Electronic device and electronic timepiece

Abstract

To ensure a conduction path to GND collectively even in a case of including a plurality of conductive members.SOLUTION: A timepiece 100, which is an electronic device, includes: a first metal component and a second metal component that are externally mounted to a case 1; an external terminal plate 8 which is a first terminal plate and is electrically connected to the first metal component and the second metal component on an outside of the case 1; and a diaphragm 42 of a piezoelectric sound-generating unit 4 as a GND functional section which is provided inside the case 1 and functions as GND. The external terminal plate 8, which is the first terminal plate, is electrically connected to the diaphragm 42 as the GND functional section.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an electronic device and an electronic clock.

Background Art

[0002] Conventionally, various members made of a conductive material such as metal have been provided in electronic devices such as clocks. For example, Patent Document 1 describes a switch structure in which a conductive path is formed between a button made of a conductive material and a wiring pattern formed on a circuit board via a zebra type connector, and the wiring pattern formed on the circuit board and the button are electrically connected through the conductive rubber portion of the zebra type connector by pushing the button.

[0003] Recently, there are also many electronic devices provided with an antenna or the like capable of receiving a GPS signal for time correction or the like.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When a conductive member such as metal is mounted outside an electronic device, there is a problem that it affects the antenna sensitivity inside the electronic device. In order to eliminate the influence on the antenna sensitivity, it is required to electrically connect a conductive member such as metal to GND to make the potential difference zero. However, individually providing a conductive path for electrically connecting each member to GND complicates the configuration of the electronic device and also increases the restrictions on the arrangement of the members. Patent Document 1 does not mention anything about a configuration for electrically connecting a plurality of conductive members to GND at all.

[0006] The present invention is for solving such problems, and an object thereof is to provide an electronic device and an electronic clock capable of collectively securing a conduction path to GND even when a plurality of conductive members are provided.

Means for Solving the Problems

[0007] In order to solve the above problems, an electronic device according to the present invention includes: a first metal part and a second metal part that are externally mounted on a case; a first terminal board that is electrically connected to the first metal part and the second metal part outside the case; a GND functional part that is provided inside the case and is electrically connected to the first terminal board; and is characterized by including the above.

Effects of the Invention

[0008] According to the present invention, even when a plurality of conductive members are provided, a conduction path to GND can be collectively secured.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 8

Figure 9

Figure 10

Figure 11

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Figure 14

Figure 15

Figure 16

Figure 17

Embodiments for Carrying Out the Invention

[0010] With reference to the drawings, an embodiment of an electronic device (electronic clock) according to the present invention will be described. In this embodiment, a case where the electronic device (electronic clock) is a wristwatch (hereinafter simply referred to as "watch 100") used by being worn on the user's wrist will be exemplified and described. Note that various technically preferable limitations are imposed on the embodiments described below for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

[0011] [Configuration] FIG. 1 is a perspective view of the main part of a clock, which is an electronic device (electronic clock) in the present embodiment, FIG. 2 is a front view of the main part of the clock shown in FIG. 1. Further, FIG. 3 is a cross-sectional view of the main part along line III-III of the clock in FIG. 2, and FIG. 4 is a cross-sectional view of the main part along line IV-IV of the clock in FIG. 2. In addition, FIG. 5 is a side view of the 9 o'clock side of the clock as viewed from the direction of arrow V in FIG. 2, and FIG. 6 is a side view of the 3 o'clock side of the clock as viewed from the direction of arrow VI in FIG. 2.

[0012] As shown in FIG. 1, the clock 100, which is an electronic device (electronic clock) in the present embodiment, has a case 1. The case 1 of the present embodiment is formed in a hollow short column shape with openings at the top and bottom, and the internal hollow portion constitutes a storage space for storing various components. The case 1 is formed of a relatively hard synthetic resin such as engineering plastic or super engineering plastic. Note that the material forming the case 1 is not limited to those exemplified here.

[0013] On the outer surface of the case 1, a pair of band attachment portions 11 to which bands (not shown) are attached are provided at the 12 o'clock position and the 6 o'clock position in an analog clock. In addition, as will be described later, the clock 100 of the present embodiment is provided with metal buttons 7 at the 2 o'clock position, 4 o'clock position, 8 o'clock position, 9 o'clock position, and 10 o'clock position in an analog clock. Through holes 17 for inserting the shaft portions 72 of the metal buttons 7, which will be described later, are formed at positions on the outer surface of the case 1 corresponding to the metal buttons 7.

[0014] As shown in FIGS. 3 and 4, the opening portion on the front surface side (the visible side in the watch, the upper side in FIGS. 3 and 4) of the case 1 is closed by the windshield member 14. The windshield member 14 is a transparent member (cover member) formed of, for example, a glass material, a transparent resin material, or the like, and is fixed to the case 1 by, for example, adhesion. A transparent or translucent solar panel 15 is superimposed on the windshield member 14 and is provided integrally with the windshield member 14 by, for example, adhesive fixation (see FIGS. 3 and 4). Note that the shape and the position where the solar panel 15 is arranged are not limited to the illustrated examples.

[0015] The opening portion on the back surface side (the non-visible side in the watch, the lower side in FIGS. 3 and 4) of the case 1 is closed by the back cover member 3. Note that the back cover member 3 may be integrally formed with the case 1. The back cover member 3 is formed of, for example, a hard resin such as carbon or a metal resin. Thereby, the back cover member 3 can be configured to have high strength and be hardly affected even when receiving an impact. In the present embodiment, there is a recess 16 (see FIG. 9) for arranging a waterproof member such as a waterproof ring (not shown) on the end surface on the back surface side of the case 1, and the back cover member 3 is attached to the case 1 by a screw (not shown) via the waterproof member. By attaching the back cover member 3 via the waterproof member, the opening portion on the back surface side (the non-visible side in the watch) of the case 1 can be closed while ensuring the waterproof property (airtightness) inside the case 1.

