Electronic device

Abstract

To provide an electronic device capable of suppressing defects caused by substrate scraps.SOLUTION: A board pressing portion 41 of an elastic member 40 is compressed between an upper case 22 and a printed board 31, and the printed board 31 is pressed against a pedestal 212 of a lower case 21 from the upper surface 31b side by the reaction force of the elastic deformation, such that the printed board 31 is supported, and a conductor pattern 312 is brought into contact with a lower projection 213 to be electrically connected to the lower case 21. A holding portion 42 has an annular shape surrounding the lower projection 213, and the inner peripheral end is in close contact with the entire side surface of the lower projection 213, and is in close contact with the lower surface 31a of the printed board 31 so as to continuously surround the pedestal 212 and the conductor pattern 312.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The disclosure in this specification relates to an electronic device.

Background Art

[0002] Patent Document 1 discloses an electronic device in which a printed circuit board is housed in a housing. In this electronic device, an elastic member made of a columnar rubber material is assembled to the upper case of the housing, and the printed circuit board is supported by pressing the printed circuit board against the pedestal of the lower case from the upper surface side by the reaction force of the elastic deformation of the elastic member. The description of the prior art document is incorporated herein by reference as an explanation of the technical elements in this specification.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the electronic device having the above structure, a conductor pattern is provided on the lower surface of the printed circuit board, and the conductor pattern can be electrically connected to, that is, grounded to, the conductive lower case by using the reaction force of the elastic member.

[0005] However, due to expansion and contraction caused by changes in the use environment temperature, vibration transmitted from the outside, etc., the printed circuit board may slide relative to the lower case, and there is a risk of generating board chips. In particular, when metal chips derived from the conductor pattern are generated, there is a risk of circuit short circuit or the like. From the above viewpoints, or from other viewpoints not mentioned, further improvements are required for the electronic device.

[0006] One object of the disclosure is to provide an electronic device capable of suppressing problems caused by board chips.

Means for Solving the Problems

[0007] The electronic device disclosed herein a printed circuit board (31) having a through hole (311) that opens to the lower surface (31a) and the upper surface (31b), and a conductor pattern (312) provided around the opening of the through hole on the lower surface; a conductive lower case (21) having a pedestal (212) on which the printed circuit board is mounted and a lower protrusion (213) protruding from the front end surface of the pedestal, and being disposed on the lower surface side of the printed circuit board; an upper case (22) disposed on the upper surface side of the printed circuit board and providing an accommodation space for the printed circuit board together with the lower case; a board pressing portion (41) that is compressed between the upper case and the printed circuit board and presses the printed circuit board against the pedestal from the upper surface side by the reaction force of elastic deformation, thereby supporting the printed circuit board and bringing the conductor pattern into contact with the lower protrusion to electrically connect to the lower case; a holding portion (42) that forms an annular shape surrounding the lower protrusion, the inner peripheral end of which is in close contact with the entire circumference of the side surface of the lower protrusion and is in close contact with the lower surface of the printed circuit board so as to continuously surround the pedestal, the lower protrusion, and the conductor pattern; and a connecting portion (43) that connects the board pressing portion and the holding portion and at least a part of which is disposed in the through hole; an elastic member (40) having the above; is provided.

[0008] According to the disclosed electronic device, even if the printed circuit board slides relative to the lower case due to a change in the use environment temperature or vibration transmitted from the outside, and substrate chips are generated, the substrate chips can be held by the holding portion of the elastic member. As a result, it is possible to provide an electronic device that can suppress problems caused by substrate chips.

[0009] The disclosed embodiments in this specification adopt different technical means to achieve their respective purposes. The claims and the reference numerals in parentheses described in this section exemplarily show the correspondence with the parts of the embodiments described later, and are not intended to limit the technical scope. The purposes, features, and effects disclosed in this specification will become clearer by referring to the subsequent detailed description and the accompanying drawings.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

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Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Best Mode for Carrying Out the Invention

[0011] Hereinafter, a plurality of embodiments will be described with reference to the drawings. In the plurality of embodiments, parts that are functionally and / or structurally corresponding and / or associated may be given the same reference numerals. For the corresponding parts and / or the associated parts, the description of other embodiments can be referred to. When only a part of the configuration is described in each embodiment, for the other parts of the said configuration, the configuration of other embodiments described previously can be applied. Also, not only the combinations of the configurations explicitly shown in the description of each embodiment, but also the configurations of the plurality of embodiments can be partially combined with each other as long as there is no problem with the combination, even if not explicitly shown.

[0012] (First Embodiment) First, the schematic configuration of the electronic device will be described.

[0013] <Electronic Device> Hereinafter, the thickness direction of the printed circuit board is shown as the Z direction. Also, one direction orthogonal to the Z direction is shown as the X direction, and the direction orthogonal to both the Z direction and the X direction is shown as the Y direction. Unless otherwise specified, the shape viewed in plan from the Z direction, in other words, the shape along the XY plane defined by the X direction and the Y direction, is taken as the planar shape. The plan view from the Z direction may be simply shown as a plan view.

