JPWO2013005404A1 - Heat sink, circuit board, and image display device - Google Patents

Abstract

A heat sink that can be attached to a circuit board more stably while suppressing an increase in costs and man-hours for manufacturing an image display device is realized. For this purpose, an opening and solder bonding areas provided on both sides of the opening are provided in the heat sink mounted on the circuit board. The heat sink has a shape that forms a ventilation tunnel in which the opening is surrounded by the circuit board and the heat sink and one end and the other end are opened when the solder bonding region is bonded to the circuit board. Have

Description

  The present invention relates to a heat sink mounted on a surface of a circuit board, a circuit board, and an image display device using them.

  The image display device has a housing having a front frame and a back cover. A chassis member to which an image display device and a drive circuit for driving the image display device are attached is housed inside the housing.

  A typical image display device is a plasma display panel. And the thickness of such an image display device is about several mm.

  However, even if the thickness of these image display devices is thin, the thickness of the image display device is determined by the size of electronic components and other components, the heat sink that must be provided to cope with the heat generated by the electronic components, etc. ing.

  For example, a plasma display device using a plasma display panel has a thickness of about 10 cm.

  A technique for thinning an image display device using an image display device has been proposed (see, for example, Patent Document 1). Patent Document 1 discloses a structure in which an insertion-type electronic component that generates heat during operation is attached to a heat sink having a special shape, and the heat sink is mounted on a circuit board together with the electronic component.

  The insertion-type electronic component is an electronic component that is mounted on the circuit board by inserting legs, leads, and the like of the electronic component into through holes provided in the circuit board.

  In order to further reduce the thickness of the image display device, the insertion type electronic component may be changed to a surface mounting type electronic component.

  The surface-mount type electronic component is an electronic component that is mounted on the surface of the circuit board without using a through hole by adhering to a mounting region provided on the surface of the circuit board with solder or the like. .

  However, for electronic components that generate heat during operation, it is necessary to attach a heat sink on the electronic components mounted on the surface of the circuit board. The heat radiating plate is attached to the electronic component using a member such as an adhesive tape, an adhesive, or a screw.

  However, the use of these members contributes to an increase in the cost for manufacturing the image display device. In addition, when manufacturing the image display device, man-hours for attaching the heat sink to the electronic component also occur. In addition, if adhesive tape is used to attach the heat sink to the electronic component, the number of man-hours can be reduced compared with the case where screws or adhesives are used, but the heat sink is removed when other operations are performed. Such a problem may occur.

  Therefore, there is a demand for a heat sink that can suppress an increase in costs and man-hours for manufacturing an image display device and can be more stably attached to a circuit board.

JP 2011-13596 A

  The present invention relates to a heat sink mounted on the surface of a circuit board, and the heat sink has the following shape. The heat radiating plate has an opening and solder bonding regions provided on both sides of the opening. And when this heat sink is bonded to the circuit board, the opening is surrounded by the circuit board and the heat sink, and one end and the other end are opened in the circuit. Form on the substrate.

  With this configuration, it is possible to realize a heat sink that can be attached to the circuit board more stably while suppressing an increase in costs and man-hours required for manufacturing the image display device.

  The present invention relates to a circuit board on which a heat sink and an electronic component are mounted. The circuit board has an opening and a solder bonding area provided on both sides of the opening. When the solder bonding area is bonded to the circuit board, the circuit board is surrounded by the heat sink and at one end. A heat sink that forms a ventilation tunnel having an opening at the other end on the circuit board is mounted at a predetermined distance from an electronic component that is radiated by the heat sink. And this circuit board is a heat sink that adheres the heat sink so that the line connecting the heat sink and the electronic component that is the target of heat dissipation intersects with the line drawn in the extending direction of the ventilation tunnel. Has an adhesive area.

  The area where the solder bonding area of the heat sink provided on the circuit board is bonded may be formed by arranging a plurality of areas having a rectangular shape extending in one direction in parallel.

  A plurality of regions for bonding the solder bonding regions of the heat sink may be provided on the circuit board so that the ventilation tunnels are in the same direction.

  The present invention relates to an image display device including an image display device, a drive circuit that drives the image display device, and a circuit board on which a heat sink is mounted. The heat radiating plate has an opening and solder bonding areas provided on both sides of the opening. When the solder bonding area is bonded to the circuit board, the opening is surrounded by the circuit board and the heat radiating plate. It has the shape which forms the ventilation tunnel which the edge part and the other edge part opened. The circuit board is mounted at a predetermined distance from the electronic components that are dissipated by the heat sink, and the line connecting the heat sink and the electronic components intersects the line drawn in the extension direction of the ventilation tunnel. A heat sink is arranged.

FIG. 1 is an exploded perspective view showing a structure of a panel used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 2 is an electrode array diagram of the panel used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 3 is a diagram schematically showing an example of a drive voltage waveform applied to each electrode of the panel used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 4 is a diagram schematically showing an example of a circuit block constituting the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 5 is a circuit diagram schematically showing a configuration example of the sustain pulse generating circuit used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 6 is a diagram schematically showing a part of a circuit board used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 7 is a diagram showing an example of an actual measurement value of the temperature of a circuit board on which electronic components that generate heat are mounted in the plasma display device according to the first exemplary embodiment of the present invention. FIG. 8 is a diagram showing an example of the shape of the heat sink used in the plasma display device in accordance with the first exemplary embodiment of the present invention. FIG. 9 is a perspective view showing an example of a region to which a heat sink provided on the circuit board in Embodiment 1 of the present invention is bonded. FIG. 10 is a perspective view showing an example of an arrangement position of the heat sink and electronic components mounted on the circuit board in the first embodiment of the present invention. FIG. 11 is a diagram showing an example of the shape of the heat sink used in the plasma display device in accordance with the second exemplary embodiment of the present invention. FIG. 12 is a front view showing an example of the shape of the heat sink in the third embodiment of the present invention. FIG. 13: is a front view which shows another example of the shape of the heat sink in Embodiment 3 of this invention. FIG. 14 is a front view showing an example of the shape of the heat sink in the fourth embodiment of the present invention. FIG. 15A is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention. FIG. 15B is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention. FIG. 15C is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention. FIG. 16A is a front view showing an example of the shape of the heat sink in Embodiment 5 of the present invention. FIG. 16B is a front view showing another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention. FIG. 16C is a front view showing still another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention. FIG. 16D is a front view showing still another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention.

  Hereinafter, a heat radiating plate, a circuit board, and an image display device using the same in an embodiment of the present invention will be described. Hereinafter, as an image display device, a plasma display device using, for example, a plasma display panel (hereinafter abbreviated as “panel”) will be described as an example and described with reference to the drawings.

(Embodiment 1)
FIG. 1 is an exploded perspective view showing the structure of panel 10 used in the plasma display device in accordance with the first exemplary embodiment of the present invention.

  The panel 10 is configured by arranging a glass front substrate 11 and a back substrate 21 to face each other.

  A plurality of display electrode pairs 14 including scan electrodes 12 and sustain electrodes 13 are formed on the front substrate 11. A dielectric layer 15 is formed so as to cover the scan electrode 12 and the sustain electrode 13, and a protective layer 16 is formed on the dielectric layer 15.

