Electronic device

Abstract

To provide an electronic device capable of suppressing cavity resonance.SOLUTION: An electronic device comprises a metal housing 20, a connector 50 having a shield shell 53, and a grounding member 60. The grounding member 60 is disposed in a gap 70 between the metal housing 20 and the shield shell 53 so as to ground the shield shell 53 to the metal housing 20. The gap 70 includes: a first waveguide part 71 which comprises a top wall 23 and a side wall of the metal housing 20, and the shield shell 53; and a second waveguide part 72, continuous with a rear end of the first waveguide part 71, which comprises a rear wall 25 and the shield shell 53. The grounding member 60 is disposed in a region within a predetermined range from the rear end of the first waveguide part 71.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] TECHNICAL FIELD The disclosure herein relates to electronic devices. [Background technology]

[0002] Patent Document 1 discloses a shielded electrical connector. The contents of the prior art document are incorporated by reference as explanations of the technical elements in this specification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-178839 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, a connector having a shield shell is housed in a metal housing so that it can be connected to an external connector through an opening in the metal housing.

[0005] In a configuration in which a metal housing has a top wall, side walls, and rear wall that face the shielding shell and define a connector-receiving space that is connected to the opening, a gap occurs between the shielding shell and the metal housing during assembly. As EMC requirements increase in frequency, a new issue has emerged in which the gap functions as a waveguide, causing cavity resonance of electromagnetic noise. Further improvements are required in electronic devices in terms of the above and other aspects not mentioned.

[0006] One of the objects of the present disclosure is to provide an electronic device capable of suppressing cavity resonance. [Means for solving the problem]

[0007] An electronic device according to one aspect of the disclosure includes: a metal housing (20) having an opening (21) and providing a ground potential; a connector (50, 50A) having terminals (51), a housing (52) for accommodating the terminals, and a shield shell (53) for covering at least a portion of the housing, the connector (50, 50A) being disposed in a metal casing so as to be connectable to an external connector through an opening; a grounding member (60) disposed in a gap (70) between the metal housing and the shield shell for grounding the shield shell to the metal housing; Equipped with The metal housing faces the shield shell and has a top wall (23), side walls (24), and a rear wall (25) as wall portions defining a connector accommodating space (22) that communicates with the opening, the gap includes a first waveguide portion (71) including a top wall, a side wall, and a shield shell, and a second waveguide portion (72) connected to the rear end of the first waveguide portion and including a rear wall and a shield shell; The ground member is disposed in an area within a predetermined range from at least one of the front end and rear end, which are the ends on the opening side of the first waveguide portion.

[0008] In the gap between the shielding shell and the metal housing, a cavity resonance occurs with an antinode of the electric field at the end of the first waveguide section. According to the disclosed electronic device, a grounding member is provided in a predetermined area from the end of the first waveguide section. In other words, the shielding shell is grounded to the metal housing at or near the antinode of the electric field. This changes the mode of the resonant circuit and suppresses the cavity resonance.

[0009] The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The reference numerals in parentheses in the claims are intended to exemplarily indicate the corresponding parts of the embodiments described below, and are not intended to limit the technical scope. The objectives, features, and advantages disclosed in this specification will become more apparent by reference to the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a plan view showing an electronic device according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. [Figure 4] 10A and 10B are diagrams showing a waveguide section formed in a gap between a metal housing and a shield shell. [Figure 5] FIG. 10 is a diagram showing the electric field intensity distribution in a reference example. [Figure 6] 5A and 5B are diagrams illustrating the electric field intensity distribution in the electronic device according to the first embodiment. [Figure 7] FIG. 10 is a diagram illustrating the effect of cavity resonance suppression. [Figure 8] FIG. [Figure 9] FIG. 10 is a cross-sectional view showing an electronic device according to a second embodiment. [Figure 10] FIG. [Figure 11] 10A and 10B are diagrams illustrating the positional relationship between a waveguide section and a ground member. [Figure 12] FIG. 10 is a diagram illustrating the effect of cavity resonance suppression. [Figure 13] FIG. 11 is a perspective view showing the periphery of a connector in an electronic device according to a third embodiment. [Figure 14] 10A and 10B are diagrams showing a waveguide section formed in a gap between a metal housing and a shield shell. [Figure 15] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, several embodiments will be described with reference to the drawings. Note that in each embodiment, corresponding components are designated by the same reference numerals, and redundant description may be omitted. When only a portion of the configuration is described in each embodiment, the configuration of another embodiment previously described may be applied to the remaining portion of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of several embodiments may be partially combined together even if not explicitly stated, provided that there is no particular problem with the combination.

[0012] (First embodiment) The electronic device described in this embodiment is applicable to, for example, a mobile body. Examples of the mobile body include electric vehicles such as battery electric vehicles (BEV) and hybrid electric vehicles (HEV), vehicles equipped with internal combustion engines, flying bodies such as drones and electric vertical take-off and landing aircraft (eVTOL), ships, construction machinery, agricultural machinery, etc. BEV is an abbreviation for Battery Electric Vehicle. HEV is an abbreviation for Hybrid Electric Vehicle. eVTOL is an abbreviation for electronic Vertical Take-Off and Landing aircraft. An example in which the electronic device is applied to a vehicle will be described below. Note that the electronic device may also be applied to applications other than mobile bodies.

