JP2020016563A - Electronic watch - Google Patents

Abstract

To reduce the thickness of an electronic watch comprising an antenna and a display wheel.SOLUTION: An electronic watch 1 comprises: an external case 5 having a back lid 4; a watch movement 10 comprising a day wheel 14 (display wheel); a circuit board 31 (a first board) on which a GND pattern 31b and a power feeding circuit 31c, which are arranged on a side of the back lid 4, of a watch module 12 forming the watch movement 10 are formed; an antenna board 32 (a second board) on which an antenna pattern 34 (antenna) which is arranged at a position at least partially overlapping the day wheel 14 in a thickness direction t of the watch is formed; and a conduction member 33 connecting the power feeding circuit 31c and the antenna pattern 34.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic timepiece.

  2. Description of the Related Art In recent years, electronic watches have various functions, and as their functions increase, electronic watches have increased in thickness. For example, in the case of an electronic timepiece having an antenna for receiving various electromagnetic waves, a circuit board having a receiving circuit is required in addition to the antenna.

  Then, from the viewpoint of improving the receiving sensitivity, it is desired that the antenna be arranged away from the conductor. For this reason, it is necessary to dispose the antenna away from the back cover of a metal watch case, a metal battery, and the like, and to arrange the antenna so that it cannot be seen from the outside. As an example, the antenna is arranged between the dial and the clock movement, and the circuit board is arranged on the side away from the antenna and near the back cover with the clock movement in between (for example, see Patent Document 1).

JP-A-2006-148611

  Here, in the case of a watch having a display car such as a date wheel or a day wheel that exhibits a calendar function or the like, a city display vehicle indicating a local zone of a displayed time, or a functional vehicle indicating an operation state, the display car is It is arranged between the antenna and the dial, and the thickness of the electronic timepiece is further increased. In other words, the display car displays a plurality of dates, days of the week, city names, function names, etc., arranged in the circumferential direction, and is disposed immediately below the dial (at a position close to the dial on the back side of the dial). Have been. Then, as the display car rotates, one date, day of the week, city name, or function name is superimposed on a window (opening) formed on the dial, and the date, day of the week, city name, or function name is visually recognized. It is configured as follows.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electronic timepiece having an antenna and a display wheel, which can reduce the thickness of the timepiece.

  The present invention provides an exterior case having a back cover, a watch movement having a display wheel, and a GND (ground) pattern and a power supply circuit which are arranged on the back cover side of a watch module constituting the watch movement. The first substrate, the second substrate on which the antenna is formed, at least a part of which is arranged at a position overlapping the display wheel in the thickness direction of the timepiece, and the power supply circuit and the antenna are connected. An electronic timepiece including a conduction member.

  ADVANTAGE OF THE INVENTION According to the electronic timepiece which concerns on this invention, even if it has an antenna and a display wheel, thickness can be made thin.

