JPH0522167A - Card type electronic tuner - Google Patents

Abstract

PURPOSE:To obtain the external electronic tuner to enable reception while being mounted to a main body only when it is desired to receive the images and sounds of a television at an equipment such as a personal computer or an 8mm video not to normally require the tuner. CONSTITUTION:A printed circuit board 6 constituting a tuner circuit part, channel control circuit part and demodulation circuit part is built in a card type case 2, and a connector 8 to input/output signals to the printed circuit board 6 is arranged along one side of the case 2. A partition wall 44 is provided at a frame 3 constituting the case 2, and a shield plate 43 is fitted along this partition wall 44. The shield plate 43 is electrically connected to an upper cover 4, lower cover 5 and ground land on the printed circuit board 6. Therefore, the obtained card type electronic tuner can be handled similarly to a conventionally generally used IC memory card.

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 improving the form of such an electronic tuner.

[0002]

2. Description of the Related Art Television receivers require a tuner, and as such a tuner, an electronic tuner has been widely used recently. Electronic tuners often include tuner circuitry and channel control circuitry for selectively tuning both UHF and VHF signals.

Such an electronic tuner is built in the main body of the television receiver.

[0004]

As a device having an image display function which is generally used at present, in addition to the above-mentioned television receiver, for example, a personal computer having a display, such as a so-called 8 mm video device. , Information equipment, etc. As a matter of course,
Since a tuner is not built in these video equipment or information equipment, it is not possible to receive a television broadcast and output its video and audio.

However, in many cases, these video equipment and information equipment already have sufficient functions to be used as a television receiver as long as they have a tuner. Therefore, if these video equipment or information equipment can be used as a television receiver as necessary, the applications of these equipment can be expanded, and as a result, the commercial value can be increased. it can.

Therefore, the present invention seeks to meet the above-mentioned needs by improving the structure of an electronic tuner.

[0007]

In order to solve the above-mentioned technical problems, the present invention provides a card type electronic tuner.

This card type electronic tuner includes a card type case, a tuner circuit section housed in the case,
A circuit board that constitutes the channel control circuit section and the demodulation circuit section, and a connector that is electrically connected to the circuit board and that is arranged along one side of the case are provided.

The above case is a frame made of resin,
An upper cover made of a conductive material that closes the upper opening of the frame and a lower cover made of a conductive material that closes the lower opening of the frame are provided. Further, the frame is provided with a partition wall that crosses the main surface of the circuit board. A shield plate is attached along the partition wall, and the shield plate is electrically connected to the ground land on the circuit board, the upper cover and the lower cover.

[0010]

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

Further, the shield plate attached along the partition wall provided on the frame forming the case is unnecessary between the tuner circuit section, the channel control circuit section and the demodulation circuit section formed on the circuit board. Since it is connected to the ground lands on the upper and lower covers and the circuit board while blocking electromagnetic interference, it acts as a high-frequency ground and functions to maintain stable performance of the entire tuner.

[0012]

Therefore, according to the present invention, an electronic tuner of card type as a whole, 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 equipment or information equipment. Therefore, it is not necessary to store a function that is not always used in the main body of these devices, such as a function as a television receiver in a video device or an information device. It can be prevented.

Further, the card type electronic tuner according to the present invention is provided with all circuits necessary for the tuner including peripheral circuits necessary for reception, and enables signal input / output through the connector. Therefore, they can be made to function as a television receiver by mounting them on the main body of the video equipment or the information equipment when necessary. In this case, the main body of the video equipment or the information equipment is provided with, for example, a slot in which the card type electronic tuner can be mounted, and a connector paired with the connector provided in the card type electronic tuner is associated with this slot. It should be provided. If such a slot can be shared with other function cards, it becomes easy to give a plurality of optional functions to one device by switching with a switch, for example.

Further, since the shield plate having the above-mentioned function is attached along the partition wall provided on the frame constituting the case, the shield plate can be securely held and the shape or position of the partition wall can be secured. By changing it, it is easy to provide the shield plate at a desired position in a desired manner. Further, since the partition wall also reinforces the frame, as a result, the card type case is also reinforced.

[0015]

1 is a perspective view showing the appearance of a card type electronic tuner 1 according to an embodiment of the present invention. Figure 2
FIG. 2 is an enlarged sectional view taken along the line II-II in FIG. 1. Figure 3
FIG. 2 is a block diagram showing an electric circuit provided in the card type electronic tuner 1.

The card type electronic tuner 1 includes a card type case 2. Case 2 is frame 3, frame 3
And an upper cover 4 for closing the upper opening of the frame 3, and a lower cover 5 for closing the lower opening of the frame 3. Such a case 2 is preferably sized substantially the same as a general-purpose IC memory card.

The frame 3 is formed of a molded product made of a synthetic resin having an increased rigidity such as glass fiber reinforced polyphenylene sulfide, polyethylene terephthalate and polycarbonate. Such a frame 3 may be subjected to metal plating, conductive coating, or the like at a necessary portion for the purpose of improving the shield property.