[0016] In this embodiment, a piezoelectric sound - generating unit 4 is disposed inside the back - cover member 3 (see FIGS. 11 and 12). The piezoelectric sound - generating unit 4 generates a beep sound (rings a buzzer) to give various notifications to the user or the like, and is a unimorph structure in which a piezoelectric body 41 is adhered to a diaphragm 42. The diaphragm 42 is a metal plate member (sheet metal) such as stainless steel (SUS), and as will be described later, it is a metal plate that functions as GND (this is also referred to as a "GND functional part"). The piezoelectric sound - generating unit 4 is adhered to the inner surface of the back - cover member 3 by, for example, a double - sided tape 45 (see FIG. 12) and is connected to a circuit board (not shown). Note that the diaphragm 42 is not limited to stainless steel (SUS) and may be brass, nickel, or the like.

[0017] Although detailed illustration and description are omitted, inside the case 1 (the above - mentioned storage space), a control unit, an operation unit, a battery, and the like of the electronic device, the clock 100, are accommodated. The operation unit is a component for the clock 100 to perform various displays. For example, in FIG. 1 and the like, a case where the clock 100 has a digital display method including a display unit 12 including a liquid crystal (Liquid Crystal) display panel or the like as the operation unit is exemplified. Note that the operation unit is not limited to the display unit 12 including a liquid crystal display panel or the like. For example, when the clock 100 has an analog display method, as the operation unit, instead of the above - mentioned components, it has a pointer, a gear train (a wheel train mechanism) for rotating the pointer, a drive unit (a motor, etc.). Note that the clock 100 may be a hybrid type having both a digital method and an analog method. In this case, it has both sets of components as the operation unit. The control unit is mounted on a circuit board (not shown) or the like and controls the display operation and the like by the operation unit.

[0018] Also, an antenna 13 is disposed inside the case 1. In the example shown in FIG. 1, the antenna 13 is formed in a substantially annular shape and is disposed, for example, below the windshield member 14 (see FIGS. 3 and 4). Note that the shape of the antenna 13 and the position where the antenna 13 is provided are not limited to the illustrated examples. In the present embodiment, the antenna 13 is, for example, a GPS antenna capable of receiving GNSS (GPS / GLONASS / QZSS / SBAS) signals transmitted from satellites such as GPS (including multiple types such as GLONASS in addition to GPS, but simply referred to as "GPS" hereinafter). GPS satellites carry atomic clocks and transmit data including time information from these atomic clocks. By receiving GNSS (GPS) signals etc. transmitted from GPS satellites with the antenna 13, extremely high-precision time information can be obtained at any receiving point on the ground.

[0019] Also, as shown in FIGS. 1 to 6, a buffer bezel 5 is provided outside the case 1 of the present embodiment. The buffer bezel 5 is a buffer member that covers substantially the entire side surface of the case 1. Specifically, the buffer bezel 5 is provided so as to surround the opening portion on the surface side (the visible side of the watch) of the case 1 and covers substantially the entire side surface of the case 1. On the buffer bezel 5, a covering portion 51 is provided at a position corresponding to the band attachment portion 11 of the case 1 so as to cover the band attachment portion 11. Further, on the buffer bezel 5, an insertion hole 52 penetrating through the inside and outside is formed corresponding to the position where a metal button 7 described later is attached. The material forming the buffer bezel 5 is not particularly limited, but for example, it is formed of a resin such as urethane. Note that the buffer bezel 5 only needs to be formed of a material having a buffering effect and capable of restoring to its original shape even when pressed and deformed, and is not limited to the case of being formed of a resin such as urethane.

[0020] Also, a plurality of metal parts made of a metal material are externally mounted on the case 1. In the present embodiment, the metal parts include a metal bezel 6, a metal button 7, and a metal button pipe 75. Of the metal bezel 6, the metal button 7, and the metal button pipe 75 disposed on the 3 o'clock side shown in FIG. 1, any one is the first metal part, and any one of the other metal parts different from the first metal part is the second metal part. Further, the external terminal board 8 disposed on the 3 o'clock side shown in FIG. 1 and electrically connected to the first metal part and the second metal part is the first terminal board. Next, of the metal bezel 6, the metal button 7, and the metal button pipe 75 disposed on the 9 o'clock side shown in FIG. 1, any one is the third metal part, and any one of the other metal parts different from the third metal part is the fourth metal part. Further, the external terminal board 8 disposed on the 9 o'clock side shown in FIG. 1 and electrically connected to the third metal part and the fourth metal part is the second terminal board. As shown in FIGS. 2, 5 to 7(a), and 7(b), the metal bezel 6 is provided so as to cover from the outside of the buffer bezel 5 on the side portions of the case 1 on the 3 o'clock side and the 9 o'clock side in the analog type clock. By disposing the metal bezel 6 partially from the outside of the buffer bezel 5, the appearance design of the clock 100 can be improved and a high-class feeling can be produced. Note that the specific shape of the metal bezel 6, the position and range where the metal bezel 6 is disposed, etc. are not limited to the illustrated example, and the metal bezel 6 may be disposed over a wider range.

[0021] FIG. 8(a) is a perspective view showing the metal bezel. In FIG. 8(a), the metal bezel 6 disposed on the 3 o'clock side in the analog type clock is illustrated as an example. In the illustrated example, the metal bezel 6 is to be screwed at two locations, and screw holes 61 are formed at the locations to be screwed. As will be described later, the metal bezel 6 of the present embodiment is locked to the case 1 by a stepped screw 63 (see FIGS. 10(a) and 10(b)). As shown in FIG. 8(a), a butting surface 62 against which the first stepped portion 632 of the stepped screw 63 abuts is provided in the screw hole 61 formed in the metal bezel 6.

