JPH05160541A - Printed board - Google Patents

Abstract

PURPOSE:To easily mount electronic parts like very small chip parts on a printed board, in the case of the surface installation. CONSTITUTION:On a printed board 1, a recessed part 1a is dug in the shape of an electronic parts 2 to be mounted, and said parts 2 is mounted so as to be buried. Highly precise positioning is not necessary because the electronic parts 2 may be buried in the recessed part 1a. Terminals 2b of the electronic parts 2 are connected with printed wirings as follows. For example, as shown in the figure, solder-flow holes 1f penetrating to the rear are formed, and solder is made to flow into the holes from the rear, thereby connecting the terminals 2b with printed wirings 5a, 5c, etc. On the other hand, the printed wiring on the board surface is formed as far as the edge of the recessed part 1a, and the terminals of the electronic parts are connected with the printed wiring by using solder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board on which electronic parts such as chip parts are mounted.

[0002]

2. Description of the Related Art In the surface mounting of a printed circuit board, which has been widely used in recent years, it is not necessary to insert a lead wire into a lead wire insertion port and pass the lead wire through the insertion mounting.
This has the advantage that the work of mounting the printed circuit board becomes easier.

In surface mounting, electronic components such as chip components are conventionally positioned and mounted with their terminals accurately placed on printed wiring provided on a printed circuit board. ..

In order to reduce the size and weight of the printed circuit board, ultra-miniaturized chips and the like are mounted on the printed circuit board.

[0005]

However, since the above-mentioned miniaturized electronic parts have a small pitch between terminals, these electronic parts are placed on the printed wiring of the printed circuit board. In order to accurately position and mount, an automatic mounting machine that performs highly accurate positioning and mounting work must be used.

Therefore, in order to provide a highly accurate automatic mounting machine, a large amount of capital investment is required, which causes a problem that the manufacturing cost of the printed circuit board becomes high.

Therefore, an object of the present invention is to make it possible to easily mount an ultra-miniaturized electronic component or the like,
To provide a printed circuit board.

[0008]

In order to achieve the above object, the printed circuit board of the present invention is provided with a recessed portion engraved in the shape of the electronic component to be mounted at the position where the electronic component is mounted.

[0009]

The electronic component is mounted so as to be embedded in the recess on the printed circuit board, whereby it is possible to easily confirm whether or not the electronic component is positioned by checking whether the electronic component has entered the recess. The complexity of positioning work can be eliminated.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

This embodiment relates to a case where an electronic component is connected to a jumper wire.

In FIG. 1, a recessed portion (hole) 1a engraved in the shape of the chip component 2 is provided on the surface of the printed circuit board 1 at the mounting position of the chip component 2. The flat cross-sectional shape of the recess 1a is substantially the same as the cross-sectional shape of the chip component 2 except for the solder rising groove 1d described later, and is slightly larger so that the chip component 2 can be inserted. The depth of the depression 1a is such that the bottom surface 1b of the depression 1a and the back surface 1c of the printed circuit board 1 are arranged so that solder can flow into the depression 1a through a solder inflow hole 1f described later.
Is determined based on the fact that the thickness between and is determined.

Next, facing the terminal portion of the chip component 2,
A semi-circular solder rising groove 1d is formed in the center of both sides of the recess 1a in the thickness direction of the printed circuit board 1. Printing is performed from the bottom surface 1b of the recess 1a continuously to the groove 1d. On the back surface 1c of the substrate 1, at the same center as the groove 1d,
Solder inflow hole (through hole) 1f with the same diameter and circular cross section
Has penetrated. The solder inflow hole 1f and the solder rising groove portion 1d are plated with Cu or the like in order to facilitate the inflow of solder.

Next, groove portions 1g for embedding the jumper wires are formed on both outer sides of the recessed portion 1a so as to face the terminal portions of the chip component 2. Further, a jumper wire 3 is provided at both ends of the bottom surface 1h of the groove portion 1g and a back surface 1 of the printed circuit board 1 is provided.
A hole 1i for penetrating c is formed.

Next, the back surface 1c of the printed circuit board 1 is provided with printed wiring. That is, the solder inflow hole 1f
And around the jumper wire hole 1i,
Ring-shaped conductive films 5a and 5 such as Cu foil and Cu plating
b is formed, and C is provided between the ring-shaped conductive films 5a and 5b of the opposing solder inflow hole 1f and jumper wire hole 1i.
A linear conductive film 5c such as u foil or Cu plating is formed (see FIG. 2A). The other jumper wire hole 1i
On the ring-shaped conductive film 5b formed on the periphery of, a linear conductive film 5d reaching another position on the back surface 1c of the printed board 1 is formed.

Next, the chip component 2 is in the shape of a rectangular chip, and the L-shaped terminal electrodes 2 are formed on the lower end portions of the opposite side surfaces 2a and the bottom face portion of the chip component continuous with the opposite side faces 2a.
b is formed. As the chip component 2, various electronic components such as resistors, capacitors and inductors are applied.

The jumper wire 3 is bent in a U shape, and the portion 3a penetrating the jumper wire hole 1i is
The surface coating has been removed.

Next, the operation will be described with reference to FIG.

