JP2005259831A - Booster circuit unit and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a booster circuit unit and an electronic apparatus having the same which is exactly mounted in a frame and keeps external forces applied to the frame hardly influencing a booster circuit and a circuit board on which it is formed. <P>SOLUTION: The electronic apparatus comprises a booster circuit unit 1 composed of a circuit board 3 having a booster circuit formed thereon and a flexible resin-made insulation case 2 fixed to the circuit board 3 so as to cover the board 3, and a frame 14 in which the booster circuit unit 1 is mounted. The insulation case 2 has an engaging part 5 for positioning it in the frame 14 at an extension 9 extending from a part involving the circuit board 3 and the frame 14 has a mating part 12 for mating with the engaging part 5 at a part on which the booster circuit unit 1 is mounted. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a booster circuit unit that supplies a high voltage necessary for lighting a fluorescent tube, for example, and an electronic device including the booster circuit unit. Specifically, the present invention relates to a flexible resin provided so as to cover a circuit board. The present invention relates to a booster circuit unit and an electronic device in which an engaging case for positioning with respect to the electronic device housing is provided in the insulating case.

  At present, cold cathode fluorescent lamps are widely used as a light source for a backlight of a liquid crystal display device used in, for example, a notebook computer. In order to light the cold cathode tube, a voltage as high as about 1000 V is required, and a booster circuit unit that boosts the voltage from a battery or the like and supplies it to the cold cathode tube is used for the lighting.

For example, as shown in FIG. 22, a booster circuit unit disclosed in Patent Document 1 includes a rectangular tube case formed by assembling a case main body 114 and a case lid 111 made of a steel plate, and a circuit board accommodated in the case. 112 and an insulating sheet 113 made of synthetic resin or the like and disposed along the inside of the case main body 114 and the case lid 111 so as to enclose the circuit board 112. At both ends in the longitudinal direction of the case body 114, there are provided mounting holes 114a and mounting notches 114b for mounting the booster circuit unit to a lighting fixture or the like.
JP 2001-357986 A

  At present, particularly in notebook computers, the booster circuit unit is often adhered and fixed to the inner surface of the housing with a double-sided adhesive tape. The booster circuit unit to be bonded and fixed is not provided with a configuration for positioning, and the mounting position with respect to the housing is likely to vary. If the mounting position of the booster circuit unit deviates from the predetermined position, the cable for connecting the fluorescent tube or the battery will not reach the booster circuit unit, or the assembly will be hindered such that a space for storing the cable cannot be secured. There is a risk of it coming.

  Further, in Patent Document 1, the case main body 114 is provided with the mounting hole 114a and the mounting notch 114b. If, for example, a convex portion that engages with these is provided in the housing, the booster circuit is engaged by the engagement of both. The unit can be positioned in the housing. However, in Patent Document 1, a mounting body 114a and a mounting notch 114b are provided in a case main body 114 made of a hard steel plate, and mechanical stresses such as twists and warps that act on the housing are caused by the positioning projections and It is easy to be transmitted to the circuit board through the case body 114. When a stress such as twisting or warping acts on the circuit board, the circuit board itself or a solder joint portion or wiring pattern of a mounted component is damaged. In particular, since the circuit board of the booster circuit unit has a high voltage generator such as a transformer, the action of mechanical stress is not preferable.

  For example, in a notebook computer, a booster circuit unit is generally arranged on the liquid crystal display device side. And since the notebook computer has a structure in which the liquid crystal display device side is opened and closed by hand, there is a twist and warp in the case when opening and closing, together with recent promotion of thinning. It tends to occur.

  The present invention has been made in view of the above-described problems, and the object of the present invention is to make it possible to accurately attach to the casing, and to make it difficult for external force applied to the casing to be applied to the booster circuit and the circuit board on which the booster circuit is formed. An object of the present invention is to provide a booster circuit unit and an electronic device including the same.

  The booster circuit unit of the present invention includes a circuit board on which a booster circuit is formed, and a flexible resin insulating case fixed to the circuit board so as to cover the circuit board. An engaging portion for positioning with respect to the electronic device casing is provided.

  The electronic device of the present invention includes a circuit board on which a booster circuit is formed, and a booster circuit unit including a flexible resin insulating case fixed to the circuit board so as to cover the circuit board, A housing to which the booster circuit unit is attached, an engaging portion for positioning with respect to the housing is provided in the insulating case, and a portion of the housing to which the booster circuit unit is attached is engaged with the engaging portion provided in the insulating case. It is characterized in that an engaged portion that can be engaged is provided.

  The booster circuit formed on the circuit board has a function of boosting and outputting an input voltage. An insulating case provided so as to cover the circuit board has a function of insulating the circuit board (including a booster circuit formed thereon) from an external conductive portion.

  Since the insulating case is provided with an engaging portion for positioning, the booster circuit unit inevitably becomes a predetermined portion of the casing by engaging the engaging portion with the engaged portion provided in the casing. It is constrained to the position (position where the booster circuit unit should be properly attached), and the booster circuit unit can be accurately positioned and attached to the housing.