[0022] In addition, in the clock 100 of the present embodiment, metal buttons 7 are provided at the 2 o'clock position, 4 o'clock position, 8 o'clock position, 9 o'clock position, and 10 o'clock position of the analog clock. A metal button pipe 75, which is a metal part, is provided on the outer periphery of each metal button 7. FIG. 8(b) is an exploded perspective view of the metal button, and FIG. 8(c) is a perspective view of the metal button pipe. As shown in FIG. 8(b), the metal button 7 includes a button head 71 and a shaft portion 72. The button head 71 is exposed outside the clock 100 and is a part that receives the user's operation. One end side of the shaft portion 72 is connected to the button head 71, and the other end side is inserted into the insertion hole 77 (see FIG. 8(c)) of the metal button pipe 75 while being inserted through the coil spring member 73. Further, the other end side of the shaft portion 72 is inserted into the case 1 through the insertion hole 52 of the buffer bezel 5 and the through hole 17 of the case 1. In the present embodiment, in addition to the metal button pipe 75, the button head 71 and the shaft portion 72 are also metal parts formed of a metal material.

[0023] As shown in FIG. 8(c), the metal button pipe 75 is a bottomed substantially cylindrical member and has an insertion hole 77 in substantially the center of the bottom. A cylindrical portion 76, which is substantially concentric with the insertion hole 77 in plan view, stands upright from the bottom into the metal button pipe 75 around the insertion hole 77. When the shaft portion 72 of the metal button 7 is inserted into the insertion hole 77, one end side of the coil spring member 73 is disposed within the cylindrical portion 76. A recess 711 is formed around the shaft portion 72 on the back side of the button head 71 of the metal button 7 (see FIG. 9 etc.), and the other end side of the coil spring member 73 is disposed within the recess 711. Thereby, the button head 71 of the metal button 7 and the metal button pipe 75 are connected and electrically conducted via the coil spring member 73. Also, a screw hole 78 is formed near the insertion hole 77 at the bottom of the metal button pipe 75. As shown in FIG. 1, in the case 1, a positioning pin is formed on the back cover member 3 side rather than the through hole 17. Therefore, before the screw 74, which is a fastening member, is inserted into the screw hole 78, the positioning pin formed in the case 1 is inserted into one of the two screw holes 78 of the metal button pipe 75, and the metal button pipe 75 is fastened to the case 1 by inserting the screw 74, which is a fastening member, into the screw hole 78.

[0024] Furthermore, the timepiece 100 has a terminal board (hereinafter referred to as "external terminal board 8") that is connected to a plurality of metal parts outside the case 1, and the metal bezel 6 and the metal button pipe 75, which are a plurality of metal parts, are attached to the case 1 via the external terminal board 8. Specifically, the metal bezel 6 and the metal button pipe 75 are appropriately arranged from the outside of the buffer bezel 5 attached so as to cover the outside of the case 1 via the external terminal board 8, and are fastened to the case 1 by fastening members (the stepped screw 63, which is a fastening member for fastening the metal bezel 6, and the screw 74, which is a fastening member for fastening the metal button pipe 75).

[0025] The external terminal board 8 is formed of a metal material and has, as shown in FIG. 1, a component receiving portion 81, which is a planar portion for receiving the metal bezel 6 and the metal button pipe 75, and a connecting arm portion 82 that connects the component receiving portions 81. The component receiving portion 81 is provided with screw holes 83 for inserting the stepped screw 63 for fixing the metal bezel 6 and the screw 74 for fixing the metal button pipe 75.

[0026] The threaded section 63 and the screw 74 fix the metal bezel 6 and the metal button pipe 75 to the case 1 via the external terminal board 8. That is, both the metal bezel 6 and the metal button pipe 75 are clamped together with the external terminal board 8 to the case 1. By clamping together the metal bezel 6 and the metal button pipe 75, which are a plurality of metal parts, with the external terminal board 8, conduction is achieved between the members (i.e., the metal bezel 6 and the metal button pipe 75) fastened via the same external terminal board 8. Also, in the present embodiment, as described above, the button head 71 of the metal button 7 also contacts the metal button pipe 75 via the coil spring member 73. Therefore, when the button head 71 is also a metal part formed of a metal material, conduction is achieved between the button head 71 and other metal parts fastened via the same external terminal board 8. In this way, the metal button 7 is electrically connected to the external terminal board 8 via the coil spring member 73 and the metal button pipe 75.

[0027] In FIG. 3, which is a cross-sectional view taken along line III-III of FIG. 2, the metal buttons 7 at the 4 o'clock position and the 10 o'clock position are shown enclosed by a dashed line. In FIG. 4, which is a cross-sectional view taken along line IV-IV of FIG. 2, the metal buttons 7 at the 2 o'clock position and the 8 o'clock position are shown enclosed by a dashed line. In each figure, the metal button 7 enclosed by the dashed line and its surrounding configuration are substantially common. FIG. 9 is an enlarged cross-sectional view of the main part of the IX portion enclosed by the dashed line in FIG. 3.

