JP4202878B2 - Antenna structure and radio wave correction watch - Google Patents

Description

  The present invention relates to an antenna structure and a radio wave correction watch using the antenna structure, and more particularly, in a resonant antenna, even when the antenna structure is disposed in the vicinity of a metal object, the radio wave of the antenna structure is related. The present invention relates to an antenna structure configured so as not to deteriorate the reception performance of the radio wave and a radio wave correction timepiece using the antenna structure.

  In recent years, many watches using radio waves have been commercialized.

  That is, a radio function is added to the inside of the wristwatch, and a radio wristwatch that receives broadcast radio waves to obtain predetermined information, or a standard radio wave with a time code received, A radio-controlled timepiece or a remote control type wristwatch that automatically adjusts the time of the wristwatch to the standard time is known.

  However, in order to use radio waves in a wristwatch, it is necessary to have a component configuration or design that is completely different from the conventional watch component configuration and design, and to prevent the reception performance from being hindered.

  That is, there is a design constraint on the size and design of the wristwatch because of the problem of how to improve the reception performance of the antenna and the placement of the antenna in the wristwatch or part of its exterior. To do.

  In particular, an antenna that has a large influence on radio wave reception performance is considerably larger in size than other parts of a conventional wristwatch, and there are restrictions on the arrangement due to the reception performance. Therefore, various methods such as a built-in type, an exterior type, a telescopic type, and a cord type have been conventionally used.

  As a built-in type, a bar antenna consisting of a magnetic core and a winding is mainly used. However, when built in a wristwatch, the reception performance of the antenna should not be reduced by devising the case material and structure or design. It is necessary to.

  In addition, in a telescopic type that is used in an exterior type, a radio cassette, etc., or a cord type that is also used as an earphone or the like, it is necessary to consider the design of the watch as a whole and its storage and durability.

  Under these circumstances, in order to improve the fashionability in addition to the further miniaturization and portability of the wristwatch, not to prevent the reception performance of the antenna device from being lowered, of course, Sufficient consideration should be given to ease and design.

  On the other hand, in the radio-controlled timepiece, it is antenna characteristics and receiving circuit characteristics that determine reception performance.

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

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

  As a type of receiving antenna, a bar antenna in which a conducting wire is wound around a magnetic core is generally used because the wavelength of radio waves is long.

  In such a receiving antenna, the output of the receiving antenna is roughly proportional to the size of the receiving antenna, so it cannot be made very small in order to obtain practical reception performance. Performance and placement become a problem.

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

  For this reason, in order to use radio waves, a wristwatch requires a part configuration or design that is completely different from the conventional timepiece part configuration and design, and also requires consideration not to impede reception performance.

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

  In the case of conventional radio-controlled timepieces, the system of mounting or mounting the antenna is mainly used.

  When the material of the back cover / side of the wristwatch is metal, the receiving antenna is generally sheathed.

  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 has a large projecting shape, which is not only small, thin, and easy to carry, but also greatly reduces the degree of design freedom.

  In the case of a system with a built-in receiving antenna, ceramics or plastic is used as the material for the watch exterior (back cover / side) in order not to deteriorate the receiving performance, but the watch becomes thicker because the strength of the material is small. Performance and portability are impaired, and design restrictions are increased.

  In addition, the wristwatch has a low appearance.

  For this reason, conventionally, for example, as shown in Japanese Utility Model Laid-Open No. 2-126408, a metal antenna is arranged in a leather band of a watch.

  In addition, as disclosed in Japanese Utility Model Publication No. 5-81787, the present applicant arranges an antenna with a coil around a core between a dial and a windshield, and separates it from a metal case main body that blocks radio waves. At the same time, a wristwatch having a unique design, or International Publication WO95 / 27928 discloses a wristwatch having a structure in which an antenna is attached to the side of a wristwatch case.

  Furthermore, as disclosed in European Patent Publication No. 0382130, there is a case where an antenna is arranged in a ring shape on the upper surface of the case.

  However, in the conventional configuration in which the antenna is arranged in the band, since the antenna is built in the band, conduction with the electronic device main body has to be taken, and sufficient flexibility can be provided at the junction between the two. Absent.

  Furthermore, a metal band that interferes with radio waves cannot be used, and a watch band such as a rubber band must be used, which is limited in terms of material and design.

  In addition, the watch with the antenna arranged on the top or side of the watch has an increase in the thickness or size of the watch as a result of the antenna being separated from the metal part of the watch body, and is subject to design constraints. There is a problem.

  Further, in the case of the above-mentioned European Patent Publication No. 0382130, there is a problem that, in practice, the antenna must be separated from the watch because metal cannot be received if a metal exists in the ring. there were.

  Further, Japanese Patent Application Laid-Open No. 11-64547 discloses a wristwatch in which a coil is disposed in a recessed portion provided on a peripheral portion of a circuit board and at the same time, a core is disposed in a curved shape along the circumferential direction of the circuit board. However, there are problems that the manufacturing process becomes complicated and the assembly operation in the manufacturing process becomes complicated.

  On the other hand, in Japanese Patent Application Laid-Open No. 2001-33571 or Japanese Patent Application Laid-Open No. 2001-305244, the windshield and the back cover of the wristwatch are made of a non-metallic material such as glass or ceramic, A wristwatch is shown that is constructed using a conventional metal material so that sufficient radio waves reach the antenna.

  That is, in the above-described conventional example, the output of the receiving antenna is based on the fact that it is extremely reduced when it is housed in a metal exterior, and the reduction in output is reduced by using a non-metal back cover material. The purpose is to use the metal side with high texture.

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

  Therefore, in the past, the use of a large-sized high-sensitivity antenna structure or use only in areas where the electric field strength of radio waves is strong may impair the convenience of radio clocks and design the design. In addition, the manufacturing cost of the antenna structure is inevitably high.

  However, in such a wristwatch, even if it is possible to ensure the arrival of radio waves to the antenna, it is as if the back cover is made of a metal material with a thin metallic plating. However, in terms of appearance, there is a problem that there is no feeling of 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 lowered and the receiving performance is lowered.

  For this reason, in the past, a radio-controlled timepiece with a completely metallic exterior having a high-class feeling has not been realized.

  In other words, the background of the invention described above is that when the antenna is built in the watch, the back cover is made of a metal material, which is electrically conductive. Is based on the idea that the magnetic flux is absorbed by the back cover part and no radio wave reaches the antenna part.

  Therefore, in the past, since a highly sensitive antenna structure is used or it can be used only in a region where the electric field strength of radio waves is strong, the convenience of the radio timepiece is impaired and the design including the design is concerned. The manufacturing cost of the antenna structure is inevitably high.

  However, in a wristwatch that uses a non-metallic material for the back cover, even if it is possible to ensure the arrival of radio waves to the antenna, the back cover is treated as if it were metallic. This gives the user an impression as if the material is being used, but there is a problem that the image as a high-quality product is lost due to its appearance and lack of weight or texture.

  For this reason, in the past, a radio-controlled timepiece with a completely metallic exterior having a high-class feeling has not been realized.

Japanese Utility Model Publication No. 2-126408 Japanese Utility Model Publication No. 5-81787 International Publication WO95 / 27928 European Patent Publication No. 0382130 JP-A-11-64547 JP 2001-33571 A JP 2001-305244 A

  Accordingly, an object of the present invention is to solve the above-mentioned conventional problems, and to provide an antenna structure that can be used in a metal exterior that has good radio wave reception performance and is not subject to material or design restrictions. An object of the present invention is to provide a radio-controlled watch with a completely metal exterior using a structure.

  Another object of the present invention is to provide an antenna device for a wristwatch that prevents the bulkiness of the wristwatch from increasing in addition to the above-described purpose, and also provides a good feeling on the wrist when the present invention is applied to the wristwatch. To do.