The upper cover 4 and the lower cover 5 are made of a conductive material such as a metal plate in order to exhibit a shielding property.

A circuit board is housed in the case 2. The circuit board comprises a printed circuit board 6 in this example. On the printed circuit board 6, for example,
A double-sided wiring type of glass epoxy substrate having a thickness of 0.5 mm is used. Required electronic components 7 and connectors 8 are surface-mounted on the upper surface of the printed circuit board 6. The lower surface of the printed circuit board 6 is provided with required wiring and ground wiring which are electrically connected to the wiring on the upper surface through the 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, for example, ceramic, or may have a multilayer structure. Further, each outer surface of the lower cover 5 and the upper cover 4 can be appropriately used as a surface 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 along the short side of the case 2, for example.

The printed circuit board 6 on which the required electronic components 7 and the connector 8 are mounted is positioned in the case 2 mainly by the frame 3. The upper cover 4 and the lower cover 5 are fixed to the frame 3 by methods such as screwing, adhesion, and welding.

As represented by the electronic component 7 shown in FIG. 2, various circuits are formed on the printed circuit board 6. The circuit constructed on this printed circuit board 6 is shown in FIG.

Referring to FIG. 3, the circuit formed on the printed circuit board 6 is roughly divided into a tuner circuit section 9, a channel control circuit section 10 and a demodulation circuit section 11.
Further, the tuner circuit unit 9 includes the VHF circuit unit 12 and the U
The HF circuit unit 13 is provided.

U input from the 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 a bandpass filter 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 bandpass filter 21 of the UHF circuit unit 13 in the mixing circuit 25, and then amplified in the mixing / amplifying circuit 26. It 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 the amplifier 28 provided in the demodulation circuit section 11 through the bandpass 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 AM-detected and the audio signal is FM-detected to be demodulated into a video signal and an audio signal, which are applied to the video signal output terminal 31 and the audio signal output terminal 32, respectively. From the demodulation circuit 30,
A sync signal is applied to the sync signal output terminal 33.

Further, on the above-mentioned printed circuit board 6, a power supply voltage terminal 34 for supplying a power supply voltage to the entire circuit formed thereon, and the channel control circuit section 10.
A tuning voltage terminal 35 for supplying a tuning voltage to the channel control circuit section 10,
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 the corresponding contacts provided on the connector 8.

The tuner circuit section 9, the channel control circuit section 10 and the demodulation circuit section 11 described above are respectively shown in FIG.
The first area 40 and the second area 4 sectioned by the broken line in FIG.
It is arranged in the first and third regions 42. First area 40
VHF circuit section 12 included in the tuner circuit section 9
The positional relationship between the UHF circuit unit 13 and the UHF circuit unit 13 can be arbitrarily changed. In the case 2, a shield plate (described later) that separates the tuner circuit unit 9, the channel control circuit unit 10, and the demodulation circuit unit 11 from each other is arranged. Such a shield plate includes an upper cover 4 and a lower cover 5,
In addition, it is electrically connected to an earth land on the printed circuit board 6 so that the overall shield performance is ensured.

A shield plate 43, which is one of the shield plates described above, is shown in FIG. This shield plate 43 is
The frame 3 is attached along a partition wall 44 provided so as to cross the main surface of the printed circuit board 6.
The frame 3 provided with such a partition 44 is shown alone in FIG. In FIG. 4, the frame 3 is shown with the surface to which the lower cover 5 is attached facing upward.

Referring to FIG. 4, the frame 3 includes partition walls 45 and 46 in addition to the partition wall 44 described above. These partitions 44, 45, 46 provide the compartments for the aforementioned first, second and third regions 40, 41, 42. The partition walls 44 and 45 are provided with fitting protrusions 47, 48 and 49 that are received by the printed circuit board 6.

Further, the frame 3 shown in FIG. 4 shows a stepped portion 50 into which the lower cover 5 is fitted and a recessed portion 51 for positioning the connector 8.

The shield plate represented by the shield plate 43 described above is attached at the positions shown by arrows 52, 53 and 54 in FIG. 4 along the associated partition walls 44, 45 and 46, respectively. A preferred structure of such a shield plate will be described with reference to FIGS. 5 to 7 and FIGS. 8 and 9, respectively. In these drawings, the shield plate and the partition wall are generalized rather than specific ones such as the shield plate 43 and the partition walls 44 to 46 described above.

In the embodiment shown in FIGS. 5 to 7, the shield plate 55 is attached along the partition wall 56. The shield plate 55 is made of a metal plate, and as shown in FIG. 5, the shield plate 55 has a plurality of spring contact pieces 57a,
57b, 57c, 57d, 57e, ... Are formed by bending a metal plate. A temporary fixing piece 58 is formed on the shield plate 55. Spring contact pieces 57c, 57d, 57e provided along the lower side of the shield plate 55
Among them, the spring contact pieces 57c and 57e are located on the convex portions 59 and 60 on the lower side of the shield plate 55, respectively. The temporary fixing piece 58 is also located on the convex portion 60.

