JPH0413613Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is a device for determining the wire diameter of the lead wire of an axial lead type electronic component in which the lead wire is led out 180 degrees in the opposite direction from the main body of the component. The present invention relates to a device for determining whether solder plating of a wire is good or bad.

BACKGROUND OF THE INVENTION Axial lead type electronic components such as diodes and resistors are generally solder-plated to improve solderability when mounted on a printed circuit board or the like.
An example of such an electronic component, such as an axial lead type diode, is shown in FIG. 10, where 1 is the component body, and 2, 2 are two lead wires extending 180 degrees in opposite directions from both ends of the component body 1. . Lead wire 2,
2 constitutes a slug lead having heat sink parts 3, 3 at one end, and 2 in the glass sleeve 5.
A diode pellet 4 is sandwiched between two heat sink parts 3, 3, and a glass sleeve 5 is welded to the outer periphery of the heat sink parts 3, 3 to form a component body 1.
Each lead wire 2, 2 is a conductive wire such as a copper-coated steel wire, and a solder plating layer 6, 6 is applied to the surface thereof. The solder plating layers 6, 6 are formed on the tip side from a portion several mm away from the end of the component body 1 in the following manner.

As shown in FIG. 11, the diode 7 is suspended vertically with the tip of one lead wire 2 supported by a clamper 8, and the other lead wire 2 is immersed up to the middle part in the flux liquid 9. As shown in FIG. 12, the component body 1 is immersed in a solder melt 10, floating at a height of several mm above the solder liquid level. Here, if the entire length of the lead wire 2 is immersed in the solder liquid 10, the glass sleeve 5 may be damaged, so solder plating is performed as shown in FIG. 12. Similarly, the other lead wires 2 are also subjected to flux treatment and solder plating treatment.

In such processing, the lengths l and l' of the non-solder plated portions 2b and 2b formed on the lead-out root portions 2a and 2a of the lead wires 2 and 2 may vary due to defects such as flux creep-up. be.
If these lengths l and l' exceed several mm, it may cause soldering defects when mounted on a printed circuit board, so the lengths l and l' of these non-solder plated parts 2b and 2b are several mm.
mm or less, and quality is determined after soldering. Conventionally, this discrimination was performed by visual inspection by an operator, but this discrimination had the following problems.

Problems to be solved by the invention The lead wires 2, 2 of the diode mentioned above have a wire diameter of about 400 μm, and the thickness of the solder plating layers 6, 6 is about 400 μm.
Since it is small at about 25μm, the non-solder plated part 2b,
It is difficult to visually determine whether or not 2b is within the allowable range, resulting in a lack of accuracy. In addition, such visual discrimination needs to be performed for the left and right good lead wires 2, 2, and the workability is extremely poor.
Further, if this work was continued, the operator's eyes would become tired, resulting in a significant decrease in work efficiency and frequent discrimination errors.

Means for Solving Problems The present invention is a method for determining whether the solder plating layer of an axial lead type electronic component having solder-plated lead wires is well formed up to a predetermined location at the lead-out root portion of the lead wires. The purpose of the present invention is to provide a device that can automatically and continuously perform discrimination, and includes a component suction unit that appropriately suctions and positions and holds the root portion of a lead wire of an axial lead type electronic component on a conductive suction surface; The above object is achieved by a lead wire diameter determining device that includes a probe that moves parallel to the suction surface at a predetermined interval, and a continuity detection section that detects continuity between the suction surface and the probe.

Function The device according to the present invention fixes and positions the root part of the lead wire of an axial type electronic component on the suction surface, and sets the root part of the lead wire of an axial type electronic component to a suction surface parallel to the suction surface, which is larger than the diameter of the lead and smaller than the diameter of the solder-plated lead. The quality of the solder plating is determined by moving the probe at a predetermined interval and detecting whether the probe comes into contact with the suction surface via the lead and by detecting continuity between the probe and the suction surface.

Embodiment An example of an apparatus for determining the lead wire diameter of the electronic component 7 shown in FIG. 10 will be described below with reference to FIGS. 1 to 6.

