Patent Publication Number: US-2020301370-A1

Title: Movement of electronic timepiece and electronic timepiece

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a national stage application of PCT Application No. PCT/JP2018/029625, filed on Aug. 7, 2018, which is based on and claims priority to Japanese Patent Application No. 2017-172946, filed on Sep. 8, 2017, the disclosures of which are hereby incorporated by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     This disclosure relates to a movement of an electronic timepiece and an electronic timepiece. 
     BACKGROUND ART 
     In an electronic timepiece that drives a pointer by a stepping motor, a movement includes a magnetic shielding plate for protecting the stepping motor from an external magnetic field. The magnetic shielding plate generally covers the stepping motor from an upper side and a lower side thereof in a thickness direction. Recently, the electronic timepiece is diversified, and is provided with many stepping motors depending on respective functions. However, if each of the stepping motors is provided with the magnetic shielding plate, the number of magnetic shielding plates increases, resulting in an increase in costs. 
     Such an increase in costs is prevented by covering a plurality of stepping motors with a single large magnetic shielding plate (see JP2017-026461A, for example). The costs are further reduced by increasing the size of the magnetic shielding plate such that the magnetic shielding plate is also used as a bridge that supports a component except for the stepping motor, so as to eliminate the need for the bridge. 
     SUMMARY 
     However, when the size of the magnetic shielding plate is increased, the magnetic shielding plate may cover, other than the stepping motor, a portion including a component that does not require a magnetic shielding performance. As the size of the magnetic shielding plate is increased, the more area of the magnetic shielding plate is exposed to an external magnetic field, resulting in an increase in magnetism flowing in the magnetic shielding plate. 
     The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a movement of an electronic timepiece and a timepiece capable of reducing magnetic influence on the stepping motor covered by the magnetic shielding plate. 
     A first aspect of the present disclosure is a movement of an electronic timepiece, including: a stepping motor having a rotor, a stator, and a coil in which a conductive wire is wound around a coil winding core; and a magnetic shielding plate that covers at least a part of the stepping motor, wherein the magnetic shielding plate includes a magnetic flow changing portion that changes a magnetic flow which is directed toward the coil winding core to a magnetic flow which is not directed toward the coil winding core, and the magnetic flow changing portion is formed in a portion of the magnetic shielding plate, which corresponds to each of extended lines from both end portions of the coil winding core, to intersect with the extended line. 
     A second aspect of the present disclosure is an electronic timepiece in which the movement of the electronic timepiece according to the present disclosure is housed inside a case. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a partially transparent view illustrating one embodiment of an electronic timepiece according to the present disclosure, and representing a movement illustrated by a solid line, which is seen from a back cover side by virtually passing through a case illustrated by a two-dot chain line. 
         FIG. 2  is a plan view illustrating arrangement of a stepping motor and a magnetic shielding plate in the movement illustrated in  FIG. 1 . 
         FIG. 3  is a schematic view illustrating a slit having a longer side in a specific direction. 
         FIG. 4  is a schematic view illustrating a plurality of circular holes which play the same role as the slit in  FIG. 3  and are arranged in the specific direction. 
         FIG. 5  is a plan view illustrating arrangement of a stepping motor and a magnetic shielding plate in a movement of Modified Example 1. 
         FIG. 6  is a plan view illustrating arrangement of a stepping motor and a magnetic shielding plate in a movement of Modified Example 2. 
         FIG. 7  is a schematic view illustrating a variation (Modified Example 3) of arrangement of two stepping motors and formation of slits in a magnetic shielding plate when a movement of an electronic timepiece according to another embodiment of the present disclosure includes the two stepping motors. 
         FIG. 8  is a schematic view illustrating a variation (Modified Example 4) of arrangement of two stepping motors and formation of slits in a magnetic shielding plate when a movement of an electronic timepiece according to another embodiment of the present disclosure includes the two stepping motors. 
         FIG. 9  is a schematic view illustrating a variation (Modified Example 5) of arrangement of two stepping motors and formation of slits in a magnetic shielding plate when a movement of an electronic timepiece according to another embodiment of the present disclosure includes the two stepping motors. 
         FIG. 10  is a schematic view illustrating a variation (Modified Example 6) of arrangement of two stepping motors and formation of slits in a magnetic shielding plate when a movement of an electronic timepiece according to another embodiment of the present disclosure includes the two stepping motors. 
         FIG. 11  is a schematic view illustrating a variation (Modified Example 7) of arrangement of a stepping motor and formation of slits in a magnetic shielding plate when a movement of the electronic timepiece according to another embodiment of the present disclosure includes two coils. 
         FIG. 12  is a schematic view illustrating Modified Example in which a battery (one example of magnetic material) is arranged instead of the single stepping motor in  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an embodiment of a movement of an electronic timepiece and an electronic timepiece according to the present disclosure will be described with reference to the drawings. 
