JPH11291053A - Seam welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform a superior seam welding by a small electric current, even for an increased welding speed, by reducing impact and a pressurizing force when the roller electrode comes into contact with the lid. SOLUTION: An electrode holder 16 is attached, freely vertically movably through a guide 25, to the guide bar 13 of a guide mechanism 11. In addition, a roller electrode 8 is attached to the electrode holder 16 and brought into press-contact with a stopper 27 by a spring 26. When the roller electrode 8 is brought into contact with the lid 5 at the time of seam welding, a load imparted to the lid 5 is only the force from the roller electrode 8, the electrode holder 16 and from the spring 26, and no load is added from the guide bar 13 and the attaching part 22 of the guide mechanism 11, etc., thereby enabling the reduction of the impact against the lid 5 and the pressurizing force from the roller electrode 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seam welding apparatus for automatically seam-joining a metal lid to an opening of a package containing a chip such as a semiconductor element and a quartz oscillator.

[0002]

2. Description of the Related Art A seam welding apparatus hermetically seals semiconductor circuit elements such as semiconductor integrated circuits, transistors and light emitting diodes and chips such as crystal oscillators to a container body by a micro parallel seam joining method (hereinafter simply referred to as seam joining method). (For example, Japanese Patent Publication No. 1-38737).
JP-A-58-197859, JP-A-9-197845
No. 3000078).

[0003] This seam joining apparatus is shown in Figs.
As shown in FIGS. 1A and 1B, a ceramic (or entirely made of metal) package 3 in which a metal sealing frame 2 is brazed on a ceramic substrate 1 is provided with a chip such as a quartz oscillator or a semiconductor element. After storing the chip 4 and electrically connecting the chip 4 and a lead (not shown) with a wire,
Metal lid (lid) made of Kovar, 42 alloy, etc.
5 covers the opening of the package 3 and is temporarily fixed by spot welding. Next, the package 3 to which the lid 5 is temporarily fixed is conveyed to the seam area, and a pair of tapered roller electrodes 8 are applied to the lid 5 at a constant pressing force, for example, at one end edge A on two long sides of the lid 5. And the roller 3 is energized while moving the package 3 together with the carrier board 9 in the direction of arrow A at a constant speed (for example, 8 V, 140 to 180).
A) Then, the two sides on the long side are melted by Joule heat generated at this time, and are seam-joined to the sealing frame 2. When the seam joining of the two long sides is completed, the roller electrode 8 is once raised to adjust the electrode interval, and the carrier board 9 is rotated 90 ° in a horizontal plane as shown in FIG. The roller 3 is lowered again, and the other two opposite sides of the lid 5, that is, the two short sides are similarly seam-bonded, whereby the package 3 is hermetically sealed.

The electrode lifting and lowering device 7 for raising and lowering the roller electrode 8 includes a guide mechanism 11 and an air cylinder 12 as a driving device for raising and lowering the guide mechanism 11. The guide mechanism 11 includes two guide bars 1 that can be moved up and down.
3, a guide 14 for holding these guide bars 13 so as to be able to move up and down, and a roller 15 and an electrode holding portion 16 respectively attached to the upper and lower ends of each guide bar 13. The electrode holder 16 is provided with the guide bar 1.
3 and a bearing member 19 attached to the block 18 for rotatably supporting the roller electrode 8, and a guide mechanism 11 applied to the roller electrode 8.
And a spring 20 for reducing the load on the electrode holder 16.
Urged upwards.

The air cylinder 12 includes a movable rod 12
A is provided with a lifting member 17 attached to the tip end of the guide bar 13.
I support.

[0006]

In the conventional seam welding apparatus described above, since the load of the guide bar 13 is directly applied to the roller electrode 8, the impact when the roller electrode 8 is brought into contact with the lid 5 is large, and No. 5 has a problem that it is easy to cause a displacement. In this case, when the spring force of the spring 20 is increased, the impact can be reduced. However, when the spring electrode 20 is too large, the roller electrode 8 jumps up when it comes into contact with the lid 5, and not only does the time required to obtain a stable contact state increase. However, it is not preferable because it is necessary to increase the driving force for raising and lowering the guide bar 13. When the pressing force of the roller electrode 8 on the lid 5 increases due to the load of the guide mechanism 11 and the electrode holding portion 16, the lid 5
The contact resistance between the roller and the roller electrode 8 is reduced, so that a sufficient amount of heat cannot be obtained, and good seam bonding cannot be obtained.
Therefore, it is necessary to supply a large current. However, if a large current is supplied to the roller electrode 8, it is difficult to control burning and joining of the lid 5, and there is a problem that the speed of seam joining cannot be increased.

