JP6040036B2 - Multi-frequency antenna, manufacturing method thereof, and portable terminal - Google Patents

Description

  The present invention relates to a multi-frequency shared antenna that is provided with a resonance circuit in an antenna body and operates in different frequency bands, a manufacturing method thereof, and a portable terminal including the multi-frequency shared antenna.

  2. Description of the Related Art Conventionally, a multi-frequency shared antenna that is provided with a resonance circuit in an antenna body and operates in different frequency bands is known. For example, Patent Document 1 discloses a circuit in which a resonance circuit including a coil and a capacitor is provided in an antenna body so as to resonate in two frequency bands (see page 2 of Patent Document 1 and FIG. 10). reference).

JP-A-9-139618

  By the way, a configuration in which a resonance circuit is provided in the antenna body to operate the antenna in different frequency bands has advantages that the resonance circuit of the communication device body can be eliminated or the structure thereof can be simplified, but normally the resonance circuit of the antenna body. Therefore, it is difficult to use it for a telescopic rod antenna such as a portable terminal which is strongly required to reduce the size, the diameter, and the space for storing the housing. Furthermore, when a resonance circuit is provided in the antenna body of the telescopic rod antenna to make a multi-frequency antenna, the antenna body is flexible and sufficiently stretchable to obtain a good adjustment function to a position with high radio wave sensitivity. It is desirable to ensure.

  Further, when a resonance circuit is provided in the antenna body, the mechanical structure is usually complicated, and another problem that the number of parts increases is caused.

  The present invention has been proposed in view of the above problems, and at the same time, it is possible to provide a resonance circuit in the antenna body of the telescopic rod antenna while meeting the demands for downsizing, diameter reduction, and space saving. An object of the present invention is to provide a multi-frequency shared antenna capable of ensuring the flexibility and sufficient stretchability of the antenna body of the telescopic rod antenna, a manufacturing method thereof, and a portable terminal equipped with the multi-frequency shared antenna. Another object of the present invention is to provide a multi-frequency shared antenna that can be configured with a simple mechanical structure while minimizing the increase in the number of components, a method for manufacturing the multi-frequency shared antenna, and a portable terminal equipped with the multi-frequency shared antenna. It is to provide.

The multi-frequency shared antenna of the present invention has a telescopic rod-shaped antenna element portion and a holding portion that holds the antenna element portion so that the antenna element portion can be bent, and the holding portion is electrically connected to the antenna element portion. A substantially cylindrical antenna element conducting portion provided on the power supply portion, a substantially cylindrical power feeding conducting portion provided so as to be conducted to the power feeding portion, and the antenna element conducting portion and the feeding conduction provided substantially internally in the power feeding conducting portion. An insulating cylinder interposed between the first and second portions, and an axial direction of the insulating cylinder inside the insulating cylinder, the upper end portion being connected to the antenna element conducting portion and coupled, and the lower end portion being connected to the power supply conducting portion. And a coil that is conductively coupled to the portion.
According to this configuration, the resonance circuit can be configured with a simple mechanical structure that does not take up space, such as the antenna element conducting portion, the power feeding conducting portion, the insulating cylinder, and the coil of the holding portion, and can be reduced in size, diameter, and storage space The resonance circuit can be provided in the antenna body of the telescopic rod antenna while meeting the demand for space saving and the like, and the resonance circuit of the communication device body can be eliminated or the structure thereof can be simplified. At the same time, the antenna element portion can be flexibly held by the holding portion, and the stretchability can be secured over the entire length of the antenna element portion to be held. Stretchability can be ensured, and a good adjustment function to a position with high radio wave sensitivity can be obtained. In addition, the antenna can be a multi-frequency antenna that is difficult to bend with a simple mechanical structure, and can be configured with a small number of components, so that an increase in the number of components can be minimized. Further, it is possible to flexibly adapt to the increase or decrease of the resonance frequency by increasing or decreasing the number of turns of the coil.