     &lt;Configuration of Electronic Timepiece&gt; 
       FIG. 1  is a partially transparent view illustrating an electronic timepiece  1  as one embodiment of the electronic timepiece according to the present disclosure, and representing a movement  3  illustrated by a solid line, which is seen from a back cover side virtually passing through a case  2  illustrated by a two-dot chain line.  FIG. 1  shows, in an upper side thereof, a 12 o&#39;clock direction and, in a left side thereof, a 3 o&#39;clock direction.  FIG. 2  is a plan view illustrating the arrangement of a stepping motor  10  and a magnetic shielding plate  50  in the movement  3  illustrated in  FIG. 1 . 
     In the electronic timepiece  1 , the movement  3  is housed inside the metal case  2 . The electronic timepiece  1  is a radio controlled timepiece including an operation that receives radio wave, and automatically corrects a pointer for indicating a time with the movement  3  based on the received radio wave. The electronic timepiece  1  includes a solar cell panel and a secondary battery, generates electricity with the solar cell panel, and drives the movement  3  by electric power stored in the secondary battery. 
     &lt;Configuration of Movement&gt; 
     The movement  3  is one embodiment of a movement of an electronic timepiece according to the present disclosure. The movement  3  includes the stepping motor  10 , push buttons (PB)  41 ,  42 , PB click springs  31 ,  32  (refer to  FIG. 2 ), and the magnetic shielding plate  50 . The stepping motor  10  drives a train wheel for rotating a pointer for displaying a time with supplied electric power stored in the secondary battery. A user pushes the push buttons (PB)  41 ,  42  for switching various operations of the electronic timepiece  1  and for inputting a specific operation. The PB click springs  31 ,  32  (refer to  FIG. 2 ) produce a click feeling as a reaction force of a pushed operation. 
     In addition to the above-described configurations, the movement  3  includes a mechanism of manually correcting an indicated position of a pointer, another mechanism, and another component. However, they are not necessary for describing the electronic timepiece  1  of the present embodiment, and the description for them are thus omitted. 
     As illustrated in  FIG. 2 , the stepping motor  10  includes a coil  11 , stators  12 , and a rotor  13 . The coil  11  includes a linearly extending coil winding core  11   a  and a conductive wire lib. The conductive wire  11   b  is spirally wound around the coil winding core  11   a . The stators  12  are connected to a first end portion  11   c  of the coil winding core  11   a  and a second end portion  11   d  of the coil winding core  11   a . The stators  12  also have an end portion opposite to the end portion connected to the first end portion  11   c  and an end portion opposite to the end portion connected to the second end portion  11   d , respectively. These end portions of the stators  12  face to each other across the rotor  13 . 
     As illustrated in  FIG. 2 , the magnetic shielding plate  50  is arranged to cover the entire stepping motor  10  except for the coil  11  in a plan view. The coil  11  of the stepping motor  10  has a thickness larger than those of the stators  12  and the rotor  13 . The magnetic shielding plate  50  therefore includes an opening portion  53  through which the coil  11  passes in the thickness direction, so as to prevent interference with the coil  11 . 
     In addition, although the magnetic shielding plate  50  may cover the coil  11 , it is not necessary to cover the entire stepping motor  10 . More specifically, the magnetic shielding plate  50  should cover at least the rotor  13 , a portion over an extended line  16   a  in an extending direction of the coil winding core  11   a  from the first end portion  11   c , and a portion over an extended line  16   b  in an extending direction of the coil winding core  11   a  from the second end portion  11   d.    
     As the magnetic shielding plate  50  is to prevent or control magnetism, which is generated and flown inside the electronic timepiece  1  due to the external magnetic field of the electronic timepiece  1 , from flowing in the stepping motor  10 , the magnetic shielding plate  50  is originally required to have a size that covers only the stepping motor  10 . On the other hand, the magnetic shielding plate  50  of the present embodiment has a size larger than that of the stepping motor  10 . A part of the magnetic shielding plate  50  (that is not required to serve as magnetic shielding plate  50 ) except for a part of the magnetic shielding plate  50  that covers the stepping motor  10  serves as a bridge that supports, for example, the train wheel and the PB click springs  31 ,  32 . 
     Although the movement  3  of the present embodiment includes only the single stepping motor  10 , the movement  3  may include two or more stepping motors  10 . Even when the movement  3  includes the two or more stepping motors  10 , the single magnetic shielding plate  50  can cover the two or more stepping motors  10 . Accordingly, such a configuration having the single magnetic shielding plate  50  can reduce the costs to be lower than that of a configuration having a plurality of small magnetic shielding plates to be provided for a plurality of stepping motors, respectively. 