  The protective layer 16 is formed of a material mainly composed of magnesium oxide (MgO), which is a material having high electron emission performance, in order to easily generate discharge in the discharge cell.

  The protective layer 16 may be composed of one layer or may be composed of a plurality of layers. Moreover, the structure which particle | grains exist on a layer may be sufficient.

  A plurality of data electrodes 22 are formed on the back substrate 21, a dielectric layer 23 is formed so as to cover the data electrodes 22, and a grid-like partition wall 24 is formed on the dielectric layer 23. A phosphor layer 25 that emits light of each color of red (R), green (G), and blue (B) is provided on the side surface of the partition wall 24 and the dielectric layer 23.

  The front substrate 11 and the rear substrate 21 are arranged to face each other so that the display electrode pair 14 and the data electrode 22 intersect with each other across a minute discharge space, and a discharge space is formed in the gap between the front substrate 11 and the rear substrate 21. Is provided. And the outer peripheral part is sealed with sealing materials, such as glass frit. Then, for example, a mixed gas of neon (Ne) and xenon (Xe) is sealed in the discharge space inside as a discharge gas.

  The discharge space is partitioned into a plurality of sections by barrier ribs 24, and discharge cells constituting pixels are formed at portions where display electrode pairs 14 and data electrodes 22 intersect. A color image is displayed on the panel 10 by discharging and emitting (lighting) these discharge cells.

  As described above, the panel 10 faces the front substrate 11 on which the plurality of display electrode pairs 14 are formed and the rear substrate 21 on which the plurality of data electrodes 22 are formed so that the display electrode pairs 14 and the data electrodes 22 cross each other. It is arranged and formed.

  In panel 10, three consecutive discharge cells arranged in the direction in which display electrode pairs 14 extend, that is, discharge cells that emit red (R), and discharge cells that emit green (G), One pixel is composed of three discharge cells, ie, discharge cells emitting blue (B).

  Note that the structure of the panel 10 is not limited to the above-described structure, and for example, the panel 10 may include a stripe-shaped partition wall. The mixing ratio of the discharge gas may be, for example, a xenon partial pressure of 10%, but the xenon partial pressure may be further increased in order to improve the light emission efficiency in the discharge cell. Good.

  FIG. 2 is an electrode array diagram of panel 10 used in the plasma display device in accordance with the first exemplary embodiment of the present invention.

  The panel 10 includes n scan electrodes 12 and n sustain electrodes 13 extended in the horizontal direction (row direction, line direction), and m data electrodes extended in the vertical direction (column direction). 22 are arranged.

  One discharge cell is formed in a region where a pair of scan electrode 12 and sustain electrode 13 intersects with one data electrode 22. In other words, m discharge cells are formed on one pair of display electrodes 14 and m / 3 pixels are formed. Then, m × n discharge cells are formed in the discharge space, and an area where m × n discharge cells are formed in a matrix form becomes an image display area of the panel 10. For example, in a panel having 1920 × 1080 pixels, m = 1920 × 3 and n = 1080. In the present embodiment, n = 1080, but the present invention is not limited to this value.

  FIG. 3 is a diagram schematically showing an example of a drive voltage waveform applied to each electrode of panel 10 used in the plasma display device in accordance with the first exemplary embodiment of the present invention.

  FIG. 3 shows drive voltage waveforms applied to scan electrode 12, sustain electrode 13 and data electrode 22, respectively. The drive voltage waveform applied to the scan electrode 12 is applied to each of the scan electrode 12 that performs the address operation first in the address period, the scan electrode 12 that performs the address operation second, and the scan electrode 12 that performs the address operation last. An example of the driving voltage waveform is shown.

  One field is composed of a plurality of subfields having different emission luminances (luminance weights) (for example, eight subfields from subfield SF1 to subfield SF8). Each subfield has an initialization period Ti, an address period Tw, and a sustain period Ts. In each discharge cell, light emission / non-light emission is controlled for each subfield based on an image signal. Thereby, each discharge cell emits light with brightness according to the image signal. FIG. 3 shows an example of drive voltage waveforms in three subfields of subfield SF1, subfield SF2, and subfield SF3.

  In the initialization period Ti of the subfield SF1, the voltage 0 (V) is applied to the data electrode 22 and the sustain electrode 13. A voltage Vi1 is applied to the scan electrode 12 after a voltage 0 (V) is applied, and an upward ramp waveform voltage (upramp voltage) that gradually increases from the voltage Vi1 toward the voltage Vi2 is applied. Voltage Vi1 is set to a voltage lower than the discharge start voltage with respect to sustain electrode 13, and voltage Vi2 is set to a voltage exceeding the discharge start voltage.

  While this up-ramp voltage rises, a weak initializing discharge is continuously generated in each discharge cell.

  Subsequently, a positive voltage Ve is applied to the sustain electrode 13 and a voltage 0 (V) is applied to the data electrode 22. A downward ramp waveform voltage (down-ramp voltage) that gently falls from the voltage Vi3 toward the negative voltage Vi4 is applied to the scan electrode 12. Voltage Vi3 is set to a voltage that is less than the discharge start voltage with respect to sustain electrode 13, and voltage Vi4 is set to a voltage that exceeds the discharge start voltage.

  While this down-ramp voltage falls, a weak initializing discharge is continuously generated in each discharge cell.

  Thus, the initialization operation in the initialization period of the subfield SF1 is completed, and wall charges necessary for the address operation in the subsequent address period Tw are formed on each electrode.

  As shown in the initialization period Ti of the subfield SF2 and the subfield SF3, as the operation in the initialization period Ti, it is only necessary to apply the down-ramp voltage to the scan electrode 12.

  In the address period Tw, the voltage Ve is applied to the sustain electrode 13, the voltage 0 (V) is applied to the data electrode 22, and the voltage Vc is applied to the scan electrode 12.

  Next, a negative scan pulse with a negative voltage Va is applied to the scan electrode 12 in the first row where the address operation is performed first. At the same time, a positive address pulse having a positive voltage Vd is applied to the data electrode 22 corresponding to the discharge cell to emit light in the first row.

  In the discharge cell (discharge cell to emit light) to which the scan pulse and the address pulse are applied simultaneously, an address discharge occurs, and wall charges necessary for the sustain operation in the subsequent sustain period Ts are formed on each electrode. In the discharge cells to which no address pulse is applied, no address discharge occurs.

  In this way, the address operation in the discharge cells in the first row is completed.

  A similar address operation is sequentially performed until the discharge cell in the last row, and the address period of the subfield SF1 ends.

  In sustain period Ts, voltage 0 (V) is applied to sustain electrode 13, and a sustain pulse of positive voltage Vs is applied to scan electrode 12.

  As a result, a sustain discharge occurs in the discharge cell that has generated the address discharge. And the fluorescent substance layer 25 light-emits with the ultraviolet-ray which generate | occur | produced by this sustain discharge. Further, due to this sustain discharge, wall charges necessary for the immediately subsequent sustain operation are formed on each electrode. No sustain discharge occurs in the discharge cells in which no address discharge has occurred during the address period.

  Subsequently, the voltage 0 (V) is applied to the scan electrode 12, and the sustain pulse of the voltage Vs is applied to the sustain electrode 13. In the discharge cell that has generated the sustain discharge immediately before, the sustain discharge occurs again, and the phosphor layer 25 emits light. Further, due to this sustain discharge, wall charges necessary for the immediately subsequent sustain operation are formed on each electrode.

