JP2009009982A - Printed wiring board, electrical instrument, and discharge lamp lighting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed wiring board capable of securing working efficiency of filling synthetic resin while downsizing a substrate body. <P>SOLUTION: A surface of a via hole 35 is covered with resist R to permit synthetic resin to pass through when the resin is filled. Since the synthetic resin filled in a case body 12 passes through the via hole 35 from a rear face to a front face of the substrate body 31, it is not necessary to separately provide a hole or the like only for permitting the synthetic resin to pass, thereby securing the working efficiency in filling the synthetic resin while downsizing the substrate body 31. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printed wiring board having a substrate body on which electronic components are mounted and housed in a case body, an electric device including the printed circuit board, and a discharge lamp lighting device.

Conventionally, in a printed wiring board in which a board body mounted with electronic components is housed in a case body made of metal or the like, as a filler in the case body, in order to reduce the temperature of the electronic parts and prevent intrusion of moisture from the outside A configuration is known in which a resin body is raised and the substrate body is attached to the case body so as to spread the resin, and then the resin is thermoset (see, for example, Patent Document 1).
JP 2002-141676 A (page 3-4, FIG. 1)

  However, in the above-described electrical equipment, when the substrate body is buried in the resin, it is necessary to provide a hole for communication in order to allow the resin disposed on the back surface side of the substrate body to pass to the front surface side. There is a problem that the size of the substrate main body becomes large in order to secure the space.

  In particular, it is not easy to secure a space for providing a hole for communication in a high-density mounting board body, and if such a hole cannot be provided, the circumference of the resin deteriorates. As a result, the efficiency of the filling operation may be reduced, or an undesirable air layer may be formed.

  In addition, when the performance such as insulation of the resin to be filled is increased, the viscosity becomes high, so that it becomes more difficult to wrap around.

  The present invention has been made in view of the above points, and provides a printed wiring board that can ensure the filling work efficiency of the filling material while reducing the size of the board body, and an electric device and a discharge lamp lighting device including the printed wiring board. For the purpose.

  A printed wiring board according to claim 1 is formed in a plate shape, and a pattern is formed on each main surface, and a substrate body housed in a case body filled with a filler; mounted on the substrate body An electronic component; a plurality of via holes formed in the substrate body and electrically connecting a part of a pattern of both main surfaces of the substrate body; and the filler is filled with the via hole when filling the filler. And a covering member that covers the surface of the predetermined via hole so as to be able to pass through the predetermined via hole.

  As the case body, for example, one formed in a box shape with metal or the like is used.

  As the filler, for example, a member excellent in fluidity, heat dissipation and insulation, such as urethane or silicone resin, is used.

  The substrate body is, for example, a double-sided mounting substrate that is formed in a plate shape with an insulating resin such as glass epoxy and has electronic components mounted on both main surfaces.

  The electronic component is, for example, a capacitor, a resistor, an inductor, a transistor, or an IC, and a predetermined circuit is configured on the substrate body.

  A plurality of via holes are formed to have a hole diameter of about 0.3 to 1 mm, for example, and are configured to electrically connect patterns on both main surfaces of the substrate main body at predetermined positions by a copper foil or the like formed on the surface. ing.

  The covering member covers the copper foil or the like on the surface of a predetermined via hole where a lead wire of an electrical component is not scheduled to be inserted, so that the predetermined via hole is not blocked by solder or the like. A resist that covers a part of the surface pattern and insulates the pattern is used.

  Then, by covering the surface of the predetermined via hole with a covering member so that the filler can pass when the filler is filled, the main surface of the substrate body is filled with the filler filling the case body via the predetermined via hole. Since it passes from the side to the other main surface side, it is not necessary to separately provide a dedicated hole or the like for allowing the filler to pass therethrough, and the filling work efficiency of the filler is ensured while reducing the size of the substrate body.

  The printed wiring board according to claim 2 is the printed wiring board according to claim 1, wherein the covering members are provided on both main surfaces of the substrate body, and are formed by a resist that covers a part of the pattern on both the main surfaces. It is what.

  Then, by forming the covering member with a resist that covers a part of the pattern on both main surfaces of the substrate body, it is possible to prevent the predetermined via hole from being blocked by solder or the like during manufacturing, and the filler can prevent the predetermined via hole from being blocked. In addition to being able to pass through, a separate process or the like for covering the surface of the predetermined via hole is not required, and the manufacturability is improved.

