Circuit board

Abstract

To suppress the loss of elasticity of the elastic body fixed around the electronic component, and to suppress the application of stress from the elastic body to the electronic component. [Solution] A circuit board 1 comprising an FPC2, a thermistor 3 mounted on the FPC2, a frame component 4 fixed to the surface 2E on which the thermistor 3 of the FPC2 is mounted and surrounding the thermistor 3, a resin material 5 filling the space 4C surrounded by the inner surface of the frame component 4 and covering the thermistor 3, and a sponge 8 fixed around the thermistor 3 on surface 2E, with a thickness in the direction perpendicular to surface 2E being greater than that of the frame component 4 and the resin material 5, and a space being secured between the sponge 8 and the frame component 4.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a circuit board.

Background Art

[0002] Conventionally, a circuit board including a printed circuit board, electronic components mounted on the printed circuit board, and a resin material covering the electronic components has been known (see, for example, Patent Document 1). Specifically, the invention described in Patent Document 1 includes a flexible printed circuit board, a current limiting element mounted on the flexible printed circuit board, and an insulating resin overcoating the current limiting element. Patent Document 1 describes that since the current limiting element is overcoated with an insulating resin, the electrodes of the current limiting element are not short-circuited by water droplets or the like formed due to dew condensation.

[0003] Conventionally, in a circuit board in which electronic components are covered with a resin material, there is also known one in which an elastic body is fixed to the surface on which the electronic components are mounted (see, for example, Patent Document 2). Specifically, the sensor unit described in Patent Document 2 is a sensor unit mounted in a housing provided in a detection object, and includes a strip-shaped conductive path structure body having plasticity in which a conductive path is formed, a sensor element connected to the conductive path on the surface of the conductive path structure body, and an elastic member provided on the surface of the conductive path structure body so as to be elastically deformable and elastically compressed in the housing to press a portion on the back side of the conductive path structure body toward the detection object by elastic force. The sensor element is covered with a mold portion (see paragraphs 0086 to 0090 and FIG. 16 of the same document).

[0004] Patent Document 2 states that by suppressing the back portion of the conductive path structure from lifting away from the object to be detected, and by positioning the sensor element in close proximity to the object to be detected, a decrease in the detection accuracy of the sensor element relative to the object to be detected can be suppressed. It also states that even if the distance between the back portion of the conductive path structure and the object to be detected is narrowed due to dimensional tolerances, the pressing member will be elastically compressed, thus suppressing the crushing and damage of the sensor element (see paragraph 0007 of the same document). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 6894558 (paragraph 0008, Figure 5) [Patent Document 2] Japanese Patent Publication No. 7108009 (paragraphs 0086-0090, Figure 16) [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the sensor unit described in Patent Document 2 had room for improvement in preventing the elasticity of the elastic member from being impaired or stress from being applied from the elastic member to the electronic component. This specification discloses a technique that can suppress the loss of elasticity of an elastic body fixed around an electronic component, and also suppress the application of stress from the elastic body to the electronic component. [Means for solving the problem]

[0007] The circuit board according to this disclosure comprises a printed circuit board, an electronic component mounted on the printed circuit board, a frame component fixed to the surface of the printed circuit board on which the electronic component is mounted and surrounding the electronic component, a resin material filling the space surrounded by the inner circumferential surface of the frame component and covering the electronic component, and an elastic body fixed around the electronic component on the surface and having a thickness in a direction perpendicular to the surface that is greater than the frame component and the resin material, wherein a space is secured between the elastic body and the frame component. [Effects of the Invention]

[0008] According to this disclosure, it is possible to suppress the loss of elasticity of an elastic body fixed around an electronic component, and to suppress the application of stress from the elastic body to the electronic component. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a top view of a circuit board according to Embodiment 1. [Figure 2] Figure 2 is a cross-sectional view of the circuit board along line AA shown in Figure 1. [Figure 3] Figure 3 is a bottom view of the circuit board. [Figure 4] Figure 4 is a schematic diagram illustrating the action of a sponge. [Figure 5] Figure 5 is a schematic cross-sectional view showing a cross-section of a circuit board according to Embodiment 2. [Figure 6] Figure 6 is a perspective view of the circuit board according to Embodiment 3. [Figure 7] Figure 7 is a perspective view of the circuit board according to Embodiment 4. [Figure 8] Figure 8 is a perspective view of the circuit board according to Embodiment 5. [Modes for carrying out the invention]

[0010] [Description of Embodiments in this Disclosure] First, the embodiments of this disclosure will be listed and described.

