JP3515209B2 - Bar antenna structure of radio clock - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a bar antenna of a radio-controlled timepiece.

[0002]

2. Description of the Related Art The structure of a radio timepiece having a conventional bar antenna is shown in FIGS. In the structure shown in FIG. 7, the bar-shaped bar antenna 101 is arranged in the space formed between the lower surface of the glass 103 and the upper surface of the dial 104 in the watch case 102. Bar antenna 101
Is located at the center of the space portion in the 12 o'clock to 3 o'clock direction, and is supported by the support portion 101a formed at one end thereof.
It is fixed at 2. In the structure shown in FIG. 8, the storage case 1 made of plastic or a non-magnetic material is disposed near the side surface of the watch case 102 in the 9 o'clock direction.
05, the bar antenna 101 is arranged. The bar antenna 101 has a support portion 101a formed at one end thereof.
Thus, it is fixed and enclosed inside the storage case 105. Further, 103 is a glass placed on the upper surface of the watch case 102, and 104 is a dial located below the glass 103. The bar antenna 101 shown in FIGS. 7 and 8
Is a coil wound around the outer circumference of one long rod-shaped ferrite body. Whichever structure shown in FIG. 7 or FIG. 8 is used, the bar antenna 101 is required to be mounted on the watch case 102 of the wristwatch.
It is easy to see that it needs to be thin, small in diameter, short and small.

[0003]

However, the ferrite body of the bar antenna can be formed into various shapes because it is formed by baking and hardening metal powder, but it has a drawback of being extremely brittle. In particular, if the ferrite body is thin, has a small diameter, is short, and is small, it is easily cracked by an external force such as an impact load or pressing. When the ferrite body is broken, the inductance of the coil is reduced, and the bar antenna cannot receive the target frequency. Therefore, if the radio-controlled watch is a wristwatch,
Since the ferrite body as well as the bar antenna is thin and have a small diameter, when an external force such as an impact load or a pressure is applied to the watch case, the ferrite body is easily cracked and it becomes impossible to receive the target frequency. For example, it is common for the wearer to drop the wrist watch by mistake,
Due to this drop, the ferrite body of the radio-controlled watch is easily broken or broken. Therefore, even if the radio clock is dropped even once, there may be a problem in reception. Further, if an attempt is made to buffer the external force such as impact load or pressing force on the watch case to avoid cracking of the ferrite body, not only the structure of the bar antenna support portion 101a and the storage case 105 becomes complicated, but also the watch case itself. In order to buffer the external force, the structure of had to be seismic and shock resistant.
For this reason, there has been a problem that the man-hours for manufacturing the watch case and the load of quality assurance increase, which causes a manufacturing cost to increase.

An object of the present invention is to solve the above problems, and a first object thereof is to provide a structure of a bar antenna in which a ferrite body is not cracked or broken by an external force such as impact load or pressure. However, it is intended to improve the reliability of the radio clock.

A second object of the present invention is to make the watch case quake-proof and shock-proof by making the structure itself quake-proof and shock-proof, thereby ensuring manufacturing man-hours and quality assurance. It is an object of the present invention to provide a bar antenna structure capable of avoiding an increase in the load and reducing the manufacturing cost of a radio-controlled timepiece.

[0006]

The constitution of the present invention is as follows. To achieve the above object, in a radio-controlled timepiece having a bar antenna for receiving radio waves, the bar antenna includes a plurality of ferrite bodies, a hollow frame body made of synthetic resin, and the outside of the frame body. It is composed of a coil wound around the circumference, and the ferrite bodies are connected and held in a line inside the frame body with a gap provided therebetween.

The frame body is characterized in that it has an outwardly projecting folded portion at a portion matching the gap between the ferrite bodies.

The coil wound around the frame body is characterized in that it has a bending portion outwardly curved at a portion that coincides with the bending portion.

Alternatively, in a radio-controlled timepiece provided with a bar antenna for receiving radio waves, the bar antenna has a plurality of ferrite bodies, coils wound around the outer periphery of the ferrite body, and a bar-shaped holding member. It is characterized in that it comprises a body, and an elastic body is arranged between the front ferrites to connect and hold the front ferrites in a line on the outer periphery of the rod-shaped holding body.