FIG. 1 is a cross-sectional view illustrating a cross section of a surface including a thickness direction t of an electronic timepiece that is a wristwatch as one embodiment of an electronic timepiece according to the present invention. FIG. 2 is a perspective view showing a timepiece movement in the electronic timepiece of FIG. 1. FIG. 3 is an exploded perspective view showing a state where a date wheel holder (display wheel holder) and an antenna substrate (second substrate) are removed from the timepiece movement of FIG. 2. FIG. 4 is a schematic plan view illustrating an example in which an antenna substrate is disposed inside a timepiece module and outside a display vehicle, and illustrates an example in which one date indicator is applied as a display vehicle. FIG. 4 is a schematic plan view showing an example in which an antenna substrate is provided inside a timepiece module and is disposed outside a display vehicle, and a date wheel representing the first digit of date numbers as a display vehicle. An example is shown in which the date indicator representing the tens digit is applied. FIG. 2 is a cross-sectional view corresponding to FIG. 1 showing an electronic timepiece having a configuration without a date wheel holder. FIG. 7 is a perspective view corresponding to FIG. 2 showing the timepiece module in FIG. 6. FIG. 2 is a sectional view corresponding to FIG. 1 illustrating an example of a configuration in which a solar cell exerts a function of holding a date wheel. FIG. 4 is an exploded perspective view corresponding to FIG. 3 showing an electronic timepiece having a configuration in which a date wheel holder also serves as an antenna substrate. FIG. 10 is a sectional view of the electronic timepiece shown in FIG. 9 corresponding to FIG. 1. FIG. 2 is a cross-sectional view corresponding to FIG. 1, showing a cross section in a thickness direction of an electronic timepiece in which an opening is formed in at least a part of a portion of a circuit board overlapping an antenna pattern of an antenna board. It is the top view which looked at the timepiece module except the date wheel holder from the dial side. FIG. 13 is a bottom view of the timepiece module illustrated in FIG. 12 when viewed from the back cover side while being rotated around an illustrated vertical axis. FIG. 1 is a cross-sectional view of a circuit board in which at least a portion (for example, a GND (ground) pattern) functioning as a reference potential for the antenna pattern is not formed on at least a part of a portion overlapping with the antenna pattern of the antenna substrate. FIG.

  Hereinafter, specific embodiments of an electronic timepiece according to the invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a cross section of a surface including a thickness direction t of an electronic timepiece 1 which is a wristwatch as one embodiment of an electronic timepiece according to the present invention. FIG. 2 shows a timepiece movement 10 in the electronic timepiece 1 of FIG. FIG. 3 is an exploded perspective view showing a state where the date wheel holder 15 and the antenna substrate 32 (second substrate) are removed from the timepiece movement 10 of FIG.

<Structure>
The illustrated electronic timepiece 1 is a wristwatch that is worn on a wrist of a human body using a band (not illustrated). As shown in FIG. 1, the electronic timepiece 1 includes an outer case 5, a timepiece movement 10, a receiving unit 30, and a time display unit 50.

  The outer case 5 includes a bezel 2, a body 3, and a back cover 4. The bezel 2 and the body 3 are formed of a metal material (conductive material) such as, for example, stainless steel. Note that the outer case 5 may be formed of a non-conductive material such as ceramics, glass, and resin. The bezel 2 and the body 3 are overlapped in the thickness direction t of the electronic timepiece 1 to form a short cylindrical outer peripheral portion. The back cover 4 closes one end (the lower end face in FIG. 1) of the short cylinder formed by the outer peripheral portion. Thereby, the outer case 5 forms a short columnar space inside.

  A windshield 6 is fitted to the other end (the upper end face in FIG. 1) of the outer case 5, and the windshield 6 closes the other end. A time display unit 50, a clock movement 10, and a receiving unit 30 are arranged in a space inside the outer case 5 closed by the windshield 6.

  The time display unit 50 is arranged on the side close to the windshield 6 in the closed space. The time display unit 50 indicates the time character (index) 52 provided on the front surface (the surface facing the windshield 6) of the dial 51 by the hands of the hour hand 55, the minute hand 56 and the second hand 57. Is displayed. That is, the electronic timepiece 1 is a so-called analog timepiece. The dial 51 has optical transparency.

  In FIG. 1, the hour hand 55, the minute hand 56, and the second hand 57 are described as being fixed to a single shaft 54, but this is for the purpose of simplifying the illustration and the following description. Actually, the axis on which the hour hand 55 is fixed, the axis on which the minute hand 56 is fixed, and the axis on which the second hand 57 is fixed exist separately.

  The shaft 54 is rotationally driven by the clock movement 10, whereby the hands (hour hand 55, minute hand 56, second hand 57) fixed to the shaft 54 rotate to display the time.

  The time display unit 50 includes a dial ring 53 that covers the outer peripheral edge of the dial 51 and the inner peripheral surface of the bezel 2 of the outer case 5 on the front side of the dial 51. The dial ring 53 is a member that presses the peripheral edge of the dial 51 and holds the dial 51 at a predetermined position. The dial 53 is formed in a substantially annular shape around the center axis of the timepiece 1 and has a function of decorating the time display unit 50.

