JP2009124220A - Grounding structure of tuner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grounding structure of a tuner, which can be an excellent countermeasure against beat by utilizing a metallic housing of the tuner to be able to form a grounding electric path without adding unnecessary components and eliminating risk of poor contact of the grounding electric path. <P>SOLUTION: A grounding electric path E is formed by a conductive contact piece 61 formed by bending part of a housing 60 of a tuner 20. A planar grounding electrode of a wiring substrate 80 or a device enclosure made of a sheet metal can be selected as a conductor. A contact piece 63 which can be fitted by a screw may be formed on the contact piece 61. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a grounding structure for a tuner, and more particularly to a grounding structure for a tuner in which a metal outer casing and a conductor of a tuner are connected by a grounding electrical path.

  In electrical and electronic equipment as a multifunction machine in which a common power supply board is used for a DVD drive and a video deck, and both of them are housed in a common equipment housing such as an AV board, a tuner ( Connecting a digital tuner or the like to a ground electrode such as the power supply board or AV board or a sheet metal device housing via a grounding electric circuit has been conventionally performed as a so-called beat countermeasure. A countermeasure similar to this is also taken for a receiving apparatus such as a digital television receiver.

On the other hand, regarding a liquid crystal television, it has been proposed to use a leaf spring to form a grounding electric circuit that electrically connects a digital television tuner and a jack grounding substrate (for example, see Patent Document 1).
JP 2007-67480 A

  However, in electrical and electronic equipment, if a leaf spring is separately used as in the above-mentioned Patent Document 1 as a grounding electrical circuit that electrically connects the ground electrode of the power supply board or AV board or the equipment housing and the tuner, An extra spring is required, which not only increases the parts cost and assembly cost, but also may cause a contact failure at the contact point between the contact piece at one end of the leaf spring and the outer casing of the tuner.

  The present invention has been made in view of the above situation, and when the tuner has a metal outer casing, by utilizing the outer casing, the grounding electric circuit can be provided without adding extra parts. Another object of the present invention is to provide a tuner grounding structure that can be formed and that can be an excellent countermeasure against beats by eliminating the possibility of contact failure of the grounding circuit.

  The tuner grounding structure according to the present invention is a tuner grounding structure in which a metal outer casing of a tuner and a conductor are connected by a grounding electrical circuit, and the grounding electrical circuit is a part of the outer casing of the tuner. It is formed by cutting and raising. With this configuration, a part of the tuner's metal outer casing is used as a grounding circuit without using extra leaf springs, so that a grounding circuit can be formed without adding extra parts. At the same time, there is no possibility of poor contact between the outer casing of the tuner and the grounding circuit.

  In the present invention, a configuration in which the conductor is a planar ground electrode of the wiring board is employed, or a configuration in which the conductor is a sheet metal device housing that houses the tuner is employed. It is also possible.

  In the present invention, it is desirable that the contact piece extends from the outer casing in a cantilevered manner, and has a contact piece that is pressed against the ground electrode of the wiring board by a screw. With this configuration, a part of the outer casing of the tuner is cut and raised to extend in a cantilever shape, and the contact piece at the tip of the contact piece is pressed against the ground electrode of the wiring board by screwing. In addition, there is an advantage that contact failure is less likely to occur with respect to the grounding electric circuit both to the outer casing of the tuner and to the ground electrode of the wiring board.

  In the present invention, the outer casing of the tuner is formed in a rectangular box shape, and a piece-forming piece portion is defined by a cut at a plurality of locations of the outer case. It is possible to adopt a configuration in which one is bent into a form protruding from the outer casing and used as the contact piece. When this configuration is adopted, the contact piece forming piece portion located near the ground electrode or the equipment housing of the wiring board can be bent and used as the contact piece for forming the grounding electric circuit. Therefore, the length of the grounding circuit can be shortened as much as possible, and there is an advantage that it is easy to improve the performance of the grounding circuit as a countermeasure against beats. In addition, by appropriately selecting a specific piece forming piece from a plurality of pieces for forming a piece and bending it to be used as a piece of contact, it can be used as an unobstructed space for other mounting parts. It is easily possible to route the grounding circuit.

