JP2009044437A - Collective electric wire, coil antenna, and portable radio apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a collective electric wire, etc. capable of enhancing a working property upon a wire connection. <P>SOLUTION: The collective electric wire 3-1 is a collective electric wire obtained by collecting insulating electric wires 2a to 2c formed by coating an insulating layer 6 on a conductor 5, and of these, the insulating electric wire 2c is constituted of only the conductor 5 and is not coated with the insulating layer 6. Further, a conductor diameter of the insulating electric wire not coated with the insulating layer is greater than the conductor diameter of the other insulating electric wires coated with the insulating layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improved technique of a coil antenna used for portable radio equipment such as an IC card and a mobile phone, and more specifically, a collective wire composed of a plurality of insulated wires, and a coil antenna constituted by the collective wires. The present invention also relates to a portable wireless device including the coil antenna.

Conventionally, an electronic device such as an IC card or a mobile phone has a built-in communication antenna. As an example of the built-in antenna, there is a coil antenna using electromagnetic induction. As a conventional technique related to this coil antenna, a coil antenna has been proposed in which a plurality of insulated wires are twisted together, a collective wire covering a jacket layer serving as a jacket is connected to a substrate, and the whole is formed into an annular shape ( Patent Document 1).
JP 2006-191194 A

  In the coil antenna proposed in Japanese Patent Application Laid-Open No. 2006-191194, two types of jackets are required: an insulating layer for each insulated wire and an outer jacket layer. For this reason, when connecting, it is necessary to peel off two types of jackets of the insulating layer and the jacket layer, and it takes time and effort to connect.

  Moreover, in a mobile phone etc., since the installation space of a coil antenna has restrictions, it is necessary to make the conductor diameter of an insulated wire thin. However, if the conductor diameter is reduced, the conductor resistance of the insulated wire is increased and the Q value of the coil is lowered, so that the characteristics as a coil antenna are deteriorated.

  Furthermore, in mobile phones and the like, further downsizing is required. However, if the outer circumference of the collective wire is large, it is difficult to save the installation position.

  An object of the present invention is to provide a collective electric wire that can improve workability during connection. In addition, it aims at providing the coil antenna comprised by this assembly electric wire, and the portable radio | wireless apparatus provided with this coil antenna.

  Another object of the present invention is to provide a collective electric wire that can improve workability and antenna characteristics during connection. In addition, it aims at providing the coil antenna comprised by this assembly electric wire, and the portable radio | wireless apparatus provided with this coil antenna.

  Still another object of the present invention is to provide a collective electric wire that can improve workability during connection and can save space. In addition, it aims at providing the coil antenna comprised by this assembly electric wire, and the portable radio | wireless apparatus provided with this coil antenna.

  In order to achieve the above object, the invention of claim 1 is a collective electric wire in which a plurality of insulated electric wires each having a conductor covered with an insulating layer are collected and the outer periphery thereof is covered with a jacket layer. Among the electric wires, one of the insulated wires is not covered with an insulating layer.

  The gist of the invention of claim 2 is that, in claim 1, the conductor diameter of the insulated wire not covered with the insulating layer is larger than the conductor diameter of the other insulated wires covered with the insulating layer.

  The gist of the invention of claim 3 is that, in claim 1, the conductor diameter of the insulated wire not covered with the insulating layer is the same as the conductor diameter of the other insulated wires covered with the insulating layer. To do.

  The invention of claim 4 is an annular coil antenna for the purpose of communication by electromagnetic induction, and is summarized in that the collective wire according to any one of claims 1 to 3 is used.

  A fifth aspect of the present invention is a portable wireless device characterized in that the coil antenna according to the fourth aspect is mounted in a casing.

  According to the present invention, since one insulating wire is not covered with an insulating layer among a plurality (n) of insulated wires, (n-1) insulating layers when connecting, It is only necessary to peel off one jacket layer, and the connection can be performed easily and in a short time, so that workability can be improved.

  Moreover, the conductor resistance of the whole insulated wire can be made small by making the conductor diameter of the insulated wire which is not coat | covered with an insulating layer larger than the conductor diameter of another insulated wire. As a result, the Q value of the coil can be increased, and the characteristics as a coil antenna can be improved, for example, the communication distance can be extended.

  Also, by making the conductor diameter of the insulated wires not covered with the insulating layer the same as the conductor diameter of other insulated wires, the outer dimensions of the aggregated wires can be reduced, and the installation position can be saved. Can be planned.

  Hereinafter, embodiments of a collective wire, a coil antenna, and a portable wireless device according to the present invention will be described.

  FIG. 1 is an overall view of a coil antenna according to an embodiment. As shown in FIG. 1, the coil antenna 1 according to the present embodiment is configured as a whole by connecting a collective wire 3 in which three insulated wires 2 (2a, 2b, 2c) are gathered to a circuit board 4. It is comprised so that it may become cyclic | annular.

