JP2004294258A - Radiowave timepiece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radiowave timepiece for receiving radiowave while using an antimagnetic plate and holding prescribed time accuracy even in an environment where external magnetism is encountered. <P>SOLUTION: A timepiece casing 12 of this radiowave timepiece is stored with an antenna 32, a movement 24, and the antimagnetic plate 38. The plate 38 has an opening part 38b. The antenna 32 and the plate 38 are positioned so that the antenna 32 confronts the opening part 38b in the plate 38 or the antenna 32 projects partly or wholly out of the opening part 38b. This enables the antenna 32 to receive radiowave without being affected by the plate 38. Accordingly, a timepiece device can be protected from external magnetism even for the radiowave timepiece without lowering its radiowave reception performance. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a radio-controlled timepiece that receives a predetermined radio wave including time information and displays the time, and in particular, a case of a radio-controlled timepiece that aims to improve the radio wave reception performance and improve the anti-magnetic performance against external magnetism. It is about structure.
[0002]
[Prior art]
In general, in the case of a timepiece that drives a hand by a motor, the driving of the hand is affected by external magnetism, and the accuracy of the timepiece may be reduced. For this reason, an anti-magnetic plate for blocking external magnetism is provided in the watch case to maintain the watch accuracy.
[0003]
FIG. 8 is a sectional view showing the structure of a wristwatch in which a magnetic-resistant plate for preventing the influence of external magnetism as described above is provided between a middle frame holding a movement and a back cover. In this structure, a middle frame 6 for fixing the movement 4 is provided inside the case 2, and an upside-down U-shaped anti-magnetic plate 10 is attached to the back cover 8 side of the middle frame 6 so as to surround the movement 4. (See Patent Document 1).
[0004]
The anti-magnetic plate 10 is fixed to the module by screws or bite-fixed as described above, or is fixed between the core 8a of the back cover 8 and the inner frame 6, or an adhesive is attached to the inner surface of the back cover 8. And fixed by a fixing structure according to the space in the watch case, the structure of the module, and the like.
[0005]
[Patent Document 1]
Japanese Utility Model Registration No. 2505967
[Problems to be solved by the invention]
The above anti-magnetic measures are required for maintaining the clock accuracy even in a radio-controlled timepiece having the same structure as a general timepiece with respect to driving the hands. However, a radio-controlled timepiece receives a standard radio wave (carrier) containing time information, extracts time information from the radio wave to obtain and display the correct time, and uses a magnetic-resistant plate to block external magnetism. When the movement is surrounded, there is a possibility that the reception performance is reduced. For this reason, it has not been possible to use a magnetic-resistant plate in a radio-controlled timepiece.
[0007]
The present invention has been made in view of the above-described problems of the related art, and even when using a watch case in which a magnetic-resistant plate is disposed inside the case, it is possible to receive a radio wave including predetermined information such as time information, Another object of the present invention is to provide a radio-controlled timepiece that can maintain a predetermined time accuracy even in an environment with external magnetism.