  As described above, according to the present invention, it is possible to form a grounding circuit without adding extra parts by utilizing the metal casing of the tuner, and at the same time, the grounding circuit Therefore, it is possible to eliminate the possibility of contact failure, and to provide a tuner grounding structure with reduced component costs and assembly costs at a low cost. In addition, since a piece of metal outer casing of the tuner is cut and raised to form a contact piece that is used as a grounding circuit, there is no risk of poor contact of the grounding circuit with the outer casing of the tuner, and an excellent beat It becomes possible to provide countermeasures.

  FIG. 4 is a schematic longitudinal sectional front view illustrating an electrical / electronic device as a multifunction machine described above with respect to a tuner grounding structure according to an embodiment of the present invention. In FIG. 4, 11 is a video deck, 12 is a DVD drive, 13 is a main board, 14 is a power supply board, and 15 is an AV board. Reference numeral 20 denotes a tuner. The tuner 16 is mounted on a relay board 30 in an upright position that is electrically connected to the main board 13, and both the power supply board 14 and the AV board 15 are connected by a grounding electric circuit E. Are connected to planar ground electrodes (not shown) respectively.

  FIG. 1 is a partially broken side view specifically illustrating a grounding structure of a tuner according to an embodiment of the present invention. FIG. 2 is an external perspective view of the tuner 20 shown in FIG.

  The tuner 20 shown in FIG. 1 is mounted on the relay board 30 provided in a standing posture as described above. The relay board 30 includes a connector C connected to the main board 13 shown in FIG. A mounting plate 40 is coupled to the relay substrate 30 at a right angle. The relay board 30 is provided with a required number of distributors 50 corresponding to BS digital signals and terrestrial digital signals, and these distributors 50 are connected to the terminals 21 of the tuner 20, and The signal line connector portion 51 of the distributor 50 protrudes from the opening 41 of the mounting plate 40.

  As shown in FIG. 2, the tuner 20 includes a metal outer casing 60 that is formed in a flat box shape. A conductive contact piece 61 is formed by cutting the lower plate portion of the outer casing 60 downward in an arm shape. Therefore, the contact piece 61 extends in a cantilever manner from the outer casing 60 in a form in which the base end portion 62 is continuous with the outer casing 60. Further, in the contact piece 61 of the illustrated example, a contact piece 63 projecting from the left and right sides is provided at the tip, and screw insertion holes 64 and 65 are formed at two left and right positions of the contact piece 63. The outer casing 60 has a function as an electromagnetic shield plate by the tuner 20 or suppressing electromagnetic interference of the tuner 20.

  As shown in FIG. 1, the wiring board 80 such as the power supply board 14 and the AV board 15 described with reference to FIG. 4 is provided on the bottom plate 71 of the equipment housing that accommodates the tuner 20 and the like. A planar ground electrode (not shown) is formed in a ring shape around the screw insertion hole of the substrate 80. Then, as shown in the figure, the contact piece 63 of the contact piece 61 extending downward from the outer casing 60 of the tuner 20 is overlaid on the ground electrode of the wiring board 80, and the overlap portion is the contact piece 63. The screw insertion holes 64 and 65 and the screw insertion holes of the wiring board 80 are inserted into the screw holes 72 of the bottom plate 71 and are brought into pressure contact with each other. Accordingly, the contact piece 61 forms a grounding electric circuit E that electrically connects the outer casing 60 of the tuner 20 and the ground electrode of the wiring board 80, and the contact piece 61, the ground electrode of the wiring board 80, and the mounting screw 90 and the like form a grounding electric circuit E that electrically connects the outer casing 60 of the tuner 20 and the equipment casing. Further, the assembly operator does not need to screw extra parts such as leaf springs to the wiring board 80.

