JP2006196517A - Packaging method of electronic component and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a packaging method of an electronic component for realizing reduction in size of a device by reducing thermal stress to a weak heat component without using a heat dissipation member and performing free layout while taking account of various problems including circuit function and noise, and to provide an electronic apparatus. <P>SOLUTION: The lead 55 of a switching element in an inverter circuit section is preformed to specific dimensions and tightened temporarily by means of a fixing screw 54 while being aligned with a tap hole 56 provided in the bottom face 59 of a case. Subsequently, the solder surface of a printed board 1 is arranged facing to the bottom face 59 of a case and the lead 55 is inserted into a through hole of the printed board 1. Thereafter, switching elements 36-53 are tightened to the bottom face 59 of a case from a switching element fixing hole 29 provided in the printed board 1 and secured in place before being soldered with the lead 55 from the component surface side of the printed board 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for mounting an electronic component mounted on a printed circuit board and an electronic device.

FIG. 4 shows a conventional example of an electronic component mounting structure in which a board set in which a heat generating component and other electronic components are mounted on the same printed board is housed in a case.
In FIG. 4, switching elements 71 to 73 that are heat generating components are mounted on a heat radiating plate 74 that is a heat radiating member and mounted on a printed circuit board 70.
The hybrid IC 75 that is a low heat component is disposed adjacent to the switching elements 71 to 73 in the space surrounded by the heat sink 74 on the opposite surface to which the switching elements 71 to 73 are mounted, and is mounted on the printed circuit board 70.
Here, since the heat of the switching elements 71 to 73 is radiated through the heat radiating plate 74, the hybrid IC 75 is not subjected to the thermal stress from the switching elements 71 to 73, and further the heat of the choke coils 93 to 98 which are the surrounding heat generating components. Is also blocked by the heat sink 74. Therefore, the influence on the hybrid IC 75 that is a low heat component can be suppressed.
Furthermore, since the hybrid IC 75 that controls the switching elements 71 to 73 is disposed close to the switching elements 71 to 73, the wiring pattern between the hybrid IC 75 and the switching elements 71 to 73 is shortened, and the influence of noise can be reduced (for example, , See Patent Document 1).

Utility Model No. 2584522

However, in the conventional electronic component mounting structure, a large mounting space is required as a result of using a heat radiating member such as a heat radiating plate in order to release heat from the heat generating member. For this reason, the space for mounting other electronic components is limited, and a free layout that takes into account various problems such as circuit functions and noise is hindered, making it difficult to reduce the size of the product.
In particular, in a device that uses a large number of heat generating members, the space occupied by the heat radiating member is further increased in proportion to the number of the heat generating members, so that it has become more difficult to free layout and reduce the size of the device in consideration of various problems.

The present invention has been made in view of such problems, and reduces the thermal stress on low heat components without using a heat radiating member, and free layout in consideration of various problems such as circuit functions and noise. It is an object of the present invention to provide an electronic component mounting method and an electronic apparatus device that can realize downsizing of the device.

In order to solve the above problem, the present invention takes the following procedure.
The invention according to claim 1 is a mounting method of an electronic component in which a board set in which a heat generating component and other electronic components are mounted on the same printed circuit board is housed in a case, and the lead of the heat generating component is connected to the printed circuit board. And forming a tapped hole adapted to the mounting hole of the heat generating component on the bottom surface of the case, aligning the mounting hole of the heat generating component with the tap hole, and forming the heat generating component. The printed circuit board in which a hole is formed in a portion that is directly above the tap hole is stored in the case so that the solder surface faces the bottom surface of the case, and the printed circuit board is inserted through the hole in the printed circuit board. The heat generating component is finally tightened and fixed to the bottom surface of the case, and the lead of the heat generating component is soldered on the component surface of the printed circuit board.
According to a second aspect of the present invention, there is provided an electronic device device that houses a board set in which a heat generating component and other electronic components are mounted on the same printed circuit board in a case, and a mounting hole for the heat generating component on a bottom surface of the case. And a printed circuit board having a hole drilled in a portion that directly contacts the tap hole when stored in the case, and the lead of the heat generating component is a predetermined part of the printed circuit board. The heat generating component is temporarily tightened with its mounting hole aligned with the tapped hole, and the printed circuit board is placed on the temporarily tightened heat generating component. The solder surface is housed in the case so that it faces the bottom surface of the case, and the heat-generating component is fixed to the bottom surface of the case through a hole in the printed circuit board. Together with the said heat-generating components leads, characterized in that it is constructed by soldering at the component side of the printed circuit board.