[0013] <Electronic equipment> First, a schematic configuration of an electronic device will be described with reference to Figs. 1 to 3. Fig. 1 shows an example of an electronic device. Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. Fig. 2 shows only some of the wiring elements of a printed circuit board. Also, Fig. 2 shows a simplified view of the structures of the connector terminals, photoelectric conversion unit, and the like. Fig. 3 is an enlarged perspective view of the periphery of the connector shown in Fig. 2. Fig. 3 shows a simplified view of the connector. Also, Fig. 3 shows only the elements of the metal housing that define one connector accommodating space.

[0014] In the following, the height direction of the electronic device is referred to as the Z direction. The direction perpendicular to the Z direction is referred to as the X direction. The direction perpendicular to both the X direction and the Z direction is referred to as the Y direction. The X direction, Y direction, and Z direction are in a mutually perpendicular positional relationship.

[0015] As shown in FIGS. 1 to 3, the electronic device 10 includes a metal housing 20, a printed circuit board 30, electronic components 40, a connector 50, a photoelectric conversion unit 55, and a grounding member 60.

[0016] The metal housing 20 houses other elements that make up the electronic device 10. The metal housing 20 is made of a metal material suitable for electromagnetic shielding. The metal housing 20 is constructed by assembling multiple members together. The metal housing 20 has an opening 21 for a connector 50 for connecting to an external device. The illustrated metal housing 20 is constructed by assembling two metal members in the Z direction. The first metal member includes a top wall 23 (upper wall), side walls 24, and a rear wall 25, which will be described later. The second member includes a lower wall on which a base 27 is provided. The metal housing 20 has a substantially rectangular shape when viewed from above in the Z direction. The opening 21 is provided on one side of the metal housing 20. A plurality of openings 21 are provided on one side.

[0017] The metal housing 20 has a top wall 23, side walls 24, and a rear wall 25 as wall portions that define a connector accommodating space 22 that is continuous with the opening 21. The connector accommodating space 22 is a portion of the accommodating space provided by the metal housing 20 that accommodates the connector 50. The connector accommodating space 22 is partitioned from an electronic component accommodating space 26 that accommodates the electronic component 40. The metal housing 20 has connector accommodating spaces 22 corresponding to the number of connectors 50. The illustrated metal housing 20 has a plurality of connector accommodating spaces 22. At least one of the connector accommodating spaces 22 accommodates the connector 50 and the photoelectric conversion unit 55.

[0018] The top wall 23 may form the outer periphery of the metal housing 20, or may be provided separately from the wall portion that forms the outer periphery of the metal housing 20. The illustrated top wall 23 is a part of the outer periphery (upper wall) of the metal housing 20. The top wall 23 is disposed above the connector 50 in the Z direction. The side walls 24 are disposed on both sides of the connector 50 in the X direction. The side walls 24 are disposed so that the connector 50 is located between one side wall 241 and the other side wall 242 of the side walls 24. In the Z direction, the upper ends of the side walls 24 are continuous with the top wall 23, and the lower ends extend to the upper surface of the printed circuit board 30.

[0019] The rear wall 25 is continuous with the rear ends of the top wall 23 and the side walls 24 in the Y direction. In the Z direction, the upper end of the rear wall 25 is continuous with the top wall 23, and the lower end extends to the upper surface of the printed circuit board 30. The illustrated connector accommodating space 22 has a substantially rectangular parallelepiped shape. In the Y direction, the front end side of the connector accommodating space 22 is open via the opening 21, and the rear end side is closed by the rear wall 25. The lower ends of the side walls 24 and the rear wall 25 are electrically connected to a ground land 31 (described below) along their entire lengths.

[0020] The metal housing 20 has a plurality of pedestals 27 that support the printed circuit board 30. The illustrated pedestals 27 protrude in the Z direction from the inner surface of the outer shell (bottom wall) of the metal housing 20. At least a portion of the pedestal 27 provided on the connector 50 side in the Y direction is electrically connected to a ground land 32, which will be described later. The side wall 24, the rear wall 25, the ground lands 31 and 32, and a ground pattern (not shown) of the printed circuit board 30 provide electromagnetic shielding between the connector accommodating space 22 and the electronic component accommodating space 26.

[0021] The metal housing 20 is attached to a predetermined position in the vehicle and is electrically connected to a member that provides a ground potential (vehicle ground) in the vehicle, such as the body or chassis.

[0022] The printed circuit board 30 may also be referred to as a board, a wiring board, or the like. The thickness direction of the printed circuit board 30 is approximately parallel to the Z direction. The planar shape of the printed circuit board 30 is not particularly limited. The illustrated printed circuit board 30 has an approximately rectangular shape when viewed in plan in the Z direction. The printed circuit board 30 includes an insulating substrate and wiring elements disposed on the insulating substrate. The insulating substrate is formed using an electrically insulating material such as resin. The insulating substrate may contain only resin, or may be a combination of glass cloth, nonwoven fabric, or the like with resin.

