JP2009105216A - Printed wiring circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed wiring circuit board capable of protecting packaging parts from an external noise voltage input via conductive parts for fixing a substrate. <P>SOLUTION: This invention relates to the printed wiring circuit board in which wiring patterns are formed on an insulating substrate 1 with printed wirings, equipped with: a first conductive pattern 3 and a second island-shaped conductive pattern 4 which are formed on the insulating substrate 1; conductive parts 2 for fixing the substrate which are furnished so as to electrically link up with the first conductive pattern 3 on the insulating substrate 1; and at least a pair of projections 3a, 4a which are formed in the first conductive pattern 3 and the second conductive pattern 4 in the shape of a protrusion, respectively, and whose respective edges mutually come very close to form a discharge gap. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printed wiring circuit board, and more particularly to a printed wiring circuit board on which a metal component for fixing a board or the like is mounted. .

  In general, when an external noise voltage such as surge voltage enters the power wiring pattern or signal wiring pattern of a printed wiring circuit board from the outside, circuit components electrically connected to the power wiring pattern or signal wiring pattern are protected from destruction. The means to do is adopted. As an example of such protection means, a minute discharge gap is formed between patterns such as a power supply wiring pattern and a signal wiring pattern, and an external noise voltage is discharged and reduced.

  For example, Patent Documents 1 and 2 disclose that a pair of power supply wiring patterns is provided with a discharge gap forming protrusion, or a grounding power supply wiring pattern and a signal wiring pattern are provided with discharge gap forming protrusions. ing.

  Patent Documents 3 and 4 disclose that a grounding power supply wiring pattern and a signal wiring pattern are provided with a protrusion for forming a discharge gap.

Patent Document 5 discloses a metal core printed wiring board in which a surge induction portion is formed continuously to a ground portion of a conductive pattern formed on a metal plate via an insulating layer.
JP 2001-135897 A Japanese Utility Model Publication No. 53-135561 Japanese Utility Model Publication No. 2-86165 JP 2000-307201 A JP 2007-129055 A

  Intrusion of external noise voltage to the printed wiring circuit board is not limited to the power supply wiring pattern and signal wiring pattern described above, and may enter via other used components. However, effective countermeasures in this case are desired. ing.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a printed circuit board that can protect a mounting component from an external noise voltage input via a substrate fixing conductive component.

  The printed wiring circuit board of the present invention is a printed wiring circuit board in which a wiring pattern is formed by printed wiring on an insulating substrate, and is formed on the insulating substrate so as to be electrically insulated from the wiring pattern. A first conductive pattern for fixing the insulating substrate; and a second conductive pattern formed adjacent to the first conductive pattern, wherein the first conductive pattern and the second conductive pattern Is characterized in that at least one protrusion is formed, and the tips of the protrusions are close to each other.

  In the above configuration, it is possible to form a discharge gap when the tips of the protrusions of the first conductive pattern and the second conductive pattern are close to each other. In this case, it is preferable to form a discharge gap of 1 mm or less.

  The second conductive pattern can be an island pattern electrically insulated from the surrounding wiring pattern, or a part of the grounding power supply wiring pattern can be used. When the second conductive pattern is formed as an island pattern, high-density component mounting in which a grounding power wiring pattern cannot be provided at an appropriate location in the vicinity of the base end portion of the metal component for fixing the substrate on the insulating substrate Even in the state, a discharge gap can be formed.

  Moreover, it is preferable that the shape of the protrusion is a triangular pattern. When the insulating substrate has a multilayer wiring structure, the first conductive pattern and the second conductive pattern may be formed in different layers in the multilayer wiring structure. This makes it possible to realize further high-density mounting.