A through hole is formed in each of the ferrite bodies along the connecting direction, and the rod-shaped holding body is inserted into the through hole.

The elastic body is a ring member made of rubber or plastic and having a through hole.

A concave groove is formed in each of the ferrite bodies along the connecting direction, a convex portion is formed on the outer periphery of the rod-shaped holder, and the concave groove is engaged with the convex portion.

The elastic body is a substantially C-shaped ring member made of rubber or plastic and having a notch having the same shape as that of the concave groove. The notch of the C-shaped ring member is provided with a convex portion of the rod-shaped holder. It is characterized in that it is arranged to be engaged with.

The elastic body is an elastic adhesive for fixing the ferrite bodies to each other and to the rod-shaped holding body.

The coil to be wound is characterized in that it has a bending portion curved outwardly in a portion corresponding to the elastic body.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described in detail below with reference to the drawings. 1 is a sectional view of a main part of a bar antenna showing a first embodiment of the present invention according to claims 1 and 2 of the present invention.
Is an example of a cross section of the main part of the ferrite body shown in FIG.
Is another example of the cross section of the main part of the ferrite body shown in FIG. 1, and will be described below according to this.

A feature of the first embodiment of the present invention is that the bar antenna has a bendable structure in order to prevent breakage accidents due to external factors such as impact and pressing. In the figure, 1 is a bar antenna for receiving radio waves from a radio-controlled timepiece, and 2 is a ferrite body. The ferrite body of the conventional bar antenna was one long rod-shaped one, but each of the ferrite bodies 2 of the present invention was obtained by cutting the conventional rod-shaped ferrite body at several locations along the radial direction. It is like a short rod. The plurality of ferrite bodies 2 are connected and held in a row in a hollow cylindrical frame body 6 made of an elastically deformable synthetic resin, with a predetermined gap provided therebetween. The predetermined gap is provided between each of the ferrite bodies 2 so that the bar antenna 1 can be bent at the gap. Then, the coil 3 is wound around the outer periphery of the frame body 6, so that the bar antenna 1
Is completed. The end of the coil 3 is connected to the receiving device 7, as shown in FIG. The receiving device 7
It is placed inside the module of a radio-controlled watch (not shown).

The bar antenna 1 thus configured
Can be bent in the gaps between the ferrite bodies 2 while elastically deforming the frame body 6, so that the bar antenna 1 bent in the individual gaps is elastically gently curved as a whole. Therefore, even if an external force such as a shock or a pressure is applied, the bar antenna 1 elastically bends and absorbs the load of the external force, so that the ferrite body 2 is not cracked or damaged. Further, since the bar antenna 1 can be bent even when the bar antenna 1 is incorporated in a wristwatch, not only the assembling property is improved, but also the bending of the ferrite body at the time of assembling can be eliminated.

By the way, as means for connecting and holding the ferrite body 2 in the frame body 6, firstly, the frame body 6 is used.
Is molded from elastic rubber synthetic resin so that the inner diameter of the frame body 6 is smaller than the outer diameter of the ferrite body 2. Then, while the frame body 6 is elastically deformed outward, the ferrite body 2 is inserted into the frame body 6 and press-fitted and fixed. The press-fitting margin is set within the elastic deformation region of the frame body 6. Secondly, there is a method of molding the frame 6 as a heat-shrinkable thin film pipe-shaped resin. When the ferrite body 2 is inserted into the frame body 6 and then heated with hot air or hot water, the frame body 6 contracts, so that the ferrite body 2 is fixed in the frame body 6. Alternatively, the frame body 6 and the ferrite body 2 may be adhesively fixed with an adhesive, or the above-mentioned first and second means for connecting and holding may be combined with adhesive fixation to further increase the fixing force. Is also good. In any case, it is preferable that the frame 6 is made of an elastically deformable synthetic resin so that the bar antenna 1 can be bent. The cross-sectional shape of the ferrite body 2 can be freely selected depending on the mounting situation, but as the most common representative example of a radio-controlled timepiece as a wristwatch, a cylindrical shape in FIG. 2 and a rectangular cross-sectional shape in FIG. 3 are shown.