[0028] The metal button 7 shown in FIG. 9 and the like is a push button that operates when the user presses the button head 71 and the shaft portion 72 is pushed in. The button head 71 is movable along the axis of the shaft portion 72 within the metal button pipe 75. Since the coil spring member 73 is arranged between the button head 71 and the metal button pipe 75 as described above, when the button head 71 is pressed, the coil spring member 73 is compressed. Then, when the pressing force is released, the button head 71 is pushed back by the restoring force of the coil spring member 73 and returns to its original position. As shown in FIG. 9, a groove portion 721 is formed in a portion of the shaft portion 72 that is inserted into the case 1, and a waterproof ring 722 is mounted in the groove portion 721. The number, shape, arrangement, etc. of the waterproof rings 722 are not limited to the illustrated example. The outer peripheral surfaces of the waterproof rings 722 are in pressure contact with the inner peripheral surface of the through hole 17 formed in the case 1, and slide within the through hole 17 in response to the operation of the metal button 7. Thereby, waterproofing between the shaft portion 72 and the through hole 17 is achieved.

[0029] Also, a groove portion 723 is formed around the axis in the vicinity of the tip of the shaft portion 72. When the shaft portion 72 is inserted through the through hole 17, at least the portion on the tip side of the groove portion 723 protrudes into the case 1. A retaining member 79 is attached to the groove portion 723. The shape, etc. of the retaining member 79 are not limited to the illustrated example, but for example, an E-ring or the like is applied as the retaining member 79 that is fitted into the groove portion 723. The retaining member 79 fitted into the groove portion 723 is configured to be able to contact and separate from the inner peripheral surface of the case 1. When the retaining member 79 contacts the inner peripheral surface of the case 1, the shaft portion 72 of the metal button 7 is configured such that the portion on the tip side of the groove portion 723 where the retaining member 79 is attached does not come out of the case 1.

[0030] As described above, the metal button pipe 75 is clamped together with the external terminal board 8 to the case 1 by a screw 74 with the external terminal board 8 sandwiched between the metal button pipe 75 and the outer peripheral surface of the case 1. Although only the component receiving portion 81 of the external terminal board 8 appears in the cross-section shown in FIG. 9, as described above, the external terminal board 8 is connected to a plurality of metal components by connecting a plurality of component receiving portions 81 by the connecting arm portion 82. On the portion of the shaft portion 72 of the metal button 7 on the tip side of the groove portion 723, one end side of the internal terminal plate 9 described later is in contact. As described above, a plurality of metal parts (the metal bezel 6, the metal button 7, and the metal button pipe 75 in FIG. 1) are connected to the external terminal plate 8. Any one of the plurality of metal parts (the metal bezel 6, the metal button 7, and the metal button pipe 75 in FIG. 1) is electrically connected to the internal terminal plate 9 (in direct or indirect contact). When the other end side of the internal terminal plate 9 comes into contact with the diaphragm 42 as the GND functional part, all of the plurality of metal parts (the metal bezel 6, the metal button 7, and the metal button pipe 75 in FIG. 1) connected to the external terminal plate 8 are electrically connected to GND, and the potential difference from GND becomes zero. The configuration in which the metal button 7 including the metal button pipe 75, which is a metal part, indirectly contacts the diaphragm 42 as the GND functional part will be described in detail later.

[0031] Also, in the timepiece 100 of the present embodiment, as shown in FIG. 2, the metal bezel 6 is provided on the outermost surface at the 3 o'clock side and the 9 o'clock side. For this reason, although it is excellent in appearance design, if a large impact is applied from the 3 o'clock side and the 9 o'clock side due to the dropping of the timepiece 100 or the like, the impact directly acts on the case 1 and various precision parts inside the case, which may have an adverse effect. Therefore, in the present embodiment, the following shock absorption structure is provided in the portion where the metal bezel 6 is provided. FIGS. 10(a) and 10(b) are enlarged cross-sectional views of the X portion surrounded by the dashed-dotted line in FIG. 7(a). Note that the shock absorption structure in the portion where the metal bezel 6 is provided is the same on the 3 o'clock side (that is, the side shown in FIG. 7(b)). Also, the configuration of the metal button 7 in the portion where the metal bezel 6 is provided is the same as that described with reference to FIG. 9, except that the shaft portion 72 is inserted into the case 1 through the insertion hole 67 of the metal bezel 6 instead of the insertion hole 77 of the metal button pipe 75. For this reason, the illustration is limited here and the description is omitted.

[0032] FIG. 10(a) shows a state where no load is applied to the metal bezel. As described above, the metal bezel 6 is fastened to the case 1 by the stepped screw 63. Specifically, a contact surface 62 against which the first stepped portion 632 of the stepped screw 63 abuts is provided in the screw hole 61 of the metal bezel 6. When the stepped screw 63 is fastened, the lower surface of the first stepped portion 632 (the right surface in FIG. 10(a)) abuts against the upper surface of the contact surface 62 (the left surface in FIG. 10(a)). As a result, the metal bezel 6 is electrically connected to the stepped screw 63.

[0033] Further, the second stepped portion 633 of the stepped screw 63 is in contact with the external terminal board 8 (the component receiving portion 81 of the external terminal board 8). The stepped screw 63 fastens the metal bezel 6 and the external terminal board 8 to the case 1 as a fastening member with the external terminal board 8 (the component receiving portion 81 of the external terminal board 8) sandwiched between the metal bezel 6 and the case 1. In the present embodiment, a buffer bezel 5 as a buffer member is disposed between the case 1 and the metal bezel 6. As shown in FIG. 10(a), the thickness of the buffer bezel 5 in a state where no load is applied to the metal bezel 6 is defined as "thickness t1". Also, at this time, a gap C is provided as a movable space capable of absorbing displacement of the metal bezel 6 between the metal bezel 6, which is an exterior member, and the case 1. The "thickness t1" of the buffer bezel 5 and the gap C as the movable space can be set as appropriate.

