JP2019032212A - Electronic clock - Google Patents

Abstract

To provide an electronic clock capable of effectively improving reception sensitivity.SOLUTION: An electronic clock includes: an external case 2 including a storage space part S; a clock display part 3 stored in the storage space part S to display time within the clock; and an antenna 4 that is stored in the storage space part S and receives electric waves from the outside of the external case 2. In the external case 2, a discontinuous part 22 is formed by a pair of separated, opposing opposite faces 21a, 21b in a circumferential direction, and the discontinuous part 22 is formed while opposing a range having a current density up to half or larger than that of a power feed part 42 having the highest current density in the antenna 4 at least in a radial direction of the external case 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic timepiece.

  There is an electronic timepiece having a function of correcting a display time displayed by a timepiece display unit by receiving an external radio wave with an antenna in an outer case. In an electronic wristwatch, a metal exterior case is used rather than a resin because high design is required. It is known that when a metal outer case is used, the outer case surrounds the antenna in a ring shape, so that the receiving sensitivity is lower than that of the antenna alone.

  In view of this, an electronic timepiece has been proposed in which a slit is formed in the outer case to suppress the outer case from surrounding the antenna in an annular shape and to improve reception sensitivity (see Patent Documents 1 and 2).

JP 2002-341057 A JP 2008-128796 A

  By the way, although the receiving sensitivity is improved by forming the slit in the outer case, there is room for further improvement in order to improve the receiving sensitivity.

  The present invention has been made in view of the above, and an object thereof is to propose an electronic timepiece capable of effectively improving reception sensitivity.

  In order to solve the above-described problems and achieve the object, an electronic timepiece according to the present embodiment includes an exterior case having an accommodation space portion, a timepiece display portion that is accommodated in the accommodation space portion and displays the time inside the timepiece. An antenna housed in the housing space and receiving radio waves from the outside of the exterior case, wherein the exterior case has a discontinuous portion formed by a pair of opposed surfaces facing each other in the circumferential direction. The non-continuous portion is formed so as to face a range from the power feeding portion having the highest current density to a portion where the current density becomes half or more in the antenna, at least in a radial direction of the exterior case. It is characterized by that.

  In the electronic timepiece according to the invention, the discontinuous portion is formed in the radial direction so as to be opposed to the range where the current density is high in the antenna, and thus the discontinuous portion is formed in the region where radio wave radiation is strong in the antenna. The reception sensitivity can be effectively improved.

FIG. 1 is an overall configuration diagram of an electronic timepiece according to an embodiment. FIG. 2 is a cross-sectional view of the electronic timepiece according to the embodiment. FIG. 3 is a diagram illustrating the reception sensitivity of the electronic timepiece according to the embodiment. FIG. 4 is a diagram illustrating antenna mounting positions of an electronic timepiece according to a modification. FIG. 5 is a diagram showing antenna mounting positions of an electronic timepiece according to a modification. FIG. 6 is a diagram illustrating antenna mounting positions of an electronic timepiece according to a modification. FIG. 7 is an overall configuration diagram of an electronic timepiece according to a modification. FIG. 8 is a configuration diagram of an antenna of an electronic timepiece according to a modified example and an arrangement diagram of discontinuous portions. FIG. 9 is an overall configuration diagram of an electronic timepiece according to a modification.

  Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

Embodiment
FIG. 1 is an overall configuration diagram of an electronic timepiece according to an embodiment. FIG. 2 is a cross-sectional view of the electronic timepiece according to the embodiment. 2 is a cross-sectional view in the axial direction at the 12 o'clock position T12 in the timepiece display unit 3 shown in FIG. 1 (the same applies to FIGS. 6 and 7), the X direction is the front-rear direction of the electronic timepiece, X1 is the forward direction, and X2 is the backward direction. 2 (the same applies to FIGS. 4 and 5), the Z direction is the vertical direction of the electronic timepiece, Z1 is the upward direction, and Z2 is the downward direction.

  The electronic timepiece 1 according to the embodiment corrects at least the internal time of the timepiece that is timed by the electronic timepiece 1 by receiving radio waves from the outside. The electronic timepiece 1 according to the present embodiment uses a GPS (GLOBAL POSITIONING SYSTEM) radio wave output from a satellite as a radio wave. The GPS radio wave is a radio wave including GPS time information, and is currently of two types: a 1.5 GHz band (1575.42 MHz) and a 1.2 GHz band (1222.70 MHz). As shown in FIGS. 1 and 2, the electronic timepiece 1 includes an exterior case 2, a timepiece display unit 3, an antenna 4, a windshield 5, a ring 6, a back cover 7, a control unit 8, and an actuator 9. A train wheel 10, a battery 11, insulating members 12 and 13, a power feed pin 14, a solar panel 15, and a belt 16. The electronic timepiece 1 in this embodiment will be described as an analog electronic wristwatch with a wristwatch type and a clock display unit 3 that is an analog display type, but it may be a table clock type or a pocket watch type, and the clock display unit 3 is a digital display type. It may be.

