WO2025165046A1 - Printed circuit board - Google Patents

Abstract

The printed circuit board according to an embodiment of the present invention comprises: a substrate unit having first and second insulating layers formed on both sides thereof and having a circuit layer formed between the first and second insulating layers; electronic equipment components mounted in an exposed region in which the circuit layer is exposed by removing a part of the first insulating layer; and a component reinforcement unit attached to the second insulating layer in the exposed region so as to support electronic equipment components. The component reinforcing unit comprises: a component reinforcement plate bonded to the second insulating layer in the exposed region; a component adhesive layer formed between the second insulating layer and the component reinforcement plate; and a discharge channel for discharging air bubbles in the component adhesive layer. The substrate unit further comprises a pattern fuse unit formed such that a part of the circuit layer can function as a fuse. The pattern fuse unit comprises a melting unit configured to melt faster than other parts of the circuit layer at a predetermined current or higher. Accordingly, the electronic equipment components are prevented from floating, thereby improving the product's reliability and durability.

Description

printed circuit board

The present invention relates to a printed circuit board, and more specifically, to a printed circuit board in which an internal circuit is printed and electrically connected to other components to complete a circuit.

A printed circuit board is a circuit board with internal circuits patterned and printed to fix and connect multiple electronic components in a standardized manner, and it mechanically and electrically connects multiple circuits to realize miniaturization and weight reduction of electrical products.

Printed circuit boards (PCBs) offer the advantages of stable circuit characteristics, no risk of miswiring, and low production costs. These numerous advantages have led to their widespread use in diverse fields and their becoming an essential component in all electronic devices. In particular, the recent trend toward miniaturization and lightweight design has led to an increase in the use of flexible PCBs.

On one side of these printed circuit boards, electrical components such as connectors and terminals are mounted and connected to each circuit, and at this time, in order to prevent damage to the printed circuit board, especially the flexible printed circuit board, a reinforcing plate is attached to the other side using an adhesive. However, when soldering to electrically connect the electrical components and each circuit, there was a problem in that the temperature increased due to soldering, causing the air bubbles in the adhesive to expand, which significantly reduced the stability of the electrical connection with the electrical components, and caused defects as the flatness decreased.

Accordingly, the demand for lighter printed circuit boards that can stably install various electronic components is increasing.

The present invention has been devised to solve the above problems, and aims to provide a printed circuit board having improved product reliability and productivity and being lightweight overall.

In order to solve the above problem, the present invention provides a printed circuit board including a substrate portion having first and second insulating layers formed on both sides and a circuit layer formed between the first and second insulating layers; an electrical component mounted on an exposed area where the circuit layer is exposed by removing a portion of the first insulating layer; and a component reinforcement portion attached to a second insulating layer of the exposed area and supporting the electrical component; wherein the component reinforcement portion includes a component reinforcement plate bonded to the second insulating layer of the exposed area, a component adhesive layer formed between the second insulating layer and the component reinforcement plate, and a discharge path for discharging air bubbles in the component adhesive layer; and wherein the substrate portion further includes a pattern fuse portion formed in a form in which a portion of the circuit layer can function as a fuse, and wherein the pattern fuse portion includes a melting portion that melts faster than other portions of the circuit layer at a current above a certain level.

The above-mentioned electric component is formed with a connection part that is electrically contacted by soldering with the circuit layer exposed in the above-mentioned exposed area, and it is preferable that the discharge path is formed corresponding to the position of the connection part.

In the above exhaust path, it is effective to form an air tunnel in which the component adhesive layer is removed from the position of the connecting portion to one end of the exposed area.

It is preferable that the above exhaust path is formed with an air hole penetrating the component reinforcement plate and the component adhesive layer at the location of the connecting portion.

It is effective that the above discharge path is formed by a horizontal discharge path formed by removing the component adhesive layer at the location of the connecting portion, and a vertical discharge path formed by penetrating the component reinforcement plate so as to be connected to the horizontal discharge path.

In the above exposure area, a fixed circuit is formed to which the above electric component is fixed by soldering, and the discharge path is additionally formed corresponding to the position of the fixed circuit.

It is preferable that the above pattern fuse part further include a connection pad formed at both ends of the melting part.

It is effective that the width of the above-mentioned connection pad is wider than the width of the above-mentioned melting part.

At least one of the first insulating layer and the second insulating layer on which the connection pad is formed may not be formed, so that the connection pad may be exposed to the outside.