[0034] On the other hand, FIG. 10(b) shows a state where a load is applied to the metal bezel. When an impact is applied to the metal bezel 6, which is an exterior member, due to dropping of the timepiece 100 or the like, the metal bezel 6 is pushed toward the case 1 and displaced. At this time, the metal bezel 6 can move by the amount of the gap C, and the buffer bezel 5 is crushed by the amount the metal bezel 6 moves. Therefore, in a state where a load is applied to the metal bezel 6, the thickness of the buffer bezel 5 becomes "thickness t2", which is thinner than the "thickness t1" when no load was applied. Also, the gap C becomes smaller according to the amount of movement of the metal bezel 6. The illustrated example shows a state where the metal bezel 6 has moved to such an extent that the gap C has almost disappeared.

[0035] When the metal bezel 6 is displaced toward the case 1 side, the abutting surface 62 of the metal bezel 6 separates from the first step portion 632 of the stepped screw 63. Therefore, while they are separated, the metal bezel 6 is in a non-conductive state. However, when the state where a load is applied to the metal bezel 6 stops (that is, when the impact subsides), the buffer bezel 5 restores to its original shape. As a result, the metal bezel 6 is pushed up to its original position, the first step portion 632 of the stepped screw 63 abuts against the abutting surface 62 of the metal bezel 6 again, and the conductive state is restored.

[0036] Also, FIG. 11 is a plan view of the back cover member in the embodiment, and FIG. 12 is an exploded perspective view of the main part of the back cover member shown in FIG. 11. As described above, the piezoelectric sound emitting unit 4 is adhered to the inner surface of the back cover member 3 by a double-sided tape 45 or the like. FIG. 13 is an exploded perspective view of the main part of the piezoelectric sound emitting unit. In the present embodiment, the diaphragm 42 of the piezoelectric sound emitting unit 4 is a metal plate (GND functional part) that functions as GND. As shown in FIG. 13, the diaphragm 42 has a spring-shaped portion 43 at all or part of the position corresponding to the internal terminal plate 9.

[0037] The spring-shaped portion 43 is formed by bending a part of the diaphragm 42 substantially L-shaped toward the back surface to form a leaf spring shape. An elastic body 44 is disposed on the back surface side of the spring-shaped portion 43 (between the back cover member 3 and the spring-shaped portion 43). The elastic body 44 is an auxiliary member that generates a necessary load in the spring-shaped portion 43. That is, the spring-shaped portion 43 is provided to stably receive the end of the internal terminal plate 9 when the internal terminal plate 9 is disposed. The elastic body 44 secures a necessary contact pressure and stabilizes the contact resistance with the internal terminal plate 9.

[0038] The elastic body 44 is adhered to the back surface of the spring-shaped portion 43 with a double-sided tape or the like. As the elastic body 44, for example, a high-functional urethane foam such as a microcellular polymer sheet (e.g., "PORON" (registered trademark) manufactured by Rogers Inoaak Co., Ltd.) is preferably used. Note that the elastic body 44 only needs to be able to stabilize the load of the leaf spring-shaped portion 43, and its material is not particularly limited. For example, the elastic body 44 may be a coil spring or the like. FIG. 14 is a cross-sectional view of the main part along line XIV-XIV of the back cover in FIG. 11. As shown in FIG. 14 and the like, on the inner surface of the back cover member 3, at a position corresponding to the spring-shaped portion 43, a recess 31 for arranging the elastic body 44 provided on the back surface of the spring-shaped portion 43 is formed, and the elastic body 44 is stably arranged.

[0039] Note that the spring-shaped portions 43 are preferably provided corresponding to the positions of the respective metal buttons 7. Thereby, the internal terminal plate 9 that contacts the shaft portion 72 of each metal button 7 can be surely brought into contact with and electrically connected to the diaphragm 42 as the GND functional portion. However, although the internal terminal plate 9 is provided corresponding to the metal button 7, there may be a case where the spring-shaped portion 43 cannot be provided at the position corresponding to the internal terminal plate 9 due to the arrangement status of various components housed in the case 1 and the like.

[0040] In this regard, in the present embodiment, a plurality of metal components (metal bezel 6 and metal button pipe 75) are connected to one external terminal plate 8 and are in a state of being clamped together with the case 1. Therefore, for example, even if there is a location where the spring-shaped portion 43 cannot be arranged at the position corresponding to the internal terminal plate 9, if at least one of the internal terminal plates 9 corresponding to the other metal components connected to the same external terminal plate 8 is surely connected to the diaphragm 42, all the metal components connected to the external terminal plate 8 can be electrically connected to the diaphragm 42 as the GND functional portion, and a state of zero potential difference from GND can be achieved. The clock 100 of this embodiment is provided with five metal buttons 7, and corresponding internal terminal plates 9 are provided respectively. In FIGS. 12 and 13, a case where spring-shaped portions 43 are provided at four positions on the diaphragm 42 corresponding to four of these internal terminal plates 9 is illustrated.

[0041] FIG. 15 is a perspective view of the internal terminal plate in the embodiment. The internal terminal plate 9 is a metal plate that connects and conducts the metal bezel 6 and the metal button pipe 75, which are metal parts, to the diaphragm 42 that functions as GND. As shown in FIG. 15, the internal terminal plate 9 of this embodiment has a first portion 91 connected to a metal part and a second portion 92 bent in a first direction α (see FIG. 16) from the lower end side of the first portion 91, and is formed in a substantially L shape in side view. As shown in FIG. 16, in this embodiment, the first direction α is a direction from the inside to the outside of the case 1.

