JP4781961B2 - Electronic device and lighting apparatus - Google Patents

Description

  The present invention relates to an electronic device (particularly, a discharge lamp lighting device) and a lighting fixture.

In an electronic device such as a discharge lamp lighting device, it is publicly known that heat is radiated from a heat-generating electronic component (hereinafter referred to as “heat-generating component”) to a metal case (hereinafter referred to as “metal case” or simply “case”). It is. Moreover, the technique for improving the heat dissipation effect is known. In Patent Document 1, an insulating plate between the substrate on which the electronic component is mounted and the case is opened, and the heat radiating plate of the heat generating component is inserted through the opening of the insulating plate and fixed to the inner surface of the case. It is shown. Patent Document 2 discloses that grease is applied to the interface between the heat generating component and the case. Patent Document 3 discloses that in a case, a recess is formed in a region corresponding to a region where a heat generating component of a substrate is mounted, and the heat generating component is brought into direct contact with the bottom wall of the recess. Patent Document 4 discloses that a case is filled with a heat-dissipating resin having a thixotropic property.
Japanese Patent Laid-Open No. 04-62712 Japanese Utility Model Publication No. 06-60192 Japanese Patent Laid-Open No. 10-65385 Japanese Patent Laid-Open No. 2002-141676

  For example, as a heat generating component in a discharge lamp lighting device, there is a semiconductor switching element. The heat generated by the switching element prevents a stable switching operation. As a result, the stable operation of the discharge lamp is hindered. In addition, the usable temperature of the semiconductor is determined by the internal junction temperature of the semiconductor. If this temperature exceeds the usable temperature range, the component is destroyed. For this reason, it is necessary to radiate heat from the heat-generating component and suppress the temperature rise.

The conventional heat dissipation method was based on the following principle.
(1) Heat generation is due to power loss of parts.
(2) The power loss of the component in the steady use state is constant, and the heat generated from the component is dissipated to the surroundings.
(3) Heat is released from the component to the case by bringing the component into contact with the case.
(4) Since the case is in contact with the lighting fixture, heat is radiated from the entire case to the lighting fixture.
(5) Dissipate heat from the lighting equipment to the atmosphere.
(6) As a result, heat can be radiated from the component to the atmosphere, and the temperature rise of the component can be suppressed.

  As described above, heat is radiated from the parts through the case, the lighting fixture, and the atmosphere. Therefore, the point is how much heat generated from the parts can be conducted to the case when the form of the lighting fixture and the atmospheric condition are under certain conditions.

  In the prior art, when the heat generating component and the case are brought into contact with each other, there is a problem that a sufficient area of the contact surface cannot be obtained and the heat radiation amount from the heat generating component to the case is small. In addition, when a member such as grease or filler (thixotropic resin) is interposed between the heat generating component and the case, the member is very soft, so a large number of members are used to connect the heat generating component and the case. There is a problem that the weight and cost of the apparatus are large (even if the member is cured after mounting, the same problem remains). Moreover, since the shape of the member is not constant, there is a problem that the design is not easy.

  An object of the present invention is to enhance the heat radiation effect from a heat generating component to a metal case in an electronic device, and to reduce the effort and cost of designing and mounting the electronic device.

An electronic device according to one aspect of the present invention includes:
A circuit board on which at least one heat-generating electronic component is surface-mounted,
A metal case for housing the circuit board;
And a heat dissipating member arranged to thermally connect the electrode part of the electronic component and the case.

  According to one aspect of the present invention, a circuit board on which at least one heat generating component is surface-mounted, a metal case that accommodates the circuit board, and an electrode portion of the heat generating component and the metal case are thermally connected. By providing the heat dissipating member arranged in this manner, the heat dissipating effect from the heat generating component to the metal case in the electronic device is enhanced, and the effort and cost of designing and mounting the electronic device can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, a discharge lamp lighting device will be described as the electronic device according to each embodiment, but other electronic devices can be implemented in the same manner as long as they include a heat generating component and a metal case.

