JPH11298050A - Metal core printer circuit board with bent and lighting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent defects such as poor contacting due to the occurrence of cracks in a printed circuit at a bent part of a dent and an open edge part, when the dent is drawn. SOLUTION: For a metal core printed circuit board 10 with a dent and a lighting device using it, the width of a common printed circuit 13A and the dimensions in width direction for all N pieces of independent printed circuit 13B to D are almost equal, so that the dimension in width direction of the independent printed circuit is larger, and no cracks occur with a printed circuit at a bent part of the dent and an open edge part when the dent is drawn, without the possibility of such defects as poor contacting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recessed metal core printed circuit board and a lighting fixture using the same.

[0002]

2. Description of the Related Art As one application of a metal core printed circuit board, the field of mounting a light emitting diode has attracted attention, and has been applied to data transfer, illumination, display, and the like. However, with the miniaturization of electronic devices, demands for measures against heat generation and increase in light intensity have increased, and metal core printed circuit boards with depressions using metal core printed circuit boards that have good heat dissipation and good three-dimensional workability such as drawing of depressions The demand for lighting fixtures using this is increasing.

In the above-described metal core printed circuit board with a recess and a lighting device using the same, in the case of a single-color lightning display, in order to mount one light emitting diode chip on the bottom of the recess, a light emitting diode is used. A total of two printed circuits, one common printed circuit for connecting one terminal and one single printed circuit connecting the other terminal of the light emitting diode, are arranged from the bottom of the recess to the outside of the recess, and In the case of three-color light-emitting display, in order to mount three light-emitting diode chips of red, blue and yellow in the recess, one terminal for connecting one terminal of each of the three light-emitting diode chips together is used. A total of four printed circuits, including a common printed circuit of the book and three single printed circuits for individually connecting the other terminals of the three light emitting diodes, respectively, are arranged from the bottom of the recess to the outside of the recess. In this case, only one of the common printed circuit and the single printed circuit is energized at the same time for lighting.

When a metal core printed circuit board is subjected to three-dimensional processing such as drawing of a dent, it is necessary to protect the printed circuit, for example, in the drawn part of the board in order to sufficiently satisfy the performance of the final product. is important.

FIG. 6 is a plan view of an essential part showing an example of a conventional metal core printed circuit board with a depression, and FIG.
8 is a view for explaining an arc length of the printed circuit of FIG. 6 crossing each part of the depression. 9 is a plan view of an essential part showing an example of a lighting device using the metal core printed circuit board with depressions of FIG. 6, and FIG. 10 is a sectional view of the same line DD in FIG.

Conventionally, a metal core printed circuit board obtained by processing a circuit on a copper foil of a metal core copper-clad laminate obtained by laminating a copper foil on a metal core via an insulating layer is placed and fixed on a lower female die such as a press machine. Then, the upper male punch is press-fitted by the downward pressing force (not shown), and the recesses 2 shown in FIGS. 6 and 7 have concentric circular planes and substantially inverted trapezoidal cross sections.
The metal core printed circuit board 100 with the depressions in which 0 is formed is manufactured.

The printed circuit board 100 has a metal core 11
To the printed circuit 130A (130B, 1B) via the insulating layer 12.
30C, 130D) are laminated and integrated. The printed circuits 130A, 130B, 130C, and 130D extend from the bottom surface 22 of the depression 20 through the bent portion 24, the inclined wall surface 23, and the opening edge 21 to the outside of the depression. 1
30A is one common printed circuit, and 130B, 130
C and 130D are three single printed circuits, and only one of the three single printed circuits is used simultaneously with the common printed circuit 130A.

Referring to FIG. 8, a total of four printed circuits 130 are used.
A description will be given of the length of the arc in which A, 130B, 130C, and 130D traverse the bent portion 24 of the depression 20 and the opening edge 21, respectively.

In FIG. 8, the arc length of the common printed circuit 130A across the bent portion 24 is L10A, and the arc length of the common printed circuit 130A across the opening edge 21 is L20A. Similarly, the arc lengths of the single printed circuits 130B, 130C, 130D crossing the bent portion 24 are L10B, L10C, L10D, and the arc lengths crossing the opening edge 21 are L20B, L20C, L20D.