Such a shield plate 55 is attached along the partition wall 56, as shown in FIGS. In this attachment, first, the partition 56 is received in the temporary fixing piece 58, and the shield plate 55 is temporarily held by the partition 56. The partition plate 56 has a shield plate 55.
Fitting protrusions corresponding to the protrusions 59 and 60 are provided. 6 and 7, a fitting convex portion 61 corresponding to the convex portion 59 is shown. The printed circuit board 6 is provided with a slit 62 that receives the fitting convex portion 61 and the convex portion 59.

As shown in FIGS. 6 and 7, when the printed circuit board 6 and the upper cover 4 and the lower cover 5 are assembled in the frame, for example, the spring contact piece 57a elastically contacts the upper cover 4, The spring contact piece 57c elastically contacts the lower cover 5, and the spring contact piece 57d elastically contacts the earth land 63 on the printed circuit board 6. By these contacts, the shield plate 55 is firmly held along the partition wall 56, and the shield plate 55 is electrically connected to the upper cover 4 and the lower cover 5 and the earth land 63 on the printed circuit board 6. ..

According to this embodiment, since the shield plate 55 is attached along the partition wall 56, no separate parts, adhesives, or the like are required. Therefore, assembling work of the card type electronic tuner having such a shield plate 55 is carried out. Can be simplified.

FIG. 8 and FIG. 9 show another example of the shield plate. In this embodiment, the shield plate 64 is attached along the partition wall 65. The shield plate 64 is
A plurality of connection pieces 66a, 66b, 66c, 66d are formed by bending a part of the metal plate. The printed circuit board 6 is provided with a slit 67 that receives a part of the partition wall 65. The slit 67 also includes a part of the shield plate 64 and the connecting piece 6.
Also accepts 6b and 66d.

The shield plate 64 is electrically connected to a desired place using a conductive adhesive. That is, the contact piece 6
6a is bonded to the upper cover 4 via a conductive adhesive 68a, the connection piece 66c is bonded to the ground land 69 on the printed circuit board 6 via a conductive adhesive 68b, and the connection piece 66d is conductive. Lower cover 5 via a conductive adhesive 68c
Glued to. Similarly, the connection piece 66b is also adhered to the lower cover 5. In this way, the shield plate 64 is fixed, and the shield plate 64 is electrically connected to the upper cover 4 and the lower cover 5 and the earth land 69.

In each of the above-mentioned embodiments, the shield plate 55 or 64 extends linearly, but, for example,
A shield plate bent so as to extend integrally with the portions indicated by arrows 53 and 54 in FIG. 4 may be used.

Although not provided in the illustrated embodiment, the receiving antenna may be externally attached or built in such a card type electronic tuner.

[Brief description of drawings]

FIG. 1 is a perspective view showing an external appearance of a card type electronic tuner 1 according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line II-II in FIG.

FIG. 3 is a block diagram showing an electric circuit formed on the printed circuit board 6 shown in FIG.

FIG. 4 is a perspective view showing the frame 3 shown in FIG. 1 alone, and is shown in a posture upside down from the posture shown in FIG.

5 is a perspective view showing a shield plate 55 used as the shield plate 43 shown in FIG.

6 is a front view showing a state in which the shield plate 55 shown in FIG. 5 is attached along a partition wall 56. FIG.

7 is a cross-sectional view taken along the line VII-VII of FIG.

FIG. 8 is a top view showing a state where a shield plate 64 as another example of the shield plate is attached along a partition wall 65.

9 is a cross-sectional view taken along the line IX-IX in FIG.

[Explanation of symbols]

 1 Card Type Electronic Tuner 2 Case 6 Printed Circuit Board 7 Electronic Component 8 Connector 9 Tuner Circuit Section 10 Channel Control Circuit Section 11 Demodulation Circuit Section 12 VHF Circuit Section 13 UHF Circuit Section 43, 55, 64 Shield Plate 44, 45, 46, 56,65 Partition wall 57a-57e Spring contact piece 63,69 Earth land 66a-66d Connection piece 68a-68c Conductive adhesive

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoji Maeda 2-10-10 Tenjin 2-chome, Nagaokakyo, Kyoto Prefecture Murata Manufacturing Co., Ltd.

Claims (1)

Claim: What is claimed is: 1. A card-type case; a circuit board that houses a tuner circuit section, a channel control circuit section, and a demodulation circuit section, and that is housed in the case; Connected to, and one of the cases
And a connector arranged along one side, and the case is made of a frame made of resin, an upper cover made of a conductive material closing an upper opening of the frame, and a conductive material closing a lower opening of the frame. A lower cover is provided, a partition wall is provided on the frame so as to cross the main surface of the circuit board, a shield plate is attached along the partition wall, and the shield plate is an earth land on the circuit board and the upper part. A card type electronic tuner electrically connected to the cover and the lower cover.