JP2013050339A - Electronic timepiece with built-in antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic timepiece with a built-in antenna which can maintain the receiving performance of a GPS at a sufficiently high level while achieving miniaturization of an antenna and facilitates the assembling and adjusting works without reducing the degree of freedom in design of a dial plate.SOLUTION: An electronic timepiece with a built-in antenna includes: a cylindrical outer case 80 of which at least a part is formed of a nonconductive member; a movement 38 which includes a drive mechanism 30 housed in the outer case 80; a time display part which displays time inside the outer case 80; an annular antenna body 40 housed in the outer case 80; and a pair of power feeding electrodes 40a and 40b which feed electric power to the antenna body 40. The antenna body 40 is disposed along the outer edge of a dial plate 11, and the movement 38 has holding parts 90 for holding the antenna body at a plurality of places along the outer edge of the time display part.

Description

  The present invention relates to an electronic timepiece with a built-in antenna.

  Patent Document 1 discloses an antenna used for an electronic device or an electronic timepiece that is formed in a loop shape along the outer periphery of the lower surface of the timepiece glass. In addition, it is said that signal reception can be reliably performed while sufficiently securing the antenna length. In particular, Patent Document 1 also mentions that the feeding electrode of the loop antenna is arranged at the top of the dial, that is, at the 12 o'clock position.

  Further, Patent Document 2 discloses a structure in which a case of a receiver functions as a loop antenna with respect to a wrist-portable receiver. The loop antenna disclosed in Patent Document 2 has a shape that loops in the vertical or horizontal direction with respect to the arm. Specifically, the loop antenna is used with respect to the arm at the time of wearing using one side surface portion or both surface portions of the case. It has a shape that loops once or twice in the vertical or horizontal direction, connects two upper and lower semicircular antennas, and forms a feeding port at the other end.

JP-A-9-307329 Japanese Patent Laid-Open No. 9-247006

However, in order to ensure good reception using a conventional antenna, it is desirable that the antenna is on the lower surface of the cover glass and on the same surface as the dial. As a result, there is a problem that the dial space is occupied by the antenna, and the degree of freedom in designing the dial is reduced.
Conventionally, an antenna is attached to an exterior part and the exterior part is assembled and then adjusted with the receiving circuit. As a result, if the adjustment is not successful, it is necessary to remove the exterior parts and adjust the position of the antenna, and the work is very complicated.

  The present invention has been made in view of the above-described circumstances, and in receiving satellite signals in GPS (Global Positioning System), while reducing the size of the antenna and maintaining the reception performance sufficiently high, An object of the present invention is to provide an electronic timepiece with a built-in antenna that can be easily assembled and adjusted without lowering the degree of freedom in designing the plate.

  In order to solve the above-described problems, an electronic timepiece with a built-in antenna according to the present invention includes a cylindrical outer case at least partially formed of a non-conductive member, and a movement that is housed in the outer case and includes a drive mechanism. A time display unit that is arranged on the movement and displays the time inside the outer case, and is housed in the outer case and includes an annular antenna body and a pair of feeding electrodes that feed the antenna body, The antenna body is disposed along an outer edge of the time display unit, and the movement includes a holding unit that holds the antenna body at a plurality of locations along the outer edge of the time display unit. To do.

  In this electronic timepiece with built-in antenna, the annular antenna body is held by a holding portion provided in the movement. Therefore, the receiving circuit can be adjusted in a state where the antenna is held by the movement before the antenna and the movement are stored in the outer case. As a result, the efficiency of the adjustment process and the assembly process can be improved.

  As the “non-conductive member”, materials other than metal, such as ceramics and plastics, can be used. Further, the “time display unit” includes a dial of a clock, and the time display on the dial includes a display by hands and a digital display such as liquid crystal. Examples of the pointer include an hour hand, a minute hand, and a second hand.

  Furthermore, the phrase “along the outer edge” includes a case where it is arranged in the plane of the time display unit and a case where it is arranged around. In addition, “annular” includes a circular shape or a substantially quadrangular shape, and includes an open ring shape (for example, C type) that is partially open, and a closed ring shape (for example, O type) that is entirely closed.

  Further, the holding portion may be formed integrally with the movement. For example, it is formed by plastic molding. Moreover, it is preferable that the said antenna body and the said holding | maintenance part are arrange | positioned around the said time display part. Thereby, the antenna built-in type electronic timepiece can be miniaturized. Furthermore, the holding part may be provided with a claw-like part for holding the antenna body. The antenna body can be held by engaging the antenna body with the claw-shaped portion.

  Furthermore, you may make it cover the said antenna body and the said holding | maintenance part with resin-made cyclic | annular cover members, for example. By this cover member, it is possible to prevent the antenna body and the holding portion from being exposed, and it is possible to design the surface of the cover member, thereby preventing a reduction in the degree of freedom in design.

  A flange portion may be provided on the annular inner peripheral portion of the antenna body, and the antenna may be held by engaging the flange portion with the holding portion. In the case where the antenna body has a spiral shape formed by winding a wire in a coil shape, the holding portion may be a pair of holding portions that sandwich the antenna body having a spiral shape.