It is effective to apply a protective coating to the upper side of the above connection pad.

It is preferable that the above pattern fuse portion further include an interference prevention portion that surrounds the melting portion and from which the circuit layer is removed.

It is effective that the above pattern fuse portion further includes a concentrated melting portion in which at least one of the first insulating layer and the second insulating layer of at least a portion of the melting portion is open.

It is desirable that a protective coating liquid be applied to the open surface of the above-mentioned concentrated melting section.

It is effective that the above pattern fuse portion further includes an overflow prevention portion formed as a closed curve surrounding the above pattern fuse portion and protruding from at least one of the first insulating layer and the second insulating layer.

The above pattern fuse part may be implemented by including a connection wiring connected to one end of the melting part; and a connection pad formed in connection with the connection wiring.

A fuse reinforcement part formed on one side of the pattern fuse part and supporting the pattern fuse part is further included; the fuse reinforcement part includes a fuse adhesive layer attached to at least one surface of the first and second insulating layers of the pattern fuse part; and a fuse reinforcement plate attached to the fuse adhesive layer.

It is effective that the above fuse adhesive layer is formed in a portion other than a portion corresponding to the melting portion, and a void is formed in a portion corresponding to the melting portion.

It is preferable that the above fuse reinforcement part further include a fuse reinforcement part fixing hole formed by penetrating the fuse reinforcement part.

According to the problem-solving means of the present invention as discussed above, various effects, including the following, can be expected. However, the present invention is not established only if it exhibits all of the following effects.

The printed circuit board of the present invention has a discharge path formed to discharge air bubbles in the adhesive layer corresponding to the exposed area where the electrical component is mounted, thereby preventing the electrical component from lifting and providing a more stable electrical connection with the circuit layer.

In addition, it significantly reduces the defect rate by preventing the flatness of the circuit board from being lowered due to the lifting of the electrical components, and at the same time, it secures the fixing strength of the electrical components, thereby improving durability against continuous vibration caused by vehicle operation.

In addition, in another embodiment, a discharge path penetrating the reinforcing plate is formed so that air bubbles generated in the bonding layer are immediately removed in the direction of lamination, thereby maximizing the above-described effect.

In addition, the present invention can implement a lighter printed circuit board than a conventional chip fuse by having a pattern fuse section.

Additionally, there is an advantage in that defects in the pattern fuse part can be tested in advance during the manufacturing stage through the connection pad.

In addition, by providing an interference prevention unit, a concentrated melting unit, and an overflow prevention unit, the reliability of the melting characteristics of the melting unit can be increased.

Figure 1 is a schematic diagram of a printed circuit board of the first embodiment of the present invention.

Figure 2 is an exploded perspective view of part A of Figure 1.

Figure 3(a) is a plan view of the reinforcement part of part A of Figure 1.

Figure 3(b) is a cross-sectional view of part A of Figure 1 in the Ⅲ-Ⅲ direction.

Figure 4(a) is a plan view of a reinforcement part showing a modified example of the exhaust path.

Figure 4(b) is an exploded perspective view of Figure 4(a).

Fig. 5(a) is a plan view of a reinforcement part showing another modified example of the exhaust path of Fig. 1.

Figure 5(b) is an exploded perspective view of Figure 5(a).

Figure 6(a) is a cross-sectional view taken along the direction Ⅵa-Ⅵa with the electrical components mounted in Figure 4(a).

Figure 6(b) is a cross-sectional view taken along the Ⅵb-Ⅵb direction with the electric components mounted in Figure 5(a).

Fig. 7 is an enlarged view of the pattern fuse part of Fig. 1.

Fig. 8 is a cross-sectional view taken along the cutting line VIII-VIII of Fig. 7.

Figure 9 is a cross-sectional view taken along the cutting line IX-IX of Figure 7.

Fig. 10 is a plan view showing a modified example of the connection pad of Fig. 7.

Figures 11 to 14 illustrate the pattern fuse portion of the printed circuit board of the second embodiment.

Figure 11 is a plan view of the pattern fuse section.

Figure 12 is a bottom view of Figure 8.

Fig. 13 is a cross-sectional view taken along the cutting line XIII-XIII of Fig. 11.

Figure 14 is a plan view of the adhesive layer of Figure 11.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. However, descriptions of well-known functions or configurations will be omitted so as not to obscure the gist of the present invention.

