JPH07297535A - Laser soldering device of lead part and its method - Google Patents

Abstract

PURPOSE:To prevent a defective substrate with an alarm indicating the generation of a soldering defect from being sent to the next step by a method wherein, when a lead of a bonding tool is pressed down, its height is detected, and in comparison with a height of the bonding tool when the preceding lead is pressed down, a tool pressing mistake is detected. CONSTITUTION:A laser soldering device comprises a linear encoder 9 for detecting a height of a bonding tool 5; a distortion gauge 11 for detecting that the bonding tool 5 presses down a lead 2; and a controlling part 10 for controlling operations of an actuator 8 based on a readout value of the linear encoder 9. When the lead 2 being in a normal state on an electrode 4 is pressed down, a height of the bonding tool 5 is substantially constant. As the height in this normal case is different from that when the lead 2 is abnormal, a height of the bonding tool 5 when the lead 2 is pressed down is measured by the linear encoder 9, whereby a lead pressing mistake in the abnormal case can be detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser soldering apparatus and method for lead parts, and more particularly, a laser for lead parts which is bonded to electrodes on a substrate by irradiating a laser while pressing the leads of fine lead parts one by one with a bonding tool. The present invention relates to a soldering apparatus and method.

[0002]

2. Description of the Related Art A conventional laser soldering device for lead parts is described in Japanese Patent Application No. 039699 of 1993. This conventional device, as shown in FIG.
A tool part 1 for pressing the soldering leads 9 of the lead component 11 positioned on the substrate 7 one by one onto the electrode 10, a soldering lead 9 and a plurality of laser head parts 2 for irradiating only the electrode 10 with laser light. And the tool unit 1 and the laser head unit 2 both move up and down.

The holding part 6 positions and fixes the lead component 11 on the substrate 7. Next, the tool 9 is lowered to press the lead 9 against the electrode 10. The lead 9 may not contact the electrode 10 only by the positioning by the holding part 6, but the lead 9 is forcibly pressed by the tool part 1 so as to contact the electrode 10. Subsequently, the laser control unit 4 issues a laser irradiation command to the laser oscillator 5, and as shown in FIG. 3, the laser head 8 irradiates the laser beam 8 focused only on the soldered portion. The laser control unit 4 monitors the irradiation time, irradiates the amount of heat that melts the solder, and then stops the laser irradiation by the laser oscillator 5. The adjoining leads 9 are joined by moving the substrate 7 by the pitch dimension of the leads 9 by the stage unit 3.

[0004]

The above-described conventional laser soldering apparatus for lead parts does not have a means for detecting a soldering failure due to an error in the lead holding of the tool portion 1 caused by the bending of the lead of the part. Therefore, there is a possibility that the board including the soldering failure of the lead component may flow to the next manufacturing process, and an additional inspection process or the like is required to prevent this.

[0005]

According to the present invention, after positioning lead components on a substrate, the leads of the lead components are soldered by irradiating a laser beam while pressing the leads of the lead components one by one against the electrodes of the substrate. In a laser soldering device for lead components, a holder for holding the bonding tool, a guide for guiding the holder, an actuator for moving the holder along with the bonding tool along the guide, and the guide for the bonding tool are provided. A scale that measures a height that is a position in a guiding direction and a contact detector that detects that the bonding tool holds the lead, and the bonding tool holds the lead by the contact detector. Based on the measured value of the scale when And judging the lead holding mistakes serial lead.

[0006]

The present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an embodiment of a laser soldering apparatus for lead parts according to the present invention.

The laser soldering apparatus for lead components shown in FIG. 1 is a device for positioning the lead components 1 on the substrate 3 and then irradiating a laser while pressing the leads 2 one by one to solder the electrodes 4 on the substrate 3. Then, lead 2 of lead component 1
Bonding tool 5 for pressing the electrode 4 onto the electrode 4 of the substrate 3
A holder 6 that holds the bonding tool 5, a guide 7 that slidably supports the holder 6 and guides the bonding tool 5 up and down, and an actuator 8 that also includes a voice coil that drives the bonding tool 5. Linear encoder 9 for detecting the height of the bonding tool 5
And a strain gauge (contact detector) 11 installed on the holder 6 for detecting that the bonding tool 5 holds the lead 2 by the bending strain of the holder 6, and the operation of the actuator 8 based on the reading value of the linear encoder 9. Control unit 1 for controlling
0 (details omitted) is included.