[0008]
[Means for Solving the Problems]
According to a radio timepiece of the present invention, as described in claim 1, an antenna, a timepiece device, and an anti-magnetic plate are housed in a watch case, and the anti-magnetic plate disposed in the watch case is provided at a portion facing the antenna. It has an opening. Further, as set forth in claim 2, the antenna includes a magnetic core material and a plurality of coils wound around the magnetic core material, and the antenna extends along at least one plane including an axis of the magnetic core material. An opening is provided in the anti-magnetic plate on which the antenna is projected in parallel. Further, as set forth in claim 3, the antenna includes a magnetic core material and a plurality of coils wound around the magnetic core material, and at least an opening is formed in the anti-magnetic plate opposed to at least an end of the antenna. It is provided. Further, as set forth in claim 4, the antenna is disposed outside the anti-magnetic plate (the side other than the clock device side). As set forth in claims 5 to 7, at least a part of the antenna protrudes from an opening of the anti-magnetic plate and is located on the inner side of the body of the watch case, or a back cover of the watch case. Side or the display panel side. Further, as described in claim 8, the magnetic-resistant plate is made of pure iron or permalloy (YUS material, ferritic stainless steel such as SUS430). Further, a non-magnetic member having an electric resistivity of 7.0 μΩ-Cm or less is provided on the inner surface (timepiece side) of the magnetic-resistant plate. Further, the non-magnetic member is disposed in an opening of the magnetic-resistant plate. Further, as described in claim 11, the non-magnetic member is made of at least one of copper, aluminum, magnesium, zinc, silver, gold or an alloy thereof. Further, as set forth in claim 12, the non-magnetic member has a rising portion rising in the direction of the display panel, and the rising portion contacts a part of the timepiece case, and The rotation is regulated.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, the antenna, the timepiece device, and the anti-magnetic plate are housed in a watch case, and the anti-magnetic plate is provided with an opening. The opening of the anti-magnetic plate is provided at a position facing the antenna to prevent the receiving performance of the antenna from being reduced. Also, the antenna and anti-magnetic plate must be positioned so that the antenna faces the opening of the anti-magnetic plate, or part or all of the antenna can protrude from the opening to receive radio waves without being affected by the anti-magnetic plate. It is positioned so that it can be. This makes it possible to protect the timepiece device from external magnetism even in a radio timepiece without deteriorating the radio wave reception performance.
[0010]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a radio-controlled timepiece according to a first embodiment of the present invention, and FIG. 2 is a plan view of the anti-magnetic plate 38 shown in FIG. The watch case 12 in this embodiment includes a body 14, a back cover 16, and a glass 18. The body 14 has a substantially cylindrical shape, a glass 18 is attached via a packing 20 to a step portion 14a at the inner peripheral edge of the upper opening in the figure, and the back cover 16 is press-fitted into the lower opening in the figure. It is attached by means such as screwing and screws. The back cover 16 shown in FIG. 1 is attached to the body 14 by press fitting, and a packing 22 is sandwiched between a rising portion 16a thereof and an inner side surface 14c of the body 14.
[0011]
A movement 24 including a radio-controlled timepiece receiver, a CPU, a display drive unit, and the like is housed in the body 14. Above the movement 24 in the figure, a dial 26 serving as a time display unit and hands 28 are provided. The movement 24 is positioned by the dial 26 abutting against the lower surface in the figure of the inwardly protruding portion 14 b forming the step portion 14 a of the body 14, and a resin disposed on the upper surface of the rising portion 16 a of the back cover 16. It is fixed by being sandwiched between the middle frame 30. A predetermined space is provided between the movement 24 and the back cover 16, and an antenna 32 is disposed in the space. The antenna 32 includes a rod-shaped magnetic core 34 made of a ferrite material or the like, and a coil 36 wound around the magnetic core 34, and is fixed to the lower surface of the movement 24.
[0012]
Further, in the present embodiment, a magnetic-resistant plate 38 is provided in the space between the movement 24 and the back cover 16. The anti-magnetic plate 38 is made of ferritic stainless steel (for example, SUS430), and has a circular shape whose planar shape approximates the planar shape of the movement 24 as shown in a plan view from the back cover direction in FIG. In addition, the cross section has an upward U-shape, and has a rising portion 38a on the outer peripheral portion. The anti-magnetic plate 38 in the present embodiment is fixed to the movement 24 by fixing the tip end of the rising portion 38a to the movement 24 by biting or screwing.
[0013]
An opening 38b is provided in the anti-magnetic plate 38. The opening 38 b is provided so as to be located at a portion facing the antenna 32 when the magnetic-resistant plate 38 is attached to the movement 24. In the case of the present embodiment, the antenna 32 is arranged at the corner of the lower surface of the movement 24 so that the axis of the magnetic core 34 is oriented in the direction perpendicular to the front and back directions of the timepiece. For this reason, the opening 38 b of the magnetically permeable plate 38 is provided at a portion where the antenna is projected onto the magnetically permeable plate 38 so as to be parallel to a plane including the axis of the magnetic core 34 of the antenna 32. The internal size of the opening 38 b is set equal to or slightly larger than the external size of the antenna 32.
