Clock module and electronic clock

Abstract

To provide a clock module and an electronic clock capable of suppressing the reduction of reception sensitivity of an antenna even when a display screen and the antenna overlap.SOLUTION: A clock module includes a liquid crystal display screen (13), an antenna element (11) having an antenna pattern (112) relating to communication and an antenna component (111), and a metal component (12). The antenna pattern (112) has a curved shape in plan view and is positioned overlapping the liquid crystal display screen (13). The antenna element (11) is positioned so that either one side or the other side of a virtual line, which is the direction of extension of the antenna component (111) extending from the antenna pattern (112), does not overlap the metal component (12).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a time module and an electronic timepiece. [Background technology]

[0002] Some electronic watches, especially wristwatches worn on the wrist, are capable of performing many functions within the constraints of size and weight. Among these, electronic watches that can receive and communicate radio waves have an antenna used to transmit and receive the radio waves. If this antenna is subject to interference from other metal parts, it becomes difficult to transmit radio waves at an appropriate sensitivity. Therefore, the position of the antenna relative to other metal parts is determined so that the transmission and reception sensitivity is not reduced as much as possible.

[0003] However, in electronic watches, it can be difficult to position the antenna in an ideal position in order to perform more functions while minimizing increases in size. Patent Document 1 discloses a technique for positioning the antenna so that, even if it overlaps with the liquid crystal display screen, it does not overlap with anything other than the display electrodes and some of the connecting wiring. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2017-83229 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, it may be difficult to adjust the positional relationship of the antenna to a display screen having a large number of display pixels.

[0006] An object of the present invention is to provide a timepiece module and an electronic timepiece that can prevent a decrease in antenna reception sensitivity even when the display screen and antenna overlap. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention provides A digital display screen, an antenna element having an antenna pattern related to communication and an antenna part connected to the antenna pattern and extending from the antenna pattern; Metal parts, Equipped with the antenna pattern has a curved shape in a plan view and is positioned so as to overlap the digital display screen; The antenna element is positioned so that the outer periphery of the watch module, which is located on one side of an imaginary line that is the extension direction of the antenna part extending from the antenna pattern, does not overlap with the metal part. And, The antenna component is rectangular in plan view, The extension direction of the antenna part is the longitudinal direction of the antenna part. R Clock module. Effect of the Invention

[0008] According to the present invention, even if the display screen and the antenna overlap, it is possible to suppress a decrease in the reception sensitivity of the antenna. [Brief description of the drawings]

[0009] [Figure 1] 13 is a bottom view illustrating the positional relationship of the antenna elements in the watch module. FIG. [Diagram 2] FIG. 2 is a cross-sectional view of a watch module. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a bottom view illustrating the positional relationship of the antenna element 11 in the watch module 100 of this embodiment. Fig. 2 is a cross-sectional view of the watch module 100 taken along the cross-sectional line AA.

[0011] In Fig. 1, the positional relationship of the antenna element 11 and the liquid crystal display screen 13 (digital display screen) with respect to the metal part 12 is indicated by dashed lines. An electronic watch using the watch module 100 uses, for example, both a pointer display and a liquid crystal display. For this reason, the liquid crystal display screen 13 is on one side of a center position O that is the axis of rotation of the pointer (not shown), here on the lower left side in Fig. 1. Since Fig. 1 is a bottom view of the watch (a view seen from the back side), the liquid crystal display screen 13 occupies a main position between the 3 o'clock direction and the 6 o'clock direction. As shown in Fig. 2, the liquid crystal display screen 13 is fixed by a resin part 16. The liquid crystal display screen 13 displays digital data, for example, by a dot matrix.

