JPH04133490A - Circuit board device - Google Patents

Abstract

PURPOSE:To protect a soldered part against damage so as to enhance a circuit board device in reliability by a method wherein a deformable bend is provided to the intermediate point of the lead of an electric component, where the bend concerned can be deformed corresponding to the displacement of the component relative to a board. CONSTITUTION:A bend 18 is provided to the intermediate point of the leads 15 of an electric component 13 which are filled or coated with curing insulating material 17, where the intermediate point concerned is located above a board 11 or on an electric component main body 14 side. The part of the lead 15 which extends vertically downward is made to protrude into a V-shaped form and set deformable corresponding to the displacement of the component 13 relative to the board 11. A hole 21 is provided to the board 11 at relative located under the main body 14 of the electric component 13 filled or coated with the curing insulating material 17. The hole 21 is formed large enough in diameter so as to enable the curing insulating material 17 to sag until it is set.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention relates to a circuit board device forming an electronic circuit such as an inverter for lighting a fluorescent lamp at high frequency, and in particular, It relates to applying or filling a solidifying insulating material on the surface where the main body of the component is located.

(Prior Art) For example, circuit board devices that form electronic circuits such as inverters for lighting fluorescent lamps at high frequencies are required to be miniaturized.
Mounting of electrical components on a board becomes denser. As described above, as the mounting density of electrical components increases and the distances between the electrical components decrease, there is a risk that electrical discharge may occur between the leads of these electrical components. Therefore, in order to prevent this, as shown in FIG.
After fixing by attaching, the surface side of the board 1 where the main body 3 of the electrical components 2 is located is coated with moisture-resistant insulation paint or filled with an insulating resin. It has been carried out since. These insulating resins or moisture-resistant insulating paints (hereinafter referred to as the solidifying insulating material 4) are initially liquid and solidify after being applied or filled. In FIG. 5, 5 is a lead of the electrical component 2, 6 is a through hole formed in the substrate 2 and through which the lead 5 is inserted, and 7 is a soldering part.

In conventional circuit board devices of this type, the leads of electrical components are linear or simply L-shaped. For example, the electrical component 2 shown in FIG. 5 is a resistor, or nodes 5 coaxially protrude from both ends of the main body 3, and these nodes 5 are bent vertically at the base on the main body 3 side. From then on, it's a straight line. Further, the board 1 has a structure in which the entire lower part of the main body 3 of the electrical component 2 is closed.

Therefore, the solidifying insulating material 4 applied or filled is necessary to ensure insulation, and even though it is originally only needed on the leads 5 of the electrical component 2, It also gets into the space between the main body 3 of the electrical component 2 and the substrate 1 and solidifies.

By the way, the solidifying insulating material 4 expands or contracts during the solidifying process or as a result of temperature changes.

When the solidifying insulating material 4 between the main body 3 of the electrical component 2 and the substrate 1 expands or contracts, the solidifying insulating material 4 pushes or pulls the main body 3 of the electrical component 2. Displace in each direction. However, with the shape of the conventional adhesive 5, the lead 5 could not cope with the displacement of the main body 3 of the electrical component 2, and cracks 8 were sometimes formed in the adhesive part 7 due to stress. If the soldering part 7 cracks, the reliability of the connection between the electrical components 2 will be impaired.

(Problems to be Solved by the Invention) As mentioned above, in conventional circuit board devices, the solidifying insulating material gets into the space between the main body of the electrical component and the board and hardens. Since the leads of the electrical components could not fully cope with the expansion and contraction of the insulating material, stress was applied to the soldering parts, causing problems such as cracks occurring in the soldering parts.

The present invention is intended to eliminate such problems, and the invention according to claim 1 is directed to eliminating stress due to expansion and contraction of the solidifying insulating material between the main body of the electrical component and the board. The purpose of the present invention is to provide a highly reliable circuit board device that can absorb the damage caused by the leads of electrical components and prevent damage to soldered parts. In contrast, the invention described in claim 2 can prevent the solidifying insulating material from accumulating and solidifying between the main body of the electrical component and the board, and therefore, soldering may cause damage to the part. The purpose of the present invention is to provide a highly reliable circuit board device that does not cause any problems.

[Structure of the invention]

(Means for Solving the Problems) A circuit board device of the present invention includes a circuit board, an electrical component having a lead protruding from a main body portion and having a tip end portion of the lead attached to the board in a half IB, and a circuit board device on the board. In order to achieve the above object, the circuit board device according to claim 1 is provided with a solidifying insulating material made of resin or the like which is applied or filled on the surface where the main body of the electrical component is located. A bent portion is formed in the intermediate portion of the lead of the electrical component, which can be deformed in response to displacement of the electrical component in each direction with respect to the substrate.