[0014]
In the radio timepiece having the above-described configuration, the CPU in the movement 24 operates the display driving unit based on the standard radio wave received by the antenna 32 to drive the hands 28 so that the hands 28 are always corrected. At this time, in the present embodiment, the movement of the hands is not affected by the external magnetism since the movement 24 is surrounded by the anti-magnetic plate 38. In addition, since the anti-magnetic plate 38 has the opening 38b, the antenna 32 is opened in the direction of the back cover 16, so that the radio signal can be received without being blocked by the anti-magnetic plate 38.
[0015]
FIG. 3 is a sectional view of a radio-controlled timepiece according to a second embodiment of the present invention. The second embodiment has the same basic configuration as the structure of the watch case 12 and the anti-magnetic plate 38 as in the first embodiment, and the positional relationship between the anti-magnetic plate 38 and the antenna 32 is different from that of the first embodiment. Here, this different point will be described in detail. In the second embodiment, a magnetic-resistant plate 38 made of pure iron is assembled to the lower portion of the movement 24 so as to be in contact with the lower surface of the movement 24. At this time, the antenna 32 protrudes from the opening 38 b of the magnetically permeable plate 38 toward the back cover 16 and is positioned outside the magnetically permeable plate 38. For this reason, the antenna 32 is located at a place not surrounded by the magnetic-resistant plate 38, and can receive a radio signal without being affected by the magnetic-resistant plate 38.
[0016]
In the second embodiment, since there are many portions where the anti-magnetic plate 38 and the movement 24 are in contact with each other, the anti-magnetic plate 38 can be bonded and fixed to the movement 24 using an adhesive.
[0017]
FIG. 4 is a sectional view of a radio-controlled timepiece according to a third embodiment of the present invention. The third embodiment is similar to the first embodiment in the basic configuration such as the timepiece case 12 and the positional relationship between the anti-magnetic plate 38 and the antenna 32, and differs from the first embodiment in that a non-magnetic member 40 is provided. Since it is different, the non-magnetic member 40 will be described in detail. The non-magnetic member 40 is made of a metal material having an electric resistivity of 7.0 μΩ-cm or less, such as gold, silver, copper, brass, aluminum, magnesium, zinc, or an alloy thereof. In the example, a plate-shaped copper material is used. The magnetically permeable plate 38 is made of a YUS material (cladding material), and is located between the movement 24 and the back cover 16 as in the first embodiment, and the antenna 32 is located closer to the movement 24 than the magnetically permeable plate 38 is. It is arranged to be located. The non-magnetic member 40 is disposed between the above-described anti-magnetic plate 38 and the antenna 32, and in this embodiment, is mounted on the inner surface of the anti-magnetic plate 38 facing the antenna 32. By providing the non-magnetic member 40 so as to face the antenna 32 or by providing the non-magnetic member 40 in the vicinity of the antenna, it has been experimentally confirmed that the reception gain of the radio signal is improved by about 2 to 3 dB. Has been confirmed. Further, the nonmagnetic member 40 of the present embodiment is provided with an opening 40b at a position corresponding to the opening 38b of the anti-magnetic plate 38, and has a structure that does not hinder reception of a radio signal as in the anti-magnetic plate 38. ing.
[0018]
Further, the non-magnetic member 40 can be subjected to a surface treatment such as plating in order to prevent corrosion, and no reduction in receiving sensitivity due to the surface treatment was observed.
[0019]
FIG. 5 is a sectional view of a radio-controlled timepiece according to a fourth embodiment of the present invention. The fourth embodiment has the same basic structure as the first embodiment, such as the timepiece case 12 and the positional relationship between the magnetically-resistant plate 38 and the antenna 32. The non-magnetic member 42 is provided in the opening 38b of the magnetically-resistant plate 38. Since the provided points are different from the first embodiment, the different points will be described in detail. The non-magnetic member 42 is made of a metal material having the same electrical resistivity of 7.0 μΩ-cm or less as in the above-described third embodiment. In this embodiment, a non-magnetic member made of brass is used. Further, the anti-magnetic plate 38 in this embodiment is made of ferritic stainless steel (for example, SUS430), and is disposed between the movement 24 and the back cover 16 as in the first embodiment described above. An opening 38b is provided at a position facing the attached antenna 32. The non-magnetic member 42 is attached to the opening portion 38b of the anti-magnetic plate 38 by caulking, brazing, bonding, or the like, and faces the antenna 32. By providing the non-magnetic member 42 in this way, the disturbance of the resonance phenomenon near the antenna is reduced, the receiving sensitivity is improved, and the receiving gain of the radio signal is improved by about 2 to 3 dB.
