JP2004191362A - Antenna structure and radio wave correcting clock - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an antenna structure having good radio wave receiving performance and free from restrictions in material and design, and a radio wave utilizing clock using the antenna structure. <P>SOLUTION: The antenna structure 2 is shown which is arranged in a clock wherein at least either of a side part 4 and a rear rid part 3 is made of a metal, can receive radio waves, and has an L value of 1,600 mH or less. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to an antenna structure and a radio-controlled timepiece using the antenna structure. More particularly, the present invention relates to a resonance antenna, and more particularly, to a resonance antenna, even when the antenna structure is arranged near a metal object. The present invention relates to an antenna structure configured so as not to lower the radio wave reception performance of the structure, and a radio-controlled timepiece using the antenna structure.

  In recent years, many radio-controlled timepieces have been commercialized which receive a long-wave standard radio wave with a time code and automatically adjust the time of a watch in use to the time of the standard time.

  In a radio-controlled timepiece, the receiving performance is determined by the antenna characteristics and the receiving circuit characteristics.

  At present, the lower limit of the input signal of the receiving circuit or the receiving IC is about 1 μV in signal amplitude, and in order to obtain practical receiving performance, the receiving antenna has an electric field strength (radio wave intensity) of 40 to 50 dBμV / m. In this case, an output having a signal amplitude of about 1 μV must be obtained.

  Therefore, when there is a size restriction, it is common to use a resonance type receiving antenna that can increase the signal output.

  Further, as a type of the receiving antenna, a bar antenna having a conductive wire wound around a magnetic core is generally used because the wavelength of a radio wave is long.

  In such a receiving antenna, the output of the receiving antenna is roughly proportional to the size of the receiving antenna, so that it cannot be reduced so much to obtain practical receiving performance. Performance and placement are issues.

  Further, the output of the receiving antenna is extremely reduced when housed in a metal exterior.

  Therefore, in a wristwatch, in order to use radio waves, a component configuration or design completely different from a conventional watch component configuration or design is required, and consideration must be given not to hinder reception performance.

  In a wristwatch, small size, thinness, easy portability, freedom of design, and texture (luxury) are important issues, and a built-in antenna type and metal exterior are desired.

  In the case of a conventional radio-controlled timepiece, a method of externally mounting an antenna or a method of incorporating an antenna is mainly used.

  When the material of the back cover / side of the watch is metal, the receiving antenna is generally provided as an exterior.

  In this case, since the case of the receiving antenna is made of a non-metal such as plastic so as not to deteriorate the receiving performance, the receiving antenna case has a large protruding shape, which impairs small size, thinness, easy portability and remarkably impairs the degree of freedom in design.

  In the case of a system with a built-in receiving antenna, ceramics or plastics are used as the material of the watch exterior (back cover / side) in order not to reduce the receiving performance. In addition, the portability and portability are impaired, and the design restrictions are increased.

  In addition, the appearance of the wristwatch is low.

Therefore, conventionally, for example, Japanese Utility Model Laid-Open No. 2-126408 (
), A metal antenna is arranged in a leather band of a watch. Also, the applicant of the present application has disclosed Japanese Utility Model Laid-Open No. 5-81787 ( ), An antenna with a coil wound around the core is placed between the dial and the windshield, separated from the metal case body that blocks radio waves, and has a unique design, or Published WO 95/27928 ( 2) discloses a wristwatch having a configuration in which an antenna is attached to a side of a watch case of the wristwatch. Further, European Patent Publication No. 0382130 ( ), An antenna is arranged on the upper surface of the case in a ring shape, for example. However, in the conventional configuration in which the antenna is arranged in the band, since the antenna is built in the band, it is necessary to establish conduction with the electronic device main body, and it is possible to give sufficient flexibility to the joint between the two. Absent.

  Furthermore, a metal band that blocks radio waves cannot be used, and a watch band such as a rubber band for connection must be used, and there are restrictions in terms of material and design.

  In the case of a configuration in which an antenna is arranged on the upper surface or the side surface of a wristwatch, since the antenna is separated from the metal part of the watch main body, the thickness or size of the entire watch is increased, or design restrictions are imposed. There is a problem.

Further, European Patent Publication No. 0382130 (hereinafter, referred to as Patent Document 3) in which an antenna is arranged in a ring shape on the upper surface of a case
In the case of (1), if metal exists inside the ring, reception cannot be performed, so that there is a problem that the antenna must be separated from the clock in practical use. Further, Japanese Patent Application Laid-Open No. H11-64547 ( ) Discloses a wristwatch in which a coil is arranged in a recess provided in a peripheral portion of a circuit board and a core is arranged in a curved shape along the circumferential direction of the circuit board, but the manufacturing process is complicated. In addition, there is a problem that the assembling operation in the manufacturing process becomes complicated. On the other hand, JP-A-2001-33571 ( ) Or JP-A-2001-30524 ( ) And the like, the windshield and back cover of the wristwatch are made of a non-metallic material such as glass or ceramic, and the middle part is made of a conventional metal material, and sufficient radio waves reach the antenna. A wristwatch configured to do so is shown. That is, in the above-described conventional example, the output of the receiving antenna is based on the fact that the output is extremely reduced when the antenna is housed in a metal exterior. The purpose is to use a high-quality metal side.

  However, in the above-described conventional example, there is a problem that the thickness of the timepiece is increased because glass or ceramics is used.

  Therefore, conventionally, a large-sized high-sensitivity antenna structure is used, or it can be used only in an area where the electric field strength of radio waves is strong. In addition, the manufacturing cost of the antenna structure is inevitably high.

  Of course, in a wristwatch with such a configuration, even if the arrival of radio waves to the antenna can be surely ensured, it is as if the back cover is made of a metal material with a thin metallic plating. Although it gives the user a variety of impressions, there is a problem in that the appearance is lacking in weight or texture and the image as a luxury product is impaired.

  Furthermore, since the receiving antenna is built in the metal side, the output of the antenna is reduced and the receiving performance is reduced.

  For this reason, a radio-controlled timepiece with a completely metallic exterior having a high-quality feel has not been realized until now.

  In order to solve such a problem of the prior art, the present applicant has already disclosed in Japanese Patent Application No. 2002-297095 that an antenna is disposed inside a watch case having a metal side or a metal cover. As a result, it is found that there is a problem that the value is reduced and the output from the antenna structure is reduced and the reception performance is significantly reduced, and by using an antenna having a special structure to solve the problem, A technical configuration has been proposed in which a decrease in the Q value of the antenna structure is suppressed as much as possible to prevent a decrease in the reception performance of the antenna.

  However, in the method for specifying the structure of the antenna described above, it has been found that there is a limit to the improvement of the receiving performance in the antenna structure. It has been found that the above problems are further improved by adding specific performance to the structure.

JP-A-2-126408 JP-A-5-81787 International Publication WO95 / 27928 European Patent Publication No. 0382130 JP-A-11-64547 JP 2001-33571 A JP 2001-30524 A

  Therefore, the present invention solves the above-mentioned conventional problems, that is, an antenna structure having good radio wave reception performance and not subject to material restrictions and design restrictions, and a radio wave correction using the antenna structure. It is intended to provide a wristwatch.

  Further, when the present invention is applied to a wristwatch, it is another object of the present invention to provide an antenna device for a wristwatch that, in addition to the above objects, prevents the wristwatch from increasing in thickness and bulky and has a good feeling of being worn on an arm. I do.

  The present invention employs the following basic technical configuration to achieve the above object. That is, as a first aspect of the present invention, there is provided an antenna structure capable of receiving radio waves arranged in a timepiece in which at least one of a side portion and a back cover portion is made of metal, Is an antenna structure having an L value of 1600 mH or less, and according to a second aspect of the present invention, the antenna is disposed in a timepiece in which at least one of a side portion and a back cover portion is made of metal. An antenna structure capable of receiving an electric wave, wherein the winding resistance of the antenna is 1 KΩ or less.

  Further, as a third aspect of the present invention, there is provided an antenna structure capable of receiving a radio wave arranged in a timepiece in which at least one of a side portion and a back cover portion is made of metal, wherein the antenna is wound. The antenna structure has 400 or more lines.

  According to a fourth aspect of the present invention, there is provided an antenna structure for receiving a radio wave, wherein the antenna structure has any one of the above-described first to third aspects and an external radio wave. Has a structure of a magnetic path in which a magnetic flux generated by resonance is hardly leaked to the outside, and the magnetic path has a coil winding portion where at least one conductor is wound and a coil is formed. And a non-coil-wound portion where the conductor is not wound.

  Further, as a fifth aspect of the present invention, there is provided a radio-controlled timepiece in which at least one of a side portion and a back cover is made of metal, and an antenna built in the radio-controlled timepiece. Is a radio-controlled timepiece constituted by any of the antenna structures shown in each of the above-described embodiments, and a reference signal generating means for outputting a reference signal; and a timekeeping means for outputting timing information based on the reference signal. Display means for displaying the time based on the time information; receiving means for receiving a standard radio wave having reference time information; and correcting the output time information of the time means based on a signal received from the receiving means. In the radio-controlled timepiece, the radio-controlled timepiece has at least one of a side portion and a back cover made of metal, and the receiving means includes any one of the antenna structures described in the above aspects. so It is a radio-controlled timepiece that have been made.