  Since the insulating case provided with the engaging portion is made of a flexible resin material, the insulating case absorbs stress caused by twisting and warping of the casing acting via the engaged portion, and the circuit board. (Or reduction). That is, even if an excessive force is applied to the positioning engaging portion via the engaged portion, the insulating case including the engaging portion is flexibly deformed to absorb the stress received from the engaged portion. The influence of stress on the circuit board can be reduced.

  In addition, from the viewpoint of surely preventing the engaged portion that engages with the engaging portion from colliding with the circuit board and the components mounted thereon, the engaging portion is from a portion that covers the circuit board in the insulating case. In addition, it is preferable to provide in an extended portion that extends and extends into a region that does not overlap the circuit board. Thereby, the reliability of a circuit board can be improved more.

  If the extension portion is not fixed to the housing and the engaged portion, the extension portion does not follow the twist or warp of the housing, the inclination of the engaged portion, etc. It is hard to be affected by. Therefore, the stress can hardly be applied to the circuit board from the extended portion.

  Further, if at least one of the position, number, dimension, and shape of the engaging portion is made different for each type of circuit board, the type (function, Performance and manufacturer). In order to enable this identification, it is necessary that the degree of difference in the position, size, and shape of the engaging portion can be easily recognized by a person. The housing of the electronic device to which the booster circuit unit is attached is provided with engaged portions corresponding to the position, number, size, and shape of the respective engaging portions. Engagement with the joint portion becomes impossible, and it is possible to prevent a booster circuit unit of a type that should not be originally attached from being erroneously attached. This also makes it possible to correctly mount the booster circuit unit together with the positioning described above.

  According to the booster circuit unit of the present invention, since the engaging portion provided in the flexible resin insulating case is used as a positioning member, the booster circuit unit can be accurately positioned with respect to the housing. In addition, the circuit board can be protected from external stress caused by twisting and warping of the casing, and the reliability of the circuit board and the booster circuit formed thereon can be improved.

  According to the electronic apparatus of the present invention, since the booster circuit unit is attached to the housing using the engaging portion provided in the flexible resin insulating case as a positioning member, the booster circuit unit is mounted on the housing. Therefore, the circuit board can be protected from external stress caused by twisting or warping of the housing. Thereby, the assembly property and reliability of an electronic device can be improved.

[First Embodiment]
FIG. 1 shows an electronic device 100 according to this embodiment. The electronic device 100 is, for example, a notebook computer, and a main body 105 and a liquid crystal display device 101 are connected via a hinge 103. The liquid crystal display device 101 can be opened and closed with respect to the main body 105. The main body 105 includes a keyboard 104, a motherboard, a hard disk device, an optical disk device, and the like. The liquid crystal display device 101 includes a liquid crystal display panel 102, a backlight unit, and drivers for these.

  FIG. 2 shows a state in which the bezel 106 that covers the edge of the liquid crystal panel 102 is removed from the liquid crystal display device 101 shown in FIG. For example, a cold cathode tube (not shown) is incorporated in the lower edge of the liquid crystal panel 102 as a light source for illuminating the liquid crystal panel 102. In a space on the inner surface of the housing 14 secured below the lower edge portion, a booster circuit unit 1 for lighting a cold cathode tube is disposed. As will be described later, the booster circuit unit 1 is positioned at a predetermined position and fixed to the inner surface of the housing 14 by bonding or screwing.

  A locking member (not shown) for locking / releasing the main body 105 in the closed state is disposed in a space secured above the upper edge of the liquid crystal panel 102.

  FIG. 3 is an exploded perspective view of the booster circuit unit 1 according to the present embodiment. The booster circuit unit 1 is formed by combining a circuit board 3 on which a booster circuit is formed and an insulating case 2.

  The circuit board 3 is formed by forming a booster circuit on a rectangular printed wiring board 4. The booster circuit includes a piezoelectric transformer 19 mounted on the printed wiring board 4, a coil 18, a control IC 17, other components, wiring for connecting these components, and the like. In addition, connectors 16 and 20 are mounted on the printed wiring board 4 at both ends in the longitudinal direction.

  The piezoelectric transformer 19 which is a main component of the booster circuit raises the voltage of the battery provided in the main body 105 to a voltage necessary for lighting the cold cathode tube. A winding transformer may be used instead of a piezoelectric transformer, but the piezoelectric transformer is made of a thin ceramic plate, so it is not thick and small, lightweight, consumes little power, does not generate noise, and does not generate heat. It has an excellent point and is suitable for use in a liquid crystal display device of a notebook computer. The control IC 17 converts the DC voltage from the battery into an AC voltage, and controls the voltage and current applied to the cold cathode tube.

  The insulating case 2 is made of a flexible resin material. For example, it is made of polyester, polycarbonate, or other PET (polyethylene terephthalate) resin material and is translucent. The insulating case 2 is assembled from the sheet state shown in FIG. 5 into the rectangular tube shape shown in FIG.

  The insulating case 2 is formed by integrally molding a bottom plate portion 7a, two side plate portions 7b and 7c, a top plate portion 7d, an extending portion 9, and a pasting portion 7e (see FIG. 5). The bottom plate portion 7a, the side plate portions 7b and 7c, the top plate portion 7d, the extending portion 9, and the pasting portion 7e all have a rectangular shape. One surface of the bottom plate portion 7a functions as a circuit board fixing surface to which the circuit board 3 is fixed, and the other surface which is the back surface functions as an adhesive surface to the inner surface of the housing 14. The extending portion 9 is integrally provided on one side of the short side of the bottom plate portion 7a, and extends in the longitudinal direction of the bottom plate portion 7a.