  The watch movement 10 is arranged on the side close to the back cover 4 in the closed space. The timepiece movement 10 includes a battery 11 and a timepiece module 12. The battery 11 is used for charging electric energy generated by a solar cell 40 described later, supplying the charged electric energy to the timepiece module 12, and driving a motor and the like of the timepiece module 12.

  The timepiece module 12 includes a main plate 13, a motor and a gear train supported by the main plate 13, a date wheel 14 driven to rotate by the motor and the gear wheel train, and a date wheel holder 15 ( (Vehicle holding). The shaft 54 to which the hour hand 55, the minute hand 56 and the second hand 57 are fixed also constitutes a part of the timepiece module 12.

  The base plate 13 is a member that supports a motor, a gear train, and the like, and is disposed on a side close to the battery 11. The motor is driven to rotate by electric energy supplied from the battery 11. The gear train transmits the rotational driving force generated by the motor to the shaft 54 and the date indicator 14 while increasing and decreasing the rotational driving force. The configuration of the timepiece module 12 includes, in addition to the gear train, for example, a light detection device used for a hand position detection function for detecting the positions of hands such as an hour hand 55 and a minute hand 56, and a circuit board for hand movement control. included.

  The date indicator 14 is an annular member that rotates similarly to the hands, and is an example of a display wheel. The date wheel 14 rotates according to the rotation of the gear train because the teeth of the gear train mesh with the teeth formed on the inner peripheral edge of the ring. The date dial 14 is arranged in the timepiece movement 10 in proximity to the dial 51. In other words, the date dial 14 is arranged on the back side of the dial 51 and close to the dial 51.

  As shown in FIG. 2, a plurality of numbers “1”, “2”,..., “31” representing dates are displayed on the date indicator 14 in a circumferential direction. By rotating the date indicator 14 so as to feed the date by one per day, one date displayed on the date indicator 14 is superimposed on a window (not shown) formed in the dial 51. Then, the displayed date (number) is visually recognized through a window. In addition, the solar cell 40 described later also has an opening in a region overlapping the small window of the dial 51 in plan view. The date indicator 14 may be a member formed by overlapping an annular member having teeth formed on the inner peripheral edge with an annular member having a plurality of numbers representing dates.

  A date wheel holder 15 is disposed inside the date wheel 14 (in the radial direction from the inner peripheral edge). The date wheel holder 15 falls off to the windshield 6 side in the thickness direction t due to the configuration in which the outer peripheral edge of the date wheel holder 15 contacts a part of the inner peripheral edge of the date wheel 14 in the thickness direction t of the electronic timepiece 1. This is a member that prevents As shown in FIG. 3, the date indicator holder 15 is fixed to the main plate 13 or the like by, for example, three screws 82. The date wheel holder 15 is an example of a dielectric (insulator).

  A solar cell 40 is arranged between the date dial 14 and the dial 51 in the thickness direction t of the electronic timepiece 1. The solar cell 40 irradiates the dial 51 from the side of the windshield 6 and receives light, such as sunlight, transmitted through the dial 51 having optical transparency to generate power. Electric energy generated by the solar cell 40 is stored in the battery 11. Therefore, the electronic timepiece 1 is a so-called solar cell timepiece.

  The receiving unit 30 receives a radio wave emitted from an external device. Therefore, the electronic timepiece 1 is also a so-called radio timepiece having a communication function. The radio wave received by the electronic timepiece 1 is based on, for example, Bluetooth (registered trademark), which is one of short-range wireless communication standards for digital devices. The receiving unit 30 includes a circuit board 31 (first board), an antenna board 32 (second board), and a conductive member 33.

  The antenna substrate 32 includes an antenna pattern 34 (antenna) formed of linear wiring, which is a substantial part that functions as an antenna for receiving a radio wave, and a substantial part that functions as this antenna. (The antenna pattern 34). The antenna may be a conductive plate-shaped one in which the antenna pattern 34 and the substrate portion are integrated.

