JP4277593B2 - Electronic device having a shield jacket - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic device having a shield jacket, and is used, for example, for housing a printed board on which a lighting circuit for lighting a fluorescent lamp or a high-intensity discharge lamp is mounted.
[0002]
[Prior art]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-105921 [Patent Document 2]
Japanese Patent Laid-Open No. 2002-367321
In recent years, digitization of discharge lamp lighting devices such as fluorescent lamps and high-intensity discharge lamps (HID lamps) used for lighting in commercial facilities and offices has been progressing. In addition, it is desired to reduce the size and price of lighting fixtures.
[0004]
FIG. 11 shows an example of a mounting structure of a conventional discharge lamp lighting device. In the figure, 61 is a metal lid plate, 62 is a metal bottom plate, 63 is a resin insulating sheet, and 5 is a printed circuit board. FIG. 12 shows a cross-sectional structure taken along line AA ′. On the printed circuit board 5, electronic components of a discharge lamp lighting circuit are mounted. A plurality of terminal blocks 64 are provided at the end of the printed circuit board 5. A plurality of lead wires 65 are drawn from each terminal block 64. The metal lid plate 61 and the metal bottom plate 62 are formed by bending a metal plate by sheet metal processing. As the resin insulating sheet 63, for example, Lumirror (trade name) manufactured by Toray Industries, Inc. is used, and as shown in FIG. 12, a metal case in which a metal cover plate 61 and a metal bottom plate 62 are combined. The metal case and the charging part on the printed circuit board 5 are insulated from each other. In order to ensure the reliable insulation of the insulating sheet 63 at the portions corresponding to the three-dimensional ridgelines and corners, the insulating sheets 63 are folded over like a portion indicated by X in FIG. 12 (a circled portion). It was necessary to make such a structure. Therefore, there is a problem that the process of wrapping the printed circuit board 5 with the insulating sheet 63 that has been preliminarily attached and storing it in a metal case is required, and the workability at the time of manufacture is poor.
[0005]
FIG. 13 shows another example of the mounting structure of the conventional discharge lamp lighting device. FIG. 14 shows a cross-sectional structure taken along line BB ′. In the figure, 71 is a metal cover plate, 72 is a metal bottom plate, 73 is a resin filler, and 5 is a printed circuit board. The metal lid plate 71 and the metal bottom plate 72 are formed by bending a metal plate by sheet metal processing. On the printed circuit board 5, electronic components of a discharge lamp lighting circuit are mounted. Spacers 78 and 79 are disposed between the printed circuit board 5 and the metal bottom plate 72. The resin filler 73 is made of, for example, urethane resin and is filled in a space between the printed board 5 and the metal bottom plate 72 to insulate the metal case from the charging part on the printed board 5. An input / output lead wire 75 is drawn from a metal case in which a metal lid plate 71 and a metal bottom plate 72 are combined. A bushing 76 for preventing insulation failure due to damage to the coating of the lead wire due to rubbing between the metal case and the lead wire needs to be separately prepared in the lead portion of each lead wire. For this reason, there existed a subject that component cost became high and workability | operativity at the time of manufacture was bad.
[0006]
FIG. 15 shows still another example of the mounting structure of the conventional discharge lamp lighting device. FIG. 16 shows a cross-sectional structure taken along the line CC ′. In the figure, 81 is a metal case made of extruded aluminum, 82 is an aluminum heat sink made of extruded aluminum, 86 and 87 are side ends formed by sheet metal processing, 5 is a printed circuit board, 84 is a connector, and 85 is a lead. Is a line.
[0007]
The above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 7-105921) discloses a battery pack mounting structure, and Patent Document 2 (Japanese Patent Application Laid-Open No. 2002-367321) discloses a disk cartridge mounting structure divided into two. It is disclosed that each half of the case is configured to be point-symmetric or line-symmetric.
[0008]
Moreover, the structure equivalent to the resin case shown in FIGS. 5-9 is proposed by our prior application (Japanese Patent Application No. 2002-373184). As a result, it was shown that the structure for protecting the lead wire can be provided at a low price while the charged portion of the printed circuit board is insulated, and the workability at the time of manufacture can be improved.
