Abstract:
An antenna is positioned relative to one or more other components within a metal or alloy case member/back cover assembly of an electronic timepiece having a radio communication function to facilitate reception of radio waves by the antenna, and/or to reduce negative effects on the signal reception ability of the antenna caused by one or more other components. Thus positioning the antenna improves its reception, while the external appearance of the timepiece can be maintained or enhanced by using metal or alloy for the case member/back cover assembly.

Description:
CONTINUING APPLICATION DATA  
       [0001]     This application is a continuation of, and claims priority under 35 U.S.C. § 120 to U.S. application Ser. No. 10/840,574, filed May 6, 2004, the content of which is incorporated by reference herein in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates an electronic timepiece with a radio communication function such as a radio-controlled timepiece, and relates more particularly to an electronic timepiece with a radio communication function having an antenna positioned within the timepiece relative to one or more other components to facilitate reception of radio waves by the antenna.  
         [0004]     2. Description of the Related Art  
         [0005]     Radio-controlled timepieces having an antenna to receive a radio signal containing standard time information and adjust the time based on the received time signal are one type of electronic timepiece with a radio communication function for receiving radio frequency (RF) signals from external sources and transmitting RF signals to external devices. Radio-controlled timepieces that have the antenna disposed externally to the case so that the antenna can easily receive RF signals have been proposed (see, for example, Japanese Unexamined Patent Appl. Pub. H11-223684, FIG. 4). This radio-controlled timepiece can receive RF signals with good reception by means of the antenna even if the case member is metal without the metal case interfering with RF signal reception. However, locating the antenna externally to the case detracts from the appearance of the radio-controlled timepiece.  
         [0006]     Some radio-controlled timepieces also have solar power generating means, thermal power generating means, or other electrical generating means assembled with the movement of the timepiece, and use the generated output of such generating means to drive the timepiece (see, for example, Japanese Unexamined Patent Appl. Pub. 2003-121569, FIG. 1). However, while the antenna is disposed in the movement and the arrangement of the generating means and antenna are shown in the figures for the radio-controlled timepiece of this patent application, the location of the movement relative to the case is not described. As a result, there could be interference with signal reception by the antenna if, for example, the case is metal, and poor signal reception could result in some situations.  
         [0007]     Radio-controlled timepieces having the antenna housed inside the case have also been proposed (see, for example, Japanese Unexamined Patent Appl. Pub. 2002-31690, FIG. 6). The solar cell circuit board in this radio-controlled timepiece is located inside the movement at a position covering the antenna. However, because the solar cell circuit board is usually made from stainless steel or other metal, the circuit board can interfere with signal reception.  
         [0008]     A radio-controlled timepiece in which the dial is made from ceramic or other non-metallic material has also been proposed (see, for example, Japanese Unexamined Patent Appl. Pub. 2003-139869, FIG. 1). The back cover or case member of this radio-controlled timepiece, however, must be made from ceramic in order to lower the possibility of interference with signal reception, thus detracting from the appearance of the radio-controlled timepiece. If the back cover or case member is made of metal in order to improve the appearance, signals cannot be received with good reception because the antenna is surrounded by the back cover and case member.  
       SUMMARY OF THE INVENTION  
       [0009]     An object of the present invention is therefore to provide an electronic timepiece having a metal or alloy case member/back cover assembly and a radio communication function that includes an antenna positioned within the assembly relative to one or more other components to facilitate radio signal reception.  
         [0010]     According to one aspect of the invention, an electronic timepiece having a radio communication function is provided. Such electronic timepiece comprises a case member, and a back cover integrated with, or attached to, the case member, the case member and the back cover made of metal or alloy, the case member with which the back cover has been integrated or to which the back cover has been attached defining an interior and having an open end; an antenna housed in the interior; a time display unit configured to display the time and housed in the interior; and a movement housed in the interior, the movement including an electromagnetic motor configured to drive the time display unit. Moreover, with respect to an axial direction extending between the open end and the back cover, a distance between a center of the antenna and the open end is less than a distance between a center of the electromagnetic motor and the open end.  
         [0011]     The center of the antenna is preferably the center of the antenna core, in which case the core is made of metal or alloy. Alternatively, or additionally, the center of the electromagnetic motor is preferably the center of a coil of the electromagnetic motor.  
         [0012]     With respect to axial direction extending between the open end and the back cover, (i) a distance between the center of the antenna and the time display unit is less than a distance between a center of the movement and the time display unit, (ii) a distance between the center of the electromagnetic motor and the back cover is less than a distance between a center of the movement and the back cover, and/or (iii) a center of the movement is positioned between the center of the antenna and the center of the electromagnetic motor.  
         [0013]     In one embodiment, the time display unit includes a dial made of a nonconductive and nonmagnetic material. In such embodiment, the electronic timepiece described above preferably further comprises a photoelectric generator that is disposed on, or proximally to, a side of the dial facing in a direction of the back cover.  
         [0014]     In another aspect of the invention, an electronic timepiece having a radio communication function comprises a case member, and a back cover integrated with, or attached to, the case member, the case member and the back cover made of metal or alloy, the case member with which the back cover has been integrated or to which the back cover has been attached defining an interior and having an open end; an antenna housed in the interior, the antenna including a core made of high permeability material and a coil; and a time display unit configured to display the time and housed in the interior. With respect to an axial direction extending between the open end and the back cover, a distance between a center point of at least one continuous end surface segment of the core of the antenna and the time display unit is less than a distance between a center of the coil and a time display unit.  
         [0015]     In one embodiment, the coil of the antenna is wound around the core and at least one end of the antenna is bent toward the time display unit.  
         [0016]     In one embodiment, the time display unit includes a dial made of a nonconductive and nonmagnetic material. In such embodiment, the electronic timepiece described above preferably further comprises a photoelectric generator that is disposed on, or proximally to, a side of the dial facing in a direction of the back cover.  
         [0017]     In one embodiment, the electronic timepiece described above includes a movement housed in the interior, the movement including an electromagnetic motor configured to drive the time display unit. In such embodiment, with respect to axial direction extending between the open end and the back cover, a distance between the center of the antenna and the time display unit is less than a distance between a center of the electromagnetic motor and the time display unit.  
         [0018]     In another aspect of the invention, an electronic timepiece having a radio communication function comprises a case member, and a back cover integrated with, or attached to, the case member, the case member and the back cover made of metal or alloy, the case member with which the back cover has been integrated or to which the back cover has been attached defining an interior and having an open end; an antenna housed in the interior; a photoelectric generator disposed in the interior, the photoelectric generator having a support substrate made of a nonconductive and nonmagnetic material and a photoelectric conversion element that is supported on, or proximally to, the support substrate to receive light, the photoelectric conversion element being configured to generate electricity from the received light; a time display unit configured to display the time; and a drive unit configured to drive the time display unit using electricity generated by the photoelectric generator. The antenna is disposed on or under the photoelectric generator or proximally thereto between the photoelectric generator and the back cover, with an axis of the antenna being substantially parallel to the plane of the support substrate, such that the antenna is in a position overlapping the support substrate as seen in a plan view of the electronic timepiece.  
         [0019]     In still another aspect of the invention, an electronic an electronic timepiece having a radio communication function comprises a case member, and a back cover integrated with, or attached to, the case member, the case member and the back cover made of metal or alloy, the case member with which the back cover has been integrated or to which the back cover has been attached defining an interior and having an open end; an antenna housed in the interior, the antenna having two ends; a photoelectric generator disposed in the interior, the photoelectric generator having a support substrate and a photoelectric conversion element that is supported on, or proximally to, the support substrate to receive light, the photoelectric conversion element being configured to generate electricity from the received light; a time display unit configured to display the time; and a drive unit configured to drive the time display unit using electricity generated by the photoelectric generator. The antenna is disposed on or under the photoelectric generator or proximally thereto between the photoelectric generator and the back cover, with an axis of the antenna being substantially parallel to the plane of the support substrate, with at least both ends of the antenna in positions not overlapping the support substrate as seen in a plan view of the electronic timepiece.  
         [0020]     One or more of the following additional features may be embodied in either of the above-described aspects: the antenna is disposed between the photoelectric generator and the back cover at a specified distance from the photoelectric generator; the antenna and the photoelectric generator are disposed such that at least portions thereof overlap as seen in a side view of the electronic timepiece; a dial of the time display unit is disposed between the photoelectric generator and a cover member that covers the open end of the case member, in which case both the cover member and the dial are made of a nonconductive and nonmagnetic material; no other component of the electronic timepiece is disposed between the antenna and the photoelectric generator as seen in a side view of the electronic timepiece; no other component of the electronic timepiece is disposed between the antenna and a dial of the time display unit as seen in a side view of the electronic time piece; at least one other component of the electronic timepiece is disposed between the antenna and the back cover as seen in a side view of the electronic timepiece; a center of a core of the antenna is positioned on the open end side of a center of the movement in a height direction extending between the open end and the back cover; and/or a date wheel made of a nonconductive and nonmagnetic material is provided, which has a back cover side that faces in the direction of the back cover, in which case the antenna is disposed proximally to the back cover side between the back cover side and the back cover and overlaps the date wheel as seen in a plan view of the electronic timepiece.  
