JP3766653B2 - Semi-insulator welding method and welding apparatus therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for directly welding a semi-insulator having a metal (film) surface coated with a chemical film (coating film) and a metal conductor, and a welding apparatus therefor.
[0002]
[Prior art]
Conventionally, since it has been difficult to weld the semi-insulator and the metal conductor, the metal conductor 32 is placed on the semi-insulator 31 as shown in FIG. Is pushed from the solid line as shown by a two-dot chain line to form a skewered shape, the metal conductor 32 is partially penetrated through the semi-insulator 31, and the burr (projection piece) 34 is projected downward. 11 (b), pressing with a press machine as indicated by arrows 35 and 36 to crush the downwardly projecting burr 34 to form a retaining portion 37, so that the inside of the semi-insulator 31 A method of integrating the metal film and the metal conductor 32 was used.
[0003]
However, the mechanical coupling as shown in FIG. 11 has a drawback that the conduction performance varies and a quality problem is likely to occur, or that two machining steps are necessary and inefficiency.
[0004]
Therefore, as shown in FIG. 10, a hole 40 is once formed in the semi-insulator 31 having the electrically insulating coating layer (chemical film) 38 and the metal film 39, and the other metal conductor 32 has a small size. There is a technique in which the projection 41 is formed by a center punch, and the small projection 41 is engaged with the hole 40, sandwiched between the welding electrodes 42 and 43, and a current is applied in a pressurized state to perform spot (resistance) welding. It has been proposed (see, for example, Patent Document 1).
[0005]
[Patent Document 1]
JP-A-5-154667 (FIG. 1 and claim 1)
[0006]
[Problems to be solved by the invention]
However, the conventional welding method as shown in FIG. 10 requires labor for forming the hole 40 in machining, and also requires labor for forming the small protrusion 41 by press working, and the work efficiency is high. It was extremely bad.
[0007]
The present invention provides a method and apparatus for directly welding a semi-insulator and a metal conductor in an efficient manner, stably and with high quality, by solving such conventional problems. For the purpose.
[0008]
[Means for Solving the Problems]
In view of this, the present invention provides a high voltage method for locally breaking the chemical film by pressing a semi-insulator whose metal surface is coated with a chemical film and a metal conductor with a pair of welding electrodes. one pulse is applied, then 0.2 after m sec ~ 1.0 m sec minute downtime on by applying a high voltage second pulses for the welding, and welding the conductors to the semi-insulating material, further, the The area of the current in the graph showing the time change of the current flowing through the welding electrode is set to be larger in the second pulse than in the first pulse, and the voltage is higher than that in the first pulse. In this method, the two pulses are set smaller .
Also, the welding apparatus according to the present invention, the pair of welding electrodes, chemical conversion to generate a high voltage first pulses to break the chemical conversion film of the semi-insulator conversion film on the metal surface is coated locally A first pulse generating circuit for film local destruction, and a second pulse generating circuit for main welding for generating a high-voltage second pulse for main welding after a minute rest time after the generation of the first pulse , In the first pulse generation circuit and the second pulse generation circuit, the area of the current in the graph showing the time change of the current flowing through the welding electrode is larger in the second pulse than in the first pulse. The voltage is set larger in the second pulse than in the first pulse , and the first pulse generating circuit further includes a first step-up transformer that boosts the alternating current from the alternating current power supply. The current boosted by the first step-up transformer is converted to direct current A rectifier for conversion has an oil capacitor for storing electrical energy, and the second pulse generation circuit, a second step-up transformer for boosting the AC from the AC power source, boosted by the second step-up transformer having a rectifier for converting currents into direct current, an oil capacitor or electrolytic capacitor for storing electrical energy, a.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on the illustrated embodiment.
3, FIG. 4, FIG. 5 and FIG. 6 show an embodiment showing the spot (resistance) welding method according to the present invention in the order of steps. First, as shown in FIG. Then, pressure A is applied across the semi-insulator 3 and the metal conductor 4.
[0010]
The semi-insulator 3 is composed of a metal layer (thin plate) 5 such as Al, Cu or Fe, and insulating films (coating films or plating films) 6 and 7 laminated (coated) on both surfaces thereof. . The metal conductor 4 is made of Al, Cu, Fe, or the like.
As a specific example, the semi-insulator 3 is an aluminum (Al) foil having a chemical film formed on the surface, or an oxide film (defined as a kind of chemical film formation in the present invention) is formed on the surface. Al foil. The metal conductor 4 corresponds to a lead wire (end portion thereof).