1 is an overall view of a GPS system including an antenna built-in electronic timepiece 100 (electronic timepiece 100) according to a first embodiment of the present invention. 2 is a plan view of the electronic timepiece 100. FIG. 2 is a partial cross-sectional view of the electronic timepiece 100. FIG. 2 is an exploded perspective view of a part of the electronic timepiece 100. FIG. 2 is a block diagram showing a circuit configuration of the electronic timepiece 100. FIG. 3 is a plan view showing positions of power supply electrodes in the electronic timepiece 100. FIG. FIG. 6 is an explanatory diagram showing a relationship between a mounting state of the electronic timepiece 100 and a position of a power feeding electrode. 4 is a perspective view showing a coordinate system related to a radiation pattern of an antenna body 40 of the electronic timepiece 100. FIG. FIG. 6 is a diagram showing a radiation pattern on the XY plane of the antenna body 40 of the electronic timepiece 100. 6 is a diagram showing a radiation pattern in the ZY plane of the antenna body 40 of the electronic timepiece 100. FIG. It is a top view of the electronic timepiece 200 (electronic timepiece 200) with a built-in antenna which concerns on 2nd Embodiment of this invention. It is a partial cross section figure of the electronic timepiece 200 (electronic timepiece 200) with a built-in antenna which concerns on 2nd Embodiment of this invention. It is a partial cross section figure of the electronic timepiece 300 (electronic timepiece 300) with a built-in antenna which concerns on 3rd Embodiment of this invention.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. However, in each figure, the size and scale of each part are appropriately changed from the actual ones. Further, since the embodiments described below are preferable specific examples of the present invention, various technically preferable limitations are attached thereto. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these forms.

[First Embodiment]
FIG. 1 is an overall view of a GPS system including an antenna built-in electronic timepiece 100 (hereinafter referred to as “electronic timepiece 100”) according to a first embodiment of the present invention. The electronic timepiece 100 is a wristwatch that receives radio waves (radio signals) from the GPS satellite 20 and corrects the internal time, and is a surface opposite to a surface (hereinafter referred to as “back surface”) that contacts the arm (hereinafter referred to as “surface”). ”).

  The GPS satellite 20 is a position information satellite that orbits a predetermined orbit over the earth, and transmits a navigation message superimposed on a 1.57542 GHz radio wave (L1 wave) to the ground. In the following description, the 1.57542 GHz radio wave on which the navigation message is superimposed is referred to as a “satellite signal”. The satellite signal is a right-handed circularly polarized wave.

  Currently, there are about 31 GPS satellites 20 (in FIG. 1, only 4 out of about 31 are shown), and in order to identify which GPS satellite 20 the satellite signal was transmitted from, The GPS satellite 20 superimposes a unique pattern of 1023 chips (1 ms period) called a C / A code (Coarse / Acquisition Code) on the satellite signal. The C / A code looks like a random pattern with each chip being either +1 or -1. Therefore, by correlating the satellite signal and the pattern of each C / A code, the C / A code superimposed on the satellite signal can be detected.

  The GPS satellite 20 is equipped with an atomic clock, and the satellite signal includes extremely accurate time information (hereinafter referred to as “GPS time information”) measured by the atomic clock. Further, a slight time error of the atomic clock mounted on each GPS satellite 20 is measured by a control segment on the ground, and the satellite signal includes a time correction parameter for correcting the time error. The electronic timepiece 100 receives a satellite signal transmitted from one GPS satellite 20, and corrects the internal time to an accurate time by using GPS time information and a time correction parameter included therein.

  The satellite signal includes orbit information indicating the position of the GPS satellite 20 on the orbit. The electronic timepiece 100 can perform positioning calculation using GPS time information and orbit information. The positioning calculation is performed on the assumption that the internal time of the electronic timepiece 100 includes some error. That is, in addition to the x, y, and z parameters for specifying the three-dimensional position of the electronic timepiece 100, the time error is also an unknown number. Therefore, the electronic timepiece 100 generally receives satellite signals respectively transmitted from four or more GPS satellites, and performs positioning calculation using GPS time information and orbit information included therein.

  FIG. 2 is a plan view of the electronic timepiece 100. As shown in FIG. 2, the electronic timepiece 100 includes a cylindrical outer case 80 formed of a nonconductive member such as ceramic or plastic. An annular bezel 81 formed of a non-conductive member such as the like is fitted. A disc-shaped dial plate 11 is arranged as a time display portion on the inner peripheral side of the bezel 81 via an annular dial ring 83 made of plastic. On the dial plate 11, the time and date are displayed. A pointer 13 (13a to 13c) for displaying and a liquid crystal display panel 14 are arranged. The opening on the surface side of the outer case 80 is closed with a cover glass 84 through a bezel 81, and the dial plate 11, the hands 13 (13 a to 13 c) and the liquid crystal display panel are connected through the cover glass 84. 14 is visible. In FIG. 2, the characters “TYO” displayed on the liquid crystal display panel 14 mean “Tokyo” and display the time of Japan in the world time function.

  The dial ring 83 has a horizontal annular portion in contact with the inner peripheral surface of the bezel 81 on the outer peripheral side, and a mortar-shaped portion whose inner peripheral side is inclined inward. A doughnut-shaped storage space 82 is defined by the mortar-shaped portion and the inner peripheral surface of the bezel 81. An annular antenna body 40 is stored in the storage space 82.

  The antenna body 40 functions as a loop antenna and is configured to be annularly arranged along the outer edge of the dial 11 serving as a time display unit. In this embodiment, the antenna body 40 is arranged around the dial 11, Two feeding electrodes 40 a and 40 b for the antenna body 40 are arranged on the dial 11 from 6 o'clock to 9 o'clock or from 12 o'clock to 3 o'clock. The pair of power supply electrodes 40 a and 40 b are electrodes that supply power to the antenna body 40.

  Further, the electronic timepiece 100 manually receives the satellite signal from at least one GPS satellite 20 and corrects the internal time information by manually operating the crown 16 and the operation buttons 17 and 18 shown in FIGS. A mode (time information acquisition mode) and a mode (position information acquisition mode) in which satellite signals from a plurality of GPS satellites 20 are received and positioning calculation is performed to correct the time difference of internal time information are configured. The electronic timepiece 100 can also execute the time information acquisition mode and the position information acquisition mode periodically (automatically).

