JP2009141833A - Grounding structure for tuner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form an electric path for grounding, which is connected to a metallic outer case of a tuner, by using a leaf spring when connecting the electric path for grounding to the tuner in a structure for hanging-in-midair. <P>SOLUTION: The leaf spring 80 to form the electric path for grounding integrally includes: a vis-stopper 81 vis-stopped onto a lower substrate 20 as a grounding side conductor in contact with ground electrodes 23, 27 of said lower substrate 20; an elastic reed 84 extending upward from said vis-stopper 81; and a contact reed 86, provided successively to an upper end of elastic reed 84, elastically in contact with an outer case 41 of a tuner 40. The contact reed 86 adds an upward load to the tuner 40 elastically in contact with the outer case 41 of said tuner 40. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a tuner grounding structure, and more particularly to a tuner grounding structure in which a metal outer casing of a tuner is connected to a grounding conductor such as a grounding electrode of a wiring board or a device casing made of sheet metal by a grounding electric circuit. .

  A tuner (digital tuner, etc.) in an electric / electronic device as a multi-function machine in which a common power supply board is used for a DVD drive and a video deck and these are housed in a common equipment casing together with an AV board, a main board, etc. It has been conventionally performed as a so-called beat countermeasure to connect a grounding conductor such as a grounding electrode such as the power supply board or AV board or a sheet metal equipment housing through a grounding circuit.

Conventionally, in a VTR-integrated DVD player or the like, as a measure intended to reduce troubles such as noise and device failure by letting the disturbance power leaking to the tuner mounted on the main board to the top cover, It has been known that the input terminal and the upper surface cover are short-circuited by a grounding member screwed to the upper surface cover (see, for example, Patent Document 1). And in this patent document 1, it is shown that an outer surface cover and a grounding member are fastened together with a single bolt on a bracket provided on a chassis at a screwing point of the grounding member.
JP 2007-207370 A

  By the way, in the above-described multi-function device including the VTR integrated DVD player disclosed in Patent Document 1, the layout of necessary parts such as a main board, a power supply board, an AV board, and a tuner in a device casing are arranged. It may be required to incorporate the tuner in a so-called suspended structure for proper definition. The suspended structure tuner is mounted on a relay board arranged in an upright position between an upper board (for example, a main board) and a lower board (for example, a power supply board or an AV board). Then, the electric circuits of the upper board and the relay board are electrically connected to each other via a connector, and the connector is mounted on the relay board and the first connector element mounted on the upper board. It is divided into connected second connector elements. In addition, the tuner is soldered with its terminals placed sideways on the relay board.

  In such a suspended structure tuner, when a grounding circuit is connected to the outer casing, it is simply interposed between the grounding conductor of the lower substrate and the equipment casing and the outer casing of the tuner. If the grounding circuit is composed only of a leaf spring made of only a conductor, poor contact is likely to occur at the elastic contact point between the outer casing of the tuner and the leaf spring or at the elastic contact point between the ground side conductor and the leaf spring due to vibration or the like. . In addition, under the influence of the weight of the tuner of the suspended structure, the connector that connects the electrical circuits of the upper board and the relay board is disconnected, or an excessive load is applied to the soldering location of the tuner terminals. There is a risk that the soldered part will peel off.

  On the other hand, the tuner grounding structure shown in the above-mentioned Patent Document 1 is such that the input terminal of the tuner and the upper surface cover are short-circuited by a sheet metal grounding member screwed to the upper surface cover. This is not to connect the outer casing of the tuner with the structure to the ground-side conductor via a grounding circuit.

  The present invention has been made in view of the above situation. When a suspension-type tuner includes a metal outer casing, the outer casing is connected to a ground-side conductor by a grounding circuit formed by a leaf spring. Provided is a tuner grounding structure that is capable of forming a grounding circuit with excellent stability and reliability by contriving the shape of the leaf spring and the way to attach to the grounding side conductor based on the connection. For the purpose.

  In addition, the present invention is affected by the weight of the tuner having a suspended structure, and the connector that connects the electrical circuits of the upper board and the relay board is disconnected, or an unreasonable load is applied to the soldered portion of the tuner terminal. An object of the present invention is to provide a tuner grounding structure capable of avoiding the possibility that the soldered portion will be peeled off due to the addition of.