Further, the ferrite body 2 is attached to the frame body 6.
A bent portion 6a protruding outward may be provided at a portion matching the gap between the respective portions. Then, the bar antenna 1
However, since the bent portions 6a elastically bend when bent in the gaps between the ferrite bodies 2, the frame bodies can be bent together more easily. When the winding is loosened, the coil 3 tries to spread in the axial direction of the bar antenna 1. However, when the bent portion 6a is provided, the bent portion 6a prevents the coil 3 from spreading due to the looseness. Therefore, it is possible to prevent the winding of the coil 3 from being loosened. In addition, since the coil 3 does not loosen when it is wound, the coil 3 can be easily wound. Therefore, as in the conventional case, a varnish, a coating agent, or the like is applied and fixed to the wound coil 3,
It is no longer necessary to prevent roll collapse.

Furthermore, the coil 3 wound around the frame body 6 may be provided with a bending portion 3a curved outwardly at a portion corresponding to the bent portion 6a. Then, when the bar antenna 1 is bent due to an impact or a pressure, the bending portion 3a expands and contracts to prevent the coil 3 from breaking. Further, the same effect can be obtained by winding the coil 3 around the bent portion 6a and not treating it with a varnish or a coating agent.

Next, the second embodiment of the present invention will be described in detail. FIG. 4 is a sectional view of a main part of a bar antenna showing a second embodiment of the present invention, which will be described below.

The bar antenna 1 comprises a plurality of ferrite bodies 2, a coil 3 wound around the outer periphery of the ferrite body 2, and a rod-shaped holding body 4, and an elastic body 5 is provided between the ferrite bodies 2. The rod-shaped holding bodies 4 are arranged and connected and held in a line on the outer periphery of the rod-shaped holding body 4. The end of the coil 3 is connected to the receiving device 7, as shown in FIG. As the rod-shaped holder 4, a rod-shaped magnetic body or an elastically deformable rod-shaped elastic body can be selected.
For the rod-shaped holding body 4 as a rod-shaped magnetic body, a material having good magnetic permeability, high impact and bending strength, and good plastic workability is suitable. For example, pure iron or iron-based alloy having high magnetic permeability can be used. For the rod-shaped holding body 4 as the rod-shaped elastic body, it is preferable to use an elastically deformable synthetic resin.

When the rod-shaped holder 4 as a rod-shaped magnetic body is used, the bar antenna 1 thus constructed is used.
Prevents the hard deformation of the ferrite body 2 from breaking, because the hard rod-shaped holder 4 is not deformed by the external force even when an external force such as an impact or a pressing force in the direction of breaking the ferrite body 2 is applied. You can Further, unlike the conventional single rod-shaped ferrite body, the ferrite body 2
Is originally divided into a plurality of parts, so that the external force applied to each of the ferrite bodies 2 is dispersed. Therefore, each of the ferrite bodies 2 can withstand a larger external force than in the conventional case. In addition, the elastic body 5 disposed between the ferrites 2 prevents the ferrites 2 from coming into contact with each other, and absorbs and buffers external force such as impact or pressing by its elastic deformation. Each of the ferrites 2 and the rod-shaped holder 4
It is effective to dispose an elastic body also between the outer circumference and the outer circumference, because the external force can be further buffered.

When the rod-shaped holding body 4 is used as the rod-shaped elastic body, the bar antenna 1 elastically deforms the rod-shaped holding body 4 as in the first embodiment, and each of the ferrite bodies 2 is deformed. The elastic body 5 in between can bend and bend.