[0042] A curved portion 911 is formed at the upper end portion (free end portion) of the first portion 91 so as to receive and contact the tip of the shaft portion 72 of the metal button 7. Further, the second portion 92 is in surface contact with the diaphragm 42 which is a metal plate (specifically, the spring-shaped portion 43 formed integrally with the diaphragm 42). At this time, at the location where the spring-shaped portion 43 is provided, since the spring-shaped portion 43 is pushed up by the elastic body 44, it contacts so as to receive the second portion 92 from the diaphragm 42 side, and the internal terminal plate 9 and the diaphragm 42 can stably contact. Also, a double-sided tape 94 is disposed on the first portion 91 of the internal terminal plate 9, and the first portion 91 of the internal terminal plate 9 is attached to the case 1 via the double-sided tape 94.

[0043] In particular, the diaphragm 42 of the piezoelectric sound - emitting unit 4 has a relatively thin plate thickness for the purpose of vibrating the piezoelectric body 41. Just providing the spring - shaped portion 43 in the form of a leaf spring makes it difficult to generate a desired load. Further, when the piezoelectric sound - emitting unit 4 is provided on the back - cover member 3 as in the present embodiment, it is likely to cause poor contact due to repeated opening and closing operations. Also, even when contact is made and conduction is achieved, the contact resistance value is not stable (easily changed). In this regard, by providing an elastic body 44 on the back surface of the spring - shaped portion 43 and pushing it up by the elastic body 44, it is possible to ensure the necessary contact pressure with the internal terminal plate 9, and reliably conduct electricity between the internal terminal plate 9 and the diaphragm 42. Also, even when the opening and closing operations are repeated, the spring - shaped portion 43 is less likely to wear, and a long - term stable contact resistance can be maintained. Thereby, the resistance value of GND can be stabilized, and GND strengthening can be achieved.

[0044] Also, the internal terminal plate 9 in the embodiment has a bent portion 93 that projects in a substantially reverse L - shape in side view by bending the lower - end side of the first portion 91 in the second direction β (see FIG. 16) opposite to the first direction α, and the second portion 92 is formed by bending from the lower - end side of the bent portion 93 in the first direction α. By once bending the internal terminal plate 9 in the second direction β, bulging it in the inner direction of the case 1, and then bending it in the first direction α to form the second portion 92, the length of the second portion 92 in the first direction α can be increased. Therefore, even considering the bending R etc. when bending in the first direction α, the length of the second portion 92 can be sufficiently ensured, the contact area between the internal terminal plate 9 and the diaphragm 42 can be widened, and they can be made to contact more stably and conduct electricity.

[0045] Note that the configuration of the internal terminal plate 9 is not limited to what is exemplified here. For example, the internal terminal plate may not have the bent portion 93 bent in the second direction β, and as shown in FIG. 17, it may be an internal terminal plate 9a composed of a first portion 91a and a second portion 92a bent in the first direction α from the lower - end side of the first portion 91a, and formed in a substantially L - shape in side view. Also in this case, since the internal terminal plate 9a is bent in the first direction α on the lower end side of the first part 91a to form the second part 92a, an R shape (bending R) is formed at the bending angle between the first part 91a and the second part 92a by bending, which is a sheet metal process using the ductility of the metal. Therefore, the internal terminal plate 9a is separated from the case 1 by the amount of this bending R. However, by providing the double-sided tape 94 that attaches the first part 91a to the case 1 with thickness, adjustment is made to fill the gap generated between the first part 91a and the case 1 by the amount of the bending R.

[0046] FIG. 16 is an enlarged cross-sectional view of the XVI portion surrounded by the dashed-dotted line in FIG. 4. As shown in FIG. 16, the first part 91 of the internal terminal plate 9 is arranged at a position in contact with the tip side of the shaft portion 72 of the metal button 7. Also, the internal terminal plate 9 is bent in the first direction α after being once bent in the second direction β on the lower end side, and the second part 92 is formed. This second part 92 is in surface contact with the diaphragm 42 (the spring-shaped part 43 of the diaphragm 42). More specifically, the second part 92 is in surface contact with the spring-shaped part 43 integrally formed with the diaphragm 42. Thereby, the internal terminal plate 9 is stably electrically connected to the diaphragm 42 which is a metal plate.

[0047] The shaft portion 72 of the metal button 7 is in direct or indirect contact with the metal button pipe 75 which is a metal part. By bringing the internal terminal plate 9 in contact with the diaphragm 42 which functions as GND and is in contact with the shaft portion 72, a conduction path to GND is secured for the metal button pipe 75 and a plurality of metal parts connected to the same external terminal plate 8 as this metal button pipe 75, and they can be collectively conducted to GND. Thereby, the strengthening of GND can be achieved. Note that the case 1 has a recess 16 for arranging a waterproof member on the back-side end face. However, as shown in FIG. 16, both the internal terminal plate 9 and the diaphragm 42 which is a metal plate are arranged in a region that does not overlap with this recess 16 (a region inside the case 1 rather than the recess 16). Therefore, the waterproof property between the back cover member 3 and the case 1 is not impaired either.

[0048] [Operation] When assembling the clock 100 of this embodiment, the movement is housed in the case 1, and the opening portion on the visible side is closed by the windshield member 14. Further, the buffer bezel 5 is arranged so as to cover the outer portion of the case 1, and from the outside thereof, the metal bezel 6 which is a metal part and the metal button pipe 75 (the metal button 7 assembled to the metal button pipe 75) are attached via the external terminal board 8. At this time, the metal bezel 6 is attached to the case 1 by the stepped screw 63, and the metal button pipe 75 is attached to the case 1 by the screw 74. By screwing in the state where the external terminal board 8 is sandwiched between the plurality of metal parts and the case 1, the external terminal board 8 and the plurality of metal parts are clamped together with respect to the case 1.