[0011]
In the pressurized state, as shown in FIGS. 4 to 5, a high voltage first pulse P ₁ for locally breaking the chemical film 6 is applied. That is, as shown in FIG. 5, one chemical film 6--the chemical film 6 on the side on which the metal conductor 4 is pressed is locally broken.
[0012]
Next, a high voltage second pulse P ₂ for main welding is applied after a minute rest time T ₃ , and the metal conductor 4 is welded to the semi-insulator 3 as shown in FIG. As the minute pause time T _3, 0.2msec ~ 1.0msec is desirable. If it is less than the lower limit, it is close to the state where it is applied at once, and there are large variations in welding quality and strength (not stable). Furthermore, it becomes difficult to produce an electric (electronic) circuit for generating the second pulse P ₂ with a minute pause time T ₃ less than the lower limit. On the other hand, when the upper limit is exceeded, the destroyed portion of the chemical film 6 heated by the first pulse P ₁ has cooled down, and sufficient welding strength and stability can be achieved by the second pulse P ₂ . However, it becomes difficult to obtain.
In addition, in FIG. 6 (or FIG. 5), the case where the (the other) chemical film 7 that contacts the lower electrode 2 side is not torn, but depending on the welding conditions, it may be torn, It may be broken like that.
[0013]
FIGS. 1 and 2 are graphs in which the voltage V and current I of the first pulse P ₁ and the second pulse P ₂ described above are indicated by a broken line and a solid line, respectively. The horizontal axis represents time, and the vertical axis represents time. Indicates the values of voltage V and current I. FIG. 1 shows the waveforms of the first pulse P ₁ and the second pulse P ₂ that are suitable when the chemical films 6 and 7 are thin and FIG. 2 is relatively thick.
[0014]
Comparing the two figures, the voltage V ₁ , current I _1, and time T ₁ of the first pulse P ₁ are substantially equal (or the latter is set slightly larger), but in the second pulse P ₂ , the latter of area S ₂ ─── current I ₂ × T ₂ ─── current I ₂ is set larger than the former, the latter be a thick chemical conversion film 6 and 7 provide more heat energy It is set so that it can be welded sufficiently. However, the values of the current I ₂ and the voltage V ₂ are set so that the latter is set to a lower value so as to achieve beautiful and uniform welding.
[0015]
In each of FIGS. 1 and 2, it is desirable to set so that the following relational expression is established.
0.2 msec ≤ T ₃ ≤ 1.0 msec
S ₂ > S ₁
100 volts ≤ V ₂ <V ₁ ≤ 1500 volts
T ₂ > T ₁
[0016]
From the above equation, the first pulse P ₁ (as compared to the second pulse P ₂ ) is a pulse having a high voltage V ₁ and a very short time T ₁ , and the chemical film 6 (or chemical films 6 and 7) is localized. You can see that In addition, the second pulse P ₂ indicates that the main welding is performed at a sufficiently large current time S ₂ (compared to the first pulse P ₁ ). Further, in conventional welding, a low voltage of 6 to 8 volts has been frequently used, but in the present invention, a voltage of 100 to 1500 volts is referred to as “high voltage” in the present invention. ── is given.
[0017]
FIG. 12 shows a comparative example, in which the semi-insulator 3 is pressed between the electrodes ₁ and ₂ and the above-mentioned high voltage is applied once --- the current area obtained by combining S ₁ and S ₂ once-- When applied to, it indicates that explosion Y occurs as shown in FIG. Moreover, even if such a blow-off Y is prevented, it has been found that the setting of the welding conditions is extremely difficult, and the welding strength and quality are not stable.
[0018]
As described above with reference to FIGS. 1 to 6, the present invention provides a high voltage for locally breaking the chemical film (insulating film) 6 or chemical films (insulating films) 6 and 7. The first pulse P ₁ is first applied, and then after a minute rest time T ₃ of 0.2 msec to 1.0 msec, a high voltage second pulse P ₂ for main welding is applied, and the metal conductor 4 is This is a method of (spot) welding to the semi-insulator 3, which can reliably prevent the explosion Y as in the comparative example of FIG. 12, and can maintain the quality such as the welding strength stably and constantly. Moreover, it has the advantage of easy control of the welding conditions.
[0019]
Next, FIG. 7 to FIG. 9 show an electric circuit of a welding apparatus used for performing the above-described welding.