  The extending portion 9 is provided with an engaging portion 5 for positioning the booster circuit unit 1 with respect to the inner surface of the casing 14 described above. In the present embodiment, the engaging portion 5 is a round hole that penetrates the extending portion 9. The engaging part 5 is provided in the approximate center of the extending part 9.

  The insulating case 2 is folded along the alternate long and short dash line from the sheet state shown in FIG. 5, and is assembled into a rectangular tube shape shown in FIG. A method such as a double-sided pressure-sensitive adhesive tape, an adhesive, or welding can be employed for bonding the top plate portion 7d and the pasting portion 7e.

  The circuit board 3 is inserted into a space surrounded by the bottom plate portion 7a, the side plate portions 7b and 7c, and the top plate portion 7d, and the surface opposite to the mounting surface of the components 16 to 20 is connected to the top plate portion 7d in the bottom plate portion 7a. It is bonded and fixed to the opposing surface (the circuit board fixing surface described above). For this adhesion, for example, a double-sided adhesive tape or an adhesive is used.

  The planar dimension of the circuit board 3 is slightly smaller than the planar dimension of the bottom plate part 7 a, and the circuit board 3 does not overlap the engaging part 5 provided in the extending part 9. The components 16 to 20 of the circuit board 3 do not contact the top plate portion 7d of the insulating case 2 but are opposed to the top plate portion 7d with a gap. The top plate portion 7d covers almost all of the parts 16 to 20 mounting surface (boost circuit forming surface) of the circuit board 3. As described above, since the circuit board 3 is covered so as to be wrapped in the rectangular tube-shaped insulating case 2, the circuit board 3 including the booster circuit and the conductive portion around the mounting position of the booster circuit unit 1 are arranged. Short circuit between can be prevented.

  As shown in FIG. 4A, an engaged portion 12 that can be engaged with the engaging portion 5 provided in the insulating case 2 is provided at a location where the booster circuit unit 1 is attached on the inner surface of the housing 14. ing. The engaged portion 12 is a columnar protrusion that protrudes perpendicularly to the inner surface of the housing 14. The outer diameter of the engaged portion 12 is slightly smaller than the inner diameter of the engaging portion 5. The protruding length of the engaged portion 12 is larger than the thickness of the engaging portion 5 and the extending portion 9 provided with the engaging portion 5.

  When attaching the booster circuit unit 1 to the inner surface of the housing 14, the engaging portion 5 provided on the insulating case 2 of the booster circuit unit 1 is engaged with the engaged portion 12 provided on the inner surface of the housing 14. That is, the engaged portion 12 that is a protrusion is inserted into the engaging portion 5 that is a round hole. There is some play between the inner peripheral surface of the engaging portion 5 and the outer peripheral surface of the engaged portion 12.

  As described above, the booster circuit unit 1 can be easily and accurately positioned at a predetermined position on the inner surface of the housing 14. In the positioned state, the back surface of the bottom plate portion 7a of the insulating case 2 (the surface opposite to the surface to which the circuit board 3 is bonded) is bonded and fixed to the inner surface of the housing 14. This adhesion is performed using a double-sided adhesive tape, an adhesive, or the like. Since the bottom plate portion 7a of the insulating case 2 is interposed between the circuit board 3 and the inner surface of the casing 14, even if the casing 14 is made of metal, a short circuit between the casing 14 and the circuit board 3 can be prevented.

  As shown in FIG. 2, the connector 16 on the circuit board 3 is connected to the cable 21 connected to the battery provided in the main body 105, and the connector 20 is built in the lower edge of the liquid crystal panel 102. A cable 22 connected to the electrode of the cold cathode tube is connected. At this time, since the booster circuit unit 1 is accurately positioned as described above, the cables 21 and 22 do not reach the connectors 16 and 20 and cannot be connected, and the end of the booster circuit unit 1 and the hinge 103 are not connected. It is possible to avoid the fact that the space (distance) between the cables becomes small and the cables 21 and 22 cannot be accommodated in the space.

  When the liquid crystal display device 101 is opened / closed with respect to the main body 105, mechanical stress such as twisting and warping is likely to occur in the housing 14 due to the recent progress of thinning. When the casing 14 is twisted or warped, the engaged portion 12 provided on the inner surface of the casing 14 is displaced with respect to the engaging portion 5, or is almost aligned with an axis passing through the center of the engaging portion 5. There is a possibility that stress may be exerted on the engaging portion 5 by, for example, tilting from a state of penetrating the engaging portion 5 in parallel.

  However, in this embodiment, since the insulating case 2 is made of a flexible resin material, the insulating case 2 absorbs stress caused by twisting or warping of the housing 14 acting via the engaged portion 12. Thus, it is possible not to reach the circuit board 3 (or to reduce it). That is, even if an excessive force is applied to the engaging portion 5 via the engaged portion 12, the engaging portion 5 and the extending portion 9 provided with the engaging portion 5 are flexibly deformed so that the engaged portion 12 The stress received is absorbed, and the influence of the stress on the cylindrical portion housing the circuit board 3 can be reduced. As a result, the circuit board 3 and the booster circuit formed on the circuit board 3 can be protected from external stress caused by twisting and warping of the casing 14, and failure and malfunction can be prevented and reliability can be improved. In particular, the booster circuit outputs a high voltage of 1000 V or more at the start of lighting of the cold-cathode tube, and outputs several hundred volts even in a steady state. Therefore, increasing the reliability leads to an increase in safety.

