JP2022148391A - Electronic watch - Google Patents

Abstract

An object of the present invention is to provide an electronic timepiece capable of suppressing an increase in the number of parts while stabilizing reception performance. Kind Code: A1 An electronic timepiece includes a time display portion having hands and a dial, an antenna 200 arranged around the time display portion and having a feed element and a ground element formed on an annular dielectric base material, and hands. A base plate 100 to which a driving motor is attached, a magnetic shield plate 160 that overlaps the motor in a plan view seen from a direction perpendicular to the surface of the dial and is electrically connected to the ground element, and a power supply terminal that is connected to the power supply element. and a ground terminal connected to the ground element via a magnetic shield plate. [Selection drawing] Fig. 4

Description

The present invention relates to an electronic timepiece having a ring-shaped antenna.

Patent Document 1 discloses an antenna with a built-in antenna in which an antenna pattern made of a conductive material is formed on an annular dielectric base material, and an annular ground plate made of a conductive material is arranged between the base plate and the ground plane. A clock is disclosed.

JP 2014-62846 A

In Patent Document 1, since a dedicated ground plate is provided separately from the antenna, the number of parts increases, and there are cases where the distance between the antenna pattern and the ground plate cannot be kept constant due to manufacturing errors. , there is a problem that reception performance is not stable. Therefore, there has been a demand for a structure that does not increase the number of parts while stabilizing the reception performance.

An electronic timepiece according to the present disclosure includes a time display unit including hands and a dial, an antenna disposed around the time display unit and having a feed element and a ground element formed on an annular dielectric base material, and the hands. a main plate to which a driving motor is attached; a magnetic shield plate that overlaps the motor in a plan view seen in a direction perpendicular to the surface of the dial and is electrically connected to the ground element; A circuit board having a power supply terminal and a ground terminal electrically connected to the ground element through the antimagnetic plate is provided.

1 is a schematic diagram showing an electronic timepiece according to a first embodiment of the invention; FIG. 1 is a plan view showing the electronic timepiece of the first embodiment; FIG. 1 is a cross-sectional view showing an electronic timepiece according to a first embodiment; FIG. 1 is an exploded perspective view showing essential parts of the electronic timepiece of the first embodiment; FIG. FIG. 2 is a plan view of the circuit board of the movement of the first embodiment as seen from the back cover side; It is the top view which looked at the circuit presser of the movement of 1st Embodiment from the back cover side. It is the top view which looked at the 1st magnetic-resistant board of the movement of 1st Embodiment from the cover-glass side. It is a sectional view showing the important section of the movement of a 1st embodiment. 2 is a block diagram showing the circuit configuration of the electronic timepiece of the first embodiment; FIG. It is a schematic perspective view showing the surface side of an antenna and a first magnetic shield. It is a schematic perspective view showing the back side of the antenna. It is a figure which shows the attachment structure of an antenna. It is a figure which shows the attachment structure of an antenna. FIG. 10 is a characteristic diagram showing a radiation pattern of an antenna; FIG. 10 is a plan view showing an electronic timepiece according to a second embodiment; FIG. 5 is a cross-sectional view showing an electronic timepiece according to a second embodiment; It is a figure which shows the attachment structure of the antenna of a modification. FIG. 11 is a cross-sectional view showing an electronic timepiece of a modified example;

[First embodiment]
An electronic timepiece according to a first embodiment of the present disclosure will be described below with reference to the drawings.
1 is a schematic diagram showing an electronic timepiece 10, FIG. 2 is a plan view of the electronic timepiece 10 viewed from the surface side, FIG. 3 is a cross-sectional view showing an outline of the electronic timepiece 10, and FIG. 4 is an electronic timepiece. 10 is an exploded perspective view of the main part of FIG.
The electronic timepiece 10 of the present embodiment receives satellite signals from positioning information satellites S such as GPS satellites and quasi-zenith satellites orbiting the earth in a predetermined orbit to obtain satellite time information. It is a wristwatch that corrects internal time information. GPS is an abbreviation for Global Positioning System. A GPS satellite is a navigation satellite that orbits the earth in a predetermined orbit, and superimposes a navigation message on a radio wave of 1.57542 GHz and transmits it to the ground. In the following description, the 1.57542 GHz radio wave on which the navigation message is superimposed will be referred to as a satellite signal. The satellite signal is circularly polarized with right hand polarization.

The electronic timepiece 10 includes an exterior case 30, a cover glass 33, and a metal back cover 34, as shown in FIGS. The exterior case 30 is configured by fitting a metal bezel 32 to a metal cylindrical case 31 . In the following description, for each component of the electronic timepiece 10, the cover glass 33 side is defined as the front surface or top surface, and the back cover 34 side is defined as the back surface or bottom surface.
On the side surface of the exterior case 30, the A button 17A is provided at the 8 o'clock position with respect to the plane center of the dial 11, the B button 17B is provided at the 10 o'clock position, and the B button 17B is provided at the 2 o'clock position. A C button 17C is provided, a D button 17D is provided at the 4 o'clock position, and a crown 14 is provided at the 3 o'clock position.

Inside the exterior case 30, as shown in FIGS. 3 and 4, there are a dial ring 40 attached to the inner periphery of the bezel 32, an antenna 200, a light-transmissive dial 11, hands 21 and 22. , 23, 71, 81, 91, a solar panel 50, a ring-shaped calendar wheel 16, a first magnetic shielding plate 160, a main plate 100, a circuit board 120, a second magnetic shielding plate 170, and a circuit holder 122. , and the drive mechanism 140 are arranged.
A pointer shaft 25 is arranged in the plane center of the dial 11 . The pointer shaft 25 has triple pointer shafts 25A, 25B, and 25C. The pointer shafts 25A, 25B, 25C pass through the plane center of the dial 11 and are provided along the front and back directions, ie, along the thickness direction of the electronic timepiece 10, and the pointers 21, 22, 23 are attached.

The dial 11 is provided with a circular first small window 70 and a pointer 71 in the 2 o'clock direction with respect to the center of the plane, and a circular second small window 80 and a circular pointer 81 in the 10 o'clock direction. A circular third small window 90 and hands 91 are provided in the 6 o'clock direction, and a rectangular calendar small window 15 is provided in the 4 o'clock direction. The dial 11, the hands 21, 22, 23, the first small window 70, the second small window 80, the third small window 90, the calendar small window 15, etc. are seen through the cover glass 33 attached to the opening of the bezel 32. and is visible.