  Thereafter, similarly, the number of sustain pulses corresponding to the luminance weight is alternately applied to scan electrode 12 and sustain electrode 13. Thus, the discharge cells that have generated the address discharge in the address period emit light with a luminance corresponding to the luminance weight.

  After the sustain pulse is generated in the sustain period, the ramp waveform gradually rises from the voltage 0 (V) to the voltage Vr to the scan electrode 12 while the voltage 0 (V) is applied to the sustain electrode 13 and the data electrode 22. Apply voltage (erase lamp voltage).

  As a result, a weak erasure discharge is generated in the discharge cell that has generated the sustain discharge, and unnecessary wall charges in the discharge cell are erased.

  Thus, the subfield SF1 is completed. The drive voltage waveform in the other subfields is substantially the same as the drive voltage waveform in subfield SF1 except that no upramp voltage is generated in initialization period Ti and the number of sustain pulses generated in the sustain period is different. Description is omitted.

  The values of the voltages in the present embodiment are, for example, voltage Vi2 = 440 (V), voltage Vi4 = −80 (V), voltage Va = −85 (V), voltage Vs = voltage Vr = 200 (V ) And voltage Ve = 150 (V).

  However, the voltage values described above are merely examples, and each voltage value is desirably set optimally based on the discharge characteristics of the panel, the specifications of the plasma display device, and the like.

  In the sustain period, a very large current exceeding several tens of amperes instantaneously flows through the sustain electrode 13 as the sustain discharge occurs. In such an electronic component that controls a large current, a large amount of heat is generated.

  FIG. 4 is a diagram schematically showing an example of a circuit block constituting the plasma display device 30 according to the first embodiment of the present invention.

  The plasma display device 30 includes a panel 10 and a drive circuit that drives the panel 10.

  The drive circuit includes an image signal processing circuit 31, a data electrode drive circuit 32, a scan electrode drive circuit 33, a sustain electrode drive circuit 34, a timing generation circuit 35, and a power supply circuit (not shown) that supplies necessary power to each circuit block. It has.

  The image signal processing circuit 31 assigns a gradation value to each discharge cell based on the inputted image signal, and the gradation value is assigned to the image data indicating light emission / non-light emission for each subfield (light emission / non-light emission digitally). Data corresponding to “1” and “0” of the signal).

  The timing generation circuit 35 generates various timing signals for controlling the operation of each circuit block based on the horizontal synchronization signal and the vertical synchronization signal. Then, the generated timing signal is supplied to each circuit block.

  The data electrode driving circuit 32 generates an address pulse corresponding to each data electrode 22 based on the image data output from the image signal processing circuit 31 and the timing signal supplied from the timing generation circuit 35, and applies to each data electrode 22. Apply.

  Scan electrode drive circuit 33 includes a sustain pulse generation circuit, a ramp voltage generation circuit, and a scan pulse generation circuit (not shown in FIG. 4), and generates a drive voltage waveform based on a timing signal supplied from timing generation circuit 35. Created and applied to each scan electrode 12. The sustain pulse generation circuit generates a sustain pulse during the sustain period based on the timing signal and applies it to scan electrode 12.

  Sustain electrode drive circuit 34 includes a sustain pulse generation circuit and a circuit (not shown in FIG. 4) for generating voltage Ve, creates a drive voltage waveform based on the timing signal supplied from timing generation circuit 35, The voltage is applied to each sustain electrode 13. The sustain pulse generation circuit generates a sustain pulse during the sustain period based on the timing signal and applies the sustain pulse to sustain electrode 13.

  FIG. 5 is a circuit diagram schematically showing a configuration example of sustain pulse generating circuit 40 used in plasma display device 30 in the first exemplary embodiment of the present invention. Sustain pulse generation circuit 40 is provided on each of scan electrode 12 side and sustain electrode 13 side. The output terminal of sustain pulse generating circuit 40 on the scan electrode 12 side is connected to scan electrode 12, and the output terminal of sustain pulse generating circuit 40 on the sustain electrode 13 side is connected to sustain electrode 13. Each switching element of sustain pulse generating circuit 40 is controlled by a timing signal supplied from timing generating circuit 35, but details of the signal path of the timing signal are omitted in FIG.

  In the following, the sustain pulse generation circuit 40 on the scan electrode 12 side will be described as an example, but the sustain pulse generation circuit 40 on the sustain electrode 13 side has the same configuration as the sustain pulse generation circuit 40 on the scan electrode 12 side. Since the same operation is performed, the description is omitted. Regarding the sustain pulse generating circuit 40 on the sustain electrode 13 side, the following scan electrode 12 may be replaced with the sustain electrode 13.

  The sustain pulse generation circuit 40 includes a power recovery unit 41 and a clamp unit 45, and generates a sustain pulse to be applied to the scan electrode 12 in the sustain period Ts.

  The power recovery unit 41 includes a power recovery capacitor C41, switching elements Q42 and Q43, diodes D42 and D43, and a resonance inductor L41. Then, the power recovery unit 41 uses the LC resonance to recover the power stored in the interelectrode capacitance Cp of the panel 10 in the power recovery capacitor C41, and the power stored in the power recovery capacitor C41 is the scan electrode. Reused for 12 driving.

  The clamp part 45 has switching elements Q46 and Q47. Scan electrode 12 is clamped to voltage Vs via switching element Q46 and clamped to voltage 0 (V) via switching element Q47.

  Sustain pulse generation circuit 40 switches each switching element based on the timing signal output from timing generation circuit 35 to generate a sustain pulse.

  When the sustain pulse is raised, only the switching element Q42 is turned on to cause the equivalent capacitance Cp of the scan electrode 12, which is a capacitive load, and the inductor L41 to LC resonate to switch the charge stored in the power recovery capacitor C41. It moves to the equivalent capacitance Cp via the element Q42, the diode D42 and the inductor L41. When the voltage of the scan electrode 12 approaches the voltage Vs, the switching element Q46 is turned on to clamp the scan electrode 12 at the voltage Vs.

  When the sustain pulse is lowered, only the switching element Q43 is turned on to cause LC resonance between the equivalent capacitance Cp and the inductor L41, and the charge stored in the scan electrode 12 is converted into power via the inductor L41, the diode D43 and the switching element Q43. It collects in the collection capacitor C41. When the voltage of the scan electrode 12 approaches the voltage 0 (V), the switching element Q47 is turned on to clamp the scan electrode 12 at the voltage 0 (V).

  Sustain pulse generation circuit 40 generates a sustain pulse in this way and applies it to scan electrode 12.

  As described above, the power recovery unit 41 performs charging / discharging of the equivalent capacity Cp having a large capacity via the switching elements Q42 and Q43, the diodes D42 and D43, and the inductor L41. In addition, the clamp unit 45 causes a large discharge current due to the sustain discharge to flow through the switching elements Q46 and Q47. Therefore, a very large current flows instantaneously through these electronic components, and a large amount of heat is generated accordingly.

  Therefore, in general, these electronic components are mounted on a circuit board with a cooling heat sink attached. In order to reduce the current flowing through each electronic component and suppress heat generation, the electronic components such as switching elements Q42 and Q43 and diodes D42 and D43 are configured by connecting a plurality of electronic components in parallel. do it. However, the number of electronic components that can be installed on the circuit board is limited depending on the size of the circuit board, the cost for manufacturing, and the like. Therefore, the number of electronic components that can be connected in parallel is limited.

