Electronic clock

Abstract

We provide an electronic clock that can be made thinner while maintaining antenna performance. [Solution] The electronic clock 1 comprises a pointer shaft 4 to which a pointer 3 is attached, an antenna 50 having a planar first conductor element 52 connected to a power supply unit 56, a planar second conductor element 53 that overlaps with the first conductor element 52 in a planar view, a dielectric 51 disposed between the first conductor element 52 and the second conductor element 53, and a short-circuit portion 54 that short-circuits the first conductor element 52 and the second conductor element 53, and a case 10 that houses the antenna 50, wherein the first conductor element 52 has an open end 57 located on the opposite side of the pointer shaft 4 from the short-circuit portion 54, and the first distance L1 between the first conductor element 52 and the second conductor element 53 in the region where the short-circuit portion 54 is located is smaller than the second distance L2 between the first conductor element 52 and the second conductor element 53 in the region where the open end 57 is located.

Description

Technical Field

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

Background Art

[0002] In small electronic clocks such as wristwatches, an electronic clock incorporating an antenna for receiving satellite signals transmitted from GPS satellites is known. For example, in Patent Document 1, a first conductor element connected to a power supply unit, a second conductor element overlapping the first conductor element in plan view, a dielectric disposed between the first conductor element and the second conductor element, and a short-circuit unit for short-circuiting the first conductor element and the second conductor element, an antenna having the same, and a case for housing the antenna are provided, and the distance between the antenna open end disposed on the side opposite to the short-circuit unit and the case is relatively increased to make the directivity of the antenna vertically upward to improve the antenna performance. An electronic clock is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the electronic clock described in Patent Document 1, when trying to reduce the thickness of the antenna in order to make the clock thinner, the antenna performance deteriorates, so it has been difficult to make the electronic clock incorporating the antenna thinner.

Means for Solving the Problems

[0005] The electronic clock comprises a pointer shaft to which a pointer is attached, a planar first conductor element connected to a power supply unit, a planar second conductor element that overlaps with the first conductor element in a plan view, a dielectric disposed between the first conductor element and the second conductor element, an antenna having a short-circuit portion that short-circuits the first conductor element and the second conductor element, and a case for housing the antenna, wherein the first conductor element has an open end located on the opposite side of the pointer shaft from the short-circuit portion, and the first distance between the first conductor element and the second conductor element in the region where the short-circuit portion is located is smaller than the second distance between the first conductor element and the second conductor element in the region where the open end is located. [Brief explanation of the drawing]

[0006] [Figure 1] An explanatory diagram showing an electronic clock and a position information satellite according to the first embodiment. [Figure 2] A cross-sectional view showing the schematic structure of an electronic clock according to the first embodiment. [Figure 3] An exploded perspective view showing the configuration of the movement 20 of the electronic clock of this embodiment. [Figure 4] A plan view showing the components arranged on the base plate of the electronic clock of this embodiment. [Figure 5] A schematic cross-sectional view of the antenna of the electronic clock according to this embodiment. [Figure 6] A perspective view showing the main part of the antenna of the electronic clock of this embodiment. [Figure 7] A perspective view showing the main part of the antenna of the electronic clock of this embodiment. [Figure 8] A perspective view showing the main part of the antenna of the electronic clock of this embodiment. [Figure 9] A diagram showing the relationship between antenna thickness and antenna gain. [Figure 10] A diagram showing the relationship between antenna thickness and antenna gain. [Figure 11] This figure shows the simulation results of the current direction of the antenna in this embodiment. [Figure 12] This figure shows the simulation results of the electric field distribution of the antenna in this embodiment. [Figure 13] A perspective view showing the main part of the antenna of an electronic clock according to the second embodiment. [Figure 14] This diagram shows the relationship between antenna thickness and antenna gain with and without the presence or absence of an antenna support member. [Figure 15] A perspective view showing the main part of the antenna of an electronic clock according to the third embodiment. [Figure 16] A perspective view showing the main part of the antenna of an electronic clock according to the fourth embodiment. [Modes for carrying out the invention]

[0007] 1. First Embodiment First, the electronic clock 1 according to the first embodiment will be described with reference to Figures 1 to 12. In this embodiment, the side with the cover glass 15 of the electronic clock 1 is described as the front side or upper side, and the side with the back cover 14 is described as the back side or lower side. Furthermore, a plan view means viewing the electronic clock 1 from a direction perpendicular to the surface of the dial 2, that is, from the axis of the pointer axis 4, and a side view means viewing the electronic clock 1 from a direction parallel to the surface of the dial 2.