[0011] (1) The circuit board according to the present disclosure comprises a printed circuit board, an electronic component mounted on the printed circuit board, a frame component fixed to the surface of the printed circuit board on which the electronic component is mounted and surrounding the electronic component, a resin material filling the space surrounded by the inner circumferential surface of the frame component and covering the electronic component, and an elastic body fixed around the electronic component on the surface and having a thickness in a direction perpendicular to the surface that is greater than the frame component and the resin material, wherein a space is secured between the elastic body and the frame component.

[0012] As shown in paragraphs 0080-0090 and Figure 16 of the aforementioned Patent Document 2, the sensor unit has a temperature sensor surrounded by an elastic member, and molten resin is poured into the space inside the elastic member to form a molded portion. In such a structure, there is a concern that when the molten resin is poured in, the resin will seep into the elastic member, causing the elastic member to harden and impairing its elasticity. If the elasticity of the elastic member is impaired, it becomes difficult to house the sensor unit in a narrow enclosure. In contrast, according to the circuit board described in (1) above, the electronic components are surrounded by frame components, and the space surrounded by the inner circumferential surface of the frame components is filled with resin material, so the resin material does not come into contact with the elastic body. Therefore, it is possible to suppress the resin material from seeping into the elastic body and impairing its elasticity.

[0013] Incidentally, electronic components are generally soldered to circuit boards. If stress is applied to soldered electronic components, the solder may come loose and the electrical contact may be impaired. For this reason, it is undesirable for stress to be applied to soldered electronic components. In the sensor unit described in Patent Document 2 mentioned above, the elastic member is in contact with the molded portion. When the elastic member is elastically compressed, it tends to expand in a direction parallel to the plate surface of the conductive path structure. Therefore, if the elastic member is in contact with the molded portion, there is a concern that stress will be applied to the electronic components due to the force of the elastic member trying to expand in that parallel direction. On the other hand, according to the circuit board described in (1) above, since a space is secured between the elastic body and the frame component, even if the elastic body expands in a direction parallel to the board surface of the printed board, contact with the frame component is suppressed. For this reason, stress being applied from the elastic body to the electronic component can also be suppressed. Therefore, according to the circuit board described in (1) above, it is possible to suppress the loss of the elasticity of the elastic body fixed around the electronic component, and it is possible to suppress stress being applied from the elastic body to the electronic component.

[0014] (2) The circuit board described in (1) above, wherein two of the elastic bodies may be arranged with the frame component interposed therebetween.

[0015] According to the circuit board described in (2) above, since two elastic bodies are arranged with the frame component interposed therebetween, compared to the case where only one of the two elastic bodies is arranged, the back surface of the portion of the circuit board where the electronic component is mounted can be more reliably pressed against the temperature measurement target.

[0016] (3) The circuit board described in (1) above, wherein the elastic body may have a flat plate portion arranged on the side opposite to the printed board with respect to the frame component, and two leg portions extending from both end portions of the flat plate portion to the printed board side and fixed to the surface of the printed board.

[0017] According to the circuit board described in (3) above, since the two leg portions are integrated by the flat plate portion, the number of components can be suppressed compared to the case where the two leg portions are independent. Further, since the two leg portions are integrated by the flat plate portion, the working efficiency of the operation of fixing the elastic body to the printed board is improved compared to the case where the two leg portions are independent.

[0018] (4) The circuit board described in (1) above, wherein the elastic body is in a frame shape and may surround the frame component.