[0012] The antenna element 11 has an antenna part 111 and an antenna pattern 112. As shown in FIG. 1, the antenna part 111 is connected to the antenna pattern 112 related to communication and extends from the antenna pattern 112. The antenna pattern 112 (antenna element) is a monopole antenna (including an inverted L shape, etc.) having a gentle arc shape (curved shape) with a large radius of curvature compared to its length in a plan view (a see-through shape when it is hidden by other parts, etc. and part or all of it is not visible) seen from above the liquid crystal display screen 13 (the +z side in FIG. 2). As a result, the actual length of the antenna pattern 112 is slightly (several percent to several tens of percent) longer than the length (for example, 1 / 8 of the wavelength, etc.) corresponding to the wavelength of the frequency (used frequency) related to transmission and reception (either one may be used). This increase in length increases the transmission and reception area of ​​radio waves while preventing a large difference in the transmission and reception frequencies of radio waves, thereby improving sensitivity. Here, the antenna element 11 is used for short-distance wireless communication, particularly for communication in the 2.4 GHz band by Bluetooth (registered trademark).

[0013] The antenna element 11 can be trimmed to adjust the reception frequency, including the increased length of the antenna pattern 112, by adjusting the capacitance of a capacitor (not shown) located within the watch module 100.

[0014] The antenna component 111 is not particularly limited, but for example, has a rectangular shape in a plan view seen from above the liquid crystal display screen 13, and is positioned near an end of the antenna pattern 112 so as to protrude from a surface including the antenna pattern 112. The antenna component 111 is positioned such that its longitudinal direction is oriented along a direction perpendicular to the contact surface with the antenna pattern 112. In addition, as shown in FIG. 2, the antenna component 111 is connected and fixed to the substrate 15, and transmission and reception data are input and output between the antenna component 111 and a signal line of the substrate 15.

[0015] 1, antenna element 11 is positioned so as to overlap liquid crystal display screen 13 in a plan view. Even in this case, it is best to position antenna element 11 as close to the outer edge of watch module 100 as possible. As a result, antenna element 11 is positioned slightly inside the outer edge of watch module 100. Meanwhile, a distance (clearance) is maintained between the periphery of antenna element 11 and metal part 12 to reduce interference with the transmission and reception of radio waves.

[0016] The metal part 12 includes a pressing member 121 that fixes the entire watch module 100 inside the case of the watch, and a member 122 for fixing the battery in an appropriate position. Objects that are fixed by the pressing member 121 include the board 15 and the housing.

[0017] The housing includes a resin part 16. The housing contains components related to digital display, including the above-mentioned liquid crystal display screen 13, and components related to pointer display, such as the hands, gear train (wheel train mechanism), and stepping motor. The metal part 12 also has a leaf spring that generates elastic stress for the push button switch located on the side of the watch. The metal part 12 also functions as a grounding surface for the case, and may be electrically connected to the grounding surface on the board 15. The metal part 12 may also include screws, springs, the battery itself, and the like (not shown). The battery is a button battery, or it may be a secondary battery.

[0018] The cross-sectional line AA in the cross-sectional view shown in Fig. 2 extends perpendicular to the direction of the antenna component 111. On this cross-sectional line AA, the watch module 100 is stacked in the following order from the bottom in Fig. 2, i.e., from the top side (+z direction): the liquid crystal display screen 13, the resin component 16, the antenna element 11, the substrate 15, the insulating sheet 14, and the metal component 12. Pressing member 121 of metal part 12 in Fig. 2 is a portion located to the left of antenna pattern 112 in Fig. 1, and member 122 of metal part 12 in Fig. 2 is a portion located to the upper right of antenna pattern 112 in Fig. 1. Note that hatched areas in Fig. 2 indicate cross sections of the corresponding members, and the areas of insulating sheet 14, pressing member 121, and member 122 on the left side of Fig. 2, which are members not hatched, are portions located behind the cross sections. Also, the convex portion located to the right of pressing member 121 in Fig. 2 is the leaf spring located at the upper left of the four leaf springs in Fig. 1.

[0019] The substrate 15 may be equipped with various electronic components for operating the electronic watch, such as IC chips, large-capacity capacitors, crystal oscillators, physical sensors, and communication control (which may include modulation and demodulation processing) circuits. The substrate 15 also has wiring and a ground surface that connects the electronic components. The substrate 15 is not particularly limited, and may be a laminated substrate having a substrate surface of multiple layers.