  In the antenna substrate 32, the antenna pattern 34 is formed on the lower surface (the surface facing the back cover 4) of the antenna substrate 32. The circuit board 31 has a feed circuit 31c for feeding power to the antenna of the antenna board 32 and a GND pattern (ground pattern) 31b. The conduction member 33 is a member that electrically connects (conducts) the power supply circuit 31c and the antenna pattern 34.

  A matching circuit for impedance matching may be provided between the antenna pattern 34 and the power supply circuit 31c. In particular, regarding the connection between the conductive member 33 and the power supply circuit 31c, it is preferable that the connection be made of a microstrip line.

  The circuit board 31 is disposed between the base plate 13 and the back cover 4 of the timepiece movement 10 in the thickness direction t of the electronic timepiece 1 and is fixed to the base plate 13 and the like. The antenna substrate 32 is disposed on the lower surface (the surface facing the back cover 4) of the date wheel holder 15.

  That is, the antenna board 32 is arranged inside the date wheel 14 in the radial direction. The antenna substrate 32 is fixed to the conductive member 33 by one screw 81 as shown in FIG. At this time, the antenna pattern 34 formed on the lower surface of the antenna substrate 32 and the conductive member 33 are fixed in contact with each other.

  By fixing the antenna pattern 34 and the conductive member 33 in contact with each other, it is possible to reduce the influence on the antenna reception sensitivity due to manufacturing variations. Further, the conductive member 33 may be a conductive pin formed of a conductive material.

  Further, as shown in FIG. 1, at least a part of the antenna substrate 32 is arranged at a position overlapping with the date dial 14 in the thickness direction t of the electronic timepiece 1. Further, the antenna substrate 32 is arranged closer to the back cover 4 than the date wheel holder 15 in the thickness direction t. As described above, the antenna substrate 32 is disposed inside the timepiece movement 10 (the area inside the outer shape of the space occupied by the timepiece movement 10 in the radial direction and the thickness direction t).

  The conductive member 33 is a member that electrically connects (conducts) the antenna pattern 34 of the antenna substrate 32 and the power supply circuit 31c of the circuit board 31, and the lower surface side of the conductive member 33 is in contact with the power supply circuit 31c. Fixed. The antenna pattern 34 supplied from the power supply circuit 31 c via the conductive member 33 receives the Bluetooth radio wave, and the radio wave received by the antenna pattern 34 is processed by the circuit board 31 through the conductive member 33.

<Action and effect>
In the electronic timepiece 1 configured as described above, as shown in FIG. 1, at least a part of the antenna substrate 32 is arranged at a position overlapping the date wheel 14 in the thickness direction t of the electronic timepiece 1. In addition, in the thickness direction t of the electronic timepiece 1, the thickness of the electronic timepiece 1 can be reduced as compared with the case where the display wheel such as the date wheel 14 and the antenna substrate 32 are arranged at positions not overlapping.

  The electronic timepiece 1 does not protrude from the timepiece movement 10 because the antenna substrate 32 is disposed inside the timepiece module 12 constituting the timepiece movement 10. In the electronic timepiece 1, the antenna substrate 32 is arranged so as not to overlap with the date dial 14 in a plan view of the electronic timepiece 1. Therefore, the antenna substrate 32 is arranged in a range other than the range where the date wheel 14 is arranged in a plan view. can do.

  FIGS. 4 and 5 are schematic views in plan view showing an example in which the antenna substrate 32 is located inside the watch module 12 and outside the display wheel (outside in the radial direction of the electronic watch 1 in plan view). FIG. 4 shows an example in which one date wheel 14 is applied as a display vehicle, and FIG. 5 shows date wheels 14 and 10 which represent the first digit and tenth digit, respectively, as the display vehicle. 14 'are shown below.

