Electronic device

Abstract

To provide an electronic device with a flexible substrate having improved durability under a vibration environment.SOLUTION: An electronic device includes a front-side rigid substrate 15a, a chassis-side rigid substrate 15b, a flexible substrate 16 connecting the front-side rigid substrate 15a and the chassis-side rigid substrate 15b to each other, and an insulating sheet 17 provided in the inner side of the bottom surface part 13, in a housing having a front part 11, a back chassis part 12, a bottom surface part 13, and an upper surface part 14. A part of the flexible substrate 16 is in contact with the insulating sheet 17 so that motions of the flexible substrate 16 in a vibration environment are suppressed and the load is reduced.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electronic device having a flexible substrate and incorporating electronic components, and more particularly to an electronic device capable of improving durability in an environment where vibration occurs. [Background technology]

[0002] [Prior Art] 2. Description of the Related Art Electronic devices installed in moving vehicles such as aircraft or vehicles incorporate a plurality of electronic components. Some electronic devices are equipped with printed circuit boards (rigid boards) that are hard and difficult to deform, and others with flexible boards (flex boards) that can be bent. Rigid boards have wiring patterns formed on them and electronic components mounted on them, while flexible boards are mainly used for wiring in moving parts and in narrow spaces.

[0003] [Conventional electronic device: Figure 4] The schematic configuration of a conventional electronic device will be described with reference to Fig. 4. Fig. 4 is an explanatory diagram showing an example of the schematic configuration of a conventional electronic device. As shown in FIG. 4, a conventional electronic device has a housing that forms the external shape of the device main body 2, which includes a front portion 21 that constitutes the front side, a chassis portion 22 that constitutes the rear side (back side), a bottom portion 23, and a top portion 24.

[0004] A plurality of rigid boards 25 are stored inside the housing, and flexible board 26 is attached so as to connect between rigid boards 25. In the example of Fig. 4, flexible board 26 is attached so as to connect the lower end of rigid board 25a on the front portion 21 side and the lower end of rigid board 25b on the chassis portion 22 side. Although not shown, various electronic components are mounted on the rigid board 25 and wiring is formed thereon.

[0005] In conventional electronic devices, flexible board 26 is curved and attached to bottom portion 23 without contacting it so as to connect rigid boards 25a, 25b to be connected over the shortest distance, forming an aerial wiring. Specifically, one end of flexible substrate 26 is connected to rigid substrate 25a and the other end is connected to rigid substrate 25b, so that both ends are fixed, but the rest of the substrate is suspended in the air. Therefore, when an electronic device mounted on an aircraft or the like vibrates, the flexible board also vibrates accordingly.

[0006] [Related Technology] Incidentally, a related prior art is "Video Camera" (Patent Document 1) disclosed in Japanese Patent Laid-Open Publication No. 2001-275022. Patent document 1 shows a video camera in which a first flexible board connecting a first board and a second board, and a second flexible board connecting the second board and a third board, are bent so that they do not face each other and assembled inside a housing, and the first and second flexible boards are pressed inward to hold the second board. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2001-275022 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, in conventional electronic devices, the flexible board is suspended in mid-air by aerial wiring, and in a vibrating environment, the flexible board swings and is subjected to load (stress), which can cause cracks and lead to failure.

[0009] Furthermore, Patent Document 1 does not disclose a configuration in which the flexible board is formed to be longer than the length to be connected and mounted so that it is in contact with an insulating sheet provided on the bottom surface inside the housing, thereby suppressing movement of the flexible board.

[0010] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide an electronic device that can reduce the load on a flexible board in a vibration environment and improve durability and reliability. [Means for solving the problem]

[0011] The present invention, which solves the problems of the above-mentioned conventional examples, is an electronic device incorporating electronic components, and comprises a front portion on the front side, a chassis portion on a back side, a bottom portion, a top portion, a front-side rigid board attached to the front portion, a chassis-side rigid board attached to the chassis portion, a flexible board connecting the front-side rigid board and the chassis-side rigid board, and an insulating sheet provided on the inner surface of the bottom portion, and is characterized in that a portion of the flexible board is formed so as to be in contact with the insulating sheet.

