KR200157790Y1 - Parts installation system of pcb using lithograph display module - Google Patents

Abstract

In a component mounting structure of a printed circuit board for a flat panel display module for welding a SMD component having a plurality of terminals to a printed circuit board for controlling an image by controlling the flat panel display, the connection terminal is formed by melting and flowing down solder. In order to prevent a short between the pads, the intermediate pad 20a of the printed circuit board is formed longer than the side pad 20b, and the solder formed on the side pad flows by forming solder on the outside where the mounting SMD component is placed. Even when it is lowered, a short does not occur and the defect rate of the product can be reduced.

Description

Component mounting structure of printed circuit board for flat panel display module

1 is a plan view showing a component mounting structure of a printed circuit board according to the present invention.

Figure 2 is a side view showing a component mounting structure of a printed circuit board according to the present invention.

3 is a plan view showing a component mounting structure of a printed circuit board according to the prior art.

4 is a side view showing a component mounting structure of a printed circuit board according to the prior art.

* Explanation of symbols for main parts of the drawings

1: printed circuit board 20: pad part

20a, 20b: Pad 3: Solder

4: SMD 3 Pad Parts

[Industrial use]

The present invention relates to a component mounting structure of a printed circuit board (hereinafter, abbreviated as PCB) for a flat panel display module, and more specifically, a SMD (Surface Mounting Device) 3 pad component on a flat panel display, particularly a PCB for driving a fluorescent display tube. The present invention relates to a component mounting structure of a PCB which can reduce product defects while preventing a short due to melting of a solder.

[Prior art]

As is well known, VFD (Vacuum Fluorescent Display) is a type of flat panel display, in which at least one surface is exposed to a phosphor coated on the anode by accelerating hot electrons emitted from a direct-type cathode called a filament in a transparent vacuum vessel by direct current or pulse voltage. A self-luminous display tube which collides and emits light and displays information such as a desired pattern, that is, a character or an image, usually has a structure of a triode formed of a grid for controlling electrons.

In general, such a VFD forms an outer container to maintain a vacuum by integrally combining the front glass substrate, the rear insulator substrate, and the side glass as a frit made of low melting glass to form an image.

A filament that emits hot electrons, that is, a cathode, a lattice grid for controlling the hot electrons, an anode wiring having a predetermined pattern, an anode conductive layer and a phosphor stacked on the anode wiring, and insulating The layer is composed.

Here, the connection pattern for applying a voltage is grounded at the cathode, grid, and anode, which is connected to a lead pin drawn out of the outer container.

In addition, a predetermined driving circuit is required to turn on the VFD having the above-described configuration in a predetermined pattern. The PCB is disposed under the rear insulator substrate of the VFD, and is grounded to the lead pin to provide a predetermined signal. To control the VFD.

Here, the PCB is a component such as a resistor, a capacitor, a coil, a transistor, an integrated circuit and a switch on a printed wiring board on which a predetermined wiring pattern is formed, and is configured to serve as a predetermined driving circuit.

A structure for mounting a known SMD 3 pad component on such a PCB is shown in FIG.

As can be seen from the drawing, a solder 3 is applied to a pad portion (see Fig. 4) serving as a terminal of a PCB on which a predetermined wiring pattern (not shown) is formed.

The solder 3 is formed by a normal printing process made through a mask. A normal SMD 3 pad component 4 is placed on the upper side of the solder 3 and fused.

4 is a cross-sectional view showing a coupling structure of the above-described PCB and SMD 3 pad components, and 2 denotes a pad portion serving as a connection terminal of the PCB 1 and the component.

Solder 3 is printed on the pad 2, and an SMD 3 pad component 4 is disposed above it. At this time, the pad part 2 and the SMD 3 pad part 4 are fused through separate heating means (not shown).

[Problem trying to solve]

The problem associated with the above-described combination structure of the PCB and the SMD 3 pad component of the prior art is that a short occurs during the fusion process.

For example, the solder printed on the pad portion of the PCB is formed in a semicircular shape by a predetermined adhesive force with the pad portion.

The solder 3 is placed on the upper side of the solder to perform a fusion process. At this time, the solder is pushed out of the pad portion by the heat and the weight of the component, that is, as shown by the dotted line 3a of FIG. A short occurs between the pads.

The short between these parts leads to a defective product of the PCB, which is accompanied by a decrease in productivity and a waste of production cost.

In view of the above problems of the prior art, an object of the present invention is to improve the pad structure of the PCB while fusing SMD 3 pad components on a PCB that is a flat panel display driving circuit so as to prevent a short between pad portions. It is to provide a pad structure of a PCB.

[Means to solve the problem]

In order to achieve the above object, the present invention proposes a component mounting structure of a PCB having the following configuration.

That is, the present invention is to form a pad portion that is a connection terminal on the PCB, the inner pad out of the unspecified plurality of pad arrangement is formed longer than the pads arranged on both sides; When solder is printed on the inner pad, the side of the mounting component is formed to be in contact with the outside.

