JP2004273721A - High-frequency unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-frequency unit that is superior in shielding property against electromagnetic wave noise and impact resistance by shortening a time necessary for adjusting electronic components such as a coil, a variable resistor, etc. and reducing the number of parts constituting a shield case. <P>SOLUTION: A coil 15 and a variable resistor 19 as an electronic component requiring adjustment of frequency are mounted on the surface 11A of a printed board 11, and a chip 16 as an unadjustable electronic component is mounted on the rear surface 11B thereof, thereby forming the high-frequency unit. A shield case body 22 fixes the high-frequency unit 10 in a manner to cover the rear surface 11B of the printed board 11, and a case cover 21 is attached to the shield case body 22 in a manner to cover the surface 11A of the printed board 11. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a high-frequency unit, and more particularly to a high-frequency unit including a printed board on which electronic components are mounted and a shield case.
[0002]
[Prior art]
An electronic component is mounted on a printed circuit board in a high-frequency unit used for an electronic tuner for a TV or a VTR. Since the high-frequency unit is housed in the shield case, the effect of electromagnetic wave noise from outside the shield case and electromagnetic wave noise generated inside is suppressed, and mechanical protection is achieved.
[0003]
FIG. 4 is an exploded perspective view showing a conventional tuner device. As shown in FIG. 4, the tuner device 40 generally includes the high-frequency unit 30, a lower cover 41, an upper cover 42, and a shield case frame 43.
[0004]
The high-frequency unit 30 generally includes a printed circuit board 31, a coil 35, a chip component 36, a variable resistance component 38, and a connection pin 39. The coil 35 and the variable resistance component 38 are electronic components to be adjusted when adjusting characteristics such as frequency in an adjustment process for assembling the high-frequency unit 30.
The chip component 36 is an electronic component that cannot be adjusted. On the surface 31A of the printed board 31, a coil 35 and a variable resistance component 38, which are electronic components that need to be adjusted, a chip component 36, which is an electronic component that cannot be adjusted, a connection pin 39, and a ground pattern 46 are provided. Is formed. On the surface 31B of the printed board 31, a chip component 36 which is an electronic component that cannot be adjusted is formed. The connection pins 39 are for mounting the high-frequency unit 30 on another printed circuit board or the like.
[0005]
The shield case is composed of three parts including a lower cover 41, an upper cover 42, and a shield case frame 43. The lower cover 41 is formed with an opening 45 for passing the connection pin 39 to the outside and an insertion hole 44 through which the ground terminal 47 is inserted. The shield case frame 43 has a ground terminal 47 and an opening 49 through which the connection pin 39 passes.
[0006]
After being fixed to the shield case frame 43 by soldering, the high-frequency unit 30 adjusts the coils 35 and the variable resistance components 38 mounted on both sides of the printed circuit board 31. After the adjustment is completed, the lower cover 41 and the upper cover 42 are attached to the shield case frame 43, and the tuner device 40 is completed (for example, see Patent Document 1).
[0007]
The lower surface cover 41 and the upper surface cover 42 can be attached with one touch by pressing the shield case frame 43, and can be easily removed. Thereby, the frequency and the like of the coil 35 and the variable resistance component 38 can be adjusted as needed.
[0008]
FIG. 5 shows a cross-sectional view when the tuner device is mounted on a printed circuit board. As shown in FIG. 5, the tuner device 40 in which the shield case is mounted on the high-frequency unit 30 is used in a state where the tuner device 40 is mounted on the printed circuit board 50 by the connection pins 39.
[0009]
[Patent Document 1]
JP 2000-277969 A
[Problems to be solved by the invention]
Meanwhile, in the conventional high-frequency unit 30, the coil 35 and the variable resistance component 38 are mounted on both sides of the printed board 31, and it is necessary to make adjustments to the coil 35 and the variable resistance component 38 on both sides of the printed board 31. There was a problem that adjustment took time. Further, in order to adjust the coil 35 and the variable resistance component 38 mounted on both sides of the printed board 31, it is necessary to form removable covers on both sides of the printed board. Therefore, the shield case is composed of three parts, the lower cover 41, the upper cover 42, and the shield case frame 43, and three dies are required to create the three parts. There was a problem that the required cost was high.