[0008] The electronic clock 1 of this embodiment incorporates an antenna 50, which will be described later, and is configured to receive satellite signals from multiple GPS satellites and quasi-zenith satellites orbiting the Earth in predetermined orbits, acquire satellite time information, and correct its internal time information.

[0009] As shown in Figures 1 and 2, the electronic clock 1 comprises a case 10 and a dial 2, hands 3, and a date wheel 5 housed within the case 10. The electronic clock 1 also includes a crown 6 for external operation and two buttons 7 and 8.

[0010] [Exterior structure of an electronic clock] The case 10 includes a case body 11 and a back cover 14. The case body 11 includes a cylindrical body 12 and a ring-shaped bezel 13 provided on the surface side of the body 12. In the present embodiment, the body 12 and the back cover 14 are separately configured, but it is not limited thereto, and a one-piece case in which the body 12 and the back cover 14 are integrated may also be used. Further, in the present embodiment, the body 12 and the bezel 13 are separately configured, but it is not limited thereto, and a structure in which the body 12 and the bezel 13 are integrated may also be used, and in this case, there is an advantage that it can be made inexpensive. The materials of the body 12, the bezel 13, and the back cover 14 are metal materials such as stainless steel, titanium alloy, aluminum, and brass, that is, conductive materials.

[0011] A cover glass 15 is attached to the bezel 13 via a plastic packing 17. The cover glass 15 is made of a transparent material such as mineral glass, sapphire glass, or organic glass. The glass diameter, which is the diameter of the cover glass 15, is determined by the size of the case 10, and the thickness dimension of the cover glass 15 is determined by the relationship between the glass diameter and the waterproof performance.

[0012] [Internal Structure of the Electronic Watch] Next, the internal structure incorporated in the case 10 of the electronic watch 1 will be described. As shown in FIG. 2, a dial 2, a dial ring 16, a movement 20, an antenna 50, etc. are accommodated in the case 10.

[0013] The dial 2 is formed in a disc shape from a non-conductive member. The dial 2 of the present embodiment is formed from a polycarbonate resin having a dielectric constant of 3. The dial 2 is formed in a size corresponding to the case 10. That is, the planar size of the dial 2, that is, the diameter of the dial 2 in plan view, is set according to the inner diameter of the case 10. As shown in Figure 2, the pointer 3 comprises an hour hand 31, a minute hand 32, and a second hand 33. A through hole 2A is formed in the center of the plane of the dial 2, and three pointer shafts 4 are arranged coaxially in the through hole 2A. The hour hand 31 is attached to pointer shaft 35, the minute hand 32 is attached to pointer shaft 36, and the second hand 33 is attached to pointer shaft 37. The hour hand 31, minute hand 32, and second hand 33 are set to lengths corresponding to the plane size of the dial 2. The pointer shafts 35, 36, and 37, and the hour hand 31, minute hand 32, and second hand 33 are made of conductive metal components. A rectangular date window 2B is provided at the 3 o'clock position on the dial 2. The date wheel 5, which is the display wheel, is located on the reverse side of the dial 2, and the date wheel 5 is visible through the date window 2B. The hour hand 31, minute hand 32, second hand 33, and date wheel 5 are driven via a stepper motor and gear train, which will be described later. Note that the display wheel is not limited to the date wheel 5; it may also display calendar information such as the day of the week wheel, or information other than the calendar.

[0014] The dial ring 16, like the dial 2, is made of a non-conductive material and is configured in a ring shape in plan view, and is positioned along the outer circumference of the dial 2. In this embodiment, the dial ring 16 is made of polycarbonate resin with a dielectric constant of 3.

[0015] The movement 20 includes a base plate 21, a drive mechanism 23, a battery 24, a solar panel 25, an antenna 50, a circuit board 70, a magnetic shielding plate 81, a circuit retainer 82, and the like. Although not shown in the illustration, a gear train support is positioned between the base plate 21 and the circuit board 70 to support the gear train constituting the drive mechanism 23 together with the base plate 21.

