JP2006093998A - Mobile communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of a conventional slide type mobile phone that cannot help employing a long flexible cable that the antenna impedance characteristic is fluctuated due to an extended electric length of the flexible cable resulting in deteriorating the communication characteristic. <P>SOLUTION: A flexible cable 10 for electrically connecting circuit boards of an upper case 1 and a lower case 2 for configuring the slide type mobile phone is connected to ground of the board 17 inside the lower case 2 at a proper position between connectors 26, 27 at both ends to reduce the electric length of the flexible cable 10 thereby enhancing the antenna impedance characteristic. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a portable communication device having an upper casing provided with a display unit and a receiver, and a lower casing provided with an operation unit and a transmitter, and in particular, an upper casing and a lower casing. The present invention relates to a slide-type mobile phone that is slidably coupled.

  In the slide-type mobile phone, an upper housing having a display unit and a receiving unit and a lower housing having an operation unit and a transmitting unit are relatively moved in parallel. Then, from the “closed state” where the display and receiver of the upper casing are exposed and the operating section of the lower casing is covered by the upper casing, the display and receiver and lower casing of the upper casing are operated. It shifts to the “open state” where both parts are exposed. In order to realize such an operation, the slide type mobile phone has a slide mechanism that slidably couples the upper housing and the lower housing.

  In addition, circuit boards are stored in the upper casing and the lower casing, respectively, and the circuit boards in the upper casing and the lower casing use “inter-casing connection cables” such as flexible cables. Are electrically connected. Connectors are provided at both ends of the flexible cable, and the flexible cable connector is fitted to the connector provided on the circuit board inside the upper and lower casings, so that the inside of the upper and lower casings. It is possible to exchange electrical signals between the circuit boards. A general configuration of the slide-type mobile phone is disclosed in Patent Document 1.

Japanese Patent Laid-Open No. 2002-3000243

  By the way, in the case of a slide-type mobile phone, the length of the flexible cable must be secured between the lower casing and the upper casing, and further, depending on the connector position on the circuit board, It must be formed long. However, when the flexible cable becomes longer, the electrical length becomes longer, so that it is difficult to keep the antenna impedance good, and there is a problem that the antenna performance is affected.

  Therefore, the present invention provides a slide-type mobile phone in which a flexible cable has to be formed long and the electrical length of the flexible cable is shortened to improve the antenna impedance characteristics and realize good communication performance. The purpose is to provide.

  A portable communication device according to the present invention is mounted with an electronic component, and is formed by laminating a plurality of conductive layers and an insulating layer, and a predetermined conductive layer among the plurality of conductive layers is grounded. A first substrate having a ground layer and an electronic component are mounted, and a plurality of conductive layers and an insulating layer are stacked, and a predetermined conductive layer of the plurality of conductive layers is grounded. A second substrate as a ground layer, an electronic component mounted on the first substrate, a signal line for transmitting an electrical signal between the electronic components mounted on the second substrate, a ground layer of the first substrate, A ground line for connecting the ground layer of the second substrate, a connection portion for electrically connecting the signal line and the ground line to the first substrate and the second substrate, respectively, at a position separated from the connection portion by a predetermined length. Gradually connected to the ground line Has a de connection unit is obtained by providing a cable, which is grounded to the first substrate via the ground connecting portion.

  A portable communication device according to the present invention is mounted with an electronic component, and is formed by laminating a plurality of conductive layers and an insulating layer, and a predetermined conductive layer among the plurality of conductive layers is grounded. A first substrate having a ground layer and an electronic component are mounted, and a plurality of conductive layers and an insulating layer are stacked, and a predetermined conductive layer of the plurality of conductive layers is grounded. A second substrate as a ground layer, an electronic component mounted on the first substrate, a signal line for transmitting an electrical signal between the electronic components mounted on the second substrate, a ground layer of the first substrate, A ground line for connecting the ground layer of the second substrate, a connection portion for electrically connecting the signal line and the ground line to the first substrate and the second substrate, respectively, at a position separated from the connection portion by a predetermined length. Gradually connected to the ground line It has a de connecting portion, since there is provided a cable which is grounded to the first substrate via the ground connecting portion, the electrical length of the cable is shortened. Therefore, the antenna impedance is improved and the communication performance is improved.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below. FIG. 1 is an external perspective view showing an external appearance of a slide type mobile phone. FIG. 1A shows a slide type mobile phone in a state in which an upper housing 1 and a lower housing 2 are closed. In the state where the upper housing 1 and the lower housing 2 are closed as shown in FIG. 1A, the display unit 3 and the receiver 4 of the upper housing 1 are exposed, and the operation unit 5 of the lower housing 2 is exposed. Is covered by the upper housing 1. FIG. 1B shows a slide type mobile phone in a state where the upper casing 1 and the lower casing 2 are opened. In the state where the upper casing 1 and the lower casing 2 are opened as shown in FIG. 1B, the display section 3 and the receiving section 4 of the upper casing 1 and the operation section 5 and the transmitting section 6 of the lower casing 2 are displayed. Are both exposed.

