The present invention relates to a portable radio that can be utilized for; for instance, a cell phone unit, a personal digital assistant (PDA), portable music player, a portable game machine, and others. More particularly, the present invention relates to a structure of a neighborhood of an electrical contact point between an antenna or an earth line and an electric circuit,
A portable radio like; for instance, a cell phone unit, has recently been required to exhibit waterproof capability. Related art techniques described in connection with; for instance, Patent Document 1, Patent Document 2, and Patent Document 3, already exist as a waterproof structure of a portable radio, or the like.
Patent Document 1 shows that a power feed protrusion is formed in a portion of power feed hardware (an antenna guide) that holds a whip antenna in a slidable manner and that the power feed protrusion is connected to a circuit board by way of a mutual communication hole by way of a waterproof gasket.
Patent Document 2 shows that an antenna conductor and an earth plane (an earth line) conductor are affixed to a waterproof seal and that the waterproof seal is brought into close contact with an overall outer circumference of an enclosure, to thus make the enclosure watertight. Moreover, the antenna conductor and the earth plane conductor are structured so as to be respectively, electrically connected to and supplied with electric power from a circuit hoard in an enclosure by way of a hole made in the outer circumference of the enclosure.
Patent Document 3 shows that an enclosure is made up of an upper case and a lower case. A frame-shaped waterproof gasket exists in a joint between the upper case and the lower case. An antenna element is configured so as to be embedded in the waterproof gasket.
Patent Document 1: JP-A-2009-010792
Patent Document 2: JP-A-7-99403
Patent Document 3: JP-A-6-37876
However, conventional techniques, such as those mentioned above, encounter difficulty in assuring waterproof characteristic in a neighborhood of the power feed sections; namely, a connection between a land (an exposed electrode) on the circuit board and the antenna element. Further, a connecting status may become unstable, or variations may also occur in antenna characteristics.
For instance, in the case of the technique describe connection with Patent Document 1, it is not easy to make the location at which the power feed protrusion passes through the mutual communication hole waterproof without fail and implement a stable connecting status. In the case of the technique described in connection with Patent Document 2, it is not easy to assure a stable connecting status at a location where the respective conductors and the circuit are connected together by way of the hole and to make the location waterproof without fail. In the case of the technique described in connection with Patent Document 3, assuring water-tightness is easy, but it is difficult to assemble the enclosure, which in to poses difficulty in mass-production of the enclosure. Further, since it becomes difficult to sustain uniformly the layout and shape of the antenna element, variations may occur in antenna characteristics.
The present invention aims at providing a portable radio that makes it easier to assure water-tightness in a vicinity of a power feed section and that can easily assure a stable connecting status between a conductor, like an antenna, and a circuit board.
A portable radio of the present invention Is directed toward a portable radio having an enclosure in which a first case and a second case are combined, the radio comprising: an annular resilient member sandwiched between the first case and the second case; a flexible printed board that is formed integrally with the annular resilient member and that is extended toward an area surrounded by the annular resilient member; an antenna section provided on the flexible printed board; a first power feed section provided on, the flexible printed board and electrically connected to the antenna section; a circuit board provided in the area surrounded by the annular resilient member; an electric circuit section provided on the circuit board; and a second power feed section electrically connected to the electric circuit section, wherein the first power feed section opposes the annular resilient member; and an inter-space dimension of an area interposed between the flexible printed board and a part of the enclosure opposing the flexible printed board is smaller than a thickness dimension of a part of the annular resilient member that is to be sandwiched in the area, the thickness dimension being achieved under no-load conditions, with respect to a direction where the annular resilient member is sandwiched.
In the portable radio, when the first case and the second case of the enclosure are combined together, the first power feed section is pressed in a sandwiching direction by means of resilient force developing in the annular resilient member. The first power feed section and the second power feed section are thereupon electrically connected together, and the antenna section and the electric circuit section are also electrically connected. Specifically, water-tightness of an area of connection and stable electric connectivity are assured by means of the resilient force of the annular resilient member.
In the portable radio of the present invention, the flexible printed board and the antenna section are extended at least up to a position, where the flexible printed board and the antenna section oppose the second power feed section, toward the area surrounded by the annular resilient member; and the second power feed section is provided on a surface of the circuit board opposing the first power feed section.
In the present portable radio, the power feed sections are provided on the circuit board, which makes it possible to curtail the number of components required to make a connection between the power feed sections. Thus, assembly of the portable radio also becomes facilitated.