  FIG. 6 schematically shows a part of circuit board 60 used in plasma display device 30 in the first exemplary embodiment of the present invention. FIG. 6 shows a state in which the electronic component 62 having a relatively large amount of heat generation and the heat sink 64 corresponding to the electronic component 62 are mounted on the circuit board 60.

  The electronic component 62 is, for example, the switching elements Q42, Q43, Q46, and Q47 shown in FIG. These are, for example, power transistors such as MOSFETs for high withstand voltage and large current and IGBTs (Insulated Gate Bipolar Transistors). Alternatively, the electronic component 62 is the diodes D42 and D43 shown in FIG.

  In the present embodiment, these electronic components 62 are enclosed in a surface mount type package. An electrode terminal portion also serving as a heat sink is provided on the back side of the package, and this electrode terminal portion is directly soldered to a copper foil provided on the surface of the circuit board 60. Therefore, the heat generated in the electronic component 62 is transmitted to the copper foil on the circuit board 60 through the electrode terminal portion on the back side of the package.

  In this embodiment, the heat radiating plate 64 is not directly attached to the heat generating electronic component 62 but mounted on the copper foil provided on the surface of the circuit board 60.

  In other words, the heat sink 64 is mounted on a copper foil provided by extending a copper foil to which the electrode terminal portion on the back side of the package of the electronic component 62 is soldered.

  The heat radiating plate 64 has an opening, and when the heat radiating plate 64 is mounted on the circuit board 60, a ventilation tunnel is formed between the opening and the circuit board 60.

  The heat radiating plate 64 radiates heat generated through the copper foil on the circuit board 60 from the electrode terminal portion that also serves as the heat radiating plate provided on the back side of the package of the electronic component 62. .

  At this time, the heat sink is arranged on the circuit board 60 so that the electronic component 62 to be radiated by the heat radiating board 64 is not located in the extending direction of the ventilation tunnel formed by the heat radiating board 64 and the circuit board 60. 64 and the electronic component 62 are arranged. That is, in the heat sink 64 and the electronic component 62, the line drawn in the extending direction of the ventilation tunnel formed by the heat sink 64 and the electronic component 62 intersects the line connecting the heat sink 64 and the electronic component 62. Is disposed on the circuit board 60.

  The heat sink 64 and the electronic component 62 are placed on the circuit board 60 so that the distance between the electronic component 62 and the heat sink 64 (the distance between the electronic component 62 and the heat sink 64) is within 10 mm, preferably within 5 mm. Deploy.

  FIG. 7 is a diagram illustrating an example of an actual measurement value of the temperature of the circuit board 60 on which the electronic component 62 that generates heat is mounted in the plasma display device 30 according to the first exemplary embodiment of the present invention.

  In FIG. 7, the horizontal axis indicates the distance from the electronic component 62 to the temperature measurement point, and the vertical axis indicates the temperature of the copper foil surface at the temperature measurement point of the circuit board 60. FIG. 7 shows the measurement results of four samples from Sample 1 to Sample 4.

  As shown in FIG. 7, the temperature of the copper foil surface decreases as the distance from the electronic component 62 increases. Therefore, the heat dissipating effect of the heat dissipating plate 64 decreases as the disposition position of the heat dissipating plate 64 is further away from the electronic component 62.

  Based on the experimental results shown in FIG. 7, it is desirable to dispose the heat sink 64 at a position where the distance between the heat sink 64 and the electronic component 62 is within 10 mm. It is desirable to dispose the heat sink 64 at a position where the distance between the heat sink 64 and the electronic component 62 is within 5 mm.

  In the present embodiment, as shown in FIG. 10 to be described later, one side closest to the heat sink 64 in the package enclosing the electronic component 62 and the position closest to the electronic component 62 in the heat sink 64 are present. The distance from one side is the distance between the electronic component 62 and the heat sink 64.

  FIG. 8 is a diagram showing an example of the shape of the heat sink 64 used in the plasma display device 30 according to the first embodiment of the present invention. FIG. 8 shows a view of the heat radiating plate 64 from three directions (a plan view, a front view below the plan view, and a side view next to the plan view). FIG. 8 shows the height of the heat sink 64 as h1, the width including the solder bonding area 65 as w1, the width excluding the solder bonding area 65 as w2, the length as d1, and the thickness as t1.

  The heat sink 64 shown in the present embodiment has the following shape.

  The heat radiating plate 64 has an opening 67 and solder bonding regions 65 provided on both sides of the opening 67. The opening 67 is formed by being surrounded by two side plate portions 166 and a top plate portion 167. The solder bonding region 65 is provided so as to be connected to the side plate portion 166.

  The solder bonding area 65 is an area for bonding the heat sink 64 to the circuit board 60 by soldering. The opening 67 is covered with the circuit board 60 by bonding the solder bonding region 65 to the circuit board 60. As a result, the circuit board 60 is provided with the ventilation tunnel 66 surrounded by the circuit board 60 and the heat radiating plate 64 (two side plate portions 166 and the top plate portion 167) and opened at two locations of one end and the other end. Can be formed on top.

  The shape of the heat radiating plate 64 when viewed from the direction in which the heat radiating plate 64 extends, that is, the direction in which the ventilation tunnel extends, is “U” -shaped (“U” -shaped in the opposite direction in the front view shown in FIG. 8). The shape is as follows. That is, the shape of the opening 67 is “U” -shaped (“U” -shaped in the opposite direction in the front view shown in FIG. 8). Therefore, in the heat radiating plate 64, solder bonding regions 65 are formed on both sides of the “U” -shaped opening 67. The heat sink 64 has such a shape.

  The solder bonding region 65 is not limited to the shape shown in FIG. The solder bonding area 65 of the heat sink 64 may have any shape as long as the heat sink 64 can be fixed to the circuit board 60. For example, a through hole is provided in the circuit board 60 and the solder bonding area 65 is formed to penetrate the through hole. After the solder bonding area 65 is passed through the through hole, the heat sink 64 is attached to the circuit board 60 by soldering. It may be fixed.

  FIG. 9 is a perspective view showing an example of a heat radiating plate bonding region 69 to which the heat radiating plate 64 provided on the circuit board 60 in Embodiment 1 of the present invention is bonded.

  The heat radiating plate 64 is mounted on the circuit board 60 by bonding the copper foil 70 provided on the surface of the circuit board 60 and the solder bonding region 65 by soldering. Therefore, the copper foil 70 is provided with a heat radiating plate bonding area 69 for bonding the solder bonding area 65.

  In the present embodiment, as shown in FIG. 9, the heat sink adhesion area 69 provided on the copper foil 70 of the circuit board 60 has a plurality of rectangular shapes extending in one direction (for example, one heat sink 64. 2 regions) are arranged in parallel.

  FIG. 10 is a perspective view showing an example of an arrangement position of the heat sink 64 and the electronic component 62 mounted on the circuit board 60 in the first embodiment of the present invention.

  In FIG. 10, the distance between the heat radiating plate 64 and the electronic component 62 is indicated as “L”.