  The exterior case 2 is made of a metal, for example, a conductive material such as titanium or a titanium alloy, and constitutes the outermost shell of the electronic timepiece 1. The outer case 2 is formed with a housing space S, and includes a substantially annular portion 21, a discontinuous portion 22, an insulating member 23, and a can 24.

  The substantially annular portion 21 constitutes the accommodating space portion S, and is an annular shape in the present embodiment. The substantially annular portion 21 has openings at the top and bottom, the windshield 5 closes the upper opening, and the back lid 7 closes the lower opening, thereby making the accommodation space S a closed space.

  The non-continuous portion 22 is formed by facing surfaces 21a and 21b that are spaced apart and face each other in the circumferential direction. The non-continuous portion 22 divides the substantially annular portion 21 that is originally annular, thereby interrupting the annular electrical circuit that is generated if the substantially annular portion 21 is essentially annular, and insulates the current that flows annularly. . The discontinuous portion 22 in the present embodiment divides the substantially annular portion 21 at one place, and in the radial direction of the exterior case 2 (the radial direction of the approximately annular portion 21), They are formed to face each other. Further, the discontinuous portion 22 is formed in the radial direction so as to face a portion having the highest current density among two power feeding portions 41 and 41 described later, that is, the antenna 4. Here, the discontinuous portion 22 is formed with respect to the substantially annular portion 21 so that the two power feeding portions 41 and 41 are positioned between the pair of opposed surfaces 21a and 21b when viewed from the radial direction. Yes. Further, the non-continuous portion 22 is formed such that the distance in the circumferential direction between the pair of opposed surfaces 21a and 21b is different in the radial direction. The discontinuous portion 22 is formed to have a taper shape toward the outside in the radial direction, that is, the interval becomes wider toward the outside in the radial direction. Here, if the distance between the opposed surfaces 21a and 21b is constant in the radial direction, the opposed surfaces 21a and 21b of the substantially annular portion 21 are easily coupled as capacitance. When coupled as capacitance, the outer case 2 is electrically connected. The reception sensitivity of the antenna 4 may be lowered. However, in the electronic timepiece 1, since the distance between the opposing surfaces 21 a and 21 b is not constant in the radial direction, the coupling between the opposing surfaces 21 a and 21 b as a capacitance can be suppressed, and the reception sensitivity of the antenna 4 can be reduced. The decrease can be suppressed.

  The insulating member 23 is interposed in the non-continuous portion 22. The insulating member 23 is made of a nonconductive material such as synthetic resin or ceramics, and is formed continuously with the substantially annular portion 21. That is, even if the insulating member 23 is interposed, it is possible to prevent the outer case 2 from being electrically annular. Further, the electronic timepiece 1 can suppress the coupling between the opposing surfaces 21a and 21b as capacitance due to the presence of air between the opposing surfaces 21a and 21b by interposing an insulating layer. it can. Further, in the electronic timepiece 1, since the insulating member 23 interposes the non-continuous portion 22, the step portion is not generated in the substantially annular portion 21, so that it is possible to suppress a decrease in design properties. The insulating member 23 has the same metallic color as that of the substantially annular portion 21 for the purpose of improving the design of the electronic timepiece 1, or emphasizes the contrast of the outer case 2. For this reason, it is possible to obtain a metal color tone having a contrast different from the color of the substantially annular portion 21.

  The can 24 connects the belt 16 and is separated from the front end of the substantially annular portion 21 and protrudes two forwards, and is separated from the rear end and protrudes rearward 2. One is formed. In the electronic timepiece 1, one end of the belt 16 is connected between the pair of cans 24, 24 on the two front sides, and the belt 16 is connected between the pair of cans 24, 24 on the two rear sides. The other end is connected, and the belt 16 is connected to the outer case 2 in an annular shape.

  Here, the belt 16 is made of a nonconductive material such as synthetic resin or ceramics. Since the belt 16 in this embodiment is in contact with the can 24 made of a conductive material, the exterior case 2 can be attached to the belt 16 at a portion other than the non-continuous portion 22 by being made of a non-conductive material. Therefore, it is possible to prevent an annular electric circuit from being formed.