In FIGS. 1 to 6, reference numeral 11 denotes a component suction unit that sequentially positions and suction-holds electronic components 7 having lead wires made of magnetic material one by one. L-shaped stepped portions 13, 1 are provided on the upper front surfaces of the opposite side walls 12', 12' of the block 12.
3 is formed, permanent magnets 14, 14 are embedded in the lower part of the vertical surfaces of the stepped portions 13, 13, and electrode plates 15, 15 are fixed to the front surfaces of the permanent magnets 14, 14. Opposite side wall 12' of insulating block 12
12' is set to be slightly longer than the length of the component body 1 (glass sleeve 5) of the electronic component 7, and the electronic component 7 is placed between the component body 1 and the side walls 12', 1 from above.
2', and connect the base portions 2a, 2a of the lead wires 2, 2 at both ends to the bottom surfaces of the stepped portions 13, 13 and the electrode plate 1.
The permanent magnets 14,
14 and electrode plates 15, 15, which are magnetically attracted to conductive attraction surfaces m and 15, and are held in position.

Reference numerals 16 and 16 indicate probes made of two metal conductors that are attached to the component suction section 11 and are arranged so as to be movable up and down along the front surfaces of both side walls 12' and 12' of the insulating block 12. Both probes 16, 16 move up and down with a fixed stroke in synchronization, and both probes 16, 1 move at the top dead center position.
The upper part of the probe 6 faces the corresponding electrode plate 15, 15 in parallel at a constant interval, and both probes 16,
16 is located below the bottom surfaces of the stepped portions 13, 13.

Reference numeral 17a denotes a first continuity detection unit 1 that applies an appropriate voltage between one electrode plate 15 and one probe 16 appropriately opposed to the electrode plate 15 to detect the continuity state between the two.
Reference numeral 7b is a second continuity detection section that applies a voltage appropriately between the remaining pair of electrode plates 15 and probe 16. The first and second continuity detection sections 17a and 17b are the probe 16,
16 rises to the top dead center, the quality of the solder plating at the root portions 2a, 2a of both lead wires 2, 2 is determined as described later.

Reference numeral 18 denotes a component supply unit that intermittently supplies electronic components 7 one by one to the component suction unit 11. For example, it is arranged above the insulating block 12 and drops the electronic components 7 one by one toward the stepped portions 13, 13. This is a supply conveyor. Reference numeral 19 denotes a component ejecting section for taking out the electronic component 7 whose wire diameter has been determined at the stepped portions 13, 13;
For example, a pair of first electromagnets 20, 20 and a second electromagnet, each two of which are arranged with a step in front of both ends of the lead wires 2, 2 of the electronic components 7 on the steps 13, 13,
It is composed of electromagnets 21, 21. The upper first electromagnets 20, 20 are determined to be non-defective based on the conduction signals from both the continuity detectors 17a, 17b, and the step portions 13, 13 are determined to be good.
The upper electronic component 7 is attracted by the magnetic attraction of the lead wires 2, 2. The lower second electromagnets 21, 21 determine that it is a defective product if both or one of the conduction detecting parts 17a, 17b are not conductive, and attract the electronic components 7 on the stepped parts 13, 13. The electronic components 7 attracted by the first electromagnets 20, 20 naturally fall when the first electromagnets 20, 20 are de-energized, and the good product removal guides 22, 2
The second electromagnet 21, etc. is discharged to an external good product storage box (not shown) etc.
The electronic component 7 attracted by the second electromagnet 21,
21, the product falls naturally and is discharged to an external defective product storage box (not shown) or the like.

The dimensional relationship between the component suction portion 11 and the probes 16, 16 will be explained based on FIGS. 4 to 6. First 2
The two electrode plates 15, 15 and the probes 16, 16 face each other at the base portions 2a, 2a of both lead wires 2, 2 of the electronic component 7, as shown in FIG. Assuming that the maximum allowable length of the plated portions 2b, 2b is _L0 , they face each other at a minute portion inside the component body 1 with _L0 as the boundary. In addition, the suction surfaces m, m on the front surface of the electrode plates 15, 15 and the probes 16, 1
Let D ₀ be the opposing distance between the lead wires 2 and 2, d ₁ be the diameter of the non-solder plated portions 2b of the lead wires 2, and d ₂ be the diameter of the solder plated portions, then the relationship d ₁ <D ₀ <d ₂ holds. Set. Specifically, when d ₁ = 400 μm, the plating thickness is
If 25 μm and d ₂ =450 μm, D ₀ is set to about 425 μm.