In order to achieve the above-described object, the present invention basically employs a configuration as described below. That is, a first aspect of the present invention is an antenna structure that receives radio waves used inside a metal sheath, the antenna structure including a main magnetic path in which a coil is wound around a magnetic core, and the main magnetic path. The magnetic path is formed by a separate magnetic path that is separate from the magnetic path and has no coil wound around the magnetic core, and the magnetic path formed along the magnetic core forms a closed loop, and the main magnet The path has a bobbin that forms a coil, and the bobbin is made of a material different from that of the magnetic core, and a gap is provided between the main magnetic path and the sub magnetic path. The part is configured to have a magnetic resistance or permeability different from the magnetic resistance or permeability of the other part, and the bobbin is interposed in the gap part to set the width of the gap. With an antenna structure featuring That.

As a second aspect of the present invention, in the first aspect, the metal exterior includes a side part and a back cover part which are made of a metal material capable of accommodating the antenna structure therein. Or at least one member selected from a structure in which a side part and a back cover part made of a metal material capable of housing the antenna structure are integrally formed. Antenna structure.

Furthermore, a third aspect of the present invention is an antenna structure in which the main magnetic path and the sub magnetic path have different cross-sectional areas in the first or second aspect.

On the other hand, as a fourth aspect of the present invention, in the first aspect, the joint surface between the end surfaces formed between the main magnetic path and the sub magnetic path is formed in a tapered shape. Antenna structure.

  Since the radio-controlled timepiece having the antenna structure of the present invention employs the above-described technical configuration, the antenna has a simple configuration without significantly changing the structure or design of a conventional radio-controlled timepiece. Adopting the structure, the reception efficiency is good, the size and thickness of the watch itself is not different from the conventional one, the degree of freedom in design is increased, and the manufacturing cost can be kept low, A radio-controlled timepiece using the antenna structure can be easily obtained.

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

(First embodiment)
The configuration of one specific example of the antenna structure according to the first aspect of the present invention will be described below in detail with reference to the drawings.

  That is, as shown in FIG. 1, the antenna structure 2 in the specific example of the first aspect of the present invention is an antenna structure 2 that receives radio waves used inside the metal sheath 3 as described above. The antenna structure 2 includes a main magnetic path 21 in which a coil is wound around a magnetic core 6 and a sub magnetic path 22 including a sub magnetic path antenna core 9 'in which no coil is wound around the magnetic core. The magnetic path 12 that is configured and formed along the magnetic core 6 forms a closed loop, and a part of the magnetic path 12 of the antenna structure 2 that forms the closed loop The gap 10 is configured so that the part of the gap 10 has a magnetic resistance or permeability different from the magnetic resistance or permeability of the other part and can receive the external magnetic flux 4, but at the time of resonance Occurs during resonance Bundle 7 is the antenna structure 2 having a leak structure hardly outside is shown.

  Furthermore, in the antenna structure 2 according to the present invention, it is desirable that a material 1000 different from the material constituting the magnetic core 12 is disposed in the gap 10.

  Furthermore, in the antenna structure 2 according to the present invention, it is desirable that the magnetic resistance of the sub magnetic path 22 is larger than the magnetic resistance of the main magnetic path 21.

  Conventionally, as shown in FIG. 2, a metal sheath 103 having conductivity near the antenna structure 102 for receiving external radio waves or in contact with the antenna structure 102, for example, stainless steel, titanium alloy, etc. When a side used as an exterior of a watch and / or a back cover (hereinafter referred to as a metal exterior in the present invention) are arranged, the magnetic flux 104 by the external radio wave is applied to the metal exterior. In order to improve the sensitivity of the antenna structure 102, it is assumed that the antenna structure 102 itself is formed large. The antenna structure 102 is provided outside the metal sheath 103, or the exterior portion 103 is pushed instead of the metal sheath 103. Stick or to improve at the same time the appearance quality when configured with a ceramic, was walking painted thin metal plating or metallic in the non-metallic material surface.

  However, as a result of intensive studies, the inventors of the present application have found that the above-described conventional problem is actually an error and is in the vicinity of the antenna structure 102 or in contact with the antenna structure 102. Even when the metal sheath 103 having conductivity is present, the antenna structure 102 has substantially reached the external radio wave, and the problem is that, as shown in FIG. When the antenna structure 102 resonates, the magnetic force lines (magnetic flux) 107 emitted from the magnetic core portion 109 of the antenna structure 102 are drawn into the metal sheath 103, where an eddy current is generated and magnetic energy is lost. It has been found that there is a problem in that the Q value of the antenna is lowered, and as a result, the output from the antenna structure 102 is lowered and the reception performance is significantly lowered.

  The above problem will be described in more detail. For example, in FIG. 2, the watch exterior 103, that is, the side and the back cover are formed of a metal material, and the radio wave receiving antenna structure 102 is formed. When the radio wave 104 is arranged in the exterior portion 103 to receive radio waves, the flow of the magnetic flux 104 due to the external radio waves entering the watch 101 from the outside is somewhat attenuated (for example, about -3 dB). In effect, when the antenna structure 102 reaches the antenna structure 102 without any obstacle, receives the magnetic flux of radio waves, and the antenna structure 102 resonates, that is, energy state conversion is alternately performed between electric energy and magnetic energy. In the meantime, the magnetic flux flow 107 generated by the resonance output from the end of the magnetic core 109 in the antenna structure 102 becomes the exterior portion 103 made of the metal material. Then, it was found that eddy current is generated and the energy of the magnetic flux flow 107 generated by the resonance is absorbed, and as a result, the resonance output from the antenna structure 102 is reduced. Is.

  Here, with respect to the same antenna, in the resonance state and the non-resonance state, when the antenna is used alone and when the metal sheath is in the vicinity, the gain of the antenna and the resonance are obtained. The results measured for the Q value of the antenna are shown in Tables 1 and 2 below.

  In the above experiment, the material of the metal sheath is titanium (Ti), and the antenna structure is a conventional antenna in which a conductor is wound around a ferrite core for 400 turns. It was adjusted by performing the operation of attaching or removing.

The resonance frequency in this specific example is 40 KHz.
The measurement method in this experiment will be described later.

Table 1 Antenna gain
Antenna unit Metal exterior Attenuation rate (dB)
Resonance -31dB -62dB -32dB
Non-resonant -71.5dB -74.2dB -2.7dB

Table 2 Antenna Q-value Resonance 114 3 -31 dB
From the above results, when the antenna is non-resonant, the antenna receives the magnetic flux of the external radio wave and outputs a voltage amplitude according to the number of turns of the coil. Comparing the gain, it can be seen that at least about 70% (about −3 dB) of external radio waves are received even in the metal exterior.

  On the other hand, when the antenna is resonant, the gain is reduced by 32 dB when the metal sheath is present, in other words, the output of the antenna is reduced to about 1/40. When present, the single unit has a Q value of 114, but decreases to 3, and the reduction ratio shows a reduction of 31 dB, which is about 1/40.

  From the above results, it can be understood that the antenna output is remarkably decreased due to the decrease of the Q value in the metal exterior, and it does not mean that the external radio wave does not reach the interior of the exterior.

  Here, the Q value representing the characteristic of the resonant antenna will be described.

Figure 15 is a graph showing the relationship between the output frequency and the antenna, in FIG. 15, the frequency having the highest antenna output a resonance frequency f0.

Further, in FIG. 15 , the level indicated by A is a level that is about 3 dB (1 / √2) lower than the highest antenna output, and if the frequencies giving the output level 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 above Q value, the Q value indicates the degree of energy loss of the antenna in the resonance state. When the energy loss is small, the Q value becomes high, and the antenna output is substantially equal to the antenna output at non-resonance. Q value times that of.

  Looking at the relationship between the gain and the Q value when the antenna is alone in Table 1 and Table 2, the gain ratio of resonance / non-resonance is about 40 dB with respect to the Q value 114, which is 100 times when converted.

  That is, the higher the Q value, the better the antenna output, and the better the performance as an antenna structure.

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

  From the above, when the antenna is put in a metal exterior, it receives external radio waves and is in a resonance state, so that some energy loss is remarkably increased as compared with the antenna alone.

  As a result, the Q value is lowered and the output of the antenna is significantly lowered.

  Therefore, as a result of examining the cause of the energy loss in detail, it can be estimated that the magnetic flux generated by the resonance is sucked into the metal sheath and the energy of the magnetic flux is lost due to the vortex loss due to the interaction with the metal sheath.