  FIG. 2 is an exploded perspective view of the slide type mobile phone. An upper housing 1 shown in FIG. 2 is configured by mounting an electronic component inside an upper housing case 8 facing the lower housing 2 and assembling an upper housing cover 9 to the upper housing case 8. On the back side facing the lower housing 2 of the upper housing case 8, a cable lead-out hole 11 that penetrates the inside and the outside of the upper housing case 8 and leads out the flexible cable 10 is formed. A slide rail 12 and a slider 15 slidably fitted to the slide rail 12 are provided on the back side of the upper housing case 8. The lower housing cover 13 is slidably assembled to the upper housing 1 configured as described above by a slider fixing portion 16 (slider fixing screw). The lower housing cover 13 is formed with a cable introduction hole 14 that penetrates the inside and outside of the lower housing cover 13 and draws the flexible cable 10 led out from the upper housing 1 into the lower housing cover 13. Yes. The cable lead-out hole 11 and the cable introduction hole 14 are formed long in the longitudinal direction of the casing so that the bending position of the flexible cable 10 can be moved when the upper casing 1 and the lower casing 2 slide. . In FIG. 2, the same reference numerals as those in FIG.

  FIG. 3 is an exploded perspective view of the slide type mobile phone. The exploded perspective view shown in FIG. 3 shows a state in which the lower housing cover 13 is assembled to the upper housing 1 by the slider fixing portion 16, and further shows a state in which the substrate 17 is mounted. On the substrate 17 shown in FIG. 3, a metal frame for covering various electronic components mounted on the substrate 17 is provided. The metal frame 18 prevents unnecessary radiated waves radiated from various electronic components mounted on the substrate 17 from being radiated to the outside, and prevents noise mixed from outside from affecting the various electronic components. It functions as a shield box (shield member) that shields various electronic components. In general, the substrate 17 is formed by alternately laminating a plurality of conductive layers and a plurality of insulating layers. More specifically, a ground layer (conductive layer) for various electronic components on the substrate 17, a ground layer for the metal frame 15, and an insulating layer that insulates these conductive layers are alternately stacked. The electronic component of the substrate 17 is grounded to the ground layer for the electronic component, and the metal frame 15 is grounded to the ground layer for the metal frame.

  A function as an antenna can be provided by grounding the metal frame 15 and the ground layer for the metal frame. In other words, the metal frame 15 functions as a shield box that electronically shields various electronic components and functions as an antenna. The metal frame 15 is insulated from the user's hand by the resin casing. Further, the substrate 17 has power supply pins 19 for supplying power to a built-in antenna (not shown) (main antenna 22 described later). If the built-in antenna electrically connected to the feed pin 19 is designed to have a length corresponding to λ / 4 of the operating frequency, for example, the built-in antenna operates as a monopole antenna having an electrical length of about λ / 4. On the other hand, since the metal frame 15 operates as an antenna corresponding to λ / 4 by being configured as described above, the built-in antenna and the metal frame 15 form a radiation pattern equivalent to a λ / 2 dipole antenna as a whole. The flexible cable 10 is electrically connected to the substrate 17 via a connector to be described later, and exchanges electrical signals with various electronic components on the substrate 17.