  Since the antenna structure of the present invention and the wristwatch having the antenna structure adopt the above-described technical configuration, the structure, material, design, etc. of the conventional timepiece can be simplified without drastic change. Adopted antenna structure with configuration, good reception performance, the size and thickness of the wristwatch itself is not different from the conventional one, the design flexibility, the antenna structure using a high quality exterior In addition, a radio-controlled timepiece using the antenna structure can be easily obtained.

  Hereinafter, specific examples of an antenna structure according to the present invention and a radio-controlled timepiece using the antenna structure will be described in detail with reference to the drawings.

  Hereinafter, the configuration of a specific example of the antenna structure according to the present invention and a radio-controlled timepiece using the antenna structure will be described in detail with reference to the drawings.

  That is, FIG. 1 is a schematic plan view showing a specific example of the antenna structure 2 according to the present invention, in which at least one of the side part 4 and the back cover part 3 is made of metal. The antenna structure 2 that can receive a radio wave disposed therein and has an L value of 1600 mH or less is shown.

  That is, in the above-described conventional example, when the antenna is inserted and arranged in a metal exterior part such as a metal side or a lid, the antenna receives radio waves, and a magnetic flux oscillated by resonating is arranged around the antenna. Interaction with the metal sheath, specifically, energy loss increases due to eddy loss, and the resonance phenomenon (magnetic force → power → magnetic force →...) Generated by the antenna is hindered by the metal sheath. Specifically, the magnetic force generated by the resonance phenomenon is attracted to the metal part, causing an eddy current phenomenon, and most of the magnetic force is consumed (due to the effect of iron loss). As a result, the gain and Q value of the antenna are reduced. There has been a problem in the practical use of a radio-controlled timepiece in which an antenna is arranged inside a metal exterior, because of a drastic decrease.

  The gain of an antenna is composed of two parts: the gain due to the magnetic flux of the transmitted signal and the output due to the magnetic flux increased by the resonance phenomenon of the antenna. Generally, the main component of the output of the antenna consists of the gain due to the magnetic flux increased by the resonance phenomenon of the antenna. I have.

  When the antenna is inserted into the metal sheath, the resonance phenomenon of the antenna is hindered and the Q value is greatly reduced, so that the gain is also greatly reduced.

  In other words, when a metal object is not present in the vicinity, most of the gain of the antenna is almost the gain obtained by the above-described resonance phenomenon, and when the winding resistance (copper loss) of the antenna increases, resonance occurs. Since this hinders the phenomenon and causes a decrease in gain (Q value), it has not been possible to extremely increase the number of turns or make the winding thin.

  On the other hand, when the antenna is placed in a metal exterior, the Q value is greatly reduced and the gain is also greatly reduced because the effect of iron loss (metal exterior) is large.

  Therefore, the inventor of the present application changed the conventional idea, and based on the premise that when the antenna structure is used inside a metal exterior, it is inevitable that the Q value is inevitable, The present inventors have intensively studied a method for improving the gain of the structure.

  That is, in the present invention, when the antenna structure is inserted and arranged in the metal exterior part, gain is not obtained by the amplification factor due to the Q value (resonance phenomenon) as in the related art, but by the magnetic flux of the transmission signal. It is based on a technical idea that has been gained as a result of pursuing how to maximize the gain obtained.

  In order to confirm the above technical idea, the present inventors first measured the relationship between the L value (mH) of a predetermined antenna structure as shown in FIG. 2 and the gain (dB) of the antenna structure. An experiment was performed.

  The antenna used was an antenna as shown in FIG. 18, and the material of the antenna core was an amorphous magnetic material.

  That is, FIG. 18 is a view showing a structure of one specific example in the case where the magnetic path 6 has a structure in which a closed magnetic path is not formed in the present invention, and the basic configuration is the same as that of FIG. Although it is used, the antenna core portion 9 'of the non-coil winding portion in FIG. 9 is omitted.

  A specific example of the method for measuring the gain and Q value of the antenna according to the present invention is as follows.

  Here, a specific example of a method for measuring the gain and Q value of the antenna according to the present invention will be described.

  That is, a network analyzer (4195A) manufactured by Hewlett-Packard Company (HP), a high-frequency probe (85024A) manufactured by Hewlett-Packard Company (HP), and a transmission antenna (Test Loop 75Q, VQ-085F) of National (Matsushita Electric). Are connected as shown in FIG. 16 to form an antenna evaluation circuit, and the high-frequency probe (85024A) for connecting the antenna to be measured near the transmitting antenna (test loop 75Q, VQ-085F) and the sample supporter. After setting a predetermined antenna to be measured on the sample supporter, a predetermined radio wave is transmitted from the transmitting antenna (test loop 75Q, VQ-085F), and the output of the antenna to be measured is compared with the high-frequency probe ( 85024A) and the network analyzer Those configured so as to a predetermined antenna rated at 4195A).

  In the above-described evaluation device, the distance between the measured antenna structure 2 and the transmission antenna (test loop 75Q, VQ-085F) is set at a position 11 cm away from the lower end of the transmission loop antenna as shown in FIG. At the same time as the receiving antenna was installed, and at the same time, the measured antenna structure 2 was brought into contact with the metal sheath 3 to perform the measurement.

  Further, in the above specific example, the frequency of the radio wave transmitted from the transmission antenna (test loop 75Q, VQ-085F) is in the range of 77.5 ± 20 KHz when measuring the resonance antenna for 77.5 KHz. The measurement was carried out while changing.

  A method for measuring the gain and the Q value of the resonance antenna for 77.5 KHz with the above-described measuring device will be described with reference to FIG.

  That is, the transmitting antenna (test loop 75Q, VQ-085F) is swept from the network analyzer (4195A) to the transmitting antenna (test loop 75Q, VQ-085F) at a constant output in a frequency range of 77.5 ± 20 KHz, and the output of the antenna 2 to be measured is output to the high frequency probe (85024A ) To obtain an output result as shown in FIG.

  Here, the gain of the antenna is represented by the ratio of the amplitude of the input voltage to the transmitting antenna to the amplitude of the output voltage of the antenna under test. In FIG. 7, the frequency with the highest antenna output is the resonance frequency (f0), and the antenna output is The value of the above ratio at the highest point was defined as the antenna gain.

  Further, using the equation of Q value = resonance frequency f0 ÷ (f2−f1), f1 and f2 were obtained from the measurement results, and the Q value was calculated.

  In FIG. 2, a graph A shows a relationship between an L value and a gain (dB) when a 77.5 KHz radio wave is received in a state where a predetermined antenna structure is not inserted into a metal exterior part. Graph B shows the relationship between the L value and the gain (dB) when a radio wave of 77.5 KHz was received in a state where the antenna structure was inserted into the metal exterior part.

  In this experiment, a winding was wound around a normal linear core portion by a normal method, and the change in the L value was adjusted by changing the number of windings.

  As can be seen from FIG. 2, in the antenna structure not inserted in the metal sheath, the gain increases as the L value increases, but gradually saturates when the L value exceeds about 10 mH. However, regarding the antenna structure inserted into the metal sheath, the saturation phenomenon as described above does not occur, and it can be seen that the gain linearly increases in proportion to the increase of the L value.

  As a result of further studies, the present inventors have found that, from the results of FIG. 2, in the antenna structure 2 used in the metal exterior part, the gain linearly increases as the L value increases. It is determined that it is desirable to increase the L value by increasing the number of turns of the wire.

  However, if the number of turns of the antenna is increased, the capacity of the antenna itself is increased, so that a restriction is imposed on the resonance point of the antenna, so that the upper limit is necessarily determined.

  The line-to-line capacity of the antenna is determined by the number of windings and the type of windings, but assuming a realistic situation, the thickness of the watch is 10 mm, the winding width of the antenna core is 12 mm in order to fit in a 30 mm diameter watch, The thickness of the antenna is 5.5 mm assuming the thickness of the exterior and the thickness of the ground plane of the movement, and sufficient performance as a radio controlled watch is obtained when the core thickness is 3 mm, at which sufficient strength of an inexpensive ferrite core is obtained. In order to wind the number of windings of 1400T, a conductor diameter of 100 μm and a conductor diameter of 110 μm can minimize the resistance value most.

  According to these conditions, an antenna was formed by winding a wire having a winding width of 12 mm, a conductor diameter of 100 μm, and a conductor diameter of 110 μm using a ferrite core of φ3 mm and a length of 50 mm, and an experiment was performed to determine the line capacitance of the antenna. The characteristics of the frequency and the L value are as shown in FIG. 20, the change of the L value with respect to the change of the frequency is shown in a graph P, and the change of the Q value with the change of the frequency is shown in a graph Q.

  As understood from FIG. 20, a 264.9 pF capacitor is connected in parallel to the antenna to tune to about 35 KHz where the L value of the antenna is stable, and tuning is performed. As a result, the resonance frequency becomes 34.4 KHz. When the L value at this resonance frequency is calculated from FIG. 20, it becomes 78.27205 mH, and when the line capacitance of the antenna is calculated from the above values, it becomes 8.852 pF. At least about 10 pF inevitably generates line capacitance. Conceivable.