The dial 11 is a circular plate that displays the time inside the exterior case 30, is made of a light-transmitting synthetic resin material, and has pointers 21, 22, 23, etc. between it and the cover glass 33. , are arranged inside the dial ring 40 . The dial 11 of this embodiment is made of polycarbonate.
A solar panel 50 for photovoltaic power generation is arranged on the rear surface of the dial 11 . The solar panel 50, as also shown in FIG. 4, is a circular flat plate in which a plurality of solar cells that convert light energy into electrical energy are connected in series.
The dial 11 and the solar panel 50 are arranged in an overlapping manner, and the outer circumference thereof is arranged on the lower surface of the inner circumference of the dial ring 40 as shown in FIG. That is, the dial ring 40 covers the outer edges of the dial 11 and the solar panel 50 . Therefore, the dial ring 40 functions as a parting member that cuts off the outer periphery of the dial 11 , and the diameter of the inner peripheral opening of the dial ring 40 is the parting diameter of the dial 11 .
The dial 11 and the solar panel 50 are formed with holes through which the pointer shafts 25A, 25B, 25C, the pointer shaft 26 of the pointer 71, the pointer shaft 27 of the pointer 81, and the pointer shaft 28 of the pointer 91 penetrate. In addition, an opening for a small calendar window 15 is formed.
A calendar wheel 16 and a date wheel 29 attached to a shaft 29A are arranged on the back side of the solar panel 50. - 特許庁The calendar wheel 16 can be visually recognized from the small calendar window 15.例文帳に追加

A first anti-magnetic plate 160 is arranged on the back side of the calendar wheel 16 , and a main plate 100 is arranged on the back side of the first anti-magnetic plate 160 . The ground plate 100 is made of a synthetic resin material, and has a through hole 105 in which the antenna feeding pin 240 is arranged.

5 and 6 are plan views showing the movement seen from the back cover side, FIG. 7 is a plan view showing the movement seen from the cover glass side, and FIG. 8 is a cross-sectional view of the essential parts of the movement. 5 is a plan view showing the circuit board 120 exposed by removing the second magnetic shield 170 and the circuit holder 122, and FIG. 6 is a plan view showing the state where the second magnetic shield 170 and the circuit holder 122 are attached. . FIG. 7 is a plan view showing a state in which the dial 11, the solar panel 50, and the calendar wheel 16 are removed to expose the first antimagnetic plate 160. FIG. FIG. 8 is a cross-sectional view showing the fixing structure of the motor, with the circuit holder 122 arranged closer to the back cover 34 than the motors 141 to 145 facing upward, and the dial 11 facing downward.
A drive mechanism 140 is attached to the base plate 100 and covered with a circuit board 120 from the back side. The drive mechanism 140 has a step motor and a wheel train such as gears. In this embodiment, a first motor 141 that drives the pointer 81 that is the second hand, a second motor 142 that drives the pointer 22 that is the minute hand and the pointer 23 that is the hour hand, and the pointer 21 that is the chronograph second hand and the chronograph minute hand. , a fourth motor 144 that drives a pointer 91 that serves both as an indicator hand and a chronograph hour hand, and a fifth motor 145 that drives the calendar wheel 16 .
The configuration of each of the motors 141 to 145 will be described using the second motor 142 as an example. As shown in FIGS. 5 and 8, the second motor 142 is a step motor including a coil 152 wound around a core 151, a stator 153, and a rotor 154. The second motor 142 further includes a substrate seat 155 superimposed on the core 151 and a motor substrate 156 to which the coil 152 is electrically connected. The other motors 141, 143-145 have similar configurations. The main plate 100 and the first anti-magnetic plate 160 are formed with holes through which the pointer shafts 25A, 25B, 25C, 26, 27, 28 and the shaft 29A driven by the motors 141-145 pass.
The dial 11 and hands 22, 23, and 81, which are at least hour, minute, and second hands, constitute a time display unit for displaying the time.

The circuit board 120 arranged on the back side of the main board 100 includes a GPS receiver 300 and a control display 400, as shown in FIGS. Further, the circuit board 120 is formed with openings in which the motor coils of the motors 141 to 145 are arranged and cutouts in which the secondary battery 130 is arranged. Further, on the surface of the circuit board 120, as shown in FIGS. 3 and 4, a feeding terminal 120A is formed with which the antenna feeding pin 240 abuts.
The GPS receiving section 300 and the control display section 400 are composed of integrated circuits and attached to the back surface of the circuit board 120 . The secondary battery 130 is composed of a lithium ion battery or the like, and is charged with power generated by the solar panel 50 .

A circuit holder 122 is provided on the back side of the circuit board 120 with a second magnetic shield plate 170 interposed therebetween. The circuit retainer 122 is made of a metal plate and, as shown in FIG. and screwed to the base plate 100 . Further, on the rear surface of the circuit board 120, as shown in FIG. 8, a ground terminal 120B is formed in contact with the fixing piece 124 of the circuit retainer 122. As shown in FIG.
As a result, the ground pattern of the circuit board 120 is electrically connected to the back cover 34 made of metal via the ground terminal 120B, the fixing piece 124 of the circuit retainer 122, and the conductive spring portion 123. As shown in FIG.
The second magnetic shielding plate 170 and the circuit retainer 122 are formed in a shape that does not overlap the secondary battery 130 in a plan view. 130 can be replaced. Here, "planar view" means a state viewed from a direction along the pointer shaft 25, that is, a first direction perpendicular to the surface of the dial 11. As shown in FIG. A side view means a state viewed from a second direction perpendicular to the first direction.

[magnetic shield]
Next, the anti-magnetic plate will be explained.
Each motor 141 to 145 of the drive mechanism 140 is sandwiched between a first magnetic shield plate 160 and a second magnetic shield plate 170 . In recent years, high-performance magnets have come to be used in many cases for mobile terminals such as smartphones, and anti-magnetism is also required for wristwatches. For this reason, in order to detour the external magnetic field and prevent the stepping motor from malfunctioning, the first magnetic shielding plate 160 and the second magnetic shielding plate 170 made of a high magnetic permeability material such as pure iron are mounted on the motors 141 to 170 in plan view. 145.
It should be noted that the coil portions of the motors 141 to 145 are less susceptible to the influence of external magnetic fields, so they do not necessarily have to overlap the respective anti-magnetic plates 160 and 170 two-dimensionally. For this reason, it is preferable that the anti-magnetic plates 160 and 170 planarly overlap at least a part of each motor 141 to 145, particularly planarly overlap the stator and rotor.
Also, in the present embodiment, two anti-magnetic plates, the first anti-magnetic plate 160 and the second anti-magnetic plate 170, are provided, but only one of the anti-magnetic plates may be provided. However, sandwiching the motors 141 to 145 between two antimagnetic plates 160 and 170 can improve the antimagnetic performance.

The second magnetic shield plate 170 is arranged between the circuit board 120 and the circuit retainer 122, has a planar shape similar to that of the circuit retainer 122 shown in FIG. It has a shape that does not overlap with 130 . The second magnetic shield plate 170 is screwed to the base plate 100 .