  Therefore, by reducing the vortex loss, it is possible to suppress a decrease in the Q value and a decrease in the antenna output. To reduce the vortex loss, a sub magnetic path is provided in the antenna, and the magnetic flux generated by the resonance is supplied to the antenna. It is necessary not to leak outside the structure.

  Therefore, in the present invention, when the antenna structure 2 is arranged in contact with a metal material or arranged in the vicinity thereof, the Q value is lowered in order to ensure sufficient antenna output. As a result of studying how the antenna output can be suppressed by a reduction in the antenna output to a practically satisfactory level, the present invention has been reached. Basically, the antenna structure 2 for receiving radio waves is obtained. The antenna structure 2 has a structure of a magnetic path 12 that can receive the magnetic flux 4 generated by the external radio wave, but hardly leaks the magnetic flux 7 generated by the resonance at the time of resonance. The antenna structure is composed of a coil winding portion 21 (main magnetic path) in which a conductor 11 is wound and a coil is formed, and a non-coil winding portion 22 (sub magnetic path) in which the conductor 11 is not wound. By taking the body, Thus, it has been possible to easily manufacture an antenna structure suitable for electronic devices using radio waves, which is small, thin, and low in manufacturing cost. .

  That is, if the structure of the antenna structure 2 according to the present invention is described in more detail, in FIG. 1, the antenna structure 2 has an external radio wave when a predetermined radio wave arrives from the outside. Is received, but the magnetic flux 7 generated by resonance flows through the magnetic path 12 of the closed loop, and as a result, the antenna has a structure in which the magnetic flux 7 is difficult to leak out of the antenna structure 2. This is a structure 2.

  More specifically, the antenna structure 2 of the present invention includes a coil winding portion (main magnetic path) 21 in the magnetic path 12 and a non-coil winding portion (sub magnetic path) 22. It is desirable that at least a part is made of different materials.

  The coil winding portion 21 in the present invention constitutes a part of the above-described magnetic path 12, and an appropriate conductor 11 is provided on an appropriate core portion (main magnetic path antenna core portion) 9. A portion where the coil portion 8 is formed by being wound a number of times is defined, and the non-coil winding portion 22 in the present invention constitutes a part of the magnetic path 12 described above. In addition, the sub-magnetic path antenna core portion 9 ′, which is composed of an appropriate core portion, defines a portion where the coil of the conductor 11 is not wound.

  That is, the coil winding portion 21 in the present invention has a function such that when the antenna receives an external radio wave, the magnetic flux 4 generated by the external radio wave flows mainly to the coil winding portion 21. The non-coil winding portion 22 has a function such that the magnetic flux 7 generated while the coil winding portion 21 resonates mainly flows to the non-coil winding portion 22. It is what you have.

  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 function is exhibited, the portion is not coiled. Part.

  For example, if the coils are wound around both the coil winding part 21 and the non-coil winding part 22, if both the coils are resonated, the resonance phase of both coils shifts, so the output is In addition to the reduction, it is difficult to adjust the resonance frequency of both coils, and an increase in volume and the number of parts becomes a problem.

  On the other hand, in the above example, when the antenna of the coil winding part 21 on the output side is non-resonant, the coil resistance of the non-coil winding part 22 is added, and the copper loss in the resonance state is increased and the output is increased. Other volumes that decrease and an increase in the number of parts are also problematic.

  The coil winding portion 21 in the present invention is not limited to one coil, and a plurality of coils may be arranged.

  Furthermore, in the present invention, in order to prevent the reception of external radio waves with respect to the antenna structure 2, for example, the non-coil winding portion 22 is more effective than the effective permeability of the coil winding portion 21. The effective permeability is smaller than the magnetic path in the air through which the magnetic flux generated when the coil winding part 21 resonates when the non-coil winding part 22 does not exist is small. It is necessary to configure so that becomes large.

  Therefore, it is desirable that at least a part of materials constituting the coil winding part 21 and the non-coil winding part 22 are different from each other.

  On the other hand, in the present invention, the magnetic flux of the external radio wave that has entered the coil winding part 21 and the non-coil winding part 22 flows mainly on the coil winding part 21 side having a large effective permeability. An electromotive force is generated in the coil portion 8, and resonance occurs due to the electromotive force. The magnetic flux generated by the resonance is more than the effective magnetic permeability in the air than flowing from the coil winding portion 21 into the air. Since the non-coil winding portion 22 having a large effective magnetic permeability mainly flows, the magnetic flux leaking to the outside of the antenna structure is reduced as a result.

  Further, in this specific example, a part of the magnetic path of the antenna structure constituting the closed loop includes a part whose magnetic permeability is different from the magnetic permeability of other parts. In addition, a part of the magnetic path of the antenna structure constituting the closed loop includes a part whose magnetoresistance is different from that of other parts. It can also be configured as shown.

  For example, it is desirable that the magnetic resistance of the sub magnetic path 22 is configured to be larger than the magnetic resistance of the main magnetic path 21.

  Further, in the present invention, as shown in FIG. 1, the structure as described above is formed in a part of the magnetic path 12 corresponding to the non-coil winding portion 22 of the antenna structure 2 in the present invention. The effective magnetic permeability of the non-coil winding portion 22 is reduced by providing the gap portion 10 having a magnetic gap.

  On the other hand, when the antenna is installed outside the metal exterior as in the prior art or the exterior is made of plastic or ceramic and the antenna is built in, the gain and Q value of the antenna are as shown in Table 3 below. .

Table 3
Antenna alone When mounted on a watch Gain -31dB -40dB around (about 1/3)
Q value 114 around 40 (about 1/3)
According to the results of Table 3, in addition to the case where the antenna structure 102 is placed in contact with or in the vicinity of an object made of a metal material, the antenna structure 102 is replaced with a battery including a solar cell, a motor, a movement, a gear train, It has been found that the same problem occurs even when it is placed near an object made of a metal material such as a microcomputer, a heat sink, or a dial.

  Further, from the results in Table 3, when the characteristic (gain / output) level of the practical antenna at the conventional level is, for example, attenuation from about −31 dB to about −40 dB in terms of gain, various metals in the present invention are used. It is necessary to judge whether the antenna characteristics of the timepiece according to the present invention are within the practical range by comparing the antenna characteristics of the timepiece using the metal exterior using the material.

  That is, in the conventional radio-controlled timepiece, when the antenna is mounted on the timepiece, the practical reception performance target of the output of the antenna is not about -30 dB gain of the antenna alone but about -40 dB when the timepiece is mounted. The level is set as a reference target.

  3 and 4 show a comparison of the antenna characteristics of the conventional antenna and the antenna characteristics of the antenna in the present application by measuring various metal materials. In particular, in FIG. 3, the Q characteristics of the respective antennas are compared. FIG. 4 shows a comparison of measured gains as antenna characteristics of the conventional antenna and each antenna in the present application.

  The conventional antenna in FIGS. 3 and 4 uses a structure in which a conductor is wound around a straight ferrite core for 400 turns, and the structure of the antenna of the present invention is shown in FIG. A non-coiled winding portion 22 that is not wound with a coil is joined to the core portion of the coil winding portion 21 in which a conductor is wound 400 turns on a linear ferrite core, and a closed magnetic path is formed. A gap 10 formed by interposing a predetermined filler 1000 of 200 μm is provided in a part of the non-coil winding portion 22.

Also, the measurement of the attenuation factor of the gain and Q value of the antenna, as shown in FIG. 14, is measured by placing the antenna on a sheet made of various metal materials.

  That is, in FIG. 3, when there is no metal plate material of each antenna, the Q value and the plate material are brass (hereinafter referred to as BS), titanium (hereinafter referred to as Ti), and stainless steel (hereinafter referred to as SUS). In each case, the Q value is measured and the attenuation rate is expressed in dB. FIG. 4 shows the same data as in FIG. 3, the gain is measured, and the dB value is shown by an inverted bar graph. It is.

  As understood from the results of FIG. 3 and FIG. 4, it has been found that the decrease in the Q value and the decrease in the gain (antenna output) are the same for each metal plate material.