Reference numeral 8 denotes a first step-up transformer, to which an alternating current from an alternating current power source 9 is connected via a first charging switching element 10. The current boosted by the first step-up transformer 8 is converted into direct current by the first rectifier 11, and is passed through the first discharge switching element 12, the first inductance L ₁ , and the first capacitors C ₁ . Connect (wiring) to the electrodes 1 and 2. A first pulse charge control unit 15 controls the first charge switching element 10. Reference numeral 16 denotes a first pulse discharge controller, which controls the first discharge switching element 12. A charge / discharge timing control unit 17 outputs a signal to the first pulse charge control unit 15 and the first pulse discharge control unit 16 to control charging / discharging timing.
[0020]
Reference numeral 18 denotes a second step-up transformer, to which an alternating current from the alternating current power source 9 is connected via a second charging switching element 20. The current boosted by the second step-up transformer 18 is converted into a direct current by the second rectifier 21, and is passed through the second discharge switching element 22, the second inductance L ₂ , and the second capacitor C ₂ . Connect (wiring) to the electrodes 1 and 2. A second pulse charge control unit 25 controls the second charge switching element 20. A second pulse discharge control unit 26 controls the second discharge switching element 22. The charge / discharge timing control signal from the charge / discharge timing control unit 17 includes the second pulse charge control unit 25 and the second pulse discharge control in addition to the first pulse charge control unit 15 and the first pulse discharge control unit 16 described above. The unit 26 is also connected to be sent.
[0021]
The first pulse generation circuit 27 for local film formation local destruction for generating a high voltage first pulse P ₁ that locally breaks the chemical film formation 6 (and 7) on the pair of welding electrodes 1 and 2 is shown in FIG. , A first charge switching element 10, a first step-up transformer 8, a first rectifier 11, a first pulse charge control unit 15, a charge / discharge timing control unit 17, a first capacitor C ₁ . The first discharge switching element 12, the first inductance L ₁ , the first pulse discharge control unit 16 and the like are included. An oil capacitor is suitable as the first capacitor C ₁ that stores electrical energy.
[0022]
A second pulse generating circuit 28 for main welding for generating a high voltage second pulse P ₂ for main welding after a minute pause time T ₃ after the generation of the first pulse P ₁ is shown in FIG. The second charge switching element 20, the second step-up transformer 18, the second rectifier 21, the second pulse charge control unit 25, the charge / discharge timing control unit 17, the second capacitor C ₂ . The second discharge switching element 22, the second inductance L ₂ , the second pulse discharge control unit 26, and the like are included.
[0023]
In FIG. 7, the charge / discharge timing control unit 17 is commonly used for the first pulse generation circuit 27 and the second pulse generation circuit 28. However, it may be provided separately (not shown). ).
An oil capacitor or an electrolytic capacitor is suitable as the second capacitor C ₂ in which the second pulse generating circuit 28 accumulates electric energy.
[0024]
In FIG. 7, the start signal S ₀ is sent to the charge / discharge timing control unit 17, and as shown in FIGS. 1 and 2, first, the first pulse P ₁ and then a predetermined minute pause time T _{3 are obtained.} After the second pulse P ₂ is applied.
FIG. 8 shows the current flow at the moment when the first pulse P ₁ is applied to the electrodes 1 and 2 by the arrow I ₁ . FIG. 9 shows the current flow at the moment when the second pulse P ₂ is applied by an arrow I ₂ .
[0025]
By the first inductance L ₁ and the first capacitor C ₁ , the waveform of the first pulse P ₁ —particularly the pulse width (time T ₁ ) —can be increased or decreased.
The second inductance L ₂ and the second capacitor C ₂ can be used to increase or decrease the waveform of the second pulse P ₂ , especially the pulse width (time T ₂ ).
Further, in the illustrated example (FIGS. 7 to 9), the ON times of the discharge switching elements 12 and 22 are controlled by the discharge control units 16 and 26 to further increase / decrease the pulse widths of the pulses P ₁ and P ₂ .
3 to 6, the method and the apparatus of the present invention can be applied to the semi-insulator 3 having no bottom surface chemical conversion film 7.
[0026]
【The invention's effect】
The present invention has the following remarkable effects by the above-described configuration.
(According to claim 1) The semi-insulator 3 having the metal surface coated with the chemical film 6, 7 and the metal conductor 4 do not cause a problem such as explosion (see FIG. 12). It is possible to always weld with a stable welding strength, and an excellent quality product can be obtained easily and efficiently.
That is, the conventional mechanical processing as shown in FIG. 10 and FIG. 11 can be omitted, and stable welding can be realized easily and quickly electrically.