  By mounting such a coil antenna 1 in a casing of a portable wireless device (not shown) such as an IC card or a mobile phone, communication by electromagnetic induction becomes possible. For example, in the case of an IC card, data stored in the card can be rewritten and saved by a card reader / writer (not shown). In addition, if it is a mobile phone, data communication such as voice, image, or text information can be performed with a partner mobile phone or a service provider by transmitting and receiving radio signals to and from the nearest base station. It can be carried out.

  FIG. 2 is a cross-sectional view of the collective wire according to the present embodiment, and corresponds to a cross section taken along line AA of FIG. FIG. 3 is a cross-sectional view of a collective wire (conventional example) in which all insulated wires are covered with an insulating layer.

  As shown in FIG. 2, the collective electric wire 3-1 according to the present embodiment is an assembly of three insulated electric wires 2a, 2b, and 2c in a triangular shape. Of these three insulated wires 2a, 2b, 2c, the insulated wires 2a, 2b are composed of a conductor 5 and an insulating layer 6 coated on the surface of the conductor 5. Moreover, the insulated wire 2c is comprised only with the conductor 5, and the insulating layer 6 is not coat | covered. And the conductor diameter of the insulated wire 2c is comprised so that it may become a diameter larger than the conductor diameter of the other insulated wires 2a and 2b. These insulated wires 2 a to 2 c are gathered by being twisted together, and the outer periphery thereof is covered with a jacket layer 7. Thereby, the three insulated wires 2 are integrated and configured as one collective wire 3-1.

  Here, a copper wire or the like is used as the conductor 5. The conductor 5 of the insulated wire 2c is the same diameter as or thicker than the conductor diameter of the conductors 5 of the other insulated wires 2a and 2b, and is the same diameter or smaller than the insulated wire diameter of the insulated wires 2a and 2b. As the insulating layer 6, a polyolefin-based resin is used. As the jacket layer 7, it is preferable to use a fluororesin such as PTFE, ETFE, or FEP. However, the constituent material of each part is not limited to the example of this embodiment, It can comprise with the other material provided with the equivalent characteristic and the property.

  According to the collective wire 3-1 according to the present embodiment, since the insulated wire 2c is not covered with the insulating layer 6 among the three insulated wires 2a to 2c, the insulated wires 2a and 2b are connected at the time of connection. The insulation layer 6 and the jacket layer 7 may be peeled off, and as shown in FIG. 3, connection is easily and quickly performed as compared with the configuration in which the insulation layer 6 is covered on all the insulated wires 2 a to 2 c. be able to.

  Moreover, since the conductor diameter of the insulated wire 2c which is not coat | covered with the insulating layer 6 was made larger than the conductor diameter of the other insulated wires 2a and 2b, the conductor resistance of the whole insulated wire can be made small. As a result, the Q value of the coil can be increased, and the characteristics as a coil antenna can be improved, for example, the communication distance can be extended.

  In addition, when the conductor diameter of the insulated wire 2c which is not coat | covered with the insulating layer 6 is enlarged, the discrimination | determination of the electric wire at the time of connection will become easy. That is, in FIG. 1, when the conductor diameters of the three insulated wires 2a to 2c are the same, in order to distinguish each wire, all three colors are changed to different colors or one of the three wires. Need to be different color. However, in this embodiment, one of the three wires (insulated wire 2c) can be readily identified, and the remaining two wires are checked for continuity at both ends during wiring. When there is no continuity, it can be determined as a different line. Therefore, the process of color-coding the electric wires is not necessary, and the cost can be reduced.

  Next, how much the Q value of the coil is improved by the configuration of the present embodiment will be described.

  For example, when the outermost diameter of the collecting wire is 0.75 mm and the thickness of the insulating layer and the jacket layer is 0.05 mm, respectively, in the configuration in which all the insulating wires are covered with the insulating layer as shown in FIG. The conductor diameter of the insulated wire is 0.20 mm. On the other hand, in a configuration in which only one insulated wire is not covered with the insulating layer, the conductor diameter of the insulated wire is 0.30 mm (other conductor diameter is 0.20 mm). Under such conditions, if the conductor resistance of an insulated wire with a conductor diameter of 0.20 mm is R, the conductor resistance of the aggregate wire when all three wires are insulated wires is the sum of the conductor resistance values of the three wires. 3R.

The equation representing the DC resistance R of the conductor is R = ρ · l / S (where ρ: conductivity, l: length, S: cross-sectional area). At this time, when the conductor diameter of the uncovered electric wire is 0.30 mm as described above, it is inversely proportional to the cross-sectional area ratio when compared with the DC resistance of the insulated electric wire having a conductor diameter of 0.20 mm. The resistance value of 30 mm is R × π · 0.20 ² /π·0.30 ² = 0.44R. Therefore, the conductor resistance of the collective wire that does not insulate one of the three conductors is R + R + 0.44R = 2.44R, and 2.44 / 3 = 0.81 compared to the collective wire that insulates all three. Thus, the conductor resistance is reduced to 81%.