The height of the bonding tool 5 when the lead 2 which is normally positioned on the electrode 4 is pressed is almost constant, but the height and the lead 2 in this normal case are bent and the electrode 4 is bent. When the bonding tool 5 comes into direct contact with the electrode 4 without the lead 2 positioned above, when the bonding tool 5 presses the lead 2 with two overlapping electrodes 4, or when the bonding tool 5 is applied to the electrode 4. Since the height of the bonding tool 5 in the case of abnormalities such as when the applied solder is too thick is different, measuring the height of the bonding tool 5 when the lead 2 is pressed by the linear encoder 9 causes these abnormalities. In this case, it is possible to detect a lead holding error.

In the bonding operation of soldering the lead 2 to the electrode 4, the actuator 8 is driven by a command from the control unit 10 to lower the bonding tool 5 via the holder 6, and the bonding tool 5 causes the lead 2 of the lead component 1 to move. Is detected by the strain gauge 11 and then irradiated with a laser (not shown in FIG. 1) to
Etc. are sequentially executed for a large number of leads arranged in lead parts. In the bonding operation for each lead, the tool height when the contact with the lead 2 of the bonding tool 5 is detected by the strain gauge 11 is measured by the linear encoder 9 and read into the control unit 10. Is compared with the height of the bonding tool 5 at the time of contact with the lead bonded to the electrode 4 in the immediately preceding bonding operation, and if there is a change of a certain threshold value or more between these, a lead pressing error is caused. It is determined that there is.

[0011]

As described above, the laser soldering method for lead parts according to the present invention detects the height of the bonding tool when the lead is pressed, and compares it with the height of the bonding tool immediately before pressing the lead. Since it is possible to detect a tool pressing error, it is possible to prevent a defective board from flowing to the next process by generating an alarm for defective soldering.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

FIG. 2 is a side view of a conventional laser soldering device for lead components.

FIG. 3 is an enlarged perspective view showing a lead portion in the conventional laser soldering device for the lead component shown in FIG.

[Explanation of symbols]

 1 Lead Component 2 Lead 3 Board 4 Electrode 5 Bonding Tool 6 Holder 7 Guide 8 Voice Coil Motor 9 Linear Encoder 10 Controller 11 Strain Gauge

Claims (4)

[Claims] 1. A laser soldering apparatus for a lead component, comprising: positioning a lead component on a substrate and then radiating a laser beam and soldering the leads while pressing the leads of the lead component one by one against electrodes of the substrate with a bonding tool. A holder for holding the bonding tool, a guide for guiding the holder, an actuator for moving the holder along with the bonding tool along the guide, and a position of the bonding tool in a direction in which the guide guides. A scale for measuring the depth and a contact detector for detecting that the bonding tool holds the lead, and the scale of the scale when the bonding tool detects that the bonding tool holds the lead. Based on the measured value, A laser soldering device for lead parts, which is characterized by determining a soldering. 2. Laser soldering of lead components for positioning the lead components on the substrate and then soldering by a bonding operation of radiating laser light while pressing the leads of the lead components one by one against the electrodes of the substrate with a bonding tool. A method of laser soldering a lead component according to the method, wherein a lead pressing error of the lead is determined based on a height of the bonding tool from the substrate when the lead is pressed against the electrode. 3. The laser soldering apparatus for a lead component according to claim 1, wherein the contact detector is a strain gauge that detects strain of the holder. 4. If the height of the bonding tool from the substrate when the lead is pressed against the electrode is changed by a certain threshold value or more in comparison between the immediately preceding bonding operation and the current bonding operation. The laser soldering method for a lead component according to claim 2, wherein it is determined that there is a lead pressing error.