In order to connect and hold the ferrite bodies 2 in a line on the outer circumference of the rod-shaped holding body 4, the ferrite bodies 2
It is advisable to form a bead shape by forming a through hole along the connecting direction in each of the above and insert the rod-shaped holding body 4 into the through hole. Then, the ferrite bodies 2 can be connected to the outer periphery of the rod-shaped holding body 4 in a line with good workability. To fix the ferrite body 2 and the rod-shaped holding body 4,
An adhesive is applied and fixed to the through hole of the ferrite body 2 and the outer diameter portion of the rod-shaped holding body 4. The adhesive is preferably a rubbery elastic adhesive. When an elastic adhesive is used, external force such as impact or pressing is absorbed and buffered by its elastic deformation, so that the ferrite body 2 can be further prevented from cracking or breaking.

The elastic body 5 is preferably a ring member made of rubber or plastic and having a through hole.
As the elastic body 5, rubber, plastic having high elasticity, or resin foam sheet is suitable. When the bar antenna 1 is deformed by impact or pressure, the elastic body 5 between the ferrite bodies 2 absorbs the deformation and prevents the bar antenna 1 from being broken.

Alternatively, the elastic body 5 may be an elastic adhesive. Then, an elastic adhesive as the elastic body 5 can be used to buffer the external force such as impact or pressing, and at the same time, the ferrite bodies 2 are fixed to each other, and at the same time, the ferrite body 2 and the rod-shaped holding body 4 are fixed. Can be fixed. Therefore, the workability is improved and the number of parts is reduced, so that the cost can be reduced. Further, if an elastic adhesive as the elastic body 5 is applied and fixed to the through hole of the ferrite body 2 and the outer diameter portion of the rod-shaped holding body 4, the ferrite body 2 and the rod-shaped holding body 4 are connected. The fixing force can be increased, and the applied external force can be buffered.

Further, in the coil 3 to be wound, similarly to the first embodiment, it is preferable to form an outwardly curved flexible portion 3a at a portion that matches the elastic body 5. Then, when the bar antenna 1 is bent due to an impact or a pressure, the bending portion 3a expands and contracts to prevent the coil 3 from breaking.

Next, the third embodiment of the present invention will be described in detail. FIG. 5 is a cross-sectional view of a main part of a bar antenna showing a third embodiment of the present invention, and FIG. 6 is an exploded perspective view showing the configurations of the ferrite body and the rod-shaped holding body shown in FIG. The following is a description of this. The third embodiment is a modification of the second embodiment. The third embodiment is different from the second embodiment in the means for connecting and holding the ferrite body to the rod-shaped holding body in a line.

A concave groove 2a is formed in each of the ferrite bodies 2 along the connecting direction, a convex portion 4a is formed on the outer periphery of the rod-shaped holder 4, and the concave groove 2a is engaged with the convex portion 4a. Then, the ferrite body 2 is fixed to a part of the outer circumference of the rod-shaped holding body 4. The coil 3 is wound around the outer periphery of the ferrite body 2 including the outer periphery of the rod-shaped holding body 4. As the rod-shaped holder 4, a rod-shaped magnetic body or an elastically deformable rod-shaped elastic body can be selected as in the second embodiment. When a rod-shaped magnetic body is selected as the rod-shaped holding body 4, in order to form the convex portion 4a, for example, rolling by a forming roll, cold drawing, or metal injection capable of processing a complicated shape is used. can do.

The elastic body 5 is a substantially C-shaped ring member made of rubber or plastic and having a notch having the same shape as the concave groove 2a. The notch of the C-shaped ring member is used as the rod-shaped holding member 4. When the bar antenna 1 is deformed due to impact or pressure, the elastic body 5 between the ferrite bodies 2 absorbs the deformation and prevents the bar antenna 1 from being broken.

The elastic body 5 may be an elastic adhesive for fixing each of the ferrite bodies 2 to each other and to the rod-shaped magnetic body 4 as in the second embodiment.

Further, the wound coil 3 whose end is connected to the receiving device 7 has the same structure as in the second embodiment.
If the outwardly curved flexure 3a is formed in a portion that matches the elastic body 5, the flexure is generated when the elastic body 5 is elastically deformed by an external force such as impact or pressure being applied to the bar antenna 1. Since the portion expands and contracts, it is possible to prevent the coil 3 from breaking.