The multi-frequency shared antenna of the present invention is composed of a lower pipe that is externally mounted on the insulating cylinder, and a lower end coupling portion that is fixed so as to close a bottom side of the lower pipe. The lower end portion of the coil is coupled to the lower end coupling portion at a position away from the central axis of the lower pipe.
According to this structure, the lower end part of a coil can be couple | bonded with a lower end coupling | bond part, and the lower end part of a coil can be couple | bonded easily with an electric conduction part. Also, with the configuration in which the lower end of the coil is coupled at a position away from the central axis, the lower end coupling unit to which the coil is coupled is rotated to finely adjust the coil diameter and the number of turns to ensure a good resonance state. It becomes possible to fix the lower end coupling portion to the lower pipe. Therefore, it is possible to reliably obtain an antenna having a good resonance state with respect to a plurality of frequencies, and eliminate or suppress the production of an antenna having an inferior resonance state as much as possible, thereby dramatically improving the manufacturing yield. Is possible.

The multi-frequency antenna according to the present invention is characterized in that the lower end coupling portion includes a small diameter portion engaged with the lower pipe and a large diameter portion contacting the lower end of the lower pipe.
According to this configuration, the lower end coupling portion can be stably fixed to the lower pipe. Also, it is possible to finely adjust the coil diameter and the number of turns by rotating the large diameter portion with the small diameter portion engaged in the lower pipe and rotating the lower end coupling portion to which the coil is coupled. It becomes possible to adjust the state easily and stably.

The multi-frequency antenna according to the present invention includes a stationary mechanism in which the antenna element conducting portion holds the antenna element portion so that the antenna element portion can be bent at an upper end portion, and biases the antenna element portion to place it at a required position. It is comprised from an upper side pipe and the upper end coupling part provided so that the bottom side of the said upper pipe may be obstruct | occluded, The upper end part of the said coil is couple | bonded with the said upper end coupling part, It is characterized by the above-mentioned.
According to this configuration, it is possible to more stably place the antenna element portion that is held bendable at a required position by the placement mechanism, and it is possible to provide both the placement mechanism and the resonance circuit in the holding portion. Moreover, the upper end part of a coil can be couple | bonded with an upper end coupling part, and the upper end part of a coil can be couple | bonded easily with an antenna element conduction | electrical_connection part.

In the multi-frequency antenna according to the present invention, the upper end coupling portion includes a first small diameter portion engaged in the upper pipe, a second small diameter portion engaged in the insulating cylinder, and the first small diameter portion. And an intermediate flange portion that contacts the lower end of the upper pipe and is located between the second small diameter portion and an upper end flange portion that contacts the upper end of the power supply conducting portion. The upper end flange portion of the insulating cylinder and the intermediate flange portion of the upper end coupling portion are provided in contact with each other.
According to this configuration, the upper end coupling portion can be stably engaged with the upper pipe and the insulating cylinder, and the upper end coupling portion can be stably placed at a position necessary for the configuration of the resonance circuit by the intermediate flange. Can be stationary. Further, the insulating cylinder can be stably placed at a required position by contacting the upper end flange of the insulating cylinder and the intermediate flange of the upper end coupling part.

In the multi-frequency shared antenna of the present invention, the inner peripheral surface of the insulating cylinder and the coil are provided apart from each other.
According to this configuration, a capacitor can be formed using both of the insulating cylinder and the air layer, and a multi-frequency shared antenna with a higher degree of freedom of adjustment can be obtained.

The multi-frequency antenna according to the present invention is characterized in that the antenna element portion has a small-diameter front-end antenna element in the extended state, or a large-diameter front-end antenna element in the extended state.
According to this configuration, the telescopic rod antenna having a small-diameter or large-diameter antenna element on the distal end side in the extended state can be a multi-frequency common antenna that can achieve the effects of the present invention. The multi-frequency antenna according to the present invention is provided with a resonance circuit in the holding portion, so that both the antenna having a small diameter at the tip side (the base side has a large diameter) and the antenna having a large diameter at the tip side (the base side has a small diameter) are extendable. The rod antenna can be applied while ensuring the same stretchability as when no resonance circuit is provided.