[0011]
Further, since the number of components forming the shield case is three, there are two mounting portions between the shield case frame 43 and the upper and lower covers 41, 42. When an impact is applied, bending occurs between the shield case frame 43 and the upper and lower covers 41, 42, and the shielding performance against electromagnetic noise generated inside and outside the shield case is deteriorated. Therefore, there is a problem that the high frequency unit 30 is damaged.
[0012]
Therefore, the present invention has been made in view of the above problems, and reduces the time required for adjusting electronic components such as coils and variable resistance components that need to be adjusted, and reduces the number of components constituting a shield case. It is another object of the present invention to provide a high-frequency unit having excellent shielding properties and impact resistance against electromagnetic wave noise.
[0013]
[Means for Solving the Problems]
According to the present invention, in the high frequency unit in which an electronic component is mounted on the first and second surfaces of a printed circuit board, the electronic component can be adjusted among the electronic components. When adjusting the characteristics of the high-frequency unit, the high-frequency unit, characterized in that the electronic component that needs to be adjusted is mounted on one of the first surface and the second surface. Resolve.
[0014]
According to the above invention, when the characteristics of the high-frequency unit are adjusted on one surface of the printed circuit board, an electronic component that needs to be adjusted is formed. Just do it. Therefore, the adjustment of the electronic components can be performed in a shorter time as compared with the case where the adjustment of the electronic components requiring the adjustment is performed on both sides of the printed board.
[0015]
According to a second aspect of the present invention, there is provided a high frequency unit according to the first aspect, wherein a connection pin is formed on a surface on which the electronic component requiring the adjustment is mounted.
[0016]
According to the above invention, since the connection pin is formed on the surface on which the electronic component requiring adjustment is mounted, the connection pin can be repaired when a failure occurs in the connection pin.
[0017]
According to a third aspect of the invention, there is provided a high-frequency unit in which an electronic component is mounted on the first and second surfaces of the printed board, and the printed board on which the electronic component is mounted is housed in a shield case. The one of the first surface and the second surface can be adjusted among the electronic components, and when the characteristics of the high-frequency unit are adjusted, the adjustment is required. An electronic component is mounted, the shield case includes a case main body including a frame portion and a bottom plate portion, and a case cover covering the case main body, and the case main body is an electronic component requiring the adjustment. The printed circuit board is housed so as to expose the surface on which the electronic component is mounted, and the case cover is configured to cover the surface on which the electronic component requiring the adjustment is mounted. The high frequency unit and resolve.
[0018]
According to the above invention, the shield case is composed of two parts, the case body and the case cover. When adjusting the characteristics of the high-frequency unit, the case body has a surface on which the electronic components that need to be adjusted are mounted. The printed circuit board is stored so as to be exposed, and the case cover is configured to cover the surface on which the electronic component requiring adjustment is mounted. Therefore, when adjusting the characteristics of the high-frequency unit, it is possible to remove the case cover and adjust the electronic components that need to be adjusted. Also, since the shield case is composed of two parts, the frame part and the bottom plate part, it is more resistant to external shocks than the conventional shield case composed of three parts, The shielding performance against the generated electromagnetic wave noise can also be improved.
[0019]
In the invention according to claim 4, a connection pin is formed on a surface on which the electronic component requiring adjustment is mounted, and the connection pin is passed through the case cover to the outside of the case cover. The high frequency unit according to claim 3, wherein an opening is provided.
[0020]
According to the above invention, connection pins are formed on the surface of the printed circuit board on which the electronic component requiring adjustment is mounted, and the case cover is provided with an opening for passing the connection pins to the outside. I have. Therefore, it is not necessary to provide an opening for passing the connection pins to the outside in the case body for housing the printed circuit board, so that the strength of the case body is increased and the printed circuit board can be protected from external impact.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
[0022]
FIG. 1 is a perspective view of a tuner device according to one embodiment of the present invention. In FIG. 1, the front and back surfaces of the high-frequency unit are shown in the same drawing. The configuration of the tuner device 20 according to the embodiment of the present invention will be described with reference to FIG.