[0009]
[Problems to be solved by the invention]
However, in our previous application (Japanese Patent Application No. 2002-373184), it is necessary to strengthen the noise shielding performance of the discharge lamp lighting device alone and the strength of the mounting portion (see 21 and 22 in FIG. 5). There is. This depends on the shape, material, and the like of the lighting fixture incorporating the discharge lamp lighting device.
[0010]
Therefore, in order to solve the above problems, a structure having a metal case on the outer side of the resin case has been examined. However, since the metal case is configured by fitting each metal case half divided into two parts. Each case shape was different, and it was necessary to create a mold for each case half. As a result, a new problem has arisen that mold costs increase.
[0011]
The present invention has been made in view of the above points, and can improve the shield performance of noise, enhance the strength of the mounting portion, improve the workability at the time of manufacture, and suppress the investment in the mold. It is an object to realize an electronic device having a low price.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, according to the present invention, as shown in FIG. 1, a printed circuit board on which an electronic circuit is mounted, a resin insulating case 2 covering the printed circuit board, and an outer side of the insulating case 2 An electronic device having a metal shield jacket 1, 1 ′ disposed on the metal shield jacket 1, 1 ′ is a combination of two metal cases having substantially the same shape. Each of the two metal cases has a structure in which the inner surface touches at least five of the upper, lower, front, rear, and left and right surfaces of the insulating case 2.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 is a perspective view showing an external appearance of a resin case seen through an outer metal case in an electronic device of the present invention. In the figure, 1 and 1 'are metal cases, and 2 is a resin case. One metal case 1 is provided with an opening 10 corresponding to a lead wire drawing hole (2a, 2b, 2c, 2d, 2e in FIG. 5) of the resin case 2. The other metal case 1 ′ has the same shape as the metal case 1 except that it does not have an opening, and is configured to cover the resin case 2 from the side opposite to the metal case 1.
[0014]
FIG. 2 is a plan view showing the metal case 1 used as a shield jacket of the electronic device of the present invention in a flat shape. The metal case 1 is formed by punching a metal plate with a metal mold and bending it as shown in FIGS. The other metal case 1 ′ has the same configuration as the metal case 1 except that the opening 10 is not provided. Therefore, with respect to the presence / absence of the opening 10, “open” of the opening 10 is realized using the same mold. By preparing a “nested” structure in the mold, it is possible to create the same mold without significant cost increase. The opening 10 opens to a size that does not allow human fingers to enter.
[0015]
3A and 3B are views showing an external appearance of the metal case 1 used as a shield jacket of the electronic device according to the present invention by three-dimensional bending, wherein FIG. 3A is a plan view seen from above and FIG. 3B is a view seen from the front side. (C) is a bottom view seen from below, (d) is a left side view seen from the left side, and (e) is a right side view seen from the right side.
[0016]
Hereinafter, the configuration of the metal case 1 will be described with reference to the developed view of FIG. 2 and the assembly drawings of FIGS. 11 is a substantially rectangular top plate and has the largest surface area. The left side of the top plate 11 is bent downward at a substantially right angle to form an upper left half side plate 12, and the right side of the top plate 11 is bent downward at a substantially right angle to form an upper right half side plate 13. The long side on the back side of the top plate 11 is an open end. The long side on the front side of the top plate 11 is bent at a substantially right angle downward to form a front plate 14. The front plate 14 is provided with an opening 10 that cannot insert a human finger. The lower end of the front plate 14 is bent at a substantially right angle in the same direction as the top plate 11 to form an L-shaped bottom plate 15 and an I-shaped bottom plate 16. The left side of the L-shaped bottom plate 15 is bent upward at a substantially right angle to form a lower left half plate 17, and the right side of the I-shaped bottom plate 16 is bent upward at a substantially right angle to form a lower right half plate 18. Further, the L-shaped bottom plate 15 and the I-shaped bottom plate 16 are shaped so as to complement each other. As shown in FIG. 4, by combining with the other metal case 1 ′, the L-shaped bottom plates 15, 15 ′. And the I-type bottom plates 16 and 16 'are combined to cover the surface area of two top plates. In order to attach the metal case 1, 1 ′ to the resin case 2, the L-shaped bottom plate 15 and the I-shaped bottom plate 16 are provided with tongue sides 15 a, 15 b, 16 a.
