JPS6166144A - Soldering-strength examining method - Google Patents

Abstract

PURPOSE:To detect the separation of a lead wire and an element accurately, by applying a force to one lead wire in the direction perpendicular to the main surface of the element of an electronic part, and then inserting a wedge shaped tapered pushing terminal between a pair of the lead wires. CONSTITUTION:Lead wires 32a and 32b are held by grooves 13a and 13b of a receiving jig 12 and a lead-wire pushing piece 16. A force is applied to the lead wire 32b by a pushing terminal 17 in the direction C perpendicular to the main surface of an element 30 from the side of the element 30. The lead wire 32b is soldered to a main surface 30b of the element 30, which is the opposite side with respect to the pushing terminal 17. Therefore, the force is applied in the direction shown by an arrow D on the soldered part of the element 30 of an electronic part and the lead wire 32b by the pushing terminal 17.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a soldering strength testing method, and more particularly to a soldering strength testing method for testing the connection strength of a lead wire soldered to an element of an electronic component, for example.

(Prior Art) FIG. 6 is a perspective view showing an example of a conventional soldering inspection device. This inspection device 10 includes a support jig 12 made of insulating resin. This receiver is located at the top and bottom of the jig 12.
Projections 12a and 12b are formed respectively, and two grooves 14a and 14b are formed in the side end surface of the upper projection 12a in the thickness direction thereof. Grooves 14a and 14
b, one lead wire 32a soldered to one main surface 30a of the element 30 of the electronic component, and the other lead wire 32b soldered to the other main surface 30b, respectively.
is inserted. In this state, the lead wire presser 16 is brought into contact with the side end surface of the upper protrusion 12a, whereby the receiver is held in the groove 14 of the jig 12. Lead wires 32a and 32b are held between a and 14b.

At this time, the lower protrusion 12b of the jig 12 serves as the receiver, and the lead wire 32a sandwiched between the jig 12 and the lead wire holder 16 serves as the receiver.
and 32b, the receiver prevents movement toward the jig 12.

The receiver is provided with a detection terminal 18 movable in the axial direction of the jig 12 so as to face the intermediate portion between the two protrusions 12a and 12b (the intermediate portion between the lead wires 32a and 32b). The detection terminal 18 is made of a conductive material, such as metal, and has a tapered wedge shape that is wider than the distance between the lead wires 32a and 32b. The detection terminal 18 is inserted with its tip between the lead wires 32a and 32b in a direction perpendicular to the main surface of the element 30, for example, using a certain elastic force from a spring (not shown). . In this case, if lead wire 32a or 32b and element 3
0, the soldered part will be peeled off by the pressing force of the detection terminal 18, and the detection terminal 18 will not connect between the lead wires. As it passes, the receiver contacts an electrode 20 formed in the middle portion of the jig 12. Electrode 18 of this detection terminal 18
A defective solder row can be detected by a short circuit or electrical continuity between a and the electrode 20 of the jig 12.

(Problems to be Solved by the Invention) In the conventional inspection device, the detection terminal 18 is inserted between the lead wires 32a and 32b, and the detection terminal 18 is inserted into the lead wire in a direction parallel to the main surface of the element 30, that is, in the direction indicated by the arrow in FIG. A defect signal is obtained by applying force in the direction indicated by A to forcibly peel off the weakly soldered parts of the lead wires 32a and 32b and the element 30, and bringing the detection terminal 18 into contact with the electrode 20. However, inspection errors have occurred with conventional equipment. That is, when the hardness of the lead wire material is low, the detection terminal 18 bends the lead wires 32a and 32b as shown by arrow A in FIG.
Even if 2a and 32b are firmly soldered to the element 30, the detection terminal 18 passes between the deformed lead wires and eventually comes into contact with the electrode 20.

Therefore, the main object of the present invention is to provide a highly reliable soldering strength testing method that is free from testing errors.

(Means for Solving the Invention) This invention first applies a force to one of the lead wires in a direction perpendicular to the main surface of an element of an electronic component, and then applies a force to one side of the lead wire in a direction perpendicular to the main surface of an element of an electronic component, and then applies a force to one side of the lead wire in a direction perpendicular to the main surface of an element of an electronic component. A soldering strength testing method in which a wedge-shaped terminal is inserted between a pair of lead wires in a direction perpendicular to the main surface of the element to detect whether the soldered part between the lead wire and the element has peeled off. It is.