         [0021]     In any of the above-described aspects and embodiments thereof, the outer surface of the case member and/or the back cover preferably comprises molded synthetic resin that is coated with a thin film that is metallic or has metallic properties. Such construction further improves the appearance of the electronic timepiece with radio communication function.  
         [0022]     As the above descriptions indicate, the invention provides various arrangements for positioning the antenna relative to one or more other components within a metal or alloy case member/back cover assembly of the electronic timepiece to facilitate reception of radio waves by the antenna, and/or to reduce negative effects on the signal reception ability of the antenna caused by one or more other components. Thus positioning the antenna improves its reception, while the external appearance of the timepiece can be maintained or enhanced by using metal or alloy for the case member/back cover assembly.  
         [0023]     In embodiments having a support substrate made of nonconductive and nonmagnetic material, a radio signal, e.g., the standard time signal can travel through without interference from the support substrate. The antenna can therefore send and receive radio signals even when the support substrate is disposed between the antenna and the incoming radio signals. Being able to more freely position the antenna inside the case member while still maintaining good transmission and reception performance, enables improvements to the external appearance of the electronic timepiece to be made without sacrificing performance. For example, the back cover and case member can be made of metal.  
         [0024]     In some embodiments, the antenna is positioned so that it does not interfere with light reception by the photoelectric conversion unit from the open end of the case member, thereby preventing a drop in photoelectric conversion efficiency. In some arrangements, the photoelectric conversion unit can occupy a relatively large area inside the case member, also preventing a drop in photoelectric conversion efficiency.  
         [0025]     In one embodiment, no other component of the electronic timepiece with a radio communication function is disposed between the antenna and the photoelectric generator as seen in a side view of the electronic timepiece. With such an arrangement, the antenna can be easily located in closer proximity to the photoelectric generator.  
         [0026]     In one embodiment, one or more other components of the electronic timepiece with a radio communication function are disposed between the antenna and back cover as seen in a side view of the electronic timepiece. Preferably, the antenna and such other component(s) are located in overlapping positions as seen in a plan view of the electronic timepiece with a radio communication function. In such an arrangement, the antenna can be more easily disposed further from the back cover and thus closer to the open end of the case member. Radio communication with good, reliable reception by the antenna is thus possible through the open end. Note that these other components include, for example, the gears in the gear train for driving the hands, and a switch for driving the gear train manually, when the electronic timepiece with a radio communication function is an analog watch with hands.  
         [0027]     Rendering the antenna with its axis substantially parallel to the plane of the support substrate means herein that the angle between the direction of the antenna axis and the plane of the support substrate is greater than or equal to 0° and less than or equal to 30°, and is preferably less than or equal to 15°, and even further preferably less than or equal to 10°.  
         [0028]     A plan view of the electronic timepiece means viewing the electronic timepiece from the direction parallel to the axial direction of the case member. A side view of the electronic timepiece means viewing the electronic timepiece with a radio communication function from a direction perpendicular to the axial direction of the case member.  
         [0029]     Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]     In the drawings like reference symbols refer to like parts.  
         [0031]      FIG. 1  is a plan view of a radio-controlled timepiece according to a first embodiment of the present invention.  
         [0032]      FIG. 2  is a section view through line II-II in  FIG. 1 .  
         [0033]      FIG. 3  is a section view through line III-III in  FIG. 1 .  
         [0034]      FIG. 4  is a function block diagram of a radio-controlled timepiece according to this first embodiment of the present invention.  
         [0035]      FIG. 5  is a plan view of a radio-controlled timepiece according to a second embodiment of the present invention.  
         [0036]      FIG. 6  is a section view through line VI-VI in  FIG. 5 .  
         [0037]      FIG. 7  is a plan view of a radio-controlled timepiece according to a third embodiment of the present invention.  
         [0038]      FIG. 8  is a partial section view through line VIII-VIII in  FIG. 7 .  
         [0039]      FIG. 9  is a plan view of a radio-controlled timepiece according to the present invention showing a variation of the photoelectric generating means.  
         [0040]      FIG. 10  is a plan view showing a variation of a radio-controlled timepiece according to the present invention.  
         [0041]      FIG. 11  is a section view through line XI-XI in  FIG. 10 .  
         [0042]      FIG. 12  is a plan view showing another variation of a radio-controlled timepiece according to the present invention.  
         [0043]      FIG. 13  is a section view through line XIII-XIII in  FIG. 12 .  
         [0044]      FIG. 14  is a plan viewing showing a variation of the antenna location according to the present invention.  
         [0045]      FIG. 15  is a section view through line XV-XV in  FIG. 14 .  
         [0046]      FIG. 16  is a side section view showing a variation of the structure for affixing the antenna in the present invention.  
         [0047]      FIG. 17  is a partial side section view showing a variation of the structure for affixing the antenna in the present invention.  
         [0048]      FIG. 18  is a partial side section view showing a variation of the structure for affixing the antenna in the present invention.  
         [0049]      FIG. 19  is a partial side section view showing another variation of the structure for affixing the antenna in the present invention.  
         [0050]      FIG. 20  is a plan view showing a variation of the arrangement of the antenna and photoelectric generating means of the present invention.  
         [0051]      FIG. 21  is a partial side section view of  FIG. 20 .  
         [0052]      FIG. 22  is a plan view showing a variation of the shape of the antenna according to the present invention.  
         [0053]      FIG. 23  is a plan view showing another variation of the antenna arrangement according to the present invention.  
         [0054]      FIG. 24  is a partial side section view of  FIG. 23 .  
         [0055]      FIG. 25  shows a variation of an electronic timepiece with a radio communication function according to the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0056]     Preferred embodiments of the present invention are described below with reference to the accompanying figures. Note that parts in the second and subsequent embodiments that are identical to or have the same function as corresponding parts in the first embodiment are identified by the same reference numeral, and further description thereof is simplified or omitted.  
       First Embodiment  
       [0057]      FIG. 1  is a plan view of a radio-controlled timepiece  100  as an electronic timepiece with a radio communication function according to a first embodiment of the present invention,  FIG. 2  is a section view through line II-II in  FIG. 1 , and  FIG. 3  is a section view through line III-III in  FIG. 1 .  
         [0058]     This radio-controlled timepiece  100  is a wristwatch, and as shown in  FIG. 1 ,  FIG. 2 , and  FIG. 3  has a ring-shaped (a short cylindrical shape of which both ends are open) case member  1 .  
         [0059]     The case member  1  is a ring-shaped member of which both ends along the cylindrical axis L 1  are open, cylindrical axis L 1  being the axial direction of the gears that drive the hands (such as the axial direction of second wheel  444 ), and is made from metal such as brass, stainless steel, or titanium alloy. The thickness of the case member  1  is less than the diameter of the ring, and is preferably 10 mm or less or 5 mm or less. Lugs  11 ,  12  for attaching a wristwatch band are formed at mutually opposite positions on the outside circumference of the case member  1 . As viewed from the center of the case member  1 , the direction in which one of the lugs  11 ,  12  is rendered is the 12:00 direction, and the direction in which the other of the lugs  11 ,  12  is rendered is the 6:00 direction. In  FIG. 1 , the top of the figure (the side at lugs  11 ) is the 12:00 direction, and the bottom (the side at lugs  12 ) is the 6:00 direction.  
         [0060]     A stem  131  is disposed passing through the body of the case member  1  at approximately the 4:00 position. One end of the stem  131  is on the outside of the case member  1 , and a crown  132  is disposed to this end. The other end of the stem  131  is inside the case member  1 , and the yoke  133  and setting lever  134  are rendered to this end. The yoke  133  engages the clutch wheel  135  so that pulling the stem  131  out causes the clutch wheel  135  to move in the axial direction of the stem  131  by way of the intervening setting lever  134  and yoke  133 , engaging the day wheel (not shown) so that the positions of the hands can be adjusted. A switching unit  13  enabling the positions of the hands to be manually adjusted from outside the case is formed by, for example, the stem  131 , yoke  133 , setting lever  134 , and clutch wheel  135 .  
         [0061]     As shown in  FIG. 2  and  FIG. 3 , a time display means  2  is disposed on the side of one opening in the case member  1 , and a back cover (cover member)  3  closing the opening is disposed to the other opening (end portion) of the case member  1 . The top as seen in  FIG. 2  and  FIG. 3  is the top of the radio-controlled timepiece  100 , and the bottom as seen in the figures is the bottom of the radio-controlled timepiece  100 . In addition, the direction along the cylindrical axis L 1  is the thickness direction (height direction) of the radio-controlled timepiece  100 .  