  FIG. 3 is a partial cross-sectional view showing the internal structure of the electronic timepiece 100, and FIG. 4 is an exploded perspective view of a part of the electronic timepiece 100. As shown in FIGS. 3 and 4, in the electronic timepiece 100, an annular bezel 81 made of ceramic is fitted on the surface side of a cylindrical outer case 80 made of ceramic, and the bezel 81 A ring-shaped dial ring 83 made of plastic is attached along the inner periphery. Of the two openings of the exterior case 80, the opening on the front side is closed with a cover glass 84 via an annular bezel 81, and the opening on the back side is closed with a back cover 85 formed of metal. ing. The metal back cover 85 and the metal outer case 80 are fixed by screw grooves.

  The electronic timepiece 100 also includes a secondary battery 27 such as a lithium ion battery inside the outer case 80. The secondary battery 27 is charged with electric power generated by a solar panel 87 described later. That is, solar charging is performed. The electronic timepiece 100 includes a light-transmitting dial plate 11, a pointer shaft 12 penetrating the dial plate 11, and a plurality of hands 13 (circling around the pointer shaft 12 to indicate the current time. A second hand 13a, a minute hand 13b and an hour hand 13c), and a driving mechanism 30 for driving the plurality of hands 13 by rotating the pointer shaft 12. The pointer shaft 12 extends in the front and back direction along the central axis of the exterior case 80.

  The dial plate 11 is a circular plate member that constitutes a time display unit that displays the time inside the outer case 80, is formed of a light-transmitting material such as plastic, and has a pointer 13 (13a) between it and the cover glass 84. ˜c) are arranged inside the dial ring 83. A hole through which the pointer shaft 12 passes is formed at the center of the dial 11 and an opening for allowing the liquid crystal display panel 14 to be visually recognized is formed.

  The drive mechanism 30 is attached to the movement 38, has a step motor and a gear train such as a gear, and the step motor drives the plurality of hands 13 by rotating the hands 13 through the wheel train. Specifically, the hour hand 13c makes a full turn in 12 hours, the minute hand 13b in 60 minutes, and the second hand 13a in 60 seconds. The movement 38 to which the drive mechanism 30 is attached is arranged so that the dial 11 is sandwiched between the movement 13 and the pointer 13.

  The electronic timepiece 100 also includes a solar panel 87 that performs photovoltaic power generation inside the exterior case 80. The solar panel 87 is a circular flat plate in which a plurality of solar cells (photovoltaic elements) that convert light energy into electric energy (electric power) are connected in series. The solar panel 87 is disposed between the dial 11 and the drive mechanism 30 and has pointers. It extends along the cross section of the shaft 12. The solar panel 87 is disposed inside the dial ring 83 in the extending direction. In addition, a hole through which the pointer shaft 12 passes is formed at the center of the solar panel 87, and an opening for allowing the liquid crystal display panel 14 to be visually recognized is formed.

  The electronic timepiece 100 includes an antenna connection pins 44A and 44B, a circuit board 25, a balun 10 mounted on the circuit board 25, a GPS receiving unit (wireless receiving unit) 26, and a control unit 70 inside the exterior case 80. Is provided. The balun 10 is a balanced-unbalanced conversion element, and converts a balanced signal from the antenna body 40 that operates by balanced feeding into an unbalanced signal that can be handled by the GPS receiver 26.

The electronic timepiece 100 includes an annular antenna body 40. The antenna body 40 is formed by using a ring-shaped dielectric 40d as a base material and forming a metal antenna pattern 40c thereon by plating or silver paste printing. In the present embodiment, the antenna body 40 is disposed around the dial plate 11 and is accommodated on the inner peripheral surface side of the bezel 81, and the upper portion thereof is covered with a dial ring 83 and a cover glass 84. As this dielectric, a dielectric material that can be used at high frequencies, such as titanium oxide, can be formed by mixing it with a resin, and this makes it possible to further reduce the size of the antenna in combination with shortening the wavelength of the dielectric. The antenna pattern 40c functions as an antenna element that converts electromagnetic waves into current.
For example, in the case of GPS reception, since it is 1.575 GHz, one wavelength is 19 cm. In order to embed a normal antenna in a bezel portion of a wristwatch, it does not fit as it is, and the wavelength needs to be shortened. In the present embodiment, since the wavelength shortening by the dielectric becomes √εr, in the present embodiment, εr = about 5 to 10 is used as the dielectric 40d. Thereby, even if it is an antenna for GPS reception, a 1 wavelength loop antenna can be accommodated in a wristwatch, and size reduction of an antenna can be achieved.

  The antenna pattern 40c has a shape obtained by cutting out a part of a circle. The antenna body 40 is fed with power through two feed electrodes 40a and 40b located across the notch portion of the antenna pattern 40c. The pair of feed electrodes 40a and 40b has antenna connection pins 44A and 44B. The antenna connection pins 44A and 44B are pin-shaped connectors made of metal with a built-in spring. The antenna connection pins 44A and 44B protrude from the circuit board 25 and pass through the insertion holes 38a and 38b opened in the movement 38 so as to be stored. The circuit board 25 and the antenna body 40 in the storage space 82 are connected to each other.

  In the present embodiment, power supply to the antenna body 40 is balanced power supply from the balun 10 through the two power supply electrodes 40a and 40b. Specifically, the antenna body 40 includes positive and negative power supply electrodes 40a and 40b, and these two power supply electrodes 40a and 40b are connected to the antenna connection pins 44A and 44B. Balanced power feeding is performed via these antenna connection pins 44 </ b> A and 44 </ b> B, and the GPS receiver 26 receives a radio signal using the antenna body 40. Note that since the antenna body 40 is a one-wavelength loop antenna, it has a self-balancing action with respect to power feeding, and can be fed directly without the balun 10.