(Effects of the Invention) According to this invention, inspection errors do not occur. In other words, in this invention, when a force is applied to the lead wire in a direction perpendicular to the main surface of the element, the force required to peel off the soldered part of the same strength is the same as that of the conventional lead wire. This is based on the fact that it has become clear that it is weaker than when it is applied in a direction parallel to the main surface of the . Therefore, if the soldering strength is weak, the lead wire can be reliably peeled off from the electronic component element, and if the soldering strength is higher than that, a large force that may cause deformation of the lead wire can be applied. Since it is not added, it remains as it is. In other words, in this invention, even if the soldered part is forcibly peeled off, there is no need to apply a large force that would deform the lead wire, so false detection due to deformation of the lead wire is eliminated and reliability is improved. It will improve.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

(Example) FIG. 1 is a perspective view showing an embodiment of the invention.

The inspection device 100 of this embodiment, like the conventional example,
The receiver includes a jig 12 having an upper protrusion 12a and a lower protrusion 12b. In this embodiment, the receiver is the jig 12.
Two sets of grooves 13a and 13b and one set of grooves 14a and 14b are formed at intervals in the length direction on the side end surface of the upper protrusion 12a, and in the portion of one set of grooves 13a and 13b, first, A force is applied to forcibly peel off the soldered part, and then the other set of grooves 14a and 14b is inspected to see if it has peeled off. For this purpose, one lead wire 32a soldered to one main surface 30a of the element 30 of the electronic component is placed in one groove 132 and 14a of each set, and the other lead wire 32a is soldered to one main surface 30a of the element 30 of the electronic component. The other glued wire 32b soldered to the main surface 30b is fitted. Each set of grooves 13a
and 13b and 14a and I 4. The lead wires 32a and 32b are respectively fitted into the lead wires 32a and 32b.
The lead wire 32 is held by a lead wire holder 16 (not shown in FIG. 1), and the lower protrusion 12b is held by the lead wire 32.
supports the lower portions of a and 32b. The lead cotton 32a in the groove 138 is supported by contacting or abutting the support portion 12C formed on the jig 12 over almost its entire length.

In order to forcibly peel off the soldered portion with a strength lower than that at the position of one set of grooves 13a and 13b, the presser terminal 17 is placed opposite to the lead wire 32b sandwiched between the groove 13b and the lead wire presser 16. Moreover, it is provided so as to be movable in its axial direction. In order to apply force to the lead wire 32b held by the groove 13b in a direction perpendicular to the main surface of the element 30, the holding terminal 17 is provided with a cam (not shown), for example, in the same way as the detection terminal 18 described later. , the element 30 is urged with a constant force to move in its axial direction.

Further, a detection terminal 18 is provided to be located between the lead wires 32a and 32b held by the grooves 14a and 14b and to be movable in the axial direction thereof, in order to detect whether the soldered portion is peeled off. . This terminal 18
is made of a conductive material, such as metal, like that of the conventional device, and has a tapered wedge shape that is wider than the spacing between the leads 32a and 32b.

Here, the detection terminal 18 will be explained in some detail with reference to FIG. Note that although only the detection terminal 18 is shown in FIG. 2, the presser terminal 17 is also configured in the same manner.

The detection terminal 1 is housed in a bottomed hollow cylindrical case 19 having a through hole on one end surface, and its tip protrudes forward through the through hole. A coil spring 19a is provided between the rear end of the detection terminal 18 and the other end of the case 19,
Thereby, the detection terminal 18 is urged toward its tip. The coil spring 19a comes into contact with the tip of a spring pressure adjusting screw 19b screwed into a screw hole at the other end of the case 19. Therefore, by displacing this spring pressure adjusting screw 19b, the distance between its tip and the rear end of the terminal 18, that is, the elastic force of the coil spring 19a can be adjusted.

When the entire case 19 is moved in the direction of arrow C by a cam (not shown), the tip of the detection terminal 18 moves accordingly and is inserted between the lead wires. The presser force is adjusted by the spring 19a, that is, the spring pressure adjusting screw 19b. If the spring 19a is compressed by the spring pressure adjustment spring 19b, its strength will be strong, and if the spring 19a is not compressed much, its strength will be weak.

An electrode 18a is electrically connected to the detection terminal 1B, and an electrode 20 is also formed on the jig 12 of the receiver facing the detection terminal 18. Between these two electrodes 18a and 20 is a lamp 22. Buzzer 24 and power supply 26 are connected in series. If there is a soldering defect, the two electrodes 18a and 20 are electrically connected, forming a closed circuit including the above-mentioned series connection, and the lamp 2
2 lights up and the buzzer 24 sounds to notify the operator of the occurrence of a defect.