The first anti-magnetic plate 160 is arranged on the dial 11 side of the main plate 100, specifically between the calendar wheel 16 and the main plate 100, as shown in FIG. It is a metal plate provided with a plate-like portion 161 formed in a substantially disk shape covering almost the entire surface of the plate-like portion 161 and an extension portion 162 extending from the outer periphery of the plate-like portion 161 . The first magnetic shield plate 160 is configured to overlap the motors 141 to 145 of the drive mechanism 140 in plan view. The first anti-magnetic plate 160 has a function to prevent the motors 141 to 145 from malfunctioning under the influence of an external magnetic field, and a function to hold down the hour hand, which is the indicator 23, to which the hour hand is attached.
Plate-like portion 161 is screwed to base plate 100 and circuit board 120 at a plurality of locations, and is electrically connected to ground terminal 120B of circuit board 120 . Further, the plate-like portion 161 has a hole in which the pointer shafts 25A, 25B, 25C, the pointer shafts 26, 27, 28, the shaft 29A of the date indicator wheel 29 are arranged, and a hole in which the antenna feed pin 240 is arranged. 165 are formed.
The extending portions 162 extend from a plurality of locations, for example, four locations on the outer periphery of the plate-like portion 161 . A hook portion 163 extending upward is provided at the outer peripheral end portion of the extending portion 162 . A conductive spring portion 164 is formed on the extending portion 162 obliquely upward by cutting and raising.

Here, the fixing structure of the first magnetic shield plate 160, the motors 141 to 145, the circuit board 120, and the circuit holder 122 will be described with reference to FIGS. 5 to 8. FIG. As shown in FIG. 8, a through hole 106 for screw insertion is formed in the base plate 100, and a step portion 106A is formed in the opening of the through hole 106 on the surface side.
A screw pin 180 is arranged in the through hole 106 of the base plate 100 . The screw pin 180 is a pipe member made of metal, and has a flange 181 formed on one end side. The flange 181 is engaged with the stepped portion 106A of the through hole 106 of the base plate 100. As shown in FIG.
Stator 153 , core 151 , substrate seat 155 , and motor substrate 156 are formed with through holes, and screw pins 180 protruding from the back surface of base plate 100 are arranged in these through holes.
A metal screw 191 is screwed into one end of the screw pin 180 from the first magnetic shield 160 side. A metal screw 192 is screwed to the other end of the screw pin 180 . In this embodiment, the screws 192 for fixing the second motor 142, the fourth motor 144, and the fifth motor 145 are, as shown in FIG. The screw pin 180 is screwed through a notch formed in the circuit board 120 . On the other hand, the screw 192 for fixing the first motor 141 and the third motor 143 is screwed onto the screw pin 180 with the head of the screw 192 contacting the circuit board 120 .
As a result, the first antimagnetic plate 160, the base plate 100, the motors 141 to 145, the circuit board 120, and the circuit retainer 122 are sandwiched and fixed by two screws 191 and 192 screwed into the screw pins 180.
The circuit board 120 is formed with a ground terminal 120B with which the fixing piece 124 of the circuit retainer 122 and the screw 192 abut. Therefore, the metal first magnetic shield 160 is electrically connected to the ground terminal 120B of the circuit board 120 via the metal screw 191, screw pin 180, screw 192, and circuit retainer 122. FIG. Ground terminals 120B are formed at a plurality of locations on the back surface of the circuit board 120. Each ground terminal 120B is connected to screw pins 180, screws 191, and screws arranged at a plurality of locations that are also used to fix the motors 141 to 145. 192 electrically connects to the first magnetic shield 160 at a plurality of locations.
As shown in FIG. 8, a calendar presser 18 is arranged between the first anti-magnetic plate 160 and the solar panel 50 to restrict movement of the calendar wheel 16 toward the dial 11 side. The calendar retainer 18 is fixed to the main plate 100 via the first anti-magnetic plate 160 .

The dial ring 40 is made of a ring-shaped synthetic resin material having a flat portion 41 and an inclined portion 42 .
The flat plate portion 41 is provided parallel to the cover glass 33 , and the upper surface of the outer peripheral end is in contact with the lower surface of the inner periphery of the bezel 32 . The inclined portion 42 extends from the flat plate portion 41 and contacts the dial 11 at its inner peripheral end. The surface of the inclined portion 42 , that is, the inner peripheral surface of the dial ring 40 is inclined toward the back surface of the electronic timepiece 10 , that is, downward, from the upper end connected to the flat plate portion 41 to the lower end that contacts the dial 11 . Therefore, the inner peripheral surface of the dial ring 40 becomes smaller in height relative to the dial 11 toward the inner side of the electronic timepiece 10, and the dial 11 can be viewed over a wide range of angles.

A doughnut-shaped storage space is formed by the dial ring 40 and the bezel 32, and the antenna 200 is stored in this storage space.
Since dial ring 40 is made of a non-conductive material such as synthetic resin, it does not interfere with reception of radio waves by antenna 200 . In addition, since the dial ring 40 covers the antenna 200, the antenna 200 is hidden, and the appearance of the electronic timepiece 10 is prevented from being uncomfortable, and the design of the electronic timepiece 10 can be improved.

[Circuit Configuration of Electronic Clock]
FIG. 9 is a block diagram showing the circuit configuration of the electronic timepiece 10. As shown in FIG.
The electronic timepiece 10 has a GPS receiver section 300 , a control display section 400 and a power supply section 500 arranged on the circuit board 120 .

[GPS receiver]
GPS receiver 300 receives and processes satellite signals from GPS satellites via GPS antenna 200 and SAW (Surface Acoustic Wave) filter 230 . The SAW filter 230 is a band-pass filter that allows 1.5 GHz satellite signals to pass through. An LNA (Low Noise Amplifier) that improves reception sensitivity may be separately inserted between the antenna 200 and the SAW filter 230 . Also, a configuration in which the SAW filter 230 is incorporated in the GPS receiving section 300 may be employed.

The GPS receiver 300 processes satellite signals that have passed through the SAW filter 230, and includes an RF (Radio Frequency) unit 310, a baseband unit 320, a temperature-compensated crystal oscillator circuit (TCXO) 330, and a flash unit. A memory 340 is provided.

The RF section 310 includes a PLL (Phase Locked Loop), a VCO (Voltage Controlled Oscillator), an LNA (Low Noise Amplifier), a mixer, an IF (Intermediate Frequency) amplifier, an IF filter, an ADC (A/D converter), etc. This is a common RF unit for GPS reception.

The baseband unit 320 is a general baseband unit for GPS reception that includes a DSP (Digital Signal Processor), CPU (Central Processing Unit), RTC (Real Time Clock), SRAM (Static Random Access Memory), and the like. be. A TCXO 330 and a flash memory 340 are also connected to the baseband unit 320 .

The baseband unit 320 receives the received signal converted into a digital signal from the RF unit 310, performs correlation processing, positioning calculation, etc. to obtain satellite time information and positioning data, and obtains satellite time information and positioning data. is used to correct the acquired satellite time information, that is, the Z count, and UTC, which is the time data, is calculated. Thereby, baseband section 320 outputs the positioning data and the time data to control display section 400 .
A clock on which the local oscillation signal is based is supplied from the TCXO 330 to the RF section 310 via the baseband section 320 .

Flash memory 340 stores a time difference database or the like in which location information specified by latitude and longitude is associated with time difference information of the location. When position information is obtained in the positioning mode, GPS receiving section 300 obtains time difference information, that is, the time difference from UTC, based on the position information (latitude and longitude), and outputs it to control display section 400 .

[Control display]
The control display unit 400 includes a control unit (CPU) 410 , a driving circuit 420 that drives hands and the like, and a crystal oscillator 430 .