Embodiment 1 FIG.
FIG. 1A is an exploded perspective view of the discharge lamp lighting device 100 according to the present embodiment as viewed obliquely from above. Moreover, FIG.1 (b) is the disassembled perspective view which looked at the discharge lamp lighting device 100 in this Embodiment from diagonally downward.

  As shown in FIG. 1, the discharge lamp lighting device 100 includes a substrate 101, an insulating plate 102, and a metal case 103.

  The discharge lamp lighting device 100 is installed in a lighting fixture (not shown). In addition to the discharge lamp lighting device 100, the lighting fixture includes a lighting fixture body having at least a discharge lamp (lamp). In the discharge lamp lighting device 100, a discharge lamp lighting circuit for lighting the discharge lamp is mounted on the substrate 101. The insulating plate 102 is disposed along the inner peripheral surface of the metal case 103 that houses the substrate 101, and maintains insulation between the substrate 101 and the metal case 103.

  A plurality of components 104a to 104c (electronic components) are mounted on the substrate 101 by the pin insertion method (that is, they are mounted through holes) on the substrate 101. A surface of the substrate 101 on which the components 104a to 104c are mounted is referred to as a component surface 105. On the back side of the component surface 105, surface mount type heat generating components 106a and 106b are mounted (that is, surface mounted). A surface of the substrate 101 on which the heat generating components 106a and 106b are mounted is referred to as a solder surface 107. A heat radiating material 108 is provided on the solder surface 107.

  FIG. 2A is a partially enlarged view of the substrate 101 of the discharge lamp lighting device 100. FIG. 2B is a cross-sectional view of the discharge lamp lighting device 100 taken along line AA.

  As shown in FIG. 2, the heat generating components 106 a and 106 b are switching elements such as MOSFETs (metal oxide semiconductor field effect transistors) that form part of the discharge lamp lighting circuit. The electrodes 109a-b protrude so that the legs 110a-b protrude from the opposite side surface. A detailed configuration of the heat generating component 106 in this example is shown in FIG.

  FIG. 3A is a conceptual plan view of the heat generating component 106. FIG. 3B is a conceptual side view of the heat generating component 106.

  As shown in FIG. 3, the heat generating component 106 includes a semiconductor chip 111, a lead frame 112, a bonding wire 113, a lead terminal 114, and a mold resin 115. For example, the semiconductor chip 111 is soldered to a copper lead frame 112. As described above, the portion of the lead frame 112 that protrudes from the side surface of the mold resin 115 is called an electrode 109. Further, the semiconductor chip 111 is connected to two lead terminals 114 made of copper by, for example, an aluminum bonding wire 113. As described above, the portion of the lead terminal 114 that protrudes from the side surface of the mold resin 115 (the side surface opposite to the side surface from which the electrode 109 protrudes) is referred to as the leg 110. When the heat generating component 106 is a MOSFET, for example, the electrode 109 is a drain terminal, one of the two legs 110 is a source terminal, and the other is a gate terminal.

  Hereinafter, only the heat generating component 106a will be described, and since the heat generating component 106b is the same as the heat generating component 106a, description thereof will be omitted.

  The electrodes 109 a and the legs 110 a of the heat generating component 106 a are both soldered to the solder surface 107 of the substrate 101. The portion where the electrode 109a is soldered, that is, the electrode 109a and the surrounding solder are combined and referred to as an electrode portion of the heat generating component 106a. Further, a portion to which the leg 110a is soldered, that is, the leg 110a and the solder around the portion are referred to as a leg portion of the heat generating component 106a. In each figure, solder is omitted.