  The heat sink 64 having the shape shown in FIG. 8 is installed on the circuit board 60 so that the “U” -shaped opening 67 is closed by the circuit board 60, and the solder bonding region 65 of the heat sink 64 is disposed on the circuit board 60. It solders to the heat sink adhesion area 69 provided on the copper foil 70. Thereby, a ventilation tunnel 66 surrounded by the heat radiating plate 64 (two side plate portions 166 and the top plate portion 167) and the circuit board 60 is formed on the circuit board 60.

  As shown in FIG. 10, the heat radiating plate 64 is a line drawn in the direction in which the ventilation tunnel 66 extends on a copper foil 70 provided by extending the copper foil to which the electronic component 62 is soldered (for example, ventilation ventilation). A line passing through the center of the tunnel 66. This is indicated by a broken line in Fig. 10. Note that this line is not actually provided on the heat sink 64, and a line connecting the heat sink 64 and the electronic component 62 (for example, the heat sink 64). And a line passing through the center of the electronic component 62. This is indicated by a one-dot chain line in Fig. 10. Note that this line is not actually provided on the heat radiating plate 64). And in this Embodiment, the distance L of the heat sink 64 and the electronic component 62 is less than 10 mm, Preferably it is less than 5 mm.

  By mounting the heat sink 64 on the circuit board 60 in this way, the ventilation tunnel 66 is formed on the circuit board 60. The heat dissipation effect in the heat radiating plate 64 is enhanced by the air flowing through the ventilation tunnel 66. That is, the heat generated in the electronic component 62 is transferred to the heat radiating plate 64 having a high heat radiating effect through the copper foil 70 on the circuit board 60 and is radiated.

  In the present embodiment, the heat radiation effect of the heat radiating plate 64 is enhanced by flowing air through the ventilation tunnel 66. Therefore, it is important that the air flowing through the ventilation tunnel 66 is not blocked by an obstacle. Therefore, in the present embodiment, the electronic component 62 is not arranged in the direction in which the ventilation tunnel 66 extends so that the electronic component 62 does not block the air flowing through the ventilation tunnel 66. That is, the electronic component 62 is arranged so that a line drawn in the direction in which the ventilation tunnel 66 extends and a line connecting the heat sink 64 and the electronic component 62 intersect.

  Further, it is desirable that the heat radiating plate 64 be disposed on the circuit board 60 so that the direction in which the ventilation tunnel 66 extends is vertical within the housing of the image display device. As a result, a laminar flow (upward airflow) directed from the lower side to the upper side flows through the ventilation tunnel 66, so that the air flow in the ventilation tunnel 66 can be made smooth and the heat dissipation effect in the heat radiating plate 64 can be further enhanced.

  Further, when mounting a plurality of heat sinks 64 on the circuit board 60, it is desirable to dispose the heat sinks 64 so that the ventilation tunnels 66 extend in the same direction. Thereby, the air passing through the plurality of ventilation tunnels 66 flows more smoothly. The direction is more preferably a vertical direction.

In the present embodiment, the heat radiation plate 64 has a height h1 of 10 mm, a width w1 including the solder bonding region 65 of 10 mm, a width w2 excluding the solder bonding region 65 of 8 mm, and a length d1 of 15 mm. . At this time, the volume enveloped by the heat sink 64 is 1200 mm ³ , and the surface area of the heat sink 64 is 840 mm ² .

  Further, in order to enhance the heat dissipation effect of the heat radiating plate 64, it is desirable to increase the thickness of the heat radiating plate 64. However, if the thickness of the heat radiating plate 64 is too thick, when the heat radiating plate 64 is soldered to the circuit board 60 by the reflow method, the temperature of the solder paste does not rise sufficiently, and a defect may occur in the soldering process. There is. Therefore, it is desirable to set the thickness of the heat radiating plate 64 in consideration of the heat radiating effect and the soldering method. In the present embodiment, the thickness t1 of the heat sink 64 is set to 0.3 mm on the premise that the soldering when attaching the heat sink 64 to the circuit board 60 is performed by the reflow method.

  However, in the present invention, each dimension of the heat sink 64 is not limited to these numerical values. Each dimension of the heat sink 64 is preferably set optimally based on the manufacturing process, the dimension of the circuit board 60, the amount of heat generated by the electronic component, and the like.

  In addition, the material forming the heat sink 64 is preferably a material having high thermal conductivity, low cost, and easy processing. In the present embodiment, an aluminum plate that is high in thermal conductivity, inexpensive, and easy to process is used as the material of the heat radiating plate 64. In consideration of adhesiveness when soldering, the surface of the aluminum plate is plated with nickel and tin. However, in this invention, the material of the heat sink 64 is not limited to the above-mentioned material, For example, an iron plate and a copper plate may be sufficient. Moreover, you may paint the surface of the heat sink 64 black as needed.

  The heat radiating plate 64 is provided on such a metal plate four times in order to provide a boundary (two places) between the solder bonding region 65 and the side plate portion 166 and a boundary (two places) between the top plate portion 167 and the side plate portion 166. It is formed by performing the bending process.

  Next, a method for mounting the heat sink 64 on the circuit board 60 will be described.

  First, a solder paste is applied to a region on the circuit board 60 where the electronic component 62 and the heat sink 64 are mounted by a screen printing method or the like. As for the region where the heat sink 64 is mounted, a solder paste may be applied to the portion where the solder bonding region 65 contacts the circuit board 60.

  Next, the electronic component 62 and the heat radiating plate 64 are installed on the circuit board 60 to which the solder paste has been applied, using, for example, a NC control (Numerical Control) mounter device or the like. As for the heat sink 64, the heat sink 64 is sucked by using, for example, a vacuum suction head and installed at a predetermined position.

  Next, the circuit board 60 on which the electronic component 62 and the heat sink 64 are mounted is placed in a reflow furnace and preheated to 180 ° C. Next, the circuit board 60 is rapidly heated to 260 ° C. to melt the solder paste. Next, the circuit board 60 is quickly cooled, and the electronic component 62 and the heat sink 64 are bonded to the circuit board 60. In this way, the electronic component 62 and the heat sink 64 are soldered to the circuit board 60.

  In addition, the heat sink adhesion area | region 69 on the copper foil 70 which adhere | attaches the solder adhesion area | region 65 of the heat sink 64 is two rectangular areas which are not mutually connected. Therefore, the contact area between the heat sink 64 and the circuit board 60 is narrow, and the heat sink 64 can be soldered to the circuit board 60 by the reflow method simultaneously with other electronic components. Thus, the heat sink 64 in the present embodiment can be mounted on the circuit board 60 reliably and inexpensively without increasing the number of steps in the manufacturing process.

(Embodiment 2)
In the first embodiment, an example in which the shape of the opening 67 of the heat radiating plate 64 is a “U” shape has been described, but the present invention limits the shape of the opening of the heat radiating plate to a “U” shape. is not.

  FIG. 11 is a diagram illustrating an example of the shape of the heat sink 74 used in the plasma display device 30 according to the second embodiment of the present invention. FIG. 11 shows a view of the heat radiating plate 74 from three directions (a plan view, a front view below the plan view, and a side view next to the plan view). In FIG. 11, the height of the heat sink 74 is h1, the width including the solder bonding region 75 is w1, the width excluding the solder bonding region 75 is w2, and the width of the region forming one opening is w3. The thickness is shown as d1, and the thickness is shown as t1.