The control unit 410 includes an RTC (Real Time Clock) 411, a ROM 412, and a storage unit 413, keeps time, and outputs a control signal to the GPS receiving unit 300 to control its operation.
The RTC 411 keeps internal time using the reference signal output from the crystal oscillator 430 . Various programs executed by the control unit 410 are stored in the ROM 412 . In this embodiment, the internal time kept by the RTC 411 is UTC, which is Coordinated Universal Time. The control unit 410 updates the RTC 411 with the UTC output from the GPS receiving unit 300 when the reception in the timekeeping mode or the positioning mode is successful.
Storage unit 413 stores satellite time information, positioning information, and time difference information output from GPS receiving unit 300 . Therefore, control unit 410 calculates the time at the current location from UTC and time difference information, drives drive mechanism 140 with drive circuit 420, and indicates the calculated time with hands 22, 23, and 81. FIG.

[Power supply part]
The power supply unit 500 supplies power to the GPS reception unit 300 and the control display unit 400, and includes the solar panel 50, the charging control circuit 510, the secondary battery 130, the first voltage conversion unit 520, and the second voltage conversion unit. 530 and a voltage detection circuit 540 .

The charging control circuit 510 controls charging of the secondary battery 130 with power generated by the solar panel 50 .
The secondary battery 130 supplies drive power to the control display unit 400 through the first voltage converter 520 and supplies drive power to the GPS receiver 300 through the second voltage converter 530 .
Voltage detection circuit 540 monitors the output voltage of secondary battery 130 and outputs it to control unit 410 . Therefore, the control unit 410 can grasp the voltage of the secondary battery 130 detected by the voltage detection circuit 540 and control the reception process.

[Antenna configuration]
10 and 11 are schematic perspective views showing the antenna 200. FIG. 10 is a perspective view of the antenna 200 viewed from the front side, and FIG. 11 is a perspective view of the antenna 200 viewed from the back side.
An antenna 200, which is an antenna for receiving GPS satellite signals, has an antenna element 220 formed on an antenna substrate 210, which is an annular dielectric substrate, by plating, silver paste printing, or the like.
As shown in FIG. 4, the antenna substrate 210 of the present embodiment is formed with arcuate recesses to avoid interference with the buttons 17A to 17D and the crown 14. As shown in FIG. In addition, a plurality of concave portions are formed on the inner peripheral surface of the antenna substrate 210 in order to prevent interference with the fixing portions of the solar panel 50 and the dial 11 . When forming the antenna element 220 on the antenna substrate 210 having such a complicated shape, it is most suitable to form it by plating.
10 and 11, the concave portion of the antenna substrate 210 for avoiding the aforementioned interference is omitted. Further, in the first magnetic shield plate 160 shown in FIG. 10, illustration of holes through which the pointer shafts are inserted and holes in which the screws 191 are arranged is omitted.

As the dielectric that forms the antenna base 210, a ceramic dielectric material that can be used at high frequencies, such as titanium oxide, is mixed with a synthetic resin and molded.
PPS (Poly Phenylene Sulfide), LCP (Liquid Crystal Polymer), and polycarbonate are preferable for the base resin material of the dielectric because they are easily subjected to electroless plating, which will be described later. Accordingly, the antenna 200 can be further miniaturized together with the wavelength shortening of the dielectric. For example, when using the antenna base material 210 with a dielectric constant εr, the wavelength shortening rate of the antenna base material 210 is generally (εr) ^−1/2 . Specifically, the dielectric constant εr is about 7 to 15, and the antenna length can be shortened due to the wavelength shortening effect compared to the case where the antenna base material with such a high dielectric constant is not provided. can be reduced to a size that can be stored inside the wristwatch.

The electroless plating forming the antenna element 220 is made of copper, nickel, and gold, and the thickness of the plating is as thin as about ten and several μm. Therefore, in order to reduce the resistance value of the antenna element 220, the width of the antenna element 220 needs to be about 0.5 mm or more.
Here, the antenna base of the antenna 200 of this embodiment includes an upper surface 211, an outer peripheral surface 212, a lower surface 213, and an inner peripheral surface 214. 1 inner peripheral surface 215 and a second inner peripheral surface 216 provided between the first inner peripheral surface 215 and the lower surface 213 . Therefore, the antenna element 220 has a pentagonal cross section.
As shown in FIG. 10, since the width dimension of the upper surface 211 is small, when the antenna element 220 is formed on the upper surface 211 of the antenna substrate 210, the width of the antenna element 220 becomes narrower, the resistance value increases, and the loss increases. will reduce the antenna gain.
Therefore, in this embodiment, the ground element 221 is formed on the surfaces other than the upper surface 211, specifically, the outer peripheral surface 212 and the lower surface 213 of the antenna substrate 210, and the feeding element 225 is formed on the first inner peripheral surface 215. is doing.

The ground element 221 has an annular shape when the antenna 200 is viewed from the surface of the electronic timepiece 10 in a plan view. The angular range of the ground element 221 in the circumferential direction is set to 360 degrees, that is, the range of the entire circumference.
Feeding element 225 is an arcuate element formed on first inner peripheral surface 215 of antenna base 210 . The feeding element 225 includes a feeding terminal 226 extending from the second inner peripheral surface 216 to the lower surface 213 at a portion of the antenna substrate 210 in the circumferential direction.
The power supply terminal 226 is electrically connected to the power supply terminal 120A of the circuit board 120 by an antenna power supply pin 240 provided through the hole 165 of the first magnetic shield 160 and the through hole 105 of the ground plate 100 . Therefore, the feed element 225 is an element called a feed element or an excitation element to which power is fed via the feed terminal 120A, the antenna feed pin 240 and the feed terminal 226. FIG. By appropriately setting the length of the feeding element 225 , it is possible to match the impedance of the GPS receiving section 300 electrically connected to the antenna 200 and the impedance of the antenna 200 .
In this embodiment, the angular range of the feeding element 225 in the circumferential direction is set to about 315 degrees, but it is not limited to this, and may be set in the range of 40 degrees to 330 degrees, for example.
As a result, the feeding element 225, which is the feeding element of the antenna 200, becomes substantially C-shaped in plan view, and the antenna 200 functions as a C-shaped ring antenna for receiving circularly polarized radio waves.

Next, the mounting structure of the antenna 200 will be described with reference to FIGS. 10, 12 and 13. FIG. 12 and 13 are views showing the engagement structure of the antenna 200, FIG. 12 is a view showing the state before the engagement of the antenna 200, and FIG. 13 is a view showing the state after the engagement of the antenna 200. is.
An outer peripheral surface 212 of the antenna 200 is formed with recessed portions 212A at a plurality of locations, specifically at four locations, and eave-shaped projecting portions 217 are formed in the recessed portions 212A. The outer peripheral surface of the protruding portion 217 is an inclined surface 217A that protrudes outward from the lower surface 213 of the antenna 200 toward the upper side.
A hook portion 163 extending upward is provided at the outer peripheral end portion of the extension portion 162 of the first magnetic shield plate 160, and a through hole 163A is formed in the hook portion 163 to engage with the projecting portion 217. there is A conductive spring portion 164 is formed on the extending portion 162 obliquely upward by cutting and raising.