[0020]
The non-magnetic member 42 can be subjected to a surface treatment such as plating, similarly to the non-magnetic member 40 in the third embodiment, and no decrease in the receiving sensitivity due to the surface treatment is observed. Was.
[0021]
FIG. 6 is a sectional view of a radio-controlled timepiece according to a fifth embodiment of the present invention, and FIG. 7 is a plan view of the anti-magnetic plate 38 shown in FIG. The fifth embodiment has the same basic structure as the first embodiment, such as the watch case 12, the positional relationship between the magnetically deflectable plate 38 and the antenna 32, and the like. The difference between the first embodiment and the point that the fixing of the fixing member 38 is fixed by sandwiching it between the upper surface of the rising portion 16a of the screw-type back cover 16 and the lower surface of the movement 24 will be described in detail. The anti-magnetic plate 38 is provided with a rising portion 38a surrounding the movement 24. In the present embodiment, the notch 38c is provided in a part of the rising portion 38a, and the notch 38c is fitted into the inner end of the side pipe 44 that penetrates the body 14, thereby stopping the rotation of the anti-magnetic plate 38. It is configured so that it can be easily positioned. In addition, in order to fix the back cover 16 to the body 14 with screws, the anti-magnetic plate 38 on the upper surface of the rising portion 16a of the back cover 16 may be rotated. The rotation of the anti-magnetic plate 38 can also be prevented.
[0022]
The material of the watch case 12 including the body 14, the back cover 16 and the like in each of the above embodiments may be any material such as stainless steel or plastic as long as it is suitable for a radio timepiece.
[0023]
Further, in each of the above embodiments, the antenna 32 is disposed at the corner of the lower surface of the movement 24 so that the axis of the magnetic core 34 is oriented in the direction orthogonal to the front and back directions of the timepiece. In consideration of the characteristics, the antenna 32 is arranged so that the outer surface of the end of the antenna 32 and the inner surface of the body 14 or the inner surface of the back cover 16 are parallel, or one end surface of the antenna 32 is It is also possible to arrange them in a substantially vertical direction and arrange them vertically. In this case, the opening 38b of the anti-magnetic plate 38 may be formed so as to face the entire shape of the antenna 32 as in the above-described embodiments, or may be formed so as to face the end of the antenna 32. For example, it may be formed on the rising portion 38a.
[0024]
The material used for the anti-magnetic plate 38 and the non-magnetic members 40 and 42 is not limited to one kind, and a plurality of metals and non-magnetic members can be used in combination.
[0025]
In addition, regarding the selection of the material used for the non-magnetic members 40 and 42, the non-magnetic member formed of the material to be used and the experimental antenna are installed in the experimental case, and the transmitting antenna installed at a predetermined position is set. An experiment for transmitting a signal was carried out to select. As a result of this experiment, in the case of gold, silver, copper, brass, aluminum, magnesium, zinc, and their alloys, the gain was 2-3 dB (decibel) compared to the case of titanium, titanium alloy, stainless steel, and tantalum carbide. Got higher.
[0026]
In addition, comparing the electrical resistivity of the metals used in the experiment, it was found that those having an electrical resistivity of 7 μΩ-cm or less can maintain good reception sensitivity. As a result, if the nonmagnetic members 40 and 42 are formed of a material such as gold, silver, copper, brass, aluminum, magnesium, zinc, or an alloy thereof, the reception sensitivity can be obtained even when the anti-magnetic plate 38 is used. Has been found to be good.