[0020] The insulating sheet 14 prevents other metal components 12 from coming into contact with the wiring or ground surface on the substrate 15 and causing a short circuit. The insulating sheet 14 includes an area that overlaps with the metal component 12 in a plan view, and is provided with an area slightly larger than the outer periphery of the metal component 12.

[0021] The direction along the orientation of the antenna component 111 indicated by the dashed line in FIG. 1 (the direction perpendicular to the plane of FIG. 2) represents the direction of radio wave emission from the antenna pattern 112 and / or the direction of radio wave incidence on the antenna pattern 112. In the watch module 100, the metal component 12 is not located in the extension direction of one outward side (the outer circumferential side of the watch module 100) of this antenna component 111. The metal components 12 are located on the left and right of the extension line of the outer circumferential side of the antenna component 111. Also, here, the direction perpendicular to each point on the side surface of the curved antenna pattern 112 (the outer surface side of the watch module 100, the side of the curvature center of the antenna pattern 112) is open in principle with no metal component 12 present. In other words, the antenna element 11 is located so that either one side or the other side of a virtual line (the dashed line in FIG. 1) which is the extension direction of the antenna component 111 extending from the antenna pattern 112 does not overlap the metal component 12. Of the two sides of the imaginary line, the one that does not overlap with the metal part 12 is the outer circumferential side.

[0022] The antenna pattern 112 and the pressing member 121 are positioned so that they are closest (shortest distance) at one end of the antenna pattern 112. The shortest distance at this time is determined to be equal to or greater than a reference value. Here, the reference value is 0.6 to 0.7 mm. By ensuring (separating) a certain distance (equal to or greater than the reference distance) between the end of the antenna pattern 112 and the pressing member 121, interference with radio wave transmission and reception by the metal part 12 can be suppressed.

[0023] In addition, wiring on the substrate 15, a ground plane, metal components of electronic components, and the like are not included in the metal component 12 of this embodiment. However, it is preferable to exclude these from the above range as much as possible. However, this does not apply to items that are difficult to exclude from the above range, including signal lines connecting to the antenna component 111, etc.

[0024] In this example, the insulating sheet 14 is open to match the open area of ​​the metal component 12, but since the insulating sheet 14 does not interfere with radio waves, there is no need to match it. The insulating sheet 14 may extend along the board 15 even in the open area.

[0025] In the electronic timepiece of this embodiment, the above-mentioned timepiece module 100 is housed in an exterior member (housing and bezel), and is sealed by covering the top with a crystal glass and the bottom with a back cover. Push button switches and the like protrude through the sides of these exterior members, and input operations from the outside move the leaf springs in the above-mentioned internal metal component 12. This allows the timepiece module 100 to detect the input operation and perform an operation in accordance with the input operation.

[0026] As described above, the timepiece module 100 of this embodiment includes the liquid crystal display screen 13, the antenna element 11 having the antenna pattern 112 and antenna part 111 related to communications, and the metal part 12. The antenna pattern 112 has a curved shape in a plan view, and is positioned so as to overlap the liquid crystal display screen 13. The antenna element 11 is positioned so that either one side or the other side of an imaginary line which is the extension direction of the antenna part 111 does not overlap the metal part 12. With this structure, even if antenna element 11 must be placed in a position that is covered from above by an LCD display screen or the like, it is possible to suppress interference between metal part 12 and antenna pattern 112 and prevent a decrease in reception sensitivity. This allows time module 100 to improve the freedom of placement, including antenna element 11. Therefore, time module 100 can be configured to provide multiple functions more efficiently.

[0027] Moreover, the antenna component 111 is rectangular in plan view, and its extension direction is the longitudinal direction of the antenna component 111. Of the two sides on the above-mentioned imaginary line, the one that does not overlap with the metal component 12 is the outer periphery side of the watch module 100. In other words, by avoiding overlap with the metal part 12 in the outer circumferential direction where radio waves are more likely to enter and exit, the timepiece module 100 can further improve its radio transmission and reception sensitivity.

[0028] Furthermore, the antenna pattern 112 may be longer than the length corresponding to the wavelength of the frequency used. By adopting a curved shape as described above, it is possible to make the antenna pattern 112 slightly longer even with the same width. By trimming this extended length with a capacitor, it is possible to maintain the tuning frequency at the desired frequency used. This allows the time module 100 to improve the reception sensitivity.