[0023] The wiring elements are formed using a metal material with good conductivity, such as Cu. The wiring elements include a conductor pattern. The conductor pattern may be referred to as wiring, wiring pattern, etc. The conductor pattern may be formed, for example, by patterning a metal foil, or by printing. The wiring elements may include, in addition to the conductor pattern, a through-hole land or a via conductor. The through-hole land is formed on the wall surface of a through-hole that penetrates the printed circuit board 30 in the Z direction. The via conductor is formed by arranging a conductor, such as plating, in a through-hole (via) formed in an insulating layer that constitutes the insulating base material. The via conductor electrically connects, for example, conductor patterns arranged on different layers.

[0024] The printed circuit board 30 is a multi-layer board. The wiring layers are arranged in multiple layers on the insulating base material. The conductor patterns are arranged on the surface layer of the upper surface, which is the surface on which the connector 50 is arranged in the Z direction, the surface layer of the lower surface, and inside the insulating base material. The conductor patterns include a ground pattern that provides a reference potential (ground potential) on the printed circuit board 30, signal wiring, etc. The ground pattern is wiring that has a larger area than other conductor patterns in order to provide the reference potential. The ground pattern is sometimes called a solid ground, etc.

[0025] The illustrated printed circuit board 30 has ground lands 31 and 32 as conductor patterns. The ground lands 31 and 32 are electrically connected to a ground pattern (not shown). The ground lands 31 and 32 are connected to an inner-layer ground pattern through via conductors. The ground lands 31 and 32 are located on the connector 50 side in the Y direction. The ground lands 31 and 32 are located near the connector 50.

[0026] The ground land 31 is disposed on the upper surface of the printed circuit board 30. The ground land 31 is provided along the lower edges of the side wall 24 and the rear wall 25. The side wall 24 and the rear wall 25 are electrically connected to the ground land 31 via a conductive gasket or the like (not shown). The ground land 31 is electrically connected to the side wall 24 and the rear wall 25 along the entire length of its lower edge. The ground land 32 is disposed on the lower surface of the printed circuit board 30. The ground land 32 extends, for example, in the X direction. The ground lands 31 and 32 are electrically connected to the ground pattern on the inner layer by a shield wall formed by a plurality of via conductors arranged at a predetermined pitch.

[0027] The electronic components 40 are mounted on the printed circuit board 30. A plurality of electronic components 40 are mounted on the printed circuit board 30. The electronic components 40 are generally arranged on at least one of the upper and lower surfaces of the printed circuit board 30. At least a portion of the electronic components 40 may be embedded in an insulating substrate. Exemplary electronic components 40 are arranged on the upper and lower surfaces.

[0028] The electronic components 40, together with the wiring elements described above, form a circuit. The illustrated electronic components 40 include components that constitute an arithmetic processing circuit, a power supply circuit, and the like. The electronic device 10 is an electronic control unit (ECU). ECU is an abbreviation for electronic control unit. The arithmetic processing circuit includes a processor, RAM, storage, and the like. RAM is an abbreviation for random access memory. The processor includes, for example, a CPU, and the like. CPU is an abbreviation for central processing unit. The processor is coupled to the RAM, and by accessing the RAM, the electronic device 10 (electronic control device) executes various processes to realize each function. The storage includes a non-volatile storage medium such as a flash memory. The storage stores a control program executed by the processor.

[0029] The connector 50 mates with an external connector, enabling transmission of signals and the like between the external device and the electronic device 10. The connector 50 is disposed in the metal housing 20 so as to be connectable to the external connector through the opening 21. The connector 50 is an example of an optical connector. The connector 50 mates with the external connector, optically coupling the optical fiber cable of the external connector to an optoelectric conversion unit 55. The connector 50 includes a terminal 51, a housing 52, and a shield shell 53. The connector 50 is mounted on the printed circuit board 30.

[0030] The terminal 51 is accommodated in the housing 52. The terminal 51 protrudes from a partition wall 522 of the housing 52 toward the opening 21 so as to be connectable to an external connector. The terminal 51 has, for example, a ferrule, an optical fiber, and a sleeve. The ferrule is formed using a ceramic material such as zirconia. The ferrule is formed in a substantially cylindrical shape, and the optical fiber is held within the ferrule tube. The optical axis of the optical fiber is substantially parallel to the Y direction. The sleeve is also formed using the same material as the ferrule. The sleeve is formed in a substantially cylindrical shape. The ferrule and optical fiber are inserted and arranged in the sleeve from the rear end side to partway along the tube. The ferrule of the external connector is inserted into the sleeve.

[0031] The housing 52 is, for example, a resin molded body. The illustrated housing 52 has a cylindrical portion 521 and a partition wall 522. Such a housing 52 is sometimes referred to as a header housing. As shown in FIG. 5, the cylindrical portion 521 has a substantially rectangular ring shape when viewed from above in the Y direction. The cylindrical portion 521 extends in the Y direction. The partition wall 522 is provided midway along the cylindrical portion 521 in the Y direction. The partition wall 522 blocks the space inside the cylinder.