  As an example of the first conductive pattern, a triangular protrusion is formed on each side of the concave pattern formed on one side of the square pattern toward the inside of the concave pattern, and the second conductive pattern is formed. An example of the pattern may be one triangular island pattern formed in the vicinity of the opening of the concave pattern portion of the first conductive pattern. In this case, the three triangular protrusions in the first conductive pattern and the three protrusion-shaped tips in the triangular island pattern are in close proximity to each other and face each other.

  In the example of the insulating substrate, a circuit component is mounted on the front surface side, a first conductive pattern and a second conductive pattern are formed on the back surface side, and a conductive component for fixing the substrate is mounted. An example of the conductive component for fixing the substrate is a metal surface-mounting structure in which the base end portion is fixed to the first conductive pattern by soldering and the distal end side can be fixed to, for example, a metal fixing plate. It is a spacer.

  According to the printed wiring circuit board of the present invention, for example, when assembling so as to attach a conductive component for fixing a substrate to a fixing plate in a site used on the user side, even if noise voltage such as static electricity enters from the outside, it is discharged. External noise voltage can be reduced by discharging at the gap.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this description, common parts are denoted by common reference numerals throughout the drawings.

<First Embodiment>
FIG. 1 is a perspective view schematically showing an example of a state in which a printed circuit board according to the first embodiment of the present invention is assembled to be attached to a fixed plate. 2 to 8 are perspective views showing a plurality of examples of conductive patterns for forming a discharge gap formed on one side of the printed circuit board shown in FIG.

  The printed wiring circuit board 1 has various wiring patterns (such as a power supply wiring pattern and a signal wiring pattern not shown) formed on the insulating substrate by printed wiring, and circuit components are mounted on the surface side. The insulating substrate 1 may be a substrate in which an insulating layer is formed on a metal plate or a substrate having a multilayer wiring structure.

  On the back side of the printed circuit board 1, a grounding power supply wiring pattern (not shown), the first conductive pattern 3, and the second conductive patterns 4 and 5 are simultaneously formed in the same process. When mounting the component on the printed circuit board 1, the conductive component 2 for fixing the substrate is mounted on the back side. In this case, the board-fixing conductive component 2 is attached so as to be electrically connected to the first conductive pattern 3 without being electrically connected to the second conductive patterns 4 and 5.

  The first conductive pattern 3 and the second conductive patterns 4 and 5 have protrusion-shaped patterns (protrusions) 3a, 4a, and 5a, respectively, and the tips of the protrusions are close to each other. Oppositely, at least a pair of discharge gaps is formed. Such protrusions (discharge gap forming portions) 3a, 4a, and 5a can be triangular patterns or linear patterns (not shown) that are thin enough not to peel off from the printed circuit board 1 due to heat or the like. The discharge gap is preferably changed as appropriate according to the external noise voltage, and it is preferable that the gap is as close as possible because discharge to peripheral circuit components can be prevented. In particular, it is preferable to set the distance between the discharge gaps to 0.05 mm or more and 1 mm or less because external noise such as static electricity easily discharges between the discharge gaps.

  The second conductive patterns 4 and 5 are (a) an island pattern 4 that is electrically insulated from surrounding wiring patterns and formed in an island shape, and (b) a power supply wiring pattern 5 for grounding. In some cases, (c) the island pattern 4 and a part of the grounding power supply wiring pattern 5 are used together.

  When the second conductive pattern is formed by the island-like pattern 4, a grounding power wiring pattern cannot be provided at an appropriate location near the base end portion of the board-fixing conductive component 2 on the circuit board 1. The discharge gap forming portion can be formed even in a component mounting state with a high density. In addition, it is possible to protect mounted components from external noise voltage while maintaining gaps between circuit components stipulated by various standards, gaps between components and wiring patterns, and gaps between wiring patterns at appropriate intervals. . In addition, it is not necessary to provide the discharge gap forming portion in the power supply wiring pattern as compared with the case where the second conductive pattern is formed by the power supply wiring pattern. Therefore, it is not necessary to change the shape for forming the discharge gap in the power supply wiring pattern, and there is no need to worry about unnecessary radiation increase due to the shape change.