  The heat sink 74 shown in the present embodiment has the following shape.

  The heat sink 74 has a shape in which the shape of the opening when viewed from the direction in which the heat sink 74 extends is an “M” shape (shown in the front view of FIG. 11). That is, the heat radiating plate 74 includes two openings 78, two solder bonding regions 75 provided on both sides of the two openings 78, and one solder bonding region 77 sandwiched between the two openings 78. Three solder bonding regions 75 and 77 are provided.

  The two openings 78 are formed by being surrounded by the inner plate portion 176, the outer plate portion 178, and the top plate portion 177, respectively. Therefore, the heat sink 74 has two inner plate portions 176, two outer plate portions 178 and two top plate portions 177. The solder bonding area 75 is provided in connection with the outer plate portion 178, and the solder bonding area 77 is provided in connection with the inner plate portion 176.

  By bonding these three solder bonding regions 75 and 77 to the copper foil 70 of the circuit board 60 by soldering, the two openings 78 are each covered with the circuit board 60. As a result, the tunnel substrate is surrounded by the circuit board 60 and the heat radiating plate 74 (the inner plate portion 176, the outer plate portion 178, and the top plate portion 177) and has two openings, one end and the other end. The two ventilation tunnels 76 are formed on the circuit board 60.

  Note that the solder bonding region 75 is not limited to the shape shown in FIG. The solder bonding region 75 of the heat sink 74 may have any shape as long as the heat sink 74 can be fixed to the circuit board 60. For example, a through hole is provided in the circuit board 60 and the solder bonding area 75 is formed to penetrate the through hole. After the solder bonding area 75 is passed through the through hole, the heat sink 74 is attached to the circuit board 60 by soldering. It may be fixed.

In the present embodiment, the heat sink 74 has a height h1 of 10 mm, a width w1 including the solder bonding region 75 of 10 mm, a width w2 excluding the solder bonding region 75 of 8 mm, and a width of a region where one opening is formed. w3 is set to 2.5 mm, the length d1 is set to 15 mm, and the thickness t1 is set to 0.3 mm. At this time, the volume enveloped by the heat sink 74 is 1200 mm ³ , and the surface area of the heat sink 74 is 1410 mm ² .

  Further, as the material of the heat radiating plate 74, as with the heat radiating plate 64, an aluminum plate plated with nickel and tin is used.

  The heat radiating plate 74 is formed of such a metal plate on the boundary (two places) between the solder bonding region 75 and the outer plate portion 178, on the boundary between the solder bonding region 77 and the inner plate portion 176 (two places), In order to provide the boundary between the portion 177 and the inner plate portion 176 and the boundary between the outer plate portions 178 (2 locations × 2), the plate is formed by performing bending eight times.

  However, in the present invention, each dimension of the heat sink 74 is not limited to these numerical values. Each dimension of the heat sink 74 is preferably set optimally based on the manufacturing process, the dimension of the circuit board 60, the amount of heat generated by the electronic component, and the like. Moreover, the material of the heat sink 74 is not limited to the above-described material, and may be, for example, an iron plate or a copper plate. Moreover, you may coat the surface of the heat sink 74 black as needed.

  Note that the method of mounting the heat sink 74 on the circuit board 60 is the same as the method of mounting the heat sink 64 shown in the first embodiment on the circuit board 60, and thus the description thereof is omitted.

  Since the heat sink 74 in the present embodiment has more bent portions than the heat sink 64 shown in the first embodiment, the surface area is large and the heat dissipation effect is high. Further, since the heat sink 74 is bonded to the circuit board 60 by the three solder bonding regions 75 and 77, the mechanical strength related to bonding is stronger than when the heat sink 64 is bonded to the circuit board 60. Have.

(Embodiment 3)
FIG. 12 is a front view showing an example of the shape of the heat sink 84 in the third embodiment of the present invention. In FIG. 12, the front view when the heat sink 84 is seen from the direction where the heat sink 84 is extended is shown. In FIG. 12, the height of the heat sink 84 is h1, the width including the solder bonding region 85 is w1, the width excluding the solder bonding region 85 is w2, the width of the region forming one small opening is w3, The length is indicated by d1, the height to the small opening 81 is indicated by h2, and the thickness is indicated by t1.

  The heat sink 84 shown in the present embodiment has the following shape.

  As shown in FIG. 12, the heat sink 84 has a shape in which the shape of the opening when viewed from the direction in which the heat sink 84 extends is an “M” shape.

  However, unlike the heat radiating plate 74 shown in the second embodiment, the heat radiating plate 84 is formed so that the tip of the region sandwiched between the two openings is higher than the bonding surface with the circuit board 60. Is not the solder bonding area, but is used as the inner top plate portion 87. Therefore, in the present embodiment, these two openings are called “small openings”. That is, the heat radiating plate 84 has a shape having two small openings 81 above one opening 83.

  The two small openings 81 are surrounded by the inner plate 186, the outer plate 188, and the outer top plate 187, respectively. Accordingly, the opening 83 having the two small openings 81 is surrounded by the two inner plate portions 186, the two outer plate portions 188, the two outer top plate portions 187, and the one inner top plate portion 87. Is done. Therefore, the heat radiating plate 84 has two inner plate portions 186, two outer plate portions 188, two outer top plate portions 187, and one inner top plate portion 87. The solder bonding area 85 is provided so as to be connected to the outer side plate portion 188.

  Therefore, the solder bonding regions 85 of the heat sink 84 are two places on both sides of the “M” -shaped opening 83.

  The opening 83 is covered with the circuit board 60 by bonding these two solder bonding regions 85 to the copper foil 70 of the circuit board 60 by soldering. Thus, the circuit board 60 and the heat radiating plate 84 (the two inner plate portions 186, the two outer plate portions 188, the two outer top plate portions 187, and the one inner top plate portion 87 are surrounded by one end portion). Two ventilation tunnels 86 are formed on the circuit board 60. The ventilation tunnel 86 is formed in a “C” -shaped tunnel shape as shown in FIG. Become.

  The solder bonding region 85 is not limited to the shape shown in FIG. The solder bonding area 85 of the heat sink 84 may have any shape as long as the heat sink 84 can be fixed to the circuit board 60. For example, a through hole is provided in the circuit board 60, and the solder bonding area 85 is formed to penetrate the through hole. After the solder bonding area 85 is passed through the through hole, the heat sink 84 is attached to the circuit board 60 by soldering. It may be fixed.

The heat sink 84 in the present embodiment forms, for example, a small opening by 10 mm in height h 1, 10 mm in width w 1 including the solder bonding region 85, 8 mm in width w 2 excluding the solder bonding region 85. The width w3 of the region is set to 2.5 mm, the height h2 to the small opening 81 is set to 5 mm, the length d1 is set to 15 mm, and the thickness t1 is set to 0.3 mm. At this time, the volume enveloped by the heat sink 84 is 1200 mm ³ , and the surface area of the heat sink 84 is 1140 mm ² .

  Further, as the material of the heat radiating plate 84, similarly to the heat radiating plate 64, an aluminum plate plated with nickel and tin is used.

  The heat radiating plate 84 is attached to such a metal plate at the boundary between the solder bonding area 85 and the outer plate portion 188 (two locations), the boundary between the inner top plate portion 87 and the inner plate portion 186 (two locations), In order to provide the boundary between the top plate portion 187 and the inner plate portion 186 and the boundary (two locations × 2) between the outer plate portions 188, the bending is performed eight times.