[0032] The partition wall 522 and a portion of the cylindrical portion 521 closer to the opening 21, i.e., a portion on the front end side, form a fitting portion with an external connector. The partition wall 522 and a portion of the cylindrical portion 521 deeper than the partition wall 522, i.e., a portion on the rear end side, form a housing chamber for the photoelectric conversion unit 55. A notch is provided in the wall of the cylindrical portion 521 that forms the housing chamber and faces the printed circuit board 30, for electrically connecting the photoelectric conversion unit 55 to the printed circuit board 30. A through hole is provided in the partition wall 522. A portion of the terminal 51 is arranged on the fitting portion side through the through hole, and another portion is arranged within the housing chamber.

[0033] The shield shell 53 is formed using a metal material suitable for electromagnetic shielding. The shield shell 53 may also be referred to as a metal shell, a connector shell, or the like. The shield shell 53 is arranged so as to cover at least a portion of the housing 52. In the case of an optical connector, the shield shell 53 is arranged so as to cover the photoelectric conversion unit 55. In the case of an optical connector, for example, the shield shell 53 may be arranged so as to cover the portion of the housing 52 from the partition wall 522 to the rear end side, or the shield shell 53 may be arranged so as to cover the front end of the tubular portion 521.

[0034] The illustrated shield shell 53 is arranged to cover the cylindrical portion 521 up to the front end. The shield shell 53 is arranged to cover the entire housing 52. The shield shell 53 has a top wall 531, side walls 532, and a rear wall 533. The top wall 531 covers the upper wall of the cylindrical portion 521 of the housing 52. The top wall 531 is arranged to face the top wall 23. The side walls 532 cover the side walls of the cylindrical portion 521. The side walls 532 are arranged to face the side walls 24. The side walls 532 are arranged on both sides of the housing 52 in the X direction. In the Z direction, the upper ends of the side walls 532 are continuous with the top wall 531, and the lower ends extend to near the lower end of the housing 52.

[0035] The rear wall 533 is disposed to face the rear wall 25. The rear wall 533 is continuous with the rear ends of the top wall 531 and the side wall 532 in the Y direction. In the Z direction, the upper end of the rear wall 533 is continuous with the top wall 531, and the lower end extends to near the lower end of the housing 52. In implementation, a gap 70 is formed between the shield shell 53 and the metal casing 20.

[0036] The photoelectric conversion unit 55 includes a photoelectric conversion element and a circuit chip (not shown). The photoelectric conversion element converts signals into electric signals. In the case of a light-emitting element that converts an electric signal into an optical signal, a surface-emitting laser such as a VCSEL is used as the photoelectric conversion element. VCSEL is an abbreviation for Vertical Cavity Surface Emitting Laser. In the case of a light-receiving element that converts an optical signal into an electric signal, a PD is used as the photoelectric conversion element. PD is an abbreviation for Photo Diode. One of the above-mentioned terminals 51 is provided for each photoelectric conversion element. The photoelectric conversion unit 55 may have only one photoelectric conversion element or may have multiple photoelectric conversion elements.

[0037] The circuit chip executes predetermined processing between the photoelectric conversion element and a circuit configured to include the electronic components 40. The circuit chip includes a drive circuit for the photoelectric conversion element, a signal amplification circuit, and the like. In this manner, the photoelectric conversion unit 55 has an electric circuit unit. The photoelectric conversion unit 55 is electrically connected to the printed circuit board 30 via a terminal (not shown).

[0038] The grounding member 60 is disposed in a gap 70 between the metal housing 20 and the shielding shell 53, and grounds the shielding shell 53 to the metal housing 20. The grounding member 60 may be provided integrally with, for example, the shielding shell 53. In other words, the grounding member 60 may be provided as a part of the shielding shell 53. The illustrated grounding member 60 is provided integrally with the shielding shell 53. The grounding member 60 has a spring structure such as a finger spring. The grounding member 60 provided in the connector 50 may be referred to as a finger, a connector finger, or the like.

[0039] The grounding member 60 is in an elastically deformed state and is in contact with the metal housing 20. This ensures electrical connection between the metal housing 20 and the shield shell 53. The position of the grounding member 60 will be described later.

[0040] The electronic device 10 may include an internal shield housed in the housing 52 of the connector 50. The internal shield protects the electrical circuit of the photoelectric conversion unit 55 from electromagnetic waves that enter the cylindrical portion 521. The internal shield is disposed in the housing chamber on the rear end side from the partition wall 522, for example.

[0041] <Position of the waveguide, cavity resonance, and grounding member> Next, the effects of the waveguide, cavity resonance, and the position of the grounding member due to the gap will be described with reference to FIGS. 2 to 7. FIG. 4 is a diagram showing a waveguide section formed in the gap between a metal housing and a shielding shell. FIG. 4 is a development view of the gap (waveguide section). FIG. 5 is a diagram showing the electric field strength distribution in a reference example. In the reference example, the grounding member is provided at the center of the first waveguide section in the Y direction. FIG. 6 is a diagram showing the electric field strength distribution in the electronic device according to this embodiment. FIGS. 5 and 6 show the results of an electromagnetic field simulation. FIG. 7 is a diagram showing the effect of cavity resonance suppression depending on the position of the grounding member. FIG. 7 shows the electric field strength in the frequency band (EMC test band) required for vehicle EMC testing. The EMC test band is, for example, 150 kHz to 6 GHz. Because cavity resonance occurs in the GHz band, the electromagnetic field simulation was performed at 0.5 GHz to 6 GHz. In FIG. 7, the dashed line indicates the reference example, and the solid line indicates the electronic device according to this embodiment. 7, the upper end of the second waveguide section 72, that is, the vicinity of the rear end of the first waveguide section 71, is set as the measurement point E1, as shown in FIGS.