Also, for convenience of explanation, the direction in which the printed circuit board is extended is defined as the extension direction, the direction in which the insulating layer and the circuit layer are laminated is defined as the lamination direction, the direction in which the connector is mounted is defined as the upper side of the lamination direction, and the direction in which the reinforcement is formed is defined as the lower side of the lamination direction.

FIG. 1 is a schematic diagram of a printed circuit board of a first embodiment of the present invention, FIG. 2 is an exploded perspective view of part A of FIG. 1, FIG. 3(a) is a plan view of a reinforcement part of part A of FIG. 1, FIG. 3(b) is a cross-sectional view of part A of FIG. 1 in the direction Ⅲ-Ⅲ, FIG. 4(a) is a plan view of a reinforcement part showing a modified example of an exhaust path, FIG. 4(b) is an exploded perspective view of FIG. 4(a), FIG. 5(a) is a plan view of a reinforcement part showing another modified example of an exhaust path of FIG. 1, FIG. 5(b) is an exploded perspective view of FIG. 5(a), FIG. 6(a) is a cross-sectional view in the direction Ⅵa-Ⅵa in a state where an electrical component is mounted in FIG. 4(a), and FIG. 6(b) is a cross-sectional view in the direction Ⅵb-Ⅵb in a state where an electrical component is mounted in FIG. 5(a). Cross-sectional view, Fig. 7 is an enlarged view of the pattern fuse part of Fig. 1, Fig. 8 is a cross-sectional view along the cutting line VIII-VIII of Fig. 7, Fig. 9 is a cross-sectional view along the cutting line IX-IX of Fig. 7, and Fig. 10 is a plan view showing a modified example of the connection pad of Fig. 7.

Referring to these drawings, a printed circuit board (10) of one embodiment of the present invention includes a substrate portion (100) in which first and second insulating layers (101, 102) are formed on both sides and a circuit layer (103) is formed between the first and second insulating layers (101, 102), an electrical component (200) mounted on an exposed area (131) in which a portion of the first insulating layer (101) is removed to expose the circuit layer (103), and a component reinforcement portion (300) formed on one side of the exposed area (131) to support the electrical component (200).

The substrate portion (100) includes a circuit layer (103) in which internal circuits are formed in a pattern, a first insulating layer (101) is laminated on the upper side of the circuit layer (103) in the stacking direction, and a second insulating layer (102) is laminated on the lower side of the circuit layer (103) in the stacking direction to electrically connect the external components and the circuit layer (103) to complete a plurality of circuits. At this time, the first and second insulating layers (101, 102) support the circuit layer (103) formed thinly to prevent the internal circuits from being damaged, such as by a short circuit, and protect the circuit layer (103) by preventing phenomena, such as a short circuit with other surrounding components. Therefore, the circuit layer (103) is formed in a pattern with a plurality of internal circuits, and the first and second insulating layers (101, 102) are formed to cover the entire internal circuits on both sides in the stacking direction so that not all of the circuit layers (103) are exposed to the outside.

In the above, each component that constitutes the substrate portion (100) in the thickness direction has been described, and below, each component that is arranged on a plane according to the shape or function of the substrate portion (100) will be described in more detail.

The substrate portion (100) includes a body portion (110) formed vertically by the first and second insulating layers (101, 102) and the circuit layer (103) described above, a component mounting portion (130) on which the above-described electric component (200) is mounted according to function in the horizontal direction, and a pattern fuse portion (150) formed in a form in which a portion of the circuit layer (103) can function as a fuse.

The pattern fuse part (150) includes a melting part (151) that melts faster than other parts of the circuit layer (103) when a certain current is applied, connection pads (152) formed at both ends of the melting part (151), an interference prevention part (153) that surrounds the melting part (151) and from which the circuit layer (103) is removed, a concentrated melting part (154) in which at least one of the first insulating layer (101) and the second insulating layer (102) of at least a portion of the melting part (151) is open, and an overflow prevention part (155) that is formed as a closed curve surrounding the pattern fuse part (150) and protrudes from at least one of the first insulating layer (101) and the second insulating layer (102).

The pattern fuse unit (150) may be formed by a single melting unit (151), but may also be formed by clustering multiple melting units (151) as shown in Fig. 7. The interference prevention unit (153) and the overflow prevention unit (155) are formed in a form that surrounds the entire multiple melting units (151).