  In the electronic timepiece according to the present invention, the antenna member does not have to be arranged inside the display wheel, and as shown in FIGS. May be arranged outside the. That is, the electronic timepiece according to the present invention may be any type as long as at least a part of the antenna member overlaps the display member in the thickness direction of the electronic timepiece.

  In the electronic timepiece 1, the solar cell 40 is disposed on the opposite side of the back cover 4 with respect to the antenna pattern 34 in the thickness direction t, and a dielectric (insulator) is provided between the solar cell 40 and the antenna pattern 34. One day, a wheel holder 15 is arranged. Therefore, in an electronic timepiece having a structure assuming that the date wheel holder 15 does not exist, even if a situation occurs in which the solar cell 40, which is a semiconductor, and the antenna pattern 34, which is a conductor, come into contact with each other to cause a short circuit, In the electronic timepiece 1, the date indicator holder 15 prevents contact between the solar cell 40 and the antenna pattern 34, so that a short circuit can be prevented.

  Since the date indicator holder 15 is formed of a dielectric (insulator) material, the effect of shortening the wavelength of the dielectric contributes to downsizing of the antenna electrode.

  In addition, the electronic timepiece according to the present invention is not limited to the one in which the date indicator 15 is disposed between the solar cell 40 and the antenna pattern 34, and the date indicator 15 is disposed between the solar cell 40 and the antenna pattern 34. Alternatively, another dielectric may be provided, and the dielectric may prevent contact between the solar cell 40 and the antenna pattern 34 to prevent a short circuit.

  FIG. 6 is a sectional view corresponding to FIG. 1 showing the electronic timepiece 1 having no date wheel holder 15, FIG. 7 is a perspective view corresponding to FIG. 2 showing the timepiece module 12 in FIG. 6, and FIG. FIG. 2 is a cross-sectional view corresponding to FIG. 1 illustrating an example of a configuration that exerts a function of a presser 15. As shown in FIGS. 6 and 7, the electronic timepiece 1 may not include the date wheel holder 15 shown in FIGS.

  As shown in FIG. 8, a protruding portion 40 a protruding toward the back cover 4 is provided on a surface of the solar cell 40 facing the back cover 4, and the protruding portion 40 a functions as the date wheel holder 15. It can also be adopted as a configuration. Further, when the solar cell 40 is not provided, a protrusion similar to the above-described protrusion 40a is provided on the surface of the dial 51 facing the back cover 4, and the protrusion functions as the date wheel holder 15. It can also be adopted as a configuration.

  6 and 8, the illustration of the power supply circuit 31c and the GND pattern 31b is omitted, but is the same as that of FIG.

  In the case of the electronic timepiece 1 without the date wheel holder 15, the antenna substrate 32 is arranged so as not to protrude from the surface of the date wheel 14 opposite to the back cover 4 (the surface facing the dial 51). Is preferred. In the electronic timepiece 1 of the preferred embodiment, since the antenna substrate 32 is disposed so as to be retracted from the surface of the date wheel 14 opposite to the back cover 4, the antenna substrate 32 is housed inside the timepiece module 12. can do.

  In the electronic timepiece 1, since the antenna pattern 34, which is a portion that substantially functions as an antenna, is formed in a linear shape, the area in a plan view can be smaller than that of the planar antenna pattern. . Therefore, in plan view of the electronic timepiece 1, the overlapping area between the antenna pattern 34 and the solar cell 40 as a semiconductor can be made smaller than the overlapping area between the planar antenna pattern and the solar cell.

  As a result, the electronic timepiece 1 can reduce the stray capacitance (parasitic capacitance) that increases as the overlapping area in plan view increases, as compared with an electronic timepiece having a planar antenna pattern. It is possible to reduce deterioration of the receiving sensitivity of the antenna due to the current loss of the stray capacitance.

  The electronic timepiece according to the present invention is not limited to one in which the entire antenna pattern 34 overlaps the solar cell 40 in a plan view, and may be one in which a part of the antenna pattern 34 overlaps the solar cell 40. However, the antenna pattern 34 does not have to overlap the solar cell 40 at all. Furthermore, the electronic timepiece according to the present invention may not include the solar cell 40.

