JP2511860B2 - Pressing force adjusting device - Google Patents

Abstract

PURPOSE:To change and adjust a pushing force to an article on a holding tool, by making the energizing force of a first spring to act on the article holding tool, which is independently suspended by a first spring by utilizing the position of the holding tool. CONSTITUTION:In a sucking and holding, an arm 11 is started to descend and supporting by a first lever 32 is released. Then, a collet shaft 28 is lowered by a first spring 30, and a head part 29 is contacted to a second lever 38, which faces a head part 29 at the position directly beneath the part 29. The second lever 28 is energized by a second spring 41 so as to push up the collet shaft 28. The shaft 28 is supported by the second lever 38 at the position the shaft 28 is lowered by an interval B, where the lowering force and the lifting force are balanced. At this time, the second spring 41 is deflected by the distance corresponding to the difference (B-A) between the interval B and an initial interval A. The force is stored in this way. The magnitude of the force can be set at a desired value by the manipulation of a micrometer head 42.

Description

Description: TECHNICAL FIELD The present invention relates to a pressing force adjusting device technology, and more particularly to a technology for changing a pressing force at the time of sucking and holding an object to be bonded and a pressing force at the time of bonding, for example, The present invention relates to a technique effectively used in a bonding device for bonding a hemispherical dome-shaped pellet to a stem in manufacturing an infrared light emitting diode.

[Background technology]

In the manufacture of infrared light emitting diode, as a device for bonding a hemispherical dome-shaped pellet to the stem,
After sucking and holding the pellets placed on the supply stage with a collet, transfer the bonding stage where the stem is positioned, and in the bonding stage,
There is a structure in which a pellet adsorbed and held by a collet is pressed against a stem and thermocompression bonded.

In such bonding, there is a problem that pellets may be damaged or defective bonding may occur unless the pressing force when the pellet is sucked and held by the collet and the pressing force when the pellet is bonded to the stem by the collet are changed. It was revealed by the present inventor that

An example that describes pellet bonding technology is "Introduction to automatic assembly of electronic components" issued by Nikkan Kogyo Shimbun.
There are P69-P76, issued on July 30, 1981.

[Object of the Invention]

An object of the present invention is to provide a pressing force adjustment technique that can change and adjust the pressing force.

The above and other objects and novel features of the present invention are as follows.
It will be apparent from the description of this specification and the accompanying drawings.

[Outline of Invention]

The outline of a typical invention among the inventions disclosed in the present application will be briefly described as follows.

A structure in which the biasing force of the second spring is applied to the article holder independently suspended by the first spring depending on the position of the holder so that the pressing force of the holder against the article is changed and adjusted. Is.

[Embodiment 1] FIG. 1 is an enlarged vertical sectional view showing a pressing force adjusting device according to an embodiment of the present invention, FIG. 2 is a plan view taken along line II-II of FIG. 1, and FIG. FIG. 4 is a schematic front view showing the bonding apparatus in which it is used, FIG. 5 is an exploded perspective view showing an infrared light emitting diode, and FIG. 6 is an assembly perspective view of the same. is there.

In the present embodiment, in the manufacturing of an infrared light emitting diode, the bonding apparatus aligns the hemispherical dome-shaped pellet 1 as the pressed object on the stem 2 and the pattern 1a formed on the half-divided surface to the stem side pattern 2a. The pellet 1
And a bonding stage 5 on which the stem 2 is positioned are installed on the bed 3 at positions separated from each other. A pellet mounting plate 6 formed of a transparent material such as glass is horizontally installed on the supply stage 4. A television camera (hereinafter referred to as a camera) 7 serving as a first visual device is installed on the bed 3 so as to face upward just below the mounting plate 6.
The camera 7 is configured to recognize the pattern 1a of the pellet 1 placed on the placing plate 6.

A heat block 8 is installed on the bed 3 on the bonding stage 5, and the heat block 8 is configured to heat the stem 2 placed on the upper surface thereof. The second camera 9 is located directly above the bonding stage 5.
Is installed downward, and the second camera 9 is configured to recognize the pattern 2a of the stem 2 placed on the heat block 8.

An XY table 10 is provided on the left side of the bonding stage 5, and the XY table 10 is configured to move an arm 11 supported on the upper surface in the XY direction so as to project rightward. The arm 11 is arranged substantially horizontally on the XY table 10, and the left end portion thereof is pivotally mounted by a pin 12 so as to rotate in the vertical direction, and is a vertical movement device including a servomotor and a cam mechanism. It is configured to be moved up and down by 13. At the right end of the arm 11, a pressing force adjusting device 15 having a collet 14 as a holder for sucking and holding the pellet 1 is installed, as shown in FIG.