The melting portion (151) is formed to be smaller than the cross-sectional area of other circuit wirings (104) of the circuit layer (103), so that when a certain current or more flows, it is fused before other circuit wirings (104). In addition, as illustrated in Fig. 7, the melting portion (151) is formed to have a thin line width to increase resistance, and is formed in a zigzag shape to increase the length. A plurality of such melting portions (151) may be formed. By forming the pattern fuse portion (150) as described above, not only can the weight be reduced compared to the chip fuse, but also the manufacturing cost can be reduced, which is an advantage.

The connection pad (152) is formed to have a size wider than the width of the melting portion (151) and is formed at each end of the melting portion (151). The connection pad (152) is necessary for performance testing of the pattern fuse and is used for resistance testing of the melting portion (151) during or after the process. Therefore, the connection pad (152) may be continuously exposed, or may be exposed only during the test stage during the manufacturing process to prevent unnecessary contamination. That is, at least one of the first insulating layer (101) and the second insulating layer (102) on which the connection pad (152) is formed may not be formed, so that the connection pad (152) is exposed to the outside, or, as shown in FIG. 8, a protective coating solution (157) may be applied to the upper side of the connection pad (152) after testing so that the connection pad (152) is not exposed after manufacturing. Alternatively, after testing with only one of the first and second insulating layers (101, 102) formed, the remaining insulating layer may be thermally bonded so that the connection pad (152) is not exposed. Since the shape of the connection pad (152) is a test point for resistance measurement, it can be formed in various shapes such as square, circular, and polygonal as needed.

In addition, as illustrated in FIG. 10, the connection pad (152) may not be formed directly at both ends of the melting portion (151), but may be formed separately. That is, the pattern fuse portion (150) may include a connection wire (1156) connected to one end of the melting portion (151), and a connection pad (1152) formed in connection with the connection wire (156). The connection pad (1152) is formed at a location away from the melting portion (151), and the connection wire (156) connects the melting portion (151) and the connection pad (1152), so that the connection pad (152), which occupies a large area, can be placed outward, which has the advantage of increasing the degree of freedom in design.

The interference prevention section (153) is the circuit layer (103) surrounding the molten section (151), i.e., the area from which the conductive conductor has been removed. By removing the conductive conductor from the area surrounding the molten section (151) in this way, the electrical characteristics of the pattern fuse can be maintained constant. When a conductor is present in the molten section (151), the electrical characteristics change due to the influence of heat dissipation, etc., and thus the interference prevention section (153) prevents such changes.

The concentrated melting section (154) is a section in which at least one of the first and second insulating layers (101, 102) of a certain area, in the present invention the central area, of the melting section (151) is opened. By being opened in this way, the melting characteristics of the melting section (151) are prevented from being changed by the first and second insulating layers (101, 102). In addition, in order to protect the opened section, a protective coating solution (157) may be applied to the open surface of the concentrated melting section (154).

The overflow prevention part (155) is formed to protrude upward on one side of the first and second insulating layers (101, 102), that is, the side on which the protective coating solution (156) is applied, so as to surround the pattern fuse part (150). The manufacturing method is formed to protrude upward on the first and second insulating layers (101, 102) by a method such as silkscreen. The overflow prevention part (155) prevents the protective coating solution (157) applied to the upper side of the concentrated melting part (154) or the connection pad (152) from overflowing to other parts of the circuit board. Alternatively, when applying the coating solution to the upper surface of the pattern fuse part (150) to secure the performance of the pattern fuse part (150), it provides a guideline for the coating area, prevents coating of unnecessary areas, reduces the amount of coating solution required, and makes it easier to recognize and judge defects when the coating solution overflows.

As described above, one embodiment of the present invention can reduce the overall weight compared to when using a chip fuse by having a pattern fuse section.

Additionally, there is an advantage in that defects in the pattern fuse part can be tested in advance during the manufacturing stage through the connection pad.

In addition, by providing an interference prevention section, a concentrated melting section, and an overflow prevention section, the reliability of the melting characteristics of the melting section can be increased.

The component mounting portion (130) includes an exposed area (131) formed by removing a portion of the first insulating layer (101) of the body portion (110), an exposed circuit (132) positioned in the exposed area (131) and in which the circuit layer (103) is directly electrically connected to the electrical component (200), and a fixed circuit (133) formed in the circuit layer (103) for fixing the electrical component (200) and exposed by the exposed area (131).