[0017]
As described above, one metal case 1 has the opening 10 in the front plate 14, whereas the other metal case 1 ′ disposed on the back side of the resin case 2 is a front plate (back plate 14 ′). The only difference is that it does not have an opening. Reinforcing plates 15c of mounting portions 21 and 22 (see FIG. 10) for screwing the resin case 2 are provided at the end portions of the L-shaped bottom plate 15 of each metal case 1. The reinforcing plate 15c is provided with two U grooves 15d and 15e so as to open toward the front side and the left side, and is screwed so as to penetrate either of these U grooves 15d and 15e. The In order to form the U-grooved reinforcing plate 15c, the vicinity of the left end of the front plate 14 and the vicinity of the front surfaces of the left plates 12 and 17 are open portions. However, an inclined piece 14 a is provided in the vicinity of the left end of the front plate 14 to hold the vicinity of the front left end of the resin case 2. A notch 11a is also provided in the vicinity of the front left end of the top plate 11, and as can be seen from FIG. 3A, the workability when screwing from above with a screwdriver or the like is improved.
[0018]
Next, the configuration of the resin case 2 will be described. FIG. 5 is a perspective view of the resin case 2 as viewed obliquely from the front side. FIG. 6 is a perspective view of the upper half 3 of the resin case 2. FIG. 7 is a perspective view of the lower half 4 of the resin case 2. An attachment piece 31 is provided on the front side of the lower left side of the upper half 3 of the resin case 2, and an attachment piece 41 is provided on the front side of the lower left side of the lower half 4 of the resin case 2. And these are piled up and down, and the attachment part 21 is comprised. A U-groove for screwing that is opened to the left is formed in the mounting portion 21 so as to overlap the U-groove 15e described above. The attachment portion 21 is supported by the reinforcing plate 15 c of the metal case 1. An attachment piece 32 is provided on the upper half 3 of the resin case 2 and an attachment piece 42 is provided on the lower half 4 so that the other attachment portion 22 is formed on the back surface diagonally to the attachment portion 21. These are superposed one above the other to constitute the attachment portion 22. The mounting portion 22 is formed with a U-groove for screwing opened rearward so as to overlap the U-groove 15d ′ of the metal case 1 ′. The attachment portion 22 is supported by the reinforcing plate 15c ′ of the metal case 1 ′. (Although the development of the other metal case 1 ′ is not shown, the figure in which the opening 10 in FIG. 2 is deleted and “′” is attached to each symbol corresponds to the development of the metal case 1 ′. .)
[0019]
Returning to FIG. 6, the upper half 3 of the resin case 2 is provided with hook-like engagement pieces 33, 34 projecting downward, and the resin pieces 2, 34 are inserted to insert the engagement pieces 33, 34. In the lower half 4 of the case 2, as shown in FIG. 7, engagement holes 43 and 44 are opened upward. Similar engagement holes 45, 46 are opened upward on the back side facing the engagement holes 43, 44. Corresponding to these engagement holes 45, 46, a hook-like engagement piece (not shown) projects downward from the upper half 3 of the resin case 2.
[0020]
FIG. 8 is a cross-sectional view of the resin case 2. A printed circuit board 5 is accommodated between the upper half 3 and the lower half 4 of the resin case 2. Spacers 47, 48, and 49 are disposed below the printed circuit board 5, and support the printed circuit board 5 from below. The left and right ends of the printed circuit board 5 are pressed from above by the upper half 3 of the resin case 2 and fixed from both the upper and lower sides. On the printed circuit board 5, lighting circuits such as HID lamps and fluorescent lamps are constructed and mounted with electronic components, and lead wires are provided from the lead wire lead holes 2a, 2b, 2c, 2d, 2e (see FIG. 5). Pulled out.