In the portable radio of the present invention, at least a portion of the flexible printed board is formed in an annular shape along an inner circumference of the area surrounded by the annular resilient member, and a portion of the flexible printed board crosses the area surrounded by the annular resilient member.
In the present portable radio, a portion (a bridging section) of the flexible printed board is formed so as to cross the area surrounded by the annular resilient member. Hence, positions where the power feed sections are to be positioned can be aligned to each other with a high degree of accuracy. Specifically, since the first power feed section and the second power feed section are positioned at the location of the bridging section, positional accuracy is substantially determined by geometry of the flexible printed board. Accordingly, variations become less likely to arise in relative mount positions during assembly, so antenna characteristics become less susceptible to variations.
Moreover, in the portable radio of the present invention, the first power feed section or the second power feed section has a protrusion that exhibits electrical conductivity.
In the present portable radio, the first power feed section and the second power feed section can be electrically connected by the protrusion, which contributes to a reduction in the number of components and improvement in productivity.
The portable radio of the present invention further includes a power feed plate for electrically connecting the first power feed section to the second power feed section.
In the portable radio, since the first power feed section and the second power feed section are connected by way of the plate, a distance between the circuit and the antenna section can be increased. Specifically the antenna section is sufficiently spaced apart from a ground pattern on the circuit board, where antenna resistance to radiation can be enhanced, and high antenna characteristics can be assured.
In the portable radio of the present invention, the annular resilient member has an annular water proof section sandwiched between the first case and the second case and an auxiliary power feed section that extends from a portion of the annular waterproof section toward an area surrounded by the annular waterproof section, wherein a thickness dimension of the annular waterproof section is smaller than a thickness dimension of the auxiliary power feed section with respect to a direction in which the annular waterproof section is sandwiched.
In the present portable radio, water-tightness of the power feed sections and an electrical connection can be readily assured, respectively. Specifically, water-tightness can be assured by load that can be controlled by a thickness dimension of the annular waterproof section of the annular resilient member. Further, an electrical connection between the first power feed section and the second power feed section can be assured by of load that can be controlled by a thickness dimension of the auxiliary power feed section of the annular resilient member. Since the thickness dimension of the annular waterproof section is smaller than the thickness dimension of the auxiliary power feed section with respect to the direction in which the annular waterproof section is sandwiched; hence, appropriate load can be exerted on respective locations.
A portable radio of the present invention is also directed toward a portable radio having an enclosure that is a combination of a first case with a second case, the radio comprising: an annular resilient member sandwiched between the first case and the second case; a flexible printed board that is formed integrally with the annular resilient member and that extends toward an area surrounded by the annular resilient member; an earth line section laid on the flexible printed board; a first electrical connection section that is provided on the flexible printed board and that is electrically connected to the earth line section; a circuit board set in the area surrounded by the annular resilient member; a ground section laid on the circuit board; and a second electrical connection section electrically connected to the ground section, wherein the first electrical connection section opposes the annular resilient section; and an area of spacing interposed between the flexible printed board and a part of the enclosure opposing the flexible printed board is smaller than a thickness dimension of a part of the annular resilient member that is to be sandwiched in the area of spacing, the thickness dimension being achieved under no-load conditions, with respect to a direction where the annular resilient member is sandwiched.
In the portable radio, when the first case and the second case of the enclosure are combined together, the first electrical connection section and the second electrical connection section are pressed by the resilient force developing in the annular resilient member with respect to the direction in which the annular resilient member is sandwiched. The earth line section and the ground section on the circuit board are thereupon electrically connected together. Specifically water-tightness of the connection and the stable electric connectivity are assured by resilient force of the annular resilient member. The earth line section contributes to assuring an appropriate characteristic of the antenna.
In the present portable radio of the present invention, a reactance element is interposed between the ground section and the second electrical connection section.
In the portable radio, an electric characteristic of the earth line section can be appropriately controlled by the reactance element.
The present invention makes it possible to assure water-tightness of a neighborhood of power feed sections readily and also assure readily a stable state of connection between a conductor, such as an antenna, and a circuit board.
A portable radio of an embodiment of the present invention will be described hereunder b reference to the drawings.
An enclosure 10 of the portable radio assumes an unchangeable fixed shape and is built by means of combination of a first case 11 with a second case 12 shown in
As shown in
The flexible printed board 14 is formed into an annular shape so as to be able to surround an entire outer circumference of the circuit board 17 in the embodiment. Specifically, the outer circumference and an inner circumference of the flexible printed board 14 are formed into a rectangular shape, respectively. An outline of the inner circumference of the flexible printed board 14 is made slightly larger than an outline of the outer circumference of the circuit board 17. Further, the outline of the outer circumference of the flexible printed board 14 is made slightly larger than the outline of the inner circumference of the same. Further, the outline of the outer circumference of the flexible printed board 14 is a size that makes it possible to accommodate the flexible printed board 14 in interior space of the enclosure 10.