Therefore, as a method for solving such a problem, for example, a seam welding apparatus disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 9-300788 has been proposed. In this seam welding apparatus, a holding mechanism for reducing a pressing force of a roller electrode to a lid to be smaller than a load of an electrode portion is provided in an electrode holding portion for holding an electrode portion. As the holding mechanism, an elastic member or a balancer is used.In the case of the elastic member, the elastic member is mounted between the electrode holding portion and the electrode portion, and in the case of the balancer, the roller is centered on the swing fulcrum of the arm holding the electrode portion. It is provided at a position facing the electrode.

However, even in such a conventional seam welding apparatus, since the weight of the electrode section itself is not reduced as in the conventional apparatus shown in FIG. 2, the inertia when the electrode section is raised and lowered is large. Therefore, there is a problem that the problem that the impact when the roller electrode 8 is brought into contact with the lid 5 is large cannot be solved.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. It is an object of the present invention to reduce the impact and pressure when a roller electrode comes into contact with a lid, and to reduce the joining speed. It is an object of the present invention to provide a seam welding apparatus capable of performing a good seam joining with a small current even if the height is increased.

[0010]

According to a first aspect of the present invention, a metal lid is placed in an opening of a package containing a chip, and two opposing sides of the lid are paired with each other. In a seam welding apparatus for simultaneously seam-joining the package by a roller electrode,
A guide mechanism having a plurality of guide bars, a driving device for simultaneously raising and lowering each of the guide bars, and an electrode holding portion attached to each of the guide bars so as to be vertically movable,
The invention is characterized in that the roller electrode is attached to the electrode holder.

According to a second aspect, in the first aspect,
An elastic member for urging the electrode holding portion downward is provided.

[0012] In a third aspect based on the second aspect,
The guide mechanism is provided with a stopper in which the electrode holding portion is pressed against the elastic member.

In the first aspect, since the roller electrode is attached to the guide bar so as to be movable up and down, the guide bar does not become a load on the roller electrode, and the inertia of the electrode portion can be reduced. Therefore, the impact and pressure when the roller electrode contacts the lid are small. In the second aspect, since the elastic member urges the electrode holding portion downward, when the roller electrode comes into contact with the lid, the spring does not easily jump up, and stable contact can be obtained quickly. In the third invention, the stopper locks the electrode holding portion at the lower limit position.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 is a schematic sectional view showing an embodiment of the seam welding apparatus according to the present invention.
In the drawings, the same components as those described in the section of the related art are denoted by the same reference numerals, and description thereof will be omitted as appropriate. In FIG. 1, the seam welding apparatus according to the present invention includes a guide mechanism 11, a driving device 21 for moving the guide mechanism 11 up and down, an electrode holding section 16 attached to the guide mechanism 11 so as to be able to move up and down, Part 16
And the roller electrode 8 and the electrode holding unit 16 constitute an electrode unit.

The guide mechanism 11 includes two vertical guide bars 13 of the same shape, guides 14 for holding the respective guide bars 13 so as to be able to move up and down, and rollers mounted on the upper ends of the respective guide bars 13. 15 and a horizontal mounting portion 22 for connecting the lower ends of both guide bars 13, and each of the guide bars 13 holds the electrode portion so as to be movable up and down.

A drive motor is used as the drive device 21. A disk-shaped eccentric cam 24 is attached to an output shaft 23 of the drive device 21.
When the guide bars 13 are moved up and down in parallel, the guide bars 13 are simultaneously moved up and down at a constant speed. Here, in the present embodiment, an example is shown in which a drive motor is used as the drive device 21, but an air cylinder 12 may be used as in the conventional device shown in FIG. Further, the roller 15 is not limited to the guide bar 13 side, but may be a member attached to the elevating member 17 side. Further, a pin may be used instead of the roller 15, or the guide bar 13 may be directly fixed to the elevating member 17.

The electrode holder 16 is provided with the guide bar 1.
The block 3 is provided with a block 18 mounted on the block 18 so as to be able to move up and down via a guide member 25, a bearing member 19 mounted on the block 18, and a spring 26 for urging the electrode holding portion 16 downward. The spring 26 comprises a tension coil spring,
One end is locked to the mounting portion 22 and the other end is locked to the block 18 to press the block 18 against a stopper 27 provided on the upper surface of the mounting portion 22. The spring 26 has a relatively low spring force and is adjusted by an appropriate adjusting means in accordance with the load on the electrode portion.
As the guides 14 and 25, commercially available LM guides having a plurality of balls are used. The roller electrode 8 is rotatably mounted on the bearing member 19 via a shaft 28, and is connected to a power supply by a power supply cable (not shown).