[0027]
【The invention's effect】
According to the present invention, the timepiece can be protected from external magnetism by providing the anti-magnetic plate even in the case of a radio timepiece, so that the time display accuracy can be improved.
[0028]
In addition, even if a magnetic-resistant plate is provided, the aperture and the non-magnetic member are provided in the magnetic-resistant plate, so that the deterioration of the radio wave receiving performance of time information and the like can be remarkably reduced, and the original performance of the radio clock is affected. A magnetically resistant structure can be realized without using a magnetic field.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a radio-controlled timepiece according to a first embodiment of the present invention.
FIG. 2 is a plan view of the anti-magnetic plate shown in FIG.
FIG. 3 is a sectional view showing a radio-controlled timepiece according to a second embodiment of the present invention.
FIG. 4 is a sectional view showing a radio-controlled timepiece according to a third embodiment of the present invention.
FIG. 5 is a sectional view showing a radio-controlled timepiece according to a fourth embodiment of the present invention.
FIG. 6 is a sectional view showing a radio-controlled timepiece according to a fifth embodiment of the present invention.
FIG. 7 is a plan view of the anti-magnetic plate shown in FIG. 6 as viewed from the back cover direction.
FIG. 8 is a sectional view showing a conventional example of the structure of a general wristwatch using a magnetic-resistant plate.
[Explanation of symbols]
2 Case 4 Movement 6 Middle frame 8 Back cover 8a Core 10 Magnetic-resistant plate 12 Watch case 14 Body 14a Step 14b Inwardly protruding portion 14c Inner side surface 16 Back cover 16a Rising portion 18 Glass 20,22 Packing 24 Movement 26 Dial 26 Pointer 30 Resin middle frame 32 Antenna 34 Magnetic core material 36 Coil 38 Magnetic-resistant plate 38a Rising part 38b Opening 38c Notch 40, 42 Nonmagnetic member 40b Opening 44 Side pipe

Claims (12)

A radio-controlled timepiece in which an antenna, a timepiece device, and an anti-magnetic plate are housed in a watch case, and the anti-magnetic plate disposed in the watch case has an opening in a portion facing the antenna. The antenna includes a magnetic core material and a coil wound around the magnetic core material, and the anti-magnetic plate to which the antenna is projected in parallel along at least one plane including an axis of the magnetic core material. 2. The radio-controlled timepiece according to claim 1, wherein an opening is provided in the radio timepiece. The antenna is constituted by a magnetic core material and a plurality of coils wound around the magnetic core material, and an opening is provided in at least the magnetic-resistant plate facing each end of the antenna. Item 7. The radio controlled timepiece according to Item 1. The radio-controlled timepiece according to claim 1, wherein the antenna is disposed outside the magnetic-resistant plate. The radio-controlled timepiece according to claim 1, wherein at least a part of the antenna protrudes from an opening of the anti-magnetic plate and is located on the inner side of the body of the watch case. 2. The radio-controlled timepiece according to claim 1, wherein at least a part of the antenna protrudes from an opening of the magnetic-resistant plate and is located on a back cover side of the watch case. 2. The radio-controlled timepiece according to claim 1, wherein at least a part of the antenna protrudes from an opening of the anti-magnetic plate and is located on a display panel side. The radio timepiece according to any one of claims 1 to 7, wherein the anti-magnetic plate is made of pure iron or permalloy. 9. The radio-controlled timepiece according to claim 1, wherein a non-magnetic member having an electric resistivity of 7.0 [mu] [Omega] -Cm or less is provided on an inner surface of the magnetic-resistant plate. The radio timepiece according to claim 1, wherein the nonmagnetic member is provided in an opening of the magnetic-resistant plate. The radio timepiece according to claim 9, wherein the nonmagnetic member is made of at least one of copper, aluminum, magnesium, zinc, silver, gold, and an alloy thereof. The non-magnetic member has a rising portion rising in the direction of the display panel, and the rising portion contacts a part of the timepiece case to regulate the rotation of the magnetic-resistant plate. Item 12. The radio controlled clock according to any one of Items 1 to 11.

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