[0049] The shaft portion 72 of the metal button 7 inserted through the insertion hole 77 of the metal button pipe 75 is inserted into the through hole 17 of the case 1, and the tip portion is disposed inside the case 1. A retaining member 79 is attached to the tip portion of the shaft portion 72 disposed inside the case 1 so that the shaft portion 72 does not come out of the case 1 and become detached. Further, the internal terminal board 9 is disposed so that the first portion 91 contacts the tip portion of the shaft portion 72.

[0050] When the parts of each part are mounted, the opening portion on the non-visible side is closed by the back cover member 3. At this time, a preventive member is disposed in the recess 16 of the case 1 to ensure waterproofing between the back cover member 3 and the case 1, and the back cover member 3 is screwed to the case 1. In the state where the back cover member 3 is attached, the spring-shaped portion 43 of the diaphragm 42 is disposed under the second portion 92 of the internal terminal board 9, and the second portion 92 of the internal terminal board 9 is pushed up by the elastic body 44 and the spring-shaped portion 43 is in surface-to-surface contact and conduction is ensured. By making contact in this way, stable contact and conduction are possible without being affected by displacement or the like. Note that at locations where the spring-shaped portion 43 is not provided, the load may not be stable and it may be difficult to reliably conduct to the GND. However, the plurality of metal parts are clamped together with the external terminal board 8 outside the case 1 and are electrically connected to each other. Therefore, if even one of the plurality of metal parts in contact with one external terminal board 8 comes into contact with the spring-shaped portion 43, all the metal parts in contact with the external terminal board 8 can be collectively conducted to the GND, and the GND can be strengthened.

[0051] As a result, a conduction path from the plurality of externally mounted metal parts (such as the metal bezel 6, the metal button 7, and the metal button pipe 75) to the GND (the diaphragm 42 that functions as the GND) inside the case 1 is ensured, and the plurality of metal parts can be reliably dropped to the GND. By electrically connecting the metal parts to the GND, it is possible to prevent the sensitivity (performance) of the antenna 13 provided inside the clock 100 from being affected by the metal parts, and a highly reliable clock 100 for time correction and the like using the antenna 13 can be realized.

[0052] Also, the metal bezel 6 as an exterior member is attached to the case 1 using a stepped screw 63, and a gap C as a movable space that allows the movement of the metal bezel 6 is provided between the metal bezel 6 and the case 1. Even when the metal bezel 6 is pushed in by an impact such as a drop, the displacement can be absorbed in the gap C. Furthermore, by disposing a buffer bezel 5 as a buffer member between the metal bezel 6 and the case 1, the impact can be absorbed and alleviated. For this reason, it is not necessary to add various additives to the case 1 itself for strengthening, and there is no influence on the antenna performance due to the additives.

[0053] [Effect] As described above, the clock 100, which is an electronic device in this embodiment, includes a plurality of metal parts, i.e., a first metal part and a second metal part, that are externally mounted on the case 1, and an external terminal board 8, which is a first terminal board that is electrically connected to the first metal part and the second metal part on the outside of the case 1, and a diaphragm 42, which is provided inside the case 1 and functions as a GND part that is electrically connected to the external terminal board 8. Thereby, even when a plurality of metal parts, which are conductive members, are externally mounted on the case 1, it is possible to secure a conduction path from all the metal parts to the diaphragm 42 that serves as GND, and the metal parts can be made to be in a state without a potential difference from GND. For this reason, with a relatively simple configuration, it is possible to suppress the influence on precision devices inside the electronic device such as the clock 100. Particularly when the clock 100 has such a configuration as in this embodiment, it is possible to realize a high-class appearance design by externally mounting various metal parts. And while realizing a high-class feeling, it is possible to avoid the influence on the sensitivity (performance) of the internal antenna, and it is possible to realize high-precision radio wave reception, accurate time correction by the received radio wave, and the like.

[0054] Also, a third metal part and a fourth metal part different from the first metal part and the second metal part may be externally mounted on the case 1. In this case, a second terminal board (external terminal board 8) that is electrically connected to the third metal part and the fourth metal part is provided outside the case, and the GND functional part is also electrically connected to the second terminal board. For example, when the first metal part, the second metal part, and the first terminal board are arranged on the 3 o'clock side of the clock 100, and the third metal part, the fourth metal part, and the second terminal board are arranged on the 9 o'clock side of the clock 100, it is possible to secure a conduction path from each metal part to the diaphragm 42 that functions as GND, and all the externally mounted metal parts can be made to be in a state without a potential difference from GND. Thereby, it is possible to achieve both a high-class appearance design and avoidance of the influence on precision devices inside the device.

[0055] In this embodiment, the plurality of metal parts (the first metal part and the second metal part) include a metal bezel 6, a metal button 7, and a metal button pipe 75. Thereby, it is possible to realize a high-class appearance design in which metal parts such as the metal bezel 6, the metal button 7, and the metal button pipe 75 are arranged on the exterior. And while producing a high-class feeling, the metal parts can be collectively set in a state where there is no potential difference from the GND, and a state where the internal devices are not affected can be achieved.

[0056] In this embodiment, the metal bezel 6 and the metal button pipe 75 among the plurality of metal parts are attached to the case 1 by a screw 74 or a stepped screw 63 as a fastening member via an external terminal board 8. Thereby, for the metal parts connected to the same external terminal board 8, if even one of them can be stably connected to the GND, they can be collectively dropped to the GND, and a reduction in the number of parts and a simple configuration can be realized.

[0057] In this embodiment, the metal button 7 includes a button head 71 and a shaft portion 72 having one end connected to the button head 71 and the other end inserted through a coil spring member 73. The metal button 7 is electrically connected to an external terminal board 8 (the first terminal board, the second terminal board) via the coil spring member 73 and the metal button pipe 75. Thereby, without adding special parts, the electrical connection between the metal button 7 and the external terminal board 8 can be achieved by the parts normally provided on the metal button 7.