  Also, because of the plate material, it can be seen that the attenuation factor of the Q value is smaller by about 6 dB than when the metal exterior is used, compared with the results in Table 1.

  On the other hand, as can be seen from FIG. 4, it can be understood that the antenna gain (output) in the present invention is improved by about 10 dB (about 3 times) for each material in this evaluation sample.

  In the conventional antenna, as shown in Table 4, when contacting with BS, SUS and Ti, the decrease in gain was 1/4, 1/9 and 1/9, respectively. In this antenna, the gain of the antenna decreases by 1 / 1.2, 1 / 2.8, and 1 / 2.8, respectively, and it can be understood that significant improvement is achieved.

Table 4
Material Conventional antenna Antenna of the present invention BS 1/4 1/4
SUS 1/9 1 / 2.8
Ti 1/9 1 / 2.8
On the other hand, FIG. 5 is a graph showing the relationship between the antenna characteristics and the gap, and shows the relationship between the gap of the gap and the Q value.

  As can be understood from FIG. 5, the Q value of the antenna can be improved by adjusting the gap, and therefore the gain of the antenna can be improved. .

  Furthermore, in the present invention, it can be further improved by optimizing the number of turns (number of turns) of the conductor.

  As described above, even when the antenna structure 2 according to the present invention is in contact with the metal material 3 or the metal material 3 exists in the vicinity thereof, the reduction rate of the Q value is greatly increased. Practically, the antenna structure 2 that can exhibit good reception performance can be obtained easily and at low cost regardless of the presence or absence of the metal material.

  That is, in the present invention, when the metal material is in contact with the antenna structure or is present in the vicinity of the antenna structure, specifically, by increasing the Q value, By suppressing the decrease rate of the Q value, the gain of the antenna structure is improved, and by suppressing the decrease rate of the gain value, the reception characteristics of the antenna structure can be greatly improved. is there.

  As is clear from the above description, in the present invention, the permeability of a part of the magnetic path 12 of the antenna structure 2 constituting the closed loop is equal to the permeability of the other part. It is a preferred example that different parts are included.

  Further, in the present invention, a part of the magnetic path 12 of the antenna structure 2 constituting the closed loop includes a part whose magnetoresistance is different from that of other parts. It is also a desirable specific example.

  On the other hand, in the present invention, it is also desirable that the effective magnetic permeability of the non-coil winding portion 22 is configured to be smaller than the effective magnetic permeability of the coil winding portion 21.

  As another specific example of the antenna structure 2 in the present invention, the gap 10 is formed between the main magnetic path 21 and the sub magnetic path 22 as is apparent from FIGS. It is desirable that the gap 10 is formed in at least one of the joint portions, or the gap 10 is desirably formed in a part of the sub magnetic path 22.

  In the case of the above specific example, the joint surface between the end surfaces formed between the main magnetic path 21 and the sub magnetic path 22 or the gap portion 10 formed in the sub magnetic path 22 is shown in FIG. As shown, it is also preferable that the taper is formed.

  On the other hand, as another specific example of the antenna structure 2 according to the present invention, as shown in FIG. 1, the gap 10 is formed between the end surfaces of the main magnetic path 21 and the sub magnetic path 22 or the sub magnetic path. As shown in FIG. 7, the surfaces of the magnetic paths 12 in the portion 27 other than the end faces 13 of the sub magnetic path 22 are opposed to each other. The main magnetic path 21 and the sub magnetic path 22 may be arranged in parallel with each other in close proximity to each other. good.

  On the other hand, the joint surface 13 of the gap 10 provided in the secondary magnetic path 22 or the joint surface of the end faces 13 formed between the main magnetic path 21 and the secondary magnetic path 22 is shown in FIG. It may be formed in a tapered shape as illustrated.

  Furthermore, in the antenna structure according to the present invention, the gap 10 may be provided in a portion of the magnetic path 12 other than the vicinity of the coil winding portion 8 of the main magnetic path 21. good.

  In the present invention, it is desirable that a material 1000 different from the material constituting the magnetic core 12 is disposed in the gap.

Further, a specific example of the gap 10 in the present invention will be described . As shown in FIG. 16 (C), the gap 10 is provided in the non-coil winding portion 22. Alternatively, as shown in FIG. 16A or 16B , a gap 10 is formed in at least one joint 15 between the coil winding portion 21 and the non-coil winding portion 22. It may be a thing.

Furthermore, the gap 10, as shown in FIG. 16 (A) or (B), or may be provided in a portion of the magnetic path 12 other than the vicinity coil wound portion 21.

On the other hand, as shown in FIG. 16D, it is not preferable that at least a part of the gap 10 exists on the surface of the antenna structure 2 where the external radio wave reaches . As shown in (C), it is desirable that the gap 10 is 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. 16 (B), the antenna core portion 9 of the coil winding portion 21 has a radius of the antenna core from the central axis 28 of the portion extending outward from the coil portion. The gap 10 is configured such that the end face of the non-coil winding portion 22 is joined to a part of the surface opposite to the surface where the external radio wave reaches the central axis at a position separated by the length. Is preferably formed.

Furthermore, as shown in FIG. 16 (E), a magnetically altered layer, a nonmagnetic layer, or a layer having a low magnetic permeability is formed on the surface of at least a part of the non-coil winding portion 22 or the coil winding portion 21. It is also preferable that a film layer 80 made of is formed.

  In this case, the gap 10 is composed of only the film layer without an air layer.

  Here, the configuration of the gap in the present invention will be described in more detail.

  By the way, if the gap in the present invention is defined, the gap is composed of a nonmagnetic material or a magnetically altered layer having a low magnetic permeability and a nonmetallic material, and at least its main magnetic path is It is composed of a soft magnetic material.

Here, as the soft magnetic material, for example, ferrite,
A laminated composite material of amorphous metal soft magnetic material, a composite material in which cobalt or cobalt alloy soft magnetic powder is kneaded with resin, or the like is used.

  As described above, the width of the gap is an important point in the gap in the present invention.

  That is, if the gap is too wide or too narrow, the characteristics of the antenna structure are adversely affected, resulting in inconvenience as a product.

  That is, if the width of the gap provided in the sub magnetic path or between the main magnetic path and the sub magnetic path is too wide, the main magnetic path and the sub magnetic path cannot form a closed magnetic path in a sufficient shape. The amount of magnetic flux generated at resonance leaks around the antenna, and when the antenna is installed inside the metal sheath, the interaction between the magnetic flux leaking around the antenna and the nearby metal sheath (mainly considered to be vortex loss) As a result, energy loss is caused and the Q value of the antenna is lowered. As a result, the antenna output voltage is lowered, and the effect of the present invention cannot be fully exhibited.

On the other hand, when the main hoof and the sub magnetic path with a very small gap width are-
In other words, when the soft magnetic bodies that make up the main magnetic path and the secondary magnetic path are connected in a ring shape, the main magnetic path and the secondary magnetic path form a magnetically complete closed loop. However, the effective magnetic permeability of the antenna (in the example of the antenna used in the present application, when the secondary magnetic path is not provided, the relative magnetic permeability is about 20 to 30) is the softness that constitutes the main magnetic path and the secondary magnetic path. The magnetic material has a magnetic permeability (in the case of the manganese zinc ferrite used in this embodiment, the relative magnetic permeability is about 1000 to 2000), and the inductance of the antenna is proportional to the effective magnetic permeability of the antenna. It will become extremely large, about double to 100 times. When the inductance becomes extremely large,
Since the antenna has a parasitic capacitance in the coil section, the self-resonance frequency decreases drastically (decreases to a frequency of 1/5 to 1/10), and the resonance frequency is adjusted to the desired frequency (reception frequency) with an external resonance capacitor. Can no longer do.

Also, if the number of coil turns is reduced in order to reduce the inductance and increase the self-resonance frequency, the resonant local wave number can be adjusted to the desired frequency, but the number of coil turns must be reduced to one tenth, As a result, the antenna output voltage proportional to the number of coil turns decreases. Furthermore, when a completely closed loop is formed,
A large amount of magnetic flux of external radio waves entering the antenna flows toward the side of the sub-foundation road where the coil is not wound. As a result, the amount of magnetic flux contributing to the antenna output voltage is reduced and the antenna output voltage is lowered.
Even in this case, the effect of the present invention cannot be sufficiently exhibited.