Here, the mounting component is made of a SMD 3 pad component.

[Action]

The component mounting structure of the PCB of the present invention having the above-described configuration has a pad portion formed on the PCB, both sides of which are shortened, and a pad formed in the middle of the pad is long, and the outside of the center pad has SMD 3 pad components on the outside except the middle. By printing the solder and mounting the component, this can substantially eliminate the occurrence of short between pads, which has been a problem in the past.

That is, according to the present invention, the three pads formed on the PCB have only a middle pad formed long, and the pad is divided into approximately three parts, and the two pads are disposed on both sides except the middle part where the corresponding pad of the SMD 3 pad component is placed. Solder is formed.

In this case, when the SMD 3 pad component is placed on the pad portion of the PCB and the fusion process is performed, the solder on both sides is pushed and melted by the heat and the weight of the component, while the solder on the middle portion is melted by the capillary action. While contacting the sides of the SMD 3 pad component from both sides of the pad.

Therefore, according to the present invention, even if the molten solder flows between the pads on both sides of the PCB and the SMD 3 pad component, a short does not occur.

EXAMPLE

Hereinafter, a preferred embodiment for realizing the present invention will be described with reference to the accompanying drawings.

1 is a plan view showing a component mounting structure of a PCB according to the present invention, 1 is a PCB for controlling a flat panel display.

On the PCB 1, a pad portion 20 serving as a ground terminal is formed, and on top thereof, a solder 3 is formed for electrical connection with the mounting component.

Here, the pad unit 20 is composed of three pads, which are pads 20b on both sides formed in the same manner as in the related art, and intermediate pads 20a formed larger than the length of the side pads 20b. Consists of.

The intermediate pad 20a has a relationship of 1.5L ≦ L1 with respect to the length L of the side pad 20b, which is to secure a space of the solder 3 formed on the intermediate pad 20a. When 1.5L≥L1, the application amount of the said solder 3 is small, and a bad contact arises.

On the other hand, the solder 3 is printed on the feather section 20 via a mask, and a normal SMD 3 pad component 4 is disposed above the solder 3.

In this case, the solder 3 is formed on the intermediate pad 20a, which is a position where the SMD 3 pad component 4 is in contact with the side surface of the component (up and down in the drawing). Is formed.

The printing method of the solder 3 is to prevent the short between the pads in the related art. When the solder 3 is melted by a heating means (not shown), the solder formed on the intermediate pad 20a is subjected to the capillary phenomenon. By the adhesive force, the solder 3 is connected to the side of the SMD pad 3, and the solder formed on the side pad 20b is pushed to the side as in the prior art and fusion is performed.

The coupling structure between the pad portion 20 and the SMD 3 pad component 4 of the PCB 1 will be described in more detail with reference to FIG. 2.

FIG. 2 is a side view of the above-described FIG. 1 and shows a component mounting structure of a PCB according to the present invention.

As shown, the solder 3 is printed on the pad portion 20, and the SMD 3 pad component 4 is disposed on the pad portion 20.

Meanwhile, the SMD component is not limited to the three pad structure, and includes three or more pad structures, and reference numeral 4a in the drawing denotes a pad of the SMD component.

At this time, the pad part 20 and the SMD 3 pad part 4 are fused through separate heating means (not shown), and the solder 3 is melted by heat and load of the part, Pushed outward.

This solder 3 is shown as dashed lines 3a and 3b in the figure, and the solder 3 formed on the side is fused and pushed to the side as dashed line 3a, and the solder formed on the intermediate pad 20a. (3) is fusion | melted like the dotted line 3b by the adhesive force of SMD3 pad components.

Therefore, the fusion structure of the pad portion 20 and the SMD 3 pad component 4 of the PCB 1 according to the present invention does not generate a short between the pads, unlike in the prior art, which can effectively eliminate the defect factor of the product. will be.

[Effect of design]

As described above, the component mounting structure of the PCB for a flat panel display module according to the present invention is formed such that the intermediate pad is longer than the side pad in order to prevent a short with the intermediate pad due to the melting phenomenon of the solder formed on the side pad. By forming a solder on the outside where the mounting component is placed, a short does not occur even when the solder formed on the side pad melts.

Therefore, according to the present invention, it is possible to achieve the effect of improving the productivity and reducing the production cost by substantially eliminating defects in the manufacturing process of the PCB.

In addition, the present invention is not limited to the above-described embodiment, and is applicable to a component mounting structure of a PCB used as a driving circuit of all electronic products.

Claims (2)

In the component mounting structure of a printed circuit board for a flat panel display module for welding a SMD component having a plurality of terminals to a printed circuit board for controlling an image by controlling the flat panel display, an intermediate pad 20a formed on the printed circuit board ) Is formed longer than both side pads (20b), and in the case of printing the solder (3) on the intermediate pad (20a), it is formed to contact the outside of the SMD component (4) Component mounting structure of printed circuit board for module. The structure of claim 1, wherein the length of the intermediate pad (20a) is at least 1.5 times the length of the side pad (20b).