  According to a third aspect of the present invention, there is provided an electrical apparatus comprising: the printed wiring board according to the first or second aspect; and a case body that houses the printed wiring board and is filled with a filler.

  Then, by storing the printed wiring board according to claim 1 or 2 in a case body, when the case body is filled with a filler, the filler is separated from one main surface side of the board body through a via hole. Since it passes to the main surface side, the filling work efficiency of the filler is ensured while reducing the overall size.

  The electrical device according to claim 4 is the electrical device according to claim 3, wherein the case body includes an opening facing one main surface of the substrate body, and the opening is provided in a state where the substrate body is stored in the case body. And an injection opening that is formed in communication with the portion and is capable of injecting a filler into the other main surface of the substrate main body facing the case body.

  The opening is a portion that becomes an opening when the substrate body is housed in the case body, for example.

  The injection opening has an opening area larger than each via hole, for example.

  Then, by forming an injection opening for injecting the filler material between the case body and the substrate body, it is possible to easily fill the filler material on the other main surface side of the substrate body facing the case body. In addition, the filled material passes through the via hole to one main surface side of the substrate body, so that the substrate body can be surely buried in the filler.

  According to a fifth aspect of the present invention, there is provided a discharge lamp lighting device in which the electronic component of the printed wiring board of the electric device according to the third or fourth aspect constitutes a lighting circuit component that lights the discharge lamp.

  Then, as described in claim 3 or 4, the surface of the via hole formed in the substrate body on which the lighting circuit component for lighting the discharge lamp is mounted is covered with a resist that covers a part of the pattern. It is prevented that solder is placed on the via hole and the via hole is blocked, and when the filler is filled in the state where the board body is stored in the case body, this filler is the main part of the board body through the via hole. Since it passes from the surface side to the other main surface side, the filling work efficiency of the filler is ensured while reducing the overall size.

  According to the printed wiring board of claim 1, by covering the surface of the predetermined via hole with the covering member so that the filler can pass when the filler is filled, the filler to be filled in the case body is predetermined. Since it passes from one main surface side to the other main surface side via the via hole, there is no need to provide a special hole for passing the filler, and the substrate body can be reduced in size while filling. Material filling work efficiency can be secured.

  According to the printed wiring board according to claim 2, in addition to the hardening of the printed wiring board according to claim 1, the covering member is formed by a resist that covers a part of the pattern of both main surfaces of the substrate body. Prevents a predetermined via hole from being blocked by solder or the like during manufacturing, allows the filler to pass through the predetermined via hole, and does not require a separate process for covering the surface of the predetermined via hole. Can be improved.

  According to the electrical device of the third aspect, by storing the printed wiring board according to the first or second aspect in the case body, when the case body is filled with the filler, the filler passes through the via hole. Since it passes from the one main surface side of the substrate body to the other main surface side, the filling work efficiency of the filler can be ensured while reducing the overall size.

  According to the electric device according to claim 4, in addition to the effect of the electric device according to claim 3, the case is formed by forming the injection opening for injecting the filler material between the case body and the substrate body. The other main surface side of the substrate body facing the body can be easily filled with the filler, and the filled material passes through the via hole to the one main surface side of the substrate body, thereby It can be reliably buried in the filler.

  According to the discharge lamp lighting device of the fifth aspect, as described in the third or fourth aspect, the surface of the via hole formed in the substrate main body on which the lighting circuit component for lighting the discharge lamp is mounted is provided in a pattern. By covering the part with a resist that covers the part, it prevents the via hole from being blocked due to solder or the like being placed in the via hole during manufacturing, and this filling is performed when the filler is filled with the substrate body in the case body. Since the material passes from one main surface side to the other main surface side through the via hole, the filling work efficiency of the filling material can be ensured while reducing the overall size.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  1 to 6 show an embodiment, FIG. 1 is an exploded perspective view of a discharge lamp lighting device, FIG. 2 is a longitudinal sectional view of a via hole in a substrate body of a printed wiring board of the discharge lamp lighting device, and FIG. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 3, FIG. 5 is a cross-sectional view taken along the line BB in FIG. 3, and FIG. 6 is an explanatory view of a method for manufacturing the discharge lamp lighting device.