[0012] Furthermore, the present invention is characterized in that in the electronic component, the insulating sheet with which the flexible substrate is in contact is formed to have an area larger than an area of ​​the portion of the flexible substrate that is in contact with the insulating sheet.

[0013] The present invention is also characterized in that, in the above-mentioned electronic device, when a middle portion of the flexible substrate is capable of coming into contact with another substrate due to vibration, a sponge is provided at the portion of the other substrate that is capable of coming into contact with the flexible substrate.

[0014] In addition, the present invention is characterized in that, in the above-mentioned electronic device, the shape of the portion of the flexible board that connects to the front side rigid board or the chassis side rigid board is curved and widens toward the end that connects to the front side rigid board or the chassis side rigid board.

[0015] Furthermore, the present invention is characterized in that in the electronic device, the position of the front-side rigid board to which the flexible board is connected and the position of the chassis-side rigid board to which the flexible board is connected are parallel and face each other. Effect of the Invention

[0016] According to the present invention, an electronic device incorporating electronic components is provided with a front portion on the front side, a chassis portion on the back side, a bottom portion, a top portion, a front-side rigid board attached to the front portion, a chassis-side rigid board attached to the chassis portion, a flexible board connecting the front-side rigid board and the chassis-side rigid board, and an insulating sheet provided on the inner surface of the bottom portion, with a portion of the flexible board being formed to be in contact with the insulating sheet.Since the flexible board is in contact with the inner bottom surface of the housing, vibrations can be suppressed, the load on the flexible board can be reduced to prevent damage, and durability and reliability in a vibration environment can be improved.

[0017] In addition, according to the present invention, when an intermediate portion of the flexible substrate is capable of coming into contact with another substrate due to vibration, the electronic device is provided with a sponge at the portion of the other substrate that is capable of contacting the flexible substrate. Therefore, even if an intermediate portion of the flexible substrate comes into contact with the other substrate due to vibration, the sponge absorbs the impact, thereby preventing damage to the flexible substrate.

[0018] Furthermore, according to the present invention, in the above-mentioned electronic device, the shape of the portion of the flexible board that connects to the front side rigid board or the chassis side rigid board is curved and widened toward the end that connects to the front side rigid board or the chassis side rigid board. This has the effect of reducing the load on the flexible board at the connection portion with the rigid board, preventing damage and suppressing the occurrence of failures, even in a vibration environment. [Brief description of the drawings]

[0019] [Figure 1]FIG. 2 is an explanatory diagram showing a schematic configuration example of the present device. [Diagram 2] 1 is a schematic cross-sectional view showing a mounting structure for a flexible substrate. [Diagram 3] FIG. 11 is an explanatory diagram showing the shape of a connection portion with a rigid substrate. [Figure 4] FIG. 1 is an explanatory diagram showing a schematic configuration example of a conventional electronic device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. [Outline of the embodiment] An electronic device (this device) according to an embodiment of the present invention is provided with a housing having a front portion on the front side, a chassis portion on the back side, a bottom portion, and a top portion, and is equipped with a front-side rigid board attached to the front portion, a chassis-side rigid board attached to the chassis portion, a flexible board connecting the front-side rigid board and the chassis-side rigid board, and an insulating sheet provided on the inner surface of the bottom portion, with a portion of the flexible board being formed so as to be in contact with the insulating sheet. By keeping the flexible board in contact with the inner bottom surface of the housing via the insulating sheet, vibrations can be suppressed, the load on the flexible board can be reduced, preventing damage, and improving durability in a vibration environment.

[0021] [This device: Figure 1] This device will be described with reference to Fig. 1. Fig. 1 is an explanatory diagram showing an example of the schematic configuration of this device. As shown in FIG. 1, this device has a housing that forms the external shape of the device main body 1, similar to the conventional device shown in FIG. 4, and includes a front portion 11 that forms the front side, a chassis portion 12 that forms the rear side (back side), a bottom portion 13 that serves as the bottom cover, and a top portion 14 that forms the top side. Inside the housing, in addition to a plurality of rigid boards 15 similar to those in the conventional device, there are also a flexible board 16, an insulating sheet 17, and a sponge 18, which are characteristic parts of the device.

[0022] Rigid board 15a is a front-side rigid board attached to front portion 11, and rigid board 15b is a chassis-side rigid board attached to chassis portion 12. In the example of FIG. 2, flexible substrate 16 is attached so as to connect the lower ends of rigid substrate 15a and rigid substrate 15b to each other.

