JP3094608B2 - Card type electronic tuner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic tuner, and more particularly to an improvement in the form of such an electronic tuner.

[0002]

2. Description of the Related Art A television receiver requires a tuner, and as such a tuner, an electronic tuner has recently been widely used. An electronic tuner is often provided with a tuner circuit section and a channel control circuit section for selectively tuning both UHF and VHF signals.

[0003] Such an electronic tuner is built in the main body of a television receiver.

[0004]

At present, in addition to the above-mentioned television receivers, for example, a personal computer having a display, such as a so-called 8-mm video device, is commonly used as a device having a video display function. And information equipment. As a matter of course,
Since these video and information devices do not have a built-in tuner, they cannot receive television broadcasts and output their video and audio.

[0005] However, these video and information devices often already have sufficient functions to be used as a television receiver if they have a tuner. Therefore, if these video equipment or information equipment can be used as a television receiver if necessary, the use of these equipment can be expanded, and as a result, the commercial value can be increased. it can.

Accordingly, the present invention seeks to satisfy the above-mentioned needs by improving the structure of the electronic tuner.

[0007]

According to the present invention, a card-type electronic tuner is provided to solve the above-mentioned technical problems.

This card type electronic tuner has a card type case, a tuner circuit section housed in the case,
A circuit board forming a channel control circuit section and a demodulation circuit section; and a connector electrically connected to the circuit board and arranged along one side of the case.

The above-mentioned case includes an upper cover and a lower cover made of a conductive material and opposed to each other with the circuit board interposed therebetween. Each of the upper cover and the lower cover has a side wall that stands up at a peripheral edge thereof, and is fixed to each other in a state where the side walls are overlapped.

[0010]

According to the present invention, circuits necessary for an electronic tuner, including peripheral circuits necessary for reception, are housed in a card-type case, and signals can be input / output via a connector. .

[0011]

Therefore, according to the present invention, a card-type electronic tuner such as an IC memory card can be obtained. Such a card-type electronic tuner is easy to store and carry, and is suitable for handling as an optional accessory for various video or information devices. For this reason, it is not necessary to store functions that are not always used, such as a function as a television receiver in a video device or an information device, in the main body of these devices, so that the size and weight of such devices are increased. Can be prevented.

Further, the card-type electronic tuner according to the present invention includes all necessary circuits for the tuner, including peripheral circuits required for reception, and allows signals to be input and output via a connector. Thus, when necessary, they can be made to function as a television receiver, for example, by being attached to the main body of a video device or an information device. In this case, the main body of the video device or the information device is provided with, for example, a slot in which the card-type electronic tuner can be mounted. It should be provided. If such a slot can be shared with another function card, it becomes easy to provide a plurality of optional functions to one device by, for example, switching with a switch.

Further, the upper cover and the lower cover provided in the case each have side walls rising at the peripheral edge, and the upper cover and the lower cover are fixed to each other in a state where the side walls are overlapped. Sufficient rigidity can be given to a card type case that tends to have insufficient rigidity.

The entire space in such a case is
It can be used to place various components for a circuit board and the circuits configured therein. Therefore, the limited space in the card type case can be effectively used. As a result, it is possible to easily cope with higher functions of the electronic tuner, such as taking in the peripheral functions of the electronic tuner into the card-type electronic tuner.

[0015]

FIG. 2 is a perspective view showing an appearance of a card-type electronic tuner 1 according to an embodiment of the present invention. FIG.
FIG. 2 is an exploded perspective view showing components included in such a card-type electronic tuner 1. FIGS. 3, 4 and 5 respectively show the line III of FIG. 1 in the assembled state.
FIG. 5 is an enlarged cross-sectional view taken along lines -III, IV-IV, and VV. FIG. 6 is a block diagram showing an electric circuit provided in the card-type electronic tuner 1.

The card type electronic tuner 1 has a card type case 2 as shown in FIG. Case 2 is preferably substantially the same size as a commonly used IC memory card. The case 2 includes a connector case 3, an upper cover 4, and a lower cover 5, as shown in FIG.

In such a case 2, a circuit board is housed. The circuit board comprises a printed circuit board 6 in this embodiment. On the printed circuit board 6, for example,
A double-sided wiring type made of a glass epoxy substrate having a thickness of 0.5 mm is used. On the upper surface of the printed circuit board 6, required electronic components 7 and connectors 8 are surface-mounted. On the lower surface of the printed circuit board 6, required wiring and ground wiring are provided, which are electrically connected to the wiring on the upper surface via through holes. Although not shown, the lower surface of the printed circuit board 6 is covered with an insulating film.

The printed circuit board 6 may be made of a ceramic material, for example, or may have a multilayer structure. The outer surfaces of the lower cover 5 and the upper cover 4 can be used as appropriate for printing or the like.