[0014] FIG. 1 is a perspective view showing the electronic device 10. In FIG. 1, for the sake of convenience, the structures such as the housing and the connector are simplified, and the fixing screws and the like are omitted from the illustration. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1. As shown in FIGS. 1 and 2, the electronic device 10 includes a housing 20, a circuit board 30, and an elastic member 40. The electronic device 10 is, for example, an electronic control unit (ECU) that controls an actuator mounted on a vehicle. ECU is an abbreviation for Electronic Control Unit.

[0015] <Housing> FIG. 3 is a view showing the periphery of the pedestal of the lower case. FIG. 3(a) is a plan view of the bottom wall seen from the inner surface side, and FIG. 3(b) is a side view of FIG. 3(a) seen from the B3 direction. FIG. 4 is a view showing the periphery of the upper protrusion of the upper case. FIG. 4(a) is a plan view of the bottom wall seen from the inner surface side, and FIG. 4(b) is a side view of FIG. 4(a) seen from the B4 direction.

[0016] The housing 20 houses at least a part of other elements of the electronic device 10. The housing 20 provides a housing space 20S. The housing 20 is formed by assembling a plurality of members. The housing 20 is configured to be dividable into two parts in the Z direction. The housing 20 includes a lower case 21 and an upper case 22. The lower case 21 is mainly disposed on the lower surface 31a side of a printed circuit board 31 described later. The upper case 22 is mainly disposed on the upper surface 31b side of the printed circuit board 31.

[0017] The lower case 21 has a box shape with one side open. At least a part of the bottom wall 211 of the lower case 21 faces the lower surface 31a of the printed circuit board 31. The upper case 22 also has a box shape with one side open. At least a part of the bottom wall 221 of the upper case 22 faces the upper surface 31b of the printed circuit board 31. By assembling the lower case 21 and the upper case 22 so that the opening surfaces face each other, the housing 20 having the housing space 20S is configured. In the present embodiment, the lower case 21 and the upper case 22 are fastened and fixed. The lower case 21 and the upper case 22 have flange portions at both ends in the X direction. The fixing portions using the screws 23 are provided on the flange portions. The fixing portions are provided, for example, at two locations at both ends in the X direction.

[0018] The lower case 21 has conductivity. The lower case 21 is electrically connected to a vehicle ground such as a chassis. The lower case 21 is formed using a metal material. The lower case 21 may be, for example, an integrally formed metal molded body (such as an aluminum die-cast), or may be one with conductivity imparted by forming a metal plating film or the like on a resin molded body. In the present embodiment, a metal molded body, that is, a metal lower case 21 is employed. The lower case 21 can function as, for example, a heat dissipation member and an electromagnetic shield. The upper case 22 may be formed using a resin material or may be formed using a metal material. The upper case 22 of the present embodiment is formed using a resin material.

[0019] As shown in FIGS. 2 and 3, the lower case 21 has a pedestal 212 protruding from the inner surface of the bottom wall 211. The pedestal 212 is a portion of the lower case 21 where the circuit board 30 (printed circuit board 31) is mounted. The pedestal 212 extends in the Z direction from the bottom wall 211. The planar shape of the pedestal 212 is not particularly limited. The pedestal 212 of the present embodiment has a substantially circular planar shape. The pedestal 212 has a substantially cylindrical shape. The tip surface (upper surface) of the pedestal 212 is a flat surface substantially orthogonal to the Z direction.

[0020] The lower case 21 has a lower protrusion 213. The lower protrusion 213 is a protrusion provided on the lower case 21 for electrical connection with a conductor pattern 312 described later. The lower protrusion 213 is provided on a part of the tip surface of the pedestal 212 to provide a contact point with the conductor pattern 312. The lower protrusion 213 protrudes from the tip surface of the pedestal 212. The lower protrusion 213 extends in the Z direction from the pedestal 212. The lower protrusion 213 is continuously connected to the pedestal 212.

[0021] The lower protrusion 213 of the present embodiment is linear and substantially parallel to the Y direction in a plan view, and is provided so as to overlap with the center of the circle of the pedestal 212. The lower protrusion 213 is provided so as to bisect the protruding front end surface of the pedestal 212. The protruding front end surface of the lower protrusion 213 is a flat surface that is substantially orthogonal to the Z direction. Among the side surfaces of the lower protrusion 213, the side surface in the X direction is a flat surface that is substantially orthogonal to the X direction, and the side surface in the Y direction is an arc-shaped surface obtained by extending the side surface shape of the pedestal 212 in the Z direction. The length of the lower protrusion 213 in the X direction, that is, the width, is substantially constant.

[0022] As shown in FIGS. 2 and 4, the upper case 22 has an upper protrusion 222 that protrudes from the inner surface of the bottom wall 221. The upper protrusion 222 is a protrusion provided on the upper case 22 for assembling (fixing) the elastic member 40. The upper protrusion 222 extends in the Z direction from the bottom wall 221. The upper protrusion 222 of the present embodiment has a frustum shape. The protruding front end surface of the upper protrusion 222 is a flat surface that is substantially orthogonal to the Z direction. The upper protrusion 222 is provided at a position that overlaps with the pedestal 212 in a plan view. The upper protrusion 222 is provided at a position that overlaps with a part of the lower protrusion 213 in a plan view.