  In the tuner grounding structure according to the present invention, a relay board having a tuner mounted between an upper board and a lower board is disposed in an upright posture, and electrical circuits of the upper board and the relay board are electrically connected to each other via a connector. And the connector is divided into a first connector element mounted on the relay board and a second connector element mounted on the upper board and connected to the first connector element, and The metal outer casing of the tuner and the ground side conductor are connected by a grounding circuit. The grounding circuit is in contact with the grounding electrode of the lower substrate as the grounding side conductor and screwed to the lower substrate, and an elastic piece extending upward from the screwing piece; A conductive leaf spring that is integrally provided with a contact piece that is connected to the upper end of the elastic piece and is elastically contacted with the outer casing of the tuner by the elasticity of the elastic piece. The tuner is elastically contacted with the outer casing to apply an upward load to the tuner.

  With this configuration, the grounding circuit is not only formed by a conductive leaf spring, but the screw retaining piece provided on the leaf spring contacts the ground electrode of the lower substrate and is screwed to the lower substrate. Therefore, contact stability and contact reliability between the grounding circuit and the grounding electrode of the lower substrate as the grounding side conductor are improved. In addition, the leaf spring applies an upward load to the suspended structure tuner, so the connector that connects the electrical circuits of the upper board and the relay board is disconnected, or an excessive load is applied to the soldering location of the tuner terminals. In addition to avoiding the possibility that the soldered part is peeled off due to the addition of, the contact stability and contact reliability between the outer casing of the tuner and the contact piece of the leaf spring are improved.

  In the present invention, the ground-side conductor includes a ground electrode of the lower substrate and a sheet metal device casing electrically connected to the ground electrode, and the screw-fastening piece is screwed to the lower substrate. The mounting screw is screwed into the screw hole of the device casing through the screw insertion hole formed in the screw stopper piece and the lower substrate, so that the head of the mounting screw, the device casing, It is desirable that the screw retaining piece and the lower substrate are sandwiched between each other. According to this configuration, both the screwing piece of the leaf spring and the lower substrate forming the grounding circuit by the mounting screw are fastened together with the equipment housing as the grounding side conductor by the mounting screw common to them. Therefore, contact stability and contact reliability between the grounding circuit and the grounding electrode of the lower substrate as the grounding side conductor and the device casing are further improved.

  In the present invention, the lower substrate is divided into a power supply substrate and an AV substrate, the screwing pieces are arranged across the power supply substrate and the AV substrate, and two places of the screwing pieces are provided. It is possible to employ a configuration in which the power supply board and the AV board are screwed separately. With this configuration, the outer casing of the tuner is connected to the equipment casing as the grounding conductor via both the power supply board and the AV board via the grounding electric circuit constituted by a single leaf spring. Therefore, there is an advantage that the required number of leaf springs for connecting the outer casing of the tuner to a ground electrode of a different substrate such as a power supply substrate or an AV substrate as a grounding conductor can be reduced.

  In the present invention, the screwing piece is inserted into a slit-shaped positioning hole provided in at least one of the power supply board and the AV board, and each of the screwing piece, the power supply board, and the AV board is provided. It is desirable to have a positioning piece that positions the screw stop. With this configuration, each screwing point between the screwing piece and the power supply board and AV board is positioned by the positioning piece inserted into the positioning hole, so that the screwing work can be performed accurately and quickly. In addition, the screw fixing work does not co-rotate with the mounting screw in the screw fixing operation, and the screw fixing operation can be easily performed.

  In the present invention, it is desirable that the contact piece is elastically contacted with a lower corner portion provided in the outer casing of the tuner and an upward load is applied to the tuner. Even in this configuration, as described above, since the tuner of the suspended structure is elastically supported from below by the leaf spring, the connector connecting the electric circuits of the upper board and the relay board is detached, In addition to avoiding the possibility of an excessive load being applied to the soldered portion of the tuner terminal and peeling off the soldered portion, contact stability and contact between the tuner outer casing and the leaf spring contact piece are avoided. Reliability is also improved.

  The present invention employs a configuration in which the contact piece has a bent portion bent in a valley shape and is elastically contacted with the lower corner portion of the outer casing of the tuner at two positions on both sides of the bent portion. Is possible. According to this, since the contact piece elastically contacts the outer casing of the tuner at at least two locations, the contact stability and the contact reliability between the outer casing of the tuner and the contact piece of the leaf spring are further improved.

  As described above, according to the present invention, when a tuner with a suspended structure connects a metal outer casing to a ground-side conductor with a grounding circuit formed by a leaf spring, grounding with excellent stability and reliability is achieved. An electric circuit is formed, and a preferable countermeasure against beats can be provided. In addition, under the influence of the weight of the tuner of the suspended structure, the connector that connects the electrical circuits of the upper board and the relay board is disconnected, or an excessive load is applied to the soldering location of the tuner terminals. Since the possibility that the soldered portion is peeled off is avoided, it is possible to provide a tuner grounding structure with excellent vibration resistance.