As described above, the connector 8 surface-mounted on the printed circuit board 6 is of a socket type, and is arranged, for example, along the short side of the case 2.

As represented by the electronic component 7 shown in FIG. 1, various circuits are formed on the printed circuit board 6. The circuit formed on the printed circuit board 6 is shown in FIG.

Referring to FIG. 6, circuits formed on printed circuit board 6 are roughly divided into a tuner circuit section 9, a channel control circuit section 10, and a demodulation circuit section 11.
Further, the tuner circuit section 9 includes a VHF circuit section 12 and a UHF circuit section.
An HF circuit unit 13 is provided.

U input from U / V signal input terminal 14
The HF / VHF signal is distributed by the distributor 15 and input to the corresponding circuit unit 12 or 13. These circuit units 12 and 13 are respectively provided with bandpass filters 16
And 17, amplifiers 18 and 19, and bandpass filters 20 and 21.

The channel control circuit section 10 includes a channel control circuit 22, and the output of the channel control circuit 22 is input to local oscillation circuits 23 and 24. The local oscillation signal output from one local oscillation circuit 24 is mixed with the high-frequency signal output from the band-pass filter 21 of the UHF circuit unit 13 in the mixing circuit 25, and then amplified in the mixing / amplification circuit 26. You. On the other hand,
The local oscillation signal output from the local oscillation circuit 23 is mixed in the mixing / amplification circuit 26 with the high-frequency signal output from the bandpass filter 20 of the VHF circuit unit 12.

The intermediate frequency signal output from the mixing / amplifying circuit 26 is input to an amplifier 28 provided in the demodulation circuit section 11 through a band pass filter 27. The signal amplified by the amplifier 28 is input to the demodulation circuit 30 via the surface acoustic wave filter 29. In the demodulation circuit 30, the video signal is subjected to AM detection and the audio signal is subjected to FM detection, whereby the video signal and the audio signal are demodulated to be supplied to the video signal output terminal 31 and the audio signal output terminal 32, respectively. Also, from the demodulation circuit 30,
The synchronization signal is supplied to the synchronization signal output terminal 33.

Further, the above-mentioned printed circuit board 6 has a power supply voltage terminal 34 for supplying a power supply voltage to the entire circuit formed thereon, and a channel control circuit section 10.
A tuning voltage terminal 35 for supplying a tuning voltage to the
A clock terminal 36 for supplying a data signal and an enable signal, a data terminal 37 and an enable terminal 35, and a ground terminal 39 are formed.

The terminals 14, 31 to 39 thus formed on the printed circuit board 6 are electrically connected to corresponding contacts provided on the connector 8, respectively.

The above-described tuner circuit section 9, channel control circuit section 10 and demodulation circuit section 11 are respectively shown in FIG.
On the printed circuit board 6 shown in FIG.
0, the second area 41 and the third area 42. The positional relationship between the VHF circuit unit 12 and the UHF circuit unit 13 included in the tuner circuit unit 9 in the first area 40 can be arbitrarily changed.

A box-shaped shield member 43 is mounted on the printed circuit board 6 so as to cover the first area 40, that is, the area where the tuner circuit section 9 is formed. The second area 41, that is, the channel control circuit unit 1
Another shield member 44 is mounted on the printed circuit board 6 so as to surround the area where the 0 is configured. These shield members 43 and 44, like the other electronic components 7,
It is fixed to the printed circuit board 6 by the solder 45. At this time, the shield members 43 and 44 are electrically connected to an earth land (not shown) on the printed circuit board 6 via the solder 45. In order to position the shield members 43 and 44 with respect to the printed circuit board 6, a slot or the like for receiving a part of each of the shield members 43 and 44 may be provided on the printed circuit board 6.

A shield member 43 covering the tuner circuit section 9
Are provided with a plurality of adjustment holes 46. Although not shown, electronic components to be adjusted are located below these adjustment holes 46. The shield member 43 is provided with a contact piece 47 projecting obliquely upward so as to exert a spring property. The contact piece 47 is connected to the card-type electronic tuner 1.
When assembled, it comes into contact with the upper cover 4 and is grounded.

The shield member 44 provided so as to surround the channel control circuit section 10 is provided with a contact piece 48 extending downward and a contact piece 49 extending diagonally upward.
Although not shown, the contact piece 48 penetrates through the earth land on the printed circuit board 6 and / or the printed circuit board 6 and contacts the lower cover 5. The contact piece 49 contacts the upper cover 4.

The above-mentioned shield members 43 and 4
The shielding function provided by 4 may be replaced by a shielding member having another shape or structure.

The connector case 3 is for positioning the connector 8 and has a shape for receiving a part of the connector 8. The connector case portion 3 has a relatively complicated structure, but has a relatively large thickness, and therefore can be manufactured by die-casting or resin molding of aluminum. The connector case 3 is provided with connecting portions 50 and 51 protruding from both ends thereof.