[0016] The base plate 21 is made of synthetic resin, and its planar size is constant regardless of the inner diameter of the case 10. That is, the drive mechanism 23 is attached to the back surface of the base plate 21. For this reason, the base plate 21 is formed to a size that corresponds to the drive mechanism 23, that is, a size on which the drive mechanism 23 can be attached. Therefore, even if the inner diameter of the case 10 increases, the planar size of the base plate 21 can be kept constant. In the electronic clock 1, the outer diameter of the base plate 21 is small compared to the inner diameter of the case 10. The drive mechanism 23 is mounted on the back surface of the base plate 21 and drives the hour hand 31, minute hand 32, second hand 33, and date wheel 5. Specifically, the drive mechanism 23 has four stepper motors that drive the hour hand 31, minute hand 32, second hand 33, and date wheel 5 respectively, and four gear trains. These stepper motors are positioned so as not to overlap with the battery 24 in a plan view. Figure 2 shows the stepper motor 233 that drives the second hand 33.

[0017] The circuit board 70 has semiconductor integrated circuits (ICs), resistors, capacitors, and other circuit elements mounted on both its front and back surfaces. The ICs include a receiving IC for processing signals received by the antenna 50, and control ICs for controlling the driving of the hour hand 31, minute hand 32, second hand 33, and sun wheel 5. The circuit board 70 is positioned on the back side of the gear train bearing and is sized to correspond to the base plate 21, that is, to correspond to the drive mechanism 23. Battery 24 is a button-type lithium-ion battery and is located in the notch of the circuit board 70.

[0018] The solar panel 25 is a solar cell panel used for a wristwatch, and can utilize, for example, a film-type solar cell in which an amorphous silicon thin film is laminated on a resin film substrate. The solar panel 25 has through holes 25A through which the pointer shafts 35-37 are inserted. The current generated by the solar panel 25 is used to charge the battery 24 via the circuit board 70. Therefore, the battery 24 is a secondary battery that charges the current generated by the solar panel 25.

[0019] The configuration of movement 20 will be explained with reference to Figure 3. As shown in Figure 3, the movement 20 is constructed by stacking the solar panel 25, antenna 50, base plate 21, circuit board 70, magnetic shielding plate 81, and circuit retainer 82 in that order. Note that the magnetic shielding plate 81 and the circuit retainer 82 are an integrated circuit board.

[0020] The antenna 50, as will be described in detail below, is composed of a dielectric 51, a first conductor element 52 placed on the dielectric 51, and a second conductor element 53 placed below the dielectric 51. The second conductor element 53 is provided with a bent portion 58 that protrudes downward. A solar panel 5 is positioned between the dielectric 51 and the second conductor element 53. The first conductor element 52 is electrically connected to the circuit board 70 by a pin-shaped power supply section 56.

[0021] Next, the positional relationships of each component placed on the base plate 21 will be explained with reference to Figure 4. As shown in Figure 4, the battery 24, the step motor 231 that drives the hour hand 31, the step motor 232 that drives the minute hand 32, the step motor 233 that drives the second hand 33, the step motor 234 that drives the sun wheel 5, the MI step motor 235, and the others are all positioned on the base plate 21 in a way that they do not overlap. The bent portion 58 of the second conductor element 53 of the antenna 50 is positioned at the dashed line shown at the 6 o'clock position on the base plate 21. Therefore, the bent portion 58 of the second conductor element 53 is positioned so as not to overlap with the battery 24 or the stepper motors 231-235 in a plan view.

[0022] [antenna] Antenna 50 is an antenna that receives satellite signals from GPS satellites, and in this embodiment, it is composed of a plate-shaped inverted F antenna. The antenna 50 is positioned so as to overlap the cover glass 15 and the solar panel 25 in a plan view. As shown in Figures 2, 3, and 5, the antenna 50 is composed of a planar first conductor element 52 connected to a power supply unit 56 (described later), a planar second conductor element 53 that overlaps the first conductor element 52 in a plan view, a dielectric 51 placed between the first conductor element 52 and the second conductor element 53, and a short-circuit section 54 that short-circuits the first conductor element 52 and the second conductor element 53. A through-hole 50A is formed at the center of the antenna 50, through which the pointer shafts 35-37 are inserted. Specifically, the through-hole 50A is formed by penetrating the plate-shaped first conductor element 52, the dielectric 51, and the second conductor element 53. The antenna 50 also serves as a support substrate for the film-made solar panel 25.

[0023] The dielectric 51 is a synthetic resin component that serves as the antenna substrate. By using polyphenylene sulfide (PPS), liquid crystal polymer (LCP), polycarbonate (PC), or syndiotactic polystyrene (SPS) as the material for the dielectric 51, electroless plating can be easily applied, the dielectric loss tangent can be lowered, and it can be made suitable as an antenna substrate. As shown in Figure 6, which will be described later, a protrusion is formed on the back surface of the dielectric 51, that is, the surface on the base plate 21 side. The protrusion comprises an inner circumference protrusion 51A formed on the inner circumference side of the sun wheel 5 in a plan view, and an outer circumference protrusion 51B formed on the outer circumference side of the sun wheel 5. The dielectric 51 has the function of pressing the sun wheel 5 against the base plate 21. A recess 51C is formed in the inner circumference protrusion 51A, where an LED substrate (not shown) is placed.