  According to the electronic component mounting method and the electronic device apparatus of the present invention, the heat generated by the heat generating component can be radiated to the case body having a large heat radiating area without using a heat radiating member such as a heat radiating plate. Furthermore, a large mounting / space space occupied by the heat dissipating member can be used, and a free layout and miniaturization of the product in consideration of various problems such as circuit functions and noise can be realized. Further, the cost can be reduced by reducing the number of heat dissipating members.

  Hereinafter, examples of the present invention will be described with reference to FIGS.

FIG. 1 is a top view of a printed circuit board in an inverter device to which the electronic component mounting method of the present invention is applied. In FIG. 1, a printed circuit board 1 is roughly composed of a power supply circuit unit 2, a control circuit unit 3, and inverter circuit units 4-6.
The power supply circuit unit 2 receives electric power supplied from an external power supply (not shown) from the power supply connectors 22 and 23, converts the electric power into appropriate voltages and currents, and supplies them to the control circuit unit 3 and the inverter circuit units 4 to 6.
The control circuit unit 3 receives an external command (not shown) and outputs a command to the inverter circuit units 4 to 6.
The inverter circuit units 4 to 6 convert the direct current supplied from the power supply circuit unit 2 into alternating currents of various frequencies, and output them from the output connectors 24 to 26 to an electric motor (not shown) or the like. Switching elements 36 to 53 are used for this conversion, and the switch is repeatedly turned on and off at a high speed inside thereof, and heat is generated in accordance with the operation.

In FIG. 1, six switching elements 36 to 53 are grouped in each of the inverter circuit units 4 to 6.
FIG. 2 is an enlarged view of the periphery of a part of the switching elements of the inverter circuit section 4 of FIG. In FIG. 1 and FIG. 2, each switching element 36-53 is drawn with a broken line, but this is because the relays 7-13, electrolytic capacitors 14-19, etc. drawn with a solid line are the surface (component surface) of the printed circuit board 1. The switching elements 36 to 53 are arranged on the back surface (solder surface) side of the printed circuit board 1.

  3 is a cross-sectional view taken along line AA of FIG. 2 when the printed circuit board 1 is housed in a case of the electronic device. Two switching elements 38 and 41 are paired and arranged adjacent to each other on the solder surface 58 side of the printed circuit board 1, and are fixed to the case bottom surface 59 by mounting screws 54. As is apparent from FIG. 1, the other switching elements are also arranged in pairs, and are fixed to the case bottom surface 59 with mounting screws.

Hereinafter, a method for mounting the switching element will be described with reference to FIG.
First, a tapped hole 56 is formed in a predetermined position on the bottom surface 59 of the device case in advance.
The mounting holes of the switching elements 36 to 53 are aligned with the tap holes 56, and each switching element is temporarily fixed to the case bottom surface 59 by the mounting screw 54.
The printed circuit board 1 is placed in the case with the solder surface 58 facing down, and the leads 55 of the respective switching elements are inserted into the through holes 61 of the printed circuit board 1.
Since the printed circuit board 1 is provided with a hole 29 for attaching a switching element in a portion directly above the tap hole 56, a mounting screw 54 is tightened from above using a tool such as a screwdriver through this hole and temporarily fixed. Each switching element that has been fixed is fixed to the bottom surface 59 of the case.
By providing the mounting hole 29, the mounting screw 54 can be loosened even after the printed circuit board 1 is fixed to the bottom surface 59 of the case, and when the printed circuit board 1 is repaired or replaced. The printed circuit board 1 can be easily removed from the case.