Next, the operation of the above embodiment will be explained. When one electronic component 7 is supplied from the component supply section 18 to the stepped sections 13, 13 of the component suction section 11 and held in position,
The two probes 16, 16 simultaneously rise to face the suction surfaces m, m which have suctioned the root portions 2a, 2a of the lead wires 2, 2. Now, assuming that the solder plating of both lead wires 2, 2 is good, the solder plating layer 6,
6 is formed to the inside of the component body 1 at a distance L _{0 ,} so both probes 16 , 16 come into contact with both lead wires 2 , 2 due to the relationship D ₀ <d ₂ as shown in FIG. 5 . In this state, the continuity detectors 17a, 17b detect the current flowing between the electrode plates 15, 15 and the probes 16, 16, which indicates that both the lead wires 2, 2 are successfully soldered. Detected.
After that, the voltage application is stopped, both probes 16, 16 are lowered, and the first electromagnets 20, 20 for taking out non-defective products are activated to take out non-defective solder-plated electronic components.

In addition, when the component suction unit 11 is supplied with an electronic component 7 in which the solder plating of both lead wires 2, 2 is defective, or one of them is defective, when the probes 16, 16 are raised, D ₀ > d ₁ . In this connection, as shown in FIG. 6, both or one of the probes 16, 16 does not come into contact with the lead wires 2, 2, and no current is applied.
This automatically determines whether the solder plating is defective. In this case, the second electromagnets 21, 21 for removing defective products are activated to remove defective products.

Next, other embodiments of the present invention are shown in FIGS. 7 and 8.
This will be explained with reference to FIG.

FIG. 7 shows a modified example of the probe, and the probes 16', ₁₆ ' in _FIG . There is no planar structure, and both surfaces n ₁ and n ₂ are used depending on the type of wire diameter of the lead wires 2 and 2.
In this way, it can be applied to electronic components having two types of lead wire diameters.

FIG. 8 shows a modification of the insulating block, and the insulating block 12'' in FIG. This insulating block 12'' and the probe 1 in Fig. 7 can be changed.
By combining 6' and 16', it is possible to handle a wider variety of electronic components.

Figure 9 shows an example of changing the parts ejection method.
The component suction part 11 is arranged diagonally to form the stepped parts 13, 13.
Air nozzle 23 with electronic component 7 installed above
It is designed to be discharged to the outside using an air jet from the inside. In this case, the electronic components 7 are sorted into good and defective products by changing the air jet pressure from the air nozzle 23 in two stages and dividing the electronic components 7 into upper and lower portions of the guide 24 as shown by the two broken line arrow directions in FIG. It is done by blowing.

Further, although not shown, the component suction means in the component suction section is not limited to a permanent magnet, but may be a structure in which a lead wire is simply fitted into a V-shaped groove or a structure using vacuum suction.

C. Effects of the invention According to the invention, the solder plating of the lead wires of axial lead type electronic components can be continuously and automatically checked using a simple device, and the automation increases accuracy and greatly improves reliability. improve. In addition, since the lead wire is discriminated by the root portion, even if the lead wire is slightly deformed, it does not pose a problem, and it is possible to provide a product with excellent practicality.

[Brief explanation of drawings]

1 and 2 are a side view and a plan view showing an embodiment of the present invention, FIG. 3 is an enlarged perspective view of the main part of FIG. 1, and FIG. 4 is a partially enlarged front view of FIG. 5 and 6 are cross-sectional views taken along line X-X in FIG. 4, and FIGS. 7, 8, and 9 illustrate three other embodiments of the present invention. They are a partial side view, a partial plan view, and a side view. FIG. 10 is a side view of the axial lead type electronic component, and FIGS. 11 and 12 are cross-sectional views for explaining the solder plating process of the electronic component of FIG. 10. 1... Part body, 2, 2... Lead wire, 2a,
2a...root portion, 7...electronic component, 11...component suction section, m, m...suction surface, 16, 16... probe, 17a, 17b...continuity detection section.

Claims (1)

[Scope of utility model registration request] A component suction unit that properly positions and holds the lead wire of an electronic component whose lead wire is led out in a direction 180 degrees opposite to the component body on a conductive suction surface; 1. A lead wire diameter determination device for an electronic component, comprising: a moving probe; and a continuity detection section that detects continuity between the suction surface and the probe.