     The magnetic shielding plate  50  also supports the PB click springs  31 ,  32 , for example. The configuration having such a magnetic shielding plate  50  can reduce the costs to be lower than that of a configuration having a bridge that supports the PB click springs  31 ,  32 , in addition to the magnetic shielding plate  50 . 
     Slits  51 ,  52  intersecting with the extended lines  16   a ,  16   b , respectively, are formed in parts (portions corresponding to extended lines) of the magnetic shielding plate  50  that cover the extended lines  16   a ,  16   b  in the longitudinal direction of the coil winding core  11   a  from both of the end portions  11   c ,  11   d  of the coil winding core  11   a . These slits  51 ,  52  have a length in the longitudinal direction (direction intersecting with extended lines  16   a ,  16   b ) larger (longer) than a diameter of the coil  11  in which the conductive wire  11   b  is wound around the coil winding core  11   a . These slits  51 ,  52  have, over the extended lines  16   a ,  16   b , a width in the width direction (direction along extended lines  16   a ,  16   b  (longitudinal direction of coil winding core  11   a )) larger (wider) than the diameter of the coil winding core  11   a.    
     According to the movement  3  and the electronic timepiece  1  configured as described above, the direction of the external magnetic field that may affect the operation of the stepping motor  10  corresponds to the longitudinal direction of the coil  11  of the stepping motor  10 . As illustrated in  FIG. 2 , when the magnetic shielding plate  50  in the present embodiment is exposed by the external magnetic field which causes a magnetic flow T 1  directed toward the coil  11  from the direction of the extended line  16   a  of the coil  11 , the magnetic flow T 1  in the magnetic shielding plate  50  is blocked by the slit  51  formed near the coil  11  from flowing in the coil  11 . 
     The magnetic flow T 1  is then changed to flows T 1   a , T 1   b  which are not directed toward the coil  11 , namely, which are directed along an end portion of the magnetic shielding plate  50  outside the slit  51 . Namely, the slit  51  is one example of a magnetic flow changing portion that changes the magnetic flow T 1  which is directed toward the coil  11  to the magnetic flow which is not directed toward the coil  11 . 
     As illustrated in  FIG. 2 , when the magnetic shielding plate  50  in the present embodiment is exposed by the external magnetic field which causes a magnetic flow T 2  directed toward the coil  11  from the direction of the extended line  16   b  of the coil  11 , the magnetic flow T 2  in the magnetic shielding plate  50  is blocked by the slit  52  formed near the coil  11  from flowing in the coil  11 . 
     The magnetic flow T 2  is then changed to flows T 2   a , T 2   b  which are not directed toward the coil  11 , namely, which are directed along the end portion of the magnetic shielding plate  50  outside the slit  52 . Namely, the slit  52  is one example of the magnetic flow changing portion that changes the magnetic flow T 2  which is directed toward the coil  11  to the magnetic flow which is not directed toward the coil  11 . 
     As described above, according to the movement  3  of the electronic timepiece  1  and the electronic timepiece  1  of the present embodiment, the magnetic flows T 1 , T 2  in the longitudinal direction of the coil  11  by which the stepping motor  10  is easily most affected are prevented or controlled from flowing in the stepping motor  10  covered by the magnetic shielding plate  50 . It may therefore become difficult for the stepping motor  10  covered by the magnetic shielding plate  50  to be affected by the magnetic flows T 1 , T 2 . 
     The magnetic flow T 1   a  having a direction changed by the slit  51  is directed toward a supporting portion  56   a  that supports the PB click spring  31  as one example of a component which does not require a magnetic shielding performance. The magnetic flow T 1   b  having a direction changed by the slit  51  is also directed to a supporting portion  56   b  that supports a component except for the stepping motor  10 . Accordingly, the movement  3  and the electronic timepiece  1  of the present embodiment can effectively use portions that receive the magnetic flows T 1   a , T 1   b  (magnetic flow bypass portion that bypasses magnetic flow T 1 ) as the supporting portions  56   a ,  56   b.    
     Similarly, the magnetic flow T 2   a  having a direction changed by the slit  52  is directed toward a supporting portion  56   c  that supports the PB click spring  32  as one example of a component which does not require the magnetic shielding performance. The magnetic flow T 2   b  having a direction changed by the slit  52  is directed to a supporting portion  56   d  that supports a component except for the stepping motor  10 . Accordingly, the movement  3  and the electronic timepiece  1  of the present embodiment can effectively use portions that receive the magnetic flows T 2   a , T 2   b  (magnetic flow bypass portion that bypasses magnetic flow T 2 ) as the supporting portions  56   c ,  56   d.    