  As shown in FIG. 2, the heat dissipating material 108 is, for example, a rubber-based member formed as a rectangular parallelepiped with silicon resin or acrylic resin, and an electrode portion (electrode 109a and solder around it) of the heat generating component 106a and a metal case 103 is disposed on the substrate 101 so as to be thermally connected. Specifically, the heat dissipation material 108 is disposed on the solder surface 107 of the substrate 101 so that one side surface thereof is in contact with the electrode portion of the heat generating component 106 a and the upper surface is in contact with the insulating plate 102. The heat generated from the electrode portion of the heat generating component 106a is conducted from the contact surface (that is, the side surface) with the electrode portion to the metal case 103 via the contact surface (that is, the upper surface) with the insulating plate 102.

  As described above, the discharge lamp lighting device 100 (electronic device) includes the substrate 101 (circuit board) on which the heat generating component 106a (at least one heat generating electronic component) is surface-mounted, and the metal case that houses the substrate 101. 103 (metal case) and a heat dissipating material 108 (heat dissipating member) disposed so as to thermally connect the electrode portion of the heat generating component 106a and the metal case 103. Thereby, the heat radiation effect from the heat generating component 106a in the discharge lamp lighting device 100 to the metal case 103 is enhanced, and the time and effort for designing and mounting the discharge lamp lighting device 100 can be reduced.

  The discharge lamp lighting device 100 further includes an insulating plate 102 (insulating member) disposed so as to electrically insulate the substrate 101 and the metal case 103, and the heat radiating material 108 includes a heat generating component 106a. The heat generated from the electrode portions is arranged to be conducted to the metal case 103 through the insulating plate 102. Thereby, both heat radiation from the heat generating component 106a to the metal case 103 and insulation can be achieved.

  The heat dissipating material 108 is shaped to be a polyhedron such as a rectangular parallelepiped, and conducts heat generated from the electrode portion of the heat generating component 106a from at least one surface to the case through one or more other surfaces. It is arranged like this. This facilitates mounting and processing of the heat dissipation material 108.

  The heat dissipating material 108 is formed so that the height of the upper surface is higher than the upper end of the heat generating component 106, and heat generated from the electrode portion of the heat generating component 106a is conducted to the metal case 103 through the upper surface. It is arranged. Thereby, when the board | substrate 101 is pressed in the metal case 103, since the thermal radiation material 108 buffers, the design and mounting of the discharge lamp lighting device 100 become easy.

  It is desirable that the electrode portion of the heat generating component 106 a be disposed in the vicinity of the metal case 103. The closer the distance between the electrode portion of the heat generating component 106a and the metal case 103 is, the smaller the size of the heat dissipation material 108 can be made.

  The heat dissipating material 108 may be disposed such that not only the upper surface thereof but also one or more side surfaces other than the contact surface with the electrode portion of the heat generating component 106 a are in contact with the insulating plate 102.

  In this case, the heat dissipating material 108 is disposed so as to conduct the heat generated from the electrode portion of the heat generating component 106a to the metal case 103 from at least one surface through the other two or more surfaces. Thereby, the heat dissipation effect by the heat dissipation material 108 is further enhanced.

  The heat dissipating material 108 may be disposed so that the bottom surface thereof contacts the solder surface 107 of the substrate 101. At this time, even if the position of the heat dissipation material 108 on the solder surface 107 overlaps with the position where at least one of the terminals of the components 104 a to 104 c mounted on the component surface 105 of the substrate 101 protrudes on the solder surface 107. Good. A portion where the terminal is soldered, that is, the terminal and the solder around the terminal are referred to as a terminal portion. When the heat dissipation material 108 is in contact with the terminal portion, the heat generated from the terminal portion can be conducted to the metal case 103. That is, in this case, it is possible to radiate heat from both the electrode portion of the heat generating component 106a and at least one of the terminal portions of the components 104a to 104c using one heat radiating material 108.