  FIG. 4 is an external view showing a connection state of the flexible cable to the substrate. 4, the same reference numerals as those in FIG. 2 and FIG. 3 indicate the same or corresponding parts, and the description thereof will be omitted. The flexible cable 10 has a connector 26 connected to the substrate 17 on the lower housing 2 side and a connector 27 connected to the substrate 20 on the upper housing 1 side at both ends. The board 17 and the board 20 are provided with a connector connecting portion (not shown in FIG. 4), and the connector connecting portion on the board side and the connectors 26 and 27 of the flexible cable 10 are fitted. With this configuration, the substrate 20 of the upper housing 1 and the substrate 17 of the lower housing 2 are electrically connected via the flexible cable 10, and the electronic components mounted on the substrate 20 and the substrate 17 are connected. It becomes possible to exchange electrical signals.

  FIG. 5 is a cross-sectional view showing a cross section of a general slide-type mobile phone. FIG. 5A shows a state where the upper housing 1 and the lower housing 2 are opened, and FIG. 5B shows a state where the upper housing 1 and the lower housing 2 are closed. FIG. 5 shows that the upper housing side substrate 20 and the upper housing side metal frame 21 are provided inside the upper housing 1. The upper housing side substrate 20 and the upper housing side metal frame 21 are configured to correspond to the substrate 17 and the metal frame 18 inside the lower housing 2. FIG. 5 shows that the connector of the flexible cable 10 is connected to a connector connecting portion 23 provided on the substrate 17 and the upper housing side substrate 20 respectively. For convenience of the following description, the connector connecting portion provided on the substrate 17 on the lower housing side is referred to as 23a, and the connector connecting portion provided on the substrate 20 on the upper housing side is referred to as 23b. The electrical length of the flexible cable 10 shown in FIG. 4 is substantially the same as the length of the flexible cable 10 because it is not grounded between the connector connecting portions 23a and 23b. Although it depends on the shape of the slide type mobile phone to be applied, the length of the flexible cable is about 80 mm.

  On the other hand, FIG. 6 is a sectional view showing a section of the slide type mobile phone according to the first exemplary embodiment of the present invention. In FIG. 6, the same reference numerals as those shown in FIG. The slide type mobile phone shown in FIG. 6 is one that is electrically connected to the ground layer of the substrate 17 and grounded in the middle of the flexible cable 10 that connects between the connector connecting portions 23a and 23b. The ground portion 25 on the flexible cable 10 is grounded via the conductive cushion 24. Thus, by grounding the flexible cable 10 in the middle, the electrical length of the flexible cable becomes equal to the length between the grounding portion 25 and the connector connecting portion 23b, not the length between the connector connecting portions 23a and 23b. That is, since the electrical length is shortened by the length between the connector connecting portion 23a and the connecting portion 25 as compared with the electrical length of the flexible cable of the slide type mobile phone shown in FIG. 5, the antenna impedance is improved.

  FIG. 7 is a plan view showing a configuration of a flexible cable applied to the slide type mobile phone according to the first exemplary embodiment of the present invention. In FIG. 7, the same reference numerals as those shown in FIG. A flexible cable 10 shown in FIG. 7A has connectors 26 and 27 at both ends of a flexible substrate having flexibility. On the flexible board between the connectors 26 and 27, for example, about 40 signal lines 28 for transmitting electrical signals exchanged between the electronic components incorporated in the upper housing 1 and the lower housing 1 are formed. ing. Further, the flexible cable 10 shown in FIG. 7 has a ground signal line 30 for grounding the substrates of the upper housing 1 and the lower housing 2 so as to sandwich the end portion in the width direction of the flexible substrate, that is, the signal wire 28. Arranged. And the ground connection part 31 electrically connected with this ground signal wire | line 30 is provided so that it may protrude in the width direction of a flexible cable. The ground connection portion 31 is a portion that is electrically connected to the ground layer of the substrate 17 of the lower housing 2 via the conductive cushion 25. That is, the flexible cable 10 shown in FIG. 7 is grounded to the ground layer of the lower housing side substrate 17 through the ground connection portion 31 and the conductive cushion 25.