  FIG. 1 to FIG. 5 show a discharge lamp lighting device 11 as an electric device. The discharge lamp lighting device 11 is configured by housing a printed wiring board 13 in a case body 12, and is a high-intensity discharge lamp (HID) or the like. The discharge lamp is turned on.

  The case body 12 is formed of, for example, a metal or the like, and has a rectangular bottom surface 14, side surfaces 15 and 16 that project substantially vertically upward from long sides of the bottom surface 14 facing each other, and a bottom surface 14. And end faces 17, 18 projecting substantially perpendicularly to the bottom face 14 from the mutually opposing short sides and continuing to the side faces 15, 16. The side surfaces 15 and 16 and the end surfaces 17 and 18 define a peripheral portion of a rectangular opening 19 that faces the surface that is one main surface of the printed wiring board 13. The case body 12 is filled with a synthetic resin P which is a filler in a state where the printed wiring board 13 is accommodated.

  Here, the synthetic resin P is a liquid member having fluidity, insulation and heat dissipation, such as urethane or silicone resin, and a thermosetting member.

  On the end faces 17 and 18, notches 21, 22, and 23 are formed through which unillustrated wiring connected to the printed wiring board 13 is led out.

  The opening 19 is formed in a shape larger than the printed wiring board 13 and serves as an opening for accommodating the printed wiring board 13 in the case body 12. The opening 19 can be closed by a lid 25.

  Here, the lid body 25 is provided with an insertion hole 27 in the vicinity of one long side of the top plate 26, through which the synthetic resin P can be injected into the case body 12, and the insertion hole 27 is formed of the synthetic resin P. For example, it is configured so as to be inconspicuous by being covered with a label 28 such as a nameplate after filling.

  The printed wiring board 13 includes a rectangular plate-shaped board body 31 and electronic components 32 that are lighting circuit parts mounted on the front and back surfaces of the board body 31.

  The board body 31 is a double-sided mounting board formed of an insulating member such as glass epoxy, for example. With respect to the case body 12, the surface that is one main surface is the opening 19 side, that is, the upper main surface and the other main surface. The rear surface is stored so as to be the lower side facing the bottom surface. In addition, a pattern (not shown) is formed on each of the front surface and the back surface of the substrate body 31. Of these patterns, a portion excluding a land for mounting the electronic component 32 is a covering member shown in FIG. It is covered with a certain resist R. Further, the substrate body 31 is provided with a plurality of via holes 35 for electrically connecting the patterns on the front surface and the back surface at predetermined positions. In addition, spacers 37 for forming a space 36 between the bottom surface 14 of the case body 12 and the back surface of the substrate body 31 are attached in the vicinity of the four corners of the substrate body 31. A rectangular notch 39 that forms an injection opening 38 for injecting the synthetic resin P into the space 36 between the side surface 16 of the case body 12 is cut out on one long side of the substrate body 31. It is not formed.

  The resist R is a solder resist that is formed of an insulating synthetic resin or the like and protects the pattern so that solder is not placed on the covered pattern or the like.

  As shown in FIG. 2, each via hole 35 electrically connects the hole 41 continuing from the front surface to the back surface of the substrate body 31 and the front surface and the back surface of the substrate body 31 at the inner surface of the hole 41. And a conductive portion 42 such as a copper foil. The entire surface of the conductive portion 42 is covered with a resist R. Therefore, the via hole 35 is protected by the resist R so that solder or the like is not placed thereon. The via holes 35 are portions through which the synthetic resin P filled in the space portion 36 passes from the back surface side to the front surface side of the substrate body 31, and has a hole diameter of, for example, about 0.3 to 1 mm. The number necessary for P to pass from the back surface side to the front surface side of the substrate body 31, for example, about 20 to 30 is formed so as to spread over the entire substrate body 31. In each drawing, only a part of the via hole 35 is shown for convenience and the others are omitted, and it goes without saying that the arrangement can be arbitrarily set.

  The space 36 accommodates the electronic component 32 mounted on the back surface of the substrate body 31. Therefore, the spacer 37 protrudes from the back surface of the substrate body 31 rather than the electronic component 32 mounted on the back surface of the substrate body 31, and makes contact with the bottom surface 14, thereby causing interference between the electronic component 32 and the bottom surface 14 of the case body 12. In addition, the electronic component 32 mounted on the front surface side of the board body 31 is formed so as not to protrude from the opening 19 in a state where the printed wiring board 13 is housed in the case body 12.