  Further, since the lowest frequency band is 40 KHz, the L value of the antenna structure 2 is calculated from the formula f = 1 / 2π√LC based on this capacity and the above frequency. It is about 1600 mH, so it is desirable to use the L value at 1600 mH or less.

  Actually, when the parasitic capacitance of the mounting substrate and the receiving IC is included in addition to the winding capacitance of the antenna, the parasitic is considered to be about 20 pF. In such a situation, the L value is 792 to 800 mH. Since it is determined, it is desirable to use the antenna structure 1 whose L value is 800 mH or less.

  Further, when realistically considered, the highest existing frequency band among the used frequency bands is 77.5 KHz (Germany). When the L value of the antenna structure 2 is calculated based on the above capacitance and frequency, it is about 211 to 220 mH, and it is desirable to use the antenna structure 1 having the L value of 220 mH or less.

  Note that the lower limit of the L value in the antenna structure 2 according to the present invention is desirably about 20 mH.

  As a result of field surveys on electric field strength in Japan, Germany, etc. that transmit standard radio waves, it is necessary to receive at least 50 dBμV / m electric field strength in order for radio clocks to be sufficiently received in all regions of the transmitting country. is necessary.

  The minimum gain required for the antenna depends on the performance of the receiving IC. However, considering the current performance of the receiving IC, the antenna gain is required to be at least -51 dB. Considering the resonance frequency variation due to the variation of the C value, it is necessary to be -49 dB or more, more preferably -47 dB or more in consideration of the performance variation of the receiving IC.

  Therefore, from FIG. 2, the lower limit of the L value is also 20 mH or more corresponding to the antenna gain of −51 dB, preferably 25 mH or more corresponding to the antenna gain of −50 dB, more preferably 33 mH corresponding to the antenna gain of −49 dB. As described above, it is most preferable that 40 mH or more corresponding to -47 dB of the antenna gain is desirable.

  The value of the L value determined to be preferable in the present invention is an extremely unique value in consideration of the fact that the L value of the antenna structure in the conventional radio-controlled timepiece is at most 2 to 13 mH. The thing is understood.

  Next, the present inventors examined the relationship between the number of turns (T) of the windings and the gain (dB) in the antenna structure, and the results are shown in FIG.

  The antenna used was an antenna as shown in FIG. 18, and the material of the antenna core was an amorphous magnetic material.

  The method for measuring the gain and Q value of the antenna according to the present invention is as described above.

  That is, in FIG. 3, similarly to the experiment of FIG. 2, the winding of the antenna structure 2 when receiving a radio wave of 77.5 KHz without inserting a predetermined antenna structure into the metal exterior part. The relationship between the number (T) and the gain (dB) is shown in a graph C, and the number of windings (T) when receiving an electric wave of 77.5 KHz in a state where the antenna structure having the same structure is inserted in the metal exterior part. The relationship between the gain and the gain (dB) is shown in graph D.

  As can be seen from FIG. 3, in the antenna structure not inserted into the metal sheath, the gain increases as the number of windings (T) increases, but the number of windings (T) is 1000. However, the saturation does not occur as described above for the antenna structure inserted into the metal sheath, and the gain increases linearly in proportion to the increase in the number of windings (T). I understand.

  Therefore, according to the present invention, in the radio-controlled timepiece in which at least one of the side portion of the exterior portion and the lid portion is made of metal or the radio-controlled timepiece in which the side portion and the lid portion of the exterior portion are made of metal, the antenna structure It is determined that the number of windings (T) of the body 2 is desirably 1000 T or more.

In the case of adopting the antenna structure composed of the main magnetic path and the sub magnetic path of the first embodiment, 400T is desirable.
Also, the antenna gain is required to be at least -51 dB or more. In FIG. 3, since 1400T corresponds to -51 dB, in the radio-controlled timepiece in which at least one of the side and the lid of the exterior is made of metal. Is determined to be effective when the number of windings (T) of the antenna structure 2 is 1400 or more.

  Further, as can be understood from FIG. 3, when the antenna structure 2 is used alone without entering the metal exterior part, when the number of windings (T) is 1500 or more, the rate of increase in gain is reduced. Although the antenna structure 2 is saturated, but the antenna structure 2 is arranged in the metal sheath, the gain linearly increases even when the number of windings (T) is 1500 or more. In a radio-controlled timepiece in which at least one of the part and the cover is made of metal, it is determined that it is more effective that the number of windings (T) of the antenna structure 2 is 1500 or more.

  On the other hand, as the number of windings (T) of the antenna increases, the resistance of the windings of the antenna increases. Therefore, the upper limit of the number of windings (T) is also limited.

  Then, as shown in FIG. 4, the inventors of the present invention set a case where the winding resistance (Ω) and the gain of the antenna structure 2 and the winding resistance (Ω) and the antenna structure are brought close to the metal exterior part. An experiment was conducted to examine the relationship between the gain difference in the case where no gain was applied and the gain difference.

  That is, in FIG. 4, similarly to the experiment of FIG. 2, the winding of the antenna structure 2 when receiving a radio wave of 77.5 KHz without inserting the predetermined antenna structure into the metal exterior part. The relationship between the resistance (Ω) and the gain (dB) is shown in a graph E, and the winding resistance (Ω) when receiving the radio wave of 77.5 KHz with the antenna structure having the same structure inserted in the metal exterior part. The relationship between the gain and the gain (dB) is shown in graph F.

  Also, the relationship between the winding resistance (Ω) and gain of the antenna structure 2 and the gain difference between the case where the winding resistance (Ω) is close to the metal exterior and the case where the antenna structure is not close to the metal exterior. Is shown in graph G.

  In the experiment shown in FIG. 4, the adjustment of the winding resistance (Ω) was performed by appropriately changing the resistance as shown in FIG. 4 (B).

  As can be understood from FIG. 4 (A), the antenna structure 2 can be used either alone without the metal sheath or when the antenna structure 2 is arranged inside the metal sheath. It is shown that the gain decreases as the winding resistance (Ω) increases.

  Looking at the graph G showing the gain difference between the graphs E and F, when the value of the winding resistance (Ω) becomes 1 KΩ or more, the antenna structure 2 is not used with a metal sheath. It can be understood that there is no change in the difference in gain when used inside the metal casing, and the gain difference is constant around about 3 to 4 dB.

  This is because, when a metal object having conductivity is arranged near an antenna for receiving a radio wave or in contact with the antenna in the related art, the radio wave is absorbed by the metal object. Since the radio wave does not reach the antenna, the resonance output of the antenna is reduced. For example, it was thought that the Q value was reduced. In fact, even if the grasp of the problem in question is an error and there is a metal object having conductivity near the antenna or in contact with the antenna, the antenna is In the case where the radio wave has substantially arrived and is non-resonant, the flow of magnetic flux due to the external radio wave trying to enter the watch from the outside is somewhat attenuated (for example, about 3 dB). Said without obstacles The fact that reaching the antenna, but could be confirmed, consistent with this fact.

  Also, in FIG. 19, similarly to the experiment of FIG. 4, the winding resistance of the antenna structure 2 when receiving a radio wave of 77.5 KHz without inserting a predetermined antenna structure into the metal sheath ( The relationship between the Q value and the Q value is shown in a graph L, and the winding resistance (Ω) of the antenna structure 2 when receiving an electric wave of 77.5 KHz in a state where the antenna structure having the same structure is inserted in the metal exterior part is shown. ) And the Q value are shown in graph N.

  In the experiment in FIG. 19, the adjustment of the winding resistance (Ω) value of the antenna was carried out by appropriately changing the arrangement in the same manner as in FIG.

  As understood from FIG. 19, as the winding resistance (Ω) of the antenna increases, the use of the antenna structure 2 alone without a metal sheath greatly reduces the Q value. When the antenna structure 2 is arranged in a metal sheath, the Q value is stable at around 5 up to the winding resistance of the antenna of 100Ω. It is considered that the number of lines can be increased, the L value can be increased, and the antenna gain can be improved.

  From this result, if the value of the winding resistance (Ω) of the antenna is 1 KΩ or less, the contribution of the effect to the gain of the antenna structure 2 used in the metal sheath does not use the metal sheath. Since it is considered that the contribution to the effect on the gain in the case is larger, the winding resistance (Ω) of the antenna structure 2 in the present invention is desirably 1 KΩ or less.

  Generally, the thickness of the timepiece is considered to be about 10 mm, the width of the winding of the antenna is 20 mm, the thickness of the winding core is 1 mm, the thickness of the winding is a conductor diameter of 60 μm, a conductor diameter of 65 μm, and the winding resistance of the antenna is 1 KΩ. , The limit of the number of windings of the winding is 25000T.

  Assuming a realistic situation, the thickness of the watch is 10 mm, the winding width of the antenna core is 12 mm in terms of space to accommodate the watch in a diameter of 30 mm, and the thickness of the antenna is 5 mm assuming the thickness of the exterior and the thickness of the ground plate of the movement. In order to make the winding resistance of the antenna about 1 KΩ in this space, the number of windings which can be wound most with a conductor diameter of 45 μm and a conductor diameter of 50 μm is 12000T.