The word “annular shape” includes a closed circular shape that makes a circle so as to surround a certain region, a shape having a rectangular outline like a frame, and the like.
As shown in
The annular resilient member 13 is a member exhibiting elasticity to primarily realize waterproof capability; for instance, a nonconductive rubber gasket. A planar shape of the annular resilient member 13 assumes an annular shape as does the flexible printed board 14. Both an inner circumference and an outer circumference of the annular resilient member 13 are formed so as to assume; for instance rectangular planar shape. The outer circumference of the annular resilient member 13 is made larger than the outer circumference of the flexible printed board 14 and into a size that enables accommodation of the annular resilient member 13 in the interior space of the enclosure 10. The flexible printed board 14 is superposed on the annular resilient member 13 in its widthwise direction and fastened by means of an adhesive, or the like. Thus, the flexible printed board 14 and the annular resilient member 13 are assembled into one.
The embodiment provides an example in which various constituent elements are formed into rectangular shapes. However, the constituent elements may also be formed into venous conceivable shapes; for instance, substantially oval shapes.
As shown in
In the embodiment shown in
As shown in
As shown in
The thickness dimension d1 of the annular waterproof section 21 of the annular resilient member 13 is determined in consideration of a dimension of space between the rib 11a and the rib 12a achieved when the first case 11 and the second case 12 remain assembled together and appropriate pressure required to assure waterproof capability,
As shown in
A ground section 24 is formed in a portion of a lower surface of the circuit board 17 shown in
In order to electrically connect the radio circuit section with the antenna section 15 on the flexible printed board 14, to this feed electric power to the antenna, the power feed section 16 is provided. The power feed section 16 is built from a first power feed section 19 and a second power feed section 20 in the embodiment shown in
The power feed plate 23 is made of conductive thin-plate-like metal, and one end of the power feed plate 23 is electrically connected to the power feed land 25. As shown in
The thickness dimension d2 of the auxiliary power feed section 22 of the annular resilient member 13 is determined in such a way that suppression force exerted on the power feed section 16 in the thickness direction becomes appropriate when the first case 11 and the second case 12 are assembled with the annular resilient member 13 and the flexible printed board 14 sandwiched therebetween as shown in
Accordingly, when the first case 11 and the second case 12 are assembled with the annular resilient member 13 and the flexible prated board 14 sandwiched therebetween as shown in
The second case 12 can also be configured by abolishing the space 12c, to thus combine the rib 12a and the rib 12b into one.
In order to maintain, by use of the annular resilient member 13, the water proof capability and a state of an appropriate electrical connection achieved by the power feed section 16, the following points are important.
If suppression force F1 exerted on the annular waterproof section 21 (force exerted on a unit area) is too great, the force will create space between the first case 11 and the second case 12 that make up the enclosure 10, which may contrarily deteriorate water-tightness. Accordingly, the annular waterproof section 21 must be pressed by means of appropriate force that makes it possible to maintain required waterproof capability but will not make space.
Force F2 exerted to press the auxiliary power feed section 22. (force exerted on a unit area) must be designed in such a way that force F3 (force exerted on a unit area) required to sustain a state of an appropriate electrical connection is exerted on an electrical contact point between the first power feed section 19 and the second power feed section 20. A relationship between the force F2 for suppression and the force F3 exerted on the electrical contact point is determined according to an area of the electrical contact point.
When waterproof capability commensurate with a depth of; for instance, about one meter, is actually imparted to the portable radio, the force F3 exerted on the electrical contact point must be increased to 10 to 100 times as lame as the force F1 for pressing the annular waterproof section 21. A method, such as that provided below, is conceivable to share one annular resilient member 13 between the annular waterproof section 21 and the auxiliary power feed section 22 and exert appropriate suppression force on respective areas.
(1) A stroke is regulated in such a way that the suppression forces become variable, by means of changing the thickness of the annular waterproof section 21 and the auxiliary power feed section 22.
(2) Heights of protrusions of the ribs 11a, 12a, and 12b are regulated in such a way that suppression forces generated by the protrusions become variable.