  Since both the electrode 109a and the leg 110a are actually “electrodes”, the heat dissipating material 108 is composed of a leg portion of the heat generating component 106a (the leg 110a and solder around it) instead of the electrode portion of the heat generating component 106a. The metal case 103 may be thermally connected. However, it is easier to mount the heat dissipating material 108 on the electrode part side of the heat generating component 106a because the heat dissipating material 108 having a simple shape such as a rectangular parallelepiped can be used. And since a contact area becomes large, the thermal radiation effect improves. In addition, as described above, when the electrode 109 is a drain terminal and the leg 110 is a source terminal and a gate terminal, the amount of heat generated from the electrode 109 is considered to be the highest, so that heat is radiated to the electrode portion side of the heat generating component 106a. It is advantageous to provide the material 108.

  Further, as the heat dissipating material 108, both the one that thermally connects the electrode portion of the heat generating component 106a and the metal case 103 and the one that thermally connects the leg portion of the heat generating component 106a and the metal case 103 are arranged on the substrate 101. May be provided. Alternatively, one heat dissipating material 108 is formed so as to thermally connect the electrode portion of the heat generating component 106 a and the metal case 103 and to thermally connect the leg portion of the heat generating component 106 a and the metal case 103. Also good.

  The heat dissipation material 108 preferably has a hardness of 20 to 70 based on the test method of JIS-K-6250. For example, it has been experimentally confirmed that a heat dissipation material 108 made of silicon resin having a hardness of about 40 is disposed on the substrate 101 and the contact area can be increased when the substrate 101 is pressed into the metal case 103. ing.

  Thus, the heat dissipation material 108 is an elastic solid member formed of silicon resin or acrylic resin. This facilitates the design, processing, weight reduction, and cost reduction of the heat radiating member as compared with the case where heat is radiated from the heat generating component 106a using a filler formed of urethane resin or the like.

  Hereinafter, the heat dissipation effect from the heat generating component 106a to the metal case 103 will be compared between the case where the heat dissipation material 108 is not used and the case where the heat dissipation material 108 is used. Here, the configuration of the heat generating component 106a is the same as that of the heat generating component 106 shown in FIG. When the heat dissipation material 108 is not used, it is assumed that the mold resin 115 of the heat generating component 106 is in contact with the insulating plate 102.

First, a heat conduction formula representing a heat radiation amount when heat is radiated from the semiconductor chip 111 of the heat generating component 106a to the metal case 103 via some substance is shown as Expression (1).
Q = λ · (S / T) × (θi−θj) (1)
(Where Q: calorie, λ: thermal conductivity, S: area, T: distance, θi: heat source temperature, θj: heat dissipation temperature)

  Q is determined by the power loss of the heat generating component 106a. λ is a value specific to the substance. S is the area of the heat dissipation surface. When the heat dissipating material 108 is not used, S is the contact area of the heat generating component 106a with the insulating plate 102. When using the heat dissipation material 108, S is the contact area of the heat dissipation material 108 with the insulating plate 102. T is the distance from the heat dissipation surface to the metal case 103. When the heat dissipating material 108 is not used, T is the distance from the contact surface of the heat generating component 106a with the insulating plate 102 to the metal case 103. When using the heat dissipation material 108, T is the distance from the contact surface of the heat dissipation material 108 with the insulating plate 102 to the metal case 103.

  The higher the thermal conductivity of the insulating plate 102, that is, the larger the λ, the greater the heat dissipation amount Q. The wider the contact surface of the heat generating component 106a with the insulating plate 102, that is, the greater the S, the greater the heat dissipation amount Q. The thinner the insulating plate 102, that is, the smaller the T, the greater the heat dissipation amount Q.

  When the heat radiating material 108 is not used and when the heat radiating material 108 is used, the above materials are different, and thus the thermal conductivity λ is different. When the heat dissipation material 108 is not used, the mold resin 115 corresponds to the above substance. The thermal conductivity of the mold resin 115 is about 0.2 W / (m · K). On the other hand, when the heat dissipation material 108 is used, the lead frame 112, a metal such as solder, and the heat dissipation material 108 correspond to the above substances. The thermal conductivity of the metal is several hundred W / (m · K), and the thermal conductivity of the heat dissipation material 108 is several tens of W / (m · K). Therefore, if the temperature of the internal junction of the heat generating component 106a and the temperature of the electrode part are substantially the same, the heat radiated from the electrode part using the heat radiating material 108 is about 50 times higher than the heat radiated from the mold resin 115. There will be an effect. Further, the contact surface between the mold resin 115 and the insulating plate 102 has fine irregularities, and a portion that is not actually in contact is large. On the other hand, since the heat dissipating material 108 is an elastic (soft) member, the area of contact with the insulating plate 102 can be efficiently taken. Therefore, using the heat dissipating material 108 further increases the heat dissipating effect.