Pedestals 113 on which the antennas 200 are mounted are formed at a plurality of locations on the base plate 100 . After screwing the first anti-magnetic plate 160 to the ground plate 100, the lower surface 213 of the antenna 200 is brought into contact with the upper surface of the pedestal portion 113 as shown in FIG. 12(A).
12(A) shows a cross section of the antenna 200, the hook portion 163 of the first magnetic shield 160, and the base plate 100, and FIG. 12(B) is a view seen from the direction of arrow A shown in FIG. 12(A). . As shown in FIG. 12, when the antenna 200 is placed on the pedestal portion 113, the through hole 163A of the hook portion 163 and the eave-like projecting portion 217 of the antenna 200 are not engaged. Further, the hook portion 163 abuts on the protruding portion 217 and is biased toward the outer peripheral side to bend.

From this state, as shown in FIG. 13A, hook portion 163 is pulled upward, that is, in the direction of arrow B shown in FIG. As a result, as shown in FIG. 13A, the protruding portion 217 protrudes from the through hole 163A of the hook portion 163. Then, as shown in FIG.
The first anti-magnetic plate 160 is fixed to the base plate 100 by screws, and is made of metal having elasticity. , is pressed against the pedestal portion 113 . In this manner, the antenna 200 is reliably positioned and fixed with respect to the ground plane 100 . Also, the conductive spring portion 164 contacts the ground element 221 on the lower surface 213 of the antenna 200 . As a result, the ground element 221 of the antenna 200 is electrically connected to the first magnetic shield 160 via the four conductive spring portions 164 .

The electroless plating forming the ground element 221 is made of copper, nickel, gold, or the like, and the total thickness of the plating is as thin as about ten and several μm. Therefore, if the hook portion 163 is brought into pressure contact with the concave portion 212A of the outer peripheral surface 212 of the antenna 200 to establish electrical continuity, the electrode due to the plating may be scraped off when the hook portion 163 is engaged, resulting in instability. On the other hand, since the width dimension and the cut-and-bend angle of the conductive spring portion 164 can be adjusted, the biasing force to the lower surface 213 of the antenna 200 can also be set, so that the electrode can be prevented from being scraped off. The electrical connection with the anti-magnetic plate 160 can be ensured. However, if the thickness of the plating of the ground element 221 is sufficient and durability can be ensured, the hook portion 163 may be brought into pressure contact with the concave portion 212A of the outer peripheral surface 212 to ensure conduction.

When the antenna 200 is fixed to the ground plane 100 by the first magnetic shielding plate 160, the ground element 221 is connected to the first magnetic shielding plate 160, which serves as a ground plane, through the conductive spring portions 164 provided at four locations on the first magnetic shielding plate 160. electrically connected. In this way, by electrically connecting the ground element 221 and the first magnetic shield plate 160, which serves as the ground plane, at a plurality of locations, the potential difference between the ground element 221 and the ground plane is reduced, and the ground plane is effective. becomes larger.
Also, the first magnetic shield 160 is sized to overlap the antenna 200 in plan view. Therefore, by using the first magnetic shield plate 160 as a ground plane and electrically connecting it to the ground element 221 provided in the antenna 200, the area of the ground plane can be increased, the impedance of the ground plane can be lowered, and the antenna performance can be improved. can improve.
In addition, if the feeding element 225 is arranged on the center side with respect to the ground plane, the effect of the ground plane can be maximized, and the axial ratio is improved for reception of circularly polarized radio waves. Arranging the feeding element 225, which is a feeding element, on the surface 215 is preferable in that the reception performance can be improved.
Ground element 221 of antenna 200 is electrically connected to ground terminal 120B of circuit board 120 at a plurality of locations via screw pin 180, screws 191 and 192, and circuit retainer 122, as described above. Although the ground element 221 is electrically connected to the ground terminal 120B of the circuit board 120 via the first magnetic shield 160, it is directly electrically connected to the ground terminal 120B of the circuit board 120 without the first magnetic shield 160. Conductive pins may be provided.
Also, the ground terminal 120B of the circuit board 120 is electrically connected to the back cover 34 via the electrical connection spring portion 123 of the circuit retainer 122 . Therefore, the metal back cover 34 and the metal exterior case 30 to which the back cover 34 is attached are connected to the ground potential. Therefore, in this embodiment, in addition to the first anti-magnetic plate 160, the exterior case 30 and back cover 34 can also be used as a ground plane, and the area of the ground plane can be maximized to improve the antenna performance.

After attaching the antenna 200 , the solar panel 50 and the dial 11 are attached to the inner peripheral side of the antenna 200 . As for the mounting structure of the solar panel 50 and the dial plate 11, the same structure as the conventional one can be adopted. For example, a plurality of recesses are formed on the inner peripheral surface 214 of the antenna 200, fixing projections formed on the main plate 100 are arranged in these recesses, and grooves formed on the outer peripheral edges of the solar panel 50 and the dial plate 11 are engaged. The solar panel 50 and the dial plate 11 can be fixed to the main plate 100 by joining them together. Further, the dial ring 40 may be fixed to the main plate 100 by fitting a fixing pin or the like formed in the main plate 100 into a hole (not shown) formed in the dial ring 40 .

As described above, the antenna 200 is arranged around the outer periphery of the dial 11, that is, around the time display portion, is arranged inside the bezel 32, and is further covered with the dial ring 40 and the cover glass 33 made of synthetic resin. , it is possible to ensure good reception.
The antenna 200 is fed with power through a feed terminal 226 provided on the bottom surface of the antenna 200, and an antenna feed pin 240 is connected to the feed terminal 226 as shown in FIG. Antenna feed pin 240 is a pin-shaped connector made of metal, is disposed through first magnetic shield plate 160 and ground plate 100 , and abuts feed terminal 120 A of circuit board 120 . Thereby, the circuit board 120 and the antenna 200 are electrically connected via the antenna feeding pin 240 .

[Antenna characteristics]
Next, the characteristics of the antenna 200 of this embodiment will be described.
FIG. 14 is a characteristic diagram showing the radiation pattern of the antenna 200. As shown in FIG. In FIG. 14, a solid line 901 is the right-handed polarization characteristic of the antenna, and a dotted line 902 is the left-handed polarization characteristic of the antenna. In FIG. 14, 0 degrees is the direction of the dial surface, 180 degrees is the direction of the back cover, and 90 degrees and 270 degrees are the side directions of the electronic timepiece 10 . Therefore, in the right-handed polarized wave characteristic, directivity in the dial-back cover direction, that is, in the thickness direction of the electronic timepiece 10 is obtained. For example, the antenna 200 has a gain of −5.3 dBic in the front direction of the dial, and is an antenna suitable for receiving satellite signals that are right-hand circularly polarized waves.