The method for manufacturing a multi-frequency antenna according to the present invention is a method for manufacturing the multi-frequency antenna according to the present invention, wherein the lower end of the coil is located at a position where the lower end of the coil is separated from the central axis of the lower pipe. In a state where the small diameter portion is coupled to the small diameter portion and the small diameter portion is engaged in the lower pipe, the lower end coupling portion is rotated as necessary to resonate with respect to a predetermined resonance frequency according to a test result of a resonance state. A step of adjusting the state is provided.
According to this configuration, if necessary, the resonance state is adjusted within a necessary range by rotating the lower end coupling portion and adjusting the resonance state with respect to a predetermined resonance frequency based on the inspection result of the resonance state of the intermediate product. Can be carried out easily and stably. In addition, it is possible to reliably and efficiently manufacture an antenna having a good resonance state with respect to a plurality of frequencies, and eliminate or suppress the production of an antenna having a poor resonance state as much as possible, thereby dramatically improving the manufacturing yield. can do.

The portable terminal of the present invention includes the multi-frequency shared antenna of the present invention.
According to this configuration, a mobile terminal having the effect of the multi-frequency shared antenna of the present invention can be obtained.

  According to the present invention, the multi-frequency antenna can be provided with a resonance circuit in the antenna body of the telescopic rod antenna while meeting the demands such as downsizing, downsizing, and space saving of the storage space, The flexibility and sufficient elasticity of the antenna body of the telescopic rod antenna can be ensured, and further, it can be configured with a simple mechanical structure with a minimum increase in the number of parts.

The longitudinal cross-sectional view of the shortened state of the multi-frequency common antenna of an embodiment. The longitudinal cross-sectional view of the expansion | extension state of the multi-frequency common antenna of embodiment. The longitudinal cross-sectional view which shows the antenna element part and its vicinity in the multifrequency shared antenna of embodiment. The longitudinal cross-sectional view which shows the holding | maintenance part and its vicinity in the multifrequency shared antenna of embodiment. Explanatory drawing of the resonance circuit in the multi-frequency common antenna of an embodiment. The graph which shows the example of the frequency characteristic (SWR) of the multifrequency shared antenna of embodiment.

[Multi-frequency antenna of embodiment]
The multi-frequency shared antenna 1 of the present embodiment is a telescopic rod antenna used for a mobile terminal or the like that receives both mobile multimedia broadcast (MM broadcast) and mobile phone / mobile terrestrial digital broadcast (one seg), for example. 1 to 4, the antenna body is composed of a rod-shaped antenna element portion 2 that is extendable and retractable and a holding portion 3 that holds the antenna element portion 2 in a bendable manner. It is slidably provided in a substantially cylindrical holder 4 to be attached.

  The antenna element section 2 includes a rod-shaped antenna element 21, a first tubular antenna element 22 into which the rod-shaped antenna element 21 can be inserted and retracted, and a second tube in which the first tubular antenna element 22 is inserted and retracted. It is a multistage telescopic type composed of a cylindrical antenna element 23.

  That is, in the shortened antenna element portion 2, the rod-shaped antenna element 21 is housed in the first tubular antenna element 22, and the first tubular antenna element 22 is housed in the second tubular antenna element 23. It has become so. Further, in the extended antenna element portion 2, most of the rod-shaped antenna element 21 is drawn out from the first tubular antenna element 22 and expanded, and most of the first tubular antenna element 22 is the second tube. The antenna element 23 is pulled out and extended.