[0024] The first conductor element 52 is a flush conductor and is formed on almost the entire surface of the dielectric 51, i.e., on the solar panel 25 side. The first conductor element 52 also has an open end 57 located on the opposite side of the pointer shaft 4 from the short-circuit portion 54. The first conductor element 52 can also be formed from a thin metal sheet such as copper or an iron alloy, but in this embodiment, it is composed of a metal coating formed on the surface of the dielectric 51. The metal coating can be formed by plating with materials such as copper, silver, nickel, or aluminum.

[0025] The second conductor element 53 is a single metal plate and, like the first conductor element 52, can be formed with a metal coating. However, in this embodiment, it is made of an antimagnetic substrate that also serves as a barrel wheel retainer. The antimagnetic substrate constituting the second conductor element 53 is a conductor plate made of pure iron coated with a nickel film, and as will be described later, it comes into contact with the short-circuit portion 54. The first conductor element 52 functions as a radiating member of the plate-shaped inverted F antenna, and the second conductor element 53 functions as a ground member of the plate-shaped inverted F antenna. Furthermore, as shown in Figures 3, 5, and 6, the second conductor element 53 has a bent portion 58 that is bent on the open end 57 side opposite to the short-circuit portion 54 and on the side opposite to the first conductor element 52, with the distance between it and the first conductor element 52 being the second distance L2. Therefore, the first distance L1 between the first conductor element 52 and the second conductor element 53 in the region where the short-circuit portion 54 is located is smaller than the second distance L2 between the first conductor element 52 and the second conductor element 53 in the region where the open end 57 is located.

[0026] Furthermore, the region where the distance between the first conductor element 52 and the second conductor element 53 is the second distance L2, that is, the region where the bent portion 58 is provided, does not overlap with at least one of the motor that drives the pointer 3 and the battery 24 that supplies power to the motor when viewed along a direction parallel to the pointer axis 4. Therefore, since the thicker motor and battery 24 among the components of the movement 20 do not overlap with the bent portion 58, it is possible to make the watch thinner even if the bent portion 58 is provided on the second conductor element 53.

[0027] As shown in Figures 6 and 7, the short-circuit portion 54 consists of a side short-circuit portion 54A formed on the side surface of the dielectric 51 and a back short-circuit portion 54B formed on the back surface of the dielectric 51, specifically on the bottommost surface of the outer peripheral projection portion 51B. A power supply terminal 55 is formed on the outer peripheral projection 51B, spaced apart from the short-circuit portion 54. This power supply terminal 55 is electrically connected to the first conductor element 52 via the side surface of the dielectric 51. One end of the power supply unit 56 is in contact with the power supply terminal 55. The other end of the power supply unit 56 is in contact with the circuit board 70 and is electrically connected to the receiving IC mounted on the circuit board 70. In Figure 2, the power supply unit 56 penetrates the second conductor element 53 and the dielectric 51 and contacts the first conductor element 52. The power supply unit 56 is a pin-shaped connector made of a conductive material such as metal, and has a built-in coil spring. The biasing force of the coil spring causes it to contact the lower surface of the power supply terminal 55.

[0028] [Antenna performance] Next, the antenna performance of the antenna 50 in this embodiment will be described. Generally, as shown in Figure 9, the performance of a planar antenna tends to deteriorate as its thickness decreases, meaning that the antenna gain decreases. The vertical axis in Figure 9 shows the change in antenna gain relative to an antenna thickness of 1.5 mm. Therefore, in order to obtain a practical antenna gain, a clock incorporating a planar antenna needs to have a thicker antenna, making it difficult to make the clock thinner.

[0029] In this embodiment, the antenna 50 has a first distance L1 on the short-circuit 54 side and a bent portion 58 on the open end 57 side, creating a second distance L2 that is greater than the first distance L1, and increasing the thickness on the open end 57 side. As a result, as shown in Figure 10, the antenna gain is improved to 0.42 dB with the "bent portion" compared to the initial value of a "flat plate" with an antenna thickness of 1.25 mm. The height of the bent portion 58 is 0.5 mm, so the first distance L1 is 1.25 mm and the second distance L2 is 1.75 mm. Therefore, the second distance L2 between the first conductor element 52 and the second conductor element 53 in the region where the open end 57 is located can be made larger than the first distance L1 in the region where the short-circuit 54 is located, thereby improving the antenna gain of the antenna 50. Thus, by providing the bent portion 58, the antenna gain can be brought closer to that of a "flat plate" with an antenna thickness of 1.5 mm.