In the experiment, under the same conditions, (A) when the heat dissipation material 108 is not used, (B) when the heat dissipation material 108 is provided in contact with the mold resin 115 and the insulating plate 102, (C) the electrode portion and the insulating plate 102 The heat source temperature θi was measured for each of the cases where the heat dissipating material 108 was provided so as to be in contact with. as a result,
In the case of (A): θi = 91.0 ° C.
In the case of (B): θi = 84.3 ° C.
In the case of (C): θi = 79.2 ° C.
(C) It was confirmed that when the heat dissipating material 108 was provided in contact with the electrode portion and the insulating plate 102, the heat dissipating effect was the highest.

The metal case 103 is in contact with the luminaire main body, and further conducts heat conducted from the heat generating component 106a to the luminaire main body. And the lighting fixture main body radiates heat to the atmosphere. For reference, the heat conduction equation representing the heat radiation amount in this case is shown as equation (2).
Q = α · S × (θi−θj) (2)
(Where Q: calorie, α: thermal conductivity, S: surface area, θi: heat source temperature, θj: heat radiation destination temperature)

α is about 5 to 10 kcal / m ² hr ° C. in the case of windless air. S is the contact area of the luminaire main body with the atmosphere, that is, the surface area of the luminaire main body. Since the luminaire main body is attached to the ceiling, heat is radiated from the luminaire main body to the ceiling as well, but the heat radiation amount can be expressed by the above formula (1). At that time, the contact area of the lighting fixture body with the ceiling is S, and the thickness of the ceiling is T.

Embodiment 2. FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  FIG. 4A is a partially enlarged view of the substrate 101 of the discharge lamp lighting device 100 in the present embodiment. FIG. 4B is a cross-sectional view of the discharge lamp lighting device 100 taken along the line AA.

  In FIG. 4, the main difference from FIG. 2 described in the first embodiment is that the heat generating component 106 a and the heat radiating member 108 have the same height.

  The heat generating component 106a is mounted on the solder surface 107 of the substrate 101 so that the upper surface of the heat generating component 106a is in contact with the insulating plate 102, and heat generated from the inside of the heat generating component 106a is exchanged with the insulating plate 102. Conductive directly from the contact surface (that is, the upper surface) to the metal case 103. That is, the resin mold surface of the heat generating component 106 a is also thermally connected via the metal case 103 and the insulating plate 102, similarly to the heat dissipation material 108.

  Thus, the heat dissipation material 108 is formed so that the height of the upper surface is the same as the upper end of the heat generating component 106a, and heat generated from the electrode portion (the electrode 109a and the solder around it) of the heat generating component 106a is transferred to the upper surface. It is arrange | positioned so that it may conduct to the metal case 103 via. The heat generating component 106a is disposed so as to conduct heat generated from the inside to the metal case 103 via the upper end. Thereby, the heat dissipation effect is further enhanced.

  The heat dissipating material 108 may be disposed such that not only the upper surface thereof but also one or more side surfaces other than the contact surface with the electrode portion of the heat generating component 106 a are in contact with the insulating plate 102. Alternatively, instead of the upper surface, one or more side surfaces other than the contact surface with the electrode portion of the heat generating component 106a may be disposed so as to contact the insulating plate 102. At this time, the heat dissipating material 108 may be formed so that the height thereof is lower than that of the heat generating component 106a.