         [0062]     The time display means  2  includes a dial  21  having a time display face  211  substantially perpendicular to the cylindrical axis L 1  (perpendicular to the surface of the paper in  FIG. 1 ) of the case member  1 , and hands  221 ,  222  that rotate above the dial  21 .  
         [0063]     The dial  21  is substantially disc-shaped with an area large enough to cover the opening in the case member  1 . The dial  21  is made from a nonconductive, nonmagnetic, optically transparent material such as inorganic glass, plastic, ceramic, paper, or other desirable material. The time display face  211  is rendered facing outward so that the face can be seen from the outside, and numbers, letters, or other indications (not shown) for representing the time are printed in a ring around the outside edge of the time display face  211 .  
         [0064]     The hands include the minute hand  221  for indicating the minute, and the hour hand  222  for indicating the hour. Both hands  221 ,  222  are made of bronze, aluminum, stainless steel, or other metal. The minute hands  221  and  22  rotate over the time display face  211  around substantially the center of the dial  21  as the axis of rotation, and indicate the time by pointing to the numbers, letters, or other markings on the time display face  211 . The hands are thus a 12-hour analog time display means representing a twelve hour period with one revolution of the hour hand  222 .  
         [0065]     A crystal (cover member)  23  is further disposed opposite the dial  21  with the hands  221 ,  222  therebetween. The crystal  23  is disposed covering one opening in the case member  1 , and the area of the crystal  23  is sufficient to cover this opening. The crystal  23  is made from a nonconductive, nonmagnetic, optically transparent material such as inorganic glass or organic glass.  
         [0066]     A photoelectric generating means  6  is disposed on the crystal  23  side (that is, on the side of one opening) of the case member  1  on the opposite side as the time display face  211  of the dial  21 . The photoelectric generating means  6  includes a photoelectric conversion element (photoelectric conversion unit)  61  for producing electricity by photoelectric conversion, and a support substrate  62  for supporting the photoelectric conversion element  61 .  
         [0067]     The photoelectric conversion element  61  is a substantially circular panel with substantially the same area as the dial  21 , and is made by building sequentially in order from the dial  21  side a transparent electrode layer (TOC), a semiconductor layer, and another transparent electrode layer (not shown). The transparent electrode layer has a transparent conductor film made of, for example, SnO2, ZnO, or ITO (indium tin oxide). The semiconductor layer is a PIN photodiode made of microcrystalline or amorphous silicon with a pn junction design. A reflective metal coating can be deposited on the transparent electrode layer on the side opposite from the dial  21 .  
         [0068]     The support substrate  62  is made from polyimide, glass-impregnated epoxy, ceramic, or other nonmagnetic, nonconductive material. The support substrate  62  is a flat member with substantially the same area as the photoelectric conversion element  61 , and is bonded to the photoelectric conversion element  61  on the opposite side as the dial  21 .  
         [0069]     The photoelectric generating means  6  is secured by bonding the photoelectric conversion element  61  to the dial  21 .  
         [0070]     The back cover  3  is disposed covering the other open end of the case member  1  opposite the dial  21  with a specific distance therebetween, and the area of the back cover  3  is sufficient to close this opening. The back cover  3  is made from a conductive, nonmagnetic metal such as stainless steel, bronze, or titanium alloy, or a conductive, magnetic metal such as permalloy.  
         [0071]     A movement  4  with a timekeeping function, a plastic spacer  14  for holding the movement  4  inside the case member  1 , a battery  49  for supplying power to the movement  4 , and an antenna  5  for receiving a standard time signal, are disposed inside the case member  1  between the dial  21  and back cover  3 .  
         [0072]     The movement  4  includes quartz oscillator unit  41  including a quartz oscillator  411  (see  FIG. 4 ), a circuit block (control block)  42  with a control function, drive means including stepping motors (electromagnetic motor)  43 A,  43 B for rotationally moving the hands  221 ,  222 , a gear train  44  for conveying the drive power of the stepping motors  43 A,  43 B as rotational movement to the hands  221 ,  222 , and a main plate  46  and gear train holder  47  for holding the gear train  44  therebetween in the cylindrical axis L 1  direction of the case member  1 .  
         [0073]     The quartz oscillator unit  41  has a quartz oscillator  411  for generating a reference clock. A 60-kHz quartz oscillator  412  and a 40-kHz quartz oscillator  413  are also provided as quartz oscillators for generating tuning signals for tuning to the frequency of the standard radio signal (60 kHz and 40 kHz). These quartz oscillators  412 ,  413  for generating tuning signals are disposed substantially in the direction of 9:00.  
         [0074]     The quartz oscillator unit  41  and circuit block  42  are disposed substantially in the direction of 12:00.  FIG. 4  is a function block diagram of the circuit block  42 .  
         [0075]     The circuit block  42  includes a reception circuit  421  for processing the standard radio signal received by the antenna  5  and outputting time information; a storage circuit  422  for storing the time information output by the reception circuit  421 ; a central control circuit  423  for counting the current time based on the clock pulse from the quartz oscillator  411 , and correcting the current time based on the received time information; a motor drive circuit  425  for driving stepping motors  43 A,  43 B; and a hand position detection circuit  426  for detecting the hand positions.  
         [0076]     The reception circuit  421  includes an amplifier circuit for amplifying the standard radio signal received by the antenna  5 , a filter for extracting a desired frequency component, a demodulation circuit for signal demodulation, and a decoder circuit for decoding the received signals.  
         [0077]     The storage circuit  422  temporarily stores the time information decoded by the reception circuit  421 , and compares the stored time information decoded from multiple received signals to determine if signal reception was successful.  
         [0078]     The photoelectric generating means  6  generates power from light incident thereon from the dial  21  side, and the generated power is stored in a battery (secondary cell)  49 . A diode preventing the battery  49  from discharging is rendered between the photoelectric generating means  6  and battery  49 . The various electronic circuits are driven by power from the battery  49 .  
         [0079]     The central control circuit  423  includes an oscillation circuit, frequency divider, current time counter for counting the current time, and a time correction circuit for adjusting the count of the current time counter according to the received time information. The central control circuit  423  also has a reception control circuit  424  for storing the reception schedule of the reception circuit  421  and controlling the reception operation. The reception schedule is set so that the standard time signal is received from 2:00 a.m. to 2:06 a.m. When the switching unit  13  is manually operated to send a command to the reception control circuit  424  to force time signal reception, an output signal from the reception control circuit  424  causes the reception circuit  421  to receive.  
         [0080]     The motor drive circuit  425  applies drive pulses to the stepping motors  43 A,  43 B at a timing controlled by the central control circuit  423 .  
         [0081]     The hand position detection circuit  426  detects the positions of the hands (minute hand  221 , hour hand  222 ), and outputs the result to the central control circuit  423 . The central control circuit  423  then compares the detection result from the hand position detection circuit  426  with the current count of the current time counter. Based on the result of this comparison, motor pulses are output to the motor drive circuit  425  so that the value of the counter matches the positions of the hands.  
         [0082]     The drive means includes a minute hand stepping motor  43 A for rotationally driving the minute hand  221 , and an hour hand stepping motor  43 B for rotationally driving the hour hand  222 .  
         [0083]     The stepping motors  43 A,  43 B each have a drive coil  431 A,  431 B for producing magnetic force as a result of drive pulses supplied from the motor drive circuit  425 , a stator  432 A,  432 B excited by the drive coil  431 A,  431 B, and a rotor  433 A,  433 B rotated by the magnetic field excited by the stator  432 A,  432 B. The minute hand stepping motor  43 A is located in approximately the 10:00 direction, and the hour hand stepping motor  43 B is located in approximately the 8:00 direction.  
         [0084]     The stepping motors  43 A,  43 B are rendered such that when seen from the side (that is, when viewing the radio-controlled timepiece  100  from the direction perpendicular to the cylindrical axis L 1  of the case member  1 ), the drive coils  431 A,  431 B are at a position overlapping the gear train holder  47 , and the drive coils  431 A,  431 B are thus disposed proximally to the back cover  3 . The center M in the thickness direction (height direction) of the drive coil  431 A,  431 B is located closer to the back cover  3  than the center C in the thickness direction (height direction) of the movement  4 , that is, closer to the back cover  3  than a position equidistant to the main plate  46  and gear train holder  47 . As a result, the distance M 1  from the center M in the thickness direction of the drive coil  431 A,  431 B to the bottom side of the gear train holder  47  is less than the distance M 2  from the center M in the thickness direction of the drive coil  431 A,  431 B to the top side of the main plate  46 .  
         [0085]     The gear train  44  includes minute hand gear train  44 A, which is linked between the minute hand stepping motor  43 A and the second wheel  444  that rotates in unison with the minute hand shaft  442  to which the minute hand  221  is connected, for transferring rotation of the rotor  433 A,  433 B to the hands  221 ,  222 ; and hour hand gear train  44 B connecting the hour hand stepping motor  43 B to the center wheel  441  to which the hour hand  222  is connected. The gear train  44  can be made from any material providing sufficient strength, including stainless steel or other metal, or ceramic, plastic, or other nonconductive, nonmagnetic material.  