[0021]
When assembling the resin case 2, the printed circuit board 5 on which an electronic circuit is mounted is placed on the spacers 47, 48, 49 of the lower half 4 of the resin case 2, and lead wire extraction holes 2 a, 2 b, 2 c, 2 d, 2e (see FIG. 5), with the lead wire pulled out, the upper half 3 of the resin case 2 is covered from above, and the hook-like engagement piece projecting downward from the upper half 3 is attached to the lower half. 4 is inserted into the engagement hole and engaged. Thereby, the charging part of an electronic circuit is insulated from the outside.
[0022]
FIG. 9 is a perspective view of the assembled resin case 2 as viewed obliquely from the back side. An elongated concave groove 40 is provided on the bottom surface of the resin case 2. In order to attach the above-described metal case 1, 1 ′ as the outer casing of the resin case 2, one of the metal cases 1 is inserted into the lead wire lead-out holes 2 a, 2 b, 2 c, 2 d, 2 e (see FIG. 5). The tongue 10a of the L-shaped bottom plate 15 of the metal case 1 and the tongue 16a of the I-shaped bottom plate 16 of the metal case 1 are bent and locked in the concave groove 40 on the bottom surface of the resin case 2 in correspondence with the opening 10. Since the other metal case 1 ′ has no opening in the front plate (back plate 14 ′), it is inserted from the opposite side of the lead wire lead-out holes 2a to 2e of the resin case 2, and as shown in FIG. The two metal cases 1, 1 'are combined so that the L-shaped bottom plates 15, 15' and the I-shaped bottom plates 16, 16 'complement each other. Then, the tongue piece 15b ′ of the L-shaped bottom plate 15 ′ of the metal case 1 ′ that does not have an opening on the front plate (back plate 14 ′) is bent and locked in the concave groove 40 on the bottom surface of the resin case 2.
[0023]
Thus, the resin case 2 can be covered by combining the pair of metal cases 1 and 1 ′ as shown in FIG. In the illustrated example, 80% or more of the surface area of the six surfaces of the resin case 2 is covered with the metal case 1, 1 ′. Finally, when incorporated in a lighting fixture, the effect of suppressing noise leaking from the discharge lamp lighting device can be expected by connecting the metal cases 1 and 1 'to the ground. Further, a discharge lamp lighting device can be used in a lighting fixture or the like by having a structure in which part of the metal cases 1 and 1 ′ (reinforcing plates 15c and 15c ′) is also embedded under the mounting portions 21 and 22 of the resin case 2. It is possible to prevent the attachment portions 21 and 22 from being damaged due to stress concentration or the like.
[0024]
Further, the insulation between the charging part of the printed circuit board 5 and the non-charging metal case 1, 1 'can be easily secured, and the workability at the time of assembly is good. Furthermore, since the heat conduction of the metal cases 1 and 1 'is good, the heat dissipation of the electronic circuit can be performed efficiently, so that the flame retardant level of the resin case 2 can be lowered and the material cost can be reduced.
[0025]
The plate thickness of the metal cases 1 and 1 ′ is made thinner than the average thickness of the resin case 2. Even in this case, the strength of the outer shell as a basic discharge lamp lighting device can be secured by the combination of the upper half 3 and the lower half 4 of the resin case 2.
[0026]
Further, in the illustrated embodiment, the two metal cases 1 and 1 ′ have no place where they are fitted to each other, so that there is no portion where the metal cases 1 and 1 ′ overlap vertically and horizontally or left and right. Therefore, the outer dimension of the electronic device can be limited to the increase in the thickness of the metal plate constituting the metal case 1, 1 ′ in the outer dimension of the resin case 2. For this reason, it can prevent that the dimension of an electronic device becomes large compared with the structure which requires the fitting of the metal case divided into two in the prior art example (refer to Drawing 12 and Drawing 14). This is a structure that can be realized by enclosing the resin case 2 having strength inside the metal cases 1 and 1 '. As in the conventional example of FIG. 12, the insulating sheet 63 having no strength ensures insulation. In such a structure, it is very difficult to adopt a structure in which the metal case is fixed without a fitting portion. Thus, by enclosing the resin case 2 having strength inside the metal cases 1 and 1 ′, it is possible to keep the increase in the external dimensions of the entire electronic device very slightly.