  In this case, the heat dissipating material 108 is formed so that the height of the upper surface is the same as or lower than the upper end of the heat generating component 106a, and heat generated from the electrode portion of the heat generating component 106a is transferred to the metal case 103 via the side surface. It is arrange | positioned so that it may conduct to. The heat generating component 106a is disposed so as to conduct heat generated from the inside to the metal case 103 via the upper end. Thereby, the heat dissipation effect is further enhanced.

Embodiment 3 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  Fig.5 (a) is the elements on larger scale of the insulating board 102 of the discharge lamp lighting device 100 in this Embodiment. FIG. 5B is a cross-sectional view of the discharge lamp lighting device 100.

  As shown in FIG. 5A, the insulating plate 102 is provided with an opening 116. The size of the opening 116 may be larger than the outer shape of the heat dissipation material 108. In consideration of the insulating property of the insulating plate 102, the size of the opening 116 is preferably the same as or slightly larger than the outer shape of the heat dissipation material 108.

  5B, the main difference from FIG. 2B described in the first embodiment is that the heat dissipating material 108 penetrates the insulating plate 102 and contacts the metal case 103. FIG.

  As described above, the insulating plate 102 has the opening 116 through which the heat dissipating material 108 passes so that the heat dissipating material 108 contacts the metal case 103. The heat dissipating material 108 is disposed so as to be in contact with the electrode portion (the electrode 109 a and the solder around it) of the heat generating component 106 a and the metal case 103. Thereby, since the influence of the insulating plate 102 on the heat radiation by the heat radiating material 108 is eliminated (the heat radiating material 108 has higher thermal conductivity than the insulating plate 102), the heat radiating effect by the heat radiating material 108 is further enhanced.

  The opening 116 may be formed in a size that allows not only the heat dissipation material 108 but also the heat generating component 106a to pass therethrough. As a result, the heat generating component 106 a can also be mounted so that the upper surface thereof is in contact with the metal case 103 in the same manner as the heat dissipating material 108.

Embodiment 4 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  FIG. 6 is a partial enlarged view of the substrate 101 of the discharge lamp lighting device 100 in the present embodiment.

  6, the main difference from FIG. 2A described in the first embodiment is that one heat dissipating material 108 is formed by the electrode portions (electrodes 109a to 109b) of both the heat generating component 106a and the heat generating component 106b. The surrounding solder) is formed to be thermally connected to the metal case 103.

  When the plurality of heat generating components 106a and 106b are installed in the vicinity, heat can be radiated from the respective electrode portions to the metal case 103 using only one heat radiating material 108. If the positions of the heat generating component 106a and the heat generating component 106b are not aligned, the heat dissipating material 108 is processed into a shape that matches the position shift, or the heat dissipating material 108 is pressed with pressure in a portion where there is a position shift. Can be dealt with.

  As described above, the heat generating components 106a and 106b (two or more heat generating electronic components) are surface-mounted on the substrate 101, and the heat dissipation material 108 includes the heat generating components 106a and 106b (of which at least two electronic components are included). ) And the metal case 103 are thermally connected. Thereby, the effort of mounting the discharge lamp lighting device 100 can be reduced.

Embodiment 5 FIG.
In the present embodiment, differences from the first embodiment will be mainly described.

  FIG. 7A is a partially enlarged view of the substrate 101 of the discharge lamp lighting device 100 in the present embodiment. FIG. 7B is a cross-sectional view taken along line AA of the discharge lamp lighting device 100.

  In FIG. 7, the main difference from FIG. 2 described in the first embodiment is that a cushioning material 117 is provided on the upper surface of the heat generating component 106a.

  The buffer material 117 may be a member made of a material different from that of the heat radiating material 108 such as grease, but it is desirable that the buffer material 117 is a rubber-based member formed of silicon resin or acrylic resin, like the heat radiating material 108. .