         [0086]     The main plate  46  axially supports the gear train  44  on the dial  21  side, and the gear train holder  47  axially supports the gear train  44  on the back cover  3  side. The main plate  46  and gear train holder  47  are made from a nonconductive, nonmagnetic material such as plastic or ceramic.  
         [0087]     The gear train  44 , stepping motors  43 A,  43 B, and circuit block  42  are integrally rendered between the main plate  46  and gear train holder  47 , forming the movement  4 .  
         [0088]     Note that the photoelectric generating means  6  could be fastened with screws to the movement  4 , or assembled to the movement  4  by means of a spacer member that is snap-fit to the movement  4 .  
         [0089]     The spacer  14  is a ring-shaped member around the inside circumference of the case member  1 , surrounding the outside edge of the movement  4 . The spacer  14  holds the movement  4  inside the case member  1 . The spacer  14  is made from a nonconductive, nonmagnetic material such as plastic or ceramic.  
         [0090]     The battery  49  is a secondary cell for storing power generated by the photoelectric generating means  6 , is connected directly to the photoelectric generating means  6 , and has a metal outside case. The battery  49  is located in approximately the 2:00 direction occupying the space from approximately 1:00 to approximately 3:00.  
         [0091]     The antenna  5  includes a core  51  made from ferrite, amorphous metal, or other high permeability material, and a coil  52  wound in multiple layers to the core  51 . To reduce core loss, the core  51  is made from multiple foil layers so that the external shape when seen in section is substantially rectangular. The foil layers are bonded together with epoxy or other insulating adhesive.  
         [0092]     When seen from a side view of the radio-controlled timepiece  100 , the antenna  5  is rendered with the antenna axis substantially parallel to the plane of the support substrate  62  on the back cover  3  side of the support substrate  62  relative to the photoelectric conversion element  61 , that is, adjacent to the back cover  3  side surface of the support substrate  62  on the opposite side of the support substrate  62  as the photoelectric conversion element  61 . Therefore, when viewed from the direction parallel to the cylindrical axis L 1  of the case member  1 , that is, when seen in the plan view of the radio-controlled timepiece  100 , the antenna  5  is substantially completely covered by the support substrate  62  and photoelectric conversion element  61  of the photoelectric generating means  6 . Note that the antenna  5  can be rendered touching the support substrate  62  or within a specific gap to the support substrate  62 . The specified distance between the antenna  5  and support substrate  62  can be appropriately predetermined to assure good signal reception by the antenna  5  with consideration for the shape of the antenna  5 , and the material and size of the support substrate  62 .  
         [0093]     In this embodiment of the invention the antenna  5  is rendered passing through the main plate  46  and protruding to the photoelectric generating means  6  side with the outside portion of the antenna  5  contacting the bottom of the support substrate  62 . This renders the center N in the thickness direction (height direction) of the core  51  on the dial  21  side of the center C in the thickness direction (height direction) of the movement  4 . The center N in the thickness direction (height direction) of the core  51  is on the dial  21  (that is, photoelectric generating means  6 ) side of the center P in the thickness direction of the metal case member  1 . The distance N 2  from the center N in the thickness direction of the core  51  (antenna  5 ) to the edge of the case member  1  on the opposite side from the back cover  3  (the dial  21  side) is therefore less than the distance N 1  from the center N in the thickness direction of the core  51  (antenna  5 ) to the top of the back cover  3 .  
         [0094]     The antenna  5  is located in about the 6:00 direction when the radio-controlled timepiece  100  is seen in plan view with the antenna axis substantially parallel to the line between the 3:00 direction and 9:00 direction. Furthermore, when the radio-controlled timepiece  100  is seen in plan view, the antenna  5  is disposed opposite the battery  49  with the switching unit  13  therebetween.  
         [0095]     The operation of a radio-controlled timepiece  100  thus comprised according to this first embodiment of the present invention is described next.  
         [0096]     The current time kept by the time counter is updated according to the reference clock generated by frequency dividing oscillations of the quartz oscillator  411 . The hand position detection circuit  426  detects the positions of the hands (minute hand  221 , hour hand  222 ) and outputs the result to the central control circuit  423 . The hand positions and count of the current time counter are then compared, and the stepping motors  43 A,  43 B are driven by means of the motor drive circuit  425  based on the result of this comparison. Rotation of the rotors  433 A,  433 B when the stepping motors  43 A,  43 B are driven is relayed by the gear train  44  to the hands  221 ,  222 , and the current time is indicated by the hands  221 ,  222  pointing to numbers on the time display face  211 .  
         [0097]     Standard time signal reception and adjusting the time based on the time information in the standard time signal are described next.  
         [0098]     The standard radio signal is received by the antenna  5 . Being an electromagnetic wave, the standard radio signal includes electric field fluctuation oscillating perpendicularly to the direction of wave propagation, and magnetic field fluctuation oscillating perpendicularly to the direction of signal propagation and electric field fluctuation. The magnetic field fluctuation passes through the crystal  23 , dial  21 , and photoelectric generating means  6  and passes the core  51  of the antenna  5  and is thereby linked in the axial direction by the coil  52 , producing an induction voltage in the coil  52  whereby the standard radio signal is received.  
         [0099]     At 2:00 a.m., which is the reception starting time preset in the reception control circuit  424 , the reception control circuit  424  outputs a start reception command to the reception circuit  421 . The reception control circuit  424  also outputs the start reception command to the reception circuit  421  when the switching unit  13  is operated to force reception. When the reception circuit  421  receives the start reception command, power is drawn from the battery  49  and the reception circuit  421  starts decoding the signal (time information) received by the antenna  5 .  
         [0100]     The decoded time information is temporarily stored to the storage circuit  422 , and the accuracy of the reception is determined by comparing the time information received in multiple signals (such as six signals). The current time of the current time counter is then updated by the time correction circuit according to the accurately received time information. The hand positions are then adjusted according to the time of the current time counter, and the time is indicated according to the received time.  
         [0101]     When the dial  21  is exposed to light, the light passes through the crystal  23  and dial  21  and is incident on the photoelectric conversion element  61 . Electricity is then produced by photoelectric conversion by the photoelectric conversion element  61 , and the generated power (current) is supplied from the transparent electrodes to the battery  49  and stored. This first embodiment of the present invention thus affords the following benefits.  
         [0102]     (1) Because the support substrate  62  is made from a nonmagnetic material, external magnetic fields can pass through the photoelectric generating means  6 , and the antenna  5  located directly below the photoelectric generating means  6  can receive signals from the dial  21  side with good reception. The antenna  5  is therefore assured of good reception without being affected by the photoelectric generating means  6  while the back cover  3  and case member  1  can be made from metal materials to improve the appearance of the radio-controlled timepiece  100 . In addition, the photoelectric generating means  6  can efficiently receive light and generate power without the antenna  5  interfering with incident light even when the antenna  5  is adjacent to the photoelectric generating means  6 .  
         [0103]     Furthermore, because the support substrate  62  is made from a nonconductive material, the support substrate  62  will not interfere with electric field components contained in the external standard radio signal. The electric field component of the standard radio signal can therefore efficiently pass through the photoelectric generating means  6 , and the antenna  5  can receive signals from the dial  21  side with good reception.  
         [0104]     (2) Because the antenna  5  is located on the back cover  3  side of the photoelectric generating means  6 , and the support substrate  62  is rendered completely overlapping the antenna  5  when the radio-controlled timepiece  100  is seen in plan view, the antenna  5  is completely covered by the photoelectric generating means  6  and cannot be seen from the crystal  23 . The appearance of the radio-controlled timepiece  100  is improved as a result. Furthermore, because signals can be received even with the antenna  5  disposed below the photoelectric generating means  6 , the area of the photoelectric conversion element  61  can be maximized to the inside circumference of the case member  1 , thus increasing the area exposed to light and affording good photoelectric conversion efficiency.  
         [0105]     (3) Because the antenna  5  is disposed in contact with the support substrate  62  on the dial  21  side of the center C of the movement  4  and on the dial  21  side of the center P of the case member  1  in the thickness direction, the antenna  5  can be located proximally to the opening on the dial  21  side (crystal  23  side) of the case member  1 , thus affording good signal reception from this opening and improving the reception sensitivity of the antenna  5 . More specifically, because the distance N 2  from the center N of the antenna  5  to the edge of the case member  1  on the dial  21  side is less than distance N 1  from the center N of the antenna  5  to the back cover  3 , external signals can enter easily from the opening in the case member  1  on the dial  21  side.  
         [0106]     Furthermore, because the antenna  5  is disposed to a position separated from the back cover  3 , signals entering from outside the timepiece can be prevented from being pulled in by the conductive back cover  3 , and good signal reception by the antenna  5  can be reliably assured. Because other components (parts) of the radio-controlled timepiece  100  are not located between the antenna  5  and support substrate  62 , the antenna  5  can reliably receive signals with good reception without other components interfering with signal reception.  