  FIG. 1 is a longitudinal front view schematically illustrating a tuner grounding structure in a multifunction peripheral according to an embodiment of the present invention, FIG. 2 is a longitudinal side view of an enlarged main part of the grounding structure, and FIG. It is the longitudinal cross-sectional view which expanded and showed the part in the cross section.

  In the multi-function apparatus shown in FIG. 1, the video deck 100 and the DVD drive 200 arranged side by side are accommodated in a device casing 300 made of sheet metal common to them. In the device housing 300, the upper substrate 10 and the lower substrate 20 are arranged with a space therebetween. In the illustrated multifunction machine, a main board, a power supply board, and an AV board are employed as wiring boards, and the main board corresponds to the upper board 10 described above, whereas the lower board 20 is arranged side by side. The power supply board 21 and the AV board 25 are arranged. Further, the power supply substrate 21 and the AV substrate 25 as the lower substrate 20 are arranged on the bottom plate 310 of the device casing 300.

  Further, the tuner 40 is mounted on the relay board 30. The relay board 30 is arranged in a standing posture between the main board as the upper board 10 and the power board 21 as the lower board 20 by using the space between the video deck 100 and the DVD drive 200. . Further, the electrical circuits of the upper substrate 10 and the relay substrate 30 are electrically connected via the connector 50. Thus, by adopting a layout in which the relay board 30 on which the tuner 40 is mounted is arranged in a standing posture using the space between the video deck 100 and the DVD drive 200, the height of the device housing 300 is kept low. It becomes possible.

  As shown in FIG. 2, the connector 50 is divided into a first connector element 51 mounted on the end of the upper substrate 10 and a second connector element 55 mounted on the upper end of the relay substrate 30. The first connector element 51 is inserted and connected to the second connector element 55 from above. Further, the tuner 40 is inserted into the hole of the relay board 30 in the lateral direction and soldered to the land on the back surface of the relay board 30, and the signal line connector of the distributor 60 connected to the tuner 40. The portion 61 protrudes from the opening 71 of the mounting plate 70 that is coupled to the relay substrate 30 at a right angle. Under this configuration, the tuner 40, which is a relatively heavy component, has a suspended structure, and due to the weight of the tuner 40, a downward load is applied to the soldered portion between the lateral terminal of the tuner 40 and the relay substrate 30, the connector 50, and the like. Is loaded.

  In this embodiment, ground electrodes formed on the power supply substrate 21 and the AV substrate 25 as the lower substrate 20 are used as counterpart ground-side conductors to which the metal outer casing 41 of the tuner 40 is connected by a grounding electrical circuit (see FIG. 1 to 3) and a sheet metal device housing 300 are selected. The grounding circuit is formed by a conductive leaf spring 80. Hereinafter, these will be described in detail.

  4 is an exploded perspective view showing the leaf spring 80, the power supply board 21 and the AV board 25 as the lower board 20, and the bottom plate 310 made of sheet metal of the equipment housing, and FIG. 5 is a schematic perspective view of the tuner 40. 6 is a perspective view of the leaf spring 80.

  As shown in FIG. 6, the leaf spring 80 has a flat screw stopper piece 81 having screw insertion holes 82 and 83 at two locations, and a bent portion 85 bent at a substantially right angle from the screw stopper piece 81. The elastic piece 84 that extends is integrally formed with a contact piece 86 that is connected to the upper end of the elastic piece via a bent portion 87 that is bent at a substantially right angle. The contact piece 86 has a bent portion 88 bent in a valley shape and is divided into two. Further, in the leaf spring 80 of FIG. 6, the positioning pieces 91 and 92 are projected at two locations of the screw-fastening piece 81, and these protruding pieces 91 and 92 can be bent at right angles and used for use. It can be done.

  On the other hand, the tuner 40 shown in FIG. 5 includes a metal outer casing 41 in addition to the signal line connector portion 61 as described above with reference to FIG. The outer casing 41 performs an electromagnetic shielding function. Therefore, the tuner 40 is grounded by connecting a grounding electrical circuit to the outer casing 41.

