JP2001300429A - Sphere sorting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make certainly sortable bad spheres such as W-balls or the like mixed in extremely small spheres manufactured by an atomizing method. SOLUTION: A V-groove 1 is provided to a chuter 1 arranged so as to be inclined downward in a forward direction and spheres to be sorted are charged in the groove to apply directionality to the movement of the spheres. By this constitution, good spheres roll down at a high speed and bad spheres don't roll down to slip down at a slow speed and a difference is generated between the carrier of both spheres discharged from the chuter. Good and bad spheres are sorted by a sorting plate 2 on the basis of the carry difference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sphere selecting apparatus for selecting defective spheres mixed in non-defective spheres by utilizing a difference in flight distance caused by rolling and sliding.

[0002]

2. Description of the Related Art Most metal microspheres having a diameter of less than 1 mm are manufactured by an atomizing method. The atomization method sprays molten metal in a mist state in an inert atmosphere,
This is a processing method of turning scattered particles into spheres with surface tension.

[0003] The extremely small balls obtained by the atomizing method include defective products called W balls. The W ball is an irregular shaped ball formed by welding two or more particles during solidification. FIG. 10 shows a main form of the W ball.

If the microspheres produced by the atomizing method are, for example, bonding chips for electronic components, the inclusion of the above-mentioned W balls having different volumes will cause defective bonding, which is removed. Is required.

However, most of the three types of W balls shown in FIG. 10 have an outer diameter in a specific direction equal to a good product diameter.
In some cases, it cannot be removed by a sieve sorter using a mesh screen or a roller sorter that sorts by using a gap between rollers.

As shown in FIG. 11, there is also a method of selecting W balls based on a difference in the rolling direction of a sphere B on a flat inclined plate A (inclination selection method). difficult. In this inclined sorting method, the true sphere is shown in FIG.
As shown in (1), it rolls straight down on the inclined plate A.
On the other hand, the W ball rolls sideways when there is a circumferential difference between two contact portions with the inclined plate or when the W ball is placed obliquely on the inclined plate A as shown in FIG. The W balls are selected based on the difference in the rolling direction. In this method, as shown in FIG. 11C, when the twin spheres have the same diameter and the whole posture is not inclined, the cylinder is rolled. In the same situation as before, it rolled straight down and could not be sorted out.

[0007] Therefore, an object of the present invention is to eliminate the drawbacks of the inclined sorting method and to ensure that defective spheres can be sorted by this method.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, there is provided a shooter having a downward slope before a sphere to be sorted is placed and rolled down, and a shooter which normally rolls down on the shooter and forwards the shooter. A sorting device is constructed by combining a good sphere that draws a parabola and falls, and a sorting plate that places and sorts a defective sphere that slides down on the shooter and falls near the shooter between the falling points of both spheres. The chute of the device is provided with a vertical groove into which the sphere enters, and the sphere moving in the vertical groove gives directionality.

Preferred forms of such a sorting device are listed below. (A) A vibrator for vibrating the shooter is provided. (B) The vertical groove is formed as a V-shaped groove, and the groove bottom of the V-shaped groove is formed as an arc surface or a flat surface to reduce the distance from the surface of the sphere flowing into the groove to the groove bottom. (C) A plurality of vertical grooves are provided in parallel. (D) When there is a land between adjacent flutes, the land is inclined so as to descend toward the flute. (E) The tilt angle of the shooter is set to 1 degree or more and 30 degrees or less.

[0010]

When a longitudinal groove is provided in the shooter, the moving direction of the sphere is regulated in one direction by the guiding effect of the groove, and a good sphere rolls straight down, and a defective sphere such as a W ball slides down without rolling. The sliding speed is slower than the rolling speed of the sphere, and the difference in speed causes a difference in the flight distance between a good sphere and a defective sphere. Bad spheres fall near the shooter, and good ones fall farther than the bad spheres. Therefore, a defective sphere can be selected by arranging the separation plate between the two drop points.