  Therefore, it is necessary to control the width of the gap so as to have an appropriate value.

  In order to fully demonstrate the effect of the present invention, the amount of magnetic flux generated during resonance by adjusting the width of the gap of the secondary magnetic path leaks around the antenna to such an extent that the decrease in the antenna output voltage does not become a problem (metal Adjusting the resonance frequency to the desired frequency (reception frequency) with an external resonance capacitor at the same time as reducing the antenna output voltage reduction by installing the antenna in the exterior to 50% or less) Must be set so that the self-resonant frequency is higher than the desired frequency (reception frequency) so that the magnetic flux of the external radio wave entering the antenna flows to the main magnetic path side around which the coil is wound. . In other words, the magnetic resistance of the sub magnetic path including the gap is largely adjusted and set within an appropriate range with respect to the magnetic resistance of the main magnetic path.

From the result of trial manufacture and evaluation, this setting is 2 to 10 times the effective permeability of the antenna by providing a sub magnetic path, compared to the effective permeability of the antenna when the sub magnetic path is not provided.
It turned out that it is necessary to set it preferably 4 to 8 times. In other words, it is necessary to adjust and set the inductance of the antenna to 2 to 10 times, preferably 4 to 8 times by providing the sub magnetic path with respect to the inductance of the antenna when the sub magnetic path is not provided.

To make such settings, adjust the shape of the main magnetic path, a part of the sub magnetic path, or the shape of the gap provided between the sub magnetic path and the main magnetic path, and the magnetic characteristics of the members constituting the gap. You can set it.
More specifically, in this case, the setting in this case is to adjust the effective magnetic permeability or inductance of the antenna of the present invention so that the effective magnetic permeability or inductance of the antenna can be fully exhibited. It will be reasonably large. This can be done by increasing the size of the main magnetic path around which the coil is wound or increasing the number of turns of the coil, or from the magnetoresistive point of view. By changing the material of the member by narrowing the width or changing the magnetic properties of the member constituting the gap, particularly the relative permeability within the range of the magnetic permeability of the soft magnetic material constituting the main magnetic path and the sub magnetic path, etc. The effective magnetic permeability or inductance of can be greatly adjusted and set.

  However, in the case of an antenna used for a radio-controlled timepiece such as the antenna of the present invention, there is a limitation on the external dimensions because it needs to be housed in the watch exterior. Therefore, a method of narrowing the gap width without increasing the external dimension or adjusting the magnetic characteristics of the members constituting the gap is preferable.

In the case of the adjustment setting method by the width of the gap, in order to set and adjust the effective permeability or inductance so that the effect of the present invention is sufficiently exhibited,
When the opposing area is about several square mm, it is necessary to stably adjust and set the width of the gap to a dimension of 1 mm or less, preferably 0.2 mm or less, and simultaneously hold it. If the gap width is not adjusted and cannot be maintained stably, manufacturing variations in the reception characteristics (voltage output) of the antenna increase or change over time.

  Here, an example of a specific method for forming the above-described gap in the present invention will be described in detail.

  That is, as a first method, the position of the main magnetic path and the sub magnetic path is determined with an appropriate jig, the width of the gap is set, and in that state, an adhesive is poured into the gap portion and fixed and integrated.

For example, as shown in FIG. 18 , an appropriate adhesive or an appropriate fiber spacer or the like is mixed in one or both gaps of the joint portions 15 and 15 ′ of the main magnetic path and the sub magnetic path. It is possible to form the gap 10 by inserting 1000 such as an adhesive or double-sided adhesive tape.

Examples of the adhesive that can be used in the present invention include generally used organic adhesives such as epoxy adhesives, urethane adhesives,
Silicone adhesives, acrylic adhesives, nylon adhesives, cyanoacrylate adhesives, rubber adhesives, urea resin adhesives, melamine resin adhesives, vinyl adhesives, and the like can be used.

Next, as a second method for forming a gap, as shown in FIG. 6, an adhesive 1000 mixed with glass or resin beads having a uniform diameter or a fiber-like spacer filler cut shortly is used. ,
This is a method of fixing and integrating the gap width approximately equal to the diameter of the spacer used by applying and adhering to the surface forming the gap 15 or / and 15 'of the main magnetic path and the sub magnetic path. .

  Further, as a third method for forming the gap 10, a main magnetic path and a secondary magnetic path are formed by inserting a resin film 1000 having a constant thickness as a spacer into a cap portion and screwing or the like at an antenna installation position of a radio-controlled watch. Is fixed in a state of being abutted via a spacer, and the width of the gap is set.

  On the other hand, as a fourth method for forming the gap, the main magnetic path is formed by sandwiching a double-sided adhesive tape 1000 coated with an adhesive or adhesive on both sides between the opposing surfaces of the main magnetic path and the sub magnetic path. A method of setting the width of the gap by the thickness of the double-sided tape at the same time as fixing the sub magnetic path is also possible.

  In addition, as already described, the gap 10 may have a taper shape on the opposing surfaces of the main magnetic path and the sub magnetic path of the gap, and the gap 10 may be formed in the main magnetic path and the sub magnetic path. It may be provided at both of the two connection portions.

Next, when forming the gap in the present invention, when a ferrite-based sintered material such as manganese zinc-based ferrite is used as a soft magnetic material constituting the main magnetic path and the secondary magnetic path, the main magnetic path and the secondary magnetic path are formed. Even if the roads are in close contact, the behavior is different from the case of using a metal soft magnetic material such as magnetically annealed permalloy, and the relative permeability of the evaluation result of the ring-shaped evaluation sample: about 1000 to 2000 The effective permeability or inductance did not change, and the effective permeability or inductance increased by several to ten times depending on the shapes of the main magnetic path and the sub magnetic path.
As a result, in the case of ferrite-based sintered materials, an extremely thin magnetically altered layer with a magnetic permeability of several tens of μm that does not show the original magnetic properties for some reason, such as a deviation in composition from the chemical equivalent, on the surface of the member during sintering. It is considered that this deteriorated layer functions as a gap in the present invention.

In general, many soft magnetic materials exhibit structural sensitivity (of crystal structure). For example, in the case of permalloy, when rolling or cutting is performed, the crystal structure of the entire material or the surface in the vicinity of the cutting is disturbed and the magnetic properties are deteriorated. to degrade. For this reason, magnetic annealing must be performed after processing to remove the distortion of the crystal structure and restore the magnetic properties. In addition, it is well known that even in the case of ferrite, magnetic properties are deteriorated in the vicinity of the ground surface, and magnetic properties are deteriorated due to deviation from the chemical equivalent of the added metal.
A similar phenomenon is thought to have occurred.

For this reason, when the main magnetic path and the sub magnetic path are formed using a ferrite-based sintered material as the soft magnetic material, even if the main magnetic path 21 and the sub magnetic path 22 are brought into close contact with each other as shown in FIG. Although no gap is formed, the main magnetic path 21 and the sub magnetic path 22 are magnetically connected to each other through the magnetically altered layer 300 on the surface, and as a result, the magnetically altered layer 300 has the gap 10 of the gap 10. The width is set. Therefore, when a main magnetic path and a sub magnetic path are formed using a ferrite-based sintered material, the main magnetic path and the sub magnetic path are brought into close contact without forming a gap in appearance, and the main magnetic path and the sub magnetic path are brought into close contact with each other. The effective permeability or inductance can be adjusted by finely adjusting the area.

  In this case, as the setting of the gap width, the adhesive is applied and then abutted and fixed, or the adhesive is poured and adhered with a dispenser or the like in the abutted and fixed state.

  Furthermore, in the present invention, the coil winding part 21 and the non-coil winding part 22 may be configured to have different cross-sectional areas, and the coil winding part 21 and the non-coil winding part 22 may be different from each other. The winding part 22 forms an independent structure from each other. After the coil 8 is formed by winding the conductor 11 around the coil winding part 21, the coil winding part 21 and the non-coil winding part are formed. It is also possible to adopt a configuration in which 22 is integrated.