  Further, the electronic timepiece according to the present invention is not limited to the electronic timepiece having the second substrate on which the linear antenna pattern is formed, but includes the second substrate on which the planar antenna pattern is formed. It may be.

  Further, in the electronic timepiece according to the present invention, the antenna of the second substrate is not limited to one in which the antenna pattern is formed on the substrate by wiring, and the antenna of the second substrate is a so-called patch antenna (planar antenna). Or an inverted F-type antenna. Further, the antenna of the second substrate may be configured by an antenna substrate 32 having a bar antenna or a chip antenna mounted on the substrate portion.

  In the electronic timepiece according to the present invention, the radio wave received by the antenna of the antenna member may not be based on the Bluetooth standard. For example, a so-called Wi-Fi (registered trademark) radio wave or NFC (Near Field Communication) may be used. Wireless communication), a long wave radio wave including standard time information, a radio wave emitted from a GPS satellite, or the like may be used.

  In the electronic timepiece 1, the linear antenna pattern 34 of the antenna substrate 32 extends in a direction different from the direction in which the body 3 of the outer case 5 extends (circumferential direction). That is, the distance between the antenna pattern 34 and the trunk 3 of the outer case 5 is not constant over the entire length, and the antenna pattern 34 does not extend in the circumferential direction concentric with the trunk 3.

  Here, if the antenna pattern 34 extends in the circumferential direction concentric with the direction in which the body 3 extends, a stray capacitance (parasitic capacitance) is generated between the antenna pattern 34 and the body 3. In 1, since the antenna pattern 34 extends in a direction different from the direction in which the body 3 extends, no stray capacitance is generated between the antenna pattern 34 and the body 3 or the generation thereof is suppressed. Thus, the electronic timepiece according to the present invention can reduce the deterioration of the receiving sensitivity of the antenna due to the stray capacitance.

  In particular, when the second substrate is a bar antenna, the shape of the bar antenna is often formed in a straight line or an arc. Even in the case of such a linear or arc-shaped bar antenna, the electronic timepiece according to the present invention has a configuration in which the direction in which the bar antenna extends is different from the direction in which the outer case extends. Generation of capacity can be suppressed.

  In the electronic timepiece according to the present invention, the antenna on the second substrate is not limited to the antenna extending in a direction different from the circumferential direction of the outer case.

  9 is an exploded perspective view corresponding to FIG. 3 showing the electronic timepiece 1 in which the date wheel holder 15 also serves as the antenna substrate 32, and FIG. 10 is a sectional view of the electronic timepiece 1 shown in FIG. 9 corresponding to FIG. . The electronic timepiece 1 shown in FIGS. 9 and 10 is the same as the electronic timepiece 1 of the embodiment shown in FIG. 1 except that the date indicator holder 15 also serves as the antenna substrate 32. Is the same as In FIG. 10, the power supply circuit 31c and the GND pattern 31b are not shown, but are formed in the same manner as in FIG.

  In the electronic timepiece 1 shown in FIG. 10, a linear antenna pattern 34 is formed on the lower surface of the date wheel holder 15 (the surface facing the back cover 4). Thus, unlike the electronic timepiece 1 shown in FIG. 1, it is not necessary to provide a substrate portion for supporting the antenna pattern 34 separately from the date wheel holder 15, thereby simplifying the configuration and reducing the thickness. it can.

  In the electronic timepiece 1, the antenna substrate 32 may include a circuit having another function different from the function of the antenna for receiving a radio wave. As such another function, for example, a position detecting circuit of a hand such as an hour hand 55, a minute hand 56 and a second hand 57 can be applied. Thus, circuits relating to a plurality of functions can be integrated into one. As another example, at least a part of the receiving circuit included in the receiving unit 30 can be provided on the antenna substrate 32.