  As shown in FIG. 4, the power supply substrate 21 as the lower substrate 20 includes a screw insertion hole 22 and a ground electrode 23 formed in a ring shape around the screw insertion hole 22. A screw insertion hole 22 is formed as a through hole, and has an electrode (not shown) electrically connected to the ground electrode 23 on the back side. Similarly, the AV substrate 25 as the lower substrate 20 has a screw insertion hole 26 and a ground electrode 27 formed in a ring shape around the screw insertion hole 26, and the screw insertion hole 26 is a through hole. And an electrode (not shown) electrically connected to the ground electrode 27 is formed on the back surface side. In addition, slit-shaped positioning holes 24 and 27 are formed in the power supply substrate 21 and the AV substrate 25 adjacent to the screw insertion holes 22 and 26.

  Further, as shown in FIG. 4, the bottom plate 310 of the device housing is provided with a bulging portion 312 that bulges upward, and screw holes 313 and 314 are opened at two locations at the top of the bulging portion 312. The screw holes 313 and 314 are threaded by screwing mounting screws (not shown in FIG. 4).

  Next, the assembly process will be described.

  As can be seen from FIG. 4, in the assembly process, the power supply substrate 21 and the AV substrate 25 as the lower substrate 20 are placed on the bulging portion 312 of the bottom plate 310 of the device casing. And the screw stop piece 81 of the leaf | plate spring 80 is piled up in the form straddling both those power supply boards 21 and AV board | substrates 25, and by doing so, the screw insertion holes 22 and 26 of the power supply board | substrate 21 and AV board | substrate 25 are made. The screw holes 313 and 314 of the bottom plate 310 are aligned with each other, and the screw insertion holes 82 and 83 of the screw stopper piece 81 are aligned with the screw insertion holes 22 and 26 of the power supply substrate 21 and the AV substrate 25, respectively. In this case, if necessary, the positioning pieces 91 and 92 of the screwing piece 81 are bent downward at a right angle and inserted into the positioning holes 24 and 28 of the power supply board 21 and the AV board 25. If it does in this way, each screw stop location of screw stop piece 81, power supply board 21, and AV board 25 will be positioned correctly, and positioning workability before screw stop will be improved. In addition, although positioning can be performed only by using at least one of the two positioning pieces 91 and 92, a more accurate positioning state can be obtained by using both of the positioning pieces 91 and 92. .

  After positioning the screw fixing portions of the screw fixing piece 81 and the power supply substrate 21 and the AV substrate 25 as described above, the screw fixing piece 81, the power supply substrate 21 and the AV substrate 25, and the screw insertion holes 82 and 23, 2 and 3, the mounting screws 95 and 96 are screwed into the screw holes 313 and 314 of the bottom plate 310 as shown in FIG. Then, the screwing piece 81, the power supply substrate 21 and the AV substrate 25 are clamped between the heads of the mounting screws 95 and 96 and the bottom plate 310. In this state, the screwing pieces 81 arranged across the power supply board 21 and the AV board 25 are screwed to the power supply board 21 and the AV board 25 at two locations at the same time. The screw fixing piece 81 is securely electrically connected to the bottom plate 310 via the ground electrodes 23 and 27 of the power supply substrate 21 and the AV substrate 25. At the same time, the power supply substrate 21 and the AV substrate 25 are also connected to the ground electrodes 23 and 27. 27 is securely connected to the bottom plate 310 via the connector 27.

  Next, the relay board 30 in which the tuner 41 is mounted on the power supply board 21 as the lower board 20 is arranged in a standing posture. At this time, the contact piece 86 of the leaf spring 80 is pressed against its elasticity by the lower corner portion 42 provided in the outer casing 41 of the tuner 40 as shown in FIG. 84 is bowed as shown. In this way, the pressing action by the tuner 40 and the elastic piece 84 of the leaf spring 80 are elastically pressed against each other, and an upward load is applied to the tuner 40. For this reason, the tuner 40 is elastically supported by the leaf spring 80 from below, the weight of the tuner 40 is reduced, and an excessive load is hardly applied to the soldered portion of the terminal. In addition, since the contact piece 86 of the leaf spring 80 is strongly elastically in contact with the lower corner portion 42 of the outer casing 41 of the tuner 40, contact stability between the grounding electrical path formed by the leaf spring 80 and the outer casing 41 is ensured. Is done. In particular, as shown in FIG. 2, the leaf springs are such that the two portions sandwiching the bent portion 88 of the valley-shaped contact piece 86 of the leaf spring 80 are in elastic contact with the lower corner portion 42 of the outer casing 41 of the tuner 40 in a line contact state. If the positional relationship between 80 and the tuner 40 is determined, the contact stability is further improved as described above.