  As described above, even when the antenna structure 2 according to the present invention is in contact with the metal material or there is a metal material in the vicinity thereof, the reduction rate of the Q value and the gain value is greatly increased. Practically, the antenna structure 2 that can exhibit 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 kHz to several hundreds kHz.

  The metal sheath 3 in the present invention has a structure composed of a side part and a back cover part made of a metal material capable of accommodating the antenna structure 2 therein, or the antenna structure 2 It is desirable that the side portion and the back cover portion made of a metal material that can be housed therein are formed of at least one member selected from a structure in which the side portion and the back cover portion are integrally formed.

  On the other hand, the metal sheath 3 used in the present invention is specifically SUS, BS, Ti, Ti alloy, gold, silver, platinum, nickel, copper, chromium, aluminum, or alloys thereof. A metal sheathing material having the following conductivity is used.

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

  Further, in the present invention, specific examples of the metal casing 3 disposed in the vicinity of the antenna structure 2 include, for example, a clock casing including a back cover and a side, a dial, a motor, a movement, A battery, a solar battery (especially a SUS substrate solar battery), an arm band, a heat sink, and the like are included.

  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 Hured Packard (HP), a high-frequency probe (85024A) manufactured by Hured Packard (HP), and a transmission antenna (test loop 75Q, VQ-085F) of National (Matsushita Electric) Are connected as shown in FIG. 12 to form an antenna evaluation circuit, and the high-frequency probe (85024A) for connecting the antenna under measurement in the vicinity of the transmission antenna (test loop 75Q, VQ-085F) and the sample support section , And a predetermined antenna to be measured is set on the sample support, and then 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 connected to the high-frequency probe ( 85024A) and the network analyzer ( Those configured so as to a predetermined antenna rated at 195A).

In the evaluation apparatus, the distance between the antenna structure to be measured 2 and the transmission antenna (test loop 75Q, VQ-085F) is evaluated at a position 11 cm away from the lower end of the transmission loop antenna as shown in FIG. As shown in FIG. 15 , the measurement antenna structure 2 and the metal sheath 3 were brought into contact with each other and measured.

  In addition, the said metal exterior 3 used by this specific example used the board | plate material of 5 mm thickness of SUS, Ti, Ti alloy, and BS as the said metal material.

Further, in the above specific example, the frequency of the radio wave transmitted from the transmitting antenna (test loop 75Q, VQ-085F) is measured by changing in the range of 20 to 60 KHz when measuring a resonant antenna for 40 KHz. did.
A method for measuring the gain and Q value of the 40 KHz resonant antenna using the above measuring apparatus will be described with reference to FIG .

That is, the network analyzer (4195A) is swept from the transmitting antenna (test loop 75Q, VQ-085F) to a frequency of 20 to 60 KHz with a constant output, and the output of the antenna 2 to be measured is passed through the high-frequency probe (85024A). Monitor to obtain an output result as shown in FIG .

Here, the gain of the antenna is represented by the ratio of the input voltage amplitude to the transmission antenna and the output voltage amplitude of the antenna under measurement . In FIG. 15 , the highest antenna output frequency is the resonance frequency (f0), and the antenna output is The value of the ratio at the highest point was taken as the antenna gain.

  As described above, f1 and f2 were obtained from the measurement results, and the Q value was calculated.

  The results are shown in FIGS.

  In FIG. 3, the measurement results are shown in terms of attenuation rate (dB display) with reference to the Q value of a conventional antenna alone.

  As is apparent from the above experimental results, it is understood that the antenna structure 2 according to the present invention is a useful invention that clearly improves the conventional problems.

  FIG. 4 shows the gain in dB when the antenna structure according to the present invention and the conventional antenna structure shown in FIG. 2 are measured in the same environment as FIG. Even when the material is used, the gain is better than that of the conventional antenna.

  Furthermore, as shown in FIG. 5, the improvement of the Q value is dependent on the gap, and the narrower the gap, the larger the effective permeability of the non-coil winding portion 22, and the leakage flux decreases. The narrower the Q value, the better.

  However, since variations occur in the manufacturing process, it is important to manage the gap at a constant narrow interval.

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

  That is, the antenna structure 2 according to the present invention preferably has a configuration as shown in FIG. 1, for example. Specifically, the antenna structure 2 has a magnetic path 12 provided with a winding 11 as a coil. The constituting magnetic core <core part> 6 is extended and bent from both end parts, and its end parts 13 and 13 'are brought close to each other to form a loop-like magnetic path.

  In this specific example, it is desirable that a minute gap, that is, a gap 10 is provided in the facing portion 14 between the end portions of the magnetic core 6.

  As described above, the gap 10 includes an appropriate filler 1000 such as a resin film layer.

  In the gap 10 portion, the magnetic resistance is larger than the magnetic resistance in the magnetic path, and accordingly, a portion having a different magnetic resistance is formed in a part of the closed loop of the magnetic path (core 6) 12. .

  In the antenna structure 2 of the present invention, since it is a substantially loop-shaped antenna structure in which the gap 10 as described above exists, the magnetic flux entering from the outside enters from both ends of the antenna. Magnetic flux does not flow in a direction in which the gap 10 (magnetoresistance is medium), but flows to the winding portion 11 having a small magnetoresistance.

  As already described above, the winding section 11 affected by magnetism converts the magnetic flux change into a voltage, causes a resonance phenomenon by the L value of the antenna and the tuning capacitor capacity, and generates a magnetic flux due to the 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 12 of the antenna structure 2 forms a closed magnetic path, it is generated by resonance output from the antenna structure 2 when the antenna structure 2 resonates. As shown in FIG. 1, the flow of the magnetic flux 7 that flows mainly flows along the closed loop magnetic path 12, so that the antenna structure 2 is made of the metal material, for example, the exterior portion 3 The magnetic flux is prevented from leaking. Therefore, the magnetic flux leaking to the metal sheath 3 does not generate an eddy current and reduce the energy of the magnetic flux.

  As shown in FIG. 1, the magnetic path 12 (core 6) in the antenna structure 2 has a main magnetic path antenna core portion 9 of the coil winding portion 21 and a sub magnetic path antenna core of the non-coil winding portion 22. When both of the parts 9 'are integrated, when producing an antenna, the winding 11 is wound around the main magnetic path antenna core part 9 constituting the coil winding part 21 through the gap 10 or It is necessary to use the closed space formed between the coil winding part 21 and the non-coil winding part 22 to wrap around the main magnetic path antenna core part 9 constituting the coil winding part 21. Yes, productivity becomes worse.

  Therefore, when the main magnetic path antenna core portion 9 of the coil winding portion 21 and the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion 22 are separately provided and produced, the coil winding portion 21 is provided. At the stage of performing coil winding on the main magnetic path antenna core portion 9, the secondary magnetic path antenna core portion 9 ′ of the non-coil winding portion 22 is not attached, and after the winding operation is completed, the non-coil winding portion 22. By attaching the sub magnetic path antenna core portion 9 ′, it is possible to dramatically improve the winding production efficiency.

  That is, as shown in FIG. 6, in the present invention, the main magnetic path antenna core portion 9 of the coil winding portion 21 and the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion 22 are separated. The body is constructed so that both are joined after the winding operation is completed.

  In this case, the magnetic resistance of the non-coil winding portion 22 in the present invention is one of desirable examples that are configured to be larger 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 part 22 or, as shown in FIG. A gap 10 may be provided between the coil winding portion 21, that is, at least one of the joint portions 15 and 15 ′ at both end portions 23 and 23 ′.

  Furthermore, in another specific example of the present invention, it is also a preferable specific example that the coil winding part 21 and the non-coil winding part 22 have different cross-sectional areas.

  That is, as shown in FIG. 6, 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.

  As shown in the drawing, in the coil winding part 21, it is necessary to wind the winding 11 around the coil winding part 21, and therefore the winding is wound when the cross-sectional area of the coil winding part 21 is large. Later, the cross-sectional area also increases, and for example, the thickness of the watch is increased, which causes a problem that a thin watch cannot be manufactured.