  Further, in the electronic timepiece 1, the antenna pattern 34 of the antenna substrate 32 is arranged so as not to overlap with the battery 11 which is a driving source of the electronic timepiece 1 in a plan view of the electronic timepiece 1. Since the battery 11 is a conductor, if the battery 11 is close to the antenna pattern 34, the reception sensitivity of the radio wave may be reduced. However, in the electronic timepiece 1, the battery 11 is separated from the antenna pattern 34, and Since the battery 11 does not overlap with the antenna pattern 34 in a plan view of the electronic timepiece, there is no possibility that the reception sensitivity of the radio wave is reduced.

  In the electronic timepiece 1, the size of the electronic timepiece 1 in a plan view is smaller than that of the circuit board 31 in the antenna substrate 32, so that a structure in which the antenna substrate 32 is housed inside the timepiece movement 10 can be realized. The electronic timepiece 1 can be reduced in thickness.

  In the electronic timepiece 1, when the electronic timepiece 1 is viewed in a plan view, since the antenna substrate 32 is arranged inside the date indicator 14 formed in an annular shape in the radial direction, the timepiece movement 10 can be reduced in diameter.

  In the electronic timepiece 1, as shown in FIG. 3, the winding stem 90 is set so that the 3 o'clock direction of the dial 51 (see FIG. (In the direction of 90 degrees when the angle of the circumference is set to 360 degrees and the angle in the clockwise direction is set to positive). Therefore, metal parts such as crowns and stamens are concentrated on the portion of the timepiece module 12 in the direction of 3 o'clock (direction of 90 degrees), similarly to a general wristwatch.

  In the electronic timepiece 1, the conductive member 33 for feeding power to the antenna pattern 34 of the antenna substrate 32 is provided in a range α in a clockwise direction of 180 degrees or more and 360 degrees or less, and metal components are concentrated 90. It is located far away from the vicinity. In addition, the antenna substrate 32 and the motor are arranged at positions where they do not overlap in the cross-sectional view (in the thickness direction of the electronic timepiece 1), and no motor is arranged around the feeding part of the antenna. In general, the conducting member 33 serving as a power feeding portion of the antenna has a large magnetic field because the flowing current is large. If a metal component is arranged near the conductive member 33, the metal component is affected by the magnetic field, and the reception sensitivity of the antenna is reduced.

  On the other hand, in the electronic timepiece 1, since the conductive member 33 is disposed far away from the metal component, a decrease in the receiving sensitivity of the antenna is prevented or suppressed.

  The electronic timepiece according to the present invention is not limited to the electronic timepiece in which the conductive member 33 is provided in the range α in the clockwise direction of 180 degrees or more and 360 degrees or less.

  FIG. 11 is a cross-sectional view in a thickness direction t of the electronic timepiece 1 in which an opening 31a is formed in at least a part W of a portion of the circuit board 31 overlapping with the antenna pattern 34 of the antenna board 32, corresponding to FIG. FIG. 12 is a plan view of the timepiece module 12 excluding the date indicator holder 15 as viewed from the dial 51, and FIG. 13 is a view of the timepiece module 12 shown in FIG. The bottom views seen from the back cover 4 side after being rotated are shown.

  FIG. 14 illustrates a circuit board 31 in which at least a portion W of a portion overlapping with the antenna pattern 34 of the antenna substrate 32 does not have a portion functioning as a reference potential for the antenna pattern 34 (for example, a GND pattern 31b). FIG. 2 is a sectional view corresponding to FIG. 11 and 14, the power supply circuit 31c is not shown, but is formed in the same manner as in FIG.

  As shown in FIGS. 11, 12, and 13, the electronic timepiece 1 has an opening 31a formed in at least a part W of a portion of the circuit board 31 overlapping the antenna pattern 34 of the antenna substrate 32 in a plan view of the electronic timepiece 1. 14, or at least a portion W of a portion of the circuit board 31 overlapping the antenna pattern 34 of the antenna substrate 32 in a plan view of the electronic timepiece 1 as shown in FIG. It is preferable that a portion (for example, the GND pattern 31b) is not formed (only a portion other than a portion functioning as a reference potential for the antenna pattern 34) is formed.