[0027]
The electronic device of the present invention can be used for, for example, an electronic ballast of an HID lamp, but is not limited to this, and it goes without saying that it can be widely applied to all electronic devices.
[0028]
【The invention's effect】
According to the first aspect of the present invention, since the periphery of the resin insulating case containing the printed circuit board is covered with the metal shield jacket, the charging part of the printed circuit board is removed from the metal shield by a simple operation at the time of manufacture. It can be insulated from the cover. In addition, the noise shielding performance can be improved and the strength of the mounting portion can be enhanced. As a result, a low-cost and highly reliable electronic device can be provided.
According to the first aspect of the present invention, since the metal shield jacket is composed of a combination of two metal cases having substantially the same shape, it can be manufactured with one mold, and metal cases with different shapes can be manufactured. The mold cost can be reduced as compared with the conventional example to be combined.
[0029]
According to the invention of claim 2 , by including a resin insulating case having strength inside the metallic shield jacket, the overlapping portion of the metallic shield jacket can be eliminated, and the electronic There is an effect that an increase in the external dimension of the entire apparatus can be kept extremely small.
According to the invention of claim 3 , the metal shield jacket has an opening portion that does not allow human fingers to enter, so that even if the lead wire is pulled out from this opening portion, a human hand is not in the charging portion. Safe without touching.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external appearance of a resin case seen through an outer metal case in an electronic device of the present invention.
FIG. 2 is a plan view showing a metal case used as a shield jacket of the electronic device of the present invention in a flat shape.
3A and 3B are views showing an external appearance of a metal case used as a shield jacket of an electronic device according to the present invention by three-dimensional bending, where FIG. 3A is a plan view seen from above, and FIG. 3B is a view seen from the front side. (C) is a bottom view seen from below, (d) is a left side view seen from the left side, and (e) is a right side view seen from the right side.
FIG. 4 is a bottom view of a state in which two metal cases of the electronic device of the present invention are combined, as viewed from below.
FIG. 5 is a perspective view of a resin case of the electronic device according to the present invention as viewed obliquely from the front side.
FIG. 6 is a perspective view of an upper half portion of a resin case of the electronic device of the present invention.
FIG. 7 is a perspective view of a lower half portion of a resin case of the electronic device of the present invention.
FIG. 8 is a cross-sectional view of a resin case of the electronic device of the present invention.
FIG. 9 is a perspective view of a resin case of the electronic device according to the present invention as viewed from diagonally below on the back side.
FIG. 10 is a perspective view showing a completed state of the electronic device of the invention.
11 is a perspective view of Conventional Example 1. FIG.
12 is a cross-sectional view of Conventional Example 1. FIG.
FIG. 13 is a perspective view of a second conventional example.
14 is a cross-sectional view of Conventional Example 2. FIG.
15 is a perspective view of Conventional Example 3. FIG.
16 is a cross-sectional view of Conventional Example 3. FIG.
[Explanation of symbols]
1 Metal case (with opening)
1 'metal case (no opening)
2 Resin case 10 Opening 21 Mounting part (front side)
22 Mounting part (rear side)

Claims (3)

An electronic apparatus comprising: a printed circuit board on which an electronic circuit is mounted; a resin insulating case that covers the printed circuit board; and a metal shield jacket disposed outside the insulating case, wherein the metal shield The outer cover is composed of a combination of two metal cases having substantially the same shape, and each of the two metal cases has an inner surface that touches at least five of the upper, lower, front, rear, and left and right surfaces of the insulating case. An electronic device having a shield jacket characterized by having a structure. The average thickness of the resin insulating case, an electronic apparatus having a shield casing according to claim 1, wherein a thicker than shield coat average thickness of the steel the metal. The metal shield sheath is an electronic device having a shield casing according to claim 1 or 2, characterized by having an opening degree that does not enter the human finger.

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