  The clock display unit 3 is housed in the housing space S and displays the time inside the clock. The timepiece display unit 3 includes a dial 31, a second hand 32, a minute hand 33, an hour hand 34, and a date plate 35. The dial 31 is formed in a disk shape, is fixed to the inner peripheral surface forming the accommodation space S of the exterior case 2, and transmits at least light. The dial 31 includes an index 31a, a small window 31b, and a through hole 31c through which the power supply pin 14 passes. The index 31a allows the user to recognize the display time by the hands 32 to 34 based on the relative positions of the second hand 32, the minute hand 33, and the hour hand 34. The indexes 31 a are formed at equal intervals in the circumferential direction with respect to the dial 31. The index 31a in the present embodiment is formed at equal intervals every 30 degrees. The small window 31b is formed at a position facing the date plate 35 in the vertical direction of the dial 31 and penetrates the dial 31 in the vertical direction. The small window 31 b in the present embodiment has a rectangular shape, and is formed at the “3 o'clock” position on the dial 31. The hands 32 to 34 are rotatably supported by a base (not shown), and rotate coaxially on the upper side of the dial 31, for example, at the center of the dial 31. Depending on the relative position of the hands 32 to 34 with respect to the index 31 a on the dial 31, the second hand 32 indicates “second” of the display time, the minute hand 33 indicates “minute” of the display time, and the hour hand 34 indicates the display time. Of these, it refers to “time”. Each of the hands 32 to 34 in the present embodiment has the same length from the center of the dial 31 in the radial direction as the second hand 32 and the minute hand 33, and the hour hand 34 is formed short. The date plate 35 is a rotating plate, is rotatably supported by a frame (not shown), and rotates on the lower side of the dial 31. A part of the date plate 35 is exposed to the upper side of the dial 31 through the small window 31b. The date plate 35 is formed with a plurality of characters in a series of character groups for identifying a calendar at equal intervals in the circumferential direction.

  The antenna 4 is accommodated in the accommodating space S and receives GPS radio waves from the outside of the exterior case 2. The antenna 4 is formed in a shape corresponding to the frequency characteristics of the received GPS radio wave. The antenna 4 in the present embodiment is a dipole that is one of linear antennas, and is disposed between the dial 31 and the windshield 5. As shown in FIG. 2, the antenna 4 is attached to the surface of the windshield 5 that faces the dial 31, that is, the lower surface 5 a. The antenna 4 includes two power feeding portions 41 and 41 and two antenna elements 42 and 42. Here, the antenna element 42 is made of a dielectric material such as copper, copper alloy, aluminum, aluminum alloy, silver, or gold.

  The power feeding unit 41 outputs an antenna output signal based on the GPS radio wave received by the antenna element 42 to the control unit 8. The power feeding section 41 is formed at one end in the circumferential direction of the antenna element 42 and is formed integrally with the antenna element 42. The power feeding unit 41 is electrically connected to the main board 81 of the control unit 8 by power feeding pins 14. The two power feeding portions 41 and 41 are formed adjacent to each other in the circumferential direction. The two power feeding portions 41 and 41 are formed to face the 12 o'clock position T12 in the timepiece display portion 3 in the radial direction.

  The antenna element 42 is a portion that receives GPS radio waves, and is formed in an arc shape along the circumferential direction. One antenna element 42 is formed to extend from the power feeding part 41 on the clockwise side along the clockwise direction in the circumferential direction. The other antenna element 42 is formed to extend from the counterclockwise feeding portion 41 along the counterclockwise direction in the circumferential direction. Here, the length of the antenna element 42 is set according to the received GPS radio wave, and is set to ¼ of the wavelength λ of the received GPS radio wave, that is, 1 / 4λ.

  The windshield 5 closes the accommodation space S, and protects the clock display 3 and the antenna 4. The windshield 5 is fixed to the exterior case 2 so as to face the clock display unit 3 in the upward direction of the clock display unit 3. The windshield 5 is made of a material that transmits light for the user to recognize the timepiece display unit 3 and transmits GPS radio waves, such as glass. The windshield 5 in this embodiment is fixed to the exterior case 2 via an insulating member 12 such as a non-conductive material, for example, a rubber O-ring.

  The ring 6 is accommodated in the accommodation space S and is a decorative board. The ring 6 is disposed between the dial 31 and the windshield 5 and is formed in an annular shape. The ring 6 is attached to the upper surface of the dial 31, and the outer peripheral surface is in contact with the inner peripheral surface of the exterior case 2. The ring 6 has a through hole 6a through which the power feed pin 14 passes. The ring 6 suppresses an extreme step in the vertical direction between the outer case 2 and the dial 31 when the electronic timepiece 1 is viewed from the viewing side, that is, the side from which the timepiece display unit 3 can be viewed. The continuity from 2 to the dial 31 is improved.

  The back cover 7 closes the accommodation space S, and protects the control unit 8, the actuator 9, and the like. The back cover 7 is fixed to the outer case 2 so as to face the timepiece display unit 3 in the downward direction of the timepiece display unit 3. The back cover 7 in the present embodiment is made of metal. The back cover 7 in this embodiment is fixed to the exterior case 2 via an insulating member 13 such as a non-conductive material, for example, a rubber O-ring. As a result, the back cover 7 is not electrically connected to the exterior case 2 and is in a disconnected state, and the exterior case 2 forms an annular electric circuit via the back cover 7 at a portion other than the discontinuous portion 22. Can be prevented.

  The control unit 8 is accommodated in the accommodation space S and controls the electronic timepiece 1, and is disposed on the lower side of the timepiece display unit 3. The control unit 8 includes a main board 81, a sub board 82, a receiving circuit 83, a control circuit 84, a main board press 85, a sub board press 86, and conduction members 87 and 88. The control unit 8 only needs to be able to achieve the required functions, and the hardware configuration is the same as or almost the same as the hardware configuration of a known microcomputer.