  More preferably, considering the strength of the antenna of the inexpensive ferrite core, the winding core thickness is ideally 2 mm. In order to make the winding resistance of the antenna about 1 KΩ in this space, the conductor diameter is 45 μm and the conductor diameter is 50 μm. The maximum number of windings that can be wound is 9000T.

  More preferably, considering the strength of an inexpensive ferrite core antenna as a watch, the winding core thickness is ideally 3 mm. In order to reduce the winding resistance to about 1 KΩ in this space, the conductor diameter is 45 μm, The number of windings that can be wound most most with a diameter of 50 μm is 7000T.

  More specifically, the number of windings in the data of FIG. 2 is replaced by the winding resistance value of the sample, and as shown in FIG. 5, which is combined with the data of FIG. Graph H shows the relationship between the winding resistance (Ω) and the gain (dB) of the antenna structure 2 when receiving a radio wave of 77.5 KHz without inserting the antenna structure. Graph I shows the relationship between the winding resistance (Ω) and the gain (dB) when a 77.5 KHz radio wave was received in a state where the antenna was inserted into the section.

  These graphs H and I are substantially the same as graph E of FIG.

  On the other hand, the graph J in FIG. 5 shows the case of the antenna structure having the same structure as described above, in which the number of turns (T) is changed to 1000 to 2000 T and the state is shown in FIG. It shows the relationship between the winding resistance (Ω) and the gain (dB) when receiving a 5 KHz radio wave, and shows that the gain increases as the winding resistance (the number of windings) increases.

  Graph K is an approximate curve of graph J.

  On the other hand, the graph M shows the ratio of the gain that decreases as the winding resistance (Ω) increases, and increases as the winding resistance J increases as the number of windings (T) increases, as shown by the above graph I. 6 is a graph showing a balance with a gain to be performed.

  As is clear from the graph M of FIG. 5, it can be understood that the balance between the increase and the decrease of the gain is saturated as the winding resistance (Ω) becomes higher than around 396Ω, and therefore, the winding is reduced. It can be seen that no effect is obtained even if the winding is performed so that the wire resistance (Ω) becomes 400Ω or more.

  Therefore, the winding resistance (Ω) of the antenna structure 2 according to the present invention is desirably 400Ω or less.

  Further, in the present invention, it is considered that in the case 2 where a metal sheath is used, it is considered that the most efficient method is to use the antenna structure 2 in a region where the gain of the antenna structure 2 is high and the change is small. As can be understood from the graph F of FIG. 4, it is considered that it is desirable to use the antenna structure 2 in a state where the winding resistance (Ω) is 100Ω or less.

  The lower limit of the winding resistance (Ω) in the antenna structure 2 according to the present invention is desirably about 18Ω.

  That is, assuming that the minimum gain required for the antenna is -51 dB, the number of windings is 1400 T from FIG. 3, and as a practical assumption, the thickness of the watch core is 10 mm and the space of the antenna core is enough to accommodate the 30 mm diameter watch. The winding width is 12 mm, the thickness of the antenna is 5.5 mm assuming the outer thickness and the thickness of the ground plane of the movement, the winding core thickness is 1 mm, the conductor diameter is 130 μm to secure the number of windings of 1400 T in this space, and the conductor is With a diameter of 140 μm, the resistance can be minimized, and the value is 18Ω.

  Preferably, considering the strength of the antenna of the inexpensive ferrite core, the winding core thickness is 2 mm, and in order to secure the number of windings of 1400T in this space, the conductor diameter of 110 μm and the conductor diameter of 120 μm can minimize the resistance value, Its value is 27.6Ω.

  More preferably, assuming that the minimum gain required for the antenna is -50 dB, the number of windings is 1500 T, the conductor diameter is 110 μm, and the conductor diameter is 120 μm, and the resistance can be minimized, and the value is 30Ω.

  More preferably, assuming that the minimum gain required for the antenna is -49 dB, the number of windings is 1650 T, the conductor diameter is 100 μm, and the conductor diameter is 110 μm, and the resistance can be minimized, and the value is 38Ω.

  Most preferably, when the minimum gain required for the antenna is considered to be -47 dB, the number of windings is 1900T, and the conductor diameter of 95 μm and the conductor diameter of 105 μm can minimize the resistance value to 53Ω.

  Most preferably, considering the strength of an inexpensive ferrite core as a timepiece, considering the strength of the antenna, the winding core thickness is 3 mm, and in order to secure the number of windings of 1400 T to obtain the minimum antenna gain in this space, use a conductor. A diameter of 100 μm and a conductor diameter of 110 μm can minimize the resistance value, and the value is 41.6Ω.

  Incidentally, the winding resistance (Ω) of the antenna of the antenna structure in the conventional radio-controlled timepiece is at most about 3 to 20Ω, and the winding resistance (Ω) of the antenna in the present invention is the conventional resistance. It uses an antenna winding resistance (Ω) that is significantly higher than the level.

  From the above experimental results, according to the present invention, when the antenna structure 2 is arranged in the metal exterior part, Q is increased even if the winding resistance (copper loss) of the antenna of the antenna structure increases. The decrease in the value is very small. In other words, if the number of turns is the same even if the wire diameter is small, the change in the Q value and the gain G is small.

  On the other hand, the gain of the antenna of the antenna structure 2 is improved by increasing the number of turns.

  As a result, when the antenna structure is arranged in a metal sheath, it is possible to improve the gain by designing the winding to be thin and increasing the number of turns.

  Further, in a conventional mode in which the antenna structure 2 is not inserted into the metal exterior portion, when the diameter of the winding is large, for example, a winding having a diameter of 0.1 mmφ and a low resistance value is used. When using a winding having a smaller winding diameter, for example, the winding diameter is better than using a winding having a high resistance value with a winding diameter of 0.06 mmφ, but as in the present invention, In the case where the antenna structure 2 is disposed in the metal exterior part, no difference in gain characteristics is observed.

  Therefore, in the present invention, it is desirable to configure the antenna structure 2 using a thin winding, thereby making it possible to form the antenna structure 2 having a smaller size.

  Therefore, as another aspect of the antenna structure according to the present invention, the winding has a wire diameter of 0.1 mmφ or less, preferably 0.06 mmφ, and most preferably 0.045 mmφ. preferable.

  The above-described antenna structure 2 according to the present invention is based on a shape in which the winding is wound around a normal linear antenna core portion by a predetermined number of turns (T). Is not limited to this, and can be applied to an antenna structure having any form. In particular, the structure is disclosed in Japanese Patent Application No. 2002-297095 filed earlier by the present applicant. It is desirable to apply to the configuration of the antenna structure.

  That is, FIG. 6 is a diagram showing one specific configuration of the antenna structure 2 for receiving the constituent radio waves disclosed in Japanese Patent Application No. 2002-297095. The magnetic path 6 is capable of receiving, but has a structure of a magnetic path in which the magnetic flux generated in resonance is hardly leaked to the outside. The magnetic path 6 includes a coil winding portion 21 in which a conductor is wound and a coil is formed, and a coil in which the conductor is wound. The antenna structure 2 including the non-coil winding portion 22 not shown is shown.

  In another embodiment of the present invention, the antenna characteristics of the antenna structure 2 as shown in FIG. 6 are designed to have the above-described characteristics.

  Here, the Q value used in the present invention will be outlined with reference to FIG.

  FIG. 7 is a graph showing the relationship between the frequency and the output of the antenna. In FIG. 7, the frequency with the highest antenna output is the resonance frequency f0.

  In FIG. 7, the level indicated by A is about 3 dB (1 / √2) lower than the highest point of the antenna output, and if the frequencies giving the output levels are f1 and f2, the Q value is It is calculated as follows.

Q value = resonance frequency f0 ÷ (f2−f1)
As another interpretation of the Q value, as described above, the Q value indicates the degree of energy loss of the antenna in a resonance state, and the smaller the energy loss, the higher the Q value.

  As a result, the antenna output is approximately equal to the Q value of the antenna input.

  That is, when the output characteristic value of the antenna structure 2 is defined by the Q value, the Q value indicates the ratio of the output to the input to the antenna structure 2. This indicates that the antenna has an output characteristic of approximately 100, and the higher the Q value, the better the antenna structure.

  That is, the higher the Q value is, the higher the performance of the antenna structure is determined to be. In other words, the Q value is an index indicating the magnitude of the energy loss.

  In the present invention, increasing the Q value makes it possible to remove unnecessary noise from the input external radio wave, thereby improving the sensitivity to a predetermined frequency. Since it becomes possible, a filter function can be exhibited, and from this point, a high Q value is desired.

  Therefore, in the antenna structure 2 shown in FIG. 6 described above, when the antenna structure 2 is disposed in contact with or close to the exterior part made of a metal material, sufficient antenna output is obtained. As a result of studying how to prevent the decrease of the Q value and suppress the decrease in the antenna output to a practically acceptable level in order to ensure Basically, the antenna structure 2 receives a radio wave. The antenna structure 2 can receive the magnetic flux 4 due to the external radio wave. However, at the time of resonance, the magnetic flux 7 generated by the resonance hardly leaks to the outside. The magnetic path 6 has a coil winding portion 21 around which the conductor 11 is wound to form a coil, and a non-coil winding portion 22 around which the conductor 11 is not wound. Ante By the structure, in practical no problem small, thin, and low manufacturing cost, it is an easily manufactured antenna structure suitable for electronic devices Telecommunications.