  The engaging portion 5 extends outward from the end portion of the circuit board 3 instead of the bottom plate portion 7a, the side plate portions 7b and 7c, and the top plate portion 7d, which are portions covering and covering the circuit board 3. Since it is provided in the extension part 9 which is a part, it can prevent reliably that the to-be-engaged part 12 which penetrates the engaging part 5 collides with the circuit board 3 and the components mounted in this. That is, even if the engaged portion 12 is inclined due to the twist or warp of the housing 14, the contact with the components can be prevented. This also ensures high reliability of the circuit board 3 and the booster circuit formed thereon.

  Since the back surface of the bottom plate portion 7a of the insulating sheet 2 is bonded and fixed to the inner surface of the housing 14, the booster circuit unit 1 is mounted on the housing 14 when carrying the notebook computer or opening and closing the liquid crystal display device 101. To prevent it from moving. Thereby, generation | occurrence | production of an unpleasant vibration sound, a failure of components, and also the cables 21 and 22 can be prevented from getting entangled or ramped.

  Further, the circuit board 3 is fixed to the bottom plate portion 7a, and bonding the bottom plate portion 7a to the inner surface of the housing 14 eliminates the air between the bottom plate portion 7a and the housing 14 and closely contacts them. Thus, the heat generated from the circuit board 3 can be efficiently released to the housing 14. In particular, among the various components, the piezoelectric transformer 19 generates a relatively large amount of heat, and increasing the thermal conductivity from the circuit board 3 to the housing 14 is very effective for cooling the piezoelectric transformer 19.

  The extending portion 9 provided with the engaging portion 5 is not bonded to the housing 14. Further, the engaging portion 5 and the engaged portion 12 are engaged with a slight play. As described above, the extending portion 9 does not follow the twist or warp of the housing 14, the inclination of the engaged portion 12, etc., and is not easily affected by the force from them. Therefore, it is difficult for stress to reach the circuit board 3 from the extending portion 9.

  In this embodiment, the engaging case 5 for positioning is provided in the insulating case 2, and it is not necessary to provide such an engaging portion in the circuit board 3, so that a space for the engaging portion is provided in the circuit board 3. There is no need to secure. Accordingly, the density of the circuit board 3 is not hindered. In addition, the insulating case 2 obtained from a resin sheet is simpler because the sheet mold is cheaper and the sheet is softer than the case where the engaging portion for positioning is provided on the metal as in Patent Document 1 described above. You can punch through the mold and shorten the time to make it.

  Although the mounting position of the booster circuit unit 1 with respect to the housing may be determined at the end of the entire electronic device design, it is easy and short time to provide the positioning engaging portion 5 in the insulating case 2 as described above. This will not delay the process. Further, it is possible to easily and quickly cope with a change in the design of the engaging portion 5.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the same component as the said 1st Embodiment, and the detailed description is abbreviate | omitted.

  FIG. 6 shows a booster circuit unit 26 as a comparative example for the present embodiment. In this booster circuit unit 26, a positioning hole is formed in the circuit board 27, and the engaged portion 12 provided on the inner surface of the housing 14 is inserted into the hole, whereby the booster circuit unit 26 is formed in the housing 14. Positioned and attached to. A bottom plate portion of an insulating case 28 to which the circuit board 27 is bonded is interposed between the circuit board 27 and the inner surface of the housing 14.

  In recent years, there have been many cases where the case is made of a metal such as magnesium that is lighter and stronger than resin materials, but the booster circuit used to light the cold cathode tube handles high-frequency and high-voltage signals. If the metal casing 14 is near the circuit board 27 as in the comparative example, the leakage current flowing from the circuit board 27 to the casing 14 increases due to electrostatic coupling.

  Therefore, in this embodiment, as shown in FIG. 8, the circuit board 3 is bonded to the top plate portion 33 a facing the resin bezel 103 instead of the bottom plate portion 33 b bonded and fixed to the inner surface of the housing 14. Fixed. The extending portion 32 provided with the engaging portion 5 is provided integrally with the bottom plate portion 33b.

  As shown in FIG. 7, the insulating case 31 has a bottom plate portion 33b adhered and fixed to the inner surface of the housing 14, and the circuit board 3 has a resin bezel with the surface opposite to the component mounting surface sandwiching the top plate portion 33a. 106 is faced. The engaging portion 5 of the extending portion 32 provided integrally with the bottom plate portion 33b is engaged with the engaged portion 12 provided on the inner surface of the housing 14 in the same manner as in the first embodiment, and is a booster circuit. The unit 1 is positioned at a predetermined position.