     In the movement  3  of the electronic timepiece  1  and the electronic timepiece  1  of the present embodiment, the slits  51 ,  52  penetrating through the magnetic shielding plate  50  in the thickness direction are provided as the magnetic flow changing portions in the present disclosure. However, the magnetic flow changing portion is not limited to a slit having a longer side in a specific direction. More specifically, the magnetic flow changing portion in the present disclosure may be a hole penetrating through the magnetic shielding plate  50  in the thickness direction or may be a cutout formed in an end portion of the magnetic shielding plate  50 . The hole may have a circular shape, a rectangular shape, or another shape. 
     As illustrated in  FIG. 3 , the slits  51 ,  52  are formed to have an elongated shape having a length in the longitudinal direction as L. However, as illustrated in  FIG. 4 , for example, a plurality of circular holes  51   a  may be formed instead of the elongated slits  51 ,  52 . In this case, the circular holes  51   a  are arranged in a line at intervals  54 , and each of the circular holes  51   a  has a diameter D L) having a length in the longitudinal direction smaller than that of each of the slits  51 ,  52 . 
     By forming the magnetic flow changing portion with a plurality of holes  51   a  instead of the single long slit  51 ,  52 , a strength of the magnetic shielding plate  50  may be maintained stronger than that of the magnetic shielding plate  50  in which the single slit  51 ,  52  is formed because the portions of the intervals  54  remain as the magnetic shielding plate  50 . In addition, the number of circular holes  51  to be arranged may be the number corresponding to the length L of the single slit  51 ,  52  in the longitudinal direction. 
     The slits  51 ,  52  are not limited to a shape having the same width in any position in the longitudinal direction. The slits  51 ,  52  may be a shape having a different width in each position in the longitudinal direction. When the slits  51 ,  52  are substituted with a plurality of circular holes  51   a , it may not be necessary for a plurality of holes  51   a  to have the same diameter D. Moreover, the slits  51 ,  52  are not limited to a shape having an approximate I shape external outline, and may be a shape having a different external outline such as a C shape and an L shape. 
     The magnetic flow changing portion in the present disclosure is not limited as long as it is configured to change the magnetic flows T 1 , T 2  which are directed toward the coil  11  to the magnetic flows T 1   a , T 1   b , T 2   a , T 2   b  which are not directed toward the coil  11 . Namely, the magnetic flow changing portion in the present disclosure is not limited as long as it is configured such that the magnetism easily flows in the directions different from the direction of the coil  11  rather than the direction of the coil  11 . Accordingly, instead of the slits  51 ,  52  that penetrate through the magnetic shielding plate  50  in the thickness direction as the magnetic flow changing portion, a groove having a longer side in a specific direction may be provided. Such a groove has a thickness smaller than that of another portion. Instead of the hole that penetrates through the magnetic shielding plate  50  in the thickness direction, a recess (concave portion) having a thickness smaller than that of another portion may be provided. 
     In the movement  3  of the electronic timepiece  1  and the electronic timepiece  1  of the present embodiment, the slits  51 ,  52  are formed outside both of the end portions  11   c ,  11   d  of the coil  11 . It is necessary for the slits  51 ,  52  to be formed to correspond to the outsides of both of the end portions  11   c ,  11   d  of the coil  11 . If the magnetic flow is fixed in one direction, the slits  51 ,  52  may be provided only in a portion corresponding to the first end portion  11   c  of the coil  11  or the second end portion  11   d  of the coil  11  such that the slits are suitable only for the magnetism in the one direction of the flow. 
     When the electronic timepiece  1  is a watch to be carried to various places, it is, however, rare that such a watch is used in an environment where the magnetic flow is fixed in one direction. Accordingly, it is practically preferable for the slits  51 ,  52  to be formed in the portions of the magnetic shielding plate  50  that correspond to the outsides of both of the end portions  11   c ,  11   d  of the coil  11 . 
     The slits  51 ,  52  in the present embodiment extend along the external outline of the stators  12  to surround a part of the stators  12  from the outside. Such slits can effectively eliminate the influence of the external magnetic field to the stators  12 . However, the magnetic flow changing portion in the present disclosure may not be limited to a shape along the external outline of the stators. 
     In the present embodiment, the length of the slits  51 ,  52  in the longitudinal direction is larger than the diameter of the coil  11 , and the width of the slits  51 ,  52  is larger than the diameter of the coil winding core  11   a . However, in the present disclosure, the length of the magnetic flow changing portion in the longitudinal direction may be smaller than the diameter of the coil  11 , and the width of the magnetic flow changing portion may be smaller than the diameter of the coil winding core  11   a.    
     The supporting portions  56   a , . . . ,  56   d  of the magnetic shielding plate  50  are not limited to the portions that support the PB click springs  31 ,  32 , and may be portions that support other components of the movement  3 . The supporting portions  56   a , . . . ,  56   b  are not limited to the portions that support components, and may serve as portions that receive the magnetic flows T 1   a , T 1   b , T 2   a , T 2   b  whose directions are changed by the slits  51 ,  52 . 