  However, in the present invention, each dimension of the heat sink 84 is not limited to these numerical values. Each dimension of the heat sink 84 is desirably set optimally based on the manufacturing process, the dimension of the circuit board 60, the amount of heat generated by the electronic component, and the like. Moreover, the material of the heat sink 84 is not limited to the above-described material, and may be, for example, an iron plate or a copper plate. Moreover, you may paint the surface of the heat sink 84 black as needed.

  The method for mounting the heat radiating plate 84 on the circuit board 60 is the same as the method for mounting the heat radiating plate 64 shown in the first embodiment on the circuit board 60, and thus the description thereof is omitted.

  Since the heat sink 84 in the present embodiment has more bent portions than the heat sink 64 shown in the first embodiment, the surface area is large and the heat dissipation effect is high.

  Further, since the heat radiating plate 84 is bonded to the circuit board 60 at the two solder bonding regions 85, the surfaces of the two solder bonding regions 85 may be aligned on one plane. Therefore, the heat sink 84 can easily form the solder bonding region 85 as compared with the heat sink 74.

  In addition, the shape of the heat sink in this Embodiment is not limited to the shape shown in FIG. The heat sink in the present embodiment only needs to be formed such that the tip of the region sandwiched between the two small openings is higher than the bonding surface between the circuit board 60 and the heat sink.

  FIG. 13: is a front view which shows another example of the shape of the heat sink in Embodiment 3 of this invention.

  For example, in the present embodiment, as shown as a heat sink 94 in FIG. 13, the heat sink 94 is not provided with the inner top plate 87, and the region sandwiched between the two small openings 82 is “V” -shaped. You may have the shape used as a type | mold (namely, the shape formed by the two inner side board parts 182 is a "V" shape). Even with the heat sink 94 having such a shape, substantially the same effect as that of the heat sink 84 shown in FIG. 12 can be obtained.

(Embodiment 4)
FIG. 14 is a front view showing an example of the shape of the heat sink in the fourth embodiment of the present invention. FIG. 14 shows a partially enlarged view of the solder bonding region 105 when the heat radiating plate 104 is soldered to the circuit board 60 together with a front view of the heat radiating plate 104.

  The heat sink 104 shown in FIG. 14 has substantially the same shape as the heat sink 64 shown in FIG. 8 in the first embodiment. However, it differs from the heat sink 64 in that the folded portion 106 is provided at the end of the solder bonding region 105.

  As shown in FIG. 14, in heat radiating plate 104 in the present embodiment, a folded portion 106 is provided at the end of solder bonding region 105. As a result, the fracture surface 107 at the tip of the folded-back portion 106 is kept away from the solder bonding portion between the circuit board 60 and the solder bonding region 105.

  There is no plating on the fracture surface of the metal plate, and solder may be relatively difficult to weld. Therefore, in this embodiment, the folded portion 106 is provided in the solder bonding region 105 of the heat radiating plate 104. By moving the metal plate fracture surface 107 away from the solder bonding portion in this way, when the heat radiating plate 104 is soldered to the circuit board 60, the solder can easily flow between the heat radiating plate 104 and the copper foil 70 on the circuit board 60. can do. As a result, as shown in the partially enlarged view of FIG. 14, a smooth solder fillet 108 can be formed between the solder bonding region 105 and the circuit board 60, and high-quality soldering can be performed. .

  FIG. 15A is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention.

  The heat sink 114 shown in FIG. 15A has substantially the same shape as the heat sink 74 shown in FIG. 11 in the second embodiment. Then, similarly to the heat radiating plate 104, a folded portion 116 is provided at the end of the solder bonding region 115.

  FIG. 15B is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention.

  The heat sink 124 shown in FIG. 15B has substantially the same shape as the heat sink 84 shown in FIG. 12 in the third embodiment. Then, similarly to the heat sink 104, a folded portion 126 is provided at the end of the solder bonding region 125.

  FIG. 15C is a front view showing another example of the shape of the heat sink in the fourth exemplary embodiment of the present invention.

  The heat sink 134 shown in FIG. 15C has substantially the same shape as the heat sink 94 shown in FIG. 13 in the third embodiment. Then, similarly to the heat radiating plate 104, a folded portion 136 is provided at the end of the solder bonding region 135.

  In these heat radiating plates as well, similar to the heat radiating plate 104, a smooth solder fillet 108 can be formed between the solder bonding region and the circuit board 60, and high-quality soldering can be performed.

  In each of the heat sinks described above, the height h3 of each of the folded portions 106, 116, 126, and 136 is 1 mm.

  However, in the present invention, the dimension of the folded portion is not limited to this value. The dimensions of the folded portion are desirably set optimally based on the manufacturing process, the dimensions of the heat sink, the material of the heat sink, and the like.

  In addition, although each heat sink mentioned above is formed with the aluminum plate which plated nickel and tin similarly to the heat sink 64, you may form with other materials, such as an iron plate and a copper plate, for example.

  Note that the method of mounting the heat sink shown in the present embodiment on the circuit board 60 is the same as the method of mounting the heat sink 64 shown in the first embodiment on the circuit board 60, and thus the description thereof is omitted.

(Embodiment 5)
In each of the above-described embodiments, the example in which the solder bonding area is provided outside the ventilation tunnel has been described. However, the present invention does not limit the position where the solder bonding area is provided outside the ventilation tunnel. In this embodiment, an example in which a solder bonding region is provided inside a ventilation tunnel will be described.

  FIG. 16A is a front view showing an example of the shape of the heat sink in Embodiment 5 of the present invention.

  The heat sink 144 shown in FIG. 16A has substantially the same shape as the heat sink 64 shown in FIG. 8 in the first embodiment. However, it differs from the heat radiating plate 64 in that the end of the heat radiating plate 144 is bent inside the heat radiating plate 144 and the solder bonding region 145 is formed inside the ventilation tunnel 149.

  By making the heat sink 144 in such a shape, the ratio of the “volume encapsulated by the heat sink (or the surface area of the heat sink)” to the “area required for mounting the heat sink on the circuit board” 8 can be made larger than the heat radiating plate 64 (the heat radiating plate 64 provided outside the ventilation tunnel 66).

For example, the area required when mounting the heat sink 64 shown in FIG. 8 on the circuit board 60 is length d1 × width w1, that is, 15 mm × 10 mm. And as above-mentioned, the volume enveloped by the heat sink 64 whose height h1 is 10 mm is 1200 mm < ³ >, and the surface area of the heat sink 64 is 840 mm < ² >.

On the other hand, the heat dissipating plate 144 shown in FIG. 16A has a height h1 set to 10 mm which is the same as that of the heat dissipating plate 64, and a width w1 of 10 mm and a length d1 so that it can be mounted in a 15 mm × 10 mm region on the circuit board 60. Is set to 15 mm. At this time, the volume enveloped by the heat sink 144 is 1500 mm ³ , and the surface area of the heat sink 144 is 900 mm ² . These numerical values are larger than those of the heat sink 64 shown in FIG. Therefore, if the “area required for mounting the heat sink on the circuit board” is the same, the surface area is increased compared to the heat sink 64 shown in FIG. 8 by making the heat sink 144 in the shape shown in FIG. The heat dissipation effect can be enhanced.