         [0107]     Note that this can also be applied to electronic timepieces with a radio communication function in which a photoelectric generating means  6  is not provided. If the center N of the antenna  5  is on the dial  21  side of the center P of the case member  1 , that is, if distance N 2  from the antenna center N to the edge of the case member  1  on the dial  21  side is less than the distance N 1  from the antenna center N to the back cover  3 , the antenna  5  can more easily receive signals from the opening in the case member  1  on the dial  21  side even if the back cover  3  is made from metal or other electrically conductive material.  
         [0108]     (4) Furthermore, because the drive coils  431 A,  431 B of the stepping motors  43 A,  43 B are rendered proximally to the back cover  3 , the axis of the antenna  5  and the axis of the drive coils  431 A,  431 B can be separated from each other when seen in a side view of the radio-controlled timepiece  100 . Current flow to the drive coil  431 A,  431 B normally produces a weak field around the drive coil  431 A,  431 B, but because these drive coils  431 A,  431 B are separated from the antenna  5 , the effect of this weak field on the antenna  5  can be reduced.  
         [0109]     Furthermore, because the drive coils  431 A,  431 B are located adjacent to the back cover  3 , external signals are prevented from being pulled in by the stators  432 A,  432 B, and the antenna  5  can easily receive signals from the opening on the dial  21  side of the case member  1 .  
         [0110]     (5) Because the switching unit  13  is located between the antenna  5  and battery  49 , the effect of the external metal case of the battery  49  on the magnetic field around the antenna  5  can be minimized, thereby assuring even more reliable, accurate signal reception by the antenna  5 .  
         [0111]     (6) Because the antenna  5  is disposed with the axis thereof substantially parallel to a line through the 3:00 direction and 9:00 direction, signals can be reliably received with good reception by the antenna  5  without the wristwatch band interfering with the signal field even when a metal wristwatch band is attached to the lugs  11 ,  12  because the wristwatch band does not interfere with a line extended along the axis of the antenna  5 .  
         [0112]     (7) Because the dial  21  and crystal  23  are made from a nonconductive and nonmagnetic material, signals entering from the opening on the crystal  23  side of the case member  1  can pass through the dial  21  and crystal  23 . The antenna  5  can therefore receive signals entering from this opening in the case member  1  with good reception.  
       Second Embodiment  
       [0113]     A second embodiment of the present invention is described next. This second embodiment differs from the first embodiment in the arrangement of the photoelectric generating means  6  and antenna  5 .  
         [0114]      FIG. 5  is a plan view of a radio-controlled timepiece  100  according to a second embodiment of the invention, and  FIG. 6  is a section view through line VI-VI in  FIG. 5 . As shown in  FIG. 5  and  FIG. 6 , the photoelectric generating means  6  is a substantially circular disk with area approximately equal to the dial  21  and an approximately C-shaped notch  63  enclosing the antenna  5  is formed according to the shape of the antenna  5  at approximately 6:00. As a result, the antenna  5  and photoelectric generating means  6  are rendered so as to not overlap when the radio-controlled timepiece  100  is seen in plan view. The support substrate  62  is made from stainless steel or other conductive metal material. The material of the support substrate  62  could be a material that is magnetic, nonmagnetic, or has both properties.  
         [0115]     When the radio-controlled timepiece  100  is seen in side view, the antenna  5  is disposed passing through and protruding in part from the photoelectric generating means  6  directly below the dial  21 , that is, adjacent to the side opposite from the time display face  211 . The antenna  5  can be rendered contacting the dial  21  or proximally thereto within a specific gap to the dial  21 .  
         [0116]     With this arrangement the antenna  5  (including the coil  52 ) and the support substrate  62  are mutually overlapping in a side view of the radio-controlled timepiece  100 .  
         [0117]     Note that in this second embodiment the center N in the thickness direction (height direction) of the core  51  of the antenna  5  is on the dial  21  side of the center C in the thickness direction (height direction) of the movement  4 . Furthermore, the center N in the thickness direction (height direction) of the core  51  is on the dial  21  side of the center P in the thickness direction of the metal case member  1 . The distance N 2  from the center N in the thickness direction of the core  51  (antenna  5 ) to the edge of the case member  1  on the dial  21  side is thus less than the distance N 1  from the center N in the thickness direction of the core  51  (antenna  5 ) to the back cover  3 . This arrangement facilitates signal reception by the antenna  5  from the opening in case member  1  on the dial  21  side.  
         [0118]     In addition to the benefits (4), (5), (6), and (7) of the first embodiment described above, this second embodiment of the invention also affords the following benefits.  
         [0119]     (8) By forming a notch  63  in the photoelectric generating means  6 , the antenna  5  can be rendered overlapping the support substrate  62  in a side view of the radio-controlled timepiece  100 . The antenna  5  can therefore be located the thickness of the photoelectric generating means  6  closer to the dial  21 , and closer to the crystal  23  than in the first embodiment. Signals can therefore be received more reliably through the case opening because the antenna  5  is located even closer to the opening in the case member  1 . Because other component parts (members) of the radio-controlled timepiece  100  are not located between the antenna  5  and dial  21  in this embodiment, the antenna  5  is assured of good, reliable reception without other component parts interfering with signals entering the case.  
         [0120]     Furthermore, the antenna  5  is located overlapping the support substrate  62  in a side view of the radio-controlled timepiece  100  at a position on the dial  21  side of the center C of the movement  4  and the dial  21  side of the center P in the thickness direction of the case member  1 . That is, the distance N 2  from the center N of the antenna  5  to the edge of the case member  1  on the dial  21  side is less than the distance N 1  from the center N of the antenna  5  to the back cover  3 . Therefore, as in benefit (3) of the first embodiment, signals can be received with good reception from the dial  21  side opening in the case member  1 , and the reception sensitivity of the antenna  5  can be improved.  
         [0121]     (9) By forming a notch  63  in the photoelectric generating means  6 , the antenna  5  and photoelectric generating means  6  can be rendered without overlapping in a plan view of the radio-controlled timepiece  100 . As a result, the magnetic field entering the antenna  5  will not be obstructed and the antenna  5  is afforded good reception performance even if the support substrate  62  is made from a metal material. The support substrate  62  can therefore be made from either a magnetic or nonmagnetic material, thus providing a wider range of selectable materials, and enabling improving the strength of the photoelectric generating means  6 .  
         [0122]     Note that because there will be no magnetic materials around the antenna  5  if the support substrate  62  is made from a nonconductive and nonmagnetic material, signal reception by the antenna  5  will be unhindered, and even more reliable, good reception performance can be achieved.  
       Third Embodiment  
       [0123]     A third embodiment of the invention is described next. This third embodiment differs from the second embodiment in the configuration of the photoelectric generating means  6  and antenna  5 .  
         [0124]      FIG. 7  is a plan view of a radio-controlled timepiece  100  according to this third embodiment. As shown in  FIG. 7 , the photoelectric generating means  6  is divided into three portions ( 6 A,  6 B,  6 C), and the photoelectric conversion elements  61 A,  61 B,  61 C of these three photoelectric generating means  6 A,  6 B,  6 C are connected in series to improve the electromotive force (voltage). As in the second embodiment, the support substrates  62 A,  62 B,  62 C of these can be made from a conductive, high permeability magnetic material such as amorphous metal, permalloy, or stainless steel.  
         [0125]     Photoelectric generating means  6 B and  6 C are rendered at approximately 4:00 and approximately 8:00 at positions corresponding to the ends of the antenna  5 . These photoelectric generating means  6 B and  6 C are triangularly shaped with substantially the same size as the corresponding photoelectric conversion elements  61 B,  61 C and support substrates  62 B,  62 C. When seen in a plan view of the radio-controlled timepiece  100 , the photoelectric generating means  6 A,  6 B,  6 C do not overlap. The support substrates  62 B,  62 C and photoelectric conversion elements  61 B,  61 C of the photoelectric generating means  6 B,  6 C are mutually insulated, and the photoelectric conversion elements  61 B,  61 C are electrically connected to photoelectric generating means  6 A.  
         [0126]     The photoelectric generating means  6 A is disposed in the direction of 12:00, having an odd shape with a tab protruding from the flat side of a substantially semicircular plate so as to substantially cover the area enclosed between the inside circumference of the case member  1 , the photoelectric generating means  6 B,  6 C, and the antenna  5 . The photoelectric generating means  6 A therefore covers the larger portion of the opening in the case member  1 , has area greater than the photoelectric generating means  6 B,  6 C, and is a major portion of the photoelectric generating means  6 . When seen in a plan view of the radio-controlled timepiece  100 , these photoelectric generating means  6 A,  6 B,  6 C do not overlap.  