In addition, in order to achieve the above object, a circuit board device according to a second aspect of the present invention includes forming a hole in a position below a main body of the electrical component in the board, through which the solidifying insulating material hangs down until it hardens. This is what I did.

(Function) In the circuit board device according to claim 1 of the present invention, after the tips of the leads protruding from the main body of the electrical component are soldered to the board, resin or the like is applied to the surface of the board where the main body of the electrical component is located. Apply or fill with a solidifying insulation material. This solidifying insulating material gradually solidifies (but the solidifying insulating material that has entered between the board and the main body of the electrical component expands and contracts during the solidifying process or with temperature changes, causing the board Even if an electrical component is displaced, the bend formed in the middle of the lead of the electrical component deforms in response to the displacement in each direction, absorbing stress and preventing soldering. The stress applied to the parts is reduced, and this soldering prevents damage to the parts.

Further, in the circuit board device according to claim 2, after the electrical component is similarly attached to the board by soldering, a solidifying insulating material is applied or filled on the surface of the board where the main body of the electrical component is located. At this time, even if the solidifying insulating material gets between the board and the main body of the electrical component, the solidifying insulating material will harden from the hole located below the main body of the electrical component in the board. This prevents the solidifying insulating material from accumulating and solidifying between the board and the main body of the electrical component. Therefore, the pressure caused by the expansion and contraction of the solidifying insulating material will not be applied to the soldered portion of the lead through the main body of the electrical component.

(Example) Examples of the present invention will be described below. First, the configuration of an embodiment of the circuit board device according to claim 1 is shown in FIGS. 1 and 2.
This will be explained based on the diagram.

Reference numeral 11 denotes a printed circuit board, and this board 11 has a back surface (lower surface in FIG. 1) or a soldering surface, and a conductive pattern is formed on the back surface. Further, a large number of through holes 12 are formed through the substrate 11 so as to face the conductive pattern.

A large number of various electrical components 13 such as resistors, capacitor coils, diodes, and transistors are mounted on the printed circuit board 11.
This has a structure in which two or three or more glue sticks 15 protrude from the main body 14 in the shape of legs. The tips of these leads 15 made of elastic metal wires are passed through the through holes 13 of the substrate 11 from the front side to the back side, and soldered to the conductive patterns of the substrate 11. In FIG. 1, 16 indicates the soldering part.

Furthermore, in FIG. 1, 17 is the printed circuit board 11.
It is a solidifying insulating material made of resin that is coated or filled on the surface where the main body 14 of the electrical component 13 is located.

As shown in FIG. 1, each lead 15 of each electrical component 12 to which at least the solidifying insulating material 17 is applied or filled is provided above the substrate 11, that is, in the main body portion 1.
A bent portion 18 is formed in the middle portion located on the 4th side.

This bent part 18 has a shape in which the part of the lead 15 that hangs linearly protrudes horizontally in a substantially V-shape in the middle, and the bent part 18 has a shape in which the part of the lead 15 that hangs in a straight line projects in a substantially V-shape in the horizontal direction. It can be deformed in response to displacement.

Next, the operation of the above embodiment will be explained.

First, the lead I5 of the electrical component 13 is passed through the through hole 12 of the printed circuit board 11 and soldered, and the electrical component 1
Fix 3. Thereafter, on the surface side of the board 11, a moisture-resistant insulating paint made of resin is applied as a solidifying insulating material 17 to the electrical component 13 by spraying or brushing, or the entire body is filled with an insulating resin. Particularly, FIG. 1 shows a case in which resin is filled, and electrical components 13 are encapsulated in this resin.

This solidifying insulating material 17 is initially liquid and gradually solidifies, but also enters between the substrate 11 and the main body 14 of the electrical component 13. Then, the solidifying insulating material 17 that enters between the substrate 11 and the main body 14 of the electrical component 13 and adheres to both expands during the solidifying process or due to temperature changes.
When contracted, the main body portion 14 of the electrical component 13 is displaced with respect to the substrate 11. However, the stress is absorbed by deforming the bent portion 18 formed at the intermediate portion of the lead 15 of the electrical component 13 in response to the displacement of the main body 14 of the electrical component 13 in each direction.

For example, when the main body 14 of the electrical component 13 is displaced in the direction approaching the board 11, the V-shaped bent part 18 is deformed to close, and the main body 14 is displaced in the direction away from the board 11. , the bent portion 18 deforms to open, thereby providing a cushioning effect.

In this way, the stress applied to the soldering portion 16 and the like is reduced, thereby preventing damage to the soldering portion 16 and the like. This improves the reliability of the connection of the electrical components 13 when moisture-proofing and insulation treatment is performed, and further increases the reliability of the lighting device or the like used in the circuit board device.