[0010] Then, a metal core printed circuit board 1 with a depression
At 00, the common printed circuit 130A is
The arc length L10A crossing the line is very large, and the single printed circuit 1
The arc lengths L10B, L10C, L10D of 30A, 130B, 130C crossing the bent portion 24 are substantially equal to each other and smaller than the arc length L10A. Similarly, common printed circuit 1
The arc length L20A of 30A crossing the opening edge 21 is very large, and the arc lengths L20B, L20C, L20D of the single printed circuits 130A, 130B, 130C crossing the opening edge 21 are almost equal to each other and compared to the arc length L20A. small. That is, the relationship between the arc lengths can be expressed as in the following [Equation 1]. L10A> L10B = L10C = L10D, and L20A> L20B = L20C = L20D (1) where> means "very large" and = means "
Almost equal. "

[0011] As shown in FIGS. 9 and 10, a lighting fixture 5 using a conventional metal core printed circuit board 100 with depressions.
00 is a depression 20 using the substrate 100 as it is.
The three LED chips 510, 520 and 530 of red, blue and yellow are mounted on the bottom portion 22 of the
One terminal of each of the chips 10, 520, 530 is electrically connected to connection points 540, 550, 560 on the common circuit 130A, and the other terminal of each of the chips 510, 520, 530 is connected to the single printed circuit 130B, 13OC, 1
30D is electrically connected. The three light emitting diode chips 510, 520, and 530 of red, blue, and yellow are not energized and turned on at the same time, and only one of them is turned on.

Light emitting diode chips 510, 520, 5
After the mounting of the lighting device 30, the hollow 20 is filled with a transparent resin 570 such as an epoxy resin or a polyester resin and dried and solidified to complete the lighting device 500.

[0013]

However, in a conventional metal core printed circuit board with a recess and a lighting device using the same, only one of the three color light emitting diode chips is energized and turned on at the same time. However, as shown in FIG. 8, the arc lengths L10A and L10B, L10C and L10D crossing the bent portion 24 are not uniform, and the arc length L crossing the opening edge 21 is not uniform.
Even at 20A and the arc lengths L20B, L20C, and L20D, the arc lengths are not uniform, and the printed circuit in the portion where the crossing arc length is short has a small tensile strength, and is cut off at the folded portion or the opening edge when drawing the dent. Cracks may occur to cause defects such as poor contact.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a metal core printed circuit board with a recess according to the first aspect of the present invention uses a male type and a female type and has a flat concentric plane. In a metal core printed circuit board with a depression formed by forming a depression having a substantially inverted trapezoidal cross section, one of the one extending from the bottom of the depression to the outside of the depression through a bent portion, an inclined wall surface, and an opening edge of the depression. A common printed circuit and N single printed circuits are arranged, and each of the one common printed circuit and the N single printed circuits has substantially the same arc length across the bent portion, and It is characterized in that arc lengths crossing the opening edge are substantially equal. The value of N may be a positive integer of 3 or less.

Next, in a lighting device using the metal core printed circuit board with a recess according to claim 2, at least a light emitting element is mounted on the bottom surface of the recess of the metal core printed circuit board with a recess according to claim 1, and is electrically connected to the printed circuit. It is characterized by the following.
The value of N may be a positive integer of 3 or less.

[0016]

FIG. 1 is a plan view of an essential part showing an example of a metal core printed circuit board with a depression according to the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. FIG.
FIG. 4 is a diagram for explaining an arc length of a printed circuit crossing each part of a depression. FIG. 4 is a plan view of an essential part showing an example of a certifying tool using the metal core printed circuit board with a depression of FIG. 1, and FIG. 5 is a sectional view of the same along line BB of FIG.

According to the present invention, a metal core printed circuit board obtained by processing a circuit of copper foil of a metal core copper-clad laminate obtained by laminating and integrating copper foil on a metal core via an insulating layer is mounted on a lower female die such as a press machine. 1 and 2, and a recess 20 having a circular flat surface and a substantially inverted trapezoidal cross section as shown in FIGS. 1 and 2 was formed. A recessed metal core printed circuit board 10 is manufactured.