  In other words, the structure of the antenna structure 2 used in the present invention will be described in more detail. In FIG. An antenna having a structure that receives a magnetic flux 4 by radio waves, but a magnetic flux 7 generated by resonance flows through a closed-loop magnetic path 6, and as a result, the magnetic flux 7 does not easily leak out of the antenna structure 2. This is a structure 2.

  More specifically, in the antenna structure 2 of the present invention, at least a part of the coil winding portion 21 and at least a part of the non-coil winding portion 22 in the magnetic path 6 are made of different materials. It is desirable that it is done.

  The coil winding portion 21 according to the present invention constitutes a part of the magnetic path 6 described above, and an appropriate conductor 11 is wound around an appropriate core portion 9 a predetermined number of times. The non-coil-wound portion 22 of the antenna structure 2 used in the present invention constitutes a part of the magnetic path 6 described above. The core portion 9 ′ is defined by a portion where the coil of the conductor 11 is not wound around the core portion 9 ′.

  That is, when the antenna receives an external radio wave, the magnetic flux 4 generated by the external radio wave mainly causes the coil winding portion 21 of the antenna structure 2 used in the present invention. The non-coil winding part 22 has a function of flowing the magnetic flux 7 generated while the coil winding part 21 is resonating. It has a function of flowing to the coil winding portion 22.

  Therefore, for example, even if a coil made of an appropriate conductor is wound around a portion corresponding to the non-coil winding portion 22, as long as the above-described function is exerted, the portion is not coiled. Department.

  For example, if a coil is wound around both the coil winding portion 21 and the non-coil winding portion 22 and if both coils resonate, the resonance phases of both coils are shifted, so the output is Not only does it decrease, but it is difficult to adjust the resonance frequency of both coils, and the volume and the number of parts increase.

  On the other hand, in the above example, when the antenna of the coil winding portion 21 on the output side is non-resonant, the coil resistance of the coil winding portion is added, the copper loss in the resonance state increases, and the output decreases. An increase in other volumes and the number of parts also poses a problem.

  The coil winding portion 22 according to the present invention is not limited to a single coil, and may include a plurality of coils.

  Further, in the present invention, regarding the antenna structure 2, in order not to hinder reception of an external radio wave, for example, the effective magnetic permeability of the coil winding portion 21 may be smaller than the non-coil winding portion 22. And the effective magnetic permeability is smaller than the magnetic path in air through which the magnetic flux generated when the coil winding portion 21 resonates when the non-coil winding portion 22 does not exist is present. Needs to be configured to be large.

  Therefore, it is desirable that at least a part of the material forming the coil winding portion 21 and the non-coil winding portion 22 be different from each other.

  On the other hand, in the present invention, the magnetic flux of the external radio wave entering the coil winding portion 21 and the non-coil winding portion 22 mainly flows through the coil winding portion 21 having a large effective magnetic permeability. An electromotive force is generated in the coil unit 8, and the electromotive force causes resonance. The magnetic flux generated by the resonance is higher than the effective magnetic permeability in the air rather than flowing from the coil winding unit 21 into the air. Since the flow mainly flows to the non-coil winding portion 22 having a large effective magnetic permeability, the magnetic flux leaking to the outside of the antenna structure is reduced as a result.

  FIG. 6 shows that the gap 10 is provided in a part of the magnetic path 6 corresponding to the non-coil winding portion 22 of the antenna structure 2 of the present invention to form a magnetic gap. The effective magnetic permeability of the coil winding portion 22 is reduced.

  As described above, the antenna structure 2 used in the present invention has a reduced Q value even when the metal material 3 is in contact with or near the metal material 3. The rate is greatly suppressed, and, as described above, the fact that the antenna characteristics of the antenna structure 2 itself have been significantly improved is also combined, so that in practice, regardless of the presence or absence of the metal material, Thus, the antenna structure 2 that can exhibit good receiving performance can be obtained easily and at low cost.

  As is clear from the above description, in the present invention, the magnetic permeability of one part of the magnetic path 6 of the antenna structure 2 constituting the closed loop is the same as that of the other part. It is a preferable specific example that a different portion is included.

  Further, in the antenna structure 2 used in the present invention, a part of the magnetic path 6 of the antenna structure 2 constituting the closed loop has a magnetic resistance which is different from that of another part. It is also a desirable example that a portion different from the magnetoresistance is included.

  On the other hand, the antenna structure 2 used in the present invention is configured such that the effective magnetic permeability of the non-coil winding portion 21 is smaller than the effective magnetic permeability of the coil winding portion 22. It is also desirable to have.

  Further, in the present invention, it is possible to use the antenna structure 2 having a configuration as shown in FIGS. 8A to 8E, and the gap 10 in the non-coil winding portion 22. Is also preferably provided.

  In the present invention, in the antenna structure 2 used, as shown in FIG. 8 (A) or (B), the coil winding portion 21 and the non-coil winding It is desirable that the gap 10 is formed in at least one of the joining portions 15 with the portion 22.

  In the present invention, the gap is desirably provided in a portion of the magnetic path 6 other than the vicinity of the coil winding portion 21 as shown in FIG. 8A or 8B.

  On the other hand, as shown in FIG. 8D, it is not preferable that at least a part of the gap 10 is present on the surface of the antenna structure 2 where the external radio wave reaches, and therefore, FIG. As shown in (C), the gap 10 is desirably formed on the side surface of the coil winding portion 21 opposite to the surface on which the external radio wave reaches.

  Specifically, as shown in FIG. 8 (B), the antenna core 9 of the coil winding portion 21 extends from the center axis 28 of the portion extending outward from the coil to the radius of the antenna core. The gap 10 has a configuration in which the end face of the non-coil winding portion 22 is joined to a part of the surface opposite to the central axis at a position separated by the length and opposite to the surface on which the external radio wave reaches. Is desirably formed.

  On the other hand, in the present invention, it is desirable that the non-coil wrapped portion 22 is formed of a magnetic material having a lower magnetic permeability than the magnetic material constituting the coil wrapped portion 21. As shown in FIG. 8 (E), the non-coil wrapped portion 22 or at least a part of the surface of the coil wrapped portion 21 is formed of a magnetically altered layer, a non-magnetic layer, or a layer having low magnetic permeability. It is also preferable to form the film layer 80.

  In this case, the gap 10 may be composed of the film layer alone without the intervening air layer.

  Furthermore, in the present invention, the coil winding part 21 and the non-coil winding part 22 may be configured so that the cross-sectional areas thereof are different from each other. The coiled portion 22 and the non-coiled winding portion 22 are formed separately from each other. After the conductor 11 is wound around the coiled portion 21 and the coil 8 is formed, the coiled portion 21 and the non-coiled portion are formed. 22 can be adopted.

  As described above, even when the antenna structure 2 according to the present invention is in contact with the metal material or in the case where the metal material is present in the vicinity thereof, the reduction rate of the Q value is greatly suppressed. Practically, the antenna structure 2 capable of exhibiting good reception performance can be obtained easily and at low cost regardless of the presence or absence of the metal material.

  In the present invention, the frequency of the target radio wave that can be received by the antenna structure 2 is a radio wave including a long wave of 2000 kHz or less, and preferably a long wave of several tens of kHz to several hundreds of kHz.

  On the other hand, the metal exterior 3 used in the present invention is, specifically, stainless steel (SUS), gold, silver, platinum, titanium (Ti), nickel, copper, chromium, aluminum, or brass (BS). ) Or a metal exterior material having conductivity such as an alloy thereof is used.

  In addition, a preferable metal exterior material in the present invention is BS, SUS or Ti.

  Further, in the present invention, specific examples of the metal exterior 3 disposed in the vicinity of the antenna structure 2 include, for example, a watch exterior including a back cover and a side, a dial, a motor, a movement, It includes batteries, solar cells (SUS substrate solar cells), arm bands, heat sinks, and the like.

  Next, an example of a specific configuration for realizing the above-described antenna structure 2 according to the present invention will be described below.

  That is, the antenna structure 2 used in the present invention preferably has a configuration as shown in FIG. 6, for example. Specifically, the antenna structure 2 is provided with a winding 11 which is a coil. The magnetic core <core portion> 9 constituting the path 6 is extended from both ends and bent, and the ends 13 and 13 ′ are brought close to each other to form a loop-shaped magnetic path.

  In this specific example, it is desirable that a small gap, that is, a gap 10 is provided in the facing portion 14 between the ends of the magnetic core 9.

  As described above, the gap 10 may be one in which air is interposed, or may be one in which an appropriate film layer is interposed. Since the gap may be interposed, the gap 10 has a magnetic resistance higher than the magnetic resistance in the magnetic path, and therefore, a part of the closed loop of the magnetic path (core) 6 has a magnetic resistance. Will be formed.

  In the present invention, the gap portion may be configured to have a magnetic resistance or magnetic permeability different from, for example, the magnetic resistance or magnetic permeability of the other portion, or the gap may be formed in the gap. May be arranged or filled with a material different from the material constituting the magnetic core.