[0030] Figure 11 shows the simulation results of the current direction of the antenna 50 in this embodiment. As shown in Figure 11, the length from the 12 o'clock position (short-circuited portion 54) to the 6 o'clock position (open end 57) of the antenna electrode is the resonant wavelength, and the antenna 50 resonates at 1 / 4 wavelength. One wavelength of the satellite signal transmitted from a GPS satellite is approximately 19 cm, and 1 / 4 wavelength is 4.76 cm, but it is shortened by the square root of the dielectric constant εr of the substrate of the antenna 50. The diameter of the antenna 50 in this embodiment is 3 cm, and the dielectric constant of the substrate of the antenna 50 is approximately 2.5 to 3.

[0031] Figure 12 shows the simulation results of the electric field distribution at the open end of the antenna 50 in this embodiment. By providing a bent portion 58 at the open end, the resonant space is enlarged, which strengthens the electric field at the open end 57 of the antenna 50 and increases radiation towards the zenith.

[0032] In the electronic clock 1 of this embodiment, the second distance L2 between the first conductor element 52 and the second conductor element 53 in the region where the open end 57 of the built-in antenna 50 is located is greater than the first distance L1 between the first conductor element 52 and the second conductor element 53 in the region where the short-circuit portion 54 is located. Therefore, since a region with a thicker antenna thickness is secured at the open end 57 of the antenna 50, which contributes particularly to radiation, the antenna gain can be improved. In addition, since a bent portion 58 having the second distance L2 is provided in a position that does not overlap with the motor or battery 24, the first distance L1 in the region where the short-circuit portion 54 is located can be made smaller. In other words, the antenna thickness in the region other than the region with the second distance L2 can be reduced, making it possible to make the clock thinner.

[0033] 2. Second Embodiment Next, the electronic clock 1a according to the second embodiment will be described with reference to Figures 13 and 14.

[0034] The electronic clock 1a of this embodiment is the same as the electronic clock 1 of the first embodiment, except that an antenna auxiliary member 60 is arranged between the first conductor element 52 and the second conductor element 53 of the antenna 50a. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0035] The antenna 50a of the electronic clock 1a includes an antenna auxiliary member 60 positioned between the first conductor element 52 and the second conductor element 53, as shown in Figure 13, on the bent portion 58 of the second conductor element 53. More specifically, the antenna auxiliary member 60 is positioned in a region where the distance between the first conductor element 52 and the second conductor element 53 is a second distance L2.

[0036] As shown in Figure 14, the antenna gain of antenna 50a with the antenna support member 60 is 0.98 dB with the antenna support member, compared to 0.42 dB with the bent portion, when the initial value is a "flat plate" with an antenna thickness of 1.25 mm. This represents a significant improvement in antenna performance and also far exceeds the antenna performance of a "flat plate" with an antenna thickness of 1.5 mm shown in Figure 8.

[0037] The antenna auxiliary member 60 is made of a high dielectric material with a dielectric constant higher than that of the dielectric 51 of the antenna 50. That is, since the dielectric constant of the dielectric 51 is about 2 to 4, the antenna auxiliary member 60 is made of a synthetic resin or the like with a dielectric constant of 5 or higher, preferably 8 or higher. When the dielectric constant of the antenna auxiliary member 60 is 8 or higher, since the dielectric constant of the dielectric 51 is about 2 to 4, the dielectric constant of the antenna auxiliary member 60 is more than twice that of the dielectric 51.

[0038] By bending the second conductor element 53 and utilizing the resulting empty space to equip it with an antenna auxiliary member 60, the antenna performance of the antenna 50a can be further improved, making it possible to make the watch even thinner.

[0039] 3. Third Embodiment Next, the electronic clock 1b according to the third embodiment will be described with reference to Figure 15.

[0040] The electronic clock 1b of this embodiment is the same as the electronic clock 1 of the first embodiment, except that the shape of the second conductor element 53b of the antenna 50b is different and an antenna auxiliary member 60b is arranged between the first conductor element 52 and the second conductor element 53b of the antenna 50b. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0041] The antenna 50b of the electronic clock 1b includes an antenna auxiliary member 60b positioned between the first conductor element 52 and the second conductor element 53b, as shown in Figure 15, on the bent portion 58b of the second conductor element 53b.