The first and second cameras 7 and 9 have a controller including an image processing unit and a central processing unit such as a computer.
16 are connected, and a monitor 17 is connected to the controller 16. Controller 16 is based on the image from each camera XY table 10, arm up-and-down movement device 13,
It is configured to control a servo motor or the like on the arm described later.

The pressing force adjusting device 15 shown in FIG.
The sleeve 21 is vertically arranged at the right end of the arm 11 as the main body of the pressing force adjusting device, and is rotatably supported by the bearing 22 in the horizontal plane. A driven sprocket is attached to the outer periphery of the lower end of the sleeve 21.
23 is fitted, and a belt 24 made of rubber or the like is wound around the sprocket 23. The belt 24 is wound around a driving sprocket 25 which is rotationally driven by a servo motor 26 installed at an appropriate position on the arm 11, so that the sleeve 21 is attached to the servo motor 26.
It is designed to be turned by 26.

A collet shaft 28 is inserted in the sleeve 21 in a vertical direction with its axis aligned, and is supported by a plurality of bearing rollers 27 so as to be movable up and down in a non-rotatable state. A first spring 29, which is a compression coil spring, is interposed between and so as to constantly urge the collet shaft 28 downward. Collet shaft
The collet 14 is attached to the lower end of the 28, and the head portion 29 is integrally provided on the upper end so as to project.

A first bracket 31 is erected near the right end of the arm 11, and a first lever 32 formed in a substantially L shape is pivotally mounted on the pin 33 at an intermediate part of the upper end of the first bracket 31. It is mounted such that it can be worn and rotated in a vertical plane. A rod 34 is pivotally attached to one end of the first lever 32 by a pin 35, and the rod 34 is linked to the arm up-and-down device 13 and serves as a pressing force switching device 36 (fourth force switching device).
(See the figure). The pressing force switching device 36 includes a ring mechanism, a cam mechanism, etc., and is configured to move the rod 34 to the right during bonding. The second lever 32 is arranged so as to receive the lower surface of the head portion 29 of the collet shaft 28 at the other end thereof, so that the collet shaft 28 can normally support its load.

A second bracket 37 is erected on the right side of the first bracket 31 in the arm 11, and a second lever 38 formed in a substantially L shape is arranged downward at the upper end of the second bracket 37. The intermediate portion thereof is pivotally attached to the pin 39 so as to be rotatable in the vertical direction. The lower end of the second lever 38 is urged by the second spring 41 so as to be pressed against the stopper 40 on the arm 11.
Reference numeral 41 is composed of a compression coil spring or the like and applies a reaction force to the first bracket 31 via a micrometer head 42 as an urging force adjusting device. The micrometer head 42 is configured to adjust the urging force by changing and adjusting the effective length of the second spring 41. Second lever
The lower end 38 of the collet shaft 28 is arranged so that the upper end thereof faces directly below the lower surface of the head portion 29 of the collet shaft 28 with a predetermined distance A, while the lower end is restricted by the stopper 40. When the distance A falls below A, the second
The elastic force of the spring 41 is urged.

 Next, the operation will be described.

When the pellets 1 are supplied downward onto the mounting plate 6, the pattern 1a of the pellets 1 is transferred to the first camera 7 via the mounting plate 6.
Is transmitted through and the electric signal is transmitted to the image processing unit of the controller 16. The image processing unit displays the image of the pellet pattern 1a on the monitor 17 and transmits the image signal to the central processing unit of the controller 16.

The central processing unit of the controller 16 collates the image position of the pellet 1 with a preset reference position and obtains an error between the two positions. Then, the controller 16 controls the servo motor 26 on the XY table 10 and the arm 11 so as to eliminate the error and adjusts the XY and θ directions of the collet 14 to execute the alignment between the collet 14 and the pellet 1. Let That is, the servo motor 26
When is rotated, the sleeve 21 is swung via the sprockets 25 and 23 and the belt 24, so that the collet shaft 28, which is stopped by the bearing roller 27, is co-rotated with the sleeve 21, and as a result, the collet 14 is rotated. The θ direction of the adsorbed and held pellet 1 is adjusted.

With the alignment operation between the collet 14 and the pellet 1, the arm 11 is lowered by the vertical movement device 13,
14 is pressed against the hemispherical surface of the pellet 1 with a predetermined pressing force described later, and the pellet 1 is adsorbed and held by the collet 14.

When the collet 14 holds the pellet 1 by suction, the arm 11
Is lifted by the vertical movement device 13 and the XY table
The pellet 1 which is moved to the left by 10 and is held by the collet 14 is transferred to the reference position on the bonding stage 5.

