JPS60124945A - Pellet bonder - Google Patents

Abstract

PURPOSE:To put a pellet and a stem into high-accurate positioning by a method wherein the title device is composed of an image processing unit including a camera recognizing the pattern of pellets, an operation unit discriminating the state of positioning of the pellet to the center of the stem on the basis of its result, and a correction mechanism correcting the pellet position on the stem according to the output of judgement. CONSTITUTION:On a positioning mechanism 3 incorporating a heater 4, the pellet 1 with the stem 2 fixed to the back with solder 13 is accurately mounted by using a collet 5. Next, a cooling pipe 14 is provided above the pellet 1 in an oblique direction, the tip of which is then covered with an illuminating system 6, and the camera 8 is arranged above this via optical system 7. Thereafter, the image signals of the pellet 1 obtained by the camera 8 are transmitted to the image processing unit 9, and the positional slippage of the pellet 1 off from the center of the stem 2 is calculated out by processing the output in the operation unit 10. Next, a position correcting machine 11 is operated on the basis of the result, and then the position of the pellet 1 is corrected by means of a position correcting pawl 12.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a pellet bonder that uses a brazing material to bond a V-bet and a stem (base), which are used for example in light receiving elements for optical communication, etc. In particular, the present invention relates to improvements in a mechanism for correcting the positions of pellets and stems.

[Background of the invention]

Generally, due to the nature of the light receiving element for optical communication, it is required that the pellet is aligned and fixed to the stem with high precision, but conventionally, this alignment has been done by detecting misalignment by visual inspection using a microscope. However, a method is used to manually correct the positional deviation. For this reason, there is a limit to the positioning accuracy, and to compensate for this, a screening process is required to determine whether or not the positions of both are accurate, which increases the number of man-hours. On the other hand, there is an automatic pellet bonder that mechanically determines the position of the pellets and fixes them together, but the positioning accuracy obtained here is about ±50 to 1100 tt, and it is difficult to improve the mechanical accuracy alone.
There is a problem in that the required positional accuracy of, for example, about ±20 μm cannot be achieved.

[Purpose of the invention]

An object of the present invention is to provide a pellet bonder that can position pellets and stems with high precision and reduce the number of manufacturing steps.

[Summary of the invention]

The present invention focuses on the fact that when the brazing material between the pellet and the stem is in a molten state, when an external force is applied to the pellet, the pellet moves on the stem. Based on the recognized pellet pattern, the pellet is placed at the center of the stem. A calculation unit that determines whether the pellet is attached or not is provided, and a correction mechanism that corrects the position of the pellet on the stem based on the judgment output of this calculation unit.The correction mechanism applies external force to the pellet while constantly recognizing the position of the pellet. is given and the position is corrected so that it becomes the center of the stem.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on examples.

FIG. 1 is an overall configuration diagram showing one embodiment of the present invention, and FIG. 2 is an enlarged view of the relationship among the pellet, stem, and deformation correction claw. In these figures, pellet 1 is placed on stem 2 via brazing material 13. The stem 2 is accurately held by a stem positioning mechanism 3 and appropriately heated by a heater 4. The pellets 1 are supplied and temporarily attached to the stem 2 by a collet 5.

On the other hand, an illumination system 6, an optical system 7, and a camera 8 are arranged above the stem 2, and the image signal of the pellet 1 received by the camera 8 is sent to an image processing section 9 where its pattern is recognized and further processed by calculation. In part 1O, the positional deviation of the stem 2 with respect to the center is calculated.

Then, the calculation result is given to the position correction mechanism 11,
The movement of this mechanism 11 is transmitted to the position correction claw 12.

Next, the overall operation will be explained.

First, the stem 2 is heated appropriately by the heater 4 in advance, and its center is held at an accurate position by the stem positioning mechanism 3. At this time, the brazing material 13 is already placed on the stem 2.

In this state, the pellet 1 is placed on the brazing material 13 by the collet (a jig that vacuum-adsorbs the pellet) 5,
Depending on the case, the pellet 1 is moved back and forth several times and placed in a manner of being rubbed 9, and when this is finished, the collet 5 is removed.

On the other hand, during this time, the illumination system 6 irradiates light from above the pellet 1 so that the pattern can be clearly discerned. As a result, an image of the pellet 1 is captured by the optical system 7 within a necessary range and is provided to the camera 8. The image of the pellet 1 captured by the camera 8 is converted into a video signal and input to the image processing section 9, where the patterns of the pellet 1 are recognized. This recognition result is given to the calculation unit 1o. Then, the calculation unit 1o calculates how far the pellet 1 is deviated from the center of the stem 2, and calculates the ff
i is applied to the position correction mechanism 11 to a value smaller than the current amount of deviation, the position correction claw 12 is driven, and external force IK is applied to move the position correction mechanism 11. After this, the position correction mechanism 1 and the correction claw 12 are withdrawn for a certain period of time. Then, the position of the beret is recognized again in the same way, and if the center is outside the required accuracy range, the same recognition and correction is repeated again.
The entire operation ends when a predetermined accuracy is achieved.

By the way, the camera 8 has, for example, 384 points in the horizontal scanning direction.
It is equipped with an image sensor consisting of a total of 187,776 pixels (489 pixels in the vertical scanning direction), which binarizes the pattern of pellet 1 according to its density, and outputs this binarized signal as a pellet pattern video signal. is configured to do so. Accordingly, the calculation unit for the amount of positional deviation of the pellet 1 in the calculation unit IO also corresponds to this resolution, and as a result, the positioning accuracy of the pellet 1 can be adjusted to ±2.
The discharge thickness can be set to 2.6 μm.

Depending on the type of brazing filler metal 13, auxiliary means may be used to fix the pellets 1 by blowing with N2 gas or air through the cooling pipe 14 to lower the Mi degree slightly.

If this method is used, high positional accuracy that cannot be obtained by the mechanical accuracy of the collet 5 alone can be obtained.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the position recognition and correction of pellets is automatically performed, which increases efficiency several times that of conventional manual work, and furthermore eliminates the process of sorting good and defective products. Furthermore, it is possible to improve the guarantee level of center accuracy. Therefore, it is extremely useful if used in the manufacture of light-receiving elements for optical communications, which require highly accurate positioning.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing one embodiment of the present invention, and FIG. 2 is an enlarged diagram showing the relationship among the pellet, stem, and position correction claw. DESCRIPTION OF SYMBOLS 1... Pellet, 2... Stem, 3... Stem positioning mechanism, 4... Heater, 5... Collet, 6...
...Lighting system, 7...Optical system, 8...Camera, 9...
・Image processing unit, lO... calculation unit, 11... position correction mechanism, 12... position correction claw, 13... brazing material, 14
...cooling pipe. Agent Patent Attorney Tatsuyuki Unuma

Claims (1)

[Claims] 1. An image processing section including a camera that recognizes the pattern of the pellets placed on the stem via the brazing material on the stem installed in the positioning mechanism having heating means; A calculation unit that determines whether or not the pellet is positioned at the center of the stem, and a correction mechanism that uses the determination output of the calculation unit to correct the position of the pellet on the stem based on the fact that the brazing material is in a molten state. Tenaru Pellet Bonder.