Here, the exposed circuit (132) is formed of copper foil and extends in the extension direction to expose a portion of the internal circuit of the body portion (110) and is electrically connected to the electric component (200), but the fixed circuit (133) is formed of a circuit layer (103) in the form of copper foil, but is not connected to the internal circuit and is only used for fixing the electric component (200).

Accordingly, the exposure area (131) is formed corresponding to the size of the mounted electrical component (200), and, if necessary, an area where the exposed circuit (132) is exposed and an area where the fixed circuit (133) is exposed can be formed separately, and preferably, a plurality of exposure areas (131) are formed so that each of the exposed circuits (132) and the fixed circuit (133) is exposed in a partitioned manner, thereby minimizing exposure of a portion other than a portion connected to the electrical component (200) and ensuring the stability of the circuit layer (103).

In summary, the printed circuit board (10) of the present invention forms an exposed area (131) in which the circuit layer (103) is exposed on the first insulating layer (101) laminated on one side of the circuit layer (103), thereby directly connecting to an electric component (200) and easily forming a plurality of circuits with an external device.

The electrical component (200) refers to a connector that extends to one side of the printed circuit board (10) and is directly electrically connected to the exposed circuit (131) to relay the connection between an external device and the circuit layer (103), or a sensor or element that measures the status of a connected device.

To this end, the electric component (200) is formed by a component body (210), a connection portion (220) exposed on one side of the component body (210) and electrically connected to each of the exposed circuits (132) by soldering, and a fixing portion (230) fixed to the fixed circuit (133) by soldering.

At this time, the connecting portion (220) is formed in multiple pieces so as to be connected to multiple circuits forming the circuit layer (103), thereby forming multiple circuits that serve as passages for electrical signals, and the fixed portion (230) is configured to be exposed on the outside of the electric component (200) and simply connected to the fixed circuit (133), so that even when connected to the fixed circuit (133) by soldering, no circuit is formed.

The component reinforcement part (300) is attached to the second insulating layer (102) corresponding to the position of the exposed area (131) to support the electrical component (200) and prevent damage such as tearing of the flexible printed circuit board (10) due to mounting of the electrical component (200).

The above-described component reinforcement part (300) is characterized by being formed by a component reinforcement plate (310) installed on the second insulating layer (102) of the exposed area (131), a component adhesive layer (320) formed between the second insulating layer (102) and the component reinforcement plate (310), and a discharge path (330) for discharging air bubbles within the component adhesive layer (320). The component reinforcement part (300) supports the mounted electrical component (200) and prevents deformation that may occur in the printed circuit board (10) during soldering, thereby significantly improving product reliability and durability.

The component reinforcement plate (310) has a hard physical property so that it stably supports an electrical component (200) having a weight greater than a certain level, such as a connector, even when mounted, and preferably has a width that can accommodate all of the multiple exposed areas (131) so as to support the entire area of the electrical component (200). A plate fixing hole (311) is formed through the component reinforcement plate (310). The plate fixing hole (311) is formed by penetrating the component adhesive layer (320) and the substrate portion (100). The plate fixing hole (311) is formed in the number and position required to fix the printed circuit board (10). A boss or the like formed on a counterpart to which the printed circuit board (10) is fixed is inserted into the plate fixing hole (311) and fused, thereby fixing the printed circuit board (10).

The component adhesive layer (320) is formed between the second insulating layer (102) and the component reinforcement plate (310) and serves to fix the component reinforcement plate (310) to the second insulating layer (102). The component adhesive layer (320) is formed of a double-sided tape material having a certain thickness, and a release paper is attached to both sides before attachment, and is attached after the release paper is removed. The component adhesive layer (320) is formed by having a discharge channel (330) penetrating therethrough for discharging air bubbles within the component adhesive layer (320).

At this time, as the electrical component (200) is mounted by soldering while the component reinforcement plate (310) is attached, the temperature of the exposed area (131) rises, and accordingly, air bubbles in the component adhesive layer (320) expand, causing lifting in the mounting portion of the electrical component (200).

In general, a printed circuit board (10) is printed with solder paste (20) in advance on an exposed area (131), and then a reflow soldering process is used to re-melt the solder paste (20) by supplying external heat to join the electrical components (200). The heat supplied at this time has a temperature of approximately 250°C, and in this case, the bubbles in the component bonding layer (320) expand to about twice their volume.