  The flexible cable shown in FIG. 7B is provided with a metal film 31 that covers the surface of the flexible cable shown in FIG. 7A, that is, the surface on which the signal line 28 and the ground line 29 are provided. . The metal coating 31 suppresses unnecessary radiation waves radiated from the signal line 28 and the ground line 29 of the flexible cable from affecting external devices, and noise from the outside is mixed into the signal line 28 and the ground line 29. It fulfills the function of deterring. The metal film 31 may be formed using, for example, an aluminum thin film. The ground connection portion 31 is formed at a position a that is long enough to be led out from the connector 26 on the lower housing 1 side to the outside of the lower housing 1. Further, the length b from the ground connection portion 30 to the upper housing 1 side connector 27 is in a state where the length b is derived from the lower housing 2 and connected to the substrate 21 of the upper housing 1. A sufficient length is required for the lower housing 2 to slide. That is, the formation position of the ground connection portion 30 of the flexible cable 10 is the length from the lower housing side connector 26 to the outside of the lower housing 2 and the upper housing 1 and the lower housing 2 with the ground connection portion 30 fixed. Is determined in consideration of the length necessary for sliding without any problem.

  FIG. 8 is an explanatory view illustrating a configuration for attaching the conductive cushion to the substrate. As shown in FIG. 8A, a ground portion 32 where the ground is exposed is provided on a part of the substrate 17. Then, as shown in FIG. 8B, the conductive cushion 24 is grounded to the ground portion 32 of the substrate 17. As shown in FIG. 8C, the conductive cushion 24 is coated with an adhesive 33 on the surface facing the ground portion 32, and the conductive cushion 24 is fixed to the ground portion 32 by the adhesive force of the adhesive 33. Is done. FIG. 9 is an explanatory view illustrating a configuration in which the ground connection portion 30 of the flexible cable 10 is connected to the conductive cushion 24 fixed to the ground portion of the substrate 17 as described above. The conductive cushion 24 is made of fiber, rubber, resin, or the like mixed with a conductive material. The flexible cable 10 is connected to the ground of the substrate 17 via the conductive cushion 24 by connecting the ground connection portion 30 connected to the ground line 29 of the flexible cable 10 to the conductive cushion 24.

  As described above, the flexible cable 10 that electrically connects the circuit boards of the upper housing 1 and the lower housing 2 has been described in the present embodiment at an appropriate position between the connectors 26 and 27 at both ends. In the example, the electrical length of the flexible cable 10 is shortened by grounding to the ground of the substrate 17 inside the lower housing 2. Therefore, the antenna impedance is improved and the communication performance is improved. FIG. 10 is an explanatory diagram for explaining an example of the effect of the slide type mobile phone according to the first exemplary embodiment of the present invention. The table shown in FIG. 10 shows the communication efficiency in each frequency band before the flexible cable 10 is grounded (before improvement) and after the flexible cable 10 is grounded (after improvement). FIG. 10 shows that the frequencies are 810 MHz, 843 MHz, and 885 MHz, and the efficiency is improved by 1.5 dB, 1.0 dB, and 0.2 dB, respectively, before and after improvement. Moreover, FIG. 11 is explanatory drawing explaining an example of the effect of the slide type | mold mobile telephone concerning Embodiment 1 of this invention. In the graph shown in FIG. 11, the vertical axis indicates “return loss (dB)” which is one of the parameters indicating communication efficiency, and the horizontal axis indicates the length (electric length) of the flexible cable. The return loss on the vertical axis indicates that the communication efficiency is better as it is distributed on the origin side. According to FIG. 11, if the length of the flexible cable is about 50 to 65 mm, the return loss is small and the antenna impedance is good. However, if the length is 70 mm or more, the return loss increases and the antenna impedance is It has been shown to get worse.

  In the above description, the flexible cable 10 is connected to the ground portion 32 provided on the substrate 17 of the lower housing 2, thereby grounding the flexible cable 10 to the substrate 17 and shortening the electrical length. However, it may be configured not to connect to the ground portion 32 of the substrate 17 but to connect to the metal frame 15. Since the metal frame 15 is grounded to the ground layer of the substrate 17, the flexible cable 10 is grounded via the metal frame 15.

  In the above description, the flexible cable 10 is grounded on the lower housing 2 side, but may be grounded on the upper housing 1 side. Even when the flexible cable 10 is grounded on the upper housing 1 side, the electrical length of the flexible cable 10 can be reduced by grounding the ground portion of the substrate 20 or the metal frame 21 on the substrate 1 side.

  In the above description, the flexible cable 10 is connected to the ground portion 32 using the conductive cushion 24. However, instead of the conductive cushion 24, the flexible cable 10 uses a conductive spring 34 as shown in FIG. Also good. Similarly to the conductive cushion 24, the conductive pin 35 shown in FIG. 13, the conductive clip 36 shown in FIG. 14, the solder 37 shown in FIG. 15, and the conductive screw 38 shown in FIG. The effect of.