[0035]

As described above, according to the present invention, in a radio-controlled timepiece having a bar antenna for receiving radio waves, the bar antenna includes a plurality of ferrite bodies.
A configuration in which a hollow frame body made of synthetic resin and a coil wound around the outer circumference of the frame body are provided, and the ferrite bodies are connected and held in a line inside the frame body with a gap provided therebetween. Therefore, since the bar antenna can be bent in the gap between the ferrite bodies while elastically deforming the frame body, the bar antenna bent in each gap is elastically elastic as a whole. Can be gently curved. Therefore, even if an external force such as a shock or a pressure is applied, the bar antenna elastically bends and absorbs the load of the external force, so that the ferrite body is not cracked or damaged. Further, since the bar antenna can be bent even when the bar antenna is incorporated into a wristwatch, not only the assembling property is improved but also the bending of the ferrite body at the time of assembling can be eliminated.

Further, since the frame body has a folded portion projecting outward in a portion that coincides with the gap between the ferrite bodies, the bar antenna is provided in the gap between the ferrite bodies. When bent, the bent portion elastically bends, so that the frame body can be bent together more easily. When the coil is loosely wound, the coil tries to spread in the axial direction (longitudinal direction) of the bar antenna. However, when the bent portion is provided, the bent portion prevents the spread due to the looseness of the coil. It is possible to prevent the coil from being loosened. In addition, since the winding does not loosen when the coil is wound, the coil can be easily wound.

Since the coil wound around the frame body has the bending portion which is curved outward in the portion that coincides with the bending portion, when the bar antenna bends due to impact or pressure, The flexible portion can be expanded and contracted to prevent disconnection of the coil.

Alternatively, the bar antenna includes a plurality of ferrite bodies, a coil wound around the outer periphery of the ferrite body, and a rod-shaped holding body, and an elastic body is arranged between the front ferrites, If the rod-shaped holding body is configured to be connected and held in a line on the outer circumference, when a rod-shaped magnetic body is used as the rod-shaped holding body, the bar antenna has an impact or a pressing force in the direction of breaking the ferrite body. Even if an external force is applied, the hard rod-shaped holder is not deformed by the external force, so that the ferrite body can be prevented from being deformed. Further, unlike the conventional single rod-shaped ferrite body, since the ferrite body is originally divided into a plurality of pieces, the external force applied to each of the ferrite bodies is dispersed. Therefore, each of the ferrite bodies can endure a larger external force than in the conventional case. When a rod-shaped elastic body is used as the rod-shaped holding body, the bar antenna can be bent and curved by the elastic body between the ferrite bodies while elastically deforming the bar-shaped holding body. Therefore, even if an external force such as impact or pressure is applied,
Since the bar antenna is elastically curved and absorbs the load of the external force, the ferrite body is not cracked or damaged. In addition, the elastic body arranged between the ferrites prevents the ferrites from coming into contact with each other, and absorbs an external force such as a shock or a pressure by its elastic deformation to buffer the external force. It is effective to dispose an elastic body between each of the ferrites and the outer circumference of the rod-shaped holding body, because the external force can be further buffered.

In order to connect and hold the ferrite bodies in a line on the outer periphery of the rod-shaped holding bodies, through holes are formed in each of the ferrite bodies along the connecting direction, and the rod-shaped holding bodies are inserted into the through holes. good. Then, the ferrite bodies can be connected to the outer periphery of the rod-shaped holding body in a line with good workability.

The elastic body may be a ring member made of rubber or plastic and having a through hole. Then, at the same time when the rod-shaped holding body is inserted into the ferrite body, the rod-shaped holding body can be inserted into the through hole of the elastic body so as to be located between the ferrite bodies, and the workability is good. .

Further, it is also possible to form a concave groove in each of the ferrite bodies along the connecting direction, form a convex portion on the outer periphery of the rod-shaped holding body, and engage the concave groove with the convex portion. With good performance, the ferrite bodies can be connected and held in a line on the outer periphery of the rod-shaped holding body.