  As described above, the discharge lamp lighting device 100 is further provided with a buffer disposed so as to thermally connect at least a part of the heat generating component 106a other than the electrode portion (the electrode 109a and solder around the electrode 109a) and the metal case 103. A material 117 (buffer member) is provided. Thereby, not only the heat dissipation effect is enhanced, but also a noise suppression effect and an insulation effect that cannot be achieved by the thin insulating plate 102 alone are exhibited.

Embodiment 6 FIG.
The difference between the present embodiment and the second embodiment will be mainly described.

  FIG. 8A is a partially enlarged view of the inside of the metal case 103 of the discharge lamp lighting device 100 in the present embodiment. FIG. 8B is a cross-sectional view of the discharge lamp lighting device 100.

  As shown in FIG. 8A, the metal case 103 is provided with an embossed portion 118.

  In FIG. 8B, the main difference from FIG. 4B described in the second embodiment is that the position of the upper surface of the heat dissipation material 108 is lower than the height of the metal case 103, and the position of the upper surface of the heat dissipation material 108. In other words, the metal case 103 is partially recessed.

  As described above, the metal case 103 has a part of the surface facing the upper surface of the heat dissipation material 108 in contact with the upper surface of the heat dissipation material 108 or a part of the surface facing the upper surface of the heat dissipation material 108 than the other part. It is shaped so as to approach the upper surface of the heat dissipation material 108. Thereby, since the thermal radiation material 108 can be made thin, the cost of mounting the discharge lamp lighting device 100 can be suppressed.

  In FIG. 8B, the distance between the heat generating component 106a and the metal case 103 is shortened by the embossing as well as the heat dissipation material 108. That is, the metal case 103 is formed so that the portion of the metal case 103 with which the heat radiating material 108 comes into contact approaches the heat generating component 106a. Here, the heat dissipating material 108 is disposed such that one or more side surfaces other than the contact surface with the electrode portion (the electrode 109a and the solder around it) are in contact with the insulating plate 102 instead of the upper surface. May be.

  As described above, the metal case 103 has a part of the surface facing the upper end of the heat generating component 106a in contact with the upper end of the heat generating component 106a, or a part of the surface facing the upper end of the heat generating component 106a than the other part. It is shaped so as to approach the upper end of the electronic component. Thereby, since the distance T of the above-described formula (1) can be reduced, further heat dissipation is possible.

Embodiment 7 FIG.
The difference between the present embodiment and the second embodiment will be mainly described.

  The right side of FIG. 9 is a cross-sectional view of discharge lamp lighting device 100 in the present embodiment. The left side of FIG. 9 is the same as FIG. 4B described in the first embodiment.

  The main difference from the left side of the right side of FIG. 9 is that the heat generating component 106a and the heat radiating material 108 are thin and the metal case 103 is short.

  For example, when a general large component is used as the left heating component 106a, the thickness is about 4.5 mm, but when a general thin component is used as the right heating component 106a, the thickness is About 2.5 mm. Thus, by shortening the distance between the substrate 101 and the metal case 103, the heat dissipating material 108 can be made thin as in the sixth embodiment, so that the cost of mounting the discharge lamp lighting device 100 can be reduced. It is done. Further, since the distance T in the above-described formula (1) can be reduced, further heat dissipation is possible.

  As mentioned above, although embodiment of this invention was described, you may implement combining 2 or more embodiment among these. Alternatively, one of these embodiments may be partially implemented. Or you may implement combining two or more embodiment among these partially.

1 is an exploded perspective view of a discharge lamp lighting device according to Embodiment 1. FIG. It is the elements on larger scale and sectional drawing of the discharge lamp lighting device in Embodiment 1. FIG. FIG. 3 is a conceptual plan view and a side conceptual diagram of a heat generating component in Embodiment 1. It is the elements on larger scale and sectional drawing of the discharge lamp lighting device in Embodiment 2. FIG. It is the elements on larger scale and sectional drawing of the discharge lamp lighting device in Embodiment 3. FIG. It is the elements on larger scale of the discharge lamp lighting device in Embodiment 4. It is the elements on larger scale and sectional drawing of the discharge lamp lighting device in Embodiment 5. It is the elements on larger scale and sectional drawing of the discharge lamp lighting device in Embodiment 6. FIG. 10 is a cross-sectional view of a discharge lamp lighting device in a seventh embodiment.