[0042] As shown in FIGS. 2 and 3 , the gap 70 between the metal housing 20 and the shield shell 53 of the connector 50 can be considered a waveguide. The gap 70 functions as a waveguide. The gap 70 includes a first waveguide portion 71 and a second waveguide portion 72. The first waveguide portion 71 includes the top wall 23 and the side wall 24 of the metal housing 20 and the top wall 531 and the side wall 532 of the shield shell 53. The first waveguide portion 71 has a substantially U-shaped opening when viewed from the Y direction. In the illustrated example, the front end 711 of the first waveguide portion 71 is substantially flush with the opening 21. The second waveguide portion 72 is continuous with the rear end 712 of the first waveguide portion 71 and includes the rear wall 25 of the metal housing 20 and the rear wall 533 of the shield shell 53. The front end 711 of the first waveguide portion 71 faces the opening 21.

[0043] The electromagnetic noise passes through the first waveguide portion 71. 01 The electromagnetic noise propagates in a λ / 2 mode. As shown in the development view of FIG. 4, the second waveguide section 72 has a shorter long side length La of the waveguide than the first waveguide section 71. In other words, the second waveguide section 72 has a higher cutoff frequency fc than the first waveguide section 71. Electromagnetic noise is rapidly attenuated without propagating through the second waveguide section 72. Therefore, as in the electronic device 10R of the reference example shown in FIG. 5, a cavity resonance with antinodes occurs at the front end 711 and rear end 712 of the first waveguide section 71, resulting in a strong electric field at the resonant frequency. The dashed line in FIG. 5 indicates the electric field distribution.

[0044] In the electronic device 10 of this embodiment, the grounding member 60 is disposed in a region within a predetermined range from at least one of the front end 711 and rear end 712 of the first waveguide section 71. The shielding shell 53 is grounded to the metal housing 20 within this predetermined range from the end. The predetermined range is a range of ¼ wavelength or less at the maximum frequency required for EMC testing. In the example, the maximum frequency is 6 GHz, and the ¼ wavelength is approximately 6 mm. As shown in FIGS. 2, 3, and 6, the illustrated grounding member 60 is provided in a region (rear end region) within a predetermined range from the rear end 712 of the first waveguide section 71.

[0045] When the grounding member 60 is provided in a region within a predetermined range from the end of the first waveguide portion 71, that is, when the shielding shell 53 is grounded to the metal housing 20 at or near the antinode of the electric field, the mode of the resonant circuit changes. As shown in Figure 7, the resonant frequency shifts to the high frequency side, and the electric field strength decreases across the entire frequency range, including the resonant frequency. This makes it possible to suppress cavity resonance.

[0046] When the grounding member 60 is provided on the rear end 712 side as illustrated, the electric field intensity on the rear end side, particularly at a position close to the photoelectric conversion unit 55, decreases as shown in Figures 6 and 7. In other words, cavity resonance can be suppressed around the photoelectric conversion unit 55.

[0047] The grounding member 60 may be disposed in the first waveguide section 71 between the top wall 23 of the metal housing 20 and the top wall 531 of the shield shell 53, or may be disposed between the side wall 24 and the side wall 532. It is preferable to dispose it near the center of the long side of the first waveguide section 71. In other words, it is preferable to dispose it between the top wall 23 and the top wall 531. In the illustrated electronic device 10, the grounding member 60 is provided between the top wall 23 and the top wall 531. Furthermore, the grounding member 60 is provided to have approximately the same length as the top wall 531 in the X direction.

[0048] <Summary of the First Embodiment> The electronic device 10 of this embodiment includes a metal housing 20, a connector 50 having a shield shell 53, and a grounding member 60. A gap 70 between the metal housing 20 and the connector 50 includes a first waveguide section 71 including the top wall 23 and side wall 24 of the metal housing 20 and the shield shell 53, and a second waveguide section 72 including the rear wall 25 and the shield shell 53. The grounding member 60 is disposed in an area within a predetermined range from at least one of a front end 711 and a rear end 712, which are the ends of the first waveguide section 71 on the opening 21 side.

[0049] As mentioned above, EMC requirements have become more frequent; specifically, the maximum frequency required for EMC testing has been increased from approximately 2 GHz to 6 GHz, which has made cavity resonance in the gap 70 more apparent. In the gap 70 between the shielding shell 53 and the metal housing 20, cavity resonance occurs, with electric field loops at the front end 711 and rear end 712 of the first waveguide section 71. The grounding member 60 is provided in a predetermined area from the end of the first waveguide section 71, and the shielding shell 53 is grounded to the metal housing 20 at or near the electric field loop. This changes the mode of the resonant circuit and suppresses cavity resonance. This, in turn, can prevent malfunctions of the electrical circuit.