The recessed metal core printed circuit board 10 has a printed circuit 13A (1) on a metal core 11 via an insulating layer 12.
3B, 13C, and 13D) are laminated and integrated. Then, the printed circuits 13A, 13B, 13C, and 13D
Bent portion 24 and inclined wall surface 2 starting from the bottom surface 22
3 and the outside of the depression via the opening edge 21. 13A
Are one common printed circuit, and 13B, 13C, 13D
Are three single printed circuits, and only one of the three single printed circuits is used simultaneously with the common printed circuit 13A.

The arc lengths of the four printed circuits 13A, 13B, 13C, 13D of the present invention which cross the bent portion 24 of the recess 20 and the opening edge 21 will be described with reference to FIG.

In FIG. 3, the arc length of the common printed circuit 13A crossing the bent portion 24 is L1A, and the opening edge 21
Is L2A. Similarly, a single printed circuit 1
The arc lengths of 3B, 13C, 13D crossing the bent portion 24 are L1B, L1C, L1D, and the arc lengths crossing the opening edge 21 are L2B, L2C, L2D.

The feature of the metal core printed circuit board 10 having a depression according to the present invention is that the arc length traversing the bent portion 24 is the arc length L1 traversing the common printed circuit 13A and the arc length traversing the single printed circuits 13A, 13B, 13C. L1B, L
1C and L1D are substantially equal to each other, and similarly, the arc length crossing the opening edge 21 is also set to the common printed circuit 13.
The arc length L2A traversing A and the single printed circuits 13B and 13
The arc lengths L2B, L2C, and L2D that traverse C and 13D are substantially equal. That is, the relationship between the arc lengths can be expressed as the following [Equation 2]. L1A = L1B = L1C = L1D, and L2A = L2B = L2C = L2D (2) where = means "substantially equal".

In this embodiment, the metal core 11 is a 0.8 mm thick aluminum plate, the insulating layer 12 is a polyetheretherketone resin, and the printed circuit 13A (13
B, 13C, and 13D) use a copper foil having a thickness of 30 μm processed by a circuit, but the present invention is not limited to this. The metal core 11 has a thickness of about 0.6 to 1.2 mm. Any of copper, iron, silicon steel plate or iron-nickel alloy can be used, and the insulating layer 12 can be any of polypolyetheretherketone resin, polyetherimide resin or polyethersulfone resin,
The printed circuit 13A (13B, 13C, 13D) has 10
A copper foil having a thickness appropriately selected from the range of 100 μm can be used after circuit processing.

As shown in FIGS. 4 and 5, a certifying tool 50 using the metal core printed circuit board 10 having a dent according to the present invention comprises:
Three light emitting diode chips 51, 52, and 53 of red, blue, and yellow are mounted on the bottom surface portion 22 of the recess 20, and one terminal of each of the chips 51, 52, and 53 is connected to the common circuit 1
The other terminals of the chips 51, 52, 53 are electrically connected to the single printed circuits 13A, 13B, 13C, respectively. 3 red, blue and yellow light emitting diode chips 5
1, 52 and 53 are not energized and lit at the same time,
Only one of them is turned on.

After the light emitting diode chips 51, 52, 53 are mounted, the hollow 20 is filled with a transparent resin 57 such as an epoxy resin or a polyester resin and dried and solidified to complete the lighting device 50.

In summary, the relationship between the arc length of one common printed circuit and the three single printed circuits crossing the bent portion of the dent or the edge of the opening is based on the relationship of the conventional [Equation 1]. The relationship of the formula [2] of the present invention is improved, that is, the arc lengths L1A, L1B, L1C, L crossing the bent portion are improved.
1D are made substantially equal to each other, and the arc lengths LA2, LB2, LC2, LD2 crossing the opening edge are made substantially equal to each other, so that the three light-emitting diode chips 51, 52, 53 of red, blue and yellow can be formed. Since the current is not energized and turned on at the same time and only one of them is turned on repeatedly, the current capacity per single printed circuit clearly increases and the current capacity of the common print circuit decreases compared to the conventional one. However, since the current capacity per single printed circuit is ensured, there is no problem in terms of current capacity. Then, the single printed circuits 13B, 13
The width of the single printed circuits 13B, 13C, and 13D is increased by the increase in the arc length traversed by C and 13D, so that all the printed circuits are formed at the bent portion 24 and the opening edge 21 when the dent is drawn. Good quality can be maintained without cracks.