  A cap 211 is fitted into the upper end of the rod-shaped antenna element 21, and a substantially spherical enlarged diameter portion 212 is formed at the lower end thereof. On the upper side of the enlarged diameter portion 212, a contact spring 213 bulging outward is provided around the rod-shaped antenna element 21, and the contact spring 213 slides while contacting an inner wall of a first cylindrical antenna element 22 described later. Thus, the rod-shaped antenna element 21 and the first cylindrical antenna element 22 are electrically connected via the contact spring 213.

  An opening 221 having a reduced diameter is formed at the upper end of the first tubular antenna element 22, and a diameter-enlarged portion 222 is formed at the lower end of the trumpet shape. On the upper side of the enlarged diameter portion 222, a contact spring 223 bulging outward is provided around the first cylindrical antenna element 22, and the contact spring 223 contacts an inner wall of a second cylindrical antenna element 23 described later. The first cylindrical antenna element 22 and the second cylindrical antenna element 23 are electrically connected via the contact spring 223.

  When the rod-shaped antenna element 21 is extended from the first cylindrical antenna element 22, the length of the contact spring 213 extending in contact with the vicinity of the reduced peripheral edge of the opening 221 is restricted, and the rod-shaped antenna element When 21 is accommodated in the first cylindrical antenna element 22, the length of the cap 211 that abuts on the upper end of the first cylindrical antenna element 22 and is shortened is regulated.

  An opening 231 formed with a reduced diameter is also formed at the upper end of the second cylindrical antenna element 23, and its lower part is closed by a bottom part 232 to form a bottomed cylindrical shape, and is formed at the lower end of the bottom part 232. A substantially semicircular plate-like portion 233 is formed. The plate-like portion 233 has a hole 234 formed substantially at the center, and irregularities (not shown) are alternately formed in the circumferential direction on the peripheral surface of the plate-like portion 233.

  When the first cylindrical antenna element 22 is extended from the second cylindrical antenna element 23, the length at which the upper end of the contact spring 223 abuts on the vicinity of the reduced peripheral edge of the opening 231 is restricted. When the first cylindrical antenna element 22 is accommodated in the second cylindrical antenna element 23, the length of the diameter-enlarged portion 221 that abuts on the bottom 232 or the depth of entry is restricted. It has become.

  The holding part 3 is provided with a substantially cylindrical antenna element conducting part provided so as to be electrically connected to the antenna element part 2, and a substantially cylindrical power feeding provided so as to be conducted via the power feeding part of the portable terminal housing and the holder 4. The antenna element conducting portion in this embodiment includes a conducting portion, an insulating cylinder 35, and a coil 36. The antenna element conducting portion in the present embodiment includes an upper pipe 31 and an upper end coupling portion 32 provided so as to close the bottom side of the upper pipe 31. In addition, the power supply conduction portion in the present embodiment includes a lower pipe 33 and a lower end coupling portion 34 that is fixed so as to close the bottom side of the lower pipe 33.

  At the upper end of the upper pipe 31, bifurcated plate-like portions 311 and 311 are provided, and the plate-like portions 311 and 311 are disposed on both sides of the plate-like portion 233 of the antenna element portion 2, respectively. A hole 312 is formed at substantially the center of the plate-like parts 311 and 311, and the antenna element part 2 is pivotally supported by the holding part 3 by inserting a pin 313 into the hole 312 and the hole 234 of the plate-like part 233. The antenna element portion 2 is held at the upper end portion of the upper pipe 31 so as to be bendable. The antenna element portion 2 is electrically connected to the holding portion 3 through this shaft support portion.

  Inside the upper pipe 31, there are provided a locking body 314 such as a sphere disposed near the upper part below the plate-like portion 311, and an elastic material 315 such as a coil spring that urges the locking body upward. Yes. The locking body 314 is urged upward by the elastic material 315, and the engaging surface of the locking body 314 such as a spherical surface is removably engaged with the concave and convex recesses of the plate-like portion 233 of the antenna element portion 2. . That is, a stationary mechanism for biasing the antenna element portion 2 and placing it at a required position by engaging / disengaging the locking body 314 and the concave portion is built in the upper pipe 31 and is rotatably supported by the holding portion 3. The antenna element portion 2 can be placed in the required direction in which the locking body 314 engages the recess.