As show, in
As with the flexible printed board 14, a flexible printed board 14B shown in
As with the foregoing annular resilient member 13, an annular resilient member 13B shown in
An electrode is formed on a lower surface of the extension 15Ba of the antenna section 15B, which makes up the first power feed section 19. in the meantime, an exposed electrode (a land) on the circuit board 17 is attached in such a way that a power feed pin 26 made of a conductor protrudes out of the surface of the circuit board 17 in the thickness direction. The power feed pin 26 makes up the second power feed section 20.
Therefore, when the respective constituent elements are assembled as shown in
As shown in
In the case of the configuration shown in
In the configuration shown in
As with the flexible printed board 14, a flexible printed board 14C shown in
As with the first modification, a lower end of the antenna section 15B on the flexible printed board 14C stretches along the bridging section 40, extending up to at least the power feed section 16B (a position where the antenna section opposes a portion of the circuit board 17).
An annular resilient member 13B shown in
The position where the power feed section 16B is to be placed can also be changed as necessary. For instance, supplying power feed sections in a vicinity of the center of the bridging section 40 is also conceivable. In the case of the configuration shown in
Incidentally, the preceding descriptions are based on the assumption of one enclosure. However, many portable radios have a plurality of enclosures and perform opening and closing by means of folding or sliding operation. When the portable radio has a plurality of enclosures, the portable radio is built as a result of; for instance, an upper enclosure end a lower enclosure being joined by way of a hinge, or the like. Such a portable radio is also envisaged to assume the following configuration, in which the circuit board 17 equipped with an electric circuit section, such as a radio circuit, and the annular resilient member 13 are accommodated in either the upper enclosure or the lower enclosure; and in which the flexible printed board 14 including the antenna section 15 and the annular resilient member 13 are accommodated in the other enclosure.
Explanations have been given thus tar to the case where the member that is an integrated combination of the annular resilient member 13 with the flexible printed board 14 is utilized to accomplish an electrical connection of the power feed section of the antenna section 15. A structure analogous to the structure can also be applied to an electrical connection of an earth line. The earth line is a component used for electrically forming an element corresponding to ground surface utilized by an antenna. The earth line is connected to the ground section 24 on the circuit board 17.
Although the flexible printed board 14 is not shown in
The electrical connection section 29 shown in
Accordingly, the member that is a combination of the annular resilient member 13 with the flexible printed board 14 is used even in the vicinity of the electrical connection section 29 for connecting the earth line section 27 for antenna use to the circuit board 17. Thus, stable electrical connection performance can be acquired without impairing water-tightness.
The antenna section 31 is an antenna section that can make up an inverted F antenna and assumes a strip-shaped shape that extends in the Y-axis direction. An electrode for power feeding purpose laid on the antenna section 31 is electrically connected to the electrode on the circuit board 17 by way of a power feed section 34 and connected to the radio circuit, or the like, on the circuit board 17. The ground electrode laid on the antenna section 31 shown in
The antenna section 32 assumes a trio-shape shape extending in the Y-axis direction, The power feed electrode laid in the antenna section 32 is electrically connected to the electrode on the circuit board 17 by way of a power feed section 37 and connected to the radio circuit, or the like, on the circuit board 17.
The earth line section 33 has a strip-shaped geometry extending in the X-axis direction orthogonal to the direction in which the antenna section 32 extends. The ground electrode laid in the earth line section 33 is electrically connected to the electrode on the circuit board 17 by way of an electrical connection section 38 and electrically connected further to the ground section 24 by way of a reactance element 39, as required.
The power feed section 34, the electrical connection section 35, the power feed section 37, and the electrical connection section 38 shown in
As mentioned above, various types of antennas can be built by use of the antenna section and the ground line section while assuring water-tightness of the neighborhood of the power feed sections and the electrical connection sections and assuring stable states of a connection between the conductor, such as the antenna, with the circuit board are facilitated.
Although the present invention has been described in detail by reference to the specific embodiment, it is manifest to those skilled in the art that the present invention be susceptible to various modifications and alterations without departing the spirit and scope of the invention.
The present patent application issued on Japanese Patent Application JP-2009-167999 filed on Jul. 16, 2009, the entire subject matter of which is incorporated herein by reference.
The present invention is useful for a portable radio that facilitates assuring water-tightness of a neighborhood of power feed sections and is capable of assuring easily a stable state of connection between a conductor, such as an antenna, and a circuit board.
Number | Date | Country | Kind |
---|---|---|---|
2009-167999 | Jul 2009 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2010/001477 | 3/3/2010 | WO | 00 | 1/11/2012 |