  In the present embodiment, since the engaging portion 5 for positioning with respect to the housing 14 is not provided on the circuit board 3, it is not necessary to engage the circuit board 3 and the housing 14, and the circuit board 3 is as shown in FIG. The resin can be positioned on the bezel 106 side. Thereby, the insulation between the circuit board 3 and the metal housing 14 can be improved, and the leakage current from the circuit board 3 to the housing 14 can be suppressed. Further, it is possible to increase the distance between the circuit board 3 and the housing 14 without increasing the distance between the housing 14 and the bezel 106 only by turning the booster circuit unit upside down.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. Also in this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  For example, the circuit board of a booster circuit unit that is widely used for turning on the light source of a backlight of a notebook computer has a standardized outer shape in consideration of cost reduction and productivity, and is of a different type. At present, the appearance is almost the same. By changing the circuit constants and part of the wiring pattern of components on the circuit board, the functions and performance are varied. In that case, since they are apparently similar circuit boards, they are distinguished by marking or sticking them to distinguish them, but this is only easy for the operator to distinguish, and the operator can make a mistake. For example, it may happen that it is mistakenly attached to a model different from the model that should be installed.

  In order to prevent such erroneous mounting, in the present embodiment, the type (function, performance, manufacturer difference) of the circuit board is identified (discriminated) from the position, number, size, shape, etc. of the positioning engaging portion described above. ) I was able to do it.

  Specific examples of the insulating case in which the position, number, size, shape, and the like of the engaging portion are varied depending on the type of the circuit board are shown in FIGS.

  In the insulating case 42 shown in FIG. 10, two engaging portions 44 a and 44 b are provided on the extending portion 43. Each engaging part 44a, 44b is a round hole having the same inner diameter. The engaging portions 44 a and 44 b are juxtaposed along the short direction so that a line connecting the centers thereof is parallel to the short direction of the insulating case 42.

  In the insulating case 51 shown in FIG. 11, two extending portions 53 a and 53 b are provided on the extending portion 52. The engaging portions 53a and 53b are both round holes, but the inner diameter of the engaging portion 53a is larger than the inner diameter of the engaging portion 53b. The engaging portions 53 a and 53 b are arranged in parallel along the longitudinal direction so that the line connecting the centers thereof is parallel to the longitudinal direction of the insulating case 42.

  In the insulating case 58 shown in FIG. 12, one engaging portion 60 is provided in the approximate center of the extending portion 59. The engaging portion 60 is a square hole having a rectangular shape in plan view that penetrates the extending portion 59.

  Different types of circuit boards A, B, and C are combined with the above-described insulating cases 42, 51, and 58, respectively. The types of the circuit boards A, B, and C can be identified from the engaging portions provided in the insulating cases 42, 51, and 58.

  That is, it can be seen that the circuit board included in the booster circuit unit is the circuit board A from the engaging portions 44a and 44b provided as two round holes having the same inner diameter arranged in parallel in the short direction of the insulating case. In addition, it can be seen from the engagement portions 53a and 53b provided as two round holes with different inner diameters arranged side by side in the longitudinal direction of the insulating case that the circuit board included in the booster circuit unit is the circuit board B. Further, it can be seen from the engagement portion 60 provided as one square hole that the circuit board included in the booster circuit unit is the circuit board C.

  And the to-be-engaged part corresponding to the position, number, dimension, and shape of each engaging part is provided in the housing | casing of the electronic device to which each booster circuit unit is attached.

  In the example shown in FIG. 10, two columnar engaged portions 45a and 45b having the same outer diameter are provided in the booster circuit unit mounting portion in the housing, and the engaged portions 45a and 45b are engaged portions. Only engagement with 44a, 44b is allowed. That is, the engaged parts 45a and 45b cannot be engaged with the engaging parts 53a and 53b shown in FIG. 11 because their positions and dimensions do not correspond to each other, and the engaged parts 60 shown in FIG. , And the shape does not correspond and cannot be engaged. As a result, the operator is mistakenly provided with the booster circuit unit having the insulating case 51 of FIG. 11 or the insulating case 58 of FIG. 12 in the model to which the booster circuit unit having the insulating case 42 of FIG. If you try to install a booster circuit unit, you cannot install it. Thereby, the mismatched mounting | wearing with an electronic device and a pressure | voltage rise circuit unit can be prevented reliably.

  Similarly, in the example shown in FIG. 11, two columnar engaged portions 54a and 54b having different outer diameters are provided in the booster circuit unit mounting portion in the housing, and the engaged portions 54a and 54b are Only engagement with the engaging portions 53a and 53b is allowed. That is, the engaged portions 54a and 54b cannot be engaged with the engaging portions 44a and 44b shown in FIG. 10 because their positions and dimensions do not correspond to each other, and the engaged portions 60 shown in FIG. , And the shape does not correspond and cannot be engaged. Accordingly, the operator should mistakenly include the booster circuit unit including the insulating case 42 of FIG. 10 or the insulating case 58 of FIG. 12 in the model to which the booster circuit unit including the insulating case 51 of FIG. 11 is to be attached. If you try to install a booster circuit unit, you cannot install it. Thereby, the mismatched mounting | wearing with an electronic device and a pressure | voltage rise circuit unit can be prevented reliably.