         [0127]     The number of segments in the photoelectric generating means  6  shall not be limited to three, and the photoelectric generating means  6  can be segmented into two, four, or other desirable number of parts. Furthermore, the multiple photoelectric generating means  6 A,  6 B,  6 C are not necessarily connected with the photoelectric conversion elements  61 A,  61 B,  61 C in series, and the segments could be parallel connected.  
         [0128]     The antenna  5  is located at approximately 6:00 with the antenna axis substantially parallel to a line through 3:00 and 9:00. The ends of the core  51  have substantially the same triangular shape as the plane shape of the photoelectric generating means  6 B,  6 C, and are electrically connected to the corresponding support substrates  62 B,  62 C by adhesion, welding, or other means.  
         [0129]      FIG. 8  is a partial section view through line VIII-VIII in  FIG. 7 . As shown in  FIG. 8 , both end portions of the core  51  outside of the coil  52  are bent to the photoelectric generating means  6 B,  6 C side. As a result, both ends of the core  51  are located in greater proximity to the dial  21  side (the open side of the case member  1 ), and the photoelectric generating means  6 B,  6 C are disposed in contact with the dial  21 . Note that the photoelectric generating means  6 B,  6 C can be magnetically connected to the core  51  without bending the ends of the core  51 , and as a result the photoelectric generating means  6 B,  6 C can be located separated from the dial  21 .  
         [0130]     In addition to affording the same benefits as benefits (3), (4), (5), (6), and (7) of the first embodiment, this third embodiment of the invention also affords the following benefits.  
         [0131]     (10) Because the support substrates  62 B,  62 C and both ends of the core  51  of the antenna  5  are magnetically connected, the magnetic field of the standard radio signal can be guided to the antenna  5  by the broad area of both ends of the core  51  and the support substrates  62 B,  62 C. Flux linkage can thus be improved, and the reception sensitivity of the antenna  5  can be improved.  
         [0132]     Furthermore, by bonding both end portions of the antenna  5  to the support substrates  62 B,  62 C, the photoelectric generating means  6 B,  6 C can be formed to said portions, and the reception sensitivity of the antenna  5  can be improved without reducing the light receiving area of the photoelectric generating means  6 .  
         [0133]     (11) Unlike the photoelectric generating means  6 B,  6 C guiding the magnetic field to the antenna  5 , the photoelectric generating means  6 A is formed in a shape that does not overlap the antenna  5  when seen in a plan view of the radio-controlled timepiece  100 . As a result, as in benefit (8) of the second embodiment, the support substrate  62 A can be made from a metal or other magnetic material without interfering with signal reception by the antenna  5 . The strength of the photoelectric generating means  6  can therefore be improved.  
         [0134]     Furthermore, because the support substrates  62 A,  62 B,  62 C do not overlap the coil  52  part of the antenna  5  in the plan view of the radio-controlled timepiece  100 , the antenna  5  can be disposed more closely to the crystal  23 , and signals can be dependably received by the antenna  5  as described in benefit (9) of the second embodiment.  
         [0135]     (12) The electromotive force can also be improved because three photoelectric generating means  6 A,  6 B,  6 C are provided connected together in series.  
         [0136]     It should be noted that the present invention shall not be limited to the embodiments described above, and various modifications and improvements capable of achieving the object of the invention are included within the scope of this invention.  
         [0137]     For example, the shape of the photoelectric generating means shall not be limited to the preceding embodiments, and can be desirably determined with consideration for the shape of the outside case and the location of the drive means, for example.  
         [0138]      FIG. 9  is a plan view of a radio-controlled timepiece  100  showing a variation of the photoelectric generating means according to the present invention. As shown in  FIG. 9 , the photoelectric generating means  6  is substantially semicircular in shape with a straight side  64  formed on the 6:00 side of the circle. The straight side  64  is formed parallel to the axis of the antenna  5  along one long side of the antenna  5  exterior, that is, parallel to a line joining 3:00 and 9:00. The antenna  5  and photoelectric generating means  6  therefore do not overlap in a plan view of the radio-controlled timepiece  100 .  
         [0139]     Because the support substrate of the photoelectric generating means  6  does not overlap the antenna  5  when seen in plan view with a photoelectric generating means  6  thus shaped, the antenna  5  can receive signals from the photoelectric generating means  6  side of the case member with good reception even if the support substrate is made from a magnetic material or conductive material. The photoelectric generating means  6  is also not disposed in the area at both ends of the antenna  5  because the photoelectric generating means  6  has a straight side  64 . Therefore, even if the support substrate of the photoelectric generating means  6  is made from a magnetic material or conductive material, for example, the signal field reaches both ends of the antenna  5  from the photoelectric generating means  6  side opening in the case member  1  easily and signals can be received with good reception.  
         [0140]     Signals entering from the dial  21  side can also be easily received in this case because the antenna  5  is rendered directly below adjacent to or in contact with the dial  21 .  
         [0141]     It will thus be apparent that insofar as area sufficient to generate sufficient power to operate the drive means is assured, the shape of the photoelectric conversion means shall not be limited to circular or semicircular, and the photoelectric generating means could be rectangular, triangular, or other desirable shape, including cartoon character shapes, for example.  
         [0142]     The location of the photoelectric generating means can therefore be determined appropriately with consideration for the location of other components as seen in a plan view of the radio-controlled timepiece.  
         [0143]     The shape of the case member shall also not be limited to the cylindrical shape described in the preceding embodiments, and the shape can be determined desirably according to the application and design of the timepiece, including square cylinders and other odd cylindrical shapes. In this case the shape of the photoelectric generating means can be determined according to the internal circumferential shape of the case member, or the photoelectric generating means can be shaped differently than the case member. Note that if the photoelectric generating means is shaped according to the internal circumferential shape of the case member, the area of the photoelectric conversion means can be maximized and good photoelectric conversion efficiency can be achieved.  
         [0144]     The case member shall also not be limited to having both ends thereof open, and could, for example, be a tubular shape with a bottom. In other words, the case member must simply be open on one end. The case member could also be an assembly of multiple integrally assembled external parts, including a body for holding the movement and a bead for holding the crystal. The case member is also not limited to metal components. For example, the surface of a case member made from molded synthetic resin could be coated with a metallic thin film.  
         [0145]     The location of the antenna inside the movement can also be determined as desired. For example, other watch components (component members) can be disposed between the antenna and back cover when the electronic timepiece with radio communication function is seen in side view.  
         [0146]      FIG. 10  is a plan view showing another variation of a radio-controlled timepiece, and  FIG. 11  is a section view through line XI-XI in  FIG. 10 . As in the above embodiments, in  FIG. 10  and  FIG. 11  the antenna  5  is proximally disposed to the dial  21  side in the movement  4 . In this embodiment, gears that are part of the hour hand gear train  44 B driven by hour hand stepping motor  43 B are located between the antenna  5  and gear train holder  47  when seen in a side view of the radio-controlled timepiece  100 . In other words, the hour hand gear train  44 B is located overlapping the antenna  5  when seen in a plan view of the radio-controlled timepiece  100 . A certain amount of space is afforded between the antenna  5  and gear train holder  47  by locating the antenna  5  adjacent to the dial  21 . This space can then be used to hold other component parts of the radio-controlled timepiece  100 , and the space efficiency of the radio-controlled timepiece  100  can be improved. This helps reduce the size of the radio-controlled timepiece  100 . Furthermore, because the hour hand gear train  44 B is located proximally to the antenna  5  in a plan view of the radio-controlled timepiece  100 , a large space is afforded in the 9:00 direction of the radio-controlled timepiece  100 , and the quartz oscillators  412 ,  413 , for example, can be increased in size. The space between the antenna  5  and gear train holder  47  can thus be used efficiently by locating the antenna  5  proximally to the dial  21  side. Furthermore, the hour hand gear train  44 B is not the only component that can be located between the antenna  5  and gear train holder  47 , and the switching unit  13 , circuit block  42 , quartz oscillator unit  41 , or other desirable part or member can be located between the antenna  5  and gear train holder  47  as desired.  
         [0147]     The configuration of a radio-controlled timepiece according to the present invention shall not be limited to the preceding embodiments, and any configuration enabling correcting the displayed time according to a radio signal can be used, including, for example, timepieces having a calendar display function.  
         [0148]      FIG. 12  is a plan view showing an alternative embodiment of the invention, and  FIG. 13  is a section view through line XIII-XIII in  FIG. 12 . As shown in  FIG. 12  and  FIG. 13 , a date wheel  45  is rendered between the movement  4  and photoelectric generating means  6  inside the case member  1 . The date wheel  45  is a ring-shaped gear with an open center portion, and is made of plastic, inorganic glass, paper, or other nonconductive and nonmagnetic material. The date wheel  45  is meshed with the gear train (not shown in the figure) linked from the center wheel  441 , and rotates at a specific speed due to rotation of the center wheel  441 . Letters (not shown in the figure) denoting the date are recorded on the date wheel  45  opposite the dial  21 . A date window  212  enabling the letters on the date wheel  45  to be read from the outside is opened in the 3:00 direction of the dial  21 .  