[Action and effect of the embodiment]
According to this embodiment, since the ground element 221 is provided on the outer peripheral surface 212 and the lower surface 213 of the antenna substrate 210 of the antenna 200, and the feed element 225 is provided on the inner peripheral surface 214, the feed element 225 and the ground element 221 distance variation can be eliminated. Therefore, reception performance can be stabilized.
Further, by bringing the conductive spring portion 164 of the metal first magnetic shield plate 160 into contact with the ground element 221, the first magnetic shield plate 160 is used as a ground plane, so that the antenna characteristics can be further improved. Furthermore, the first magnetic shield plate 160 is provided with a function to prevent the motors 141 to 145 from malfunctioning under the influence of an external magnetic field, and a function to hold down the hour wheel to which the hour hand, which is the pointer 23, is attached. Since this existing part is used as a ground plane, there is no need to use a new part for the ground plane, and an increase in the number of parts can be suppressed.
Furthermore, in an unbalanced feeding antenna that requires a ground plane, the first magnetic shield plate 160, which is an existing timepiece component, can be used to form a large ground plane, so that the size of the timepiece can be reduced while the antenna performance can be improved.
Since the ground terminal 120B of the circuit board 120 and the first magnetic shield plate 160 are electrically connected by screw pins 180 and screws 191 and 192 provided at a plurality of locations, the ground element 221 of the antenna 200 is connected to the first magnetic shield plate. 160 to the ground terminal 120B of the circuit board 120, and the effect of the ground plane can be improved. Furthermore, since the ground element 221 of the antenna 200 and the ground terminal 120B of the circuit board 120 are arranged with the ground plane 100 and the drive mechanism 140 interposed therebetween, it is structurally difficult to directly connect them, but the first magnetic shield 160 Like the circuit board 120, it has a large planar size, so it is possible to avoid interference with the wheel train, the motors 141 to 145, etc., and easily establish electrical connection. It is also possible to reduce the size of the movement.
Moreover, in the above embodiment, the screw pin 180 and the screws 191 and 192 that conduct the first magnetic shield 160 and the ground terminal 120B of the circuit board 120 are connected to the base plate 100, the first magnetic shield 160, the motors 141 to 145, the circuits Since it is also used for fixing the substrate 120, the circuit holder 122, etc., the number of parts can be reduced compared to the case of separately providing a pin for conduction between the first magnetic shield plate 160 and the circuit substrate 120, and the movement is also reduced. Can be made smaller.

Since the first magnetic shielding plate 160 overlaps the antenna 200 in a plan view, it can be configured with a diameter size approximately equal to that of the antenna 200 . Therefore, the size of the first magnetic shield plate 160 used as the ground plane can be increased, and the antenna performance can be improved.
In addition, since the ground element 221 of the antenna 200 and the first magnetic shield plate 160 are electrically connected at a plurality of locations, the potential difference between the ground element 221 and the first magnetic shield plate 160 can be reduced compared to the case where there is continuity at one location. can improve the effect as a ground plane.

In the antenna 200, the feeding element 225 is formed on the first inner peripheral surface 215 and arranged closer to the center of the ground plane than the ground element 221, so that the effect of the ground plane can be improved.
Since the ground element 221 is formed on the lower surface 213 of the antenna substrate 210 , it can be easily connected to the first magnetic shield 160 . Further, since the ground element 221 is also formed on the outer peripheral surface 212 of the antenna substrate 210, the area of the ground element 221 can be secured. Therefore, by reducing the width of the antenna 200, the parting diameter of the dial 11 arranged on the inner peripheral side of the ring-shaped antenna 200 can be increased, and the antenna performance can be improved.
In addition to the first antimagnetic plate 160, the external case 30 and back cover 34 of the electronic timepiece 10 can function as a ground plane, so the size of the ground plane can be maximized and the antenna performance can be improved.

A projecting portion 217 is formed on the antenna 200 , a hook portion 163 is formed on the first magnetic shield plate 160 , and the projecting portion 217 and the hook portion 163 are engaged with each other, whereby the antenna 200 is attached to the ground plane via the first magnetic shield plate 160 . 100 can be installed. Therefore, compared to the case where the antenna 200 is screwed, it can be assembled more easily, the assembling workability of the electronic timepiece 10 can be improved, and the manufacturing cost can be reduced.
Since the antenna 200 is covered with the dial ring 40 made of synthetic resin, the design can be improved without impairing the performance of the antenna. Moreover, since the bezel 32 made of metal is used, the appearance of the electronic timepiece 10 can be improved, and the sense of quality can be enhanced.

[Second embodiment]
An electronic timepiece 10A of a second embodiment will be described with reference to FIGS. 15 and 16. FIG. FIG. 15 is a plan view showing the electronic timepiece 10A, and FIG. 16 is a schematic cross-sectional view of the electronic timepiece 10A.
The electronic timepiece 10A is a digital timepiece whose time display section is composed of a liquid crystal panel 630. FIG. That is, the electronic timepiece 10A includes a metal exterior case 601, a cover glass 602, and a metal back cover 603. As shown in FIG. Two buttons 604 are provided on the side surface of the exterior case 601 and three button switches 605 are provided on the surface of the exterior case 601 . A shaft portion 605A of the button switch 605 penetrates the outer case 601 and protrudes into the outer case 601 .

A base plate 610 is arranged inside the exterior case 601 , and a circuit board 620 is arranged on the surface of the base plate 610 . A control IC 621 for controlling the operation of the electronic timepiece 10A and a tact switch 622 are mounted on the surface of the circuit board 620 on the cover glass 602 side. A liquid crystal panel 630 and an antenna 640 are arranged on the surface side of the circuit board 620 .
The liquid crystal panel 630 is formed in a planar rectangular shape and held by a panel frame 631 made of plastic.
The antenna 640 is a planar rectangular frame-shaped ring antenna arranged along the outer circumference of the panel frame 631 . That is, they are arranged on the periphery of the liquid crystal panel 630 . A feeding element is provided on the inner peripheral surface of the antenna 640, and ground elements are provided on the outer peripheral surface and the lower surface. The feeder element and the ground element have the same configuration as in the first embodiment, and the description thereof is omitted.
Blindfold printing 602 A is provided on the periphery of the lower surface of the cover glass 602 to prevent the panel frame 631 and the antenna 640 from being seen through the cover glass 602 .

The tact switch 622 is a switch that is input by contacting the shaft portion 605A when the button switch 605 is pressed. A shield plate 623 is arranged on the surface side of the tact switch 622 . The shield plate 623 is a planar rectangular stainless steel plate, and has three holes through which the shaft portion 605A is inserted. Shield plate 623 extends to the bottom surface of antenna 640 and contacts the ground element on the bottom surface of antenna 640 . Thereby, the shield plate 623 functions as a ground plate.

An RF-IC 641 that performs reception processing by an antenna 640 , a battery 650 that serves as a power source, a circuit holding plate 660 , and a piezoelectric element 670 are provided on the rear surface of the circuit board 620 on the rear cover 603 side. The circuit pressing plate 660 is provided with a conduction spring portion 661 that is electrically connected to the back cover 603 . Further, the circuit board 620 is provided with a power supply terminal electrically connected to the power supply element of the antenna 640 , and is also provided with one or more ground terminals electrically connected to the shield plate 623 .