  Similarly, in the example shown in FIG. 12, one prismatic engaged portion 61 b is provided in the booster circuit unit mounting portion in the housing, and this engaged portion 61 is only engaged with the engaging portion 60. Is acceptable. That is, the engaged portion 61 cannot be engaged with the engaging portions 44a and 44b shown in FIG. 10 because the position, number, size, and shape do not correspond to each other, and the engaged portion 61 cannot be engaged with the engaging portions 53a and 53b shown in FIG. The numbers, dimensions, and shapes do not correspond and cannot be engaged. Accordingly, the operator should mistakenly include the booster circuit unit having the insulating case 42 of FIG. 10 or the insulating case 51 of FIG. 11 in the model to which the booster circuit unit having the insulating case 58 of FIG. If you try to install a booster circuit unit, you cannot install it. Thereby, the mismatched mounting | wearing with an electronic device and a pressure | voltage rise circuit unit can be prevented reliably.

  Note that the positions, numbers, dimensions, and shapes of the engaging portions shown in FIGS. 10 to 12 are examples, and other engaging portions having various positions, numbers, sizes, and shapes can be employed.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. Also in this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 9 shows an insulating case 36 according to this embodiment. As in the first embodiment, the circuit board is bonded and fixed to the bottom plate portion 39a. In the present embodiment, two extending portions 37a and 37b are provided. The extending portion 37a is integrally provided on one side of the short side of the bottom plate portion 39a via a perforated easily breakable line portion 38, and extends in the longitudinal direction (left side in FIG. 9) of the bottom plate portion 39a. ing. The extending portion 37b is integrally provided on the other short side of the bottom plate portion 39a via the perforated easily breakable line portion 38, and extends in the longitudinal direction of the bottom plate portion 39a (right side in FIG. 9). It is extended.

  Each extending portion 37a, 37b is provided with an engaging portion 5 for positioning the booster circuit unit with respect to the inner surface of the housing 14 described above. The engaging part 5 is a round hole penetrating each extending part 37a, 37b as in the first embodiment.

  When the booster circuit unit needs to be replaced after the booster circuit unit is bonded to the housing, for example, because the wrong type of booster circuit unit has been attached. The insulation case must be peeled from the housing. Since the circuit board is bonded and fixed to the insulating case, an excessive force is easily applied to the circuit board when the insulating case is peeled off from the housing, and the circuit board and the booster circuit formed thereon may be damaged.

  Therefore, in this embodiment, in the insulating case 36 shown in FIG. 9, the bottom plate portion 39a to which the circuit board is bonded and fixed is not bonded to the inner surface of the housing, but only the extending portions 37a and 37b are bonded to the inner surface of the housing. Thus, the booster circuit unit is fixed to the casing.

  When reworking, the easily breakable line portion 38 is broken to separate the cylindrical portion of the insulating case 36 including the bottom plate portion 39a from the extending portions 37a and 37b. Since this portion is not bonded to the inner surface of the casing, it can be easily removed from the casing without applying excessive force to the circuit board.

  When the extending portions 37a and 37b remaining on the inner surface of the casing are peeled off, the circuit board has already been removed from the casing. Therefore, when the extending portions 37a and 37b are peeled off from the casing, There is no excessive force. Thereby, a circuit board is not damaged at the time of rework.

  The easily breakable line portion 38 is not limited to the perforation, and may be any configuration that can easily separate the extending portions 37a, 37b and the cylindrical portion by the operator's hand. For example, the extending portion 37a , 37b and a bottom plate portion 39a may be provided with a groove having a V-shaped cross section.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. Also in this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 13A shows a booster circuit unit 65 and an insulating case 66 according to this embodiment. In this embodiment, the positioning engaging portion provided in the extending portion 9 is different from that in the first embodiment. That is, the engaging portion 67 in the present embodiment is provided as a cut piece formed by cutting the extending portion 9. Specifically, as shown in FIG. 13A, the engaging portion 67 has a quadrangular shape, and only one edge portion 67a is connected to the extending portion 9, and along the edge portion 67a so as to protrude downward. It is bent.

  An engaged portion 68 that can be engaged with the engaging portion 67 is provided on the inner surface of the housing 14 where the booster circuit unit 65 is attached. The engaged portion 68 protrudes perpendicularly to the inner surface of the housing 14 and has a recess 68a into which the engaging portion 67 can be inserted.

  When attaching the booster circuit unit 65 to the inner surface of the casing 14, the engaging portion 67 provided on the insulating case 66 of the booster circuit unit 65 is engaged with the engaged portion 68 provided on the inner surface of the casing 14 ( FIG. 13B). That is, both engage with each other so that the engaging portion 67 is inserted into the recess 68 a of the engaged portion 68.

  Thereby, the booster circuit unit 65 can be easily and accurately positioned at a predetermined position on the inner surface of the housing 14. Further, the engaging portion 67 is cantilevered by the extending portion 9 with its edge portion 67 a, and the engaged portion 67 is inserted in the recess 68 a of the engaged portion 68. Even if a force is received from 68, it can swing around the edge portion 67 a, and the force applied from the engaged portion 68 can be absorbed by the swing so as not to reach the circuit board 3. In addition, the engaging portion 67 is not provided additionally to the extending portion 9 as a separate body, but the extending portion 9 is notched and simply bent so that it can be easily manufactured.

  As mentioned above, although each embodiment of this invention was described, of course, this invention is not limited to these, A various deformation | transformation is possible based on the technical idea of this invention.