[0023] Here, flexible substrate 16 is formed to have a length with excess length rather than the shortest length required to connect rigid substrates 15a, 15b as in the conventional case, and both ends are connected to rigid substrates 15a, 15b. The excess length is bent and installed so as to abut against and make contact with the inner bottom surface of the housing. By keeping the flexible substrate 16 in contact with the inner bottom surface of the housing, it is possible to prevent the flexible substrate 16 from shaking even if the device vibrates.

[0024] In this device, in order to sufficiently prevent the movement of flexible substrate 16, the ratio (m:L) of the length (m) of flexible substrate 16 to the linear distance (L) between the ends of rigid substrate 15 to be connected (here, the bottom ends of rigid substrate 15a and 15b) is set to 8:5. In other words, the length (m) of the flexible substrate is set to 1.6 times (=m / L) the linear distance (L).

[0025] An insulating sheet 17 is attached to the inside of the bottom surface portion 13, and the flexible substrate 16 is attached in contact with the surface of the insulating sheet 17. The insulating sheet 17 prevents electrical connection between the inner surface of the bottom portion 13 and the flexible substrate 16, and also has anti-slip and vibration absorbing properties depending on the material.

[0026] The insulating sheet 17 is formed to be larger than the shape of the excess portion (middle portion) of the flexible substrate 16 that comes into contact with the insulating sheet 17 so that the excess portion does not protrude. For example, when the width of the flexible substrate 16 is 35 mm, the width and length of the insulating sheet 17 are formed to dimensions of 50 mm x 70 mm, and the insulating sheet 17 is fixed to the inner surface of the bottom portion 13 with double-sided tape.

[0027] In this way, in this device, flexible board 16 is not suspended in mid-air, but is mounted against the inside bottom surface of the housing via insulating sheet 17, making it difficult for flexible board 16 to move even in a vibration environment, reducing stress load and preventing damage, thereby improving durability and reliability.

[0028] Furthermore, in this device, a sponge 18 is attached to the rigid substrate 15 with which the intermediate portion of the flexible substrate 16 (the portion between the end portion and the portion that contacts the inside of the bottom surface) may come into contact, to prevent damage to the flexible substrate 16. The thickness of sponge 18 is formed to be approximately the distance between rigid substrate 15 and flexible substrate 16, and the shape is formed to be larger than the portion of flexible substrate 16 that is likely to come into contact with rigid substrate 15c.

[0029] In the example of Figure 1, sponge 18 is mounted on the surface of rigid substrate 15c, so that even if the middle part of flexible substrate 16 vibrates and comes into contact with it during vibration, sponge 18 absorbs the impact, reduces the load on flexible substrate 16, and prevents damage.

[0030] [Flexible PCB mounting structure: Figure 2] Next, the mounting structure of flexible substrate 16 will be described with reference to Fig. 2. Fig. 2 is a schematic cross-sectional view showing the mounting structure of flexible substrate 16. Fig. 2 shows a cross section of flexible substrate 16 in Fig. 1 cut along a plane passing through the longitudinal direction. 2, in this device, an insulating sheet 17 is attached to the inner surface of bottom portion 13, and rigid boards 15a, 15b, and 15c are mounted on the insulating sheet 17. Rigid boards 15a and 15b are in contact with the inner surface of bottom portion 13 at points other than the cut surfaces.

[0031] One end of flexible substrate 16 is connected to the lower end of rigid substrate 15, bent into a U-shape, and mounted in contact with insulating sheet 17, and the other end is connected to the lower end of rigid substrate 15b.

[0032] Further, a sponge 18 is attached to the surface of the rigid substrate 15c to prevent the flexible substrate 16 from directly contacting the rigid substrate 15c. Furthermore, insulating sheet 17 may be made of a thick and soft material, so that even if flexible board 16 is pressed against bottom portion 13 due to vibration, the impact can be reduced.

[0033] [Connection part with rigid board: Figure 3] Next, the shape of the connection portion between flexible substrate 16 and rigid substrate 15 will be described with reference to Fig. 3. Fig. 3 is an explanatory diagram showing the shape of the connection portion with the rigid substrate. As shown in FIG. 3, flexible substrate 16 has one end, side AB, connected to bottom end A'B' of rigid substrate 15a, and the other end, side CD, connected to bottom end C'D' of rigid substrate 15b.