[0023]
As shown in FIG. 1, the tuner device 20 generally includes a high-frequency unit 10, a case cover 21, and a shield case main body 22.
[0024]
First, the configuration of the high-frequency unit 10 will be described. The high-frequency unit 10 generally includes a printed circuit board 11, a coil 15, a chip component 16, a connection pin 18, a variable resistance component 19, and a ground pattern.
[0025]
The surface 11A of the printed circuit board 11 is a state in which the coil 15 and the variable resistance component 19, which are electronic components that are adjusted when adjusting characteristics such as frequency, and the chip component 16, which is an electronic component that cannot be adjusted, are mixed. It is formed with. The connection pins 18, the ground pattern 25, and various patterns (not shown) are formed on the front surface 11A of the printed circuit board 11. The connection pin 18 is for connecting the tuner device 20 to another printed circuit board or the like. A chip component 16 is mounted on the back surface 11B of the printed circuit board 11.
[0026]
With such a configuration, the high-frequency unit 10 on which the coil 15 and the variable resistance component 19, which are electronic components to be adjusted when adjusting characteristics such as frequency, are mounted on the surface 11A of the printed circuit board 11. be able to. Therefore, the adjustment of the coil 15 and the variable resistance component 19 mounted on the surface 11A of the printed circuit board 11 may be performed. In comparison, the adjustment can be performed in a short time. Further, since the connection pins are formed on the front surface 11A of the printed circuit board 11, the connection pins can be repaired when a problem occurs in the connection pins.
[0027]
Next, the shield case will be described.
[0028]
The shield case generally includes a case cover 21 and a shield case main body 22. The case cover 21 has an opening 24 for passing the connection pin 18 to the outside and an insertion hole 23 for inserting a ground terminal 26 formed in the shield case main body 22. The shield case main body 22 is roughly composed of a frame portion 22B and a bottom plate portion 22C, and an earth terminal 26 is formed on the frame portion 22B.
[0029]
FIG. 2 is a sectional view of the tuner device in a state where the shield case body is soldered to the high-frequency unit.
[0030]
As shown in FIG. 2, the shield case main body 22 houses the high-frequency unit 10 so as to cover the back surface 11B of the printed circuit board 11 on which the chip components 16 are formed. At this time, the side surface portion 10C of the high-frequency unit 10 is fixed to the side surface portion 22A of the shield case main body 22 by soldering. As shown in FIG. 2, the adjustment of the coil 15 and the variable resistance component 19 mounted on the surface 11 </ b> A of the printed board 11 is performed before the case cover 24 is attached to the tuner device 20. After the adjustment of the coil 15 and the variable resistance component 19, the case cover 21 is attached to the shield case main body 22, and the tuner device 20 is completed. The case cover 21 has a configuration in which the case cover 21 can be attached with a single touch by pressing the case cover 21 on the shield case body 22 and can be easily removed. Thus, when readjustment is necessary, the case cover 21 can be easily removed, so that the adjustment of the coil 35 and the variable resistance component 38 can be performed.
[0031]
FIG. 3 shows a cross-sectional view when the tuner device is mounted on a printed circuit board.
[0032]
As shown in FIG. 3, the tuner device 20 is used by being mounted on a printed circuit board 18 by connection pins 18.
[0033]
With this configuration, the high frequency unit 10 in which the coil 15 and the variable resistance component 19 are mounted on the front surface 11A of the printed board 11 can be formed. There is no need to provide a case cover for the operation. Therefore, the shield case can be composed of the two components of the shield case main body 22 and the case cover 21, and the number of components of the shield case can be reduced from three to two. Therefore, the mold for forming the shield case may be two, that is, the mold for the case cover 21 and the mold for the shield case main body 22. In comparison, the cost required for mold production can be reduced.