     In addition, when the movement has a plurality of stepping motors, a portion that covers the stepping motor having a lowest frequency of use may be used as a portion in which the magnetism flows as the supporting portion. 
     Modified Example 1 
       FIG. 5  is a plan view illustrating arrangement of stepping motors  110 ,  120  in a movement  103  of an electronic timepiece  101  and a magnetic shielding plate  150  as another embodiment (Modified Example 1) of the present disclosure. The illustrated electronic timepiece  101  has the same basic configuration as the electronic timepiece  1  illustrated in  FIG. 1 , and only differs from the electronic timepiece  1  illustrated in  FIG. 1  in the movement  103 . 
     Different from the movement  3 , the movement  103  includes the two stepping motors  110 ,  120 , and a single magnetic shielding plate  150  covers the two stepping motors  110 ,  120 . 
     In addition to a hole  153  that avoids a coil  111  of the stepping motor  110  and a hole  156  that avoids a coil  121  of the stepping motor  120 , holes  151 ,  152  intersecting with extended lines  116   a ,  116   b , respectively, are formed in portions (portions corresponding to extended lines) of the magnetic shielding plate  150 , which cover the extended lines  116   a ,  116   b  of a coil winding core  111   a  in the longitudinal direction from both end portions  111   c ,  111   d  of the coil winding core  111   a  of the coil  111 . 
     Similarly, holes  154 ,  155  intersecting with extended lines  126   a ,  126   b , respectively, are formed in portions (portions corresponding to extended lines) of the magnetic shielding plate  150 , which cover the extended lines  126   a ,  126   b  of a coil winding core  121   a  in the longitudinal direction from both end portions  121   c ,  121   d  of the coil winding core  121   a  of the coil  121 . 
     When the movement  103  and the electronic timepiece  101  configured above are exposed by an external magnetic field that generates magnetic flows T 1 , T 2  toward the coil  111  from the directions of the extended lines  116   a ,  116   b  of the coil  111 , the magnetic flows T 1 , T 2  in the magnetic shielding plate  150  are blocked by the rectangular hole  151  and the circular hole  152  formed near the coil  111  from flowing in the coil  111 , and are changed to flows T 1   a , T 1   b , T 2   a , T 2   b  which are not directed toward the coil  111 . 
     The magnetic shielding plate  150  includes supporting portions  157   a ,  157   b ,  157   c ,  157   d  (it is not necessary for supporting portions to actually support specific components as long as they include areas that can support components) that support other components except for the stepping motors  110 ,  120 , and the supporting portions receive the flows T 1   a , T 1   b , T 2   a , T 2   b  which are not directed toward the coil  111 . That is, the magnetic shielding plate  150  effectively uses the portions receiving the magnetic flows T 1   a , T 1   b , T 2   a , T 2   b  as the supporting portions  157   a ,  157   b ,  157   c ,  157   d.    
     Similarly, when the movement  103  and the electronic timepiece  101  are exposed by an external magnetic field that generates magnetic flows T 3 , T 4  which are directed toward the coil  121  from the directions of the extended lines  126   a ,  126   b  of the coil  121 , the magnetic flows T 3 , T 4  in the magnetic shielding plate  150  are blocked by the rectangular holes  154 ,  155  formed near the coil  121  from flowing in the coil  121 , and are changed to flows T 3   a , T 3   b , T 4   a , T 4   b  which are not directed toward the coil  121 . 
     The magnetic shielding plate  150  includes supporting portions  157   e ,  157   f ,  157   g ,  157   h  (it is not necessary for supporting portions to actually support specific components as long as they include portions that can support components) that support other components except for the stepping motors  110 ,  120  as the portions that receive the flows T 3   a , T 3   b , T 4   a , T 4   b  which are not directed toward such a coil. 
     As described above, according to the movement  103  of the electronic timepiece  101  and the electronic timepiece  101 , the magnetic flows T 1 , T 2  in the longitudinal direction of the coil  111  by which the stepping motor  110  is easily affected can be prevented or controlled from flowing in the stepping motor  110  covered by the magnetic shielding plate  150 , and the magnetic flows T 3 , T 4  in the longitudinal direction of the coil  121  by which the stepping motor  120  is easily affected can be prevented or controlled from flowing in the stepping motor  120  covered by the magnetic shielding plate  150 . It becomes difficult for the stepping motor  110  covered by the magnetic shielding plate  150  to be affected by the magnetic flows T 1 , T 2 , and it becomes also difficult for the stepping motor  120  covered by the magnetic shielding plate  150  to be affected by the magnetic flows T 3 , T 4 . 
     According to the movement  103  of the electronic timepiece  101  and the electronic timepiece  101 , the single magnetic shielding plate  150  covers the two stepping motors  110 ,  120 . Such a configuration reduces the costs to be lower than that of a configuration in which two magnetic shielding plates cover two stepping motors, respectively. 