In the second embodiment, since the shield plate 623 extends to the bottom surface of the antenna 640 and contacts the ground element, the shield plate 623 can be used as a ground plane, improving the antenna performance.

[Modification]
It should be noted that the present disclosure is not limited to the above-described embodiments, and includes modifications, improvements, and the like within a range that can achieve the purpose of the present disclosure.
In the above embodiment, the first magnetic shield plate 160 is formed with the hook portion 163 that engages with the protruding portion 217 of the antenna 200, but as shown in FIG. . The hook portion 101 of the base plate 100 engages with the projecting portion 217 provided on the outer circumference of the antenna 200 , thereby fixing the antenna 200 to the base plate 100 . In this case, since there is no need to form the hook portion 163 on the first magnetic shielding plate 160, the shape of the first magnetic shielding plate 160 can be simplified, and the bending process can be reduced, thereby reducing the cost.

In the above embodiment, the first magnetic shield plate 160 is used as a ground plane. However, as in an electronic timepiece 10B shown in FIG. The panel support substrate 51 may be extended to the bottom surface of the antenna 200 and electrically connected to the ground element 221 of the antenna 200, and the solar panel support substrate 51 may be used as a ground plane.

In the above-described embodiment, two anti-magnetic plates, the first anti-magnetic plate 160 and the second anti-magnetic plate 170, are used. good. For example, if the back cover 34 is provided with magnetic resistance, the back cover 34 also functions as a magnetic shield, so the second magnetic shield 170 on the back cover side of the drive mechanism 140 can be omitted.
The exterior case 30 and back cover 34 may be electrically connected to the ground element 221 of the antenna 200 via the first magnetic shield plate 160 and the second magnetic shield plate 170, or directly connected to the ground terminal 120B of the circuit board 120. You may

The first magnetic shield 160 that functions as a ground plane is not limited to one that overlaps the antenna 200 in plan view. For example, a magnetic shield that is arranged inside the inner circumference of the antenna 200 and does not overlap the antenna 200 in a plan view may be used.
Although the ground element 221 of the antenna 200 and the first magnetic shield 160 are electrically connected by the conduction spring portions 164 at four locations, the number of electrically connected locations may be five or more, or three or less. .
Further, although the conductive spring portion 164 is formed in the first magnetic shield plate 160 and is electrically connected to the ground element 221, a conductive member that is a separate part from the magnetic shield plate may be provided to electrically connect the magnetic shield plate and the ground element 221. good.

In the above embodiment, the ground element 221 is formed on both the outer peripheral surface 212 and the lower surface 213 of the antenna substrate 210 , but the ground element 221 may be formed only on either the outer peripheral surface 212 or the lower surface 213 .
In each of the above-described embodiments, the external cases 30, 601 and back covers 34, 603 made of conductive material are electrically connected to the ground terminals 120B of the circuit boards 120, 620 to function as ground planes. Only the case 30, 601 or only the back cover 34, 603 may function as the ground plane. Furthermore, only the first magnetic shield plate 160 may function as a ground plane.

Antenna 200 may be fixed to base plate 100 by screwing instead of being fixed by engagement of projecting portion 217 and hook portions 163 and 101 . Antenna 200 is not limited to one that receives GPS satellite signals, Bluetooth (registered trademark), BLE (Bluetooth Low Energy), Wi-Fi (registered trademark), NFC (Near Field Communication), LPWA (Low Power Wide Area ) for transmitting and receiving other radio waves.

[Summary of this disclosure]
An electronic timepiece according to the present disclosure includes a time display unit including hands and a dial, an antenna disposed around the time display unit and having a feed element and a ground element formed on an annular dielectric base material, and the hands. a main plate to which a driving motor is attached; a magnetic shield plate that overlaps the motor in a plan view seen in a direction perpendicular to the surface of the dial and is electrically connected to the ground element; A circuit board having a power supply terminal and a ground terminal electrically connected to the ground element through the antimagnetic plate is provided.
According to the electronic timepiece of the present disclosure, since the feeding element and the grounding element are provided on the dielectric base material of the antenna, it is possible to reduce distance fluctuations between the feeding element and the grounding element, thereby stabilizing reception performance.
Moreover, since the antimagnetic plate is electrically connected to the ground element, the antimagnetic plate can be used as a ground plane, and the antenna characteristics can be further improved. Furthermore, the anti-magnetic plate is an existing part that prevents the motor from malfunctioning due to the influence of an external magnetic field. An increase in the number of parts can be suppressed.
In addition, since the unbalanced feed antenna requires a ground plane, the anti-magnetic plate, which is an existing watch component, is used to construct a large ground plane, so it is possible to achieve both a smaller watch and improved antenna performance.

In the electronic timepiece of the present disclosure, it is preferable that the antenna and the magnetic shield plate overlap each other in the plan view.
The anti-magnetic plate, which overlaps the ring-shaped antenna in which the feeding element and the grounding element are formed on the ring-shaped dielectric base material in a plan view, is a large component having a diameter approximately equal to that of the antenna. By using this antimagnetic plate as a ground plane, the size of the ground plane can be increased and the antenna performance can be improved.

In the electronic timepiece of the present disclosure, it is preferable that the ground element and the antimagnetic plate are electrically connected at a plurality of locations.
According to the electronic timepiece of the present disclosure, since the ground element and the antimagnetic plate are electrically connected at a plurality of locations, the potential difference between the ground element and the antimagnetic plate can be reduced compared to the case where the electrical connection is at one location, and the ground plane It can improve the effect as

In the electronic timepiece of the present disclosure, it is preferable that the feed element is formed on the inner peripheral surface of the dielectric substrate, and the ground element is formed on at least one of the lower surface and the outer peripheral surface of the dielectric substrate. .
According to the electronic timepiece of the present disclosure, it is possible to arrange the feeder element closer to the central portion of the plane of the ground plane than the ground element, so that the effect of the ground plane can be improved.
If the ground element is formed on the lower surface of the dielectric base material, it is easy to ensure electrical connection with the antimagnetic plate. If the ground element is formed on the outer peripheral surface of the dielectric base material, the area of the ground element can be secured even if the width dimension of the dielectric base material, that is, the width dimension of the lower surface is reduced. Therefore, by reducing the width of the antenna, the parting diameter of the dial arranged on the inner peripheral side of the ring-shaped antenna can be increased, and the antenna performance can be improved.
Furthermore, if the ground element is formed across the outer peripheral surface and the lower surface of the dielectric substrate, the area of the ground element can be increased and the antenna performance can be improved.

The electronic timepiece of the present disclosure includes an exterior case and a back cover made of a conductive material, the exterior case and the back cover being electrically connected to the ground terminal and serving as a ground plane for the antenna together with the magnetic shield. It is preferred that it works.
According to the electronic timepiece of the present disclosure, the external case and back cover of the electronic timepiece can function as a ground plane in addition to the antimagnetic plate, so the size of the ground plane can be maximized and the antenna performance can be improved.