[0023] The pedestal 212, the lower protrusion 213, and the upper protrusion 222 are provided at four locations in the housing 20. For example, they are provided at two locations on each side in the X direction.

[0024] <Circuit board> FIG. 5 is a plan view showing the periphery of the conductor pattern of the printed circuit board. FIG. 6 is a plan view showing the positional relationship between the lower protrusion 213 and the conductor pattern. In FIG. 6, the pedestal 212 is shown by a broken line. Also, for clarity, hatching is applied to the contact 213a of the lower protrusion 213.

[0025] As shown in FIGS. 2 and 5, the circuit board 30 includes a printed circuit board 31 and electronic components 32. The printed circuit board 31 may be referred to as a substrate, a wiring board, or the like. The printed circuit board 31 has a lower surface 31a and an upper surface 31b which is opposite to the lower surface 31a in the plate thickness direction (Z direction). The planar shape of the printed circuit board 31 is, for example, substantially rectangular.

[0026] The printed circuit board 31 is formed by arranging conductors on a base material formed using an electrically insulating material such as resin. The conductors, together with the electronic components 32, constitute a circuit. The conductors are formed using a metal material with good conductivity such as Cu. The conductors at least include wirings. The wirings are formed, for example, by patterning metal foils. The conductors may include via conductors in addition to the wirings. The via conductors are formed by arranging conductors such as plating in through holes (vias) formed in the insulating layer constituting the base material. The via conductors electrically connect the wirings arranged in different layers.

[0027] The wirings at least include surface layer wirings arranged on the surface layer on the lower surface 31a side with respect to the base material. The wirings may include surface layer wirings arranged on the surface layer on the upper surface 31b side, or may include inner layer wirings arranged inside the base material. The wirings in this embodiment are arranged in multiple layers with respect to the base material. That is, the printed circuit board 31 is a multilayer board.

[0028] As shown in FIGS. 2, 5, and 6, the printed circuit board 31 has through holes 311 and conductor patterns 312. The through holes 311 extend in the Z direction and open to the lower surface 31a and the upper surface 31b. Through these through holes 311, the elastic members 40 are arranged on the lower surface 31a side and the upper surface 31b side of the printed circuit board 31. The through holes 311 are provided so as to overlap the pedestal 212 in plan view. The through holes 311 are provided so as to overlap at least a part of the lower protrusion 213 and at least a part of the upper protrusion 222 in plan view.

[0029] The conductor pattern 312 is a wiring electrically connected to the lower case 21. The conductor pattern 312 is electrically connected to the vehicle ground via the metal part of the housing 20. The conductor pattern 312 is a land of a ground pattern (substrate ground) (not shown) provided on the printed circuit board 31. The conductor pattern 312 is provided around the opening of the through hole 311 on the lower surface 31a of the printed circuit board 31. The conductor pattern 312 of the present embodiment has a substantially planar annular shape surrounding the through hole 311. Instead of the substantially annular shape, a substantially C-shaped or the like may be adopted.

[0030] The conductor pattern 312 is provided so as to overlap at least a part of the pedestal 212 and at least a part of the lower protrusion 213 in a plan view. The conductor pattern 312 of the present embodiment overlaps the outer contour of the front end surface of the pedestal 212 in its entirety and is provided so as to overlap both end portions of the lower protrusion 213 in the Y direction. The conductor pattern 312 is in contact with the lower protrusion 213 by the reaction force of the elastic deformation of the elastic member 40 described later and is electrically connected to the lower case 21. Among the lower protrusions 213, the contact portion with the conductor pattern 312 functions as a contact point 213a which is an electrical connection point. In the present embodiment, among the lower protrusions 213, both end portions in the Y direction that overlap the conductor pattern 312 in a plan view function as the contact point 213a.

[0031] The electronic component 32 is mounted on the printed circuit board 31. As described above, the electronic component 32 constitutes a circuit together with the conductors of the printed circuit board 31. The electronic device 10 of the present embodiment includes a plurality of electronic components 32. The electronic components 32 are arranged on the lower surface 31a and the upper surface 31b of the printed circuit board 31 respectively. The electronic components 32 are electrically connected to wirings (not shown) of the printed circuit board 31.

[0032] The connector 33 shown in FIG. 1 is mounted on the circuit board 30. The connector 33 electrically connects the circuit board 30 and an external device. A part of the connector 33 is housed inside the housing 20, and the other part is exposed outside the housing 20 as shown in FIG. 1. The housing 20 has an opening 201 for exposing the connector 33 to the outside.

[0033] <Elastic member> FIG. 7 is a view showing the elastic member 40. FIG. 7(a) is a plan view seen from the Z direction. FIG. 7(b) is a side view of FIG. 7(a) seen from the B7 direction, and FIG. 7(c) is a cross-sectional view taken along the C7-C7 line of FIG. 7(a). FIG. 8 is a cross-sectional view showing the support structure of the printed circuit board 31 by the elastic member 40. FIG. 8 is an enlarged view of the periphery of the elastic member 40 in FIG. 2. FIG. 9 is a cross-sectional view taken along the IX-IX line of FIG. 8.