     Moreover, as the holes  151 ,  152 ,  154 ,  155  as the magnetic flow changing portions are formed in the magnetic shielding plate  150  in accordance with the stepping motors  110 ,  120 , respectively, all of the stepping motors  110 ,  120  are controlled from being affected by the external magnetic field. 
     In addition, in the movement  103 , another component  104  (for example, conductive spring for alarm) arranged in a range corresponding to a range inside the external outline of the magnetic shielding plate  150  may be arranged in the hole  152  as the magnetic flow changing portion. Such a configuration which arranges another component  104  in the hole  152  allows a space to be used more effectively than a configuration that uses the hole  152  only as the magnetic flow changing portion. 
     Modified Example 2 
       FIG. 6  is a plan view illustrating arrangement of a stepping motor  210  and a magnetic shielding plate  250  in a movement  203  of an electronic timepiece  201  as another embodiment (Modified Example 2) of the present disclosure. The illustrated electronic timepiece  201  includes the same basic configuration as the electronic timepiece  1  illustrated in  FIG. 1 , and only differs from the electronic timepiece  1  illustrated in  FIG. 1  in the movement  203 . 
     Different from the movement  3 , in the movement  203 , a magnetic shielding plate  250  that covers the stepping motor  210  includes a ring like magnetic shielding plate  250   a  (hereinafter, ring magnetic shielding plate) that covers an outer circumference portion of the movement  203  and a plate like magnetic shielding plate  250   b  (hereinafter, “plate magnetic shielding plate”) that covers the entire movement  203  including the ring magnetic shielding plate  250   a.    
     The ring magnetic shielding plate  250   a  is formed along an external form of the movement  203 . The ring magnetic shielding plate  250   a  includes, in a part thereof (for example, 3 o&#39;clock position of timepiece  201 ), a cutout. A winding stem  205  is provided at a position (portion overlapped with cutout  250   a   1  in plan view) corresponding to the cutout portion (cutout)  250   a   1 . The winding stem  205  extends from the outside of the ring magnetic shielding plate  250   a  in a direction toward a center C of the movement  203  (center of ring of ring magnetic shielding plate  250   a ), and is inserted through the inside of the ring magnetic shielding plate  250   a.    
     The ring magnetic shielding plate  250   a  does not overlap with the stepping motor  210  in the thickness direction, but is arranged to surround the stepping motor  210  from the outside in the radial direction of the movement  203 , and shields the magnetic flow to the movement  203  from the external magnetic field of the movement  203 . The ring magnetic shielding plate  250   a  is arranged outside the stepping motor  210  and outside two slits  251 ,  252  formed in the after-described plate magnetic shielding plate  250   b . On the other hand, the plate magnetic shielding plate  250   b  overlaps with the stepping motor  210  in the thickness direction to cover the stepping motor  210 . The plate magnetic shielding plate  250   b  overlaps with the winding stem  205  in the thickness direction to cover the winding stem  205 . 
     Although the plate magnetic shielding plate  250   b  is originally a bridge that supports a film solar cell disposed in a top surface of the plate magnetic shielding plate  250   b , this bridge also serves as a magnetic shielding plate. The slits  251 ,  252  intersecting with extended lines  216   a ,  216   b , respectively, are formed in portions (portions corresponding to extended lines) of the plate magnetic shielding plate  250   b . These portions cover the extended lines  216   a ,  216   b  in the longitudinal direction of a coil winding core  211   a  from both end portions  211   c ,  211   d  of the coil winding core  211   a  of a coil  211  of the stepping motor  210 . The ring magnetic shielding plate  250   a  and the plate magnetic shielding plate  250   b  are arranged to sandwich a not shown main plate in the thickness direction. In addition, the ring magnetic shielding plate  250   a  may contact the plate magnetic shielding plate  250   b.    
     When the movement  203  and the electronic timepiece  201  configured as described above are exposed by the external magnetic field that generates magnetic flows T 1 , T 2  toward the coil  211  from the directions of the extended lines  216   a ,  216   b  of the coil  211 , the magnetic flows T 1 , T 2  in the plate magnetic shielding plate  250   b  are blocked by the slits  251 ,  252  formed near the coil  211  from flowing in the coil  211 , and are changed to flows T 1   a , T 1   b , T 2   a , T 2   b  which are not directed toward the coil  211 . 
     Although the plate magnetic shielding plate  250   b  includes supporting portions  257   a ,  257   b  that support other components except for the stepping motor  210  as portions that receive the flows T 1   a , T 1   b , T 2   a , T 2   b  which are not directed toward the coil  211 , these portions that receive the magnetic flows T 1   a , T 1   b , T 2   a , T 2   b  are effectively used as the supporting portions  257   a ,  257   b.    