Further, a flange portion 40e is formed on the inner peripheral portion of the antenna body 40, and the flange portion 40e and a claw-shaped holding portion 90 formed integrally with the movement 38 are fitted as shown in FIG. It has come to be combined.
The movement 38 is composed of a plastic part and a metal part, and the claw-shaped holding part 90 is a plastic part formed by molding.
As described above, the antenna body 40 is held by the claw-shaped holding portion 90 formed integrally with the movement 38, so that the antenna circuit 40 is held in the movement 38 before assembling the exterior parts. Can be adjusted. After the adjustment with the receiving circuit is completed, it is possible to mount the movement 38 and the antenna body 40 and assemble the exterior parts.

  Further, since the position of the antenna body 40 is set on the lower surface of the cover glass 84, it is possible to ensure good reception. In addition, since the upper portion of the antenna body 40 is covered with the dial ring 83, the antenna body 40 is not exposed and can be designed on the dial ring 83. There is no reduction. And since the position of the antenna body 40 is set outside the dial 11, the design freedom of the dial 11 is not lowered.

Furthermore, since the antenna body 40 is securely held by the claw-shaped holding portion 90 of the movement 38, it is possible to prevent the antenna body 40 from being deformed even when an impact or the like occurs, and to reduce the reception performance. Can be prevented.
In the example shown in FIG. 4, the claw-shaped holding portions 90 are formed at three locations of the movement 38, but the present invention is not limited to this example, and the number may be increased.

  FIG. 5 is a block diagram showing a circuit configuration of the electronic timepiece 100. As shown in FIG. 5, the electronic timepiece 100 includes a GPS receiving unit 26 and a control display unit 36. The GPS receiver 26 performs processing such as satellite signal reception, GPS satellite 20 acquisition, position information generation, and time correction information generation. The control display unit 36 performs processing such as holding internal time information and correcting internal time information.

  The solar panel 87 charges the secondary battery 27 through the charge control circuit 29. The electronic timepiece 100 includes regulators 34 and 35, and the secondary battery 27 supplies drive power to the control display unit 36 via the regulator 34 and to the GPS reception unit 26 via the regulator 35. The electronic timepiece 100 also includes a voltage detection circuit 37 that detects the voltage of the secondary battery 27. Instead of the regulator 35, for example, a regulator 35-1 that supplies driving power to the RF unit 50 (details will be described later) and a regulator 35-2 that supplies driving power to the baseband unit 60 (details will be described later). Both of them may be provided separately. The regulator 35-1 may be provided inside the RF unit 50.

  The electronic timepiece 100 includes an antenna body 40, a balun 10, and a SAW (Surface Acoustic Wave) filter 32. As described in FIG. 1, the antenna body 40 receives satellite signals from the plurality of GPS satellites 20. However, since the antenna body 40 also receives some unnecessary radio waves other than the satellite signal, the SAW filter 32 performs a process of extracting the satellite signal from the signal received by the antenna body 40. That is, the SAW filter 32 is configured as a band-pass filter that passes a 1.5 GHz band signal.

  The GPS receiving unit 26 includes an RF (Radio Frequency) unit 50 and a baseband unit 60. As will be described below, the GPS receiver 26 performs a process of acquiring satellite information such as orbit information and GPS time information included in the navigation message from the 1.5 GHz band satellite signal extracted by the SAW filter 32.

  The RF unit 50 includes an LNA (Low Noise Amplifier) 51, a mixer 52, a VCO (Voltage Controlled Oscillator) 53, a PLL (Phase Locked Loop) circuit 54, an IF amplifier 55, an IF (Intermediate Frequency) filter 56, an ADC (ADC). (A / D converter) 57 and the like.

  The satellite signal extracted by the SAW filter 32 is amplified by the LNA 51. The satellite signal amplified by the LNA 51 is mixed with the clock signal output from the VCO 53 by the mixer 52 and down-converted to an intermediate frequency band signal. The PLL circuit 54 compares the phase of the clock signal obtained by dividing the output clock signal of the VCO 53 with the reference clock signal, and synchronizes the output clock signal of the VCO 53 with the reference clock signal. As a result, the VCO 53 can output a clock signal with a stable frequency accuracy of the reference clock signal. For example, several MHz can be selected as the intermediate frequency.

  The signal mixed by the mixer 52 is amplified by the IF amplifier 55. Here, by the mixing in the mixer 52, a high-frequency signal of several GHz is generated together with the signal in the intermediate frequency band. Therefore, the IF amplifier 55 amplifies a high frequency signal of several GHz along with the signal in the intermediate frequency band. The IF filter 56 passes the signal in the intermediate frequency band and removes the high frequency signal of several GHz (precisely, attenuates below a predetermined level). The intermediate frequency band signal that has passed through the IF filter 56 is converted into a digital signal by an ADC (A / D converter) 57.

  The baseband unit 60 includes a DSP (Digital Signal Processor) 61, a CPU (Central Processing Unit) 62, an SRAM (Static Random Access Memory) 63, and an RTC (Real Time Clock) 64. The baseband unit 60 is connected to a crystal oscillation circuit with temperature compensation circuit (TCXO: Temperature Compensated Crystal Oscillator) 65, a flash memory 66, and the like.

  A crystal oscillation circuit (TCXO) 65 with a temperature compensation circuit generates a reference clock signal having a substantially constant frequency regardless of the temperature. The flash memory 66 stores, for example, time difference information. The time difference information is information in which time difference data (such as a correction amount for UTC associated with coordinate values (for example, latitude and longitude)) is defined.