  The main board 81 controls main functions of the electronic timepiece 1. The main board 81 in this embodiment performs reception control by the antenna 4, drive control of the actuator 9, power control of the electronic timepiece 1, charge / discharge control for the battery 11, and the like. The main board 81 is mounted with a receiving circuit 83 and a control circuit 84, is mounted with a battery 11, and is electrically connected to the battery 11. The main board 81 is held by a main board presser 85. The main board 81 is electrically connected to the solar panel 15 via the conductive members 87 and 88.

  The sub-board 82 controls additional functions of the electronic timepiece 1. The sub board 82 in this embodiment performs drive control of the solar panel 15 and the like. The sub board 82 is electrically connected to the main board 81 via a conducting member 87. The sub board 82 is electrically connected to the solar panel 15 through the conductive member 88.

  The receiving circuit 83 performs reception control by the antenna 4. The receiving circuit 83 is electrically connected to the antenna 4 via the antenna 4 and the power feed pin 14. The receiving circuit 83 receives an alternating current that is an output based on the GPS radio wave received by the antenna 4. The receiving circuit 83 is electrically connected to the control circuit 84 and outputs an output based on GPS radio waves to the control circuit 84 as an antenna output signal. Note that the receiving circuit may also include a balun circuit (balance-unbalance conversion circuit).

  The control circuit 84 performs drive control of the actuator 9 and correction control of the clock internal time. The control circuit 84 outputs drive pulses so that the second hand 32, the minute hand 33, and the hour hand 34 become display times corresponding to the clock internal time based on the clock internal time measured by a clock unit (not shown). That is, the control unit 8 drives and controls the actuator 9 to rotate the second hand 32, the minute hand 33, and the hour hand 34 in the clockwise direction so that the display time corresponds to the clock internal time. Based on the antenna output signal, the control circuit 84 replaces the clock internal time with GPS time information included in the GPS radio wave, that is, corrects the clock internal time based on the GPS time information. Of the control circuit 84, the drive circuit that controls the drive of the actuator 9 may be mounted on the sub-board 82 that is closer to the actuator 9 than the main board 81, as a separate component. The drive circuit is controlled in accordance with a signal from the control circuit 84.

  The main board presser 85 is for fixing the main board 81 to the exterior case 2. The main board holder 85 is made of metal, that is, made of a conductive material, and has a ground spring 85a. The ground spring 85 a is formed so as to protrude from the lower side of the main board presser 85 and is connected to the back cover 7. Here, since the back cover 7 is made of metal, the back cover 7 is electrically connected to the main board 81 via the main board press 85 and functions as the GND of the main board 81 and the sub board 82. Since the back cover 7 is not electrically connected to the outer case 2 and is in a disconnected state, the outer case 2 can be prevented from forming an annular electric circuit via the ground spring 85a. The ground spring 85a may be in contact with the outer case 2. Also in this case, since the electrical connection point between the control unit 8 and the outer case 2 is one place of the earth spring 85a, the outer case 2 is prevented from forming an annular electric circuit via the earth spring 85a. be able to.

  The sub board presser 86 is for fixing the sub board 82 to the outer case 2. The sub board presser 86 is made of a metal, that is, made of a conductive material, and is arranged to face the main board 81 with the battery 11 in the vertical direction.

  The actuator 9 is housed in the housing space S and rotates the hands 32 to 34 on the dial 31. The actuator 9 is, for example, an electromagnetic motor that is intermittently driven, and is connected to the needles 32 to 34 via the train wheel 10.

  The train wheel 10 is a reduction mechanism that is accommodated in the accommodation space S and is interposed between the actuator 9 and each of the hands 32 to 34. By reducing the rotational speed of the actuator 9, the second hand 32 is moved every 60 seconds. The minute hand 33 is rotated once every 60 minutes, and the hour hand is rotated once every 12 hours.

  The battery 11 is housed in the housing space S and is a part of the power source of the electronic timepiece 1. The battery 11 in the present embodiment is a chargeable / dischargeable secondary battery, and supplies power to each device of the electronic timepiece 1 via the main board 81.

  The solar panel 15 is housed in the housing space S and is a part of the power source of the electronic timepiece 1. The solar panel 15 generates power using light incident on the accommodation space S from the outside of the electronic timepiece 1. The solar panel 15 is an aggregate of photovoltaic elements, and the light receiving surface is disposed on the lower side of the dial 31 so as to face the dial 31. The solar panel 15 is transmitted through the windshield 5 and the dial 31. It generates electricity by receiving the received light. The generated electric power is supplied to the main board 81 and the sub board 82 via the conductive members 87 and 88, and is supplied to each device of the electronic timepiece 1 or charged to the battery 11.