Since the antenna structure 2 used in the present invention has a substantially loop-shaped antenna structure in which the above-described gap exists, the magnetic flux coming in from the outside can be applied to both ends of the antenna. However, the magnetic flux does not flow in the direction where the gap 10 (the magnetic resistance is medium), but flows to the winding portion 11 having a small magnetic resistance. (If there is no gap, flow in the direction of the gap.)
As described above, the winding portion 11 affected by magnetism converts a change in magnetic flux into a voltage, causes a resonance phenomenon by the L value of the antenna and the capacitance of the tuning capacitor, and generates a magnetic flux due to resonance. However, at this time, the magnetic flux generated by the resonance phenomenon of the antenna does not leak into the air but flows through a gap portion having a small magnetic resistance.

  This makes it possible to reduce the loss that occurs when the antenna is placed inside the metal exterior.

  In other words, since the magnetic path 6 of the antenna structure 2 forms a closed magnetic path, it is generated by the resonance output from the antenna structure 2 when the antenna structure 2 resonates. Since the flow of the magnetic flux 7 flows mainly along the closed loop-shaped magnetic path 6 as shown in FIG. 6, the magnetic flux 7 flows from the antenna structure 2 to, for example, the exterior part 3 made of the metal material. Leakage of the magnetic flux is avoided, so that the magnetic flux leaking to the metal exterior part 3 does not generate an eddy current and lower the energy of the magnetic flux.

  As shown in FIG. 6, the magnetic path (core) 6 in the antenna structure 2 has the antenna core (main magnetic path) 9 of the coil winding part 21 and the antenna core (not shown) of the non-coil winding part 22. In the case where an antenna is manufactured, the antenna core portion (main magnetic path) that forms the coil winding portion 21 through the gap of the gap 10 when an antenna is manufactured, 9 or wound around the antenna core portion 9 constituting the coil winding portion 21 using a closed space formed between the coil winding portion 21 and the non-coil winding portion 22. Must be turned on, and productivity will be reduced.

  Therefore, when the antenna core part (main magnetic path) 9 of the coil winding part 21 and the antenna core part (sub magnetic path) 9 ′ of the non-coil winding part 22 are separately provided and manufactured, At the stage where the coil winding is performed on the antenna core 9 of the winding unit 21, the antenna core 9 ′ of the non-coil winding unit 22 is not attached, and after the winding operation is completed, the antenna of the non-coil winding unit 22 is completed. By attaching the core portion 9 ', it is possible to dramatically improve the winding production efficiency.

  That is, as shown in FIG. 9, as another specific example of the antenna structure 2 used in the present invention, the antenna core portion (main magnetic path) 9 of the coil winding portion 21 and the non-coil winding The antenna core portion (sub magnetic path) 9 'of the attachment portion 22 is formed separately, and the two are joined after the winding operation is completed.

  At this time, this is one of the preferable specific examples in which the magnetic resistance of the non-coil winding portion 22 according to the present invention is configured to be higher than the magnetic resistance of the coil winding portion 21.

  On the other hand, in the present invention, the gap 10 may be formed in the non-coil winding portion 22 or, as shown in FIG. The gap 10 may be provided between the coil winding portion 21, that is, at least one of the two joining portions 15.

  Further, in another specific example of the present invention, it is also a preferable specific example that the cross-sectional areas of the coil winding portion 21 and the non-coil winding portion 22 are different from each other.

  That is, as shown in FIG. 9, the cross-sectional area of the coil winding portion 21 is configured to be smaller than the cross-sectional area of the corresponding non-coil winding portion 22.

  This is because, as shown in the figure, it is necessary to wind the winding wire 11 around the coil winding portion 21. Therefore, when the cross-sectional area of the coil winding portion 21 is large, the winding wire is wound. The subsequent cross-sectional area also increases, for example, causing the problem that the thickness of the watch is increased, and a thin watch cannot be manufactured.

  As shown in FIG. 9, in the antenna structure 2 according to the present invention, the coil winding portion 21 and the non-coil winding portion 22 form mutually independent components. After the coil 11 is wound around the coil winding portion 21, the coil winding portion 21 and the non-coil winding portion 22 are joined and integrated.

  Further, as described above, the gap 10 is formed in at least one joint 15 between the coil winding portion 21 and the non-coil winding portion 22 of the antenna structure 2 according to the present invention. The gap 10 formed between the coil winding portion 21 and the non-coil winding portion 22 is a joint surface 15 between the coil winding portion 21 and the non-coil winding portion 22 and end faces thereof. It is possible to fix a predetermined gap by inserting an appropriate spacer 17 into the space.

  The spacer 17 may use a foreign substance such as a bead, or may use a projection 17 formed on a bobbin 16 that supports the antenna structure 2. good.

  That is, in this specific example, the gap length of the gap 10 formed on the joint surface 15 between the antenna core portion 9 of the coil winding portion 22 and the antenna core portion 9 ′ of the non-coil winding portion is previously set on the bobbin 16. Positioning is performed with the formed projections 17 or spacers 17 separately provided to improve the gap accuracy of the gap.

  Therefore, a bobbin, a spacer 17, an appropriate film layer 80, or the like is interposed in the gap between the coil-wound portion antenna core portion 9 and the non-coil-wound portion 22 of the antenna core portion 9 ', so that An error in the distance accuracy between the 10 leads to a dimensional accuracy error of a foreign substance such as a protrusion of the bobbin or a spacer, and the gain of the antenna can be stabilized.

  Further, with respect to the antenna structure 2 according to the present invention, the joining surface 15 between the end faces 19 formed between the coil winding portion 21 and the non-coil winding portion 22 is formed in a tapered shape. Is desirable.

  That is, the joining surface 15 between the end faces 19 forming the gap 10 formed between the coil winding portion 21 and the non-coil winding portion 22 is formed obliquely with respect to the winding portion 11. By doing so, the area of the gap 10 is increased.

  By adopting such a configuration, the gap distance of the gap 10 can be adjusted by pushing or pulling out the antenna core portion 9 ′ of the non-coil wrapped portion with respect to the antenna core portion 9 of the coil wrapped portion. It can be easily adjusted by moving it.

  Further, in such a configuration, as described above, the variation in the gain of the antenna depends on the magnetic field between the antenna core 9 of the coil winding portion 21 and the antenna core 9 ′ of the non-coil winding portion 22. This is the effect of the increase and decrease of the resistance value. If the contact surface of the gap becomes large, the rate of change of the gain of the antenna with respect to the distance between the gaps is reduced. Therefore, it is advantageous to increase the contact area of the gap.

  In other words, by configuring as in this specific example, it is possible to increase the contact area of the gap portion by よ り 2 times as compared with making the contact area parallel to the winding portion 11, so that it is possible to reduce the variation in the gain of the antenna. It becomes.

  In FIG. 9, reference numeral 18 denotes a winding frame when the winding 11 is wound around the antenna core portion 9 of the coil winding portion 21, and reference numeral 20 denotes an electrically conductive core of the coil winding portion 21. In this case, an insulating material inserted between the antenna core 9 and the winding 11 is shown.

  On the other hand, with respect to the gap 10 in the present invention, each magnetic path in the end surface of the coil winding portion 21 and the non-coil winding portion 22 or in a portion other than the end surfaces of the non-coil winding portion 22 is used. May be formed so that the surfaces thereof face each other.

  That is, as shown in FIG. 10A, when the gap 10 is formed in a part of the antenna core 9 ′ of the non-coil winding part 21, the non-coil winding part 22 does not. At least a part of the end portions 13 of the antenna core portion 9 ′ are not overlapped with each other, but at least a part of the end portions 13 are overlapped with each other. The surfaces 26 and 26 ′ of the magnetic path may be formed so as to face each other, or, as shown in FIG. 10B, the end surface 19 of the antenna core 9 of the coil winding part 21. When the gap 10 is formed between the end face 19 ′ of the antenna core portion 9 ′ of the non-coil winding portion 22 and at least a part of the gap 19 without facing the end portions 19. Other than the end face 19 ′ of the non-coil winding part 22 Portion 27 'and a portion 27 other than the end face 19 of the coil winding portion 21 may be one that is formed to face.

  As shown in FIG. 10 (C), the coil 100 formed in an air-core coil or bobbin was formed on the air-core coil or bobbin with two L-shaped antenna cores 200 and 201 facing each other. The coil 100 may have a structure in which the coil 100 is inserted separately from both ends into the center thereof so that both parts are arranged to face each other.

  On the other hand, in the structure of the antenna structure 2 according to the present invention, both side portions 23 of a portion forming the antenna core portion 9 of the coil winding portion are tapered or have an appropriate curve as shown in FIG. Alternatively, a curved surface formed by a polygonal line may be formed.

  In this case, the both side portions 23 are adapted as much as possible to the outer peripheral shape of the timepiece, and the coil winding portion 21 of the antenna structure 2 can be arranged on the outer peripheral portion of the timepiece as much as possible. I can do it.

  Further, in the present invention, the cross-sectional area or thickness of the antenna core 9 'of the non-coil-wound portion in the antenna structure is larger than the cross-sectional area or thickness of the antenna core 9 of the coil-wound portion. It is also a preferable specific example that the thickness is increased.