As described above, the embodiment has been described in which a total of four printed circuits including one common printed circuit and three single printed circuits are arranged. However, the present invention is not limited to this. In the case of a total of [N + 1] printed circuits including a common printed circuit and N (N is a positive integer) single printed circuits,
Circumferential length crossing bent portion 24 of depression 20 and depression 2
A printed circuit having an arc length that divides the circumference of the opening edge 21 of 0 into approximately [N + 1] may be used, and a total of three printed circuits including one common printed circuit and two single printed circuits In the case of the printed circuit described above, the printed circuit may have an arc length obtained by dividing the circumferential length of the recess 20 across the bent portion 24 and the circumferential length of the recess 20 across the opening edge 21 into approximately three equal parts. In the case of a total of two printed circuits including one common printed circuit and one single printed circuit, the circumferential length of the bent portion 24 of the recess 20 and the circumferential length of the opening edge 21 of the recess 20 are substantially equal. The printed circuit may be divided into two equal parts.

[0027]

As described above, one common printed circuit and N (N is a positive integer) single printed circuits which are paired with the common circuit and are used only one at a time are used. A metal core printed circuit board with a recess, characterized in that the arc lengths crossing the bent portion of the recess are equal and the arc lengths across the opening edge of the recess are equal, and a certification tool using the circuit board can be provided. Therefore, the width dimension of N (N is a positive integer) single printed circuits can be increased, and cracks are formed in each printed circuit at the bent portion of the dent and the opening edge when the dent is drawn. This prevents the occurrence of defects such as poor contact, and produces an effect of not causing defects.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part showing an example of a metal core printed circuit board with a depression according to the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a view for explaining the length of an arc that the printed circuit of FIG. 1 crosses over each part of the depression.

FIG. 4 is a plan view of an essential part showing an example of a certifying tool using the metal core printed circuit board with depressions of FIG. 1;

FIG. 5 is a sectional view taken along the line BB of FIG. 4;

FIG. 6 is a plan view of an essential part showing an example of a conventional metal core printed circuit board with a depression.

FIG. 7 is a sectional view taken along line CC of FIG. 6;

FIG. 8 is a view for explaining an arc length of the printed circuit of FIG. 6 crossing each part of the depression.

FIG. 9 is a plan view of a principal part showing an example of a certifier using the metal core printed circuit board with depressions of FIG. 6;

FIG. 10 is a sectional view taken along line DD of FIG. 9;

DESCRIPTION OF SYMBOLS 10 Metal core printed circuit board with depression 11 Metal core 12 Insulating layer 13A Common printed circuit 13B, 13C, 13D Single printed circuit 20 Depression 21 Opening edge 22 Bottom surface 23 Inclined wall surface 24 Bending portion 50 Lighting device 51, 52 , 53 light emitting diode chip 57 resin

Claims (4)

[Claims] 1. A recessed metal core printed circuit board formed by using a male type and a female type to form a recess having a concentric circular plane and a substantially inverted trapezoidal cross section. One common printed circuit and N (N is a positive integer) single printed circuits extending outside the recess through the wall surface and the opening edge of the recess are provided, and the one common printed circuit is provided. A metal core printed circuit board with depressions, wherein each of the circuit and each of the N single printed circuits has substantially the same arc length across the bent portion and the same arc length across the opening edge. 2. The printed circuit board according to claim 1, wherein the value of N is a positive integer of 3 or less. 3. A metal core printed circuit board having a recess formed by using a male type and a female type to form a recess having a concentric plane and a substantially inverted trapezoidal cross section, wherein at least a light emitting element is mounted on the bottom surface of the recess. A lighting device using a metal core printed circuit board with a dent formed by a common printed circuit extending out of the dent through a bent portion, an inclined wall surface, and an opening edge of the dent from the bottom of the dent; (N is a positive integer) single printed circuits, and the one common printed circuit and the N single printed circuits each have substantially the same arc length across the bent portion. A lighting device using a metal core printed circuit board with depressions, wherein arc lengths crossing the opening edge are substantially equal. 4. The lighting device according to claim 1, wherein the value of N is a positive integer of 3 or less.