It is an external appearance perspective view which shows the external appearance of a slide type mobile telephone. It is a disassembled perspective view of a slide type mobile phone. It is a disassembled perspective view of a slide type mobile phone. It is an external view which shows the connection condition to the board | substrate of a flexible cable. It is sectional drawing which shows the cross section of a common slide type mobile telephone. It is sectional drawing which shows the cross section of the slide type mobile telephone concerning embodiment of this invention. It is a top view which shows the structure of the flexible cable applied to the slide type mobile telephone concerning embodiment of this invention. It is explanatory drawing explaining the structure which attaches a conductive cushion to a board | substrate. It is explanatory drawing explaining the structure which earth | grounds a flexible cable to a board | substrate via a conductive cushion. It is explanatory drawing explaining an example of the effect of the slide type mobile telephone concerning embodiment of this invention. It is explanatory drawing explaining an example of the effect of the slide type mobile telephone concerning embodiment of this invention. It is sectional drawing which shows the modification of the slide type mobile telephone concerning embodiment of this invention. It is sectional drawing which shows the modification of the slide type mobile telephone concerning embodiment of this invention. It is sectional drawing which shows the modification of the slide type mobile telephone concerning embodiment of this invention. It is sectional drawing which shows the modification of the slide type mobile telephone concerning embodiment of this invention. It is sectional drawing which shows the modification of the slide type mobile telephone concerning embodiment of this invention.

Explanation of symbols

1 upper casing, 2 lower casing, 3 display section, 4 receiving section, 5 operating section, 6 transmitting section,
7 slide type mobile phone, 8 upper case, 9 upper case cover,
10 Flexible cable, 11 Cable outlet hole, 12 Slide rail,
13 Lower housing cover, 14 Cable introduction hole, 15 Slider, 16 Slider fixing part,
17 substrate, 18 metal frame, 19 power supply pin, 20 upper housing side substrate,
21 upper housing side metal frame, 22 main antenna, 23 connector connection,
24 conductive cushion, 25 grounding part, 26 lower housing side connector,
27 Upper housing side connector, 28 signal line, 29 ground line, 30 ground connection part,
31 metal film, 32 ground portion, 33 adhesive, 34 conductive spring,
35 conductive pins, 36 conductive clips, 37 solder, 38 conductive screws

Claims (6)

A first substrate on which an electronic component is mounted, and is formed by laminating a plurality of conductive layers and insulating layers, and having a predetermined conductive layer as a ground layer for grounding among the plurality of conductive layers When,
A second substrate on which an electronic component is mounted, and is formed by laminating a plurality of conductive layers and insulating layers, and having a predetermined conductive layer as a ground layer for grounding among the plurality of conductive layers When,
A signal line for transmitting an electric signal between the electronic component mounted on the first substrate and the electronic component mounted on the second substrate; a ground layer of the first substrate; and a ground layer of the second substrate A ground line that connects the signal line and the ground line to the first substrate and the second substrate, respectively, and the ground line at a position spaced apart from the connection portion by a predetermined length. A portable communication device comprising a ground connection portion electrically connected, and a cable grounded to the first substrate via the ground connection portion. 2. The cable according to claim 1, wherein the cable is grounded to the first substrate by causing the ground connection portion to conduct with the ground portion electrically connected to the ground layer of the first substrate. Mobile communication device. The portable communication device according to claim 2, wherein the cable is installed on the first board by bringing the ground connection part into contact with a conductive member disposed on the ground part of the first board. . The first substrate includes a metal shield member that electromagnetically shields the electronic component, and electrically connects the shield member to a predetermined ground layer among a plurality of ground layers, thereby The portable communication device according to claim 1, wherein the portable communication device is grounded. The portable communication device according to claim 4, wherein the cable is grounded to the first substrate by causing the ground connection portion to conduct to the shield member. The first substrate is formed with at least a radio circuit as a mounted electronic component, and a power feeding unit to an antenna that transmits a signal transmitted from the radio circuit to the outside, and the first substrate is provided in a lower casing provided with the antenna. The built-in second substrate is built in at least an upper housing having a display unit, and the lower housing and the upper housing are slidably coupled to each other. The portable communication device according to any one of claims 5 to 6.

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