  The cutout 39 is cut out in a square shape in a portion of the substrate body 31 where the pattern is not formed, for example, in the central region of the long side of the substrate body 31. Further, the notch 39 is provided at a position corresponding to the insertion hole 27 of the lid body 25. Due to the notch 39, the injection opening 38 has a larger opening area than each of the via holes 35.

  Further, the electronic component 32 is, for example, a capacitor, a resistor, an inductor, a transistor, or an IC. Along with a pattern formed on the board body 31, a predetermined circuit, a lighting circuit for lighting a discharge lamp (not shown) is used. Formed on the substrate body 31.

  Further, an aluminum heat sink H is attached to the transistor 32a which is a part of the electronic component 32 by a screw 45. The aluminum heat radiating plate H is attached to the side surface 15 of the case body 12 by a screw 46 so as to be capable of conducting heat.

  Next, the operation of the above embodiment will be described.

  When assembling the discharge lamp lighting device 11, first, as shown in FIG. 6A, the board body 31 of the printed wiring board 13 in which the electronic component 32 is mounted on the case body 12 and the wiring is connected is opened to the opening 19. Insert from. At this time, the spacer 37 contacts the bottom surface 14 of the case body 12, the substrate body 31 is placed on the bottom surface 14, and a space 36 is formed between the back surface of the substrate body 31 and the bottom surface 14 of the case body 12. Is done. The substrate body 31 is fixed to the case body 12 by attaching the upper end portion of the aluminum heat radiation plate H attached to the transistor 32a with the screw 45 to the inside of the side surface 15 of the case body 12 with the screw 46 so that heat conduction is possible. .

  Next, in the state where the wiring of the printed wiring board 13 is led out from the notches 21, 22, and 23 of the case body 12, the synthetic resin P is injected from the injection opening 38 through the nozzle N as shown in FIG. Is injected into the space 36. In FIG. 6B, the synthetic resin P is injected with the lid 25 removed, but it is also possible to inject by the nozzle N via the insertion hole 27 with the lid 25 attached. .

  The injected synthetic resin P is filled in the space portion 36, and when the liquid level rises to the back surface of the substrate body 31, it passes through each via hole 35 and goes around to the surface side of the substrate body 31.

  At this time, since the hole diameter of the via hole 35 is about 0.3 mm to 1.0 mm, the flow rate of the synthetic resin P passing through one via hole 35 is small, but there are many via holes 35 protected by the resist R. Therefore, a large amount of the synthetic resin P flows as a whole, and as a result, the synthetic resin P smoothly wraps around the surface side of the substrate body 31.

  Further, synthetic resin P is injected, and as shown in FIG. 6 (c), the case body 12 is kept at a predetermined temperature as shown in FIG. 6 (d) with the electronic component 32 on the surface side of the substrate body 31 covered. The synthetic resin P is cured by performing a heat treatment for a predetermined time below, and the discharge lamp lighting device 11 is completed.

  Thereafter, by connecting the wirings derived from the notches 21, 22, and 23 to a predetermined circuit or the like, the discharge lamp is turned on by the lighting circuit in response to a signal input from the outside.

  In FIG. 6, the substrate body 31 is first fixed to the case body 12 and filled with the synthetic resin P. However, the case body 12 is filled with a predetermined amount of the synthetic resin P first, and then the substrate body 31 is attached to the case. Even if it is inserted and fixed to the body 12, the discharge lamp lighting device 11 may be assembled by such a method because the wraparound is performed by the via hole 35.

  As described above, the surface of the via hole 35 is covered with the resist R so that the synthetic resin P can pass when the synthetic resin P is filled, so that the synthetic resin P filled in the case body 12 passes through the via hole 35. The substrate body 31 passes from the back side to the front side. That is, by sharing the via hole 35 for wrapping around the synthetic resin P, the filling work efficiency of the synthetic resin P can be ensured.

  In particular, for example, in a high-density mounting printed wiring board 13 or the like, it is not easy to secure a space for separately providing a dedicated hole portion that does not perform copper plating or the like for allowing the synthetic resin P to pass therethrough. In addition, since the via hole 35 is shared for the passage of the synthetic resin P, it is not necessary to separately provide a dedicated hole or the like, and it is not necessary to provide a space for such a hole in the substrate body 31. Can be miniaturized.

