JPH06334324A - Reflow method for discrete component - Google Patents

Abstract

PURPOSE:To simplify a process at the time of soldering a discrete component by reflowing, by previously printing cream solder on the land of a hole into which a component is inserted, and performing reflow after the component is inserted. CONSTITUTION:Cream solder is printed on all lands formed on the rear of a printed board (101). The mounting region of a surface mount component is coated with adhesive agent which cures at a normal temperature (102). A surface mount component is mounted (103). The printed board is inverted (104). Ceam solder is printed on the land of the surface for the mount component (105). A surface mount component is mounted (106). A discrete component is inserted (107). Reflow is performed (108). When the lead is bent by automatically inserting the discrete component, the process (104) for inverting the printed board is increased after the discrete component is automatically inserted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inserting and soldering discrete components on a printed wiring board.

[0002]

2. Description of the Related Art Insertion and soldering of a discrete component of a conventional double-sided printed wiring board are described in FIGS.
As shown in (4), the mounted components were inserted after they were mounted and soldered in a solder bath.

[0003]

SUMMARY OF THE INVENTION In this conventional method,
Depending on the surface-mounted component, when passing through the solder bath, there are components that require drying before mounting as shown in FIG. 5, and drying equipment and processes are required. Alternatively, in the design of the printed wiring board, there is a design restriction such that the surface mount component is arranged only on the reflow surface.

Therefore, an object of the present invention is to solder discrete components by reflow to simplify the process,
And to reduce design constraints.

[0005]

In order to solve the above-mentioned problems, the present invention provides a method for reflowing discrete components in which discrete components are mounted on a printed wiring board. This is a method for reflowing discrete components in which solder is printed and discrete components are inserted, and then reflow is performed to perform soldering.When the discrete components are automatically inserted, the land of the insertion hole is automatically inserted after the discrete components are automatically inserted. The present invention provides a reflow method for discrete components, in which cream solder is applied to, and reflow is performed to perform soldering.

[0006]

Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a process drawing of component mounting and soldering according to the present invention.

FIG. 2 shows a printed state of cream solder,
FIG. 3 shows a state when the discrete component is inserted.

In the method according to the present invention, as shown in FIG. 1, cream solder is printed on all lands on the back surface of the printed circuit board (101). In this case, the land of the discrete component is printed on the entire land as shown in FIG.

Next, an adhesive which cures at room temperature is applied to the surface mounting component mounting portion (102), the surface mounting component is mounted (103), and the back surface process is completed.

Next, the printed circuit board is turned over (104),
Print the solder paste on the land of the mounted parts on the surface (10
5) After mounting the surface mount component (106), insert the discrete component (107) and perform reflow (10).
8).

In addition, when the leads are bent by automatic insertion of the discrete component, as shown in FIG. 4, after the discrete component is automatically inserted, the printed board is turned over (1
04) The number of steps is increased, cream solder is applied in the same manner as the adhesive application (111), the printed circuit board is inverted (104), and after mounting the surface mount component (106), reflow is performed (108). .

[0013]

As described above, according to the present invention, in a discrete component reflow method for mounting a discrete component on a printed wiring board, cream solder is printed in advance on the land of the hole into which the discrete component is inserted, and the discrete component is printed. This is a reflow method for discrete parts that performs reflow and soldering after inserting parts.When automatically inserting discrete parts, after applying the discrete parts, apply cream solder to the land of the insertion hole and then reflow. By performing the soldering, the soldering is performed only once, so that the process is simplified.

Further, since the solder bath is not used, it is not necessary to dry the parts, the damage to the parts is reduced, and the reliability of the parts is improved.

Further, it has an excellent effect such that restrictions on the design of the printed circuit board can be reduced.

[Brief description of drawings]

FIG. 1 is a process drawing of component mounting and soldering of a printed wiring board of the present invention.

FIG. 2 is a sectional view of a printed state of the cream solder of the present invention.

FIG. 3 is a sectional view of a state in which the component of the present invention is inserted.

FIG. 4 is a mounting and soldering process diagram when the leads of the discrete component of the present invention are bent.

FIG. 5 is a process diagram of component mounting and soldering in the case of conventional single-sided reflow.

FIG. 6 is a process diagram of component mounting and soldering in the case of conventional double-sided reflow.

[Explanation of symbols]

 20 Printed Circuit Board Section 21 Land Section for Discrete Parts 22 Cream Solder Section 23 Terminal for Discrete Parts

Claims (2)

[Claims] 1. A discrete component reflow method for mounting a discrete component on a printed wiring board, wherein cream solder is printed in advance on a land of a hole for inserting the discrete component, the discrete component is inserted, and then reflow is performed. Reflow method for discrete parts to be soldered. 2. In the reflow method for discrete components, when the discrete components are automatically inserted,
2. The method for reflowing discrete components according to claim 1, wherein after the discrete components are automatically inserted, cream solder is applied to the lands of the insertion holes and reflowing is performed for soldering.