  The upper end coupling portion 32 includes a first small-diameter portion 321 engaged in the upper pipe 31, a second small-diameter portion 322 engaged in an insulating cylinder 35 described later, a first small-diameter portion 321 and a second small-diameter portion. And an intermediate flange 323 provided between the lower pipe 322 and the lower end of the upper pipe 31. An elastic material 315 is provided on the upper surface of the first small diameter portion 321 so as to support the elastic material 315. An upper end portion of a coil 36 (to be described later) is fitted into the fitting hole and fixedly coupled to the second small diameter portion 322 by soldering or caulking or the like. In this embodiment, the second small diameter portion 322 is separated from the central axis of the lower pipe 33. The upper end portion of the coil 36 is coupled to the second small diameter portion 322 at this position.

  The lower pipe 33 is a cylindrical pipe that is open at the top and bottom, and is covered with an insulating cylinder 35 described later. The lower end coupling portion 34 includes a small diameter portion 341 engaged with the lower pipe 33 and a large diameter portion 342 that contacts the lower end of the lower pipe 33, and the large diameter portion 342 and the lower end of the lower pipe 33 are connected to each other. It is fixed at the contact point. A lower end portion of a coil 36 (to be described later) is fitted into the small diameter portion 341 and is fixedly coupled by soldering or caulking, and the small diameter portion 341 is located away from the central axis of the lower pipe 33. The lower end of the coil 36 is coupled to the coil.

  The insulating cylinder 35 is substantially housed in the lower pipe 33 that is a power supply conduction portion. At the upper end of the insulating cylinder 35, there is provided an upper end flange 351 that comes into contact with the upper end of the lower pipe 33, which is a power supply conduction section, and the upper end flange 351 of the insulation cylinder 35 and the upper end coupling portion 32 of the antenna element conduction section. The intermediate collar portion 323 is provided in contact therewith. That is, between the upper end coupling part 32 of the antenna element conduction part constituted by the upper pipe 31 and the upper end coupling part 32 and the lower pipe 33 of the feeding conduction part constituted by the lower pipe 33 and the lower end coupling part 34. It is provided intervening.

  Inside the insulating cylinder 35, a coil 36 is arranged so as to align the axial direction with the insulating cylinder 35, and the upper end portion of the coil 36 is conductively coupled to the second small diameter portion 322 of the antenna element conductive portion, The lower end portion is electrically connected to and coupled to the small diameter portion 341 of the power supply conduction portion. The coil 36 may be configured to be provided so as to be in contact with the inner peripheral surface of the insulating cylinder 35, but in the present embodiment, the coil 36 is configured to be provided apart from the inner peripheral surface of the insulating cylinder 35. By using both the insulating cylinder 35 and the air layer, a capacitor is formed, and the multi-frequency antenna 1 having a higher degree of freedom of adjustment can be obtained.

  When the multi-frequency antenna 1 is extended, the lower pipe 33, which is a power supply conduction portion of the holding unit 3, is electrically connected by contacting a contact spring (not shown) of the holder 4 during extension. At the time of shortening, the second cylindrical antenna element 23 of the antenna element portion 2 comes into contact with the contact spring of the holder 4 to be electrically connected to supply power. .

  In the multi-frequency antenna 1 of this embodiment, as shown in FIG. 5, a capacitor 51 is formed in the path of the conductive upper end coupling portion 32, the insulating cylinder 35, and the conductive lower pipe 33. A plurality of pseudo capacitors 52 are formed in the path of the conductive upper end coupling portion 32 -coil 36 -air layer -insulating cylinder 35 -conductive lower pipe 33, and between the antenna element portion 2 and the power feeding portion 6. A circuit equivalent to a state where a plurality of capacitors 52 are connected to the coil 36 at intervals is formed.