  As shown in FIG. 6, in the antenna structure 2 according to the present invention, the coil winding part 21 and the non-coil winding part 22 form independent structures. After the coil 11 is wound around the coil winding part 21, the coil winding part 21 and the non-coil winding part 22 are joined and integrated.

  Further, as described above, the gap 10 is formed in at least one joint 15 between the coil winding part 21 and the non-coil winding part 22 of the antenna structure 2 in the present invention. The gap 10 formed between the coil winding part 21 and the non-coil winding part 22 is a joint surface 15 between the coil winding part 21 and the non-coil winding part 22 and the end faces. It is possible to fix a predetermined gap by inserting an appropriate filler 1000 into the.

  As shown in FIG. 5 described above, as is apparent from the change in the gain of the antenna with respect to the gap distance of the gap 10, there arises a problem that the gain varies depending on the gap gap distance.

Therefore, a bobbin, a spacer 17 or the like shown in FIG. 16 (E) is placed in the gap between the coil winding portion main magnetic path antenna core portion 9 and the non-coil winding portion 22 sub magnetic path antenna core portion 9 ′ . In addition, by interposing an appropriate film layer 80 or the like, an error in distance accuracy between the gaps 10 becomes a dimensional accuracy error in foreign matters such as protrusions or spacers of the bobbin, and the antenna gain can be stabilized. It becomes.

  In the antenna structure 2 according to the present invention, the joining surface 15 between the end surfaces 19 formed between the coil winding portion 21 and the non-coil winding portion 22 is formed in a tapered shape. It is desirable that

  That is, the joint surface 15 between the end surfaces 19 constituting the gap 10 formed between the coil winding portion 21 and the non-coil winding portion 22 is formed in an oblique state 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 is adjusted with respect to the main magnetic path antenna core portion 9 ′ of the coil winding portion and the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion. It can be easily adjusted by moving in the direction of pushing or pulling out.

  Furthermore, in such a configuration, as described above, variations in antenna gain are caused by the main magnetic path antenna core portion 9 of the coil winding portion 21 and the sub magnetic path antenna core portion 9 of the non-coil winding portion 22. The contact area of the gap is increased because the rate of change of the gain of the antenna with respect to the gap distance is relaxed if the contact area of the gap increases. Is more advantageous.

  That is, by configuring as in the present specific example, the contact area of the gap portion can be increased by √2 times compared to being parallel to the winding portion 11, so that variations in antenna gain can be reduced. It becomes.

  In FIG. 6, reference numeral 18 denotes a winding frame when winding the winding 11 around the main magnetic path antenna core portion 9 of the coil winding portion 21, and 20 denotes an antenna core of the coil winding portion 21. The insulating material inserted between the said main magnetic path antenna core part 9 and the coil | winding 11 is shown, when is electrically conductive.

  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 the portion other than the end surfaces of the non-coil winding portion 22. These surfaces may be formed to face each other.

  That is, as shown in FIG. 7A, when the gap 10 is formed in a part of the main magnetic path antenna core portion 9 ′ of the non-coil winding portion 21, the non-coil winding is performed. Except for the end faces 13 of the non-coil winding part 22, at least a part of the end parts 13 overlap each other without facing the mutually facing end parts 13 of the sub magnetic path antenna core part 9 ′ of the part 22. 7 may be formed so that the surfaces 26, 26 'of each magnetic path face each other, or as shown in FIG. 7B, the antenna of the coil winding part 21 In the case where the gap 10 is formed between the end surface 19 of the co-section 9 and the end surface 19 ′ of the sub magnetic path antenna core section 9 ′ of the non-coil winding section 22, the end sections 19 are opposed to each other. Without overlapping each other at least a part of the non-coil winding portion 22 The surface 19 'portion 27 other than' the portion 27 other than the end face 19 of the coil winding portion 21 may be one that is formed to face.

  Further, as shown in FIG. 7C, the coil 100 formed on the air core coil or bobbin and the two antenna cores 200, 201 formed in an L shape are opposed to each other and formed on the air core coil or bobbin. The structure may be such that the coil 100 is inserted separately from both ends of the coil 100 into the center thereof and a part of both is arranged to face each other.

  On the other hand, in the structure of the antenna structure 2 in the present invention, both side portions 23 of the portion constituting the main magnetic path antenna core portion 9 of the coil winding portion are tapered or formed as shown in FIG. A curved surface formed by an appropriate curve or broken line may be formed.

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

  Furthermore, in the present invention, the cross-sectional area or thickness of the secondary magnetic path antenna core 9 ′ of the non-coil winding portion in the antenna structure is the same as that of the main magnetic path antenna core 9 of the coil winding portion. It is also a preferred specific example that it is configured to be larger or thicker than the area or thickness.

  As described above, in order to reduce the magnetic resistance between the main magnetic path antenna core portion 9 of the coil winding portion and the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion, It is desirable that the main magnetic path antenna core portion 9 and the sub magnetic path antenna core portion 9 'of the non-coil winding portion are thicker or larger in cross-sectional area. Since the winding part 11 is provided, if the cross-sectional area or the thickness of the main magnetic path antenna core part 9 of the coil winding part is large or thick, the thickness of the antenna structure 2 is increased accordingly. End up. However, the secondary magnetic path antenna core portion 9 ′ of the non-coil winding portion has no winding portion 11, and therefore the thickness of the winding portion is larger than that of the main magnetic path antenna core portion 9 of the coil winding portion. It becomes possible to increase the thickness or the cross-sectional area.

  By adopting such a configuration, the magnetic resistance value between the main magnetic path antenna core portion 9 of the coil winding portion and the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion is reduced and generated by resonance. A larger amount of magnetic flux can be guided to the sub-magnetic-path antenna core portion 9 ′ of the non-coil winding portion, and variations in antenna gain can be suppressed.

  And preferably, the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion is disposed inside the main magnetic path antenna core portion 9 of the coil winding portion with respect to the traveling direction of the radio wave, In such a form that the main magnetic path antenna core portion 9 of the coil winding portion covers the sub magnetic path antenna core portion 9 'of the non-coil winding portion, the radio wave directly passes through the sub magnetic path of the non-coil winding portion. It is configured not to reach the antenna core portion 9 ′.

  That is, in this specific example, the coil winding portion of the antenna structure is disposed on the outer peripheral edge portion of the radio wave correction timepiece, and the non-coil winding portion is the outer peripheral edge portion of the radio wave correction timepiece. On the other hand, it is desirable that the coil is disposed inside the coil winding portion.

  Therefore, when the main magnetic path antenna core portion 9 of the coil winding portion constituting the antenna structure 2 is mounted on a wristwatch or the like, it is disposed on a portion where the watch is likely to receive radio waves directly on average. In addition, it is desirable to arrange the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion on the side opposite to the surface of the coil winding portion main magnetic path antenna core portion 9 to which the radio wave hits.

  That is, the magnetic flux that has entered the main magnetic path antenna core portion 9 of the coil winding portion does not flow in the direction of the sub magnetic path antenna core portion 9 ′ of the non-coil winding portion where the gap 10 exists, Contrary to the small winding portion 11, conversely, the magnetic flux that has entered the secondary magnetic path antenna core portion 9 ′ of the non-coil winding portion is also the secondary magnetic path antenna core portion 9 ′ of the non-coil winding portion with the gap 10. Does not flow.

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

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

  The specific structure of the antenna structure 2 in the above-described antenna structure 2 according to the present invention is as shown in FIG. 6, and the main magnetic path antenna core portion 9 of the coil winding portion is entirely configured. Further, it is designed so as to cover the sub magnetic path antenna core portion 9 'of the non-coil winding portion.