  FIG. 2 shows an example of a pair of discharge gap forming portions 3a and 4a. Here, as the discharge gap forming portion 3 a, one triangular protrusion is formed at one corner of the rectangular first conductive pattern 3. And as the discharge gap formation part 4a, one triangular island-like pattern 4 is formed, and the corner part is used.

  FIG. 3 shows an example of three pairs of discharge gap forming portions 3a and 4a. Here, as the discharge gap forming portion 3 a, three triangular projections are formed on one side of the rectangular first conductive pattern 3. And as each discharge gap formation part 4a, each one corner | angular part in the three island-like patterns 4 each formed in the triangle shape is used.

  FIG. 4 shows another example of three pairs of discharge gap forming portions 3a and 4a. Here, as the discharge gap forming portion 3a, a triangular projection is formed on each side of the concave pattern formed on one side of the square pattern toward the inside of the concave pattern. Then, as the discharge gap forming portion 4a, three corner portions in one triangular island-shaped pattern 4 formed near the opening of the concave pattern portion of the first conductive pattern 3 are used. . In this case, the three triangular protrusions of the first conductive pattern 3 and the tips of the three corners (protrusions) of one triangular island pattern 4 are close to each other and face each other. Three discharge gaps are formed.

  Here, since each protrusion part of the 1st conductive pattern 3 does not protrude outside, it becomes possible to arrange | position and mount a circuit component in the vicinity of the outside of the 1st conductive pattern 3, and a higher density mounting. Can be realized. In addition, since the degree of freedom of component placement increases while maintaining the discharge gap, a more appropriate result can be obtained in terms of board design.

  FIG. 5 shows another example of the pair of discharge gap forming portions 3a and 5a. Here, as the discharge gap forming portion 3 a, one triangular protrusion is formed at one corner of the rectangular first conductive pattern 3. As the discharge gap forming portion 5a, one triangular protrusion is formed on a part of the straight line portion of the grounding power supply wiring pattern 5.

  FIG. 6 shows another example of three pairs of discharge gap forming portions 3a and 5a. Here, as the discharge gap forming portion 3 a, three triangular projections are formed on one side of the rectangular first conductive pattern 3. As the discharge gap forming portion 5a, three triangular protrusions are formed on one side of the straight portion of the power supply wiring pattern 5 for grounding.

  FIG. 7 shows an example of two pairs of discharge gap forming portions 3a and 5a. Here, as the discharge gap forming portion 3a, a triangular shape formed on the opposite two sides of the concave pattern portion processed on one side of the rectangular first conductive pattern 3 toward the inside of the concave pattern. Protrusions are formed. As the discharge gap forming portion 5a, one triangular protrusion is formed on a part of the straight line portion of the grounding power supply wiring pattern 5 so as to be arranged near the opening of the concave pattern portion. In this case, the two triangular projections of the first conductive pattern 3 and the one triangular projection tip of the power supply wiring pattern 5 for grounding face each other close to each other, and two discharges Create a gap.

  FIG. 8 shows an example of four pairs of discharge gap forming portions 3a, 4a, and 5a. This example corresponds to a combination of the three pairs of discharge gap forming portions (3a, 4a) shown in FIG. 4 and the pair of discharge gap forming portions (3a, 5a) shown in FIG. In this case, the three pairs of discharge gap forming portions (3a, 4a) using the island pattern 4 and the pair of discharge gap forming portions (3a, 5a) using the power supply wiring pattern 5 for grounding, Since two types of discharge paths can be formed, discharge can be generated more reliably.

  9A and 9B are a plan view showing an example of the first conductive pattern 3 in the printed circuit board of FIG. 1 and a perspective view schematically showing an example of the conductive component 2 for fixing the board. is there.