  As described above, in order to reduce the magnetic resistance between the antenna core portion 9 of the coil-wound portion and the antenna core portion 9 'of the non-coil-wound portion, the antenna core portion 9 of the coil-wound portion must be It is desirable that the thickness or the cross-sectional area of the antenna core portion 9 ′ of the coil winding portion is thicker or larger, but since the winding portion 11 is provided in the antenna core portion 9 of the coil winding portion, the coil winding portion is provided. If the cross-sectional area of the antenna core portion 9 of the portion or the thickness thereof is large or thick, the thickness of the antenna structure 2 increases accordingly. However, there is no winding portion 11 in the antenna core portion 9 'of the non-coil winding portion. Therefore, the antenna core portion 9' of the non-coil winding portion is thicker than the antenna core portion 9 of the coil winding portion by the thickness of the winding portion or the cross-sectional area thereof is reduced. It is possible to make it larger.

  With this configuration, the magnetic resistance between the antenna core portion 9 of the coil-wound portion and the antenna core portion 9 'of the non-coil-wound portion is reduced, so that more magnetic flux generated by resonance is generated. It can be guided to the antenna core portion 9 'of the coil winding portion, and it becomes possible to suppress variations in antenna gain.

  And preferably, the antenna core portion 9 'of the non-coil winding portion is disposed inside the antenna core portion 9 of the coil winding portion with respect to the traveling direction of the radio wave, and The antenna core portion 9 covers the antenna core portion 9 'of the non-coil-wound portion, and is configured such that radio waves do not directly reach the antenna core portion 9' of the non-coil-wound portion. .

  Therefore, when the antenna core portion 9 of the coil winding portion constituting the antenna structure 2 is mounted on a wristwatch or the like, the watch is placed at a position where the watch is likely to directly receive radio waves on average, and It is desirable to dispose the non-coil-wound portion antenna core portion 9 ′ on the surface opposite to the surface of the coil-wound portion antenna core portion 9 to which radio waves are applied.

  That is, the magnetic flux entering the antenna core portion 9 of the coil winding portion does not flow in the direction of the antenna core portion 9 ′ of the non-coil winding portion where the gap 10 is present, and the magnetic flux enters the winding portion 11 having a small magnetic resistance. On the contrary, the magnetic flux entering the antenna core portion 9 'of the non-coil winding portion does not flow to the non-coil winding portion antenna core portion 9' where the gap 10 exists.

  Therefore, it is desirable that the antenna has a structure in which magnetic flux enters the antenna core portion 9 of the coil winding portion.

  With this configuration, most of the magnetic flux that has entered the antenna from the outside enters the antenna core portion 9 of the coil winding portion, so that the gain is improved.

  The specific configuration of the antenna structure 2 in the above-described antenna structure 2 according to the present invention is as shown in FIG. It is designed so as to cover the antenna core portion 9 'of the coil winding portion.

  As another aspect of the present invention, as shown in FIG. 11, a reference signal generating means 31 for outputting a reference signal, a timing means 32 for outputting timing information based on the reference signal, and A receiving means 34 for receiving a standard radio wave having reference time information, and an output time correcting means for correcting output time information of the clocking means based on a signal received from the receiving means 34. 35, the receiving means 34 is the radio-controlled timepiece 1 including any one of the antenna structures 2 having the above-described configuration.

  The radio-controlled timepiece 1 according to the present invention includes a radio-controlled timepiece or a remote control type wristwatch that receives a standard radio wave with a time code and automatically adjusts the time of a wristwatch in use to the time of the standard time. It is what is done.

  FIG. 12 shows a detailed specific example of the radio-controlled timepiece 1 according to the present invention. In the radio-controlled timepiece 1, the antenna structure 2 having the configuration shown in FIG. Of course, the coil-wound portion antenna core 9 of the antenna structure 2 is positioned near the outer edge 51, and the non-coil-wound antenna core 9 'is moved to the coil-wound antenna. The configuration in which the core portion 9 is arranged on the side opposite to the outer edge portion 51 of the timepiece is shown.

  In FIG. 12, 52 is a receiving IC, 53 is a crystal oscillator for a filter, 54 is a crystal oscillator of 32 KHz, 55 is a train of gear trains, 56 is a crown, 57 is a back circumference mechanism, 58 Is a first converter (motor), 59 is a battery, and 40 is a microcomputer that constitutes an arithmetic processing unit including a clock unit or a time correction unit.

  FIG. 13 shows another specific example of the radio-controlled timepiece 1 according to the present invention in which the configuration of FIG. 12 is partially changed. The difference from FIG. 12 is that FIG. A second converter (motor) 41 is separately provided in addition to the first converter (motor) 58.

  Next, the radio-controlled timepiece 1 according to the present invention has a metal exterior part 42, and the antenna structure 2 is also arranged in the exterior part 42 depending on the case. At least a part of the antenna structure 2 may be in contact with the exterior part 42.

  Of course, the arrangement configuration example of the radio-controlled timepiece 1 in FIGS. 12 and 13 is merely an example, and as described above, the antenna structure 2 of the antenna structure 2 according to the present invention is made of a metal material. Since the influence of the presence of the conductive object is small, the relationship with the arrangement of other components is flexible, and thus many variations are possible.

  Further, in another specific example of the present invention, as shown in FIG. 14, the antenna structure 2 is provided on the dial 46 of the radio-controlled timepiece 1 with the windshield 43 provided thereon. It is also a desirable mode to provide it on the surface on the opposite side to the above.

  In FIG. 14, reference numeral 44 denotes a conductive exterior part made of a metal material, and reference numeral 45 denotes an hour / minute hand constituting display means.

  According to another aspect of the present invention, there is provided a radio-controlled timepiece in which at least one of a side portion and a back cover is made of metal, and an antenna built in the radio-controlled timepiece includes: A radio-controlled timepiece comprising an antenna structure having at least one antenna characteristic value described above.

  Further, in another aspect of the present invention, there are provided a reference signal generating means for outputting a reference signal, a timing means for outputting time information based on the reference signal, and a display for displaying time based on the time information. Means, a receiving means for receiving a standard radio wave having reference time information, and a radio-controlled timepiece for correcting output time information of the timekeeping means based on a signal received from the receiving means, wherein the radio-controlled timepiece is at least A radio-controlled timepiece including one of a side portion and a back cover portion made of metal, and including an antenna structure having at least one antenna characteristic value described above.

  According to still another aspect of the present invention, the coil-wound portion of the antenna structure is disposed on an outer peripheral portion of the radio-controlled timepiece, and the non-coil-wound portion is disposed on the radio-controlled timepiece. The receiving means disposed inside the coil winding portion with respect to the outer peripheral edge of the antenna is a radio-controlled timepiece further including an antenna structure having at least one antenna characteristic value described above.

  On the other hand, as still another aspect of the present invention, the antenna structure has at least one of the above-described configuration and antenna characteristics, and a windshield is attached to the dial of the radio-controlled timepiece. This is a radio-controlled timepiece provided on a surface opposite to the provided surface.

  According to still another aspect of the present invention, there is provided an antenna structure provided in the radio-controlled timepiece, wherein the antenna structure has at least one of the above-described configuration and antenna characteristics. At least a part of the portion of the body where the non-coil wrapped portion faces the side portion of the radio-controlled timepiece is a radio-controlled timepiece covered by the coil wrapped portion.

  FIG. 15 is a diagram showing an example of a method of adjusting the resonance frequency in the antenna structure used in the present invention, and FIG. 15A shows a conventional method of adjusting the resonance frequency. When a plurality of capacitors 151 to 153 each having a capacitance of 80 pF are attached in parallel to both ends of the winding 150 and measurement is performed, and the resonance frequency of the antenna structure 2 is changed, It is necessary to change the capacity of the capacitor to an appropriate value or to change the number of connected capacitors, which complicates the measurement operation.

  On the other hand, in the present invention, as shown in FIG. 15B, a plurality of capacitors 151 to 15n connected to both ends of the winding 150 and the same number of switch circuits SW1 to SWn are respectively connected in series. A tuning IC circuit 160 configured to connect a plurality of connected adjusting means in parallel is mounted, and a capacitor obtained by doubling the capacity of the plurality of capacitors 151 to 15n, for example, sequentially from 1.25 pF is used. The control terminals of the switch circuits SW1 to SWn are connected to an appropriate control counter means 161 and one or a plurality of the control circuits are desired in response to a signal input to an input terminal of the control counter means 161. A desired L value is easily set by controlling and driving the control terminals of the switch circuits SW1 to SWn so as to appropriately select the capacitors. Thing is possible.

  Since the present invention employs the above-described configuration, it is possible to solve the above-described problems of the prior art and to simplify the structure, exterior material, or design of the conventional radio-controlled timepiece without any significant change. By adopting an antenna structure having a configuration, the reception efficiency is good, the size and thickness of the watch itself are not different from the conventional one, the degree of freedom in design is increased, and the manufacturing cost can be kept low. It is possible to obtain an antenna structure and a radio-controlled timepiece using the antenna structure.

  Furthermore, even when the antenna is housed in the metal exterior, a radio-controlled timepiece with a high commercial value without lowering the gain can be obtained.