When the shooter is vibrated, the defective sphere slides down even if the inclination angle of the shooter is small. The vibration at this time is preferably in the front-rear direction, since there is a possibility that the sphere may jump on the shooter if the vibration is in the vertical direction.

The vertical groove is preferably a V-shaped groove capable of coping with a variation in the diameter of the selected sphere. In particular, the V-groove in which the groove bottom is close to the surface of the sphere by adopting the above-mentioned configuration (b) is shown in FIG.
The W ball having the shape of (b) can be reliably selected by preventing rolling.

Further, as the number of flutes increases, the number of spheres selected simultaneously increases, and the work efficiency increases. In addition, when a plurality of vertical grooves are provided at intervals, if the width of the land generated between the grooves is large, the sphere may fall without flowing into the groove, so the slope that descends toward the vertical groove on the land may be inclined. It is recommended that the sphere on the land be forcibly guided into the flute.

In addition, the upper limit of the inclination angle of the shooter is 3
It is preferable to set it to about 0 to 35 degrees. The inclination angle is 35
Exceeding the degree, there is no distance difference between the drop point of good and bad products,
Sorting becomes difficult.

[0015]

1 and 2 show an embodiment of a sorting apparatus according to the present invention. This sorting device is a shooter 1
And a vibrator 3 for slightly vibrating the shooter 1 back and forth.

The shooter 1 has a straight V
A plurality of grooves 5 are provided in parallel. The main body 4 has an enclosing wall 6 standing on three sides excluding the front edge. Further, the exemplary shooter 1 is pivotally attached to the upper ends of the front leg 7 and the rear leg 8 so as to be attached, and the height of the rear leg 8 is changed by the adjuster 9 so that the inclination angle θ can be adjusted.

The sorting plate 2 is provided in front of the chute 1 at a predetermined distance. The separation plate 2 may be fixed at a fixed position, or the separation distance from the shooter may be finely adjusted.

The sorting apparatus thus constructed is preferably used by disposing a collection box 10 for defective spheres and a collection box 11 for good spheres before and after the separation plate 2.

When the sphere to be sorted is supplied onto the main body 4 while the shooter 1 is vibrated by the vibrator 3, the sphere B flows into the V-groove 5 as shown in FIGS. I do. At this time, a good sphere rolls down at a high speed, and a defective sphere which is restricted in rolling by the groove slides down slowly without rolling. Due to the speed difference at this time, a difference X occurs in the flight distance between the good sphere and the defective sphere.

An experiment was conducted to examine the distance difference X. It is described below.

The experiment was carried out by applying a vibration to a shooter having a rolling surface length L of 100 mm with a vibrator, pouring a sphere into a V-groove of the shooter, and rolling down the ball. The selection target is an alloy ball for bonding electronic components manufactured by the atomizing method. The alloy sphere rolled out when the inclination angle θ of the shooter 1 was about 1 to 2 degrees, and when the inclination angle was the same, the rolling speed at the tip of the shooter was almost equal, and all the true spheres drawn a parabola and fell to the apogee. On the other hand, the defective ball (W ball) slipped at a considerably slower speed than the true ball and fell to a perigee. At this time, the inclination angle θ and the drop height H = 100 mm
Table 1 shows the relationship of the flight distance difference X at the following conditions.

[0022]

[Table 1] Particle size 100 μm, 200 μm, 300 μm, 760 μm
When the same experiment was performed for each of the alloy balls, the obtained data did not differ much from those shown in Table 1.

When the inclination angle was 35 ° or more, the rolling speed and the sliding speed of the sphere were almost the same, and the flight distance was hardly different.

According to this experiment, the inclination angle θ of the shooter is 1 to
It has been found that the most stable sorting can be performed at about 30 degrees, especially about 5 degrees ± 1 degree. Also, it was considered that the rolling surface of the shooter preferably had a surface roughness similar to that of the polished surface. Regarding the material of the rolling surface, the same result was obtained with any of plastic, aluminum, and stainless steel, and it was also found that the effect was not significantly related. It seems that there is no problem if the hardness of the rolling surface is HRC30 or more.