  Next, the Q value (no load) of the coil in the insulated wire in which all three are covered with the insulating layer is obtained. The equation is Q = ω · L / R (ω: angular frequency, L: inductance of coil, R: DC resistance of coil).

  Of these, the DC resistance is reduced to 81% according to the above calculation. On the other hand, as shown in Table 1, it has been confirmed by experiments that the inductance of the coil does not change much even when the conductor diameter is increased. Therefore, assuming that the inductance is constant, among the Q value of the coil = ω · L / R, ω and L can be regarded as constant values, and only R needs to be considered.

  That is, since (ω · L / R) / (ω · L / R ′) = R / R ′ = 1 / 0.81 = 1.23, the Q value increases by about 23%.

Therefore, for example, the Q value of a Φ40 mm coil made of a collecting wire made up of three insulated wires having a conductor diameter of 0.20 mm is about 60, so that the Q value is 23% by adopting the configuration of this embodiment. It rises about 73% of the increase.

  Therefore, for example, the Q value of a Φ40 coil made of a collective wire made up of three insulated wires having a conductor diameter of 0.20 mm is about 60. By adopting the configuration of this embodiment, the Q value is increased by 20%. It rises to about 72. Thus, according to the configuration of the present embodiment, the Q value of the coil can be increased, and the effect of improving the characteristics as a coil antenna can be expected.

  FIG. 4 is a cross-sectional view showing another configuration example of the collective wire according to the present embodiment. In the collective wire 3-2 according to the present embodiment, the conductor diameter of the insulated wire 2c not covered with the insulating layer 6 and the conductor diameters of the other insulated wires 2a and 2b are the same. Further, the jacket layer 7 has an elliptical shape in accordance with the outer shapes of the insulated wires 2a to 2c. Thereby, in this embodiment, the outer periphery dimension of the collection electric wire 3-2 becomes small, and the cross-sectional area is small compared with the structure of FIG. 4 as the whole electric wire.

  Also in the collective wire 3-2 according to the present embodiment, the insulation layer 6 and the jacket layer 7 of the insulated wires 2a and 2b may be peeled off at the time of connection, so that the connection can be performed easily and in a short time. it can. In particular, in this embodiment, since the conductor diameter of all the insulated wires is made the same, the outer periphery dimension of the assembly wire 3-2 can be made small, and the installation position can be saved.

  As described above, according to the aggregated electric wire according to the present embodiment, one of the three insulated wires 2a to 2c is not covered with an insulating layer, so that when connecting, The insulating layer 6 and the jacket layer 7 of the insulated wires 2a and 2b may be peeled off. For this reason, it becomes possible to perform connection easily and in a short time, and workability | operativity can be improved.

  In particular, by making the conductor diameter of the insulated wire 2c not covered with the insulating layer 6 larger than the conductor diameter of the other insulated wires 2a and 2b covered with the insulating layer 6, the conductor resistance of the entire insulated wire can be reduced. Can be small. As a result, the Q value of the coil can be increased, and the characteristics as a coil antenna can be improved, for example, the communication distance can be extended.

  Further, by making the conductor diameter of the insulated wire 2c not covered with the insulating layer 6 and the conductor diameter of the other insulated wires 2a and 2b covered with the insulating layer 6 the same, Can be reduced, and the installation position can be saved.

  In addition, although the said embodiment demonstrated the example which aggregated the three insulated wires 2 (2a, 2b, 2c), the number of insulated wires is not limited to this example. That is, if it is a parallel line, it is good also as a structure provided with the insulated wire of 2 or 4 or more.

The whole figure of the coil antenna concerning an embodiment. Sectional drawing of the assembled wire concerning embodiment. Sectional drawing of the collection electric wire which coat | covered the insulating layer on all the insulated wires. Sectional drawing which shows the other structural example of the aggregated electric wire concerning embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Coil antenna 2 ... Insulated wire (2a, 2b, 2c)
3 ... Assembly wire (3-1, 3-2)
4 ... Circuit board 5 ... Conductor 6 ... Insulating layer 7 ... Jacket layer

Claims (5)

A plurality of insulated wires formed by covering a conductor with an insulating layer are assembled, and the outer periphery of the assembled wires is covered with a jacket layer,
Of the plurality of insulated wires, one insulated wire is not covered with an insulating layer.   The aggregated electric wire according to claim 1, wherein a conductor diameter of the insulated wire not covered with the insulating layer is larger than a conductor diameter of another insulated wire covered with the insulating layer.   The collective electric wire according to claim 1, wherein a conductor diameter of the insulated electric wire not covered with an insulating layer is the same as a conductor diameter of another insulated electric wire covered with the insulating layer. An annular coil antenna for communication by electromagnetic induction,
A coil antenna using the collective wire according to any one of claims 1 to 3.   A portable wireless device comprising the coil antenna according to claim 4 mounted in a housing.

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