[0029] The frequency used may be a frequency related to short-range wireless communication, particularly Bluetooth. That is, the antenna element 11 may be one used for short-range wireless communication. The present invention is preferably applicable to cases where an antenna that is substantially linear in plan view can be arranged within the watch module 100, such as the 2.4 GHz band.

[0030] In addition, it is preferable that the metal part 12 is spaced apart from the antenna pattern 112 by a reference distance or more. By ensuring the overall distance between the antenna pattern 112 and the metal part 12, not just on the extension line of the antenna part 111, interference relating to radio wave transmission and reception can be effectively suppressed.

[0031] Furthermore, the curved shape of the antenna pattern 112 may be an arc shape. By not bending it too greatly or complicatedly, it is possible to increase the antenna length and improve the reception sensitivity while suppressing the decrease in reception efficiency.

[0032] The electronic timepiece of this embodiment also includes the above-mentioned timepiece module 100. This electronic timepiece can be efficiently equipped with a wider variety of configurations and can be used while suppressing increases in size and decreases in radio wave transmission and reception sensitivity.

[0033] The present invention is not limited to the above-described embodiment, but may be modified in various ways. For example, the short-range wireless communication may include WiFi in the same frequency band, or may comply with other communication standards.

[0034] Furthermore, the antenna pattern 112 does not have to be in the shape of a circular arc in a plan view, but may be in the shape of another curve, for example, a quadratic curve or a part of a hyperbola.

[0035] In the above embodiment, a liquid crystal display screen has been described as an example of a digital display screen, but this is not limiting. An organic EL (Electro-Luminescent) screen may also be used. Furthermore, the digital display screen is not limited to a dot matrix display.

[0036] Furthermore, the extent to which the open space of the metal component 12 is provided on the other side of the extension direction of the antenna component 111 (extension direction of the imaginary line), in other words, on the inside of the watch module 100, may be determined as appropriate.

[0037] In the above embodiment, one end of the antenna pattern 112 is located at the position with the shortest distance from the metal part 12, but this is not limited to this. The point with the shortest distance may be located above or below the antenna pattern 112.

[0038] Furthermore, the position where the antenna element 11 overlaps with the liquid crystal display screen 13 is not limited to the position shown in the above embodiment, but may be appropriately determined depending on the relationship with other electronic components, the metal component 12, and the like. In addition, the specific configurations, structures, positional relationships, etc. shown in the above embodiment can be modified as appropriate without departing from the spirit of the present invention. The scope of the present invention includes the scope of the invention described in the claims and its equivalents. [Explanation of symbols]

[0039] 11 Antenna elements 111 Antenna parts 112 Antenna Pattern 12 Metal parts 121 Holding member 122 Materials 13 LCD display screen 14 Insulation sheet 15 Substrate 16 Plastic parts 100 Clock Module

Claims

1. A digital display screen, an antenna element having an antenna pattern related to communication and an antenna part connected to the antenna pattern and extending from the antenna pattern; Metal parts, Equipped with the antenna pattern has a curved shape in a plan view and is positioned so as to overlap the digital display screen; the antenna element is positioned so that the outer periphery of the timepiece module, which is located on one side of an imaginary line that is an extension direction of the antenna part extending from the antenna pattern, does not overlap with the metal part, The antenna component is rectangular in plan view, The extension direction of the antenna part is the longitudinal direction of the antenna part. Clock module.

2. 2. The timepiece module according to claim 1, wherein the antenna element is used for short-range wireless communication.

3. 2. A timepiece module according to claim 1, wherein the antenna pattern is longer than a length corresponding to the wavelength of the frequency used.

4. 4. The timepiece module according to claim 3, wherein the frequency used is a frequency related to short-distance wireless communication.

5. 2. The timepiece module according to claim 1, wherein the metal part is spaced from the antenna pattern by a reference distance or more.

6. 2. The timepiece module according to claim 1, wherein the curved shape is a circular arc shape.

7. An electronic watch comprising the watch module according to any one of claims 1 to 6.

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