The exhaust passage (330) is a passage for discharging expanded bubbles within the component bonding layer (320). It is formed corresponding to the position of the exposed circuit (131), that is, the connection portion (220) of the electrical component (200) and the connection portion (220) where the circuit layer (103) is joined by soldering, and is connected to the outside to discharge bubbles to the outside along the exhaust passage (330).

Specifically, the exhaust path (330) of the first embodiment is formed as an air tunnel (331) that extends from the position of the connecting portion (220) and the fixing portion (230) of the component adhesive layer (320) to one end of the component adhesive layer (320). When the temperature rises due to soldering, the bubbles in the component adhesive layer (320) expand and gradually increase in size as they merge with other surrounding bubbles. At this time, the expanded bubbles move to the exhaust path (330) where the relative pressure is low because the pressing force of the component reinforcement plate (310) is not generated, and are discharged to the outside through the exhaust path (330) to prevent the occurrence of lifting in the mounting portion of the electric component (200).

In addition, since the discharge path (330) is formed by removing the component adhesive layer (320), the bonding area is reduced, so it is preferable that the discharge path (330) be formed of a plurality of air tunnels (331) connected to the end closest to the connection part (220) and the fixing part (230). In the case of the discharge path (330) connected to the connection part (220), considering that expanded bubbles merge with surrounding bubbles, it is preferable that it be formed in the center of the connection part (220) to secure a contact area while also discharging bubbles expanded in the periphery.

Fig. 4(a) is a side view of a reinforcement part showing a modified example of an exhaust path, and Fig. 4(b) is an exploded perspective view of Fig. 4(a).

As illustrated in FIG. 4, the exhaust path (1330) of the modified example is formed by a first air hole (1331) that simultaneously penetrates the component reinforcement plate (310) and the component adhesive layer (320) corresponding to the position of the connecting portion (220), and a second air hole (1332) that simultaneously penetrates the component reinforcement plate (310) and the component adhesive layer (320) corresponding to the position of the fixing portion (230), thereby discharging expanding air bubbles in the stacking direction.

At this time, for processability and peripheral bubble removal, it is preferable that the first and second air holes (1331, 1332) are formed to be connected to each other, and the discharge path (1330) of another embodiment is formed by simultaneously penetrating the component reinforcement plate (310) and the component adhesive layer (320), so that the length of the path through which bubbles are discharged can be minimized, enabling more rapid bubble discharge.

As illustrated in FIG. 5, the discharge path (2330) of another modified example is formed by a horizontal discharge path (2331) formed by removing the component adhesive layer (320) corresponding to the positions of the connecting portion (220) and the fixing portion (230), and a vertical discharge path (2332) formed by penetrating the component reinforcement plate (310) in the thickness direction so as to be in communication with one side of the horizontal discharge path (2331).

More specifically, the horizontal discharge path (2331) is formed by starting from the position of the connecting portion (220) and the fixing portion (230) and extending to one side by a predetermined length, and the vertical discharge path (2332) is formed to communicate with the horizontal discharge path (2331) corresponding to the position of the connecting portion (220) and the fixing portion (230), so that bubbles are quickly discharged in the axial direction in the part where soldering is performed, and at the same time, the horizontal discharge path (2331) is formed to have a predetermined length, thereby reducing the movement path of bubbles expanded around the connecting portion (220) and the fixing portion (230), thereby enabling smooth discharge.

In summary, the discharge path (330) of the printed circuit board (10) of the present invention can be formed in various embodiments capable of discharging expanded bubbles within the component adhesive layer (320). In this case, the discharge path (330) of one embodiment of FIGS. 1 to 3 is formed to have a certain length so that the component reinforcement plate (310) can support the entire exposed area (131) to maintain support, and also allows bubbles around the connection portion (220) and the fixing portion (230) to be smoothly discharged. However, since the bubbles are discharged while moving along the air tunnel (331), it is difficult to discharge them more quickly than with the discharge path (330) formed in the axial direction.

In addition, the exhaust path (1330) of the modified example of FIG. 4 is formed with the first and second air holes (1331, 1332) that connect both the connecting portion (220) and the fixed portion (230), so that the support area of the component reinforcing plate (310) is reduced the most, but the discharge of expansion bubbles around the connecting portion (220) and the fixed portion (230) is smooth, and the entire exhaust path (1330) is formed to be open in the axial direction, so that the bubbles are quickly discharged.