  In the first conductive pattern 3, the center portion of the rectangular pattern is missing in a circular shape, and a recess is formed in a part of the substrate surface to determine the position of the conductive component for fixing the substrate corresponding to the missing portion 3 b. The conductive component 2 for fixing the substrate is mounted on the center portion (shaded area in the figure) of the pattern. A protrusion (not shown) as described above is formed on a part of the first conductive pattern 3.

  The conductive component 2 for fixing the substrate has a protrusion 2a that can be fitted in the recess for mounting and positioning the substrate surface at the center of the bottom surface of the cylindrical portion, and is fixed to, for example, metal at the center of the upper surface of the cylindrical portion. It has a screw hole (not shown) that can be screwed to the plate.

<Second Embodiment>
FIGS. 10A and 10B are a plan view and a cross-sectional view schematically showing an example of a conductive pattern for forming a discharge gap of a printed circuit board according to the second embodiment of the present invention. In the second embodiment, when the insulating substrate has a multilayer wiring structure, the first conductive pattern and the second conductive pattern are formed in different layers in the multilayer wiring structure, as compared with the first embodiment. The difference is that the tip portions of the protrusions face each other in the vertical direction. In this example, the first conductive pattern 3 is formed on the upper surface of the substrate having a multilayer wiring structure having a plurality of wiring layers formed by being insulated by the insulating layer 1b, and the second conductive pattern is formed on the wiring layer inside the substrate. Yes. In this case, as described above with reference to FIG. 9A, the first conductive pattern 3 has a circular pattern with a central portion missing in a circular shape, and a protrusion 3a on the inner periphery of the missing portion 3b. A pattern in which is formed can be used. In this case, it is preferable to insulate the protruding portion 3a so that the bottom surface portion of the fixing component 2 and the protruding portion 3a do not directly touch each other. As the second conductive pattern, either the island pattern 4 as shown in FIG. 2 or the pattern in which the protrusion 5a is formed on a part of the grounding power supply wiring pattern 5 as shown in FIG. 5 is used. it can. This makes it possible to realize further high-density mounting.

  FIG. 11A is an enlarged plan view showing the central region of the first conductive pattern shown in FIG. FIG. 11B is a cross-sectional view showing a state in which the conductive component for fixing the substrate is soldered to the first conductive pattern along the direction of the arrow BB in FIG. When the conductive component 2 for fixing the substrate is fixed to the first conductive pattern 3 with the solder 11, a solder resist 12 having an insulating property such as a resin is applied on at least the upper surface of the protruding portion including the protruding portion 3a. Keep it. In this way, even if the protruding portion 3a is buried in the solder 11, it is possible to prevent the bottom surface portion of the fixing component 2 and the protruding portion 3a from touching directly, so that a discharge gap can be reliably formed. Can do.

  Hereinafter, an embodiment will be described in detail with reference to FIGS. 1 and 3.

  The printed wiring circuit board 1 has a power wiring pattern and a signal wiring pattern (not shown) formed by printed wiring on an insulating substrate, and an LED display device (not shown) is mounted on the surface side. .

  On the back side of the printed circuit board 1, in addition to the grounding power supply wiring pattern (not shown), the first conductive pattern 3 and islands that are electrically isolated from the surrounding wiring pattern and exist in an island shape The pattern 4 is simultaneously formed in the same process.

  Further, on the back side of the printed circuit board 1, a conductive component 2 for fixing the board, a connector or the like (not shown) is mounted. The conductive component 2 for fixing the substrate has a base end fixed to the first conductive pattern 3 by soldering, and a screw hole (not shown) that can be fixed to the fixing plate 6 by screws 7 at the distal end side. It is a metal surface mount spacer having the following. In this case, the first conductive pattern 3 also has a function as a fixing member of the conductive component 2.