[0019] According to the circuit board described in (4) above, since the electronic components are surrounded by an elastic material, the creepage distance from all directions parallel to the surface of the printed circuit board can be increased. This suppresses the electrical influence that electronic components receive from other electronic components.

[0020] (5) The circuit board described in (1) above, wherein the elastic body has a recess formed on the surface facing the surface, and the frame component is housed in the recess.

[0021] According to the circuit board described in (5) above, since the electronic components are covered with an elastic material, it is possible to more reliably suppress short circuits caused by water droplets formed due to condensation.

[0022] [Details of the embodiments of this disclosure] The embodiments of this disclosure are described below in detail. This disclosure is not limited to these examples, but is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are intended.

[0023] <Embodiment 1> Embodiment 1 will be explained with reference to Figures 1 to 4. In the following explanation, the front-to-back direction and left-to-right direction will be based on the front-to-back direction and left-to-right direction shown in Figure 1, and the up-to-down direction will be based on the up-to-down direction shown in Figure 2.

[0024] [1] Circuit board Referring to Figure 1, the circuit board 1 according to Embodiment 1 will be described. The circuit board 1 is a temperature detection circuit board that is placed on the top, bottom, side, etc. of a predetermined device (an example of a device to be measured for temperature) to detect the temperature of the device.

[0025] The circuit board 1 comprises a flexible printed circuit board 2 (FPC) as a printed circuit board, a thermistor 3 as an electronic component, a frame component 4, a resin material 5 (see Figure 2), a metal plate 6 (see Figure 2) as a plate-shaped component, and two sponges 8 as elastic materials. In the following description, the flexible printed circuit board 2 will be referred to as FPC2.

[0026] [1-1] FPC As shown in Figure 2, the FPC2 comprises a base layer 2A made of a thin insulating material such as a plastic film, a temperature detection line 2B formed by patterning copper foil formed on the base layer 2A, and a coverlay layer 2C made of a thin insulating material. An opening 2D is formed in the coverlay layer 2C where the thermistor 3 is mounted, and the temperature detection line 2B is exposed.

[0027] [1-2] Thermistor Thermistor 3 is an electronic component that detects temperature. A PTC (Positive Temperature Coefficient) thermistor or an NTC (Negative Temperature Coefficient) thermistor can be used. The electrode 3A of thermistor 3 is soldered to the temperature detection line 2B with solder 7. If there are strict height constraints on the circuit board 1, a thin thermistor 3 is preferable.

[0028] [1-3] Frame parts As shown in Figure 1, the frame component 4 is fixed to the surface on which the thermistor 3 is mounted in the FPC 2, and surrounds the thermistor 3. The frame component 4 is rectangular in top view, and has a roughly circular through-hole 4A that penetrates it in the vertical direction (perpendicular to the plane of the paper in Figure 1). The shape of the frame component 4 is not limited to a rectangle, and any suitable shape can be adopted. The shape of the through-hole 4A is also not limited to a roughly circular shape, and any suitable shape can be adopted.

[0029] The frame component 4 is made of an insulating resin material. The frame component 4 is fixed to the FPC2 using double-sided tape or adhesive after the thermistor 3, which is mounted on the FPC2 during the mounting process, is heated and soldered during the reflow process. The reason the frame component 4 is fixed after the reflow process is that, since the frame component 4 is made of resin, there is a risk that it will melt due to the heat of the reflow process if it is fixed before the reflow process.

[0030] As shown in Figure 2, the frame component 4 has a certain thickness. Specifically, the thickness of the frame component 4 (in other words, its width in the vertical direction) is greater than the thickness of the thermistor 3. Therefore, the thermistor 3 is contained within the space 4C surrounded by the inner circumferential surface 4B of the frame component 4. The inner circumferential surface 4B of the frame component 4 according to Embodiment 1 is tapered, with the inner diameter narrowing from the lower side (one side) to the upper side (the other side) in the vertical direction (an example of a direction perpendicular to the surface of the printed circuit board). Therefore, the inner diameter of the inner circumferential surface 4B narrows in the direction away from the FPC2.

[0031] [1-4] Resin materials The resin material 5 is provided to insulate and waterproof the thermistor 3. The resin material 5 is filled (potted) into the space 4C of the frame component 4 and covers the entire thermistor 3. The resin material 5 is, for example, an epoxy resin mixed with a hardening agent that has been cured with ultraviolet light, and has insulating and waterproof properties. The material of the resin material 5 is not limited to epoxy resin; other materials may be used as long as they can be filled into the space 4C and cured, and have insulating and waterproof properties. The resin material 5 is contained within space 4C and does not protrude above space 4C. More specifically, the upper surface 5A of the resin material 5 (in other words, the surface 5A of the resin material 5 opposite to FPC2) is concave towards FPC2.

[0032] [1-5] Sponge As shown in Figures 1 and 2, the two sponges 8 are each rectangular parallelepipeds and are fixed to the surface 2E of the FPC2 on which the thermistor 3 is mounted using adhesive or double-sided tape. The sponges 8 are also fixed after the reflow process. The thickness of the sponge 8 in the direction perpendicular to the surface 2E on which the thermistor 3 of FPC2 is mounted is greater than the thickness of the frame component 4 in that direction.

[0033] Examples of materials for sponge 8 include polyurethane foam, polyester, rubber, and Poron, a product of Inoac Corporation. Sponge 8 comes in various types, including closed-cell foaming (where the air bubbles are independent), continuous-cell foaming (where the air bubbles are continuous), and semi-closed-cell foaming (where several air bubbles are linked together to form one large, independent bubble). Among these, the closed-cell foaming type has the best spring properties (in other words, the largest spring constant), so the closed-cell foaming type of sponge 8 is preferable for pressing the FPC2 against a predetermined device (the object to be measured) with a certain degree of force. Sponge 8 is not limited to the closed-cell foaming type, and an appropriate type can be used depending on the required pressing force.

[0034] Some adhesives do not harden the sponge 8, so it is preferable to use such an adhesive when fixing the sponge 8 with an adhesive. Some versions of Sponge 8 have a skin layer. Sponge 8 with a skin layer is suitable for fixing with double-sided tape.

[0035] [1-6]Metal plate The metal plate 6 (an example of a plate-shaped component) is attached to the back surface of the FPC2 (in other words, the surface 2F opposite to surface 2E on which the thermistor 3 is mounted). The metal plate 6 is made of, for example, copper or aluminum. Specifically, as shown in Figure 3, the metal plate 6 is attached to the area on the back surface of the FPC 2 that includes the area where the thermistor 3 is projected onto the back surface. In the example shown in Figure 3, the metal plate 6 is attached to an area that includes not only the area where the thermistor 3 is projected onto the back surface, but also the area where the frame component 4 is projected onto the back surface, and the area where the sponge 8 is projected onto the back surface. The reason for attaching the metal plate 6 is to provide physical protection for the FPC 2, improve its strength, and improve the temperature measurement accuracy of the thermistor 3.

[0036] [2] The action of a sponge The function of sponge 8 will be explained with reference to Figure 4. The apparatus 10 shown in Figure 4 is the predetermined apparatus (i.e., the apparatus to be measured for temperature) described above. The circuit board 1 is placed on the top surface of apparatus 10 in a position where the side 2F opposite to the side 2E on which the thermistor 3 is mounted is the bottom surface. Another apparatus 11 is placed on the opposite side of apparatus 10 from the circuit board 1, and the circuit board 1 is placed in the narrow gap between apparatus 10 and the other apparatus 11.

[0037] The thickness of the portion of the circuit board 1 to which the frame component 4 is fixed is smaller than the distance between device 10 and other devices 11. In contrast, the thickness of the portion of the circuit board 1 to which the sponge 8 is fixed is larger than that distance. Therefore, the sponge 8 is compressed by device 10 and other devices 11. Because the sponge 8 is elastic, it tries to return to its original thickness when compressed. This reaction force presses the circuit board 1 toward the device 10, thereby improving the temperature measurement accuracy of the thermistor 3.

[0038] As shown in Figure 4, when the sponge 8 is compressed, it expands in the left-right direction. However, as mentioned above, a space is maintained between the sponge 8 and the frame component 4, so even if the sponge 8 expands in the left-right direction, it does not come into contact with the frame component 4. Therefore, the stress acting on the frame component 4 and the thermistor 3 by the sponge 8 expanding in the left-right direction is suppressed. The sponge 8 may be in contact with the frame component 4 to the extent that excessive stress is not applied to the thermistor 3.

[0039] [3] Effects of the embodiment According to the circuit board 1 of Embodiment 1, the thermistor 3 is surrounded by a frame component 4, and the resin material 5 is filled into the space 4C surrounded by the inner circumferential surface of the frame component 4, so that the resin material 5 does not come into contact with the sponge 8. Therefore, it is possible to suppress the resin material 5 from soaking into the sponge 8 and impairing its elasticity. Furthermore, according to the circuit board 1, a space is secured between the sponge 8 and the frame component 4, so even if the sponge 8 expands in a direction parallel to the surface of the FPC 2, contact with the frame component 4 is suppressed. Therefore, stress from the sponge 8 to the thermistor 3 is also suppressed. Therefore, according to the circuit board 1, it is possible to suppress the loss of elasticity of the sponge 8 fixed around the thermistor 3, and also to suppress the application of stress from the sponge 8 to the thermistor 3.

[0040] According to the circuit board 1, two sponges 8 are arranged with a frame component 4 in between. Therefore, compared to the case where only one of the two sponges 8 is arranged, the device 10 can reliably press the back surface of the part of the circuit board 1 on which the thermistor 3 is mounted.

[0041] <Embodiment 2> Referring to Figure 5, the circuit board 201 according to Embodiment 2 will be described. The inner circumferential surface 204B of the frame component 204 of the circuit board 201 is tapered, with the inner diameter narrowing from the upper side (one example) to the lower side (an example) in the vertical direction (an example of a direction perpendicular to the board surface of the printed circuit board). Therefore, the inner diameter of the inner circumferential surface 204B narrows toward the FPC2. In this way, the inner circumferential surface 204B of the frame component 204 is held in place by the resin material 5, making it difficult for the frame component 204 to come off.

[0042] <Embodiment 3> Referring to Figure 6, the circuit board 301 according to Embodiment 3 will be described. The sponge 308 according to Embodiment 3 has a flat plate-shaped portion 308A that is positioned on the opposite side from the FPC2 with respect to the frame component 4, and two leg portions 308B that extend from both ends of the flat plate-shaped portion 308A toward the FPC2 and are fixed to the surface of the FPC2 (the surface on which the thermistor 3 is mounted). The two leg portions 308B are each rectangular in shape when viewed from above.

[0043] According to the circuit board 1 of Embodiment 3, since the two legs 308B are integrated by the flat plate portion 308A, the number of components can be reduced compared to the case where the two legs 308B are independent. Furthermore, since the two legs 308B are integrated by the flat plate portion 308A, the work efficiency of fixing the sponge 8 to the FPC 2 is improved compared to the case where the two legs 308B are independent.

[0044] <Embodiment 4> Referring to Figure 7, the circuit board 401 according to Embodiment 4 will be described. The sponge 408 according to Embodiment 4 is frame-shaped and surrounds the frame component 4. Specifically, the sponge 8 is rectangular in top view and has a substantially rectangular through-hole 408A that penetrates in the vertical direction.

[0045] According to the circuit board 401 of Embodiment 4, the thermistor 3 is surrounded by the sponge 408, which increases the creepage distance from all directions parallel to the surface of the FPC 2. This suppresses the thermistor 3 from being electrically affected by other electronic components.

[0046] <Embodiment 5> Referring to Figure 7, the circuit board 501 according to Embodiment 5 will be described. In the sponge 508 according to Embodiment 5, a recess 508A is formed on the side facing the surface on which the thermistor 3 is mounted in the FPC 2, and the frame component 4 is housed in the recess 508A. Specifically, the sponge 8 is rectangular in shape when viewed from above. The recess 508A is also rectangular in shape when viewed from above.