The chip component 2 is embedded in the recess 1a of FIG. 2 (a). At this time, the chip component 2 need only be fitted into the recessed portion 1a, so that complicated positioning confirmation work is not required.
That is, when performing the manual work, while holding the chip component with tweezers or the like, the bottom surface of the chip component should be
When it is confirmed that the chip component has entered the recess 1a by sliding on the upper surface of the printed circuit board 1 in the vicinity of, it means that the positioning is performed.
Mounting is completed by lowering and embedding the chip component 2. Therefore, the mounting work can be easily performed. Even when the automatic mounting machine is used, the chip component is similarly transported to the recess 1a and inserted so as to be fitted into the recess 1a. The chip member 2 and the bottom surface 1 of the recess
An adhesive or the like is used to bond between b and the like. When the chip component 2 is mounted in the recess 1a, the terminal electrode 2b faces the solder inflow hole 1f (FIG. 2 (b)).

Next, the jumper wire 3 is inserted into the groove 1g of the jumper wire, and both ends 3a thereof are inserted into the jumper wire insertion hole 1.
i is penetrated (FIG. 2B).

Then, a solder dip treatment is applied to the back surface 1c of the printed circuit board. As a result, the solder 6 adheres to the ring-shaped conductive film 5a around the solder inflow hole 1f,
In addition, the solder inflow hole 1f is lifted to the terminal electrode 2 of the chip.
b, and, if necessary, through the semicircular groove 1d to reach near the upper surface of the printed board 1. As a result, the terminal electrode 2b of the chip component 2 and the ring-shaped conductive film 5a are connected (FIG. 2C). At the same time, since both ends 3a of each jumper wire are connected to each ring-shaped conductive film 5b by the solder 7,
Both terminal electrodes 2b of the chip 2 are connected to a predetermined other element or the like via the jumper wire 3 (FIG. 2 (c)).

The present invention makes it possible to mount chip parts whose mount positioning is difficult as described above without using an automatic mounting machine, and in the future, a wide variety of parts such as ultra-small chip electronic parts of rice grain size will appear. However, it is possible to easily mount these components.

In the above embodiment, the terminal electrode 2b of the chip is connected to another element or the like through the jumper wire 3 by the printed wiring. However, the terminal electrode 2 is not connected through the jumper wire but is connected by the printed wiring to the other element or the like. Of course, the present invention also applies to the case of connecting with. Further, although the above-mentioned embodiment is a square chip, in the case of a round chip or a modified chip,
The present invention is of course applicable.

In the above embodiment, the side surface of the recess 1a,
Alternatively, the side surface 2a of the chip component or both of them may be provided with a tapered portion. This allows
It is possible to more easily fit the chip component 2 into the recess 1a.

Further, in the above embodiment, the solder rising groove 1d of the depression 1a does not necessarily have to be provided. In this case, the distance between the side surfaces of the recessed portion 1a where the solder inflow holes 1f are provided is made larger than the distance between the side surfaces 2a where the terminal electrodes of the chip component 2 are provided, and the recessed portion of the chip component 2 is formed. At the time of mounting on the chip 1a, the side surface 2a on which the terminal electrode of the chip component 2 is provided and the solder inflow hole 1f of the recess 1a
A gap may be provided between the side surface and the side surface where the solder is provided, and the solder may flow into the gap.

Further, in the above embodiment, the solder inflow hole 1
Although f is provided and connected to the printed wiring on the back surface 1c of the printed circuit board through the solder in the hole 1f, it may be connected to the printed wiring on the front surface of the printed circuit board. That is, for example, the terminal electrode is provided at the entire height of the side surface of the chip component, and the printed wiring on the surface of the printed board is extended to the edge of the recess 1a where the terminal electrode of the chip component is located. Alternatively, the terminal electrodes may be connected to the printed wiring on the surface of the printed circuit board by a solder dipping process, a reflow process, or the like. In this case, the depth of the recess may be shallow.

In the surface mounting, the present invention is mixed with conventional chips or the like which are mounted on a plane without providing a recessed portion,
May be applied. In this case, for example, on the surface of the printed circuit board, a recessed portion is provided at the position where the ultra-small chip component is mounted, and this chip component is mounted in the recessed portion,
The chip component may be mounted on a plane without providing a recess at the position where the chip component of a normal size is mounted.

The present invention can also be applied to mixed mounting with insertion mounting. In this case, when the terminals of the chip component 2 are connected to the printed wiring on the back surface of the printed circuit board by the solder inflow holes 1f as in the above embodiment, the chip component 2 is collectively soldered by dipping or the like. The connection of the terminal to the printed wiring on the back surface of the printed circuit board and the connection of the lead wire of the insertion mounting component to the printed wiring on the back surface of the printed circuit board can be performed at the same time.

[0029]

According to the present invention, the printed circuit board is provided with the recessed portion and the electronic component is mounted by fitting the electronic component into the recessed portion. Therefore, high-level positioning is unnecessary, and therefore, high-level positioning work is performed, which is expensive. Therefore, it is possible to reduce the manufacturing cost of the printed circuit board without requiring any equipment such as an automatic mounting machine.

[Brief description of drawings]

FIG. 1 is a perspective view showing an electronic component and a printed circuit board on which a concave portion engraved in the shape of the electronic component is formed.

2A and 2B are cross-sectional views taken along a direction connecting both solder inflow holes 1f in FIG. 1, where FIG. 2A is a view before an electronic component is mounted and FIG. 2B is a state in which the electronic component is mounted. Figure, Figure (c)
[Fig. 3] is a diagram showing a state where soldering has been performed.

[Explanation of symbols]

 1 Printed circuit board 1a Dimple 2 Electronic component

Claims (1)

[Claims] 1. A printed circuit board, wherein a recessed portion engraved in the shape of the electronic component to be mounted is provided at a position where the electronic component is mounted.