FIG. 1 is a diagram showing a configuration of a specific example of the antenna structure according to the present invention. FIG. 2 is a graph showing a relationship between an L value and a gain in the antenna structure. FIG. 3 is a graph showing the relationship between the number of windings (T) and the gain in the antenna structure. FIG. 4 is a graph showing the relationship between the winding resistance (Ω) and the gain in the antenna structure. FIG. 5 is a graph showing the relationship between the winding resistance (Ω) and the gain in the antenna structure. FIG. 6 is a plan view showing a specific example of the configuration of the antenna structure used in the present invention. FIG. 7 is a diagram illustrating a specific example of a method for measuring an antenna gain and a Q value according to the present invention. FIG. 8 is a diagram illustrating an example of another configuration of the antenna structure used in the present invention. FIG. 9 is a plan view showing another specific example of the configuration of the antenna structure used in the present invention. FIG. 10 is a diagram illustrating a configuration example of a gap portion in the antenna structure used in the present invention. FIG. 11 is a block diagram showing an example of the configuration of the radio-controlled timepiece according to the present invention. FIG. 12 is a diagram showing a specific example of an arrangement configuration of each component in the radio-controlled timepiece according to the present invention. FIG. 13 is a diagram showing another specific example of the arrangement configuration of each component in the radio-controlled timepiece according to the present invention. FIG. 14 is a diagram showing another specific example of the arrangement configuration of each component in the radio-controlled timepiece according to the present invention. FIG. 15 is a block diagram showing a circuit configuration used to change the L value of the antenna structure according to the present invention. FIG. 16 is a diagram illustrating a specific example of a method for measuring an antenna gain and a Q value according to the present invention. FIG. 17 is a diagram illustrating a specific example of a method for measuring an antenna gain and a Q value according to the present invention. FIG. 18 is a diagram showing the configuration of another specific example of the antenna structure according to the present invention. FIG. 19 is a characteristic diagram showing the relationship between the winding resistance and the antenna Q value in the second embodiment of the present invention. FIG. 20 is a characteristic diagram of the frequency-L value in the embodiment of the second mounting portion of the present invention.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Radio-controlled timepiece 2 Antenna structure 3 Exterior part, metal exterior 4 Flux by external radio waves 6 Magnetic path 7 Magnetic field lines (magnetic flux)
Reference Signs List 8 Coil portion 9, 9 'Antenna core portion 10 Gap 11 Winding portion 13 Magnetic path end portion 14 End-to-end facing portion 15 Joining portion 16 Bobbin 17 Spacer, projection, bead 18 Fixing pin 19 End surface 20 Insulating material 21 Coil Winding part (main magnetic path)
22 Non-coil winding part (sub magnetic path)
23 Both sides 26 Surface part other than the end face of the antenna core part 27 Surface part other than the end face of the antenna core part 28 Center axis 31 of the antenna core part Reference signal generating means 32 Clocking means 33 Display means 34 Receiving means 35 Output time correcting means 40 Arithmetic processing unit, microcomputer 41, second converter (motor)
42, 44 Metal exterior part 43 Glass windshield 46 Dial 45 Hour and minute hands 51 Outer edge part of watch 52 Receiving IC
53 Filter crystal unit 54 32 KHz crystal unit 55 Wheel train 56 Crown 57 Back rotation mechanism 58 First converter (motor)
59 batteries

Claims (34)

  An antenna structure capable of receiving a radio wave disposed in a structure in which at least one of a side portion and a back cover portion is made of metal, wherein the L value of the antenna is 1600 mH or less. Structure.   The said L value is 800 mH or less, The antenna structure of Claim 1 characterized by the above-mentioned.   The said L value is 220 mH or less, The antenna structure of Claim 1 characterized by the above-mentioned.   An antenna structure capable of receiving radio waves disposed in a watch having at least one of a side portion and a back cover portion made of metal, wherein a winding resistance of the antenna is 1 KΩ or less. Antenna structure.   The antenna structure according to claim 4, wherein the winding resistance is 400Ω or less.   The antenna structure according to claim 4, wherein the winding resistance is 100Ω or less.   An antenna structure capable of receiving radio waves disposed in a timepiece in which at least one of a side portion and a back cover portion is made of metal, wherein the number of windings of the antenna is 400 or more. Antenna structure.   The antenna structure according to claim 7, wherein the number of windings is 1,000 or more.   The antenna structure according to any one of claims 4 to 6, wherein the winding has a wire diameter of 0.1 mmφ or less.   An antenna structure that receives a radio wave, the antenna structure can receive a magnetic flux due to an external radio wave, but has a magnetic path structure in which a magnetic flux generated by resonance hardly leaks outside. 10. A coil winding portion in which at least one conductor is wound to form a coil, and a non-coil winding portion in which the conductor is not wound. 4. The antenna structure according to claim 1.   The antenna structure according to claim 10, wherein the coil-wound portion and at least a part of the non-coil-wound portion in the magnetic path are made of different materials.   The antenna structure according to claim 10, wherein the magnetic path in the antenna structure through which a magnetic flux generated by resonance passes forms a closed loop.   13. A part of the magnetic path of the antenna structure forming the closed loop includes a part whose magnetic permeability is different from the magnetic permeability of another part. 4. The antenna structure according to claim 1.   14. A part of the magnetic path of the antenna structure forming the closed loop includes a part whose magnetic resistance is different from the magnetic resistance of another part. The antenna structure according to any one of the above.   The antenna structure according to any one of claims 10 to 14, wherein the effective magnetic permeability of the non-coil-wound portion is smaller than the effective magnetic permeability of the coil-wound portion.   The antenna structure according to any one of claims 10 to 15, wherein a gap is provided in the non-coil winding portion.   17. The antenna structure according to claim 16, wherein a gap is formed at at least one of the joining portions between the coil winding portion and the non-coil winding portion.   The antenna according to any one of claims 10 to 17, wherein the non-coil-wound portion is formed of a magnetic material having a lower magnetic permeability than a magnetic material forming the coil-wound portion. Structure.   11. A film layer comprising a magnetically altered layer, a non-magnetic layer, or a layer having low magnetic permeability is formed on the non-coil-wound portion or at least a part of the surface of the coil-wound portion. 19. The antenna structure according to any one of claims 18 to 18.   20. The antenna structure according to claim 10, wherein a sectional area of the coil-wound portion and a cross-sectional area of the non-coil-wound portion are different from each other.   The coil-wound portion and the non-coil-wound portion form mutually independent components, and after the coil is formed by winding a conductor around the coil-wound portion, the coil-wound portion and the non-coil 21. The antenna structure according to claim 10, wherein the antenna structure is integrated with a coil winding portion.   The gap provided in the non-coil wrapped portion or formed between the coil wrapped portion and the non-coil wrapped portion is formed between the coil wrapped portion, the non-coil wrapped portion, and the end face. The antenna structure according to any one of claims 16 to 21, wherein the antenna structure is formed by inserting an appropriate spacer into the joint surface of (1).   A joining surface of the gap provided in the non-coil winding portion or a joining surface of end surfaces formed between the coil winding portion and the non-coil winding portion is formed in a tapered shape. The antenna structure according to any one of claims 16 to 22, wherein:   The gap is formed such that the surfaces of the magnetic paths at the end surfaces of the coil winding portion and the non-coil winding portion or at portions other than the end surfaces of the non-coil winding portion face each other. The antenna structure according to any one of claims 16 to 23, wherein:   The antenna structure according to any one of claims 16 to 24, wherein the gap is provided in a portion of the magnetic path other than near the coil winding portion.   26. The antenna structure according to claim 16, wherein the gap portion is configured to have a magnetic resistance or a magnetic permeability different from the magnetic resistance or the magnetic permeability of the other portion.   The antenna structure according to any one of claims 16 to 26, wherein a material different from a material forming the magnetic core is arranged in the gap.   28. The antenna structure according to claim 27, wherein the gap is filled with a material different from a material forming the magnetic core.   The antenna structure according to any one of claims 10 to 28, wherein the gap is an air gap.   30. The radio-controlled timepiece having at least one of a side portion and a back cover portion made of metal, wherein the antenna built in the radio-controlled timepiece is the antenna according to any one of claims 1 to 29. A radio-controlled timepiece characterized by being composed of a structure.   A reference signal generator for outputting a reference signal, a timer for outputting clock information based on the reference signal, a display for displaying time based on the clock information, and receiving a standard radio wave having reference time information A receiving means, and a radio-controlled timepiece for correcting output time information of the time-measuring means based on a signal received from the receiving means, wherein at least one of the side part and the back cover part is made of metal. 30. A radio-controlled timepiece, wherein said receiving means includes an antenna structure having a structure according to any one of claims 1 to 29.   30. The coil-wound portion of the antenna structure according to any one of claims 1 to 29 is disposed on an outer peripheral edge of the radio-controlled timepiece, and the non-coil-wound portion is an outer peripheral edge of the radio-controlled timepiece. A radio-controlled timepiece which is arranged inside the coil winding part with respect to the part.   The antenna structure according to any one of claims 1 to 29, wherein the antenna structure is provided on a surface opposite to a surface on which a windshield is provided with respect to the dial of the radio-controlled timepiece. A radio-controlled watch that does   An antenna structure provided in the radio-controlled timepiece, wherein the non-coil-wound portion of the antenna structure according to any one of claims 1 to 29 faces the side portion of the radio-controlled timepiece. A radio-controlled timepiece, wherein at least a part of the part is covered by the coil winding part.

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