[0050] As illustrated, the grounding member 60 may be disposed at least on the rear end 712 side. As described above, by grounding the shielding shell 53 to the metal housing 20 at the antinode position on the rear end 712 side, the mode of the resonant circuit can be changed and cavity resonance can be suppressed.

[0051] As shown in the example, in a configuration in which the connector 50 is an optical connector and includes a photoelectric conversion unit 55 that is arranged closer to the rear end than the terminal 51 and covered by a shield shell 53, the grounding member 60 may be arranged only on the rear end 712 side. This makes it possible to suppress cavity resonance on the rear end 712 side, i.e., around the photoelectric conversion unit 55. Of the elements arranged in the connector accommodating space 22, the electrical circuit unit of the photoelectric conversion unit 55 is affected by electromagnetic noise, so this arrangement makes it possible to suppress malfunction of the electrical circuit unit. Malfunction can be suppressed with a simple configuration.

[0052] As shown in the example, it is preferable to provide the ground member 60 within a range of ¼ wavelength or less from the end at the maximum frequency required for EMC testing, thereby making it possible to suppress cavity resonance in the frequency band required for EMC testing (EMC test band).

[0053] As shown in the example, the grounding member 60 may be provided as a part of the shield shell 53. This allows for a simplified configuration. The grounding member 60 may also have a spring structure. The elastic deformation of the grounding member 60 makes it easier to ensure electrical connection between the shield shell 53 and the metal housing 20. Furthermore, the electrical connection between the shield shell 53 and the metal housing 20 can be ensured by assembling the shield shell 53 and the metal housing 20.

[0054] <Modification> Although an example has been shown in which the grounding member 60 is provided as a part of the shield shell 53, the present invention is not limited to this. The grounding member 60 may be provided integrally and continuously with the metal housing 20. In other words, the grounding member 60 may be provided as a part of the metal housing 20.

[0055] The shape of the grounding member 60 is not limited to the above example. For example, as shown in Fig. 8, a grounding member 60 having a substantially V-shape in a plan view in the X direction may be used.

[0056] (Second embodiment) This embodiment is a modification based on the preceding embodiment, and the description of the preceding embodiment can be used. In the preceding embodiment, an optical connector is shown. Alternatively, an electrical connector may be used. In the preceding embodiment, a grounding member is provided only at the rear end. Alternatively, a grounding member may be provided at the front end.

[0057] FIG. 9 is a cross-sectional view showing an electronic device according to this embodiment. FIG. 9 corresponds to FIG. 2. FIG. 9 shows only some of the wiring elements of the printed circuit board. Also, the structure of the connector terminals, photoelectric conversion unit, etc. is shown in a simplified form. FIG. 10 is a perspective view showing the periphery of the connector. FIG. 10 corresponds to FIG. 3. FIG. 10 shows a simplified form of the connector. Also, only the elements of the metal housing that define one connector accommodating space are shown. FIG. 11 is a diagram showing the positional relationship between the waveguide unit and the grounding member.

[0058] Fig. 12 is a diagram showing the effect of cavity resonance suppression. Fig. 12 corresponds to Fig. 7. Fig. 12 also shows the electric field intensity in the EMC test band (0.5 GHz to 6 GHz). In Fig. 12, as shown in Fig. 11, measurement point E1 is near the rear end of the first waveguide section 71, and measurement point E2 is near the front end of the first waveguide section 71. In Fig. 12, measurement point E1 in the case where grounding members are present at both ends is shown by a solid line, and measurement point E2 in the case where grounding members are not present at both ends is shown by a dashed line, and measurement point E2 in the case where grounding members are not present at both ends is shown by a two-dot chain line.

[0059] The electronic device 10 includes a connector 50A. The connector 50A is an electrical connector. In the connector 50A, terminals 51 are housed in a housing 52 and are held by the housing 52. In the longitudinal direction of the terminals 51, one end of the terminals 51 protrudes from the partition wall 522 toward the opening 21, and the other end is mounted on the printed circuit board 30. A shield shell 53 covers the terminals 51. The illustrated shield shell 53 has a top wall 531, side walls 532, and a rear wall 533, similar to the previous embodiment.

[0060] The electronic device 10 includes ground members 61 and 62 as the ground member 60. The ground member 61 has the same configuration as the ground member 60 shown in the preceding embodiment. The ground member 61 is provided in an area on the rear end 712 side of the first waveguide section 71. The ground member 62 is provided in an area on the front end 711 side of the first waveguide section 71. The illustrated ground members 61 and 62 are both provided integrally with the top wall 531. The ground members 61 and 62 have approximately the same length in the X direction as the top wall 531. The other configurations are the same as the configurations shown in the preceding embodiment.

[0061] When the grounding members 60 are provided at both the front end 711 and the rear end 712 of the first waveguide portion 71, the resonance frequency at both measurement points E1 and E2 shifts to the higher frequency side, and the electric field strength decreases across the entire frequency range, including the resonance frequency, as shown in Fig. 12. Therefore, cavity resonance can be suppressed.