  When set to the time information acquisition mode or the position information acquisition mode, the baseband unit 60 performs a process of demodulating the baseband signal from the digital signal (intermediate frequency band signal) converted by the ADC 57 of the RF unit 50.

  In addition, when the time information acquisition mode or the position information acquisition mode is set, the baseband unit 60 generates a local code having the same pattern as each C / A code in the satellite search process described later, and generates a baseband signal. A process of correlating each C / A code included and the local code is performed. Then, the baseband unit 60 adjusts the local code generation timing so that the correlation value for each local code has a peak, and if the correlation value is equal to or greater than the threshold, it synchronizes with the GPS satellite 20 of that local code (that is, The GPS satellite 20 is captured). Here, the GPS system employs a CDMA (Code Division Multiple Access) method in which all GPS satellites 20 transmit satellite signals of the same frequency using different C / A codes. Therefore, by detecting the C / A code included in the received satellite signal, it is possible to search for a GPS satellite 20 that can be captured.

Further, the baseband unit 60 uses a local code having the same pattern as the C / A code of the GPS satellite 20 in order to acquire the satellite information of the captured GPS satellite 20 in the time information acquisition mode or the position information acquisition mode. Performs processing to mix baseband signals. In the mixed signal, a navigation message including satellite information of the captured GPS satellite 20 is demodulated. Then, the baseband unit 60 detects TLM words (preamble data) of each subframe of the navigation message, and acquires satellite information such as orbit information and GPS time information included in each subframe (for example, stored in the SRAM 63). ) Process. Here, the GPS time information is the week number data (WN) and the Z count data, but may be only the Z count data when the week number data has been acquired previously.
And the baseband part 60 produces | generates the time correction information required in order to correct internal time information based on satellite information.

  In the time information acquisition mode, more specifically, the baseband unit 60 performs time measurement calculation based on the GPS time information, and generates time correction information. The time correction information in the time information acquisition mode may be, for example, GPS time information itself or information on a time difference between the GPS time information and the internal time information.

On the other hand, in the position information acquisition mode, more specifically, the baseband unit 60 performs positioning calculation based on GPS time information and orbit information, and the position information (more specifically, the electronic timepiece 100 is Get the latitude and longitude of the location. Further, the baseband unit 60 refers to the time difference information stored in the flash memory 66 and acquires time difference data associated with the coordinate values (for example, latitude and longitude) of the electronic timepiece 100 specified by the position information. . In this way, the baseband unit 60 generates satellite time data (GPS time information) and time difference data as time correction information. As described above, the time correction information in the position information acquisition mode may be the GPS time information and the time difference data itself. For example, instead of the GPS time information, the time correction information is a time difference data between the internal time information and the GPS time information. Also good.
The baseband unit 60 may generate time correction information from the satellite information of one GPS satellite 20, or may generate time correction information from the satellite information of a plurality of GPS satellites 20.

  The operation of the baseband unit 60 is synchronized with the reference clock signal output from the crystal oscillation circuit with temperature compensation circuit (TCXO) 65. The RTC 64 generates timing for processing satellite signals. The RTC 64 is counted up by the reference clock signal output from the TCXO 65. The RTC 64 provided in the baseband unit 60 operates only during reception of the satellite information of the GPS satellite 20, and holds GPS time information.

The control display unit 36 includes a control unit 70, a drive circuit 74, and a crystal resonator 73.
The control unit 70 includes a storage unit 71 and an RTC (Real Time Clock) 72 and performs various controls. The control unit 70 can be configured by a CPU, for example.
The controller 70 sends a control signal to the GPS receiver 26 and controls the reception operation of the GPS receiver 26. Further, the control unit 70 controls the operation of the regulator 34 and the regulator 35 based on the detection result of the voltage detection circuit 37. The control unit 70 controls the driving of all the hands via the drive circuit 74.

  The storage unit 71 stores internal time information. The RTC 72 operates constantly, measures the internal time for time display, and generates internal time information. The internal time information is time information measured inside the electronic timepiece 100 and is updated by a reference clock signal generated by the crystal unit 73. Therefore, even if the power supply to the GPS receiver 26 is stopped, the internal time information can be updated and the hand movement of the pointer can be continued.

  When the time information acquisition mode is set, the control unit 70 controls the operation of the GPS receiving unit 26, corrects the internal time information based on the GPS time information, and stores the internal time information in the storage unit 71. More specifically, the internal time information is corrected to UTC (Coordinated Universal Time) obtained by adding a UTC offset to the acquired GPS time information. Further, when the position information acquisition mode is set, the control unit 70 controls the operation of the GPS receiving unit 26, corrects and stores the internal time information based on the satellite time data (GPS time information) and the time difference data. Store in the unit 71.

  As described above, in the electronic timepiece 100, the antenna body 40 is a C-shaped loop antenna as a whole, and the pair of feeding electrodes 40a and 40b serving as the start point and end point of the loop antenna sandwich the notch portion of the antenna pattern 40c. Will be located at. For this reason, by setting the distance from the feeding electrode 40a to the feeding electrode 40b of the antenna pattern 40c, that is, the peripheral length from the start point to the end point of the loop antenna to about one wavelength shortened by the dielectric 40d, a half-wave dipole is obtained. The reception performance equivalent to the case where two antennas are placed in parallel with the feeding electrodes 40a and 40b interposed therebetween can be maintained.