[0042] The antenna auxiliary member 60b has an arc-shaped portion 61. The second conductor element 53b has a shape that conforms to the shape of the arc portion 61 of the antenna auxiliary member 60b in the region where the distance between the first conductor element 52 and the second conductor element 53b is the second distance L2.

[0043] The antenna support member 60b is formed in the shape of an arc with a central angle of 90 degrees or more in a plan view. Preferably, the antenna support member 60b is formed in the shape of an arc with a central angle close to 180 degrees. By increasing the length of the antenna support member 60b, the antenna gain can be improved more efficiently.

[0044] This configuration allows for further improvement of the antenna performance of antenna 50b, making it possible to make the watch even thinner.

[0045] 4. Fourth Embodiment Next, the electronic clock 1c according to the fourth embodiment will be described with reference to Figure 16.

[0046] The electronic clock 1c of this embodiment is the same as the electronic clock 1 of the first embodiment, except that the shape of the second conductor element 53c of the antenna 50c is different from that of the electronic clock 1 of the first embodiment. The explanation will focus on the differences from the first embodiment described above, and similar matters will be omitted.

[0047] As shown in Figure 16, the antenna 50c of the electronic clock 1c includes a second conductor element 53c in which the bent portion 58c of the second conductor element 53c is processed to be a concave shape that is recessed toward the short-circuit portion 54 when viewed from above.

[0048] By making the bent portion 58c of the second conductor element 53c concave, the region in which the distance between the first conductor element 52 and the second conductor element 53c is the second distance L2 can be widened, thereby improving the antenna gain.

[0049] This configuration allows for further improvement of the antenna performance of the 50c antenna, making it possible to make the watch even thinner. [Explanation of symbols]

[0050] 1,1a,1b,1c...Electronic clock, 2...Dial face, 2B...Date window, 3...Handle, 4...Handle shaft, 5...Date wheel, 10...Case, 11...Case body, 14...Back cover, 15...Cover glass, 20...Movement, 24...Battery, 25...Solar panel, 31...Hour hand, 32...Minute hand, 33...Second hand, 35...Handle shaft, 36...Handle shaft, 37...Handle shaft, 50...Antenna, 50A...Through hole, 51...Dielectric, 52...First conductor element, 53...Second conductor element, 54...Short circuit section, 54A...Side short circuit section, 54B...Back short circuit section, 55...Power supply terminal, 56...Power supply section, 57...Open end, 58...Bent section, 60...Antenna auxiliary member, 61...Arc section, L1...First distance, L2...Second distance.

Claims

1. The pointer shaft to which the pointer is attached, An antenna having a planar first conductor element connected to a power supply section, a planar second conductor element that overlaps with the first conductor element in a plan view, a dielectric disposed between the first conductor element and the second conductor element, and a short-circuit section that short-circuits the first conductor element and the second conductor element, The system comprises a case for housing the aforementioned antenna, The first conductor element has an open end located on the opposite side of the short-circuit portion from the pointer shaft, The first distance between the first conductor element and the second conductor element in the region where the short-circuit portion is located is smaller than the second distance between the first conductor element and the second conductor element in the region where the open end is located. Electronic clock.

2. The region where the distance between the first conductor element and the second conductor element is the second distance does not overlap with at least one of the motor that drives the pointer and the battery that supplies power to the motor when viewed along a direction parallel to the pointer axis. The electronic clock according to claim 1.

3. The antenna further comprises an antenna auxiliary member disposed between the first conductor element and the second conductor element, and made of a material having a higher dielectric constant than the dielectric of the antenna, The antenna auxiliary member is positioned in the region where the distance between the first conductor element and the second conductor element is the second distance. The electronic clock according to claim 1 or claim 2.

4. The aforementioned antenna auxiliary member has an arc-shaped portion, The second conductor element has a shape that follows the shape of the arc portion in the region where the distance between the first conductor element and the second conductor element is the second distance. The electronic clock according to claim 3.

5. The aforementioned antenna auxiliary member is formed in the shape of an arc with a central angle of 90 degrees or more in a plan view. The electronic clock according to claim 4.

6. The first conductor element is a plane-aligned conductor, The second conductor element is a single metal plate and has a bent portion that is bent on the opposite side from the first conductor element, thereby creating a second distance between it and the first conductor element. The electronic clock according to claim 1 or claim 2.

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