  Next, reception of radio waves by the electronic timepiece 1 in the present embodiment will be described. The control unit 8 receives GPS radio waves when correcting the clock internal time. Specifically, an alternating current is generated in the antenna element 42 by the GPS radio wave output from the satellite. The alternating current is output from the power feeding unit 41 to the receiving circuit 83 of the control unit 8. At this time, the current density of the antenna 4 is the highest in the power feeding part 41, and the end of the antenna element 42 opposite to the power feeding part 41 side is the lowest. The antenna 4 changes the intensity of radio wave radiation according to the radio wave density. Therefore, the strength of radio wave radiation of the antenna 4 is the highest in the power feeding portion 41, and the end of the antenna element 42 opposite to the power feeding portion 41 side is the lowest. Further, when the discontinuous portion 22 is not formed on the outer case 2, an image antenna is generated on the opposite side of the antenna 4 with the outer case 2 interposed therebetween. In the image antenna, the magnetic field generated by the current flowing in the direction opposite to that of the antenna 4 acts to cancel the magnetic field generated when the antenna 4 is supplied with electric power. Thereby, if the antenna 4 is arrange | positioned in the accommodation space part S of the exterior case 2 in which the non-continuous part 22 is not formed, reception sensitivity will fall. On the other hand, when the discontinuous portion 22 is formed in the outer case 2, a loop current does not flow because an electrically separated portion is formed in the outer case 2, and as a result, no image antenna is generated. , A decrease in reception sensitivity is suppressed.

  Here, the relationship between the formation position of the discontinuous portion 22 and the reception sensitivity of the antenna 4 will be described. FIG. 3 is a diagram illustrating the reception sensitivity of the electronic timepiece according to the embodiment. In FIG. 3, the vertical axis represents reception sensitivity (C / N (dB)), and the horizontal axis represents each satellite. In order to explain the relationship between the formation position of the discontinuous portion 22 and the reception sensitivity of the antenna 4, the exterior case 2, the discontinuous portion 22, and the antenna 4 were simply reproduced on the substrate. Specifically, two dipole antennas were formed on a substrate, and two substantially circular copper foils were formed outside the dipole antenna. One is a non-continuous portion feeding portion side forming substrate in which a portion of the copper foil facing the feeding portion of the dipole antenna in the radial direction is missing (FIG. A). The other is a non-continuous portion opposite side formation substrate in which the portion facing the feeding portion of the dipole antenna is missing in the radial direction with the center of the copper foil interposed therebetween (B in the same figure). As shown in the figure, when comparing the discontinuous part feeding part side forming substrate and the discontinuous part opposite forming substrate, the discontinuous part feeding part side forming substrate is discontinuous part in any GPS radio wave received from any satellite. It is higher than the opposite side formation substrate. That is, the relationship between the formation position of the non-continuous portion 22 and the reception sensitivity of the antenna 4 is a portion of the antenna 4 that is higher than a portion where the current density of the antenna 4 is low, that is, a portion where the intensity of radio wave radiation of the antenna 4 is weak. The receiving sensitivity of the antenna 4 can be improved by forming the discontinuous portion 22 so as to face the stronger portion in the radial direction.

  As described above, in the electronic timepiece 1 according to the present embodiment, the discontinuous portion 22 is formed in the antenna 4 in a range where the radio wave emission is strong because the discontinuous portion 22 is formed facing the range where the current density is high in the antenna 4. Thus, the receiving sensitivity can be effectively improved. Moreover, since the electronic timepiece 1 according to the present embodiment forms the discontinuous portion 22 so as to face the power feeding portion 41 having the highest current density among the antennas 4, the discontinuous portion is formed in the portion of the antenna 4 where radio wave radiation is strongest. 22 is formed, and the receiving sensitivity can be further improved.

  In the electronic timepiece 1 according to the present embodiment, the discontinuous portion 22 is formed to face the 12 o'clock position T12 of the timepiece display portion 3 in the radial direction. The twelve o'clock position T12 of the clock display unit 3 is the position most watched by the user, and the discontinuous portion 22 is opposed to the twelve o'clock position T12 in the radial direction so that the discontinuous portion 22 is included in the central visual field of the user. Can be made. In many cases, a user watches a change or contrast difference in the peripheral visual field surrounded by the central visual field. Accordingly, when the electronic timepiece 1 is visually recognized, the discontinuous portion 22 is often viewed in the central visual field, and is less visible in the peripheral visual field. Therefore, the user looks at the electronic timepiece from the 12 o'clock position T12. It is possible to suppress transfer to one other part. Thereby, the electronic timepiece 1 can suppress that it becomes difficult to visually recognize display time compared with the electronic timepiece in which the discontinuous part 22 is not formed.