Explanation of symbols

  100 discharge lamp lighting device, 101 substrate, 102 insulating plate, 103 metal case, 104 component, 105 component surface, 106 heat generating component, 107 solder surface, 108 heat dissipation material, 109 electrode, 110 leg, 111 semiconductor chip, 112 lead frame, 113 Bonding wire, 114 Lead terminal, 115 Mold resin, 116 Opening part, 117 Buffer material, 118 Embossed part.

Claims (10)

A component surface on which the electronic component is mounted and a surface on the back side of the component surface, and the terminal of the electronic component mounted on the component surface protrudes, and the protruding terminal is soldered , an electronic component with heat build-up at least 1 is surface-mounted, and a circuit board having a solder surface electrode of the electronic component being surface-mounted is soldered,
A metal case for housing the circuit board;
On the solder surface, terminals of electronic components mounted through holes on the component surface and terminal portions made of solder around the terminals , electrodes of electronic components surface-mounted on the solder surface and solder around the terminals. In contact with the electrode portion, both the terminal portion of the electronic component that is through-hole mounted on the component surface and the electrode portion of the electronic component surface-mounted on the solder surface are thermally connected to the case. An electronic device comprising: a heat dissipating member arranged to do so. The heat radiation member further electronic device according to claim 1, characterized in that it is arranged to contact the case. The heat radiating member is formed to be a polyhedron, and heat generated from an electrode portion of an electronic component surface-mounted on the solder surface is transmitted from at least one surface to one or more other surfaces. The electronic device according to claim 1, wherein the electronic device is disposed so as to be conductive. The heat dissipating member is disposed so as to conduct heat generated from the electrode portion of the electronic component surface-mounted on the solder surface from the at least one surface to the case via the other two or more surfaces. The electronic device according to claim 3. The heat dissipation member is shaped so that the height of the upper surface is the same or lower than the upper end of the electronic components are surface-mounted on the solder surface, the electrode portions of the electronic components are surface-mounted on the solder surface The heat generated from the heat radiating member is arranged to be conducted to the case through the side surface,
Electronic components are surface-mounted on the solder surface, characterized in that the heat generated inside, is arranged to conduct the case through the upper end of the electronic components are surface-mounted on the solder surface The electronic device according to claim 3 or 4. The case is to be in contact with the upper end of the electronic component portion of the surface facing the upper end of the electronic components are surface-mounted on the solder surface is surface-mounted on the solder surface, or a surface on the solder surface according to claim 5, characterized in that the portion of the surface facing the upper end of the electronic components mounted is shaped to approach the upper end of the electronic components are surface-mounted on the solder surface than other portions Electronic devices. The heat dissipation member is shaped so that the height of the upper surface is the same or above the upper end of the electronic components are surface-mounted on the solder surface, the electrode portions of the electronic components are surface-mounted on the solder surface The electronic device according to claim 3, wherein the electronic device is disposed so as to conduct heat generated from the case to the case through an upper surface.   In the case, a part of the surface facing the upper surface of the heat radiating member is in contact with the upper surface of the heat radiating member, or a part of the surface facing the upper surface of the heat radiating member is higher than the upper surface of the heat radiating member. The electronic device according to claim 7, wherein the electronic device is shaped so as to approach the head. The electronic device further includes:
An insulating member disposed to electrically insulate the circuit board and the case;
The electronic device according to claim 1, wherein the insulating member has an opening through which the heat radiating member penetrates so that the heat radiating member contacts the case. A luminaire body having a lamp;
As electronic components of the exothermic, characterized in that it comprises an electronic device according to any one of the lamp the claims 1 electronic component that is surface-mounted on the circuit board solder surface for lighting up 9 Lighting equipment.