In this case, the elastic body is made of rubber or plastic and is a substantially C-shaped ring member having a notch having the same shape as the recessed groove, and the notch of the C-shaped ring member is made of the rod-shaped holding member. If it is configured to engage with the convex portion, at the same time when the rod-shaped holding body is engaged with the ferrite body, the rod-shaped holding body is provided in the through hole of the elastic body so as to be located between the ferrite bodies. It can be engaged and workability is good.

The elastic body may be configured as an elastic adhesive agent without being a ring member having a through hole or a substantially C-shaped ring member. Then, the ferrite bodies can be fixed to each other, and at the same time, the ferrite bodies can be fixed to the rod-shaped holding body, and the fixation of the ferrite bodies to the rod-shaped holding body can be made more reliable. it can.

Further, in this case, if the coil to be wound has a bending portion curved outwardly in a portion matching the elastic body, an external force such as impact or pressing is applied to the bar antenna. When the elastic body is elastically deformed under load, the flexible portion expands and contracts, so that disconnection of the coil can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a bar antenna showing a first embodiment of the present invention.

FIG. 2 is an example of a cross-section of a main part of the ferrite body shown in FIG.

FIG. 3 is another example of a cross section of the main part of the ferrite body shown in FIG.

FIG. 4 is a cross-sectional view of a main part of a bar antenna showing a second embodiment of the present invention.

FIG. 5 is a sectional view of a main part of a bar antenna showing a third embodiment of the present invention.

6 is an exploded perspective view showing configurations of a ferrite body and a rod-shaped magnetic body shown in FIG.

FIG. 7 is a structure of a radio-controlled timepiece provided with a conventional bar antenna.

FIG. 8 shows the structure of a radio-controlled timepiece provided with another conventional bar antenna.

[Explanation of symbols]

1 bar antenna 2 Ferrite body 2a concave groove 3 coils 3a flexure 4 Rod-shaped holder 4a convex part 5 elastic body 6 frame 6a Bent section 7 Receiver 101 bar antenna 101a support part 102 cases 103 glass 104 dial 105 storage case

Claims (10)

(57) [Claims] 1. A radio-controlled timepiece having a bar antenna for receiving radio waves on a timepiece, wherein the bar antenna is wound around a plurality of ferrite bodies, a hollow frame body made of synthetic resin, and the outer periphery of the frame body. A bar antenna structure comprising: a coil to be rotated, wherein the ferrite bodies are connected and held in a line inside the frame body with a gap provided therebetween. 2. The bar antenna structure according to claim 1, wherein the frame body has a bent portion protruding outward in a portion that matches a gap between the ferrite bodies. 3. The bar antenna according to claim 1, wherein the coil wound around the frame body has an outwardly curved flexible portion at a portion that matches the bent portion. Construction. 4. A radio-controlled timepiece having a bar antenna for receiving radio waves in a timepiece, wherein the bar antenna has a plurality of ferrite bodies, coils wound around the outer periphery of the ferrite body, and a bar-shaped holding member. A bar antenna structure comprising a body, wherein elastic bodies are arranged between the front ferrites, and are connected and held in a line on the outer periphery of the rod-shaped holding body. 5. The bar antenna structure according to claim 4, wherein a through hole is formed in each of the ferrite bodies along a connecting direction, and the rod-shaped holding body is inserted into the through hole. 6. The bar antenna structure according to claim 5, wherein the elastic body is a ring member made of rubber or plastic and having a through hole. 7. The ferrite body is formed with a concave groove along a connecting direction, a convex portion is formed on an outer periphery of the rod-shaped holding body, and the concave groove is engaged with the convex portion. The bar antenna structure according to claim 4. 8. The elastic body is a substantially C-shaped ring member made of rubber or plastic and having a notch having the same shape as the recessed groove, and the notch of the C-shaped ring member is formed in the rod-shaped holding member. The bar antenna structure according to claim 6, wherein the bar antenna structure is arranged so as to be engaged with the convex portion. 9. The bar antenna according to claim 4, wherein the elastic body is an elastic adhesive that secures the ferrite bodies to each other and secures to the rod-shaped holding body. Construction. 10. The bar antenna structure according to claim 4, wherein the coil that is wound has a bending portion that curves outward in a portion that matches the elastic body.