JPH04367300A - Thermal caulking device for electronic component - Google Patents

Abstract

PURPOSE:To install electronic components on a circuit board in a stable form and moreover, to make possible a caulked molding, which can stand even reheating, even in the case the molding parts to be caulked of the electronic components consist of a material having delicate thermal properties. CONSTITUTION:A spare heating mechanism 2 is provided directly before a caulking mechanism 3, molding parts 103 to be caulked of electronic components 100a and 100b temporarily installed on a circuit board 101 are preheated and after that, these molding parts 103 are pressed by caulking chips 19a and 19b while being heated by the chips 19a and 19b, whereby the components 100a and 100b are permanently installed on the board 101 by performing a thermal caulking to the board 101.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal crimping device for fixing electronic components to a printed circuit board (hereinafter simply referred to as a circuit board).

0002

2. Description of the Related Art Today, there is a tendency for the work of mounting electronic components on a circuit board to be automated, from the process of mounting the electronic components onto the circuit board to the soldering process. Therefore, each process requires a work method suitable for automation. FIG. 5 is a side view schematically showing the structure of a conventional thermal crimping device used in a process of thermally crimping electronic components to a circuit board, which is a process of mounting electronic components on a circuit board. An electronic component 100 serving as a workpiece is transported to the thermal crimping device 50 in a state where it is temporarily attached to a circuit board 101, and this is automatically set. That is, the electronic component 100 includes a component body 100a, a plurality of (in this example, two) terminal pins 102 that protrude from the side surface of the component body 100a and whose tips are bent downward, and the component body 100a. It is integrally constituted by a heat-meltable caulking forming part 103 protruding from the lower surface, and the caulking forming part 103
and the circuit board 101 corresponding to the terminal pins 102, respectively.
By inserting the part to be caulked 103 and the terminal pin 102 from the mounting surface 101a side into a through hole (not shown) drilled in the hole, a part of the part to be caulked 103 and the terminal pin 102 They are set in the thermal crimping device 50 in a temporarily attached state with each protruding toward the solder surface 101b.

On the other hand, the thermal crimping device 50 has a positioning jig 51 and a reference pin 52 disposed on the lower side across the path through which the circuit board 101 is conveyed, and a cylinder 53 and a universal joint on the upper side. 54, a caulking head 55, a caulking tip 56, and the like are arranged. Then, the circuit board 101 on which the electronic component 100 is temporarily attached is transported to the thermal crimping device 50 with the circuit board 101 upside down in advance so that the mounting surface 101a faces downward as shown in the figure, and is placed on the positioning jig 51. 100 electronic parts
By fitting the reference pin 52 into a reference hole (not shown) drilled in the circuit board 101 in which the electronic component 100 and the circuit board 1 are mounted, the electronic component 100 and the circuit board 1
01 positioning is performed.

[0004] When the circuit board 101 on which the electronic component 100 is temporarily attached is set in the thermal crimping device 50 in this manner, the heated crimping chip 56 is lowered together with the crimping head 55 by the drive of the cylinder 53. . Then, the crimping chip 56 comes into contact with a part of the part 103 to be crimped that protrudes from the solder surface 101b of the circuit board 101. Due to this contact, a part of the part 103 to be crimped is heated and melted, and crimping is performed by the pressing force caused by the crimping chip 56 further descending, and the electronic component 100 is permanently attached to the circuit board 101 by this thermal crimping. be done.

[0005] When this thermal crimping process is completed, the circuit board 101 on which the electronic component 100 is permanently attached is taken out from the thermal crimping device 50 by means not shown and transported to the next soldering process. In the soldering process, the electronic component 100 is immersed in the solder surface 101b in a solder dip bath.
The terminal pins 102 of the circuit board 100 are soldered to the printed wiring pattern of the circuit board 100, thereby completing the mounting work.

[0006]

[Problems to be Solved by the Invention] In the conventional heat staking device 50 described above, when the part 103 to be crimped of the electronic component 100 that has been transported in an environment at room temperature is thermally swaged by the swaging chip 56, the forming process is difficult. Figure 6 (
As is clear from A) to (D), the part to be caulked 10
3 starts from the contact surface with the caulking tip 56 and gradually ends, so that the part 1 to be caulked
If 03 is made of a material with delicate thermal properties (for example, PBT), the temperature of the crimping tip 56 must be adjusted to prevent variations in the connector spacing d and crimping diameter φ after molding and to stabilize the shape. Must be managed accurately. ■After molding, reheat (for example, 238°C during soldering dip)
℃ for 1 second), the shape is deformed. ■
It takes time to form the boss. There were some problems.

[0007]The present invention therefore provides a heat-resistant electronic component that can be crimped to a stable shape and withstand reheating even when the part to be crimped is made of a material with delicate thermal properties. The purpose of the present invention is to provide a crimping device.