     As described above, according to the movement  203  of the electronic timepiece  201  and the electronic timepiece  201 , the magnetic flows T 1 , T 2  in the longitudinal direction of the coil  211  by which the stepping motors  210  are easily most affected are prevented or controlled from flowing in the stepping motor  210  covered by the plate magnetic shielding plate  250   b . It becomes difficult for the stepping motor  210  covered by the plate magnetic shielding plate  250   b  to be affected by the magnetic flows T 1 , T 2 . 
     The electronic timepiece  201  includes a configuration in which the stepping motor  210  is arranged such that the extended lines  216   a ,  216   b  of the coil winding core  211   a  become parallel or substantially parallel (hereinafter, simply substantially parallel) to the direction of the cutout  250   a   1  (direction connecting cutout  250   a   1  and center C of ring of ring magnetic shielding plate  250   a ) of the ring magnetic shielding plate  250   a  including, in a part thereof in the circumference direction, the cutout  250   a   1  through which the winding stem  205  is inserted. As described above, by disposing the stepping motor  210  such that the extended lines  216   a ,  216   b  of the coil winding core  211   a  become substantially parallel to the direction of the cutout  250   a   1  of the ring magnetic shielding plate  250   a , the magnetic shielding performance with the ring magnetic shielding plate  250   a  and the plate magnetic shielding plate  250   b  is further improved with respect to the stepping motor  210 . 
     Namely, as illustrated in  FIG. 6 , the magnetic flow T 1  substantially parallel to the coil winding core  211   a  generated by the external magnetic field flows in the ring magnetic shielding plate  250   a  in addition to the plate magnetic shielding plate  250   b . More specifically, a part of the magnetic flow T 1  is guided inside the ring magnetic shielding plate  250   a  from each of end portions  250   a   2 ,  250   a   3  of the ring magnetic shielding plate  250   a , that face each other via the cutout  250   a   1 . A magnetic flow T 11   a  guided inside the ring magnetic shielding plate  250   a  from the end portion  250   a   2  flows inside the ring magnetic shielding plate  250   a  in the clockwise direction, and a magnetic flow T 11   b  guided inside the ring magnetic shielding plate  250   a  from the end portion  250   a   3  flows inside the ring magnetic shielding plate  250   a  in the counterclockwise direction. 
     A part of the magnetic flow T 1  substantially parallel to the coil winding core  211   a , which is guided to the plate magnetic shielding plate  250   b  flows away from the coil winding core  211   a  by the slits  251 ,  252 , and a part of the magnetic flow T 1  which is not guided to the plate magnetic shielding plate  250   b  is guided to the ring magnetic shielding plate  250   a , and also flows away from the coil winding core  211   a . According to the movement  203  of the electronic timepiece  201  and the electronic timepiece  201 , the magnetic shielding performance to the stepping motor  210  can be further improved with respect to the magnetic flow T 1  substantially parallel to the coil winding core  211   a.    
     When the stepping motor  210  is arranged such that the direction of the cutout  250   a   1  of the ring magnetic shielding plate  250   a  becomes substantially parallel to the extended lines  216   a ,  216   b  of the coil winding core  211   a  (in  FIG. 6 , when cutout  250   a   1  of ring magnetic shielding plate  250   a  is formed in 12 o&#39;clock position (upper side of figure) or 6 o&#39;clock position (lower side of figure)), a part of the magnetic flow T 1  is guided inside the ring magnetic shielding plate  250   a , and becomes the flow T 11   a  in the clockwise direction and the flow T 11   b  in the counterclockwise direction inside the ring magnetic shielding plate  250   a.    
     However, when the cutout  250   a   1  is formed in the 12 o&#39;clock position, the magnetic flow T 11   a  in the clockwise direction is blocked by the cutout  250   a   1 , and flows from the cutout  250   a   1  to the plate magnetic shielding plate  250   b  to be the magnetic flow toward the coil winding core  211   a  which may affect the coil winding core  211   a . When the cutout  250   a   1  is formed in the 6 o&#39;clock position, the magnetic flow T 11   b  in the counterclockwise direction is blocked by the cutout  250   a   1 , and flows from the cutout  250   a   1  in the plate magnetic shielding plate  250   b  to be the magnetic flow toward the coil winding core  211   a , which may affect the coil winding core  211   a . In addition, the magnetic flow T 2  whose direction is opposite to that of the magnetic flow T 1  is also blocked, and flows similar to the above magnetic flow T 1 . 