  As shown in FIG. 3, each of the first conductive pattern 3 and the island pattern 4 has discharge gap forming portions 3a and 4a that project in a triangular shape, and the protruding tip portions are close to each other. Thus, three pairs of discharge gaps are formed. Here, as the discharge gap forming portion 3 a, three triangular projections are formed on one side of the rectangular first conductive pattern 3. As the discharge gap forming portion 4a, one corner of each of the three island-like patterns 4 formed in a triangular shape is used.

  Incidentally, when a test is performed such that the distance of the discharge gap is, for example, 1 to 2 mm and an electrostatic discharge of, for example, several Kv is applied to the conductive component 2, circuit components and wiring patterns around the conductive component 2 It was possible to suppress the discharge to and protect them.

  The present invention is not limited to the above-described embodiments and examples, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. It goes without saying that it is a thing.

  The printed wiring circuit board of the present invention is not limited to the case where the LED display device described above is mounted, but is generally applicable when circuit components are mounted.

The perspective view which shows roughly an example of the state assembled so that the printed wiring circuit board concerning the 1st Embodiment of this invention may be attached to a fixed board. The perspective view which shows an example of the conductive pattern for discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The perspective view which shows the other example of the conductive pattern for the discharge gap formation formed in the single side | surface side of the printed wiring circuit board of FIG. The top view which shows an example of the 1st conductive pattern in the printed wiring circuit board of FIG. 1, and the perspective view which shows schematically an example of the electroconductive component for board | substrate fixation. The top view and sectional drawing which show roughly an example of the conductive pattern for the discharge gap formation of the printed wiring circuit board concerning the 2nd Embodiment of this invention. The top view which expands and shows the center area | region of the 1st conductive pattern shown in FIG. 10, and sectional drawing which shows a mode that the conductive component for board | substrate fixation is soldered to the 1st conductive pattern.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Printed wiring circuit board, 2 ... Conductive component for board | substrate fixation (metal surface mounting spacer), 3 ... 1st conductive pattern, 4 ... 2nd conductive pattern (island pattern 4), 3a, 4a: Projection for forming a discharge gap.

Claims (9)

A printed wiring circuit board in which a wiring pattern is formed by printed wiring on an insulating substrate,
On the insulating substrate, a first conductive pattern for fixing the insulating substrate formed by being electrically insulated from the wiring pattern, and a second conductive pattern formed adjacent to the first conductive pattern. A pattern, and
At least one protrusion is formed on each of the first conductive pattern and the second conductive pattern, and the tips of the protrusions are close to each other. .   2. The printed circuit board according to claim 1, wherein a tip end of the first conductive pattern and a tip end of the second conductive pattern are close to each other at 1 mm or less.   The printed wiring circuit board according to claim 1, wherein the second conductive pattern is an island pattern electrically insulated from a surrounding wiring pattern.   The printed wiring circuit board according to claim 1, wherein the second conductive pattern uses a part of a grounding power supply wiring pattern.   The printed wiring circuit board according to claim 1, wherein a shape of the protrusion is a triangular pattern.   2. The printing according to claim 1, wherein the insulating substrate has a multilayer wiring structure, and the first conductive pattern and the second conductive pattern are formed in different layers in the multilayer wiring structure. Wiring circuit board. In the first conductive pattern, a triangular projection is formed on each side of the concave pattern formed on one side of the square pattern toward the inside of the concave pattern,
The second conductive pattern is one triangular island pattern formed in the vicinity of the opening of the concave pattern portion of the first conductive pattern,
The three triangular protrusions in the first conductive pattern and the three protrusion-shaped tips in the triangular island pattern respectively correspond to each other and face each other in close proximity to each other. The printed wiring circuit board according to 2 or 3.   8. The printed circuit board according to claim 1, wherein the first conductive pattern is attached by electrically connecting conductive parts for fixing the insulating substrate. 9. .   The conductive component for fixing the substrate is a metal surface mounting spacer having a configuration in which a base end portion is fixed to the first conductive pattern by soldering and a distal end side can be fixed to a fixing plate. The printed circuit board according to claim 8.

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