FIG. 3 shows another embodiment of the circuit board device according to claim 1, in which the middle part of the lead 15 of the electrical component 13 is twisted to form a kink-shaped bent part 19 there. are doing. Even with the bent portion 19 having such a shape, the electrical component 13
can be deformed in response to displacement in each direction with respect to the substrate 11.

Next, an embodiment of the circuit board device according to claim 2 will be described with reference to FIG.

In this embodiment, the substrate 11 includes at least each electrical component 1 to be coated or filled with the solidifying insulating material 17.
A hole 21 is formed below the main body 14 of No. 3. This hole 21 is particularly large in size for the solidifying insulating material 17.
It is enough to let it drip down before it hardens.

After the electrical component 13 is attached to the board 11 by soldering, for example, the electrical component 13 is attached to the front surface side of the board 11.
A moisture-resistant insulating paint made of resin as a solidifying insulating material 17 is applied by spraying or brushing.

At this time, the solidifying insulating material 17 or the board 11 and the electrical component 13
Even if the solidifying insulating material 17 gets between the main body part 14 of
The solidifying insulating material 17 does not accumulate and harden between the substrate 11 and the main body 14 of the electrical component 13. That is, in the end, the solidifying insulating material 17 will be inserted between the board 11 and the main body 14 of the electric component I3 with enough room,
There is a gap 22 between the board 11 and the main body 14 of the electric component j3.
Therefore, even if the solidifying insulating material 17 expands or contracts,
The main body 14 of the electrical component 13 is not pushed or pulled strongly. Therefore, the pressure caused by the expansion and contraction of the solidifying insulating material 17 will not be applied to the fastener 16 of the lead 15 through the main body 14 of the electrical component 13, and this soldering will cause damage to the part 16. There's nothing to do.

In this way, the reliability of soldering can be stably improved.

Of course, the lead 15 of the electrical component 13 is made of solidifying insulating material 1.
7, the leads 1 of the plurality of electrical components 13
The insulation between 5 and 5 is not impaired.

Note that the position where the hole 21 is formed in the substrate 11 is not limited to the position directly below the main body part 14 of the electrical component 13, but may be around the position directly below the main body part 14. In addition, the hole 21
The shape may be rounded corners. Furthermore, the number of holes 21 formed below the main body 14 of one electrical component 13 is also
The number is not limited to one, but may be two or more.

〔Effect of the invention〕

According to the present invention, in a circuit board device in which leads of electrical components are soldered to a board and a solidifying insulating material is applied or filled on the surface of the board where the main body of the electrical component is located, the following effects can be obtained. It will be done.

In the circuit board device according to claim 1, the bending portion that can be deformed in response to the displacement of the electrical component in each direction with respect to the board is formed in the intermediate portion of the lead of the electrical component, so that the main body of the board and the electrical component Even if the hardening insulating material that has entered the opening expands or contracts, the stress is absorbed by the bent part of the lead, and the stress applied to the soldering part is reduced. damage can be prevented and reliability is improved.

In the circuit board device according to the second aspect of the present invention, a hole is formed at a position below the main body of the electrical component on the board to allow the solidifying insulating material to hang down until it hardens, so that when applying or filling the solidifying insulating material, By flowing the solidifying insulating material into the hole, it is possible to prevent the solidifying insulating material from accumulating and solidifying between the main body of the electrical component and the board, thereby reducing the pressure caused by the expansion and contraction of the solidifying insulating material. However, the soldering does not extend to the parts through the main body part, and this soldering does not cause damage to the parts, improving reliability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the circuit board device according to claim 1 of the present invention, FIG. 2 is a plan view of the same, and FIG. 3 is a sectional view showing another embodiment of the circuit board device according to claim 1. FIG. 4 is a sectional view showing an embodiment of the circuit board device according to claim 2 of the present invention,
FIG. 5 is a sectional view showing an example of a conventional circuit board device. DESCRIPTION OF SYMBOLS 11... Board, 13... Electrical component, 14... Main body of electrical component, 15... Lead of electrical component, 17... Solidifying insulating material, 18... Bent part, 19... Bent part, 2... Hole.

Claims (2)

[Claims] (1) a board; an electrical component having a lead protruding from a main body; the tip of the lead is soldered to the board;
a solidifying insulating material coated or filled on the surface of the board where the main body of the electrical component is located; A circuit board device characterized in that a bent portion is formed to be deformable. (2) a circuit board; an electrical component having a lead protruding from a main body, the tip of the lead being soldered to the circuit board;
a solidifying insulating material coated or filled on a surface of the board where the main body of the electrical component is located, and applying the solidifying insulating material to a position below the main body of the electrical component on the board until it hardens. A circuit board device characterized in that a hole for hanging is formed as an opening.