FIG. 5 is an enlarged cross section of the V groove 5. In a general V-groove in which two surfaces intersect at an acute angle, in the case of a W-ball having the shape shown in the figure, it is conceivable that the attached microsphere SB may pass through the gap at the bottom of the groove and roll normally. As shown in FIG. 5, when the groove bottom of the V groove 5 is formed with an arc surface or a flat surface and the groove bottom approaches the surface of the sphere B, the microsphere SB hits the groove bottom. Slide down without fail.

FIG. 8 shows an example in which lands 12 between adjacent V grooves are inclined in the land width direction. As shown
When the surface of the land 12 descends toward the V groove 5, the sphere always flows into the V groove even if the land 12 is wide.

FIG. 9 shows a shooter formed of a commercially available L-shaped angle material. The shooter 1 may be the one described above, or may be a member in which a plurality of members having one vertical groove are closely arranged side by side and fixed integrally.

The apparatus of the present invention can be used for selecting a sphere smaller than the alloy sphere used in the experiment. Further, it can also be used for sorting defective bearing balls or the like in which chipping or the like has occurred, and the sorting object is not limited to spheres obtained by the atomizing method.

[0029]

As described above, in the sorting apparatus of the present invention, the sphere is given directionality by the vertical groove provided in the shooter, so that the true sphere rolls down at a high speed and the defective ball such as a W ball is formed. The sphere slides down at a slow speed. In this way, a difference is produced in the flight distance between the two spheres, and the defective spheres are selected by using the difference in the flight distance, so that W balls of small spheres and the like that could not be sorted by a sieve sorter or a roller sorter can be reliably used. And can be used to reduce the rejection rate and improve the reliability of products using the selected spheres.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing an embodiment of a sorting device of the present invention.

FIG. 2 is a perspective view showing a main part of the above device.

FIG. 3 is an explanatory diagram of a sorting principle.

FIG. 4 is a front view of the shooter of FIG. 3;

FIG. 5 is an enlarged sectional view of a V-groove.

FIG. 6 is a view showing a preferred shape of a V-groove.

FIG. 7 is a view showing another preferred shape of a V-groove.

FIG. 8 is a diagram showing an example in which lands between V grooves are inclined.

FIG. 9 is a front view of a shooter formed of an angle material.

FIG. 10 is a diagram showing a main form of a W ball.

FIG. 11 is a diagram showing the principle of a conventional tilt selection method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shooter 2 Sorting plate 3 Vibrator 5 V groove 6 Enclosure wall 10, 11 Collection box 12 Land

Claims (6)

[Claims] 1. A shooter inclined downward before a sphere to be sorted is placed and rolled down, a good sphere that normally rolls down on the shooter and falls in a parabola in front of the shooter and slides down on the shooter A sorting plate for disposing and sorting the defective spheres falling near the chute between the falling points of the two spheres, and providing a vertical groove into which the sphere enters the chute so as to give directionality to the sphere moving by the vertical groove. Sphere sorting device. 2. The ball sorting device according to claim 1, further comprising a vibrator for vibrating the shooter. 3. The groove according to claim 1, wherein the vertical groove is a V-groove, and the groove bottom of the V-groove is formed as an arcuate surface or a flat surface to reduce the distance from the surface of the sphere flowing into the groove to the groove bottom. An apparatus for sorting spheres as described. 4. The apparatus according to claim 1, wherein a plurality of said vertical grooves are provided in parallel.
4. The sphere selecting device according to any one of claims 1 to 3. 5. The sphere sorting device according to claim 4, wherein a land is provided between the adjacent vertical grooves, and the land is inclined so as to descend toward the vertical groove. 6. The sphere sorting apparatus according to claim 1, wherein the inclination angle of the shooter is 1 degree or more and 30 degrees or less.