     As described in details, by disposing the stepping motor  210  such that the extended lines  216   a ,  216   b  of the coil winding core  211   a  becomes substantially parallel to the direction of the cutout  250   a   1  of the ring magnetic shielding plate  250   a , the magnetic shielding performance to the stepping motor  210  by the ring magnetic shielding plate  250   a  and the plate magnetic shielding plate  250   b  is further improved to be better than that when the stepping motor  210  is arranged such that the extended lines  216   a ,  216   b  of the coil winding core  211   a  do not become substantially parallel to the direction of the cutout  250   a   1  of the ring magnetic shielding plate  250   a  (for example, stepping motor  210  is arranged such that extended lines  216   a ,  216   b  of coil winding core  211   a  become substantially orthogonal to direction of cutout  250   a   1  of ring magnetic shielding plate  250   a ). 
     According to the electronic timepiece and the movement of the present disclosure, the stepping motor is not limited to be arranged such that the extended lines of the coil winding core become parallel to the direction of the cutout of the ring magnetic shielding plate as described above. 
     Another Modified Example 
       FIGS. 7, 8, 9, 10, 11  are schematic views illustrating variations (Modified Examples 3 to 7) of arrangement of two stepping motors  310 ,  320  and formation of slits  351 ,  352 ,  353  in a magnetic shielding plate  350  when the movement of the electronic timepiece as another embodiment of the present disclosure includes the two stepping motors  310 ,  320 . 
     When the coils  311 ,  321  of the two stepping motors  310 ,  320  are arranged in substantial parallel ( FIGS. 7, 8, 9 ), the slits  351 ,  352  as the magnetic flow changing portions of the magnetic shielding plate  350  may be shared by the two coils  311 ,  321 , respectively, as illustrated in  FIGS. 7, 8 , or the slit  352  between the two coils  311 ,  321  may be only shared, as illustrated in  FIG. 9 . 
     More specifically, as illustrated in  FIGS. 7, 8 , the slit  351  is formed to intersect with an extended line  316   a  of the coil  311  of the stepping motor  310  in the longitudinal direction and an extended line  326   a  of the coil  321  of the stepping motor  320  in the longitudinal direction while the slit  352  is formed to intersect with an extended line  316   b  of the coil  311  of the stepping motor  310  in the longitudinal direction and an extended line  326   b  of the coil  321  of the stepping motor  320  in the longitudinal direction. 
     As illustrated in  FIG. 9 , the slit  351  is formed to intersect with the extended line  316   a  of the coil  311  of the stepping motor  310  in the longitudinal direction, the slit  352  is formed to intersect with the extended line  316   b  of the coil  311  of the stepping motor  310  in the longitudinal direction and the extended line  326   a  of the coil  321  of the stepping motor  320  in the longitudinal direction, and the slit  353  is formed to intersect with the extended line  326   b  of the coil  321  of the stepping motor  320  in the longitudinal direction. 
     On the other hand, when both of the coils  311 ,  312  of the two stepping motors  310 ,  320  are arranged to be substantially orthogonal to each other ( FIG. 10 ), two slits are formed with respect to each of the stepping motors  310 ,  320 . More specifically, the slit  351  is formed to intersect with the extended line  316   a  of the coil  311  of the stepping motor  310  in the longitudinal direction, the slit  352  is formed to intersect with the extended line  316   b  of the coil  311  of the stepping motor  310  in the longitudinal direction, the slit  353  is formed to intersect with the extended line  326   a  of the coil  321  of the stepping motor  320  in the longitudinal direction, and a slit  354  is formed to intersect with the extended line  326   b  of the coil  321  of the stepping motor  320  in the longitudinal direction. 
     However, when the extended line  326   b  of the coil  321  of the stepping motor  320  in the longitudinal direction is arranged to intersect with the coil  311  of the stepping motor  310 , a hole through which the coil  311  is inserted is formed in the magnetic shielding plate  350 , and the hole can be therefore used as the slit  354 . 
     As illustrated in  FIG. 11 , when the stepping motor  310  includes two coils  311 A,  311 B, the slit  351  is formed to intersect with the extended line  316   a  of the coil  311 A in the longitudinal direction and the extended line  316   c  of the coil  311 B in the longitudinal direction, and the slit  352  is formed to interest with the extended line  316   b  of the coil  311 A in the longitudinal direction and an extended line  316   d  of the coil  311 B in the longitudinal direction. 
     When a magnetic member, in particular a large magnetic member such as a battery is arranged near the stepping motor, a magnetic flow changing portion (for example, slit) may be provided in a portion of the large magnetic member, which is opposite to a portion near the stepping motor. The magnetic flow changing portion can prevent the external magnetism to be guided by the large magnetic member, and thus prevent the external magnetism from flowing in the neighboring stepping motor. 
     When a battery  380  is arranged instead of the stepping motor  320  with the configuration illustrated in  FIG. 7  (see  FIG. 12 ), for example, the right slit  352  of the battery  380  operates as the magnetic flow changing portion that prevents the external magnetism to be guided by the battery  380 . This configuration is an example in which the battery  380  is arranged between the stepping motor  320  and the slit  352 .