The upper cover 4 and the lower cover 5 are preferably made of a conductive material such as a metal plate in order to exhibit a shielding property. The upper cover 4 and the lower cover 5 have side walls 52 and 53 that stand up at the peripheral edge, respectively. Upper cover 4 and lower cover 5
Are fixed to each other in a state where the side walls 52 and 53 are overlapped. These side walls 52 and 53 are
In order not only to increase the rigidity of the upper cover 4 and the lower cover 5 but also to make the shielding effect more perfect, respectively, to mechanically fix the upper cover 4 and the lower cover 5 to other elements. It is also used as a part. Hereinafter, the above-described fixed mode will be described while explaining the method of assembling the card-type electronic tuner 1.

First, all the electronic components 7, the connectors 8,
The connector case 3 is disposed on the printed circuit board 6 on which the shield members 43 and 44 are mounted.
At this time, since the connector case portion 3 has a shape for receiving the connector 8, it is reliably positioned with respect to the connector 8.

Next, the lower cover 5 is arranged so as to contact the lower surface of the printed circuit board 6. At this time, the plurality of protrusions 54 provided at the end of the printed circuit board 6 fit into the slots 55 provided in the side wall 53 of the lower cover 5. Slot 55 may be replaced by a recess.
As shown in FIG. 5, from below the lower cover 5, a screw 56 is provided with a screw hole 57 provided in the lower cover 5 and a screw hole 58 provided in the printed circuit board 6. Through the connecting portion 50 of the connector case portion 3.
And 51 are screwed into screw holes 59 provided respectively.

The fixing by the combination of the projection 54 and the slot 55 may be changed to screwing, or conversely,
The fixing by the screw 56 may be changed to a mating fixing means such as a combination of a protrusion and a slot.

As described above, when the lower cover 5 is attached, the electronic components 7 mounted on the printed circuit board 6 are
Is adjusted to obtain predetermined electric performance as a tuner.

Finally, the upper cover 4 is put on the printed circuit board 6 and the lower cover 5. In this state, as shown in FIG. 3, screws 60 are provided from the outside in screw holes 61 provided in the side wall 52 of the upper cover 4 and in the side wall 53 of the lower cover 5. Through the screw holes 62 and screwed into screw holes 63 provided in the connecting portions 50 and 51 of the connector case 3. As shown in FIG. 4, a screw 64 is passed through a screw hole 65 provided in the side wall 52 of the upper cover 4 from the outside, and provided in the side wall 53 of the lower cover 5. It is screwed into the screw hole 66 provided.

The fixing by the screws 60 and 64
At least a part thereof may be replaced by fitting fixing means such as a combination of a projection and a recess.

As described above, the card type electronic tuner 1
Is completed. Although the receiving antenna is not provided in the illustrated embodiment, such a receiving antenna may be externally or internally provided in the card-type electronic tuner.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing elements included in a card-type electronic tuner 1 according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the appearance of the card-type electronic tuner 1 shown in FIG. 1 in an assembled state.

FIG. 3 is an enlarged cross-sectional view after assembly along a line III-III in FIG. 1;

FIG. 4 is an enlarged cross-sectional view after assembly along a line IV-IV in FIG. 1;

FIG. 5 is an enlarged sectional view after assembly along the line VV in FIG. 1;

FIG. 6 is a block diagram showing an electric circuit formed on the printed circuit board 6 shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Card-type electronic tuner 2 Case 3 Connector case part 4 Upper cover 5 Lower cover 6 Printed circuit board 7 Electronic component 8 Connector 9 Tuner circuit part 10 Channel control circuit part 11 Demodulation circuit part 12 VHF circuit part 13 UHF circuit part 52, 53 Side wall 54 Projection 55 Slot 56,60,64 Screw 57-59,61-63,65,66 Screw hole

Continuation of the front page (56) References JP-A-60-52177 (JP, A) JP-A-57-198588 (JP, A) JP-A-1-37087 (JP, U) JP-A-63-25468 (JP) , U) Actually open 2-88338 (JP, U) Actually open sho 59-84937 (JP, U) Actually open sho 61-90331 (JP, U) Really open sho 63-113334 (JP, U) Actually open 61-192499 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04B 1/08 H03J 5/00 H05K 5/02 H04N 5/64

Claims (1)

(57) [Claims] A card-type case, a circuit board housed in the case, the tuner circuit section, a channel control circuit section, and a demodulation circuit section; and a circuit board electrically connected to the circuit board; Case 1
And a connector disposed along a One side, wherein the case, facing each other across the circuit board, conductive
A card-type electronic tuner comprising an upper cover and a lower cover made of a material , wherein the upper cover and the lower cover each have side walls rising at a peripheral edge thereof, and are fixed to each other in a state where the side walls are overlapped with each other. .