  Further, the synthetic resin P may increase in viscosity when the amount of the heat radiating material contained therein is large. When the viscosity is large in this way, the injected space portion 36 moves to the surface side of the substrate body 31. Since it is difficult to wrap around the synthetic resin P, the synthetic resin P can be stably filled without forming an undesired air layer or the like in the space 36 by making the synthetic resin P wrap around through the via holes 35.

  Further, an injection opening 39 for injecting the synthetic resin P is formed between the case body 12 and the substrate body 31, so that the interior of the space 36 is moved to the back side of the substrate body 31 facing the case body 12. The synthetic resin P can be easily filled with the synthetic resin P and the synthetic resin P filled in the space portion 36 passes through the via hole 35 to the surface side of the substrate main body 31 so that the substrate main body 31 is placed in the synthetic resin P. It can be surely buried.

  In addition, by covering the surface of each via hole 35 with a resist R that covers part of the pattern on both main surfaces of the substrate body 31, the surface of each via hole 35 can be covered simultaneously when covering part of the pattern, In addition, it is possible to prevent the via hole 35 from being blocked by solder or the like at the time of manufacture, and a separate process for covering the surface of the via hole 35 is not required, so that the productivity can be improved.

  Since the synthetic resin P to be filled has an insulating property, even when the case body 12 is relatively small in size and close to the printed wiring board 13, the printed wiring board 13 and the case body 12 are not affected. Insulation can be secured.

  A printed wiring board 13 on which an electronic component 32 as a lighting circuit component such as an inverter lighting circuit for lighting a discharge lamp is mounted is accommodated in the case body 12, and the synthetic resin P is uniformly filled in the case body 12. The discharge lamp lighting device 11 can be configured, and the discharge lamp lighting device 11 can be reduced in size while ensuring the efficiency of filling the synthetic resin P while ensuring the heat dissipation and insulation of the discharge lamp lighting device 11. , Can improve the reliability.

  In each of the above embodiments, the injection opening 39 is formed between the case body 12 and the substrate body 31 by providing, for example, a spacer that separates the inner surface of the case body 12 and the peripheral portion of the substrate body 31. May be.

  Furthermore, as the covering member, any insulating member other than the resist R can be used as long as it covers the surface of the via hole 35 so that the synthetic resin P can pass through the via hole 35.

  The electrical equipment is not limited to a discharge lamp lighting device using a lighting circuit component for lighting a discharge lamp, but can also be applied to other power conversion devices, other electrical equipment, and the like. can get.

It is a disassembled perspective view of the discharge lamp lighting device which shows one embodiment of this invention. It is a longitudinal cross-sectional view of the via hole of the board | substrate body of the printed wiring board of a discharge lamp lighting device same as the above. It is a top view of a discharge lamp lighting device same as the above. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is explanatory drawing of the manufacturing method of a discharge lamp lighting device same as the above.

Explanation of symbols

11 Discharge lamp lighting device as electrical equipment
12 Case body
13 Printed circuit board
19 opening
31 Board body
32 electronic components
35 Beer Hall
38 Injection opening P Synthetic resin as filler R Resist as covering member

Claims (5)

A substrate body that is formed in a plate shape, has patterns formed on both main surfaces, and is stored in a case body filled with a filler;
Electronic components mounted on the board body;
A plurality of via holes formed in the substrate body and electrically connecting a part of the patterns on both main surfaces of the substrate body;
A covering member that covers a surface of each of the predetermined via holes so that the filler can pass through the predetermined via hole among the via holes when the filler is filled;
A printed wiring board comprising: The printed wiring board according to claim 1, wherein the covering member is formed of a resist that is provided on both main surfaces of the substrate main body and covers a part of a pattern on both the main surfaces. A printed wiring board according to claim 1 or 2;
A case body that houses the printed wiring board and is filled with a filler;
An electrical apparatus comprising: The case body includes an opening facing one main surface of the substrate body,
The case body includes an injection opening formed in communication with the opening in a state in which the substrate body is accommodated, and capable of injecting a filler into the other main surface side of the substrate body facing the case body. The electric device according to claim 3, wherein the electric device is provided. The discharge lamp lighting device, wherein the electronic component of the printed wiring board of the electrical device according to claim 3 or 4 constitutes a lighting circuit component for lighting the discharge lamp.

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