In the seam welding apparatus having such a structure, when the lid 5 is joined to the sealing frame 2, the guide bar 13 of the guide mechanism 11 is lowered by the driving device 21, and each roller electrode 8 is connected to the lid 5. Touch the edge. At this time, since the load applied to the lid 5 is such that the electrode holding portion 16 is mounted on the guide bar 13 so as to be able to move up and down, the load on the guide bar 13, the mounting portion 22, the stopper 27, etc. is not applied to the roller electrode 8. Electrode holder 1
6 and the spring force of the spring 26 only. Therefore, the inertia of the electrode portion at the time of lifting and lowering is small, and the impact on the lid 5 and the pressing force of the roller electrode 8 are smaller than those of the conventional device shown in FIG. The spring 22 is connected to the electrode holder 16.
Is biased in the direction of gravity, so that when the roller electrode 8 comes into contact with the lid 5, the jump-up is small, and stable contact with the lid 5 can be obtained quickly. Guide bar 1
Reference numeral 3 indicates that after the roller electrode 8 comes into contact with the lid 5, the roller electrode 8 further lowers by a certain amount and stops, and the block 18 is separated from the stopper 27 against the spring 26. In this state, the roller electrode 8
When the package 3 is moved together with the carrier board 9 at a constant speed in a direction perpendicular to the paper surface, the lid 5 is melted by Joule heat and is seam-joined to the sealing frame 2.

As described above, in the present invention, the electrode portion including the roller electrode 8 and the electrode holding portion 16 is connected to the guide bar 13.
When the roller electrode 8 is brought into contact with the lid 5, the guide bar 13 and the mounting portion 2
2. The impact when the roller electrode 8 comes into contact with the lid 5 can be reduced without the load of the stopper 27 or the like being applied to the lid 5. Therefore, the temporarily fixed lid 5 does not shift, and if the load on the lid 5 is small, the contact resistance between the lid 5 and the roller electrode 8 can be reduced. Can be seamed.

In the above-described embodiment, the example in which the tension coil spring 26 is used as the elastic member for urging the electrode holding portion 16 downward has been described. Synthetic resin or the like. In the above-described embodiment, the lid 5 is spot-welded.
Is applied to a seam welding apparatus used for seam joining. However, the present invention is not limited to this, and the lid 5 can be used in the same manner when the lid 5 is temporarily fixed by spot welding.

[0021]

As described above, according to the seam welding apparatus of the present invention, the load applied to the lid when the roller electrode is brought into contact with the lid can be reduced. The pressing force can be reduced. Therefore, there is no displacement of the lid, and if the pressing force is small, the contact resistance between the lid and the roller electrode increases. can do. Further, since the electrode holding portion is urged downward by the elastic member, stable contact between the roller electrode and the lid can be quickly obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a seam welding apparatus according to the present invention.

FIG. 2 is a schematic sectional view showing a conventional example of a seam welding apparatus.

FIGS. 3A and 3B are views for explaining a seam joining method.

[Explanation of symbols]

1 ... substrate, 2 ... sealing frame, 3 ... package,
4 ... chip, 5 ... lid, 8 ... roller electrode, 9 ... carrier board, 11 ... guide mechanism, 12 ... air cylinder, 1
3 ... guide bar, 14 ... guide, 16 ... holding part, 18 ...
Block, 19: bearing member, 20: spring, 21: drive motor, 22: holding part, 25: guide, 26: spring, 27
... stopper.

Claims (3)

[Claims] 1. A seam welding apparatus in which a metal lid is placed in an opening of a package containing a chip and two opposite sides of the lid are simultaneously seam-bonded to the package by a pair of roller electrodes. A guide mechanism having two guide bars, a drive device for simultaneously moving the guide bars up and down, and an electrode holding portion attached to each of the guide bars so as to be movable up and down. A seam welding device having electrodes mounted thereon. 2. The seam welding apparatus according to claim 1, further comprising an elastic member for urging the electrode holding portion downward. 3. The seam welding apparatus according to claim 2, wherein a stopper is provided on the guide mechanism so that the electrode holding portion is pressed against the elastic member.