On the other hand, the stem 2 of the diode is supplied to the heat block 8 by a suitable feeder (not shown) to be positioned and heated. The pattern 2a of the positioned stem 2 is photographed by the second camera 9, and an electric signal is transmitted to the image processing unit of the controller 16. The image signal processed by the image processing unit is transmitted to the central processing unit of the controller 16.

The controller 16 displays the image of the stem 2 on the monitor 17, and collates a preset reference position with the image position of the stem to obtain an error between the two positions.
Then, the controller 16 eliminates the error.
The collet 14 is moved in the same manner as described above for fine alignment, and the collet 14 is pressed against the stem 2 with a predetermined pressing force as will be described later. At this time, since the stem 2 is heated by the heat block 8, the pellet 1 is thermocompression-bonded to the stem 2. After the bonding is completed, the suction holding of the collet 14 is released, and the collet 14 is returned to the reference position on the supply stage 4.

Thereafter, by repeating the above operation, the pellets are properly aligned with the stem and sequentially bonded.

By the way, in the above operation, when the pellet 1 is suction-held by the collet 14, the pressing force against the pellet 1 is preferably small, and when the pellet 1 is bonded to the stem 2 by the collet 14, the pressing force is preferably larger.

Therefore, in the present embodiment, the pressing force adjusting device 15 suspends the collet shaft 28 independently, and the pressing force at the time of suction holding and bonding is adjusted by the following action.

When the arm 11 starts descending during suction holding,
Since the pressing force switching device 36 operates to move the rod 34 to the right, the first lever 32 moves away from the lower surface of the head portion 29 and the collet shaft.
Release 28 support. When the support by the first lever 32 is released, the collet shaft 28 is pushed down by the first spring 30, so that the lower surface of the head portion 29 is pressed against the second lever 38 which is directly below. Since the second lever 38 is biased by the second spring 41 so as to push up the collet shaft 28, the collet shaft 28 is supported by the second lever 38 at a position lowered by an interval B at which the pushing-down force and the pushing-up force are balanced. It will be in the state to be. At this time, the second spring 41 flexes by an amount corresponding to the difference (BA) between the distance B and the initial distance A to store the force. Incidentally, the magnitude of this accumulated force can be set to a desired value by operating the micrometer head 42.

When the collet 14 comes into contact with the pellet 1 as the arm 11 descends, the collet shaft 28 is guided in the sleeve 21 by the roller 27 so as to follow the subsequent lowering of the arm 11, and the force is balanced. While breaking through, the first spring 30
It bends and rises relatively. At this time, since the second spring 41 is bent by the distance difference (BA), the bending of the first spring 30 causes the collet shaft 28 to move.
The second spring 41 cancels out the elastic force that urges against the rise of the. Therefore, the rising line of the pressing force of the collet shaft 28 against the pellet 1 based on the elastic force of the first spring 30 has a gentle inclination as shown by the broken line C in FIG. Then, the controller 16 controls the suction means (not shown) of the collet 14 so that the pellet 1 is suction-held under the pressing force P ₁ or less.

Next, at the time of bonding, the pellet 1 sucked and held by the collet 14 as the arm 11 descends is transferred to the stem 2
The collet shaft 28 ascends in the sleeve 21 so as to follow the subsequent lowering of the arm 11. Then, the bonding is performed at a stroke S ₂ which is slightly larger than the stroke S ₁ of the collet shaft 28 at the time of the suction holding and the pressing force becomes P ₂ as shown in FIG. Further, the controller 16 controls the arm up-and-down moving device 13 and the like.

That is, the solid line D in FIG. 3 indicates the first spring 30.
The pressing force rising line in the case of only the above is shown, and this rising line D is steeper than the offset rising line C. Since the pressing force P ₂ at the time of bonding is on this steep slope rising line D, the pressing force P ₂ at the time of bonding is attracted and held without advancing the collet shaft 28, that is, the arm 11 greatly. It can be set to be sufficiently larger than the pressing force P _{1 of} . That is, the increasing rate P ₂ / P ₁ of both pressing forces is sufficiently larger than the increasing rate S ₂ / S ₁ of stroke.

[Embodiment 2] FIG. 7 is an enlarged vertical sectional view showing another embodiment of the present invention.

The second embodiment is different from the first embodiment in that the second spring 40A is configured to act in the direction of increasing the pressing force during bonding.