  In particular, in the electronic timepiece 100 according to the present embodiment, the radiation directivity is such that the direction in which the power supply electrodes 40a and 40b are seen from the center of the ring is the maximum radiation direction. By placing it in the 10 o'clock range or the 12 o'clock to 4 o'clock range, the direction in which the antenna gain is large when the wearer is in the posture of lowering the wrist arm or placing his hand in front of the body This coincides with the zenith direction, and reception performance is sufficiently exhibited.

  In detail, since satellite signals cannot be received indoors, reception is performed while wearing a wrist watch on the arm and outdoors, in which case the wearer is holding his arm down or holding his hand in front of the body. In many cases, the posture is positioned in the position. Therefore, as shown in FIGS. 6 and 7, the probability that the 6 o'clock to 10 o'clock position of the electronic timepiece 100 faces the zenith direction is high. In the electronic timepiece 100 according to the present embodiment, the antenna feeding position is from 6 o'clock to 10 o'clock, or from 12 o'clock to 4 o'clock where the same performance can be obtained. The probability that the larger direction is toward the zenith direction is higher.

  8-10 is explanatory drawing of the radiation pattern of the antenna body 40. FIG. FIG. 8 is an explanatory diagram showing a coordinate system centered on the antenna body 40. The center point of the circular antenna body 40 (radius a) is the origin, the horizontal plane including the watch surface is the XY plane, and the watch surface is shown. The normal line direction is taken as the Z axis, and the feeding electrodes 40a and 40b are installed on the X axis. The radiation pattern shown in FIG. 9 is a radiation pattern on the Y-X plane in which θ shown in FIG. 8 is set to 90 °, and the feeding electrodes 40a and 40b are positioned on the X axis near the origin. The radiation pattern shown in FIG. 10 is a radiation pattern in the ZX plane in which φ shown in FIG. 8 is set to 90 °, and the feeding electrodes 40a and 40b are located on the origin. In FIG. 10, the solid line is a radiation pattern with a back cover, and the wavy line is a radiation pattern with no back cover.

  As shown in FIG. 9, when feeding electrodes 40a and 40b are positioned on the X axis, the X axis direction is the maximum radiation direction and the antenna gain is maximum, the Y axis direction is the null value, and the antenna gain is low. It has become. Therefore, when the power supply electrodes 40a and 40b are positioned in the range of 6 o'clock to 10 o'clock or 12 o'clock to 4 o'clock as in the present invention, the wristwatch is worn on the wrist and reception is performed outdoors. The radiation directivity of the antenna body 40 can be maximized in a posture that a wearer takes many ergonomically.

  In FIG. 10, the antenna radiation patterns are compared with and without the metal back cover. It can be seen that if there is a metal back on the YZ plane, radiation in the dial direction (Z-axis) increases due to reflection, and desirable antenna characteristics can be obtained when the watch surface is directed to the apex. If the case is made of metal and is too close to the antenna, the antenna characteristics deteriorate, but in this embodiment, the outer case 80 is a non-conductive member, so there is no such influence. The back cover 85 is separated by the movement 38, the drive mechanism 30, and the like, and has an appropriate distance from the antenna body 40. Therefore, the back cover 85 can function effectively as a reflector without deteriorating antenna characteristics.

  In the electronic timepiece 100, the antenna can be reduced in size by utilizing the wavelength shortening by the dielectric 40d. That is, since the wavelength shortening due to the dielectric becomes √εr, in this embodiment, the dielectric 40d is about εr = 5 to 10, so that even a GPS receiving antenna can be used in a wristwatch. A one-wavelength loop antenna can be accommodated, and the antenna can be miniaturized. Further, since a ground plate is not required, there is an advantage that it is easy to use even in a small device that does not require a large size ground plate. In the present embodiment, the antenna body 40 has the antenna pattern 40c formed on the surface of the ring-shaped dielectric 40d by plating, silver paste printing, or the like. When the antenna pattern 40c is formed on the surface, it is easy to process and the frequency adjustment is also easy.

  Furthermore, since the antenna body 40 is balancedly fed through the feeding electrodes 40a and 40b, the feeding electrodes 40a and 40b can form a balanced antenna pattern 40c, and reception performance can be improved. Moreover, since the metal back cover that closes the opening on the opposite side to the display direction of the time display part among the two openings of the side surface part is provided, the normal direction on the watch surface is reflected by the reflection from the metal back cover. Radiation becomes larger, and extremely high reception performance can be obtained.

In addition, the antenna body 40 is held by the claw-shaped holding portion 90 formed integrally with the movement 38, so that the antenna body 40 is held by the movement 38 before assembling the exterior parts. Adjustment is possible, and the efficiency of the adjustment process and the assembly process can be improved.
The position of the antenna body 40 held by the movement 38 is set on the lower surface of the cover glass 84 to ensure good reception, and the upper portion of the antenna body 40 is covered with the dial ring 83 to expose the antenna body 40. And the design freedom is not reduced. Furthermore, since the antenna body 40 is securely held by the claw-shaped holding portion 90 of the movement 38, the antenna body 40 can be prevented from being deformed even when an impact or the like occurs, and the above-described good High reception performance can be maintained.

  As described above, according to the present invention, when receiving a satellite signal by GPS, it is possible to obtain a practically optimal antenna directivity based on ergonomics such as the posture of a wearer outdoors, and to reduce the size of the antenna. The reception performance can be maintained sufficiently high.

[Second Embodiment]
FIG. 11 is a plan view of an antenna built-in type electronic timepiece 200 (electronic timepiece 200) according to the second embodiment of the present invention, and FIG. 12 shows an antenna built-in type electronic timepiece 200 according to the second embodiment of the present invention. It is a partial sectional view of electronic timepiece 200). The electronic timepiece 200 is different from the electronic timepiece 100 in that an antenna body 42 is provided instead of the antenna body 40. The antenna body 42 is different from the antenna body 40 in that the antenna body 42 is a spiral ring antenna in which a spiral body formed by winding a wire rod in a coil shape is annularly arranged along the outer edge of the dial 11 serving as a time display unit.