When the printed circuit board 1 is stored in the case, the leads 55 of the respective switching elements are soldered on the component surface 57 side of the printed circuit board 1. The lead 55 of each switching element is formed with a predetermined dimension so that the switching element can be inserted into the through hole 61 on the printed circuit board 1 from the solder surface 58 side after the switching element is attached to the case bottom surface 59.

As described above, since the switching elements 36 to 53, which are heat generating components, are attached to the case bottom surface 59, the case itself becomes a heat radiating member, and heat generated by the switching element can be radiated without using a heat radiating plate or the like. .
In addition, by not using heat radiating members, there are no restrictions on the mounting position of components, and the layout and space of the product that take into account various problems such as circuit functions and noise using the mounting and space space occupied by the heat radiating members are reduced. Can be realized.

  In this embodiment, the switching element in the inverter device has been described as an example. However, the scope of application of the present invention is not limited to this, and the present invention can be applied to general electronic device devices having heat-generating components. Needless to say.

  The present invention can be widely applied to printed circuit boards on which electronic components are mounted.

Top view of a printed circuit board embodying the present invention 1 is an enlarged top view of a part of the printed circuit board of FIG. 2 is a cross-sectional view taken along the line AA of FIG. 2 when the printed circuit board of FIG. 1 is stored in the case of the electronic device. Top view of a printed circuit board using a conventional electronic component mounting structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Power supply circuit part 3 Control circuit part 4-6 Inverter circuit part 7-13 Relay 14-19 Electrolytic capacitor 20 Fuse 21 DC / DC converter 22, 23 Power supply connector 24-26 Output connector 27-35 Installation for switching elements Holes 36 to 53 Switching element 54 Mounting screw 55 Switching element lead 56 Tap 57 Component surface 58 Solder surface 59 Case bottom surface 60 Case side surface 61 Through hole 62 Solder 70 Printed circuit board 71 to 73 Switching element 74 Heat sink 75 Hybrid IC
76 Capacitor 77 Fuse 78 Line filter 79 Connector 80 Rectifier 81, 82 Capacitor 83-85 Resistor 86-88 Capacitor 89-92 Diode 93-98 Choke

Claims (2)

An electronic component mounting method for storing a board set in which a heat generating component and other electronic components are mounted on the same printed circuit board in a case,
Forming the lead of the heat generating component according to the position of a predetermined through hole of the printed circuit board,
Provide a tapped hole that fits the mounting hole of the heat generating component on the bottom surface of the case, align the mounting hole of the heat generating component with the tap hole, and temporarily tighten the heat generating component,
From above, the printed circuit board in which a hole is made in a portion that is directly above the tap hole is stored in the case so that the solder surface faces the bottom surface of the case,
The heat generating component is finally tightened and fixed to the bottom surface of the case through the hole of the printed board,
A method for mounting an electronic component, wherein the lead of the heat generating component is soldered on a component surface of the printed circuit board. In an electronic device device that houses a board set in which a heat generating component and other electronic components are mounted on the same printed circuit board,
A tapped hole provided on the bottom surface of the case in conformity with the mounting hole of the heat generating component;
A printed circuit board having a hole formed in a portion that directly hits the tap hole when stored in the case;
The lead of the heat generating component is formed in accordance with the position of a predetermined through hole of the printed circuit board, and the heat generating component is temporarily tightened with its mounting hole aligned with the tap hole,
The printed circuit board is stored in the case so that the solder surface faces the bottom surface of the case from above the heat-fitted component temporarily tightened,
The heat generating component is permanently fixed to the bottom surface of the case through a hole in the printed circuit board, and the lead of the heat generating component is soldered on the component surface of the printed circuit board. An electronic apparatus device characterized by the above.

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