  FIG. 16B is a front view showing another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention.

  The heat sink 154 shown in FIG. 16B has substantially the same shape as the heat sink 74 shown in FIG. 11 in the second embodiment. However, similarly to the heat sink 144 shown in FIG. 16A, the end of the heat sink 154 is bent inside the heat sink 154 to form the solder bonding region 155 inside the wind tunnel 159.

  Therefore, if the “area required when the heat sink is mounted on the circuit board” is the same, the heat sink 154 can have a larger surface area than the heat sink 74 shown in FIG.

  FIG. 16C is a front view showing another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention.

  The heat sink 164 shown in FIG. 16C has substantially the same shape as the heat sink 84 shown in FIG. 12 in the third embodiment. Then, similarly to the heat sink 144 shown in FIG. 16A, the end of the heat sink 164 is bent inside the heat sink 164, and the solder bonding region 165 is formed inside the wind tunnel 169.

  Therefore, if the “area required when the heat sink is mounted on the circuit board” is the same, the heat sink 164 can have a larger surface area than the heat sink 84 shown in FIG.

  FIG. 16D is a front view showing another example of the shape of the heat sink in the fifth exemplary embodiment of the present invention.

  16D has substantially the same shape as the heat sink 94 shown in FIG. 13 in the third embodiment. Then, similarly to the heat sink 144 shown in FIG. 16A, the end of the heat sink 174 is bent inside the heat sink 174, and the solder bonding region 175 is formed inside the wind tunnel 179.

  Therefore, if the “area required when the heat sink is mounted on the circuit board” is the same, the heat sink 174 can have a larger surface area than the heat sink 94 shown in FIG.

  In each heat sink described above, the width w4 of each of the solder bonding regions 145, 155, 165, and 175 is 2 mm.

  However, in the present invention, the size of the solder bonding region is not limited to this value. It is desirable that the size of the solder bonding region is optimally set based on the manufacturing process, the size of the heat sink, the material of the heat sink and solder, and the like.

  In addition, although each heat sink mentioned above is formed with the aluminum plate which plated nickel and tin similarly to the heat sink 64, you may form with other materials, such as an iron plate and a copper plate, for example.

  Note that the method of mounting the heat sink shown in the present embodiment on the circuit board 60 is the same as the method of mounting the heat sink 64 shown in the first embodiment on the circuit board 60, and thus the description thereof is omitted.

  In the first, second, third, fourth, and fifth embodiments of the present invention, the plasma display panel is described as an example of the image display device. However, the present invention is not limited to the plasma display panel. It is not something. Examples of the image display device include a liquid crystal display panel (Liquid Crystal Display Panel) and an EL display panel (Electro Luminescence Display Panel) in addition to the plasma display panel. The present invention can also be applied to an image display apparatus using such an image display device, and the same effects as described above can be obtained.

  In the embodiment of the present invention, the configuration in which the copper foil is provided on the surface of the circuit board and the heat sink is mounted has been described. However, the material for forming the foil is not limited to copper, and aluminum or gold Any material having a high thermal conductivity, such as, may be used.

  The specific numerical values shown in the embodiments of the present invention are merely examples of the embodiments, and the present invention is not limited to these numerical values. Each numerical value is desirably set optimally according to the manufacturing process, the characteristics of the electronic component, the specifications of the plasma display device, and the like. Each of these numerical values is allowed to vary within a range where the above-described effect can be obtained.

  The heat sink of the present invention is useful for a circuit board or an image display device because it suppresses an increase in costs and man-hours for manufacturing the image display device and can be more stably attached to the circuit board.

DESCRIPTION OF SYMBOLS 10 Panel 11 Front substrate 12 Scan electrode 13 Sustain electrode 14 Display electrode pair 15, 23 Dielectric layer 16 Protection layer 21 Back substrate 22 Data electrode 24 Partition 25 Phosphor layer 30 Plasma display device 31 Image signal processing circuit 32 Data electrode drive circuit 33 Scan electrode drive circuit 34 Sustain electrode drive circuit 35 Timing generation circuit 40 Sustain pulse generation circuit 41 Power recovery unit 45 Clamp unit 60 Circuit board 62 Electronic component 64, 74, 84, 94, 104, 114, 124, 134, 144 154,164,174 Heat sink 65,75,77,85,105,115,125,135,145,155,165,175 Solder bonding area 66,76,86,149,159,169,179 Ventilation tunnel 67, 78,83 Opening 69 Heatsink bonding area 0 Copper foil 81, 82 Small opening 87 Inner top plate portion 106, 116, 126, 136 Folded portion 107 Fracture surface 108 Solder fillet 166 Side plate portion 167, 177 Top plate portion 176, 182, 186 Inner plate portion 178, 188 Outside Plate part 187 Outer top plate part C41 Power recovery capacitor D42, D43 Diode L41 Inductor Q42, Q43, Q46, Q47 Switching element

The opening 83 is covered with the circuit board 60 by bonding these two solder bonding regions 85 to the copper foil 70 of the circuit board 60 by soldering. Thus, the circuit board 60 and the heat sink 84 (two inner plate portions 186, two outer plate portions 188, two outer top plate portions 187, and one inner top plate portion 87 ) are surrounded by one end. Two ventilation tunnels 86 are formed on the circuit board 60, which are opened at two locations, the first portion and the other end portion. And this ventilation tunnel 86 becomes a "C" -shaped tunnel shape as shown in FIG.

Claims (5)

A heat sink having an opening and a solder bonding region provided on both sides of the opening,
When the solder bonding region is bonded to a circuit board, the opening is surrounded by the circuit board and the heat sink and has a shape that forms a ventilation tunnel in which one end and the other end are open. A heat sink characterized by that. A circuit board for mounting a heat sink and electronic components,
An opening and a solder bonding area provided on both sides of the opening; when the solder bonding area is bonded to the circuit board, the circuit board is surrounded by the heat sink and one end and the other The heat sink that forms a ventilation tunnel having an open end on the circuit board is mounted on the circuit board at a predetermined distance from an electronic component that is radiated by the heat sink, and the heat sink and the A circuit board, comprising: a heat radiating plate bonding region for bonding the heat radiating plate so that a line connecting an electronic component is arranged at a position intersecting with a line drawn in the extending direction of the ventilation tunnel. The heat sink adhesion region is a rectangular shape extending in one direction,
The circuit board according to claim 2, wherein the plurality of heat radiation plate bonding regions are arranged in parallel. The circuit board according to claim 2, wherein the heat radiation plate bonding region is formed so that the plurality of ventilation tunnels are in the same direction. An image display device comprising: an image display device; a drive circuit that drives the image display device; and a circuit board on which a heat sink is mounted,
The heat sink is
An opening, and a solder bonding area provided on both sides of the opening, and the opening is surrounded by the circuit board and the heat sink when the solder bonding area is bonded to the circuit board. It has a shape that forms a ventilation tunnel in which one end and the other end are open,
The circuit board is
The position where the heat dissipation plate is mounted at a predetermined distance from the electronic component radiated by the heat dissipation plate, and the line connecting the heat dissipation plate and the electronic component intersects the line drawn in the extending direction of the ventilation tunnel The image display device is characterized in that the heat radiating plate is disposed on the image display device.

Images