[0062] <Summary of the second embodiment> As shown in the example, when the connector 50A is an electrical connector and the shield shell 53 is configured to cover the terminals 51, the grounding members 60 may be disposed on both the front end 711 side and the rear end 712 side. In the case of an electrical connector, it is necessary to consider the electrical circuit including the terminals 51. The terminals 51 extend in the Y direction and are also present on the opening 21 side of the partition wall 522. Therefore, by providing the grounding members 61, 62, it is possible to suppress cavity resonance over the entire area where the terminals 51 are present. With a simple configuration, it is possible to suppress malfunction of the electrical circuit including the terminals 51.

[0063] <Modification> In a configuration including connector 50A (electrical connector), grounding member 60 may be disposed only on the front end 711 side. Electromagnetic noise enters connector accommodating space 22 from the opening 21 side. Therefore, by grounding shield shell 53 to metal housing 20 at the antinode position of front end 711, which is the entrance side, the mode of the resonant circuit can be changed and cavity resonance can be suppressed.

[0064] In a configuration including the connector 50 (optical connector) shown in the preceding embodiment, the grounding members 60 may be provided on both the front end 711 and the rear end 712.

[0065] (Third embodiment) This embodiment is a modification of the preceding embodiment as a basic form, and the description of the preceding embodiment can be used. This embodiment shows a configuration that can be combined with the preceding embodiment.

[0066] Fig. 13 is a perspective view showing the periphery of the connector in the electronic device according to this embodiment. Fig. 13 corresponds to Fig. 3. Fig. 13 shows a simplified view of the connector. Also, only the elements of the metal casing that define one connector accommodating space are shown. Fig. 14 is a diagram showing a waveguide section formed in the gap between the metal casing and the shield shell. Fig. 14 corresponds to Fig. 4. Fig. 14 is a development view of the gap (waveguide section).

[0067] In addition to the configuration described in the first embodiment, the electronic device 10 further includes a metal member 80. The metal member 80 is arranged in the first waveguide portion 71 so as to narrow the long side of the first waveguide portion 71. The metal member 80 is electrically connected to at least one of the top wall 23 and the side wall 24 and the shield shell 53.

[0068] The illustrated metal member 80 is disposed between the side wall 241 and the side wall 532 of the shield shell 53, and between the side wall 242 and the side wall 532 of the shield shell 53. By disposing the metal member 80 and electrically connecting the shield shell 53 and the metal casing 20 via the metal member 80, the long side length La of the first waveguide portion 71 is shortened as shown in FIG.

[0069] The illustrated metal member 80 is arranged so that the long side length La of the first waveguide portion 71 excluding the metal member 80 is λc / 2 or less, where fc is the maximum frequency required for EMC testing and λc is the wavelength corresponding to the cutoff frequency fc. The other configurations are the same as those shown in the preceding embodiment.

[0070] <Summary of the third embodiment> As illustrated, a metal member 80 may be disposed in the first waveguide portion 71 so as to narrow the long side of the first waveguide portion 71, and the metal member 80 may electrically connect at least one of the top wall 23 and the side wall 24 to the shield shell 53. This shortens the long side length La of the first waveguide portion 71, thereby increasing the cutoff frequency fc. This makes it possible to suppress the propagation of electromagnetic noise below the cutoff frequency fc. By combining this with the preceding embodiment, it is possible to effectively suppress malfunctions of the electrical circuit section.

[0071] As illustrated, the metal member 80 may be disposed both between the side wall 241 (first side wall) and the shield shell 53 and between the side wall 242 (second side wall) and the shield shell 53. It is easier to dispose the metal member 80 between the side wall 24 and the side wall 532 of the shield shell 53. For example, the metal member 80 may be disposed on the printed circuit board 30. With a simple configuration, malfunction of the electrical circuit section can be effectively suppressed. Note that the metal member 80 may be disposed at least either between the side wall 241 (first side wall) and the shield shell 53 or between the side wall 242 (second side wall) and the shield shell 53.

[0072] As shown in the example, if the maximum frequency required for EMC testing is defined as cutoff frequency fc and the wavelength corresponding to cutoff frequency fc is defined as cutoff wavelength λc, metal member 80 may be arranged so that the long side length La of first waveguide portion 71 excluding metal member 80 is λc / 2 or less. This makes it possible to suppress the propagation of electromagnetic noise below the maximum frequency of the EMC test band, for example, below 6 GHz. Therefore, when combined with the preceding embodiment, it is possible to effectively suppress malfunction of the electric circuit unit across the entire EMC test band.

[0073] <Modification> As shown in FIG. 15, instead of arranging a metal member 80, a choke structure 28 may be provided on a wall portion constituting the first waveguide portion 71 of the metal housing 20. The illustrated choke structure 28 is provided on the inner surface of the side wall 24. The choke structure 28 has a groove structure that has a predetermined depth in the X direction and extends in the Z direction. The depth of the groove is ¼ wavelength of the predetermined frequency. This makes it possible to suppress the propagation of electromagnetic noise of the predetermined frequency.