  The antenna body 42 is a spiral ring antenna in which a spiral body formed by winding a wire rod in a coil shape is annularly arranged along the outer edge of the dial plate 11 that is a time display unit. 11, and two feeding electrodes 42 a and 42 b for the antenna body 42 are arranged on the dial 11 from 6 o'clock to 9 o'clock or from 12 o'clock to 3 o'clock. The feed electrodes 42 a and 42 b are electrodes that feed the antenna body 42 at the start and end points of the spiral portion of the antenna body 42.

  The antenna body 42 is basically a shortened antenna of a one-wavelength loop antenna. In this embodiment, the antenna body 42 is accommodated on the inner peripheral surface side of the bezel 81 and is covered with a dial ring 83 and a cover glass 84. . As the antenna body 42, the resonance frequency can be set to 1 / 1.5 to 1 / 1.7 of a normal one-wavelength loop antenna. As the antenna body 42, in order to maintain the coil shape, a dielectric made of a ring-shaped resin molding may be arranged as a core of the coil, and a wire or a plate may be wound around the dielectric. . As this dielectric, a dielectric material that can be used at high frequencies, such as titanium oxide, can be formed by mixing it with a resin, and this makes it possible to further reduce the size of the antenna in combination with shortening the wavelength of the dielectric.

  The antenna body 42 is fed with power through two feeding electrodes 42a and 42b located at the start and end points of the line antenna constituting the coil. The pair of feed electrodes 42a and 42b are connected to antenna connection pins 44A and 44B arranged on the lower surface of the antenna. The antenna connection pins 44A and 44B are pin-shaped connectors made of metal with a built-in spring. The antenna connection pins 44A and 44B protrude from the circuit board 25 and pass through the insertion holes 38a and 38b opened in the movement 38 so as to be stored. The circuit board 25 and the antenna body 42 in the storage space 82 are connected to each other.

  In the present embodiment, the power supply to the antenna body 42 is balanced power supply from the balun 10 through the two power supply electrodes 42a and 42b. Specifically, the feeding electrodes 42a and 42b of the antenna body 42 are connected to the antenna connection pins 44A and 44B. Balanced feeding is performed via these antenna connection pins 44A and 44B, and the GPS receiver 26 receives a radio signal using the antenna body 42. Note that since the antenna body 40 is a one-wavelength loop antenna, it has a self-balancing action with respect to power feeding, and can be fed directly without the balun 10.

  Further, in the electronic timepiece 300, the antenna can be miniaturized by making the antenna into a coil shape. For example, in the case of a GPS satellite signal, since the frequency is 1.575 GHz, one wavelength is 19 cm, but the circumference can be 12 cm by making it into a coil shape, so the diameter can be 3.8 cm and the watch size. it can. The antenna body 42 according to the present embodiment has a loop circumference of about one wavelength, can obtain reception performance equivalent to the case where two half-wave dipole antennas are arranged in parallel, and does not require a ground plate. Therefore, there is an advantage that it is easy to use even with a small device.

  Furthermore, since the antenna body 42 is balancedly fed through the feeding electrodes 42a and 42b, the feeding electrodes 42a and 42b can form a balanced antenna pattern, and reception performance can be improved. Moreover, since the metal back cover that closes the opening on the opposite side to the display direction of the time display part among the two openings of the side surface part is provided, the normal direction on the watch surface is reflected by the reflection from the metal back cover. Radiation becomes larger, and extremely high reception performance can be obtained.

In the present embodiment, the antenna body 42 is sandwiched by a pair of claw-shaped holding portions 91 a and 91 b that are formed integrally with the movement 38.
The pair of claw-shaped holding portions 91 a and 91 b may be provided at a plurality of locations in the circumferential direction of the movement 38. For example, it can be considered to be provided at three places as in the first embodiment. However, the number is not limited to three. Further, the circumferential width of the pair of nail-shaped holding portions 91a and 91b may be set as appropriate.

Since the present embodiment includes the pair of claw-shaped holding portions 91a and 91b as described above, even when the spiral ring antenna as described above is used as the antenna body 42, the antenna body is required before assembling the exterior parts. The receiving circuit can be adjusted in a state where 42 is held by the movement 38, and the efficiency of the assembly and adjustment process can be improved.
Further, by setting the position of the antenna body 42 held by the movement 38 on the lower surface of the cover glass 84, good reception is ensured, and the upper portion of the antenna body 42 is covered by the dial ring 83, thereby the antenna body 42. This prevents exposure of the camera and reduces the degree of freedom in design. Furthermore, since the antenna body 42 is securely held by the pair of claw-like holding portions 91a and 91b of the movement 38, the antenna body 42 can be prevented from being deformed even when an impact or the like occurs. Thus, it is possible to maintain good reception performance.

[Third Embodiment]
FIG. 13 is a partial cross-sectional view of an antenna built-in type electronic timepiece 300 (electronic timepiece 300) according to the third embodiment of the present invention. The electronic timepiece 300 is different from the electronic timepiece 200 in that an antenna body 43 is provided instead of the antenna body 42. The antenna body 43 is different from the antenna body 42 in that the antenna body 43 includes an annular dielectric body 43d, and the spiral body portion 43c of the spiral ring antenna is configured to be in contact with the dielectric body 43d.

  Specifically, as shown in FIG. 13, in this embodiment, in the storage space 82 defined in a donut shape by the dial ring 83 and the inner peripheral surface of the bezel 81, it extends in the circumferential direction. The antenna body 43 is configured by winding a spiral ring portion 43c of a spiral ring antenna around the dielectric 43d as a winding core.