In the electronic timepiece of the present disclosure, it is preferable that the antenna is formed with a projecting portion, and the anti-magnetic plate or the main plate has a hook portion that engages with the projecting portion.
According to the electronic timepiece of the present disclosure, it can be assembled by engaging the protruding portion of the antenna with the hook portion of the antimagnetic plate or the main plate, and can be assembled more easily than when the antenna is screwed. Therefore, the workability of assembling the electronic timepiece can be improved, and the manufacturing cost can be reduced.

In the electronic timepiece of the present disclosure, it is preferable that the circuit board and the antimagnetic plate are screwed at a plurality of locations and electrically connected.
According to the electronic timepiece of the present disclosure, by screwing the circuit board and the antimagnetic plate together at a plurality of locations, the ground pattern of the circuit board and the antimagnetic plate can be reliably connected, and the effect of the ground plane can be improved.

An electronic timepiece according to the present disclosure includes a time display portion that displays time, an antenna disposed around the time display portion and having a feed element and a ground element formed on an annular dielectric base material, and an electric power supply to the ground element. a metal plate that is physically connected to function as a ground plane and has a function other than the ground plane; a feed terminal connected to the feed element; and a feed terminal connected to the ground element through the metal plate. and a circuit board having a ground terminal.
In the electronic timepiece of the present disclosure, the time display unit is not limited to the hands-type time display unit, and may be a digital time display unit. As the metal plate, those having functions such as a solar support substrate for supporting a solar panel and a shield plate for static electricity countermeasures can be used.
According to the electronic timepiece of the present disclosure, since the feeding element and the grounding element are provided on the dielectric base material of the antenna, it is possible to reduce distance fluctuations between the feeding element and the grounding element, thereby stabilizing reception performance.
Moreover, since the metal plate is electrically connected to the ground element, the metal plate can be used as a ground plane, and the antenna characteristics can be further improved. Furthermore, since the metal plate is an existing part such as a solar indicator board or a shield plate, and since this existing part is used as a ground plane, there is no need to use a new part for the ground plane, and an increase in the number of parts can be suppressed. .
In addition, since the unbalanced feed antenna requires a ground plane, the anti-magnetic plate, which is an existing watch component, is used to construct a large ground plane, so it is possible to achieve both a smaller watch and improved antenna performance.

10... Electronic watch 10A... Electronic watch 10B... Electronic watch 11... Dial plate 14... Crown 15... Small calendar window 16... Calendar wheel 17A... A button 17B... B button 17C... C button, 17D... D button, 18... Calendar holder, 21... Pointer, 22... Pointer, 23... Pointer, 25... Pointer shaft, 25A... Pointer shaft, 25B... Pointer shaft, 25C... Pointer shaft, 26... Pointer shaft, 27... Pointer Axis 28... Pointer axis 29... Date wheel 29A... Shaft 30... Exterior case 32... Bezel 33... Cover glass 34... Back cover 40... Dial ring 41... Flat plate part 42... Inclined part , 50... Solar panel, 51... Solar panel support substrate, 70... First small window, 71... Pointer, 80... Second small window, 81... Pointer, 90... Third small window, 91... Pointer, 100... Main plate, DESCRIPTION OF SYMBOLS 101... Hook part 105... Through-hole 106... Through-hole 106A... Step part 113... Base part 120... Circuit board 120A... Feeding terminal 120B... Ground terminal 122... Circuit holder 123... Conduction spring part , 124... Fixed piece, 130... Secondary battery, 140... Drive mechanism, 141... First motor, 142... Second motor, 143... Third motor, 144... Fourth motor, 145... Fifth motor, 151... Core , 152... Coil, 153... Stator, 154... Rotor, 155... Substrate seat, 156... Motor substrate, 160... First anti-magnetic plate, 161... Plate-like part, 162... Extension part, 163... Hook part, 163A... Penetration Hole 164 Conductive spring portion 165 Hole 170 Second magnetic shield plate 180 Screw pin 181 Flange 191 Screw 192 Screw 200 Antenna 210 Antenna base 211 Upper surface 212 Outer peripheral surface 212A Concave portion 213 Lower surface 214 Inner peripheral surface 215 First inner peripheral surface 216 Second inner peripheral surface 217 Protruding portion 217A Inclined surface 220 Antenna element 221 Ground element 225 Feeding element 226 Feeding terminal 230 SAW filter 240 Antenna feeding pin 300 GPS receiver 310 RF section 320 Baseband section 340 Flash memory 400 Control Display unit 410 Control unit 411 RTC 412 ROM 413 Storage unit 420 Drive circuit 430 Crystal oscillator 500 Power supply unit 510 Charging control circuit 520 First voltage conversion unit , 530... Second voltage converter, 540... Voltage detection circuit, 601... Exterior case, 602... Cover glass, 60 2A Blindfold printing 603 Back cover 604 Button 605 Button switch 605A Shaft 610 Base plate 620 Circuit board 621 Control IC 622 Tact switch 623 Shield plate 630 Liquid crystal panel 631 Panel frame 640 Antenna 641 RF-IC 650 Battery 660 Circuit pressing plate 661 Conductive spring portion 670 Piezoelectric element 901 Solid line 902 Dotted line.

Claims (8)

a time display unit comprising hands and a dial;
an antenna disposed around the time display portion and having a feed element and a ground element formed on an annular dielectric base;
a base plate to which a motor for driving the hands is attached;
a magnetic shield that overlaps the motor in plan view in a direction perpendicular to the surface of the dial and is electrically connected to the ground element;
An electronic timepiece comprising: a circuit board having a power supply terminal connected to the power supply element, and a ground terminal electrically connected to the ground element through the antimagnetic plate. The electronic timepiece according to claim 1,
The electronic timepiece according to claim 1, wherein the antenna and the antimagnetic plate overlap each other in plan view. In the electronic timepiece according to claim 1 or claim 2,
An electronic timepiece, wherein the ground element and the antimagnetic plate are electrically connected at a plurality of points. In the electronic timepiece according to any one of claims 1 to 3,
The feed element is formed on the inner peripheral surface of the dielectric base material,
An electronic timepiece, wherein the ground element is formed on at least one of a lower surface and an outer peripheral surface of the dielectric base material. In the electronic timepiece according to any one of claims 1 to 4,
Equipped with an exterior case and back cover made of conductive material,
An electronic timepiece according to claim 1, wherein the external case and back cover are electrically connected to the ground terminal and function together with the antimagnetic plate as a ground plane for the antenna. In the electronic timepiece according to any one of claims 1 to 5,
a protrusion is formed on the antenna;
The electronic timepiece, wherein the antimagnetic plate or the main plate includes a hook portion that engages with the projecting portion. In the electronic timepiece according to any one of claims 1 to 6,
An electronic timepiece, wherein the circuit board and the anti-magnetic plate are screwed at a plurality of locations and electrically connected. a time display unit that displays the time;
an antenna disposed around the time display portion and having a feed element and a ground element formed on an annular dielectric base;
a metal plate that is electrically connected to the ground element, functions as a ground plane, and has a function other than the ground plane;
An electronic timepiece, comprising: a circuit board having a power supply terminal connected to the power supply element, and a ground terminal connected to the ground element via the metal plate.

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