  In the electronic timepiece 1 in the above embodiment, the antenna 4 is attached to the windshield 5, but the invention is not limited to this, and it is sufficient that the electronic timepiece 1 is disposed in the accommodation space S. FIG. 4 is a diagram illustrating antenna mounting positions of an electronic timepiece according to a modification. FIG. 5 is a diagram showing antenna mounting positions of an electronic timepiece according to a modification. FIG. 6 is a diagram illustrating antenna mounting positions of an electronic timepiece according to a modification. The antenna 4 may be attached to the ring 6 as shown in FIG. In this case, the ring 6 is attached to the surface facing the windshield 5 in the vertical direction, that is, the upper surface 6b. Further, the antenna 4 may be attached to the inside of the ring 6 as shown in FIG. In this case, the ring 6 has an L-shaped cross section in the radial direction, and both end portions when viewed from the tangential direction are in contact with the inner peripheral surface of the outer case 2 and the upper surface of the dial 31, respectively. A space is formed by the ring 6, the outer case 2, and the dial 31. In the timepiece display unit 3, an antenna base 36 is formed between the dial 31 and the ring 6. The antenna base 36 is formed in an arc shape or a ring shape along the circumferential direction. The antenna 4 is attached to a surface of the antenna base 36 that faces the ring 6 in the vertical direction, that is, the upper surface 36a. Moreover, the antenna 4 may be attached to the space part below the dial 31 among the accommodation space parts S, as shown in FIG. In the space portion below the dial 31, for example, an antenna base 89 is formed on the main board 81 of the control unit 8. The antenna base 89 is formed in an arc shape or a ring shape along the circumferential direction. The antenna 4 is attached to a surface of the antenna base 89 that faces the dial 31 in the vertical direction, that is, the upper surface 89a. Since the width in the radial direction of the ring 6 can be reduced compared to the case where the antenna 4 is attached to the upper surface 6b of the ring 6 or the inside of the ring 6, the diameter of the solar panel 15 can be increased. The light receiving surface of the panel 15 can be enlarged. Moreover, the designability can be improved by reducing the width of the ring 6 in the radial direction.

  In addition, the electronic timepiece 1 in the above embodiment is formed with the non-continuous portion 22 exposed to the outside, but is not limited thereto. FIG. 7 is an overall configuration diagram of an electronic timepiece according to a modification. As shown in FIG. 7, the outer case 2 has a tip 25 formed at a position facing the twelve o'clock position T12 in the timepiece display unit 3 in the radial direction. The tip 25 covers the upper side of the portion of the substantially annular portion 21 that faces the 12 o'clock position T12 in the radial direction. Accordingly, the non-continuous portion 22 is positioned on the lower side of the tip 25 in the vertical direction. That is, the discontinuous portion 22 is covered with the tip 25 on the viewing side of the timepiece display portion 3. Thereby, since it can prevent that the non-continuous part 22 is exposed outside, the fall of the design property of the electronic timepiece 1 can be suppressed by exposing the non-continuous part 22 to the outside. Here, the tip 25 is made of a nonconductive material such as a synthetic resin or ceramics, and is in contact with the substantially annular portion 21 made of a conductive material. Accordingly, it is possible to prevent the outer case 2 from forming an annular electric circuit via the tip 25 in a portion other than the non-continuous portion 22.

  Moreover, although the electronic timepiece 1 in the said embodiment forms the discontinuous part 22 facing the electric power feeding part 41 with the highest current density among the antennas 4, it is not limited to this. The discontinuous portion 22 may be formed so as to face the power supply portion 41 having the highest current density and the range up to a portion where the current density becomes half or more in the antenna 4. If the relationship between the change in the distance from the power feeding part 41 of the antenna element 42 and the change in the current density is proportional, the discontinuous part 22 is connected to the part of the antenna element 42 that is half the distance from the power feeding part 41. It will be formed facing in the range. This is because the discontinuous portion 22 is simply formed in the outer case 2 even if the feeding portion 41 having the highest current density and the portion where the current density is less than half of the antenna 4 are opposed to the discontinuous portion 22. This is because the reception sensitivity is not greatly improved.

  Moreover, although the electronic timepiece 1 in the above embodiment has one discontinuous portion 22 formed on the exterior case 2, the present invention is not limited to this, and the power feeding portion having the highest current density among the antennas 4. As long as at least one non-continuous portion 22 is formed opposite to a range where the current density is 41 or more, a plurality of non-continuous portions 22 may be formed with respect to the outer case 2. .

  Moreover, although the electronic timepiece 1 in the present embodiment has been described using the antenna 4 as a dipole antenna, the present invention is not limited to this. The electronic timepiece 1 may be a loop antenna that is one of linear antennas. FIG. 8 is a configuration diagram of an antenna of an electronic timepiece according to a modified example and an arrangement diagram of discontinuous portions. The antenna 4 of the electronic timepiece 1 in the modified example is a loop antenna, and includes two power feeding portions 41 and 41 and one antenna element 42 as shown in FIG. The power feeding portion 41 is formed to face the 12 o'clock position T12 in the timepiece display portion 3 in the radial direction.

  The antenna element 42 is formed in an annular shape along the circumferential direction from one feeding part 41 to the other feeding part 41 facing in the circumferential direction along the circumferential direction. The two power feeding portions 41 and 41 are formed at positions facing the 12 o'clock position T12 in the timepiece display portion 3 in the radial direction. Here, the length of the antenna element 42 is set to the length of the wavelength λ of the received GPS radio wave.