[0034] The elastic member 40 is formed of rubber as a material. The elastic member 40 is a rubber molded body. The electronic device 10 includes the same number of elastic members 40 as the lower protrusions 213 and the upper protrusions 222. The electronic device 10 of the present embodiment includes four elastic members 40.

[0035] The elastic member 40 supports the printed circuit board 31 by the reaction force due to elastic deformation. Due to this reaction force, the elastic member 40 electrically connects, that is, grounds the conductor pattern 312 to the lower case 21. The elastic member 40 holds the substrate chips generated by the sliding between the lower case 21 and the printed circuit board 31. The elastic member 40 is configured to exhibit these functions. The elastic member 40 of the present embodiment has a substrate pressing portion 41, a holding portion 42, a connecting portion 43, and a recess 44 as shown in FIGS. 7, 8, and 9.

[0036] The substrate pressing portion 41 is mainly disposed on the upper surface 31b side of the printed circuit board 31 in the Z direction. The substrate pressing portion 41 contacts the upper surface 31b of the printed circuit board 31 when the upper case 22 is assembled (fastened) to the lower case 21. Here, the upper surface 31b includes the corner portion with the wall surface of the through hole 311, that is, the opening end of the through hole 311. The substrate pressing portion 41 is compressed and elastically deformed between the upper case 22 and the upper surface 31b of the printed circuit board 31 in the Z direction.

[0037] The substrate pressing portion 41 applies a reaction force due to elastic deformation to the printed circuit board 31 from the upper surface 31b side, and presses the printed circuit board 31 against the pedestal 212. The reaction force of the elastic deformation includes a component in the Z direction and directed from the upper case 22 side toward the lower case 21 side. By this pressing, the elastic member 40 supports the printed circuit board 31. Also, by the pressing, the contact point 213a of the lower protrusion 213 contacts the conductor pattern 312, and the conductor pattern 312 is electrically connected to the lower case 21, that is, grounded.

[0038] The substrate pressing portion 41 has an upper case fixing portion 411 for fixing the elastic member 40 to the upper case 22. The upper case fixing portion 411 provides an accommodation space for the upper protrusion 222. This accommodation space opens in the Z direction and on the upper case 22 side. The upper case fixing portion 411 has a tapered wall surface corresponding to the frustum-shaped upper protrusion 222. When the upper protrusion 222 is inserted into the accommodation space, the substrate pressing portion 41 is pushed by the upper protrusion 222 and elastically deformed, and expands in the X direction. Thereby, the substrate pressing portion 41 becomes easier to contact the upper surface 31b of the printed circuit board 31. That is, it becomes easier for the substrate pressing portion 41 to press the printed circuit board 31.

[0039] The holding portion 42 is mainly disposed on the lower surface 31a side of the printed circuit board 31 in the Z direction. The holding portion 42 holds substrate chips. The holding portion 42 forms an annular shape so as to surround the lower protrusion 213. The inner peripheral end of the holding portion 42 is in close contact with the entire circumference of the side surface of the lower protrusion 213. The holding portion 42 is in close contact with the lower surface 31a of the printed circuit board 31 so as to continuously surround the pedestal 212, the lower protrusion 213, and the conductor pattern 312 in plan view. Due to these close contact structures, the holding portion 42 holds the substrate chips generated by the sliding between the lower case 21 (lower protrusion 213) and the printed circuit board 31.

[0040] The holding part 42 of this embodiment has an umbrella shape. The umbrella shape may be referred to as a suction cup shape. The holding part 42 has an annular shape in plan view. The holding part 42 has a lower case fixing part 421 for fixing the elastic member 40 to the lower case 21. The lower case fixing part 421 provides a housing space for the lower protrusion 213. This housing space opens on the side of the lower case 21 in the Z direction. The inner peripheral end of the holding part 42 constitutes the annular side wall of the lower case fixing part 421. The lower case fixing part 421 has a substantially rectangular shape with the Y direction as the longitudinal direction in plan view. In order to enhance the adhesion to the side surface of the lower protrusion 213, both ends in the Y direction may be arc-shaped. When the lower protrusion 213 is inserted into the housing space, the holding part 42 elastically deforms, and the inner peripheral end of the holding part 42 adheres to the entire circumference of the side surface of the lower protrusion 213.

[0041] As shown in FIG. 7(c), in the state before elastic deformation, the umbrella-shaped holding part 42 has a shape in which, in the radial direction, as it approaches the outer peripheral end, it moves away from the inner peripheral end in the Z direction. The outer peripheral end of the holding part 42 is located at least above the inner peripheral end. In this embodiment, in the state before elastic deformation, the outer peripheral end of the holding part 42 is located above the upper end of the recess 44 described later. The thickness of the holding part 42 gradually decreases from the inner peripheral end toward the outer peripheral end.