[0074] 15, multiple grooves are provided periodically. The multiple grooves are provided at a predetermined pitch in the Y direction. For example, the multiple grooves may have different depths to suppress the propagation of electromagnetic noise in a predetermined frequency band.

[0075] The choke structure 28 may be provided on the top wall 23. The choke structure 28 may be a single groove.

[0076] (Other embodiments) The disclosure in this specification and drawings, etc. is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and modifications thereto by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and / or elements from the embodiments. The disclosure encompasses the substitution or combination of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. Some disclosed technical scopes are defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0077] The disclosure in the specification, drawings, etc. is not limited by the claims. The disclosure in the specification, drawings, etc. encompasses the technical ideas described in the claims, and extends to more diverse and broader technical ideas than the technical ideas described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being bound by the claims.

[0078] When an element or layer is referred to as being "on," "coupled," "connected," or "bonded," it may be directly on, coupled, connected, or bonded to another element or layer, and intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly coupled," "directly connected," or "directly bonded" to another element or layer, no intervening elements or layers are present. Other terms used to describe relationships between elements should be construed in a similar manner (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). As used in this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items. That is, reference to A and / or B means at least one of A and B.

[0079] Spatially relative terms such as "inside," "outside," "back," "below," "low," "top," "top," and the like are used herein to facilitate the description of one element or feature's relationship to other elements or features, as illustrated. Spatially relative terms may be intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures were turned over, elements described as "below" or "directly below" other elements or features would then be oriented "above" the other elements or features. Thus, the term "bottom" can encompass both an orientation of top and bottom. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used in this specification would be interpreted accordingly. [Explanation of symbols]

[0080] 10...electronic device, 20...metal housing, 21...opening, 22...connector accommodating space, 23...ceiling wall, 24, 241, 242...side wall, 25...rear wall, 26...electronic component accommodating space, 27...base, 28...choke structure portion, 30...substrate, 31, 32...ground land, 40...electronic component, 50, 50A...connector, 51...terminal, 52...housing, 521...tubular portion, 522...partition wall, 53...shield shell, 531...ceiling wall, 532...side wall, 533...rear wall, 55...photoelectric conversion portion, 60, 61, 62...grounding member, 70...gap, 71...first waveguide portion, 711...front end, 712...rear end, 72...second waveguide portion, 80...metal member

Claims

1. a metal housing (20) having an opening (21) and providing a ground potential; a connector (50, 50A) having terminals (51), a housing (52) for accommodating the terminals, and a shield shell (53) for covering at least a portion of the housing, the connector being disposed in the metal casing so as to be connectable to an external connector through the opening; a grounding member (60) disposed in a gap (70) between the metal housing and the shield shell, for grounding the shield shell to the metal housing; Equipped with The metal housing faces the shield shell and has a top wall (23), a side wall (24), and a rear wall (25) as wall portions defining a connector accommodating space (22) that is continuous with the opening, the gap includes a first waveguide portion (71) including the top wall, the side wall, and the shield shell, and a second waveguide portion (72) connected to a rear end of the first waveguide portion and including the rear wall and the shield shell, The electronic device, wherein the grounding member is disposed in an area within a predetermined range from at least one of the front end and the rear end, which are the ends of the first waveguide portion on the opening side.

2. The electronic device according to claim 1 , wherein the grounding member is disposed at least on the rear end side.

3. the connector is an optical connector, a photoelectric conversion unit (55) that is disposed closer to the rear end than the terminal and is covered by the shield shell; The electronic device according to claim 2 , wherein the grounding member is disposed only on the rear end side.

4. the connector is an electrical connector; the shield shell covers the terminal, The electronic device according to claim 2 , wherein the grounding members are disposed on both the rear end side and the front end side.

5. 5. The electronic device according to claim 1, wherein the area is within a range of 1 / 4 wavelength or less from the end at a maximum frequency of an EMC test requirement.

6. 2. The electronic device according to claim 1, further comprising: a metal member (80) disposed in the first waveguide section so as to narrow a long side of the first waveguide section, the metal member (80) being electrically connected to at least one of the top wall and the side wall and the shielding shell.

7. The side walls include a first side wall (241) and a second side wall (242) provided so that the connector is positioned between the first side wall and the second side wall, The electronic device according to claim 6 , wherein the metal member is disposed at least one of between the first side wall and the shielding shell and between the second side wall and the shielding shell.

8. If the maximum frequency of the EMC test requirement is the cutoff frequency fc and the wavelength corresponding to the cutoff frequency fc is the cutoff wavelength λc, then:

8. The electronic device according to claim 6, wherein a length of a long side of the first waveguide portion excluding the metal member is λc / 2 or less.

9. The electronic device according to claim 1 , wherein the metal housing has a choke structure (28) in the wall portion that defines the first waveguide portion.

10. The electronic device according to claim 1 , wherein the grounding member is provided as a part of the shielding shell.

11. The electronic device according to claim 1 , wherein the grounding member is provided as a part of the metal housing.

12. The electronic device according to claim 10 or 11, wherein the grounding member has a spring structure.

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