  The dielectric 43d is a dielectric such as a dielectric ceramic, but may be formed by insert molding using a plastic mixed with a dielectric. In the present embodiment, the winding cross section of the antenna body 43 described above is substantially square. The dielectric 43d and the spiral portion 43c are covered with a dial ring 83 as viewed from the front side.

  In the third embodiment, the exterior case 80 is made of metal, and the exterior case 80 and the metal back cover 85 are made to function as a ground plate. That is, one power supply electrode (not shown) of the antenna body 43 is connected to the metal outer case 80 via the conduction spring 38c. The other power feeding electrode (not shown) is fed through the antenna connection pin 44. At this time, since the antenna body 43 is a one-wavelength loop antenna, it has a self-balancing action with respect to power feeding, and can be fed directly without using the balun 10.

  As is clear from the above description, according to the electronic timepiece 300, the same effect as the electronic timepiece 200 can be obtained. As a further effect, the antenna perimeter can be shortened in combination with the wavelength shortening effect of the dielectric 43d, whereby the entire antenna can be further downsized. Further, by contacting with the dielectric 43d, the winding pitch of the spiral 43c can be fixed so as not to move, and the stability of the apparatus can be improved. Further, by making the winding cross section of the antenna body 43 substantially square, there is no useless space, the space in the timepiece can be used effectively, and the size can be reduced.

  In the present embodiment, one of the feeding electrodes of the loop antenna is caused to function as the ground plate by using the exterior case 80 via the conductive spring 38c, so that the antenna connecting pin 44 can be made one, and the structure is simplified. Cost reduction can be achieved, and the degree of freedom of the position where the pair of power supply electrodes are arranged can be increased. Further, the size reduction can be promoted by omitting the balun 10 due to the self-balancing action with respect to the feeding of the antenna body 43.

Also in the present embodiment, the antenna body 43 is sandwiched by a pair of claw-shaped holding portions 91 a and 91 b that are formed integrally with the movement 38.
The pair of claw-shaped holding portions 91 a and 91 b may be provided at a plurality of locations in the circumferential direction of the movement 38. For example, it can be considered to be provided at three places as in the first embodiment. However, the number is not limited to three. Further, the circumferential width of the pair of nail-shaped holding portions 91a and 91b may be set as appropriate.

Since the present embodiment includes the pair of claw-shaped holding portions 91a and 91b as described above, even when the spiral ring antenna as described above is used as the antenna body 43, the antenna body is assembled before assembling the exterior parts. The receiving circuit can be adjusted while 43 is held in the movement 38, and the efficiency of the assembly / adjustment process can be improved.
Further, by setting the position of the antenna body 43 held by the movement 38 on the lower surface of the cover glass 84, good reception is ensured, and the upper portion of the antenna body 43 is covered with the dial ring 83 so that the antenna body 43 is covered. This prevents exposure of the camera and reduces the degree of freedom in design. Furthermore, since the antenna body 43 is securely held by the pair of claw-shaped holding portions 91a and 91b of the movement 38, the antenna body 43 can be prevented from being deformed even when an impact or the like occurs. Thus, it is possible to maintain good reception performance.

  In each of the above-described embodiments, the example in which the shape of the holding portion of the antenna body is a nail shape has been described. However, the present invention is not limited to such a shape, and the antenna body can be reliably held. Any other shape may be used.

100, 200, 300 ... Electronic clock with built-in antenna, 40, 42, 43 ... Antenna body, 40a, 40b, 42a, 42b, 43a, 43b ... Feed electrode, 40c, 43c ... Antenna pattern, 40d, 43d ... Dielectric, 44A, 44B ... Antenna connection pin, 11 ... Dial, 12 ... Pointer shaft, 13 (13a, 13b, 13c) ... Pointer, 26 ... GPS receiver, 30 ... Drive mechanism, 80 ... Exterior case, 81 ... Bezel, 82 ... Storage space, 83 ... Movement, 84 ... Cover glass, 85 ... Back cover, 87 ... Solar panel, 90, 91a, 91b ... Holding part.

Claims (7)

A cylindrical outer case at least partially formed of a non-conductive member;
A movement that is housed in the exterior case and includes a drive mechanism;
A time display unit arranged on the movement and displaying the time inside the exterior case;
Housed in the exterior case, and an annular antenna body;
A pair of feeding electrodes for feeding power to the antenna body,
The antenna body is disposed along an outer edge of the time display unit,
The movement includes a holding unit that holds the antenna body at a plurality of locations along an outer edge of the time display unit.
An electronic timepiece with a built-in antenna.   The electronic timepiece with built-in antenna according to claim 1, wherein the holding portion is formed integrally with the movement.   The antenna built-in type electronic timepiece according to claim 1, wherein the antenna body and the holding unit are arranged around the time display unit.   4. The electronic timepiece with built-in antenna according to claim 1, wherein the holding portion includes a claw-like portion that holds the antenna body. 5.   5. The antenna built-in type electronic timepiece according to claim 1, further comprising an annular cover member that covers the antenna body and the holding portion.   The said antenna body is provided with the flange part in the cyclic | annular inner peripheral part, The said holding | maintenance part hold | maintains the said antenna body by engaging with the said flange part. The electronic watch with a built-in antenna according to any one of the above items. 2. The antenna body according to claim 1, wherein the antenna body has a spiral shape formed by winding a wire rod in a coil shape, and the holding portions are a pair of holding portions that sandwich the spiral-shaped antenna body. The antenna built-in type electronic timepiece of any one of thru | or 5.

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