Thereby, the noise arriving at the housing (20) can be guided from the rod-shaped conductor (34) through the cable (40) to the ground outside the housing (20).

The electronic device (10) is arranged on the frame ground (16) of the back surface (14) of the panel (12), and the plurality of substrates (24) are arranged in a direction orthogonal to the back surface (14) of the panel (12). The rod-shaped conductors (34) may extend in the direction along the back surface (14) with a space therebetween and may be connected to the frame ground (16) through the housing (20). As a result, noise that reaches the housing (20) can be guided from the rod-shaped conductor (34) to the frame ground (16) outside the housing (20).

The electronic device (10) is connected to the back surface (14) side of the panel (12) and is erected toward the inside of the housing (20), and a plurality of substrates (24) are provided inside the housing (20). A backboard (22) to be connected, at least one of the plurality of boards (24) has an interface connector (30) mounted at an end opposite to the backboard (22), and has a ground pattern. (GP) may be provided at each end of the plurality of substrates (24). As a result, it is possible to suppress the influence of electrostatic discharge generated when the cable (40) is inserted into or removed from the interface connector (30).

DESCRIPTION OF SYMBOLS 10... Electronic equipment 12... Panel 16... Frame ground 20... Housing 22... Backboard 24... Board 26... Board side connector 28... Board side connector 30... Interface connector 32... Ground structure 34... Rod-shaped conductor 34A... Magnetic body 34B... Rod 40... Cable

Claims (7)

A ground structure for grounding an electronic device having a resin casing,
A plurality of substrates that are arranged inside the housing and that extend in a predetermined direction with a space between each other;
A rod-shaped conductor that penetrates each of the plurality of substrates and is connected to a ground outside the housing,
Equipped with
An earth structure in which each of the plurality of substrates has a through hole through which the rod-shaped conductor passes and a ground pattern connected to the rod-shaped conductor passing through the through-hole. The ground structure according to claim 1,
The ground structure, wherein the rod-shaped conductor is a non-separable member from one end to the other end. The ground structure according to claim 2,
The rod-shaped conductor is a ground structure formed in a spiral shape. The ground structure according to claim 1,
The rod-shaped conductor has a magnetic body fixed to the through hole and a plurality of rod-shaped portions provided between the magnetic bodies fixed to the through holes of the adjacent substrates and connected to the magnetic body. , Earth structure. The ground structure according to any one of claims 1 to 4,
An earth structure, comprising a cable connecting the rod-shaped conductor and the ground. The ground structure according to any one of claims 1 to 4,
The electronic device is arranged on the frame ground on the back surface of the panel,
A plurality of the substrates, extending in a direction along the back surface at intervals in a direction orthogonal to the back surface of the panel,
An earth structure in which the rod-shaped conductor penetrates the housing and is connected to the frame ground. The ground structure according to claim 6,
The electronic device includes a backboard connected to the back surface side of the panel, erected toward the inside of the housing, and having a plurality of the substrates connected inside the housing.
At least one of the plurality of boards has an interface connector mounted at an end opposite to the backboard,
The ground structure is provided on the end of each of the plurality of substrates.

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