[0008]

[Means for Solving the Problems] In order to achieve the above object, a thermal crimping device according to the present invention includes a preheating mechanism for preheating a portion to be crimped of an electronic component inserted into a through hole of a circuit board; The structure includes a crimping mechanism that heats and presses the part to be crimped heated by the preheating mechanism with a heated crimping chip member, thereby thermally crimping it against the circuit board.

[0009]

[Operation] In the thermal crimping device according to the present invention, before performing the thermal crimping process, the portion to be crimped of the electronic component temporarily attached to the circuit board is preheated. By performing the preheating treatment, the deformation of the part to be crimped during crimping starts not from the contact surface with the crimping chip but from the middle thereof, so that the part is crimped into a drum shape. This increases the thickness of the molded shape and makes it resistant to reheating at high temperatures. In addition, preheating increases the amount of heat given to the part to be caulked and the molded shape becomes drum-shaped.
Both the connector spacing d and the caulking diameter φ are stabilized.

0010

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic side view showing an embodiment of a thermal crimping device for electronic components according to the present invention. In the figure,
Thermal caulking device 1 according to the present invention includes a preheating mechanism 2 that preheats a portion 103 to be caulked of a pair of electronic components 100a and 100b inserted into a through hole of a circuit board 101.
and the part 1 to be crimped heated by the preheating mechanism 2.
03 to the circuit board 101 by heat.

The preheating mechanism 2 includes a component holding plate 4.
and a substrate holding plate 5 are provided. These plates 4 and 5 are driven by cylinders 6 and 7 to connect electronic components 100a and 100b and circuit board 101.
It plays a role in keeping things in close contact with each other. In addition, a pair of electronic components 10
A pair of blowers 8a, 8b are provided corresponding to 0a, 100b, and heating nozzles 9a, 9b are provided in these blowers 8a, 8b to locally heat the caulking forming portion 103 of the electronic component 100a, 100b. installed. The preheating mechanism 2 having the above configuration is arranged between a pair of conveyor belts 10a and 10b arranged in parallel,
The circuit board 101 conveyed by the conveyor belts 10a and 10b is positioned by a stopper 11. The stopper 11 is driven by a cylinder 12 so as to move in and out of the workpiece conveyance path as appropriate.

Next, the operation of the preheating mechanism 2 will be explained with reference to FIG. 2. First, the stopper 11 is made to protrude onto the conveyance path of the workpiece, and the circuit board 101, which has been conveyed with the electronic components 100a and 100b temporarily attached thereto, is positioned by this stopper 11 (FIG. (A)). . Subsequently, by driving the cylinders 6 and 7, the component holding plate 4 and the board holding plate 5 are lowered and raised, respectively, and the electronic component 10, which is a workpiece, is lowered and raised.
0a, 100b and the circuit board 101 are pressed and brought into close contact (Figure (B)).

In this close contact state, the blowers 8a, 8
Blowing hot air from b. This hot air is sent to the local heating nozzle 9.
a, 9b, and preheats the caulking forming portions 103 of the electronic components 100a, 100b for a set time. After this preheating is completed, the cylinders 6 and 7 are driven to raise and lower the component holding plate 4 and the substrate holding plate 5, respectively (FIG. (C)). Thereafter, the stopper 11 is moved back from the workpiece transport path, and the workpiece is moved to the crimping mechanism 3 by conveyance by the conveyor belts 10a, 10b.

FIG. 3 is a schematic perspective view of the crimping mechanism 3 of FIG. 1. In this caulking mechanism 3, component parts are separately arranged at upper and lower positions of the conveyor belts 10a and 10b, with the workpiece conveyance path formed by the conveyor belts 10a and 10b interposed therebetween. That is, a movable plate 14 holding component holding plates 13a and 13b is provided above the conveyance path so as to be movable up and down, and this movable plate 14 is driven and controlled by a cylinder 15. On the other hand, there is a cylinder 23a on the lower side of the workpiece conveyance path.
, 23b (see FIG. 1) as a driving source.
is provided to be movable up and down, and this movable plate 16
On the top, substrate holding plates 17a, 17b, caulking heads 18a, 18b, caulking chips 19a, 19b, etc. are arranged.

Further, the board holding plates 17a, 17b are slidably supported by rods 20a, 20b, and are urged upward by springs 21a, 21b, and are normally placed above the caulking chips 19a, 19b. The springs 21a, 2
When it receives a force from above that overcomes the urging force of 1b, it is displaced downward. Board holding plate 17a,
When 17b is displaced downward, the caulking tip 19a
, 19b pass through through holes 22a, 22b drilled in the substrate holding plates 17a, 17b.
It protrudes upward from the upper surface of 17b.