  The discontinuous portions 22 and 26 of the electronic timepiece 1 in the modified example are formed at two places with respect to the exterior case 2. Similarly to the embodiment, the discontinuous portion 22 is formed to face the two power feeding portions 41 and 41 in the radial direction, that is, to face the 12 o'clock position T12 in the timepiece display portion 3. The discontinuous portion 26 is formed by facing surfaces 21c and 21d that are spaced apart and face each other in the circumferential direction, and is formed facing the 6 o'clock position T6 in the timepiece display portion 3 in the radial direction. That is, the discontinuous portion 26 is formed in a portion facing the power feeding portion 41, that is, a portion facing the discontinuous portion 22 across the center of the exterior case 2 in the radial direction. Note that an insulating member 27 is interposed in the discontinuous portion 26.

  When the antenna 4 is a loop antenna, the antenna characteristics are as if two dipole antennas were opposed to each other in the radial direction. That is, the antenna 4 in the modified example has an apparent power feeding part in a portion facing the two power feeding parts 41 and 41 with the center of the outer case 2 interposed therebetween, and thus the apparent power feeding in the radial direction. Since the discontinuous part 26 is formed facing the part, the discontinuous parts 22 and 26 are formed facing the feeding part 41 having the highest current density and the apparent feeding part, respectively, for each dipole antenna. Thus, the reception sensitivity can be further improved as compared with the case where one discontinuous portion 22 is formed.

  The antenna 4 may be a monopole antenna that is one of linear antennas, or may be a patch antenna, a chip antenna, an inverted F antenna, a slot antenna, or the like.

  Further, the back cover 7 may be made of resin or ceramics. In this case, since the back cover 7 is made of a synthetic resin or ceramic that is a non-conductive material, the receiving sensitivity of the antenna 4 can be further improved. Further, the back cover 7 can be directly fixed to the outer case 2 without using the insulating rubber 13. In addition, even if the back cover 7 is made of metal, for the purpose of improving the design and improving the receiving sensitivity of the antenna 4, a central member made of synthetic resin, ceramics, glass, which is a non-conductive material, And an outer peripheral member formed of a metal that is a conductive material surrounding the outer periphery of the central member. In this case, the back cover 7 is preferably formed in a substantially annular shape by forming the pair of opposed surfaces on the outer peripheral member to form a back cover discontinuous portion. Thereby, it can prevent that an outer peripheral member forms a cyclic | annular electric circuit. Furthermore, when directly fixing the back cover 7 to the exterior case 2, it is preferable that the non-continuous portions 22 and 26 and the back cover non-continuous portions be opposed to each other in the vertical direction. In this case, since the outer peripheral member is not positioned below the non-continuous portions 22 and 26, the outer case 2 forms an annular electric circuit via the back cover 7 at a portion other than the non-continuous portions 22 and 26. Can be prevented.

  The belt 16 may be made of a conductive material such as metal. FIG. 9 is an overall configuration diagram of an electronic timepiece according to a modification. When the belt 16 is made of metal, as shown in FIG. 9, spaces S1 to S3 may be formed between the belt 16 and the exterior case 2 facing the end of the belt 16 on the upper side. . In the electronic timepiece 1 in the modified example, a non-conductive material such as a synthetic resin or ceramics is provided in the space portions S1 and S2 where the belt 16 and the two cans 24 and 24 facing the end portion of the belt 16 on the upper side face each other. An insulating member 28 made of a material is interposed, and the belt 16 is fixed to the two cans 24 and 24 via the insulating member 28. Here, on the upper side of the outer case 2, a space S <b> 3 is formed at a position where the belt 16 faces the substantially annular portion 21 and the discontinuous portion 22. In this case, the belt 16 and the two canisters 24 are not electrically connected, and the belt 16 and the substantially annular portion 21 are not electrically connected. It is possible to prevent an annular electric circuit from being formed via the. In the electronic timepiece 1 in the modified example, an insulating member may be interposed in the space portion S3 in the same manner as the space portions S1 and S2. If the belt 16 is made of metal, the two cans 24 may be made of a non-conductive material such as synthetic resin or ceramics. In this case, the belt 16 can be directly fixed to the two cans 24 and 24 in a state where the space S3 is formed at a position where the belt 16 and the substantially annular portion 21 and the discontinuous portion 22 face each other. Further, when the two discontinuous portions 22 and 26 are formed on the outer case 2 (see FIG. 8), the outer surface facing the belt 16 and the end portion of the belt 16 on the vertical direction side is the same as described above. Space portions S1 to S3 are formed between the case 2 and the case 2, respectively. In this case, since the space portion S3 is formed at a position where the belt 16 and the substantially annular portion 21 and the discontinuous portion 26 face each other on the lower side of the exterior case 2, the exterior case 2 is annularly formed via the belt 16. It is possible to prevent the electrical circuit from being formed. Further, even in the case where only the discontinuous portion 22 is formed in the outer case 2, for the purpose of improving the design, as shown in FIG. 9, the belt 16 and the end portion of the belt 16 on the lower side Space portions S1 to S3 may be formed between the facing outer cases 2 respectively.