That is, at the time of bonding, when the arm 11 starts descending, the rod 34 is moved to the right, so that the first lever 32A releases the support of the second lever 38A. By this release, the second lever 38A is pulled by the second spring 40A and engages with the upper surface of the collar portion 29A of the collet 28, and the second spring 41A.
The pulling force is applied downward to the collet shaft 28. As a result, the pressing force of the collet shaft 28 at the time of bonding is increased.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Nor.

For example, the urging force control means is not limited to use the configuration in which the urging force control means is linked to the arm up-and-down movement device, but may be configured to operate the electromagnetic plunger mechanism or the like by the controller.

The holder is not limited to the collet, and the structure for moving the holder, the pellet supply stage, the bonding stage, and the like are not limited to those in the above embodiment.

〔effect〕

(1) The pressing force of the holder with respect to the article is changed and adjusted by making the biasing force of the second spring act on the article holder that is independently suspended by the first spring depending on the position of the holder. Therefore, the article can be handled with a pressing force according to the desire.

(2) Since the load on the article can be reduced by setting the pressing force at the time when the article is sucked and held by the holder to reduce the load on the article, damage to the article or the like can be prevented.

(3) By setting a large pressing force for crimping the article with the holder, the crimping can be ensured, so that the quality and reliability of the product can be improved.

[Field of application]

In the above description, the invention mainly made by the present inventor has been described as applied to a bonding device for bonding the pellet of the infrared light emitting diode to the stem, which is the field of application of the invention, but is not limited thereto. In the manufacturing of electronic devices such as transistors and semiconductor devices, it can also be applied to a bonding device for bonding pellets on a substrate. At least, the present invention exerts an excellent effect when applied to the case where it is desirable to change and adjust the pressing force.

[Brief description of drawings]

FIG. 1 is an enlarged vertical sectional view showing a pressing force adjusting device which is an embodiment of the present invention, FIG. 2 is a plan view taken along the line II-II of FIG. 1, and FIG. 3 is for explaining its action. FIG. 4, FIG. 4 is a schematic front view showing the bonding in which it is used, FIG. 5 is an exploded perspective view showing an infrared light emitting diode, FIG. 6 is the same perspective assembly view, and FIG. It is an expanded longitudinal cross-sectional view showing another embodiment of. 1 ... Pellet (object to be pressed), 2 ... Stem (object to be bonded), 3 ... Base, 4 ... Supply stage, 5 ...
... Bonding stage, 6 ... Pellet mounting plate, 7 ...
... 1st camera (1st visual device), 8 ... Heat block, 9 ... 2nd camera (2nd visual device), 10 ... XY table, 11 ... Arm, 12 ... Pin, 13 ... Arm Vertical movement device, 14 …… collet (holding device), 15 …… bonding device, 16 …… controller, 17 …… monitor, 21 …… sleeve, 22 …… bearing, 23 …… driven sprocket, 24 …… belt, 25 …… Motor sprocket, 26 …… Servo motor,
27 …… Bearing roller, 28 …… Collet shaft, 29 …… Head part, 29A …… Flange part, 30,30A …… First spring, 31 ……
First bracket, 32, 32A ... First lever, 33 ... Pin, 34 ... Rod, 35 ... Pin, 36 ... Pressing force switching device (urging force control means), 37 ... Second bracket, 38 , 38A
...... Second lever, 39 ...... pin, 40 ...... stopper, 41, 41
A …… Second spring, 42 …… Dial gauge head (biasing force adjusting device).

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Karasawa 300, Hisasho Nakai-cho, Ashigaragami-gun, Kanagawa Hitachi Electronics Engineering Co., Ltd. (72) Shingo Ibe 300 Hisakata, Nakai-cho, Ashigarakami-gun, Kanagawa Hitachi Electronic Engineering Co., Ltd. In-company (56) References JP-A-60-178637 (JP, A)

Claims (5)

(57) [Claims] 1. A holder for holding an article, a main body for slidably supporting the holder within a predetermined stroke range, a first spring for urging the holder in one direction, and a holder separately from the first spring. A pressing force adjusting device comprising: a second spring for urging the tool; and a urging force control means for causing the urging force of the second spring to act on the holder depending on the position of the holder with respect to the main body. 2. The pressing force adjustment according to claim 1, wherein the second spring is configured to bias the holder in a direction that cancels the biasing force of the first spring. apparatus. 3. The pressing force device according to claim 1, wherein the second spring is configured to urge the holder in a direction to increase the urging force of the first spring. . 4. The urging force control means is configured to detect the position of the holder and to apply the urging force of the second spring at a predetermined position.
The pressing force adjusting device described in the paragraph. 5. The pressing force adjusting device according to claim 1, wherein the holder is rotatably supported.