  In other words, the multi-frequency antenna 1 can be configured by resonance of different frequencies including the antenna element portion 2, the coil 36, and the capacitor 52. And it can be set as the multi-frequency common antenna 1 which operate | moves by two or more different frequency bands by setting so that two or more some resonance frequency may become a predetermined frequency.

  FIG. 6 shows an example of frequency characteristics of the multi-frequency shared antenna 1. In FIG. 6, the horizontal axis represents frequency, and the vertical axis represents SWR (standing wave ratio). In the illustrated example, the SWR is minimum at around 214 MHz and around 592 MHz, and it can be seen that the multi-frequency shared antenna 1 has excellent resonance with respect to two different frequency bands.

  Further, when the multi-frequency antenna 1 of the present embodiment is manufactured, the lower end portion of the coil 36 is coupled to the small diameter portion 341 of the lower end coupling portion 34 at a position away from the central axis of the lower pipe 33, and the small diameter. In the state where the portion 341 is engaged in the lower pipe 33, an adjustment process is used to adjust the resonance state with respect to a predetermined resonance frequency by rotating the lower end coupling portion 34 as necessary according to the inspection result of the resonance state. If the lower end coupling portion 34 is fixed at the contact portion of the lower pipe 33 after the adjustment, the resonance state can be easily and stably adjusted within a necessary range.

  That is, by rotating the lower end coupling portion 34 and changing the number of turns and the coil diameter according to the inspection result, the inductance of the coil 36 and the conductive upper end coupling portion 32 -coil 36 -air layer -insulation The capacitance of the capacitor 52 through the path of the cylinder 35-conductive lower pipe 33 can be changed and adjusted to a desired resonance state. More preferably, when the adjustment step described above is performed in a state where the upper end portion of the coil 36 is coupled to the upper end coupling portion 32 at a position approximately equidistant from the coupling position of the lower end portion from the central axis of the lower pipe 33, More uniform adjustment of the coil 36, such as a more uniform change in the coil diameter across the top and bottom, can be performed, and it becomes possible to perform easier and more stable adjustment. By performing these frequency adjustment steps, for example, the conventional yield of about 80% can be improved to nearly 100%.

  According to the multi-frequency shared antenna 1 of the present embodiment, the resonance circuit can be configured with a simple mechanical structure that does not take up space, such as the antenna element conduction part, the power feeding conduction part, the insulating cylinder 35, and the coil 36 of the holding part 3. It is possible to provide a resonance circuit in the antenna body of the telescopic rod antenna while meeting the demand for downsizing, diameter reduction, space saving, etc. It can be simplified.

  At the same time, it is possible to hold the antenna element portion 2 in a bendable manner by the holding portion 3 and to ensure stretchability over the entire length of the antenna element portion 2 being held, so that the flexibility of the antenna body of the telescopic rod antenna can be secured. Sufficient elasticity can be ensured and a good adjustment function to a position with high radio wave sensitivity can be obtained.

  In addition, the multi-frequency antenna 1 can be easily bent with a simple mechanical structure, and can be configured with a small number of parts, and an increase in the number of parts can be minimized. Further, it is possible to flexibly adapt to the increase or decrease of the resonance frequency by increasing or decreasing the number of turns of the coil 36.

  Further, by coupling the lower end portion of the coil 36 to the lower end coupling portion 34, the lower end portion of the coil can be easily coupled to the power feeding conduction portion. Further, by coupling the lower end portion of the coil 36 at a position away from the central axis, the lower end coupling portion 34 to which the coil 36 is coupled is rotated to finely adjust the diameter and the number of turns of the coil to ensure a good resonance state. Then, the lower end coupling portion 34 can be fixed to the lower pipe 33. Therefore, it is possible to reliably obtain an antenna having a good resonance state with respect to a plurality of frequencies, and eliminate or suppress the production of an antenna having an inferior resonance state as much as possible, thereby dramatically improving the manufacturing yield. Is possible.