In addition, the exhaust path (2330) of another modified example of FIG. 5 is formed by a horizontal exhaust path (2331) formed by removing the component adhesive layer (320) at the location of the connecting portion (220) and the fixing portion (230), and a vertical exhaust path (2332) connected to the horizontal exhaust path (2331) at the location of the connecting portion (220) and the fixing portion (230), thereby minimizing the reduction in the support area and at the same time forming a vertical exhaust path (2332) that is axially open at the location of the connecting portion (220) and the fixing portion (230) where soldering is directly performed, thereby allowing air bubbles to be quickly discharged.

At this time, the horizontal discharge path (2331) is formed to extend a predetermined length to one side from the position of the connecting portion (220) and the fixing portion (230) so that air bubbles around the area where soldering is directly performed are also smoothly discharged.

In other words, the discharge paths (330, 1330, 2330) of different embodiments have the same purpose, function, and effect, but the support area of the component reinforcement plate (310) and the air bubble discharge path are different, so that the most suitable example can be selected by considering the type of the mounted electrical component (200) and the size and installation location of the printed circuit board (10).

Accordingly, the printed circuit board (10) of the present invention has a discharge path (330) for discharging air bubbles in the component adhesive layer (320) that expands during the process of mounting the electrical component (200), thereby ensuring electrical connection stability between the electrical component (200) and the circuit layer (103), and also stably fixing the component reinforcement portion (300), thereby improving the reliability and durability of the product.

Furthermore, it has the effect of preventing defects from occurring due to the flatness of the printed circuit board (10) being lowered by bubbles, and also solving problems such as a decrease in tensile strength and a decrease in electrical connection stability with the electric component (200), thereby improving the reliability of an external device connected to the printed circuit board (10).

FIGS. 11 to 14 illustrate a pattern fuse portion of a printed circuit board of a second embodiment. FIG. 11 is a plan view of the pattern fuse portion, FIG. 12 is a bottom view of FIG. 8, FIG. 13 is a cross-sectional view taken along cutting line XIII-XIII of FIG. 11, and FIG. 14 is a plan view of the adhesive layer of FIG. 11.

The printed circuit board of the second embodiment has the same configuration as the first embodiment except for the pattern fuse portion. Therefore, only the pattern fuse portion and the distinctive configuration are described.

The printed circuit board of the second embodiment is characterized in that it further includes a fuse reinforcement part (400) formed on one side of the pattern fuse part (150) to support the pattern fuse part (150).

The above fuse reinforcement part (400) includes a fuse adhesive layer (420) attached to at least one surface of the first and second insulating layers (101, 102) of the pattern fuse part (150), and a fuse reinforcement plate (410) attached to the fuse adhesive layer (420).

The above fuse adhesive layer (420) is formed in the remaining portion except for the position corresponding to the melting portion (151), and forms a void (425) in the position corresponding to the melting portion (151). That is, the fuse adhesive layer (420) includes a fuse adhesive layer body (421) in the shape of a square ring that surrounds the void (425), as illustrated in FIG. 11.

The fuse reinforcement plate (410) is formed of the same material as the component reinforcement plate (310).

The above fuse reinforcement part (400) includes a fuse reinforcement part fixing hole (430) formed by penetrating the fuse reinforcement part (400). That is, the fixing hole (430) is formed by penetrating the pattern fuse part (150), the fuse adhesive layer (420), and the fuse reinforcement plate (410). The fixing holes (430) are formed in the number and position required to fix the pattern fuse part (150). A boss or the like formed on a counterpart to which the pattern fuse part (150) is fixed is inserted into the fixing hole (430) and fused, thereby fixing the pattern fuse part (150).

As described above, the printed circuit board of the second embodiment can maintain the flatness of the pattern fuse and firmly fix it to the counterpart by providing a fuse reinforcement portion (400) in the pattern fuse portion (150). In addition, by providing a void portion (421), the fuse adhesive layer (420) is attached to the melting portion (151), thereby preventing changes in melting characteristics and current-conducting characteristics that may occur. In particular, when the melting portion (151) is melted, the fuse adhesive layer (420) is prevented from being carbonized due to high temperature and affecting other circuits.

Although the preferred embodiments of the present invention have been described above as examples, the scope of the present invention is not limited to these specific embodiments, and any modifications that may be appropriately made within the scope described in the claims fall within the scope of protection of the present invention.