[0047] According to the circuit board 1 of Embodiment 5, the thermistor 3 is covered by the sponge 508, so that the thermistor 3 can be more reliably prevented from short-circuiting due to water droplets formed due to condensation.

[0048] <Other Embodiments> The technology disclosed herein is not limited to the embodiments described above in the description and drawings, and the following embodiments, for example, are also included in the technical scope disclosed herein.

[0049] (1) In the above embodiment, thermistor 3 was used as an example of an electronic component, but the electronic component is not limited to thermistor 3 and may be other electronic components. For example, the electronic component may be a chip fuse.

[0050] (2) In Embodiment 1 above, the example shown was that the sponge 8 is a rectangular parallelepiped, but the shape of the sponge 8 is not limited to a rectangular parallelepiped, and any suitable shape can be adopted. For example, the sponge 8 may be circular, elliptical, or triangular when viewed from above.

[0051] (3) In the above embodiment 3, the case in which the leg portion 308B of the sponge 308 is rectangular in shape when viewed from above was illustrated, but the shape of the leg portion 308B is not limited to rectangular, and any suitable shape can be adopted. For example, the leg portion 308B may be circular, elliptical, or triangular when viewed from above.

[0052] (4) In the above embodiment 4, the sponge 408 is rectangular in shape when viewed from above, and a substantially rectangular through hole 408A that penetrates in the vertical direction is provided as an example, but the shape of the sponge 408 is not limited to this. For example, the sponge 408 may be circular, elliptical, or triangular when viewed from above. The shape of the through hole 408A is not limited to a rectangular shape, but may also be circular, elliptical, or triangular. If the sponge 408 is circular when viewed from above, and the through hole 408A is also circular, there are no constraints on the rotation angle of the sponge 408 around a virtual axis perpendicular to the surface of the FPC2. This eliminates the need for angle adjustment and improves the workability of fixing the sponge 408.

[0053] (5) In Embodiment 5 described above, the sponge 508 is rectangular in shape when viewed from above, and the recess 508A is also rectangular in shape when viewed from above. However, the shape of the sponge 508 is not limited to this. For example, the sponge 508 may be circular or elliptical when viewed from above. The shape of the recess is not limited to a rectangular shape, and may be circular or elliptical.

[0054] (6) In the above embodiment, sponge 8 was used as an example of the elastic body, but the elastic body may be synthetic rubber or silicone rubber. Alternatively, the elastic body may be a resin spring or a metal spring. From the viewpoint of insulation, a resin spring is preferable to a metal spring. When the height limit for circuit board 1 is strict (when the height H shown in Figure 4 is narrow), sponge 8 is preferred as the elastic material. This is because it is difficult to ensure sufficient springiness in a narrow space with materials such as silicone rubber or resin springs. In contrast, with sponge 8, for example, by using a closed-cell foam type, it is easier to ensure sufficient springiness even in a narrow space.

[0055] (7) In the above embodiment, the case in which the resin material 5 is contained within space 4C was illustrated. In contrast, if, for example, there are no strict constraints on the height dimension of the circuit board 1 and only the spread dimension of the resin material 5 needs to be controlled, the resin material 5 may protrude above space 4C.

[0056] (8) In the above embodiment, the upper surface 5A of the resin material 5 was shown as a concave shape, but the upper surface 5A does not have to be concave as long as the resin material 5 does not protrude above the space 4C. For example, the upper surface 5A may be a flat surface that is flush with the upper surface of the frame component 4.

[0057] (9) In the above embodiment, the resin material 5 was shown as having insulating and waterproof properties, but the resin material 5 may have only one of these properties. For example, if the circuit board 1 is located in a place where the possibility of short circuits is low, the resin material 5 does not need to have insulating properties. Alternatively, if the circuit board 1 is located in a place that is completely sealed and where condensation is unlikely to occur, the resin material 5 does not need to have waterproof properties.