[0034] Flexible substrate 16 of the present device is basically strip-shaped with parallel straight left and right sides, but corners 5a, 5b, 5c, and 5d of the connection portion that connects to rigid substrate 15 are formed to have an arched shape (R-shape) that is curved like an arc. In other words, flexible substrate 16 is wider at both ends than the middle portion, and the left and right sides widen in an R-shape toward the ends.

[0035] In this way, by lengthening the length of the connection portion with the rigid board 15 and making the corners arc-shaped, it is possible to prevent stress concentration at the connection portion and corners, making the connection portion less susceptible to breakage even if a load is applied to it in a vibrating environment, and thus preventing failure.

[0036] Furthermore, in this device, when flexible substrate 16 is attached to rigid substrates 15a and 15b, flexible substrate 16 is attached so that sides AB and CD at both ends of flexible substrate 16 are parallel and face each other, so that flexible substrate 16 is not twisted.

[0037] Specifically, flexible substrate 16 is attached so that attachment side A'B' of rigid substrate 15a and attachment side C'D' of rigid substrate 15b are parallel to and face each other. This prevents the flexible substrate 16 from twisting, improves its resistance to vibration, prevents breakdowns, and improves reliability.

[0038] When the bottom portion 13 is attached to the front portion 11 and the chassis portion 12, the middle portion of the flexible substrate 16 abuts against an insulating sheet 17 provided on the inside of the bottom portion 13, preventing the flexible substrate 16 from moving.

[0039] [Effects of the embodiment] According to this device, inside a housing having a front portion 11 on the front side, a chassis portion 12 on the back side, a bottom portion 13, and a top portion 14, there are provided a front-side rigid board 15a, a chassis-side rigid board 15b, a flexible board 16 connecting the front-side rigid board 15a and the chassis-side rigid board 15b, and an insulating sheet 17 provided on the inner surface of the bottom portion 13, with a part of the flexible board 16 being formed to be in contact with the insulating sheet 17. By keeping the flexible board 16 in contact with the inner bottom surface of the housing via the insulating sheet 17, it is possible to suppress the movement of the flexible board 16 in a vibration environment, reduce the load on the flexible board 16, prevent damage, and improve durability and reliability in a vibration environment. [Industrial Applicability]

[0040] The present invention is suitable for electronic devices with flexible substrates, which improves durability and reliability in vibration environments. [Explanation of symbols]

[0041] REFERENCE SIGNS LIST 1,2...Device body; 5a,5b,5c,5d...Corner portion; 11,21...Front portion; 12,22...Chassis portion; 13,23...Bottom portion; 14,24...Top portion; 15a,15b,15c,25a,25b...Rigid circuit board; 16,26...Flexible circuit board; 17...Insulating sheet; 18...Sponge

Claims

1. An electronic device incorporating an electronic component, The front part and The chassis part on the back side, A bottom portion and An upper surface portion; a front side rigid board attached to the front portion; a chassis-side rigid board attached to the chassis portion; a flexible board connecting the front-side rigid board and the chassis-side rigid board; an insulating sheet provided on an inner surface of the bottom portion, The electronic device is characterized in that a portion of the flexible substrate is formed so as to be in contact with the insulating sheet.

2. 2. The electronic device according to claim 1, wherein the insulating sheet with which the flexible substrate is in contact is formed to have an area larger than an area of ​​the portion of the flexible substrate that is in contact with the insulating sheet.

3. 3. The electronic device according to claim 1, wherein, when an intermediate portion of the flexible substrate is capable of coming into contact with another substrate due to vibration, a sponge is provided at the portion of the other substrate that is capable of coming into contact with the flexible substrate.

4. 3. The electronic device according to claim 1, wherein the shape of the portion of the flexible board that connects to the front side rigid board or the chassis side rigid board is curved and widens toward the end that connects to the front side rigid board or the chassis side rigid board.

5. 3. The electronic device according to claim 1, wherein a position on the front-side rigid board to which the flexible board is connected and a position on the chassis-side rigid board to which the flexible board is connected are parallel and face each other.

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