[0042] When the upper case 22 is assembled to the lower case 21, when the printed circuit board 31 is pressed against the pedestal 212 side, the holding part 42 is elastically deformed while being sandwiched between the front end surface of the pedestal 212 and the lower surface 31a of the printed circuit board 31. Due to the reaction force of the elastic deformation, the holding part 42 adheres to the lower surface 31a of the printed circuit board 31. The vicinity of the outer peripheral end of the umbrella-shaped holding part 42 adheres to the lower surface 31a over the entire circumference. The contact part 422 of the holding part 42 with the lower surface 31a continuously surrounds the pedestal 212, the lower protrusion 213, and the conductor pattern 312 in plan view. Also, the holding part 42 adheres to the front end surface of the pedestal 212.

[0043] The connecting portion 43 connects the substrate pressing portion 41 and the holding portion 42. At least a part of the connecting portion 43 is disposed in the through hole 311 of the printed circuit board 31. That is, the elastic member 40 passes through the through hole 311, the substrate pressing portion 41 is disposed on the upper surface 31b side, and the holding portion 42 is disposed on the lower surface 31a side. The connecting portion 43 has a space communicating with the accommodation space of the upper case fixing portion 411 and the accommodation space of the lower case fixing portion 421.

[0044] In the present embodiment, the substrate pressing portion 41 and the connecting portion 43 are constituted by two columnar portions 45, 46. The two columnar portions 45, 46 extend from the inner peripheral end of the holding portion 42 in the Z direction toward the upper case 22 side. The two columnar portions 45, 46 have a structure in which a cylindrical shape is divided into two. The columnar portions 45, 46 are disposed opposite to each other in the X direction.

[0045] The connecting portion 43 may form a part of the lower case fixing portion 421. The connecting portion 43 of the present embodiment forms the bottom wall that defines the accommodation space of the lower case fixing portion 421. Similarly, the connecting portion 43 may form a part of the upper case fixing portion 411.

[0046] The recess 44 is provided from the substrate pressing portion 41 to the connecting portion 43. The recess 44 is provided on the outer surface opposite to the facing surface in the columnar portions 45, 46. The upper end of the recess 44 is located above the upper surface 31b of the printed circuit board 31. Thereby, the printed circuit board 31 is caught in the recess 44 during assembly, and the substrate pressing portion 41 easily contacts the upper surface 31b of the printed circuit board 31. In the present embodiment, the lower end of the recess 44 substantially coincides with the lower end of the connecting portion 43.

[0047] <Assembly method of elastic member> Next, a method for assembling the elastic member 40 will be described. FIGS. 10, 11, and 12 are side views showing a method for assembling the elastic member 40. FIGS. 10 to 12 correspond to FIGS. 3(b), 4(b), and 7(b).

[0048] First, as shown in FIG. 10, fix the elastic member 40 to the lower case 21. Position the elastic member 40 with respect to the pedestal 212 and the lower protrusion 213, and insert the lower protrusion 213 into the accommodation space of the lower case fixing portion 421 of the holding portion 42. As a result, the holding portion 42 is elastically deformed and adheres to the entire circumference of the side surface of the lower protrusion 213.

[0049] Next, as shown in FIG. 11, arrange the printed circuit board 31 (circuit board 30). At this time, elastically deform the elastic member 40 and insert it into the through hole 311 from the substrate pressing portion 41 side. At least a part of the substrate pressing portion 41 passes through the through hole 311 and is located on the upper surface 31b side. The outer peripheral end of the holding portion 42 contacts the lower surface 31a of the printed circuit board 31.

[0050] Next, as shown in FIG. 12, fix the elastic member 40 to the upper case 22. Specifically, assemble the upper case 22 to the lower case 21 and fix the elastic member 40 to the upper case 22. By bringing the upper case 22 closer to the lower case 21, insert the upper protrusion 222 into the accommodation space of the upper case fixing portion 411. The substrate pressing portion 41 is elastically deformed between the upper case 22 and the printed circuit board 31, and presses the printed circuit board 31 against the pedestal 212 by the reaction force of the elastic deformation. Also, the holding portion 42 is elastically deformed between the printed circuit board 31 and the pedestal 212.

[0051] <Summary of the First Embodiment> In this embodiment, the substrate pressing portion 41 of the elastic member 40 is compressed between the upper case 22 and the printed circuit board 31, and presses the printed circuit board 31 against the pedestal 212 from the upper surface 31b side by the reaction force of the elastic deformation. Thereby, the printed circuit board 31 can be supported. Also, the conductor pattern 312 can be brought into contact with the lower protrusion 213 to be electrically connected to the lower case 21, that is, grounded.

[0052] Further, a through-hole 311 is formed in the printed circuit board 31, and the elastic member 40 is inserted through the through-hole 311. Through the through-hole 311, a holding portion 42 which is a part of the elastic member 40 is disposed on the lower surface 31a side of the printed circuit board 31. The holding portion 42 has an annular shape surrounding the lower protrusion 213 in a plan view. The inner peripheral end of the holding portion 42 is in close contact with the side surface of the lower protrusion 213 over the entire circumference. Further, the holding portion 42 is in close contact with the lower surface 31a of the printed circuit board 31 at a position away from the inner peripheral end so as to continuously surround the pedestal 212, the lower protrusion 213, and the conductor pattern 312 in a plan view. Particularly in the present embodiment, the outer peripheral end portion of the umbrella-shaped holding portion 42 is in close contact with the lower surface 31a over the entire circumference.