  In each of the above embodiments, the booster circuit unit is fixed to the casing by adhering the insulating case to the inner surface of the casing. However, the booster circuit unit may be fixed to the casing by screwing as shown in FIG. Good. That is, as shown in FIG. 14A, a cylindrical engaged portion 71 having a screw hole formed therein is provided on the inner surface of the casing to which the booster circuit unit is attached, and the engaging portion 5 is connected to the engaged portion 71. After positioning in the screw hole, the screw 72 is screwed into the screw hole as shown in FIG. 14B to fix the booster circuit unit to the housing. Screwing allows the step-up circuit unit to be removed without applying excessive force to the circuit board as compared to fixing by bonding.

  In addition, the cylindrical part which threaded the outer peripheral part as an engaged part is provided, the front end side of the engaged part is protruded from the engaging part 5 having a round hole shape, and a nut is attached to the protruding part. The booster circuit unit may be fixed to the casing by screwing. Alternatively, a cap made of resin or rubber is press-fitted onto a portion of the engaged portion protruding from the engaging portion 5 so as to be inserted, and the extending portion 9 is sandwiched between the lower end portion of the cap and the inner surface of the housing. The booster circuit unit may be fixed to the housing with

  Moreover, even if it is the combination of a round hole-shaped engaging part and a column-shaped engaged part like the said 1st Embodiment, they do not have play between both, but the to-be-engaged part The boosting circuit unit may be fixed to the casing by fitting the engaging portion to the casing. In this case, as shown in FIG. 15, if a slit 77 extending in the radial direction from the edge portion is formed in the round hole-shaped engaging portion 76, the engaging portion is engaged when the engaging portion 76 is inserted into and removed from the engaged portion. 76 can be slightly widened, and can be easily inserted and removed. Further, the slit 77 increases the amount of elastic deformation in the engaging portion 76 and enhances the action of absorbing the force applied from the engaged portion.

  FIG. 16 shows an example in which the engaging portion 81 is provided on the bottom plate portion 82 b of the insulating case 80. The engaging portion 81 is provided as a round hole that penetrates the bottom plate portion 82b. The circuit board is bonded and fixed to the top plate portion 82a facing the bottom plate portion 82b.

  A booster circuit unit 83 in which the circuit board 3 is combined with the insulating case 80 is attached to the housing 14 as shown in FIG. That is, the step-up circuit unit 83 is positioned by inserting the columnar engaged portion 84 provided on the inner surface of the housing 14 into the engaging portion 81 provided on the bottom plate portion 82b, and the bottom plate portion 82b is attached to the housing. It is bonded and fixed to the inner surface of the body 14. The engaging portion 81 is provided at a position where no component is mounted on the circuit board 3 or a mounting position of a component having a relatively low height. Even if the engaged portion 84 is inserted into the engaging portion 81, the engaged portion 81 is covered. The engaging portion 84 is prevented from hitting the part.

  Since the circuit board 3 is bonded to the top plate portion 82a, the circuit board 3 can be positioned on the resin bezel 106 side. Thereby, even if the housing | casing 14 is metal, the insulation between the circuit board 3 and the housing | casing 14 can be improved, and the leakage current from the circuit board 3 to the housing | casing 14 can be suppressed.

  Further, as an attachment structure in which the distance between the circuit board 3 and the metal housing 14 is increased from the viewpoint of suppressing the leakage current, it may be as shown in FIG. That is, as the engaged portion 89 provided on the inner surface of the housing 14, a stepped boss including a small diameter portion 89 a and a large diameter portion 89 b is provided, and only the small diameter portion 89 a is provided on the extending portions 9 a and 9 b of the insulating case 88. It penetrates through the provided round hole-shaped engaging portion.

  Therefore, (the outer diameter of the small diameter portion 89a) <(the inner diameter of the engaging portion) <(the outer diameter of the large diameter portion 89b). The extending portions 9 a and 9 b are provided so as to extend from both end portions of the circuit board 3. The booster circuit unit 87 is attached to the housing 14 such that the extending portions 9a and 9b are placed on the upper surface of the large diameter portion 89b. Thus, a gap can be secured between the bottom plate portion of the insulating case 88 to which the circuit board 3 is fixed and the housing 14 by the height of the large diameter portion 89b, and the housing 14 is made of metal. However, the insulation between the circuit board 3 and the housing 14 can be improved, and the leakage current from the circuit board 3 to the housing 14 can be suppressed.

  FIG. 19 shows an insulating case 91 in which an extending portion 92 is provided with an engaging portion 93 as a U-shaped notch. FIG. 20 shows an insulating case 94 in which the distal end portion of the projecting extending portion 95 is an engaging portion 95a, and the engaging portion 95a is opened in the lateral direction of the engaged portion 96 provided in the housing. Positioning is performed by inserting it into the empty space from the side. In the insulating case 97 shown in FIG. 21, an extending portion 98 extending in the short direction of the insulating case 97 from a portion surrounding the circuit board in the insulating case 97 is provided, and a round hole-like engaging portion is provided in the extending portion 98. 5 is provided.

  The combination of the engaging portion and the engaged portion is not limited to the combination of a round hole and a cylinder, and may be a combination of a square hole and a prism. In this case, it is possible to prevent the booster circuit unit from rotating around the engaged portion and perform positioning with higher accuracy. Even if it is a combination of a round hole and a cylinder, the rotation of the booster circuit unit can be prevented if two or more sets are provided.