  After the grounding circuit is formed by the leaf spring 80 in this way, the main board 10 shown in FIG. 2 is arranged on the relay board 30, and the first connector element 51 on the main board 10 side is connected to the second board on the relay board 30 side. The connector element 55 is inserted and connected from above. If the configuration in which the first connector element 51 is inserted and connected to the second connector element 55 from above is adopted as described above, the assemblability when the main board 10 is assembled on the upper side of the relay board 30 is improved. There is a concern that the second connector 55 may easily come out of the first connector element 52 due to the weight of the first connector element 52. However, in this embodiment, the tuner 40 is elastically supported from below by the leaf spring 80 as described above, and the weight of the tuner 40 is reduced. The situation that it is easy to come out of the one connector element 52 is improved.

  In this embodiment, the case where the lower substrate 20 is divided into the power supply substrate 21 and the AV substrate 25 has been described. However, in this respect, the lower substrate 20 may be formed by a single wiring substrate. Further, when the lower substrate 20 is divided into the power supply substrate 21 and the AV substrate 25, a grounding electric circuit formed by the leaf spring 80 is formed only between the tuner 40, the power supply substrate 21, and the device housing 300. You may keep it.

1 is a longitudinal sectional front view schematically illustrating a tuner grounding structure according to an embodiment of the present invention. It is the vertical side view which expanded the principal part of the said grounding structure. It is the longitudinal cross-sectional view which expanded and showed the III section of FIG. 1 in the cross section. It is the disassembled perspective view which showed the leaf | plate spring, the lower board | substrate, and the bottom plate of the apparatus housing | casing. It is a schematic perspective view of a tuner. It is a perspective view of a leaf | plate spring.

Explanation of symbols

10 Upper board (main board)
20 Lower substrate 21 Power supply substrate (lower substrate)
22, 26, 82, 83 Screw insertion hole 23, 27 Ground electrode (ground side conductor)
24, 28 Positioning hole 25 AV substrate (lower substrate)
DESCRIPTION OF SYMBOLS 30 Relay board 40 Tuner 41 Outer casing of tuner 42 Lower corner part of tuner 50 Connector 51 First connector element 55 Second connector element 80 Leaf spring 81 Screw retaining piece 84 Elastic piece 86 Contact piece 88 Bent portion bent into a valley shape 95, 96 Mounting screw 300 Equipment housing (ground side conductor)
313,314 Screw hole 91,92 Positioning piece

Claims (6)

A relay board with a tuner mounted between the upper board and the lower board is installed in a standing posture, and the electrical circuits of the upper board and the relay board are electrically connected to each other via a connector, and the connector is connected to the relay board. The tuner is divided into a first connector element mounted on the board and a second connector element mounted on the upper board and connected to the first connector element. In the tuner grounding structure in which the conductor is connected to the grounding circuit,
The grounding circuit is in contact with the grounding electrode of the lower substrate as the grounding side conductor and screwed to the lower substrate with a screwing piece, an elastic piece extending upward from the screwing piece, An electrically conductive leaf spring that is integrally provided with a contact piece that is connected to the upper end of the elastic piece and elastically contacts the outer casing of the tuner by the elasticity of the elastic piece. A grounding structure for a tuner, characterized in that an upward load is applied to the tuner by elastic contact with the outer casing.   The grounding conductor includes a grounding electrode of the lower substrate and a sheet metal equipment housing electrically connected to the grounding electrode, and a mounting screw for fastening the screwing piece to the lower substrate The screw fixing piece and the lower substrate are screwed into the screw holes of the equipment casing through the screw insertion holes formed between the screw fixing piece and the lower board, so that 2. The tuner grounding structure according to claim 1, wherein the screwing piece and the lower substrate are clamped.   The lower substrate is divided into a power supply substrate and an AV substrate, the screw retaining pieces are arranged across the power supply substrate and the AV substrate, and two locations of the screw retaining pieces are the power supply substrate and the AV substrate. The tuner grounding structure according to claim 2, wherein the tuner is screwed to the AV board separately.   The screwing piece is inserted into a slit-like positioning hole provided in at least one of the power supply board and the AV board, and each screwing place between the screwing piece and the power supply board and the AV board is provided. 4. The tuner grounding structure according to claim 2, further comprising a positioning piece that is positioned.   5. The tuner according to claim 1, wherein the contact piece is brought into elastic contact with a lower corner portion provided in the outer casing of the tuner and an upward load is applied to the tuner. Grounding structure.   4. The tuner grounding according to claim 3, wherein the contact piece has a bent portion bent in a valley shape and elastically contacts the lower corner portion of the outer casing of the tuner at two locations on both sides of the bent portion. Construction.

Images