[0053] Due to expansion and contraction caused by changes in the use environment temperature, vibration transmitted from the outside, etc., the printed circuit board 31 slides relative to the lower case 21. Even if substrate debris is generated due to this sliding, the above-described close contact structure of the holding portion 42 can hold the substrate debris. Specifically, in the accommodation space 20S, scattering of the substrate debris to the region on the lower surface 31a side can be suppressed. Further, the connecting portion 43 disposed in the through-hole 311 can suppress scattering of the substrate debris to the region on the upper surface 31b side through the through-hole 311. Furthermore, the substrate pressing portion 41 that contacts the upper surface 31b of the printed circuit board can suppress scattering of the substrate debris to the region on the upper surface 31b side. From the above, it is possible to suppress the occurrence of problems due to substrate debris. Even if metal debris derived from the conductor pattern 312 is generated as the substrate debris, it is possible to suppress the occurrence of problems such as a short circuit in the circuit.

[0054] In the present embodiment, the electronic component 32 is disposed on the lower surface 31a of the printed circuit board 31. The above-described holding portion 42 suppresses scattering of the substrate debris to the region on the lower surface 31a side of the accommodation space 20S. Therefore, it is possible to effectively suppress the occurrence of problems due to substrate debris on the lower surface 31a side.

[0055] In this embodiment, the holding portion 42 has an umbrella shape (suction cup shape). Therefore, the outer peripheral end of the holding portion 42 is firmly adhered to the lower surface 31a over the entire circumference. The adhesion portion 422 between the outer peripheral end and the lower surface 31a continuously surrounds the pedestal 212, the lower protrusion 213, and the conductor pattern 312 in a plan view. Thus, it is possible to effectively suppress the scattering of substrate chips to the region on the lower surface 31a side of the accommodation space 20S.

[0056] In this embodiment, the upper case 22 has an upper protrusion 222. The substrate pressing portion 41 has an upper case fixing portion 411 that houses the upper protrusion 222. When the upper protrusion 222 is inserted into the accommodation space, the substrate pressing portion 41 is pushed by the upper protrusion 222 and elastically deformed, expanding in the X direction. As a result, it becomes easier for the substrate pressing portion 41 to press the printed circuit board 31. For example, the substrate pressing portion 41 becomes more likely to contact the upper surface 31b of the printed circuit board 31. For example, it is possible to increase the contact area between the substrate pressing portion 41 and the upper surface 31b.

[0057] In this embodiment, the elastic member 40 has a recess 44 provided from the substrate pressing portion 41 to the connecting portion 43. By having the recess 44, the printed circuit board 31 gets stuck into the recess 44, and it becomes easier for the substrate pressing portion 41 to contact the upper surface 31b of the printed circuit board 31. That is, it becomes easier for the substrate pressing portion 41 to press the printed circuit board 31.

[0058] In this embodiment, the elastic member 40 has two columnar portions 45, 46. By adopting such a divided structure, the substrate pressing portion 41 and the connecting portion 43 are more likely to elastically deform. For example, it becomes easier to insert through the through hole 311. Note that the number of columnar portions is not limited to two. Three or more columnar portions may be adopted.

[0059] <Modification Example> The electronic component 32 is preferably arranged at least on the lower surface 31a of the printed circuit board 31. The electronic component 32 may be arranged only on the lower surface 31a. In this case, it is possible to effectively suppress the occurrence of problems due to substrate chips.

[0060] If the substrate pressing portion 41 is widened by the insertion of the upper protrusion 222 and comes into contact with the upper surface 31b, the elastic member 40 may be configured not to have the recess 44.

[0061] The upper case 22 may be configured not to have the upper protrusion 222, and the substrate pressing portion 41 may be configured not to have the upper case fixing portion 411 for accommodating the upper protrusion 222. The substrate pressing portion 41 may be compressed, for example, between the inner surface of the bottom wall 221 and the upper surface 31b of the printed circuit board 31.

[0062] (Second Embodiment) This embodiment is a modification based on the preceding embodiment, and the description of the preceding embodiment can be incorporated. In the preceding embodiment, the substrate pressing portion 41 and the connecting portion 43 are constituted by a plurality of columnar portions 45, 46. Instead of this, the substrate pressing portion 41 and the connecting portion 43 may be constituted by a cylindrical portion.

[0063] FIG. 13 is a view showing the elastic member 40 in the electronic device 10 according to this embodiment. FIG. 13(a) is a plan view seen from the Z direction, and FIG. 13(b) is a side view seen from the B13 direction of FIG. 13(a). FIG. 13(a) corresponds to FIG. 7(a), and FIG. 13(b) corresponds to FIG. 7(b). FIG. 14 is a cross-sectional view showing the support structure of the printed circuit board 31 by the elastic member 40. FIG. 14 corresponds to FIG. 9.