  When the grounding structure of the tuner is configured as described above, the base end portion 62 of the contact piece 61 extends in a cantilever form from the outer casing 60 in a form continuous to the outer casing 60. A situation in which the electrical circuit causes poor contact with the outer casing 60 of the tuner 20 cannot occur. Further, since the contact piece 61 is pressed against the ground electrode of the wiring board 80 by screwing the contact piece 63 at the tip thereof, a contact failure occurs even at the contact portion between the contact piece 63 and the ground electrode. Hateful. Therefore, the grounding structure of the tuner of this embodiment can be an excellent countermeasure against beats.

  In the example shown in FIG. 1, the lower plate portion of the outer casing 60 of the tuner 20 is a portion closest to the ground electrode of the wiring board 80 disposed on the lower side of the tuner 20. A conductive contact piece 61 is formed by raising and lowering the lower plate portion of the outer casing 60 of the tuner 20 downward in an arm shape. For this reason, the length of the grounding circuit formed by the contact piece 61 is as short as possible, which helps to improve the performance of the grounding circuit as a countermeasure against beats.

  FIG. 3 is an external perspective view illustrating a tuner 20 according to a modification. The tuner 20 selects a plurality of locations of the outer casing 60 formed in a flat rectangular box shape, and makes cuts 66 at the respective locations, thereby partitioning the piece-forming piece 67 by the cuts 66. It is formed. According to the tuner 20 having this configuration, it is used as a contact piece for forming a grounding electric circuit by bending one of the plurality of contact piece forming piece portions 67 into a form protruding from the outer casing 60. Is possible. Accordingly, when such a tuner 20 is mounted on a relay board or the like, the contact-forming piece 67 located near the ground electrode of the wiring board or the device casing is bent to form a grounding circuit. Can be used as the contact piece. Therefore, the length of the grounding circuit can be shortened as much as possible, and there is the same advantage as above that it is easy to improve the performance of the grounding circuit as a countermeasure against beats. It is possible to easily route the grounding circuit to a space where it is not obstructed by other mounting parts by appropriately selecting a specific one from the forming pieces 67 and bending it to use as a contact piece. There is also an advantage of becoming. Furthermore, it is also possible to form a grounding electric circuit by bending a specific piece-forming piece 67 and making it directly elastically contact with a sheet metal device housing.

  The wiring board 80 shown in FIG. 1 may be the power supply board 14 or the AV board 15 shown in FIG. As shown in FIG. 2, in the case where the screw insertion holes 64 and 65 are opened at two locations of the contact piece 63 of the contact piece 61, the power supply board 14 and the AV board arranged side by side as shown in FIG. It is also possible to place the contact piece 63 across 15 and screw it with two mounting screws 90 to press-contact the grounding electrodes of the power supply board 14 and the AV board 15 respectively. .

1 is a partially broken side view illustrating a grounding structure of a tuner according to an embodiment of the invention. FIG. 2 is an external perspective view of a tuner illustrated in FIG. 1. It is an external appearance perspective view of the tuner by a modification. 1 is a schematic longitudinal sectional front view showing a grounding structure of a tuner of a multifunction machine.

Explanation of symbols

20 tuner 60 tuner outer casing 61 contact piece 63 contact piece 66 notch 67 piece for contact piece formation 80 wiring board E grounding circuit

Claims (5)

In the tuner grounding structure in which the metal outer casing of the tuner and the conductor are connected by a grounding circuit,
A grounding structure for a tuner, wherein the grounding electric circuit is a conductive contact piece formed by cutting and raising a part of the outer casing of the tuner.   2. The tuner grounding structure according to claim 1, wherein the conductor is a planar ground electrode of a wiring board.   The tuner grounding structure according to claim 1, wherein the conductor is a sheet metal device housing accommodating the tuner.   3. The tuner according to claim 2, wherein the contact piece extends from the outer casing in a cantilevered manner, and includes a contact piece that is press-contacted to a ground electrode of the wiring board by a screw. Grounding structure.   The outer casing of the tuner is formed in a rectangular box shape, and a piece for forming a piece of contact is defined by a notch at a plurality of locations of the outer case, and one of the pieces for forming the piece of contact is formed by the outer portion. 5. The tuner grounding structure according to claim 1, wherein the tuner grounding structure is bent into a form protruding from a casing and used as the contact piece. 6.

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