  Further, the lower end coupling portion 34 can be stably fixed to the lower pipe 33 by the small diameter portion 341. Further, the large-diameter portion 342 is rotated with the small-diameter portion 341 engaged in the lower pipe 33, and the diameter and the number of turns of the coil 36 are finely adjusted by the rotation of the lower end coupling portion 34 to which the coil 36 is coupled. Thus, the resonance state can be adjusted easily and stably.

  Further, the antenna mechanism 2 that can be bent can be more stably placed at a required position by the placement mechanism, and both the placement mechanism and the resonance circuit can be provided in the holding portion 3. Further, by coupling the upper end portion of the coil 36 to the upper end coupling portion 32, the upper end portion of the coil 36 can be easily coupled to the antenna element conduction portion.

  In addition, the upper end coupling portion 32 can be stably engaged with the upper pipe 31 and the insulating cylinder 35 by the first small diameter portion 321 and the second small diameter portion 322, and the upper end coupling portion 32 by the intermediate flange portion 323. Can be stably placed at a position required for the configuration of the resonance circuit. Further, by contacting the upper end flange 351 of the insulating cylinder 35 and the intermediate flange 323 of the upper end coupling part 32, the insulating cylinder 35 can be stably placed at a required position.

[Modifications of Embodiment, etc.]
In addition to the configurations of the inventions and embodiments, the invention disclosed in the present specification includes those specified by changing these partial configurations to other configurations disclosed in the present specification within the applicable range, or These components may be specified by adding other components disclosed in this specification, or may be a higher-level concept that is specified by deleting these partial configurations to the extent that partial effects can be obtained. The following modifications are also included.

  For example, the configuration of the substantially cylindrical antenna element conduction portion provided so as to be electrically connected to the antenna element portion 2 and the substantially cylindrical power supply conduction portion provided so as to be electrically connected to the power feeding portion are the same as the upper pipe 31 of the above embodiment. Other than the antenna element conducting portion constituted by the upper end coupling portion 32 and the power feeding conducting portion constituted by the lower pipe 33 and the lower end coupling portion 34, it is appropriate within the scope of the present invention.

  Moreover, although the antenna element part 2 of the said embodiment shall be a thing with the small diameter of the antenna element of the front end side in the expansion | extension state, the antenna element part in which the antenna element of the front end side is large diameter in the expansion | extension state is used. The present invention is also applicable to a multi-frequency shared antenna having, for example, a cylindrical antenna element from the distal end side in an extended state, another cylindrical antenna element that can be stored in the cylindrical antenna element, and another cylindrical antenna element It is good also as a rod-shaped antenna element part etc. which can be expanded and contracted and become a rod-shaped antenna element which can be stored inside. In the present invention, since the holding part 3 is provided with a resonance circuit, the telescopic rod antenna of both the antenna having a small diameter at the tip side (the base side has a large diameter) and the antenna having a large diameter at the tip side (the base side has a small diameter) are resonant. It is possible to ensure the same stretchability as when no circuit is provided.

  The present invention is also applicable to a multi-frequency shared antenna that does not have the above-described stationary mechanism. The multi-frequency antenna of the present invention is preferably applied to a mobile terminal, but can also be applied to other communication devices.

  The present invention receives, for example, both mobile multimedia broadcasting (MM broadcasting) using a frequency band of 207.5 MHz to 222 MHz and terrestrial digital broadcasting (one seg) for mobile phones / mobiles using a frequency band of 470 MHz to 770 MHz. It can be used as a multi-frequency antenna for portable terminals.