Note that the means for notifying the soldering defect may be only by lighting a lamp or sounding a buzzer, and furthermore, a signal outputted in response to contact between the electrodes 18a and 20 may be used to mark defective products. The circuit configuration for defect detection may be arbitrarily changed as necessary, such as cutting the lead wire or stopping the inspection process.

Next, an inspection method using the inspection apparatus of this embodiment will be explained.

First, the lead wires 32a and 32b are sandwiched between the grooves 13a and 13b of the receiving jig 12 and the lead wire presser 16. As shown in FIG. 3, the presser terminal 17 connects the lead wire 32b soldered to the main surface 30b of the element 30 opposite to the presser terminal 17 from the element 30 side in a direction perpendicular to the main surface, that is, Apply force in the direction shown by arrow C in Figure 3. Therefore, force is applied by the presser terminal 17 to the soldered portion between the electronic component element 30 and the lead wire 32b in the direction indicated by the arrow in FIG.

If a force is applied in the direction of the arrow in Fig. 4, that is, in the direction of arrow C in Fig. 3, the force will be applied parallel to the main surface of the element, as in the conventional case, assuming that the soldered part of the same strength is to be peeled off. Compared to adding in the direction (direction to the arrow in Figure 7),
It may be weaker.

This is because the element 30 and the lead wires 32a and 32
This is because the peel strength of the soldered portion with b is weaker in a direction perpendicular to the main surface of the element 30 than in a direction parallel to the main surface. According to the inventor's experiments, in order to separate lead wires connected with the same soldering strength, applying force in a direction perpendicular to the main surface of the element is better than applying force in a direction parallel to the main surface. It was confirmed that less than one third of the force was required. Therefore, since no more force than necessary to forcibly separate the element and the lead wire is applied to the lead wire, the lead wire 32b can be used without bending the lead wire 32b if the strength is below a certain level. 32b
can be reliably peeled off from the element 30, and if no peeling occurs even with that force, the soldered portion can be treated as a good product.

By adjusting the urging force of the holding terminal 17 as described above, the bonding strength at which the terminal 17 should be peeled off, that is, the strength at the boundary where the terminal should be treated as a good product or a defective product, can be set as appropriate.

Next, the element 30 is moved in the direction shown by arrow B in FIG.
and 14b and a lead wire presser 16 (not shown in FIG. 1).

Then, as shown in FIG.
It is moved in the direction shown by arrow E in the figure, and its tip is inserted between lead wires 32a and 32b. In this case, if the lead wires 32a or 32b were peeled off from the element 30 in the previous step, the gap between the lead wires 32a and 32b would become wider as the detection terminal 18 is inserted.
The detection terminal 18 contacts the electrode 20, the lamp 22 and the buzzer 24 are activated, and the electronic component is treated as a defective product. Conversely, if the lead wire is not separated from the element even after the forced determination step using the presser terminal 17,
The lamp 22 and buzzer 24 do not operate, and in that case, the product is treated as a non-defective product.

In the -1 series of embodiments, two terminals are used to perform each step. However, one terminal may be used in common if possible.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention. FIG. 2 is a sectional view showing the internal structure of the detection terminal of the embodiment shown in FIG. FIG. 3 is an illustrative view for explaining the state in which force is applied to the lead wire by the presser terminal. FIG. 4 is a perspective view showing the direction of force applied to the lead wire by the presser terminal. FIG. 5 is an illustrative view for explaining a state in which the detection terminal is inserted between the lead wires. FIG. 6 is a perspective view showing an example of a conventional bonding strength testing device. FIG. 7 is a perspective view showing the direction of force applied to the lead wire in a conventional device. In the figure, 100 is a soldering strength testing device, 12 is a jig, 13a, 13b, 14a and 14b are grooves, 1
6 is a lead wire holder, 17 is a holder terminal, 18 is a detection terminal,
19a is a spring, 19b is a spring pressure adjustment spring, 18a, 20
22 is an electrode, 22 is a lamp, 24 is a buzzer, 30 is an electronic component element, and 32a and 32b are lead wires.

Claims (1)

[Scope of Claims] Soldering of lead wires of an electronic component having one lead wire soldered to one main surface of an element of the electronic component and the other lead wire soldered to the other main surface of the element. A soldering strength testing method for testing the strength of a soldering wire, the method comprising: applying force to the lead wire from the element side in a direction perpendicular to the main surface of the element; A soldering strength testing method comprising the step of inserting a wedge-shaped terminal between the lead wires in a direction perpendicular to the main surface of the element to detect peeling of the lead wires.