Further, it is possible to realize more stable and excellent welding to the semi-insulator 3.
In addition, there is no that there is a small pause time T ₃ is too small. That is, no explosion occurs and it is difficult to create an electric circuit.
In addition, there is no that there is a small pause time T ₃ is too large. That is, the destroyed portion of the chemical film 6 heated by the first pulse P ₁ is not cooled by the application of the second pulse P ₂ , and sufficient welding strength and stability are obtained. Can do.
Further, the first pulse P ₁ can be easily broken locally as a pulse having a high voltage V ₁ and a short time compared to the second pulse P ₂ .
Further, the second pulse P ₁ gives a large amount of heat energy and can be sufficiently welded even if the thick film 6 or 7 is formed.
[0027]
(According to claim 2 ) The semi-insulator 3 having the metal surfaces 6 and 7 coated on the metal surface and the metal conductor 4 are produced without causing problems such as explosion Y (see FIG. 12). It is possible to always weld with a stable welding strength, and an excellent quality product can be obtained easily and efficiently.
That is, the conventional mechanical processing as shown in FIG. 10 and FIG. 11 can be omitted, and stable welding can be realized easily and quickly electrically.
In addition, it is possible to realize discharge in an extremely short time as illustrated in FIG. 1 or FIG. 2 and to easily perform high-precision control.
Further, the first pulse P ₁ can be easily broken locally as a pulse having a high voltage V ₁ and a short time compared to the second pulse P ₂ .
Further, the second pulse P ₁ gives a large amount of heat energy and can be sufficiently welded even if the thick film 6 or 7 is formed.
[Brief description of the drawings]
FIG. 1 is a graph showing temporal changes in welding current and welding voltage for explaining the present invention.
FIG. 2 is a graph showing another example of a temporal change in welding current and welding voltage for explaining the present invention.
FIG. 3 is an explanatory diagram of a first step of welding.
FIG. 4 is an explanatory diagram of a second step of welding.
FIG. 5 is an explanatory diagram of a third step of welding.
FIG. 6 is an explanatory diagram of a fourth step of welding.
FIG. 7 is a circuit diagram showing an embodiment of a welding apparatus according to the present invention.
FIG. 8 is an explanatory diagram when a first pulse is generated.
FIG. 9 is an explanatory diagram when a second pulse is generated.
FIG. 10 is an explanatory diagram showing a conventional example.
FIG. 11 is an explanatory diagram showing another conventional example.
FIG. 12 is an explanatory diagram showing a comparative example.
[Explanation of symbols]
1 electrode 2 electrode 3 semi-insulator 4 metal conductor 6 chemical film formation
27 First pulse generator
28 Second pulse generation circuit C ₁ first capacitor C ₂ second capacitor P ₁ first pulse P ₂ second pulse T ₃ minute pause time
8 First step-up transformer
18 Second step-up transformer

Claims (2)

A semi-insulator whose metal surface is coated with a chemical film and a metal conductor are pressed with a pair of welding electrodes, and a high voltage first pulse for locally breaking the chemical film is applied, Next, 0.2 m sec ~ after 1.0 m sec minute downtime by applying a high voltage second pulses for the welding, and welding the conductors to the semi-insulating material,
Further, the area of the current in the graph showing the time change of the current flowing through the welding electrode is set to be larger in the second pulse than in the first pulse, and the voltage is larger than that in the first pulse. The method for welding a semi-insulator, wherein the second pulse is set smaller . A pair of welding electrodes, and the chemical conversion film first pulse generating circuit for local disruption for generating a high voltage first pulses to break locally the chemical conversion film of the semi-insulator conversion film on the metal surface coated A second pulse generation circuit for main welding for generating a high-voltage second pulse for main welding after a minute pause time after the generation of the first pulse ,
In the first pulse generation circuit and the second pulse generation circuit, the area of the current in the graph showing the time change of the current flowing through the welding electrode is larger in the second pulse than in the first pulse. And the voltage is set smaller in the second pulse than in the first pulse,
Further, the first pulse generation circuit includes a first step-up transformer that steps up alternating current from an AC power source, a rectifier that converts current boosted by the first step-up transformer into direct current, and oil that stores electrical energy. A capacitor, and
A second step-up transformer that boosts alternating current from the alternating-current power source; a rectifier that converts a current boosted by the second step-up transformer into direct current; and an oil capacitor that stores electrical energy. Or an electrolytic capacitor .

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