DESCRIPTION OF SYMBOLS 1 ... Multi-frequency common use antenna 2 ... Antenna element part 21 ... Rod-shaped antenna element 211 ... Cap 212 ... Diameter expansion part 213 ... Contact spring 22 ... 1st cylindrical antenna element 221 ... Opening 222 ... Diameter expansion part 223 ... Contact spring 23 ... Second cylindrical antenna element 231 ... Opening 232 ... Bottom 233 ... Plate-like part 234 ... Hole 3 ... Holding part 31 ... Upper pipe 311 ... Plate-like part 312 ... Hole 313 ... Pin 314 ... Locking body 315 ... Elastic material 32 ... Upper end coupling portion 321 ... First small diameter portion 322 ... Second small diameter portion 323 ... Intermediate flange portion 33 ... Lower pipe 34 ... Lower end coupling portion 341 ... Small diameter portion 342 ... Large diameter portion 35 ... Insulating tube 351 ... Upper end flange portion 36 ... Coil 4 ... Holder 51, 52 ... Capacitor 6 ... Feeder

Claims (9)

A telescopic rod-shaped antenna element part,
A holding portion that holds the antenna element portion in a bendable manner;
Have
The holding part is
A substantially cylindrical antenna element conducting portion provided to conduct with the antenna element portion;
A substantially cylindrical power supply conducting part provided to conduct with the power supply part;
An insulating cylinder that is substantially internal to the power supply conduction portion and is interposed between the antenna element conduction portion and the power supply conduction portion;
A coil that is arranged inside the insulating cylinder so that the axial direction is aligned with the insulating cylinder, and is coupled with the upper end portion being conducted to the antenna element conducting portion and the lower end portion being conducted to be coupled to the feeding conducting portion,
A multi-frequency shared antenna comprising: The power supply conduction part is
A lower pipe sheathed by the insulating cylinder;
A lower end coupling portion fixed so as to close the bottom side of the lower pipe,
The multi-frequency shared antenna according to claim 1, wherein a lower end portion of the coil is coupled to the lower end coupling portion at a position away from a central axis of the lower pipe.   3. The multi-frequency shared antenna according to claim 2, wherein the lower end coupling portion has a small diameter portion engaged with the lower pipe, and a large diameter portion contacting the lower end of the lower pipe. The antenna element conducting portion is
An upper pipe in which a stationary mechanism that holds the antenna element portion at the upper end portion in a bendable manner and urges the antenna element portion to be placed at a required position is provided;
An upper end coupling portion provided so as to close the bottom side of the upper pipe,
The multi-frequency shared antenna according to claim 1, wherein an upper end portion of the coil is coupled to the upper end coupling portion. The upper end coupling portion is between a first small diameter portion engaged in the upper pipe, a second small diameter portion engaged in the insulating cylinder, and between the first small diameter portion and the second small diameter portion. And an intermediate flange that contacts the lower end of the upper pipe,
At the upper end of the insulating cylinder, an upper end collar portion that comes into contact with the upper end of the power supply conduction portion is provided,
The multi-frequency shared antenna according to claim 4, wherein the upper end flange portion of the insulating cylinder and the intermediate flange portion of the upper end coupling portion are in contact with each other.   The multi-frequency shared antenna according to any one of claims 1 to 5, wherein an inner peripheral surface of the insulating cylinder and the coil are provided apart from each other.   The antenna element section according to any one of claims 1 to 6, wherein the antenna element on the front end side has a small diameter in the extended state, or the antenna element on the front end side has a large diameter in the extended state. Frequency sharing antenna. A method for manufacturing a multi-frequency antenna according to claim 3,
In a state where the lower end portion of the coil is coupled to the small diameter portion of the lower end coupling portion at a position away from the central axis of the lower pipe, and the small diameter portion is engaged in the lower pipe, A step of adjusting the resonance state with respect to a predetermined resonance frequency by rotating the lower end coupling portion as required by the inspection result;
A method for manufacturing a multi-frequency antenna. A portable terminal comprising the multi-frequency shared antenna according to claim 1.

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