  The booster circuit unit of the present invention can be used not only for lighting a cold cathode tube but also for lighting a hot cathode tube. Furthermore, since a relatively high voltage is required not only for the fluorescent tube but also for emitting a large number of light emitting diodes connected in series, the booster circuit unit of the present invention can be used also in that case.

  The electronic apparatus of the present invention is not limited to the notebook computer shown in the above embodiment, but a liquid crystal display device, a PDA (Personal Digital Assistant), a portable video player in which the main body and the liquid crystal display device are integrated, and car navigation. An example is a system.

It is a perspective view of the electronic device which concerns on embodiment of this invention. It is a figure which shows the inside of the liquid crystal display device shown in FIG. 1 is an exploded perspective view of a booster circuit unit according to a first embodiment of the present invention. It is a perspective view which shows the attachment structure with respect to the electronic device housing | casing of the voltage booster circuit unit shown in FIG. FIG. 4 is a development view of an insulating case of the booster circuit unit shown in FIG. 3. It is a schematic cross section which shows the attachment structure with respect to the electronic device housing | casing of the booster circuit unit by a comparative example. It is a schematic cross section which shows the attachment structure with respect to the electronic device housing | casing of the booster circuit unit which concerns on the 2nd Embodiment of this invention. FIG. 8 is a perspective view of an insulating case of the booster circuit unit shown in FIG. 7. It is a perspective view of the insulation case of the booster circuit unit which concerns on the 4th Embodiment of this invention. It is a perspective view of the insulation case of the booster circuit unit which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows the other example of the insulation case which concerns on the 3rd Embodiment. It is a perspective view which shows the other example of the insulation case which concerns on the said 3rd Embodiment. It is a schematic cross section which shows the attachment structure with respect to the electronic device housing | casing of the booster circuit unit which concerns on the 5th Embodiment of this invention. It is a schematic cross section which shows the modification of the attachment structure with respect to the electronic device housing | casing of a pressure | voltage rise circuit unit. It is a perspective view which shows the modification of an insulating case. It is a perspective view which shows the modification of an insulating case. FIG. 17 is a schematic cross-sectional view showing a structure for attaching a booster circuit unit including the insulating case shown in FIG. 16 to an electronic device casing. It is a schematic cross section which shows the modification of the attachment structure with respect to the electronic device housing | casing of a pressure | voltage rise circuit unit. It is a perspective view which shows the modification of an insulating case. It is a perspective view which shows the modification of an insulating case. It is a perspective view which shows the modification of an insulating case. It is a disassembled perspective view of the booster circuit unit of a prior art example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Boost circuit unit, 2 ... Insulation case, 3 ... Circuit board, 4 ... Printed wiring board, 5 ... Engagement part, 7a ... Fixed part, 9 ... Extension part, 12 ... Engagement part, 14 ... Housing 30 ... Boost circuit unit, 31 ... Insulating case, 36 ... Insulating case, 42 ... Insulating case, 44a, 44b ... Engagement part, 51 ... Insulating case, 53a, 53b ... Engaging part, 58 ... Insulating case, 60 ... Engagement part 65 ... Boost circuit unit 66 ... Insulation case 67 ... Engagement part 75 ... Insulation case 76 ... Engagement part 80 ... Insulation case 81 ... Engagement part 83 ... Boost circuit unit 87 DESCRIPTION OF SYMBOLS Boosting circuit unit 88 ... Insulating case 91 ... Insulating case 93 ... Engaging part 94 ... Insulating case 95a ... Engaging part 97 ... Insulating case 100 ... Electronic device 101 ... Liquid crystal display device

Claims (7)

A circuit board on which a booster circuit is formed;
It consists of a flexible resin insulating case fixed to the circuit board so as to cover the circuit board,
A booster circuit unit, wherein the insulating case is provided with an engaging portion for positioning with respect to the electronic device casing. 2. The booster circuit unit according to claim 1, wherein the insulating case has an extending portion that extends from a portion that covers the circuit board, and the engaging portion is provided in the extending portion. At least one of the position, the number, the size, and the shape of the engagement part is made different for each type of the circuit board so that the type of the circuit board can be identified from the engagement part. The booster circuit unit according to claim 1. A booster circuit unit comprising a circuit board on which a booster circuit is formed, and a flexible resin insulating case fixed to the circuit board so as to cover the circuit board;
An electronic device including a casing to which the booster circuit unit is attached,
The insulating case is provided with an engaging portion for positioning with respect to the housing,
An electronic device, wherein an engaged portion that can be engaged with the engaging portion is provided in a portion of the housing to which the booster circuit unit is attached. The electronic device according to claim 4, wherein the insulating case has an extending portion that extends from a portion that covers the circuit board, and the engaging portion is provided in the extending portion. The electronic device according to claim 5, wherein the extending portion is not fixed to the housing and the engaged portion. In order to identify the type of the circuit board from the engagement portion, at least one of the position, the number, the size, and the shape of the engagement portion is made different for each type of the circuit board,
The position, number, size, and shape of the engaged portion are made to correspond to the position, number, size, and shape of the engaging portion to be engaged with the engaged portion. The electronic device as described in.

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