         [0149]     The photoelectric generating means  6  is formed in a circle with a radius that is greater than the radius of the inside circumference of the date wheel  45 , and the support substrate  62  covers the top inside circumference portion of the date wheel  45  such that the date wheel  45  is held between the support substrate  62  and movement  4 , thus preventing the position of the date wheel to shift in the sectional direction of the date wheel. The photoelectric generating means  6  thus functions as a date wheel presser. Furthermore, the radius of the photoelectric generating means  6  is smaller than the outside circumference radius of the date wheel  45 , thereby enabling the ring part of the date wheel  45  to be seen from the dial  21 . The support substrate  62  is made of polyimide resin or other nonconductive, nonmagnetic material.  
         [0150]     The antenna  5  is located on the inside side of the inside circumference of the date wheel  45  with the antenna axis substantially parallel to a line through 3:00 and 9:00. The antenna  5  and date wheel  45  therefore do not overlap in a plan view of the radio-controlled timepiece  100 .  
         [0151]     Because the support substrate  62  is made from a nonmagnetic material in this embodiment of a radio-controlled timepiece  100 , the antenna  6  can receive signals from the dial  21  with good reception.  
         [0152]     Furthermore, because the photoelectric generating means  6  also functions as a date wheel presser, the parts count can be reduced, the thickness of the radio-controlled timepiece  100  can be reduced, and the manufacturing cost can be reduced.  
         [0153]     Furthermore, because the antenna  4  and date wheel  45  are rendered so that they do not overlap in a plan view of the radio-controlled timepiece  100 , the antenna  5  is afforded good reception performance even if the date wheel  45  is made from a metal material that is both conductive and magnetic.  
         [0154]     As shown in  FIG. 14  and  FIG. 15 , the antenna  5  could also be located overlapping the date wheel  45  in a plan view of the radio-controlled timepiece  100 .  
         [0155]      FIG. 14  is a plan view showing an alternative arrangement of an antenna according to the present invention, and  FIG. 15  is a section view through line XV-XV in  FIG. 14 . As shown in  FIG. 14  and  FIG. 15 , in a plan view of the radio-controlled timepiece  100 , the antenna  5  is disposed in the 6:00 direction at a position more toward the outside circumference inside the case member  1  when compared with the antenna  5  of the radio-controlled timepiece  100  shown in  FIG. 12  and  FIG. 13 . With this arrangement, part of the antenna  5  overlaps the date wheel  45  when seen in a plan view of the radio-controlled timepiece  100 . The date wheel  45  is made of polyacetal resin or other plastic material, and the date window  212  is rendered in the 6:00 direction. Because the antenna  5  is located more on the outside circumference side in the movement  4  with this arrangement, space inside the radio-controlled timepiece  100  can be used efficiently, and greater freedom is afforded in the layout of the other component parts. Furthermore, by locating the antenna  5  on the outside circumference side of a case member  1  that has more internal space, the size of the antenna  5  can be increased and the reception sensitivity of the antenna  5  can be improved.  
         [0156]     Furthermore, in  FIG. 12 ,  FIG. 13 ,  FIG. 14 , and  FIG. 15 , the center N in the thickness direction (height direction) of the 55 core  51  is on the dial  21  side of the center in the thickness direction (height direction) of the movement  4 . In addition, the center N in the thickness direction (height direction) of the core  51  is located on the dial  21  side of the center P in the thickness direction of the case member  1 . The distance N 2  from the center N in the thickness direction of the core  51  (antenna  5 ) to the edge of the case member  1  on the side opposite the back cover  3  is also less than the distance N 1  from the center N in the thickness direction of the core  51  (antenna  5 ) to the back cover  3 . By thus disposing the antenna  5 , the antenna  5  can receive signals from the dial  21  side opening in the case member  1  with good reception. As shown in  FIG. 10  and  FIG. 11 , the hour hand gear train  44 B and other parts of the movement  4  can be disposed between the antenna  5  and gear train holder  47 .  
         [0157]     The shape and configuration of the antenna shall not be limited to the embodiments described above, and can be determined appropriately with consideration for the reception performance of the antenna and the space available in the case member. The antenna could, for example, be a so-called coreless antenna having a hollow center and no core. The antenna core shall also not be limited to a laminated assembly of multiple foil layers, and could be a round or square rod.  
         [0158]     The antenna shall also not be limited to an assembly with the main plate, and could, for example, be mounted on a circuit board.  
         [0159]      FIG. 16  is a side section view showing a variation of the structure for affixing the antenna in the present invention, and  FIG. 17  is an enlargement of the side view in  FIG. 16 . As shown in  FIG. 16  and  FIG. 17 , a circuit board  48  on which the quartz oscillator unit  41  and circuit block  42  are mounted is disposed in the movement  4 . The circuit board  48  is located in contact with the bottom side of the main plate  46  (the side opposite the gear train holder  47 ), and is fastened by screw to the main plate  46 . An aperture  481  is formed in the circuit board  48  at a position corresponding to the location of the antenna  5 ; the coil  52  of the antenna  5  is located inside this aperture  481 , and the core  51  contacts the circuit board  48 . The core  51  is fastened to the circuit board  48  by soldering, adhesion, riveting, or other method. Because the antenna  5  is securely fixed to the circuit board  48  as a result of this method of fastening the antenna  5 , the antenna  5  will not move inside the movement  4  as a result of moving the radio-controlled timepiece  100 , and breaks in the coil  52  and interference with other component parts can be reliably prevented. Note that as shown in  FIG. 17  the angle q between the line from the end of the antenna  5  to the top edge portion on the inside of the case member  1 , and the cylindrical axis L 1  of the case member  1 , is preferably 45° or more as this arrangement enables external signals to efficiently reach the core  51  of the antenna  5  and thus affords good reception even when the case member  1  is metal, for example.  
         [0160]     The antenna could also be shaped with the antenna core bent toward one edge portion of the case member.  
         [0161]      FIG. 18  and  FIG. 19  show variations of the shape of an antenna in the present invention. In the variation shown in  FIG. 18 , the core  51  of the antenna  5  is bent toward the dial  21  at both ends of the coil  52  and is thus inclined toward the opening on the crystal  23  side of the metal case member  1 . In the variation shown in  FIG. 19 , both the core  51  and coil  52  are curved such that the entire antenna  5  is curved toward the dial  21 , and the ends of the core  51  are thus located closer than the coil  52  to the dial  21 . The bending angle or angle of curvature are preferably set so that a line extended from the ends of the antenna  5  passes through the opening in the case in which the crystal  23  is located without intersecting the metal case member  1 .  
         [0162]     If at least one of the two ends of the antenna  5  is thus bent or curved towards one opening in the case member, signals entering from the opening in the case member  1  can easily enter the core  51  of the antenna  5 , and good signal reception can thus be achieved.  
         [0163]     Furthermore, because signal reception performance can be improved by thus curving the antenna towards one opening in the case, the antenna can be assured of good signal reception even if the case member is small. This arrangement thus facilitates reducing the size of the case and affords a greater variety of designs.  
         [0164]     Regarding the relative plan view positions of the antenna and photoelectric generating means, the entire antenna  5  overlaps the photoelectric generating means  6  in a plan view of the radio-controlled timepiece  100  in the first embodiment, and in the second embodiment the antenna  5  and photoelectric generating means  6  are positioned so that they do not overlap in a plan view of the radio-controlled timepiece  100 . The invention shall not be so limited, however, and the antenna could be positioned with part of the antenna overlapping the support substrate of the photoelectric generating means.  
         [0165]      FIG. 20  is a plan view showing an alternative arrangement of the antenna and photoelectric generating means, and  FIG. 21  is a partial section view of  FIG. 20 . As shown in  FIG. 20  and  FIG. 21 , an open portion  65  is formed in the photoelectric generating means  6  at the position corresponding to the core  51  portion at both ends of the antenna  5 . In a plan view of the radio-controlled timepiece  100 , the ends of the antenna  5  in this arrangement do not overlap the support substrate  62 . External signals can therefore pass through this open portion  65  and reach the antenna  5  even if the support substrate  62  is made of stainless steel or other metal, and signals can be received with good reception. Of course, if the support substrate  62  is made of polyimide or other nonmetallic material, the antenna  5  can receive signals even more dependably. Furthermore, because open portions  65  are formed in the photoelectric generating means  6  only at positions corresponding to the end portions of the antenna  5 , a large light receiving area can be assured. The antenna  5  is thus assured of good reception sensitivity while the generating efficiency of the photoelectric generating means  6  is also good.  
         [0166]     The core  51  at both ends of the antenna  5  can be curved toward the support substrate  62  as shown in  FIG. 21  with this arrangement, and this arrangement affords even more reliable signal reception. Because the antenna receives signals as a result of the magnetic field passing through the ends in the axial direction of the coil  52 , (both) end portions of the antenna  5  in particular are preferably not covered by a magnetic material. The middle portion of the antenna  5 , for example, can therefore be covered by the support substrate. The antenna  5  can still receive signals with good reception when thus disposed because the magnetic field can enter from the ends of the antenna  5 . What is important is that the antenna is located so that at least part of the antenna is not covered by the support substrate when seen in a plan view of the radio-controlled timepiece.  