Claims (18)

A substrate portion (100) in which first and second insulating layers (101, 102) are formed on both sides and a circuit layer (103) is formed between the first and second insulating layers (101, 102); An electrical component (200) mounted on an exposed area (131) where the circuit layer is exposed by removing a portion of the first insulating layer (101); and It includes a component reinforcement part (300) attached to the second insulating layer (102) of the above exposure area (131) and supporting the above electric component (200); The above component reinforcement part (300) It includes a component reinforcement plate (310) bonded to the second insulating layer (102) of the above-mentioned exposure area (131), a component adhesive layer (320) formed between the second insulating layer (102) and the component reinforcement plate (310), and a discharge path (330, 1330, 2330) for discharging air bubbles within the component adhesive layer (320). The above substrate (100) is It further includes a pattern fuse portion (150) formed in a form that allows a portion of the above circuit layer (103) to function as a fuse. A printed circuit board characterized in that the above pattern fuse portion (150) includes a melting portion (151) that melts faster than other portions of the circuit layer (103) when a certain current is applied. In the first paragraph, The above-mentioned electric component (200) A connection portion (220) is formed by soldering and electrically contacting the circuit layer (103) exposed to the above exposure area (131), The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that it is formed corresponding to the position of the above connection portion (220). In the second paragraph, The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that the above component adhesive layer (320) is formed as an air tunnel (331) removed from the position of the connecting portion (220) to one end of the exposed area (131). In the third paragraph, In the above exposure area (131) A fixed circuit (132) is formed in which the above-mentioned electric component (200) is fixed by soldering, The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that it is additionally formed corresponding to the position of the above fixed circuit (132). In the first paragraph, The above pattern fuse part (150) is Connection pads (152) formed at both ends of the above melting portion (151); A printed circuit board characterized by further including: In paragraph 5, A printed circuit board characterized in that the width of the above connection pad (152) is wider than the width of the above melting portion (151). In paragraph 6, A printed circuit board characterized in that at least one of the first insulating layer (101) and the second insulating layer (102) on which the connection pad (152) is formed is not formed, so that the connection pad (152) is exposed to the outside. In paragraph 7, A printed circuit board characterized in that a protective coating liquid is applied to the upper side of the above connection pad (152). In paragraph 5, The above pattern fuse part (150) is An interference prevention part (153) surrounding the above melting part (151) and from which the circuit layer (103) is removed; A printed circuit board characterized by further including: In paragraph 5, The above pattern fuse part (150) is A concentrated melting portion (154) in which at least one of the first insulating layer (101) and the second insulating layer (102) of at least a portion of the above melting portion (151) is open; A printed circuit board characterized by further including: In paragraph 10, A printed circuit board characterized in that a protective coating liquid is applied to the open surface of the above-mentioned concentrated melting portion (154). In paragraph 5, The above pattern fuse part (150) is An overflow prevention portion (155) formed as a closed curve surrounding the pattern fuse portion (150) and protruding from at least one of the first insulating layer (101) and the second insulating layer (102); A printed circuit board characterized by further including: In the second paragraph, The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that the above component reinforcement plate (310) and the above component adhesive layer (320) are formed with air holes (1331, 1332) penetrating at the location of the connecting portion (220). In the second paragraph, The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that the component adhesive layer (320) is formed by removing the horizontal discharge path (2331) at the location of the connecting portion, and a vertical discharge path (2332) is formed by penetrating the component reinforcement plate (310) so as to be in communication with the horizontal discharge path (2331). In the second paragraph, The above exhaust path (330, 1330, 2330) A printed circuit board characterized in that the component adhesive layer (320) is formed by removing the horizontal discharge path (2331) at the location of the connecting portion, and a vertical discharge path (2332) is formed by penetrating the component reinforcement plate (310) so as to be in communication with the horizontal discharge path (2331). In the first paragraph, A fuse reinforcement part (400) formed on one side of the pattern fuse part (150) and supporting the pattern fuse part (150); Including more, The above fuse reinforcement part (400) is A fuse adhesive layer (420) attached to at least one surface of the first and second insulating layers (101, 102) of the above pattern fuse portion (150); and A fuse reinforcement plate (410) attached to the above fuse adhesive layer (420); A printed circuit board characterized by including: In paragraph 16, A printed circuit board characterized in that the above fuse bonding layer (420) is formed in a portion other than a portion corresponding to the melting portion (151), and a void portion (425) is formed in a portion corresponding to the melting portion (151). In paragraph 16, The above fuse reinforcement part (400) is A fuse reinforcement fixing hole (430) formed by penetrating the above fuse reinforcement (400); A printed circuit board characterized by further including: