JP3568178B2 - Resistance welding equipment - Google Patents

Description

[0001]
[Industrial applications]
TECHNICAL FIELD The present invention relates to a welding device suitable for joining or resistance-welding dissimilar metal materials or general similar metal materials.
[0002]
[Prior art]
Generally, in the welding process of a metallic material, when a welding current flows through an object to be welded, heat is generated due to contact resistance or the like, and the heat causes the metallic material to melt or soften and solidify, thereby performing welding or joining. It is something to be done.
[0003]
However, since the joining of dissimilar metals is diffusion joining due to the softening of metal materials having different softening temperatures, thermal conductivities, and thermal expansion coefficients, the desired welding quality is generally lower than that of similar metals such as iron. It is very difficult to get. In particular, it is difficult to perform diffusion bonding between a copper member and an iron member having the above-mentioned characteristics that are relatively different from each other.
[0004]
In a method of joining a copper workpiece and an iron workpiece, which is currently widely used, first, a welding auxiliary member made of the same metal material as the iron workpiece, that is, iron, is prepared in advance. The iron-made welding auxiliary member has a shape suitable for the copper workpiece, and in a state where the iron-welding auxiliary member is combined with the copper workpiece, the combined portion is brazed over 360 degrees. , And are integrated with the brazing material. Next, the iron welding auxiliary member integrated with the copper workpiece and the iron workpiece are welded by ordinary resistance welding. In this case, since resistance welding is performed between iron materials, welding can be easily performed under normal welding conditions.
[0005]
[Problems to be solved by the invention]
However, as is apparent from the above, in the case of the conventional joining method, an intermediate member such as a welding auxiliary member made of the same metal material as one of the workpieces must be prepared in advance, and such a joining method is required. Since the materials of the welding auxiliary member and the other workpiece are naturally different, there is a drawback that an operation for brazing them is required.
[0006]
Also, in resistance welding that hermetically seals a case and cap made of the same general metal material such as iron for electronic components, dust is generated inside the hermetic seal during welding, especially in the case of small electronic components. Causes a problem that the characteristics of electronic elements such as a semiconductor, a surface acoustic wave device, and a crystal housed therein are adversely affected. In addition, Chile is disliked because it has various adverse effects.
[0007]
According to the present invention, in order to solve such a conventional problem, in order to perform a preferable diffusion bonding of different metal materials or a similar conductive metal material, a welding current is applied to these materials in a short time. Based on the finding that it is preferable to inject, we propose a structure that improves the response speed of the upper welding electrode to sinking due to expansion and softening of the work piece during welding, and welding current between different metals or in a short time It is a first object of the present invention to provide a resistance welding apparatus that can flow between well-conductive metals to perform good diffusion bonding.
[0008]
In addition, by improving the response speed of the upper welding electrode to the sinking caused by expansion and melting of the metal material when welding an object such as a case and a cap of an electronic component made of the same normal metal material such as iron, The second purpose is to suppress or prevent the occurrence of dust at the time.
[0009]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a supporting mechanism, a movable block coupled to a distal end of the pressing mechanism so as to be able to move up and down with respect to the supporting mechanism when the pressing mechanism operates, One end is fixed to the distal end portion, the pressing auxiliary member having a high elastic force in response to the movement of the pressing mechanism, a plurality of guide shafts implanted in the movable block, and free along the guide shaft. A plurality of linear driving members, a supporting member fixed to the linear driving member and capable of moving up and down with a small external force, supported by the supporting member, and fixed to a lower end of the pressure assisting member. A resistance welding apparatus including an upper welding electrode and a lower welding electrode that cooperates with the upper welding electrode to join or weld a workpiece.
[0010]
In order to solve the above-described problem, a second invention includes a support mechanism, a movable block held by the support mechanism so that the support mechanism can move up and down with respect to the support mechanism when the pressing mechanism operates, and A pressurizing auxiliary member capable of transmitting the movement of the pressurizing mechanism to the upper welding electrode at a high speed, an intermediate connecting member fixed to a portion where the level is not affected by expansion and contraction of the pressing auxiliary member, and the upper welding electrode; A first flexible conductive member that electrically connects between the intermediate metal member and a second flexible conductive member that electrically connects the intermediate metal member to one end of a secondary winding of the welding transformer; An object of the present invention is to provide a resistance welding apparatus comprising: a lower welding electrode for joining or welding an object to be welded in cooperation with an upper welding electrode.
[0011]
In order to solve the above-mentioned problem, a third invention is the invention according to claim 2, wherein the first flexible conductive member and the second flexible conductive member are each formed by laminating a plurality of thin metal plates, An object of the present invention is to provide a resistance welding apparatus characterized in that the thin metal plate of the first flexible conductive member is thinner than the thin metal plate of the second flexible conductive member.
[0012]
In order to solve the above-mentioned problem, a fourth invention is the invention according to claim 2, wherein the first flexible conductive member and the second flexible conductive member are each formed by laminating a plurality of thin metal plates, The first flexible conductive member is provided with a resistance welding apparatus characterized in that it is thinner and wider than the second flexible conductive member.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. First, in FIG. 1, reference numeral 1 denotes a floor or a base on which the resistance welding apparatus is installed, 2 denotes a supporting mechanism fixed to the floor or the base 1, 3 denotes a pressing mechanism including a cylinder device, and 4 denotes a pressing mechanism 3 A movable block made of a metal material connected to the tip end, 5 is a pressing auxiliary member such as a spring or an electromagnetic pressing device, 6 is directly or indirectly connected to the lower end of the pressing auxiliary member 5, A support member 7 made of a metal material such as copper, which also acts as an upper welding electrode supported on the support member 6, is shown in detail in FIG. 2 showing the upper welding head.
[0014]
Further, reference numeral 8 denotes a lower welding electrode disposed at a position facing the upper welding electrode 7, and reference numeral 9 denotes a level which is not affected by expansion and contraction of the pressure assisting member 5, that is, welding to the movable block 4 at a height. The L-shaped intermediate connecting member 10 fixed by the first flexible conductive member which easily connects between the support member 6 and the L-shaped intermediate connecting member 9 and the L-shaped intermediate connecting member 9 is connected to the L-shaped intermediate connecting member 9. It is a conductor that connects between the power supply conductor 12 and a second flexible conductive member that is longer than the first flexible conductive member 10.
[0015]
The first flexible conductive member 10 is formed by laminating a sufficiently thin copper plate having a thickness of, for example, about 0.03 mm so as to be easily bent, while the second flexible conductive member 11 is formed of the first flexible conductive member 10. It is formed by laminating thin copper plates having a thickness of, for example, about 0.1 mm, which is thicker than the copper plate used for (1). Further, if necessary, the thickness of the first flexible conductive member 10 is reduced to facilitate bending of the first flexible conductive member 10 as compared with the second flexible conductive member 11, and the width is increased accordingly. It is sufficient to correspond to the current capacity. Further, in order to increase the substantial width of the first flexible conductive member 10, the first flexible conductive member 10 may be divided into two or more and used in parallel. With such a configuration, the maximum effect can be obtained while limiting the cost increase.
[0016]
Reference numeral 13 denotes the other power supply conductor connected to the lower welding electrode 8, and reference numeral 14 denotes a secondary winding N2 connected to the power supply conductors 12 and 13, and a primary winding N1 magnetically coupled thereto. It is a welding transformer having. The primary winding N1 of the welding transformer 14 is connected to a power pulse supply circuit including an energy storage capacitor (not shown). In the case of diffusion bonding of different kinds of metal materials, a pulse of 7 milliseconds or less is preferable. A power pulse having a small width is selectively supplied from a power pulse supply circuit.
[0017]
As shown in FIG. 2, the movable block 4 coupled to the distal end portion of the pressing mechanism 3 by a mounting member 3a has a part of a pressing auxiliary member 5 such as a spring having one end fixed to the mounting member 3a. It has a central hole 4a that extends. Two guide shafts 4A are implanted in the movable block 4 at positions opposite to each other with respect to the center hole 4a. Each of the two guide shafts 4A is provided with a linear drive member 4B such as a linear motion bearing. The linear drive member 4B can freely move the guide shaft 4A with a very small external force.
[0018]
The support member 6 is fixed to the linear drive member 4B on both sides, and is supported by the guide shaft 4A via the linear drive member 4B. The support member 6 supports the upper welding electrode 7 at substantially the center thereof, and the upper welding electrode 7 is directly fixed to the lower end of the pressure assisting member 5. However, in FIG. 2, illustration of the L-shaped intermediate connection member 9 and the first and second flexible conductive members 10 and 11 is omitted.
[0019]
Therefore, according to this structure, the upper welding electrode 7 is supported by the supporting member 6 which can move up and down in the vertical direction with a small external force, and at the same time, is connected to the pressurizing auxiliary member 5 which can provide a highly responsive elastic force. Therefore, the upper welding electrode 7 is capable of responding to a subtle change in the distance between the upper welding electrode 7 and the lower welding electrode 8.
[0020]
Next, the diffusion bonding operation by this device will be described. First, the upper welding electrode 7 clamps a first workpiece (not shown) made of a copper material or the like. When the pressing mechanism 3 operates and moves downward, the upper welding head including the movable block 4, the guide shaft 4A, the linear driving member 4B, the pressing auxiliary member 5, the supporting member 6, and the upper welding electrode 7 is accordingly generated. The whole descends. On the other hand, although not shown, a second workpiece made of an iron material or the like is set on the lower welding electrode 8, and the first workpiece clamped to the upper welding electrode 7 is attached to the lower welding electrode 8. Is brought into contact with the second workpiece to be supported. The upper welding electrode 7, the supporting member 6, and the linear driving member 4B stop at that position, but as the pressing mechanism 3 further moves down, the pressing auxiliary member 5 is contracted, and the metal block 4, the guide shaft 4A and The linear drive member 4B descends together with the pressing mechanism 3.
[0021]
Further, as the movable block 4 moves down, the second flexible conductive member 11 bends greatly, and the first flexible conductive member 10 moves together with the movable block 4 and the support member 6, so that the first flexible conductive member 10 moves down in the initial state. As described above, when the support member 6 stops and the movable block 4 descends while contracting the pressurizing auxiliary member 5, the movable block 4 slightly deforms from the initial state. However, as described above, the first flexible conductive member 10 is made to be more flexible than the second flexible conductive member 11, so that a single flexible conductor corresponding to the second flexible conductive member 11 serves as a power supply conductor. The adverse effect on the movement between the support member 6 and the upper welding electrode 7 is reduced as compared with the conventional case where the connection between the support member 6 and the support member 6 is performed. Therefore, the responsiveness of the upper welding electrode 7 is improved.
[0022]
When the pressurizing mechanism 3 is pressurizing, the gap between the metal block 4 and the support member 6 becomes smaller after the upper welding electrode 7 and the like are stopped, and the pressurizing auxiliary member 5 stores downward mechanical energy. Also, they act to absorb upward forces above a certain level. In this way, the pressing auxiliary member 5 contracts while the pressing mechanism 3 operates and performs the downward movement, and the pressure between the upper welding electrode 7 and the lower welding electrode 8 reaches a predetermined level. Then, a pulse-like welding current having a short pulse width is supplied to the upper welding electrode 7 and the lower welding electrode 8 from the welding transformer 14 and the power supply conductors 12 and 13.
[0023]
When a pulse welding current having a short pulse width is applied in a state where a pressure is applied at a predetermined pressure, the copper material and the iron material in the welded portions of the first and second workpieces are softened. As the joint between the two dissimilar metal materials starts to soften, for example, when the pressure assisting member 5 is a spring, the expansion of the joint at the initial stage of welding is instantaneously absorbed by the pressure assisting member 5, and the pressing force is reduced. In the working state, the pressurizing auxiliary member 5 always applies a pressing force to the joining portion. Therefore, it is necessary to apply a pressing force which has an extremely fast response to sinking due to softening of the metal material due to the progress of diffusion bonding. Can be.
[0024]
As the response speed of the auxiliary pressurizing member 5 increases, the pulse welding current having a shorter pulse width, that is, the current energy can be concentrated in a short time, and can flow between the dissimilar metals to be welded. Can be softened to a desirable state, so that satisfactory diffusion bonding can be achieved. One means that does not lower the response speed of the pressurizing auxiliary member 5 than the conventional one is the first flexible member 10 which is easily bent, and the other means is the pressurizing auxiliary member 5 and the linear driving member 4B.
[0025]
In the above embodiments, the joining of dissimilar metal materials or the same kind of highly conductive metal materials has been described. This resistance welding apparatus is very effective in improving welding quality because it can apply pressurization with an extremely fast response to sinking due to melting of the material. In particular, this resistance welding apparatus is suitable for hermetic sealing of electronic components and the like because it can suppress or prevent the generation of dust that tends to occur during welding.
[0026]
【The invention's effect】
As described above, according to the present invention, the structure for enhancing the responsiveness of the upper welding electrode is provided, so that the welding current is allowed to flow between the dissimilar metals or between the good heat conductive metals in a short time to achieve good diffusion bonding. A possible resistance welding apparatus can be provided.
[0027]
Furthermore, according to the present invention, it is possible to suppress or prevent the generation of dust that tends to occur when welding common metal materials of the same kind, so that not only can the welding quality be improved, The practical effect is very large, for example, it is possible to prevent adverse effects on various members or elements inside the object.
[Brief description of the drawings]
FIG. 1 is a view for explaining an embodiment of a resistance welding apparatus according to the present invention.
FIG. 2 is a view for explaining an embodiment of the resistance welding apparatus of the present invention.
[Explanation of symbols]
1 floor or base 2 support mechanism 3 pressure mechanism 4 movable block 4A guide shaft 4B implanted in movable block 4 movable block Linear drive member 5 engaged with 4 ... Pressure assisting member 6 ... Support member 7 ... Electrode for upper welding 8 ... Electrode for lower welding 9 ... Intermediate connection Body 10 first flexible conductive member 11 second flexible conductive member 12, 13 power supply conductor 14 welding transformer

Claims (4)

A support mechanism;
A movable block coupled to the distal end of the pressurizing mechanism so as to be able to move up and down with respect to the support mechanism when the pressurizing mechanism operates;
A pressure assisting member having one end fixed to a distal end of the pressure mechanism and having a high elastic force in response to the movement of the pressure mechanism;
A plurality of guide shafts planted on the movable block;
A plurality of linear drive members movable freely along the guide shaft;
A support member fixed to the linear drive member and capable of moving up and down with a slight external force ;
It is supported by the support member, and the upper welding electrode which is fixed to the lower end of the pressure auxiliary member;
And the lower welding electrode for joining or welding the welding subject to electrode cooperates for the upper welding;
A resistance welding apparatus comprising: A support mechanism;
A movable block held by the support mechanism so as to be able to move up and down with respect to the support mechanism when the pressing mechanism operates;
A pressure assisting member capable of transmitting the movement of the pressure mechanism to the upper welding electrode at a high speed;
An intermediate connecting member fixed to a portion whose level is not affected by expansion and contraction of the pressure assisting member;
A first flexible conductive member for electrically connecting the intermediate metal member and the upper welding electrode;
A second flexible conductive member for electrically connecting the intermediate metal member to one end of a secondary winding of the welding transformer;
A lower welding electrode for joining or welding the workpiece in cooperation with the upper welding electrode;
A resistance welding apparatus comprising: In claim 2,
The first flexible conductive member and the second flexible conductive member are each formed by laminating a plurality of thin metal plates, and the thin metal plate of the first flexible conductive member is formed of a thin metal plate of the second flexible conductive member. A resistance welding apparatus characterized by being thinner than a plate. In claim 2,
The first flexible conductive member and the second flexible conductive member are each formed by laminating a plurality of thin metal plates, and the first flexible conductive member is thinner than the second flexible conductive member, and Resistance welding equipment characterized by its wide width.

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