[0058] In this embodiment, an antenna 13 is provided in the case 1. When a conductive member such as metal is mounted outside an electronic device such as a clock 100, it affects the antenna sensitivity of the antenna 13 inside the electronic device. In order to eliminate the influence on the antenna sensitivity, it is necessary to conduct a conductive member such as metal to the GND and set the potential difference to a zero state. In this regard, in the present embodiment, by providing the external terminal board 8 connected to a plurality of metal parts, a plurality of metal parts can be collectively grounded without securing individual conduction paths for each part. Thereby, the influence on the antenna 13 can be suppressed with a relatively simple configuration, and highly accurate radio wave reception can be realized.

[0059] [Modification Example] Although the embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to such embodiments, and various modifications are possible without departing from the gist thereof.

[0060] For example, in the present embodiment, the external terminal board 8 is disposed at the 3 o'clock position and the 9 o'clock position in the analog clock, and is shown to be fastened together with at least one metal bezel 6 and the case 1 respectively. However, the position and range where the external terminal board 8 is provided, and the number and type of metal parts connected to one external terminal board 8 are not limited to those exemplified in the embodiment. Even more metal bezels 6 and metal button pipes 75 may be connected to one external terminal board 8. Also in this case, if any one of the metal parts connected by the external terminal board 8 is electrically connected to GND, all the metal parts connected to the external terminal board 8 can be electrically connected to GND. In the present embodiment, the metal parts include the metal bezel 6, the metal button 7, and the metal button pipe 75. However, the metal parts may include the metal bezel 6 and the metal button pipe 75, and instead of the metal button 7, an operation button formed of a material different from metal may be used.

[0061] Also in the present embodiment, the case where the buffer bezel 5 as a buffer member covers substantially the entire case 1 and the metal bezel 6 is disposed at the 3 o'clock position and the 9 o'clock position in the analog clock has been exemplified. However, the positions and ranges where the buffer bezel 5 and the metal bezel 6 are provided are not limited to those shown in the embodiment.

[0062] In addition, in this embodiment, the case where the diaphragm 42 of the piezoelectric sound - generating unit 4 functions as GND has been exemplified. However, the GND - functioning part may be a metal member provided inside the case 1 and indirectly connected to the external terminal board 8, and is not limited to the diaphragm 42.

[0063] Also, in this embodiment, the case where the electronic device is the wrist - watch - type clock 100 has been exemplified, but the electronic device is not limited to this. For example, it can be widely applied to various electronic devices such as smart watches and sports watches, and wearable devices that acquire biological information such as heart rate and blood flow information in addition to time.

[0064] Although some embodiments of the present invention have been described above, the scope of the present invention is not limited to the above - described embodiments, but includes the scope of the invention described in the claims and its equivalent scope.

Explanation of reference numerals

[0065] 1 Case 13 Antenna 14 Wind - proof member 17 Through - hole 3 Back - cover member 31 Recess 4 Piezoelectric sound - generating unit 42 Diaphragm (GND - functioning part, metal plate functioning as GND) 43 Spring - shaped part 44 Elastic body 5 Buffer bezel (buffer member) 6 Metal bezel (metal part) 62 Contact surface 63 Step - threaded screw (fastening member) 7 Metal button (metal part) 72 Shaft part 74 Screw (fastening member) 75 Metal - button pipe (metal part) 8 External terminal board (first terminal board, second terminal board) 81 Component receiving part 9 Internal terminal board 91 First part 92 First part 100 Watch (electronic device) C Gap (movable space)

Claims

1. A first metal part and a second metal part externally mounted on a case, a first terminal board electrically connected to the first metal part and the second metal part outside the case, a GND functional part provided inside the case and electrically connected to the first terminal board, comprising an electronic device characterized by this.

2. A third metal part and a fourth metal part externally mounted on the case, a second terminal board electrically connected to the third metal part and the fourth metal part outside the case, comprising the GND functional part is electrically connected to the second terminal board, the electronic device according to Claim 1, characterized by this.

3. Each of the first metal part, the second metal part, the third metal part, and the fourth metal part includes any one of a metal bezel, a metal button, and a metal button pipe, the electronic device according to Claim 2, characterized by this.

4. The metal button includes a button head and a shaft portion with one end connected to the button head and the other end inserted into a coil spring member, the metal button is electrically connected to the terminal board via the coil spring member and the metal button pipe, the electronic device according to Claim 3, characterized by this.

5. The first metal part and the second metal part are attached to the case by a fastening member via the first terminal board, the electronic device according to Claim 1, characterized by this.

6. The third metal part and the fourth metal part are attached to the case by a fastening member via the second terminal board, the electronic device according to Claim 2, characterized by this.

7. An antenna is provided inside the case, the electronic device according to Claim 1, characterized by this.

8. The GND functional part is a diaphragm made of a metal plate member, the electronic device according to Claim 1, characterized by this.

9. A first metal part and a second metal part externally mounted on a case, a first terminal board electrically connected to the first metal part and the second metal part outside the case, a GND functional part provided inside the case and electrically connected to the first terminal board, comprising an electronic clock characterized by this.

10. A third metal part and a fourth metal part externally mounted on the case, A second terminal board that is electrically connected to the third metal part and the fourth metal part on the outside of the case; comprising; the GND functional part is electrically connected to the second terminal board; The electronic timepiece according to claim 9, characterized by this.

11. The first metal part, the second metal part, and the first terminal board are arranged on the 3 o'clock side; The third metal part, the fourth metal part, and the second terminal board are arranged on the 9 o'clock side; The electronic timepiece according to claim 10, characterized by this.

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