  If a portion (for example, GND pattern 31b) that functions as a reference potential for the antenna pattern 34 is formed in a portion of the circuit board 31 that overlaps with the antenna pattern 34 of the antenna substrate 32, the portion that functions as the reference potential is sandwiched. Thus, an image antenna symmetrical to the antenna pattern 34 is formed at a position symmetrical to the antenna pattern 34. Then, in the image antenna, since the direction of the current in the lateral direction (the direction in the plane of the antenna pattern 34) is opposite to that of the antenna pattern 34, the magnetic field is canceled and the receiving sensitivity is reduced.

  On the other hand, an opening 31a is formed in at least a part W of the circuit board 31 overlapping the antenna pattern 34 of the antenna board 32, or a portion functioning as a reference potential for the antenna pattern 34 (for example, a GND pattern 31b). If the antenna pattern is not formed, no image antenna is formed. Therefore, it is possible to avoid a decrease in the reception sensitivity of the radio wave due to the antenna pattern 34.

  The electronic timepiece 1 is provided with a date wheel 14 exhibiting a calendar function and the like, but is provided with a display wheel in which a plurality of days and city names are displayed in a circumferential direction in place of the date wheel 14. One of the day of the week and the city name of the display car is superimposed on a window formed on the dial 51 of the dial 51, and the day and the city name displayed through the window are visually recognized. Is also good.

  Further, the electronic timepiece 1 has been described as a wristwatch worn on an arm via a belt, but the electronic timepiece according to the present invention is not limited to a wristwatch. The electronic timepiece according to the present invention may be, for example, a table clock, a wall clock, a pocket watch, or the like. Further, the electronic timepiece according to the present invention is, for example, a portable information terminal device such as various cameras, game machines, mobile phones (including smartphones), PDAs (Personal Digital Assistants), notebook (laptop) type personal computers, etc. The present invention may be applied to electronic devices including home appliances and automobiles.

DESCRIPTION OF SYMBOLS 1 Electronic timepiece 5 Outer case 10 Timepiece movement 14 Date indicator 15 Date indicator 31 Circuit board (first board)
32 Antenna board (second board)
33 Conductive member 34 Antenna pattern (antenna)
51 Dial t Thickness direction

Claims (9)

An outer case having a back cover,
A watch movement having a display car,
A first substrate on which a GND pattern and a power supply circuit are formed, which is arranged on the side of the back cover of the timepiece module constituting the timepiece movement;
A second substrate on which an antenna is formed, at least a part of which is arranged at a position overlapping the display wheel in a thickness direction of the timepiece;
An electronic timepiece including: a conductive member that connects the power supply circuit and the antenna. A solar cell is arranged on the side opposite to the back cover with respect to the antenna,
The electronic timepiece according to claim 1, wherein a dielectric is disposed between the antenna and the solar cell. The antenna is a linear antenna,
The electronic timepiece according to claim 1, wherein at least a part of the linear antenna is arranged at a position overlapping the solar cell in a plan view of the timepiece.   4. A plan view of the timepiece, wherein, in the first substrate, a portion overlapping the antenna is open or only a portion other than a portion functioning as a reference potential for the antenna is formed. An electronic timepiece according to any one of the preceding claims.   The electronic timepiece according to any one of claims 1 to 4, wherein the second substrate is disposed inside the display wheel in a plan view of the timepiece.   The electronic timepiece according to any one of claims 1 to 5, wherein the second substrate is arranged so as not to overlap with the display wheel in plan view of the timepiece.   The electronic timepiece according to claim 1, wherein the second substrate includes a circuit having a function other than communication.   The electronic timepiece according to any one of claims 1 to 7, wherein the second substrate also serves as a display wheel holder.   9. The electronic timepiece according to claim 1, wherein the second substrate is arranged so as not to protrude from a surface of the display wheel opposite to the back cover. 10.