[0064] As shown in FIG. 13, the elastic member 40 has a cylindrical portion 47 that is continuous with the inner peripheral end of the holding portion 42 having an umbrella shape and extends in the Z direction from the inner peripheral end. The cylindrical portion 47 has a substantially cylindrical shape. The hollow of the cylindrical portion 47 communicates with the accommodation space of the lower case fixing portion 421. The cylindrical portion 47 constitutes the substrate pressing portion 41 and the connecting portion 43. The portion of the cylindrical portion 47 on the holding portion 42 side constitutes the connecting portion 43, and the portion above the connecting portion 43 constitutes the substrate pressing portion 41.

[0065] As shown in FIG. 14, the cylindrical portion 47 also has a recess 44. The recess 44 is provided from the substrate pressing portion 41 to the connecting portion 43 so that the substrate pressing portion 41 contacts the upper surface 31b of the printed circuit board 31. The recess 44 is provided over the entire circumference along the outer peripheral surface of the cylindrical portion 47. Other configurations are the same as those shown in the previous embodiment. The cross-sectional structure in the ZX plane is the same as that in FIG. 8.

[0066] The substrate pressing portion 41 has a cylindrical shape. The substrate pressing portion 41 is in close contact with the entire circumference of the opening peripheral portion of the through hole 311 on the upper surface 31b. The substrate pressing portion 41 is in close contact with the entire circumference of the side surface of the upper protrusion 222. The connecting portion 43 also has a cylindrical shape. The connecting portion 43 is in close contact with the entire circumference near the lower end of the wall surface of the through hole 311.

[0067] <Summary of the Second Embodiment> According to the present embodiment, the same effects as those of the configuration described in the first embodiment can be achieved. Further, a cylindrical portion 47 is employed instead of the columnar portions 45 and 46. The cylindrical portion 47 is in close contact with the printed circuit board 31 so as to continuously surround the through hole 311. Thereby, it is possible to suppress the scattering of the substrate chips through the through hole 311 to the region on the upper surface 31b side of the accommodation space 20S.

[0068] To suppress the scattering to the region on the upper surface 31b side, only the substrate pressing portion 41 may be in close contact with the printed circuit board 31 so as to continuously surround the through hole 311, or only the connecting portion 43 may be in close contact with the printed circuit board 31 so as to continuously surround the through hole 311. In the present embodiment, the substrate pressing portion 41 is in close contact with the entire circumference of the opening peripheral portion of the through hole 311 on the upper surface 31b. Further, the connecting portion 43 is in close contact with the entire circumference near the lower end of the wall surface of the through hole 311. Since such a double close contact structure is adopted, it is possible to effectively suppress the scattering of the substrate chips to the region on the upper surface 31b side.

[0069] In this embodiment, the substrate pressing portion 41 is in close contact with the side surface of the upper protrusion 222 over the entire circumference. Thereby, it is possible to suppress the scattering of substrate chips into the region on the upper surface 31b side through the hollow of the cylindrical portion 47. In combination with the close contact structure with the printed circuit board 31, it is possible to effectively suppress the scattering of substrate chips into the region on the upper surface 31b side.

[0070] Although an example in which the elastic member 40 has the concave portion 44 has been shown, the present invention is not limited thereto. A configuration without the concave portion 44 may be adopted. In a configuration without the concave portion 44, the connecting portion 43 may be in close contact with substantially the entire wall surface of the through hole 311.

[0071] (Third Embodiment) This embodiment is a modified example based on the preceding embodiment, and the description of the preceding embodiment can be incorporated by reference. In the preceding embodiment, the holding portion 42 had an umbrella shape (suction cup shape). Instead, a shape different from the umbrella shape may be adopted.

[0072] FIG. 15 is a view showing the holding portion 42 of the elastic member 40 in the electronic device 10 according to this embodiment. The holding portion 42 shown in FIG. 15(a) has a tapered portion 423 on the surface facing the lower case 21. Thereby, the thickness gradually decreases from the inner peripheral end to the outer peripheral end within a predetermined range in the radial direction. Further, a concave portion 424 is provided on the surface facing the printed circuit board 31. At least a part of the concave portion 424 overlaps the tapered portion 423 in plan view. The tapered portion 423 and the concave portion 424 are provided in an annular shape along the circumferential direction so as to surround the inner peripheral end. In the case of this structure, the portion on the outer peripheral end side of the concave portion 424 is in close contact with the lower surface 31a of the printed circuit board 31.

[0073] The holding part 42 shown in Fig. 15(b) has convex parts 425 provided in multiple stages with respect to the configuration shown in Fig. 15(a). The convex parts 425 are provided in multiple stages in the radial direction at a portion on the outer peripheral end side rather than the concave part 424. Each of the convex parts 425 is provided annularly along the circumferential direction so as to surround the inner peripheral end. According to this, any one of the convex parts 425 provided in multiple stages adheres to the lower surface 31a over the entire circumference. That is, it becomes easier to adhere to the lower surface 31a over the entire circumference.

[0074] In addition, in the configuration shown in Fig. 15(b), the tapered part 423 may be excluded. Also, the number of stages of the convex parts 425 is not limited. They may be provided in even more stages.