  Further, when the belt 16 is made of metal, as shown in FIGS. 1 and 7, a portion of the one end portion of the belt 16 that faces the discontinuous portion 22 in the radial direction is a belt-side insulating member 16a. You may comprise with nonelectroconductive materials, such as a synthetic resin and ceramics. The belt-side insulating member 16 a divides the belt 16 in the direction of the two cans 24, 24, that is, in the width direction of the electronic timepiece 1. In this case, the portion of the belt 16 that is opposed to the belt-side insulating member 16a is not electrically connected, and the substantially annular portion 21 is not electrically connected via the belt 16, so the portion other than the discontinuous portion 22 is not connected. The outer case 2 can be prevented from forming an annular electric circuit via the belt 16. The width in the circumferential direction of the belt-side insulating member 16a may be the same, wide, or narrow as the width in the circumferential direction of the discontinuous members 22 and 26. Further, in the case where the two discontinuous portions 22 and 26 are formed on the outer case 2 and the belt 16 is made of metal, as shown in FIG. The portions facing the non-continuous portions 22 and 26 in the direction may be belt-side insulating members 16a and may be made of a non-conductive material such as synthetic resin or ceramics.

  Further, the tip 25 is formed in the outer case 2 at a position facing the twelve o'clock position T12 in the timepiece display unit 3 in the radial direction, but for the purpose of improving the design, the twelve o'clock position T12. As well as a position facing the 6 o'clock position T6 (particularly when the discontinuous portion 26 is formed at a position facing the 6 o'clock position T6). Further, the tip 25 may be formed at a position facing the 3 o'clock position and a position facing the 9 o'clock position.

  Further, the tip 25 faces the non-continuous portion 22 (including the case where it faces the non-continuous portion 26 as described above) in the vertical direction, but may be made of a conductive material, for example, metal. When the tip 25 is made of metal, a space portion may be formed between the tip 25 and the non-continuous portion 22. For example, an insulating member made of a nonconductive material such as synthetic resin or ceramics may be interposed in the space between the tip 25 and the non-continuous portion 22. Further, the tip 25 may be formed integrally with the belt 16, that is, as a part of the belt 16. In this case, if the belt 16 is made of metal, the space portions S1 to S3 are formed between the outer case 2 and the space portion is formed between the tip 25 and the discontinuous portion 22 or insulated from the space portion. A member will be interposed. The tip 25 may be formed integrally with the two cans 24, 24, that is, the two cans 24, 24 may be connected. In this case, a space portion is formed between the tip 25, the tip ring 25, the two cans 24, 24, and the discontinuous portion 22, or an insulating member is interposed in the space.

DESCRIPTION OF SYMBOLS 1 Electronic timepiece 2 Exterior case 21 Substantially annular part 22, 26 Non-continuous part 21a, 21b, 21c, 21d Opposing surface 23, 27 Insulating member 24 kan 25 Pointer 3 Clock display part 31 Dial 32 Second hand 33 Minute hand 34 Hour hand 35 Day Plate 36 Antenna base 4 Antenna 41 Feeding part 42 Antenna element 5 Windshield 6 Ring 7 Back cover 8 Control part 9 Actuator 10 Wheel train 11 Battery 12, 13 Insulating member 14 Feeding pin 15 Solar panel 16 Belt S Housing space part S1 to S3 Space T6 6 o'clock position T12 12 o'clock position

Claims (7)

An exterior case having a housing space;
A clock display unit that is housed in the housing space and displays a clock internal time;
An antenna housed in the housing space and receiving radio waves from outside the exterior case;
With
The outer case has a discontinuous portion formed by a pair of facing surfaces that are spaced apart from each other in the circumferential direction.
The discontinuous portion is formed at least in the radial direction of the outer case, and is opposed to a range of the antenna to a portion where the current density is the highest and a portion where the current density is half or more.
An electronic timepiece characterized by that. The electronic timepiece according to claim 1,
The discontinuous portion is formed to face the power feeding portion at least in the radial direction.
Electronic clock. The electronic timepiece according to claim 1 or 2,
The discontinuous portion is formed to face the 12 o'clock position of the timepiece display portion at least in the radial direction.
Electronic clock. The electronic timepiece according to claim 3,
The outer case has a tip formed at a position facing the 12 o'clock position in the timepiece display portion in the radial direction,
The discontinuous portion is covered with the tip on the viewing side of the timepiece display portion. The electronic timepiece according to any one of claims 1 to 4,
The pair of facing surfaces are electronic timepieces that are formed with different circumferential intervals in the radial direction. In the electronic timepiece according to any one of claims 1 to 5,
The non-continuous part intervenes an insulating member,
Electronic clock. The electronic timepiece according to any one of claims 1 to 6,
The antenna is a loop antenna;
The power feeding portion is formed facing the 12 o'clock position in the timepiece display portion in the radial direction,
The discontinuous portion is formed to face the 12 o'clock position and the 6 o'clock position of the timepiece display portion at least in the radial direction.
Electronic clock.

Images