Next, the crimping operation of the crimping mechanism 3 will be explained. First, the electronic components 100a, 100b and the circuit board 101 that have been preheated in the preheating mechanism 2 are conveyed by the conveyor belts 10a, 10b, and are moved to the stopper 2 whose drive source is the cylinder 25.
When the electronic components 100a and 100b are positioned by coming into contact with the electronic components 100a and 100b, the component holding plates 13a and 13b lower together with the movable plate 14 to press the electronic components 100a and 100b downward. Next, the lower movable plate 16 rises, and the board holding plates 17a and 17b come into contact with the lower surface (soldering surface) of the circuit board 101, so that the component holding plate 13a
, 13b and the board holding plates 17a, 17b sandwich and position the electronic components 100a, 100b and the circuit board 101 from both upper and lower sides.

When the lower movable plate 16 continues to rise further, the caulking chips 19a and 19b rise together with it, and conversely, the substrate holding plates 17a and 17b move upward.
is displaced downward while compressing the springs 21a and 21b. The crimping chips 19a, 19b pass through the through holes 22a, 22b of the board holding plates 17a, 17b and protrude above the upper surfaces of the plates 17a, 17b, and the electronic components have their upper ends protruding from the lower surface of the circuit board 101. 100a, 100b to be caulked forming part 103
comes into contact with the bottom surface of the When the crimping tips 19a and 19b move further upward, since the crimping tips 19a and 19b are heated, a part of the part 103 to be crimped is melted and deformed by the heat, and the crimping tips 19a and 19b are moved upward.
The circuit board 101 is thermally caulked by being pressed by the electronic component 100a.
, 100b are permanently mounted on the circuit board 101.

As described above, the preheating mechanism 2 is provided immediately before the crimping mechanism 3 to preheat the crimped forming portions 103 of the electronic components 100a and 100b temporarily attached to the circuit board 101, and then heat the parts 103 to be crimped. Caulking tip 19a, 1
The circuit board 101 is heated and pressed with 9b.
As it is clear from FIGS. 4(A) to 4(D) showing the forming process, the portion to be crimped 103 has a larger amount of heat q1 than the crimping tips 19a and 19b. Heat amount q2 of blowers 8a and 8b
(Fig.
A)), deformation due to crimping forming causes crimping tip 19a,
19b, but from the middle of the part to be crimped 103 (Figure (B)), and is crimped into a drum shape (Figure (C)). It can withstand reheating at a high temperature of 238° C. for 1 second during the solder dipping process.

Furthermore, by performing preheating, the temperature of the crimping chips 19a, 19b can be controlled over a wide range. For example, when molding the part 103 to be crimped made of PBT material with a diameter of 2 mm x 2 mm, Temperature control at 20°C will be a good thing. Note that by setting the time from preheating to the start of crimping to, for example, about 5 seconds, the part to be crimped 10 during the period from preheating to the start of crimping.
It is possible to suppress the temperature drop in No. 3 to a small level. Furthermore,
Preheating increases the amount of heat applied to the part 103 to be crimped, and since the molded shape becomes a drum shape, both the connector spacing d and the crimping diameter φ are stabilized, and crimping with a stable shape with little variation can be performed at high speed. Become.

It should be noted that the crimping mechanism 3 is not limited to the structure of the above embodiment, but may be any structure as long as it can perform thermal crimping. That is, the present invention
The structure of the crimping mechanism 3 itself is not a feature, but the feature is that a preheating process is provided in which the part to be crimped 103 is preheated as a preprocess of crimping.

[0021]

As described in detail above, according to the present invention, a preheating mechanism is provided immediately before the crimping mechanism, and the part to be crimped of the electronic component temporarily attached to the circuit board is preheated. By thermally staking the circuit board by heating and pressing with a post-heated staking chip, the deformation starts from the middle of the part to be swaged and the crimping is done in a drum shape. The resulting shape becomes thicker and can withstand reheating,
Both the connector spacing d and the caulking diameter φ are stabilized, and caulking forming into a stable shape with little variation is possible at high speed.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an embodiment of a thermal crimping device for electronic components according to the present invention.

FIG. 2 is an explanatory diagram of the operation of the preheating mechanism in FIG. 1;

3 is a schematic perspective view of the crimping mechanism in FIG. 1. FIG.

FIG. 4 is a process diagram of caulking molding in the present invention.

FIG. 5 is a side view showing a schematic structure of a conventional thermal crimping device.

FIG. 6 is a process diagram of caulking molding in a conventional example.

[Explanation of symbols]

1 Thermal caulking device of the present invention 2 Preheating mechanism 3 Caulking mechanism 8a, 8b Blower 10a, 10b Conveyor belt 18a, 18b Caulking head 19a, 19b Caulking chip 100, 100a, 100b Electronic component 101 Circuit board 103 Part to be caulked

Claims (1)

[Claims] 1. A preheating mechanism for preheating a part to be crimped of an electronic component inserted into a through hole of a circuit board; A thermal crimping device for electronic components, comprising a crimping mechanism that heats and presses the circuit board with a member.