  As another aspect of the present invention, as shown in FIG. 8, the reference signal generating means 31 for outputting the reference signal, the time measuring means 32 for outputting the time information based on the reference signal, and the time information are provided. Display means 33 for displaying the time, receiving means 34 for receiving a standard radio wave having reference time information, and output time correcting means for correcting the output time information of the time measuring means based on the received signal from the receiving means 34 In the radio-controlled timepiece 1 constituted by 35, the receiving means 34 is the radio-controlled timepiece 1 composed of 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 the wristwatch in use to the standard time. It is what

  If a specific example of the radio-controlled timepiece 1 according to the present invention is shown in FIG. 9, the radio-controlled timepiece 1 has an antenna structure 2 having a configuration as shown in FIG. However, the main magnetic path antenna core portion 9 of the coil winding portion of the antenna structure 2 is positioned in the vicinity of the outer edge portion 51 so that the sub magnetic path antenna core portion 9 of the non-coil winding portion is located. A configuration in which 'is arranged on the side opposite to the outer edge portion 51 of the timepiece with respect to the main magnetic path antenna core portion 9 of the coil winding portion is shown.

  In FIG. 9, 52 is a receiving IC, 53 is a filter crystal resonator, 54 is a 32 KHz crystal resonator, 55 is a gear train, 56 is a crown, 57 is a back-around mechanism, 58 Is a first converter (motor), 59 is a battery, and 40 is a microcomputer constituting an arithmetic processing unit including time measuring means or time adjusting means.

  FIG. 10 shows another specific example of the radio-controlled timepiece 1 according to the present invention in which the configuration of FIG. 9 is partially changed. The difference from FIG. 9 is shown in FIG. In addition to the first converter (motor) 58, a second converter (motor) 41 is provided separately.

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

  Of course, the arrangement configuration example of the radio-controlled timepiece 1 of FIGS. 9 and 10 shows an example. As described above, the antenna structure 2 according to the present invention is a conductive object made of a metal material. Since the influence of the presence is small, the relationship with the arrangement configuration of other parts is flexible, so that many variations are conceivable.

  In another specific example of the present invention, as shown in FIG. 11, the antenna structure 2 is provided with a windshield 43 with respect to the dial 46 of the radio-controlled timepiece 1. It is also a desirable mode that it is provided on the opposite surface.

  In FIG. 11, 44 is a conductive exterior portion made of a metal material, and 45 is an hour / minute hand constituting the display means.

  In the first specific example of the present invention, the configuration as described above is adopted, so that the problems of the prior art described above are solved and the structure, exterior material, or design of the conventional radio wave correction watch is solved. Adopting an antenna structure with a simple configuration without significantly changing etc., the reception efficiency is good, the size and thickness of the watch itself is not different from the conventional one, and the degree of freedom in design is increased It is possible to easily obtain the antenna structure and the radio wave correction timepiece using the antenna structure, which can increase the manufacturing cost at a low cost.

  Furthermore, even when an antenna is housed in a metal exterior, a radio-controlled timepiece having a high commercial value that does not cause a decrease in gain can be easily obtained.

  Since the present invention employs the configuration as described above, the antenna has a simple configuration without solving the above-described problems of the prior art and without significantly changing the structure or design of the conventional radio-controlled timepiece. An antenna that adopts a structure, has good reception efficiency, has the same size and thickness as the wristwatch itself, has increased design freedom, and can be manufactured at low cost. A radio wave correction timepiece using the structure and the antenna structure can be easily obtained.

FIG. 1 is a diagram showing a configuration of a specific example of an antenna structure according to the present invention. FIG. 2 is a cross-sectional view showing a configuration in a specific example of a conventional antenna structure. FIG. 3 is a graph showing the attenuation factor of the Q value due to the influence of the metal plate of the antenna structure according to the present invention and the related art. FIG. 4 is a graph showing a change in gain due to the influence of the metal plate of the antenna structure according to the present invention and the related art. FIG. 5 is a graph showing a change state of the gap distance and the Q value when the antenna structure according to an embodiment of the present invention is used. FIG. 6 is a plan view showing a specific example of the configuration of the antenna structure according to the present invention. FIG. 7 is a diagram illustrating a configuration example of the gap portion in the antenna structure according to the present invention. FIG. 8 is a block diagram showing an example of the configuration of the radio-controlled timepiece according to the present invention. FIG. 9 is a diagram showing a specific example of the arrangement configuration of each component in the radio-controlled timepiece according to the present invention. FIG. 10 is a diagram showing another specific example of the arrangement configuration of each component in the radio-controlled timepiece according to the invention. FIG. 11 is a diagram showing another specific example of the arrangement configuration of each part in the radio-controlled timepiece according to the present invention. FIG. 12 is a diagram for explaining a specific example of the antenna gain and Q value measuring method according to the present invention. FIG. 13 is a diagram for explaining a specific example of the antenna gain and Q value measuring method according to the present invention. FIG. 14 is a diagram for explaining a specific example of the antenna gain and Q value measuring method according to the present invention. FIG. 15 is a diagram for explaining a specific example of the antenna gain and Q value measuring method according to the present invention. FIG. 16 is a diagram for explaining an example of the configuration of the antenna structure according to the present invention. FIG. 17 is a diagram showing the configuration of another specific example in the antenna structure of the present invention. FIG. 18 is a diagram showing the configuration of another specific example in the antenna structure of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Radio wave correction watch 2,102 Antenna structure 3,103 Exterior part, metal exterior 4,104 Magnetic flux 6, 109 Magnetic core 7, 107 Magnetic field line (magnetic flux) by an external radio wave
8, 108 Coil portion 9 Main magnetic path antenna core portion 9 'Sub magnetic path antenna core portion 10 Gap 11, 111 Conductor, winding 12 Magnetic path 13, 13' Magnetic path end 14 Opposing portions 15, 15 between ends 'Joint 16 bobbin
17 Spacer 18 Fixing pin 19 End surface 20 Insulating material 21 Main magnetic path 22 Sub magnetic path 23 Both side portions 26, 26 'Surface portion 27 other than end surface of antenna core portion, 27' Surface portion 28 other than end surface of antenna core portion Antenna core Central axis 31 of the unit Reference signal generating means 32 Timing means 33 Display means 34 Receiving means 35 Time information correcting means 40 Arithmetic processing section, microcomputer 41 Second converter (motor)
42, 44 Metal exterior 43 Glass draft shield 46 Dial 45 Hour and minute hands 51 Clock outer edge 52 Receiver IC
53 Filter Crystal Resonator 54 32KHz Crystal Resonator 55 Train Wheel 56 Crown 57 Back Around Mechanism 58 First Converter (Motor)
59 Battery 80 Film layer 100 Coil 200, 201 Antenna core 1000 Filler

Claims (7)

An antenna structure for receiving radio waves used inside a metal exterior,
The antenna structure is composed of a main magnetic path in which a coil is wound around a magnetic core, and a sub magnetic path in which the coil is not wound around the magnetic core separately from the main magnetic path,
And the magnetic path formed along the magnetic core forms a closed loop,
The main magnetic path has a bobbin forming a coil, and the bobbin is made of a material different from a material constituting the magnetic core,
A gap is provided between the main magnetic path and the sub magnetic path,
The gap portion is configured to have a magnetic resistance or permeability that is different from the magnetic resistance or permeability of the other part,
The antenna structure is characterized in that the bobbin is interposed in the gap to set the width of the gap.   The metal exterior is composed of a side part and a back cover part made of a metal material capable of accommodating the antenna structure therein, or a metal material capable of accommodating the antenna structure therein. 2. The antenna structure according to claim 1, wherein the antenna structure is formed of at least one member selected from a structure in which the side portion and the back cover portion are integrally formed. 3. The antenna structure according to claim 1, wherein the main magnetic path and the sub magnetic path have different cross-sectional areas.   The antenna structure according to claim 1, wherein the gap is formed in at least one joint portion between the main magnetic path and the sub magnetic path.   The antenna structure according to claim 1, wherein a joint surface between end faces formed between the main magnetic path and the sub magnetic path is formed in a tapered shape. The gap is characterized in that the end surfaces of the main magnetic path and the sub magnetic path, or the surfaces of the magnetic paths in portions other than the end faces of the sub magnetic path are opposed to each other. The antenna structure according to any one of claims 1 to 5 . The gap in any one of claims 1 to 6, characterized in that at least a part of said main magnetic flux path and the secondary magnetic path is formed in a portion disposed in a parallel state in close proximity to each other The antenna structure described.

Images