[0075] (Other Embodiments) The disclosure in this specification, drawings, etc. is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and modifications by those skilled in the art based on them. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented by various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes those in which parts and / or elements of the embodiments are omitted. The disclosure includes the replacement or combination of parts and / or elements between one embodiment and another. The disclosed technical scope is not limited to the description of the embodiments. Some of the disclosed technical scopes should be understood to be indicated by the description of the claims and to include all changes within the meaning and scope equivalent to the description of the claims.

[0076] The disclosure in the specification, drawings, etc. is not limited by the description of the claims. The disclosure in the specification, drawings, etc. includes the technical idea described in the claims and extends to more diverse and extensive technical ideas than the technical idea described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being restricted by the description of the claims.

[0077] The spatially relative terms "lower" and "upper" are used herein to facilitate descriptions of the relationship of one element or feature to another element or feature as illustrated. The spatially relative terms are intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the drawings. For example, if the device in the figures is turned over, an element described as "lower" than another element or feature will be oriented "upper" relative to the other element or feature. Thus, the term "lower" can encompass both upward and downward orientations. The device may be oriented in other directions (rotated 90 degrees or otherwise), and the spatially relative descriptors used in this specification will be interpreted accordingly.

[0078] Although an example in which the connecting portion 43 has a hollow is shown, the present invention is not limited to this. A configuration without a hollow may be adopted. In a configuration where the upper projection 222 is not inserted, the substrate pressing portion 41 may have a configuration without a hollow. For example, instead of the cylindrical portion 47, a columnar portion without a hollow may be employed.

[0079] The shape of the lower projection 213 and the number of the contacts 213a are not limited to the above-described examples. The lower projection 213 may be provided so as to have only a portion overlapping with the conductor pattern 312, that is, only the contacts 213a. Considering the support structure of the printed circuit board 31, it is preferable to provide the lower projection 213 with a plurality of contacts 213a. For example, the lower projection 213 may have a planar cross shape and have a configuration with four contacts 213a.

Description of Reference Numerals

[0080] 10... Electronic device, 20... Housing, 20S... Accommodation space, 201... Opening, 21... Lower case, 211... Bottom wall, 212... Pedestal, 213... Lower protrusion, 213a... Contact, 22... Upper case, 221... Bottom wall, 222... Upper protrusion, 23... Screw, 30... Circuit board, 31... Printed circuit board, 31a... Lower surface, 31b... Upper surface, 311... Through hole, 312... Conductor pattern, 32... Electronic component, 33... Connector, 40... Elastic member, 41... Board pressing part, 411... Upper case fixing part, 42... Holding part, 421... Lower case fixing part, 422... Contact part, 423... Taper part, 424... Recess, 425... Protrusion, 43... Connecting part, 44... Recess, 45, 46... Columnar part, 47... Cylindrical part

Claims

1. A printed circuit board (31) having a through-hole (311) opening to a lower surface (31a) and an upper surface (31b), and a conductor pattern (312) provided around the opening of the through-hole on the lower surface; A conductive lower case (21) having a pedestal (212) on which the printed circuit board is mounted and a lower protrusion (213) protruding from the front end surface of the pedestal, and being disposed on the lower surface side of the printed circuit board; An upper case (22) disposed on the upper surface side of the printed circuit board and providing an accommodation space for the printed circuit board together with the lower case; A substrate pressing portion (41) that is compressed between the upper case and the printed circuit board and presses the printed circuit board against the pedestal from the upper surface side by the reaction force of elastic deformation, thereby supporting the printed circuit board and bringing the conductor pattern into contact with the lower protrusion to electrically connect to the lower case; a holding portion (42) having an annular shape surrounding the lower protrusion, an inner peripheral end of which is in close contact with the entire circumference of the side surface of the lower protrusion and is in close contact with the lower surface of the printed circuit board so as to continuously surround the pedestal, the lower protrusion, and the conductor pattern; and a connecting portion (43) connecting the substrate pressing portion and the holding portion, at least a part of which is disposed in the through-hole. An elastic member (40) having the above; An electronic device comprising the above.

2. Comprising an electronic component (32) mounted on the printed circuit board, The electronic component is disposed at least on the lower surface. The electronic device according to claim 1.

3. The holding portion has an umbrella shape, An outer peripheral end of the holding portion is in close contact with the lower surface of the printed circuit board over the entire circumference. The electronic device according to claim 1 or claim 2.

4. The upper case has an upper protrusion (222), The substrate pressing portion has an upper case fixing portion (411) that provides an accommodation space for the upper protrusion, and the upper protrusion is inserted into the accommodation space and is pushed by the upper protrusion to expand. The electronic device according to any one of claims 1 to 3.

5. The elastic member has a recess (44) provided on an outer surface extending from the substrate pressing portion to the connecting portion. The electronic device according to any one of claims 1 to 4.

6. The elastic member has a cylindrical portion (47) extending from an inner peripheral end of the holding portion and constituting the substrate pressing portion and the connecting portion, The cylindrical portion is in close contact with the printed circuit board so as to continuously surround the through-hole. The electronic device according to any one of claims 1 to 5.

7. The electronic device according to any one of claims 1 to 5, wherein the elastic member extends from an inner peripheral end of the holding portion and has a plurality of columnar portions (45, 46) constituting the substrate pressing portion and the connecting portion.

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