         [0167]     Both ends of the antenna are magnetically connected to the support substrate of the photoelectric generating means in the third embodiment, but the invention shall not be so limited. For example, only one of the two ends of the antenna could be magnetically connected to a support substrate made of a high permeability material. More particularly, it is sufficient if at least one of the ends of the antenna is magnetically connected to a support substrate made of a high permeability material.  
         [0168]     When the antenna and photoelectric generating means are seen in a side view, the antenna  5  is rendered touching the photoelectric generating means  6  in the first embodiment. The invention shall not be so limited, however, and the relative positions of the antenna  5  and photoelectric generating means  6  can be determined appropriately with consideration for where the component parts of the movement  4  are located and from what materials the components of the radio-controlled timepiece  100  are made. For example, insofar as radio signals can reach both ends of the antenna, the antenna  5  can be located separated from the photoelectric generating means  6  with the gap therebetween maintained to a specific dimension.  
         [0169]     In the second embodiment and third embodiment the antenna  5  and photoelectric generating means  6  are rendered in a side view of the radio-controlled timepiece  100  with a portion of the antenna  5  at a position overlapping the photoelectric generating means  6 . The invention shall not be so limited, however, and the antenna  5  and photoelectric generating means  6  can be positioned with a specific gap therebetween and not overlapping when seen in a side view.  
         [0170]     Regarding the position of the antenna in a side view of the radio-controlled timepiece, the center of the antenna is offset from the center of the case member in proximity to the cover member side. However, when the back cover  3  protrudes to the outside from the bottom edge of the case member  1  as shown in  FIG. 2 , the center of the antenna may be disposed on the support substrate  62  side (the dial  21  side, crystal  23  side) from the center of the distance from the top edge of the case member  1  to the bottom edge of the back cover  3 . Furthermore, when the back cover  3  is shaped curving upward from the bottom edge of the case member  1 , the center of the antenna can be set to the support substrate  62  side relative to the center of the distance from the top edge to the bottom edge of the case member  1 . That is, the center of the antenna must be positioned on the support substrate side from the center of the case member portion including the case member and back cover, in which case the center of this case member portion is the center of the greatest distance in the thickness direction (along the cylindrical axis of the case member) through the case member and the back cover.  
         [0171]     The shape of the antenna is also not limited to configurations that appear straight when seen in a plan view of the radio-controlled timepiece.  
         [0172]      FIG. 22  is a plan view of an antenna with an alternative shape. As shown in  FIG. 22  this antenna  5  is shaped in an arc following the inside shape of the case member  1 . The antenna  5  is also disposed along the outside shape of the dial  21 , and is located inside this dial  21  in a plan view of the radio-controlled timepiece  100 . Compared with rendering the antenna  5  in a straight line, this shape of the antenna  5  reduces the amount of dead space inside the case member  1  and thus affords greater freedom in the layout of other components.  
         [0173]      FIG. 23  and  FIG. 24  show a variation in the location of the antenna,  FIG. 23  being a plan view of the radio-controlled timepiece  100  and  FIG. 24  being a partial side section view of the radio-controlled timepiece  100  shown in  FIG. 23 . In  FIG. 23  and  FIG. 24  the antenna is substantially arc-shaped conforming to the inside of the case member  1 , and the outside curve of the antenna  5  is housed within a recess  1 A formed in the spacer  14  and case member  1 . This results in part of the antenna  5  overlapping the case member  1  in a plan view of the radio-controlled timepiece  100 . Note that in this case the area of the portion of the antenna  5  that overlaps the case member  1  (the area in a plan view of the radio-controlled timepiece  100 ) is preferably less than half of the total area of the antenna  5 . This disposition maintains the good reception sensitivity of the antenna  5  while using space inside the case member  1  efficiently and affording even greater freedom in the layout of other components.  
         [0174]     The coil of the electromagnetic motors is disposed in proximity to the back cover  3  in these embodiments of the present invention, but the invention shall not be so limited. For example, the center in the thickness direction of the coil could be located on the dial side of the center in the thickness direction of the movement. If the coil and antenna are separated from each other in a plan view of the radio-controlled timepiece, or if signal reception by the antenna is stopped when the motors are operating, the antenna  5  can still receive signals correctly and the object of the invention can be achieved.  
         [0175]     In the second and third embodiments the support substrate  62  can be made from a nonconductive and nonmagnetic material such as polyimide resin, glass-impregnated epoxy, or ceramic as in the first embodiment, or it could be made from a conductive, magnetic material such as stainless steel. If the support substrate  62  is made from a nonmagnetic material, however, there is less magnetic material around the antenna  5  and reception by the antenna  5  is thus more reliable.  
         [0176]     It is also possible to make only the photoelectric generating means  6 A in the third embodiment from a nonconductive and nonmagnetic material.  
         [0177]     The switching unit  13  and gear train  44  are disposed between the battery and antenna in the preceding embodiments, but the invention shall not be so limited. The quartz oscillator unit  41  and circuit block  42 , for example, could also be located between the battery and antenna. The effect of the metal case member of the battery on the magnetic field around the antenna can thus be minimized. More specifically, it is only necessary to dispose at least one of the switching unit, gear train, quartz oscillation unit, and control unit between the battery and antenna.  
         [0178]     It will also be apparent that if such other component is not disposed between the battery and antenna, signal reception by the antenna can be enabled by changing the orientation of the antenna or the material of the battery case, and the object of the present invention can be achieved.  
         [0179]     The drive means is also not limited to an electromagnetic motor, and any desirable construction capable of driving the time display means can be used, including, for example, a piezoelectric actuator that operates using the vibrations of a piezoelectric element. In this case a flat piezoelectric element is adhesively bonded to a substantially square reinforcing plate, and a protrusion is formed on the reinforcing plate to form the piezoelectric actuator. A rotor or other rotating body engages the gear train, and the protrusion of the piezoelectric actuator contacts the side of this rotor. When an AC voltage is then applied to the piezoelectric element, the piezoelectric element vibrates, and the repeated pressure of the protrusion tangentially to the rotor causes the rotor to rotate. The gear train then relays this rotary motion to drive the time display means.  
         [0180]     A piezoelectric actuator does not produce a magnetic field during operation, this drive means therefore has no effect on the magnetic field around the antenna, and signals can therefore be correctly received by the antenna.  
         [0181]     The time display means is also not limited to having both an hour hand and a minute hand, and could have only an hour hand, or only a minute hand. A second hand could also be provided.  
         [0182]     The dial can also be rendered with no letters, numbers, or other marks or decoration. The dial itself could also be omitted. If the dial is not provided, the photoelectric generating means could be used as the dial. In this case the photoelectric generating means uses a transparent material such as inorganic glass for the support substrate to form the dial, and the photoelectric conversion unit is rendered on the cover member side of this support substrate. The cover-side surface of this dial and support substrate could also be decorated with letters, markings, or a pattern, for example. If the antenna is located opposite or proximally to the surface on the cover member side of the photoelectric conversion unit in this configuration, the antenna can receive signals with good reception from the opening on one side of the case member, that is, from the photoelectric generating means side.  
         [0183]     The material of the gear train can be desirably determined with consideration for the location of the antenna and the transfer power, and materials such as stainless steel that are conductive and magnetic, or materials that are nonconductive and nonmagnetic such as plastic or ceramic, could be used.  
         [0184]     An electronic timepiece with a radio communication function shall also not be limited to analog timepieces having a dial and hands, and as shown in  FIG. 25 , for example, could be a digital watch  100 A having a liquid crystal panel  2 A as the time display means for digitally indicating the time, and a parting member  2 B. The electronic timepiece with a radio communication function could also have, in addition to the time display function of the time display means, a chronograph function or alarm function, for example.  
         [0185]     An electronic timepiece with a radio communication function shall also not be limited to a radio-controlled timepiece that receives an external standard time signal and adjusts the displayed time, and could be a timepiece having a function for externally transmitting radio frequency information, or a function for both receiving and sending radio frequency information. For example, the electronic timepiece with a radio communication function could be a watch having an internal contactless IC card for communicating RF information with an external device via the antenna (contactless data communication).  
         [0186]     While the various embodiments including a best mode of the present invention have been described in conjunction with the accompanying figures, the invention shall not be so limited. Specific descriptions of shapes, materials, and other aspects of the invention in the foregoing embodiments are offered herein simply by way of example to facilitate understanding the present invention, not to limit the invention. Various modifications to the shape, materials, quantities, and other details of the foregoing embodiments will be apparent to one with ordinary skill in the related art in light of the foregoing description. The present invention is intended to embrace all such modifications as may fall within the spirit and scope of the appended claims.