[0058] (10) In the above embodiment, the case in which the inner circumferential surface 4B of the frame component 4 is tapered was illustrated, but the inner circumferential surface 4B does not have to be tapered. That is, the inner diameter of the inner circumferential surface 4B of the frame component 4 may be constant from top to bottom.

[0059] (11) In the above embodiment, the case in which the frame component 4 is made of resin was illustrated, but even if the frame component 4 is made of metal, if the possibility of the circuit board 1 short-circuiting is low, the frame component 4 may be made of metal. However, in order to reliably protect the circuit board 1 from short-circuiting, it is preferable that the frame component 4 be made of resin.

[0060] (12) In the above embodiment, the case in which a metal plate 6 is attached to the back surface of the FPC2 was illustrated, but the metal plate 6 does not have to be attached.

[0061] (13) In the above embodiment, a metal plate 6 was used as an example of a plate-shaped part, but the material of the plate-shaped part is not limited to metal, and may be resin.

[0062] (14) In the above embodiment, FPC2 was used as an example of a printed circuit board, but the printed circuit board may be a rigid printed circuit board (a so-called rigid substrate). Examples of rigid substrates include a so-called glass epoxy substrate made by impregnating glass fibers with epoxy resin, a glass substrate using glass as the base material, an aluminum substrate using aluminum as the base material, and a copper substrate using copper as the base material.

[0063] (15) As mentioned above, the shape of the through hole 4A of the frame component 4 is not limited to a roughly circular shape, and any suitable shape can be adopted. For example, the through hole 4A may be square, rectangular, elliptical, or triangular. The shape of the through-hole 4A may be one that closely matches the shape of the electronic component. For example, if the electronic component is rectangular, making the through-hole 4A rectangular will allow the distance between the electronic component and the inner surface of the through-hole 4A to be roughly constant around the entire circumference of the electronic component. In this way, the creepage distance from any point a certain distance away from the electronic component to the electronic component can be made roughly constant. [Explanation of Symbols]

[0064] 1: Circuit board 2: FPC (an example of a printed circuit board) 2A: Base layer 2B: Temperature detection line 2C: Coverlay layer 2D: Opening 2E: Surface (an example of a surface on which electronic components are mounted) 2F: Side (the side opposite to the side on which electronic components are mounted) 3: Thermistor (an example of an electronic component) 3A: Electrode 4: Frame parts 4A: Through hole 4B: Inner surface 4C: Space 5: Resin material 5A: Top 6: Metal plate 7: Handa 8: Sponge (an example of an elastic material) 10: Equipment 11: Equipment 201: Circuit board 204: Frame parts 204B: Inner surface 301: Circuit board 308: Sponge (an example of an elastic material) 308A: Flat part 308B: Legs 401: Circuit board 408: Sponge (an example of an elastic material) 408A: Through hole 501: Circuit board 508: Sponge (an example of an elastic material) 508A: Recess H: Height

Claims

1. Printed circuit board and The electronic components mounted on the aforementioned printed circuit board, A frame component is fixed to the surface of the printed circuit board on which the electronic components are mounted, and surrounds the electronic components. A resin material that fills the space surrounded by the inner circumferential surface of the frame component and covers the electronic component, An elastic body is fixed around the electronic component on the aforementioned surface, and its thickness in a direction perpendicular to the said surface is greater than that of the frame component and the resin material. Equipped with, A circuit board in which a space is secured between the elastic body and the frame component.

2. A circuit board according to claim 1, A circuit board in which two of the elastic bodies are arranged with the aforementioned frame component in between.

3. A circuit board according to claim 1, The elastic body is a circuit board having a flat plate-shaped portion positioned on the opposite side of the printed circuit board with respect to the frame component, and two leg portions extending from both ends of the flat plate-shaped portion toward the printed circuit board and fixed to the surface of the printed circuit board.

4. A circuit board according to claim 1, The elastic body is frame-shaped and surrounds the frame component; this is a circuit board.

5. A circuit board according to claim 1, The elastic body has a recess formed on the surface facing the aforementioned side, and the frame component is housed in the recess, wherein the circuit board.

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