[0034]
Also, even when a large impact such as a drop is applied to the shield case, the number of parts of the shield case is smaller than before, so that bending between the shield case body 22 and the case cover 21 hardly occurs, and In addition, electromagnetic wave noise generated outside can be sufficiently shielded. Furthermore, it is possible to prevent the high-frequency unit 30 inside the shield case from being damaged by impact.
[0035]
The high-frequency unit 10 shown in the present embodiment includes a coil 15 and a variable resistance component 19, which are electronic components that are adjusted when adjusting characteristics such as frequency on the surface 11A of the printed circuit board 11, and an electronic component that cannot be adjusted. Although the chip component 16 as a component is mounted in a mixed state, the same effect can be obtained by mounting only the coil 15 and the variable resistance component 19 on the front surface 11A of the printed circuit board 11.
[0036]
Although the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the specific embodiments, and various modifications may be made within the description range of the present invention described in the claims.・ Change is possible.
[0037]
【The invention's effect】
According to the present invention, among the two surfaces of the printed circuit board, an electronic component whose frequency or the like needs to be adjusted is mounted on one surface, and a high-frequency unit mounted with an electronic component that cannot be adjusted is formed on the other surface. Then, the high-frequency unit is fixed so that the shield case body covers the surface of the printed circuit board on which the unadjustable electronic components are mounted, and the case cover 21 covers the surface on which the electronic components requiring adjustment are mounted. It is configured to be mounted on the shield case body. Therefore, compared to the case where electronic components that need to be adjusted are mounted on both sides of the printed circuit board, the electronic components that need to be adjusted can be adjusted in a shorter time, and the number of components constituting the shield case can be reduced. And a high-frequency unit having excellent electromagnetic wave noise shielding and shock resistance can be realized.
[Brief description of the drawings]
FIG. 1 is a perspective view of a tuner device according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the tuner device in a state where a shield case main body is soldered to a high-frequency unit.
FIG. 3 is a cross-sectional view when the tuner device is mounted on a printed circuit board.
FIG. 4 is an exploded perspective view showing a conventional tuner device.
FIG. 5 is a sectional view when the tuner device is mounted on a printed circuit board.
[Explanation of symbols]
10, 30 High-frequency unit 11A, 31A Front surface 11B, 31B Back surface 11, 28, 31, 50 Printed circuit board 15, 35 Coil 16, 36 Chip component 18, 38 Connection pin 19, 39 Variable resistance component 20, 40 Tuner device 21 Case cover 22, 43 Shield case body 22A Side surface 22B Frame 22C Bottom plate 23, 44 Insertion hole 24, 45, 49 Opening 25, 46 Ground pattern 26, 47 Ground terminal 41 Lower cover 42 Upper cover

Claims (4)

In a high-frequency unit having electronic components mounted on first and second surfaces of a printed circuit board,
Adjustment is possible among the electronic components, and when adjusting the characteristics of the high-frequency unit, the electronic component that needs to be adjusted is placed on one of the first surface and the second surface. A high-frequency unit characterized by being mounted on a device. The high-frequency unit according to claim 1, wherein connection pins are formed on a surface on which the electronic component requiring the adjustment is mounted. An electronic component is mounted on the first and second surfaces of the printed circuit board, and the printed circuit board on which the electronic component is mounted is housed in a shield case.
Either the first surface or the second surface can be adjusted among the electronic components, and when adjusting the characteristics of the high-frequency unit, the electronic component that needs to be adjusted is adjusted. Parts are mounted,
The shield case includes a case body including a frame portion and a bottom plate portion, and a case cover that covers the case body,
The case body houses the printed circuit board so as to expose a surface on which the electronic component requiring the adjustment is mounted,
The high frequency unit, wherein the case cover is configured to cover a surface on which the electronic component requiring the adjustment is mounted. 4. The high-frequency unit according to claim 3, wherein the case cover is provided with an opening through which the connection pin passes outside the case cover. 5.

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