JPH01133690A - Ultrasonic welding method for metal wire bar body - Google Patents

Abstract

PURPOSE:To inspect an ultrasonic welding state of all products under nondestruction during ultrasonic welding work by detecting variation of the ultrasonic welding state during the ultrasonic welding work of a metal wire bar body to a welding mating metal body. CONSTITUTION:The metal wire bar body 6 to be welded is superposed on the welding mating metal body 7 and arranged on a working bench 1. These are then pressed by a pressing mechanism 8 such as a hydraulic cylinder via an ultrasonic vibration transmitter 5. Further, ultrasonic vibrations from an ultrasonic oscillator 3 and an ultrasonic vibrator 4 are given to the metal wire bar body 6 and the welding mating metal body 7 via the ultrasonic vibration transmitter 5 to perform ultrasonic welding. During this ultrasonic work, the variation of a load current of the aforementioned ultrasonic oscillator 3 is detected by a detector 9. From this variation, the ultrasonic welding state is decided by a deciding device 10 and outputted to a recorder 11 such as a printer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for ultrasonic welding of a metal filament for ultrasonically welding a metal filament to a metal body to be welded.

[Prior art] A metal wire body consisting of a metal wire (including stranded wire), a solid rod, a strip of rectangular material, a tube such as a vibrator, and a welding partner metal such as a metal wire body or a metal molded product. Ultrasonic welding with a body uses ultrasonic vibrations to rub the mutual contact surfaces of the metal filament and the metal body to be welded, destroying the oxide film on the surfaces of both, and smoothing the surfaces of both. Welding is performed by plastic deformation, and in general, as shown in Figure 6, the welding strength is controlled by the deformation m, and the welding strength increases as the amount of deformation increases. It is known that the body strength decreases and, in the worst case, the metal filament is broken.If the amount of deformation is small, the metal filament strength is high, but the welding strength is low and peeling occurs at the welded part. Further, the welding strength varies depending on the shape of the metal filament, the amplitude of the ultrasonic vibration, the pressing force, the working time, the presence or absence of inclusions in the welded part, etc.

In this way, in ultrasonic welding, the W3 bonding strength varies depending on various welding conditions, so it is necessary to inspect the welding strength.

[Problems to be Solved by the Invention] Conventionally, ultrasonic welding strength has been tested using a tensile test, which has the problem of damaging the product and rendering it unusable. For this reason, it was impossible to inspect all products. In addition, inspection had to be carried out in a separate process, which led to problems with poor work efficiency.

An object of the present invention is to provide a method for ultrasonic welding of metal filaments, which allows inspection of the entire product without destroying the product during the ultrasonic welding operation.

Means for Solving the Problems] To explain in detail the present invention to achieve the above object, the present invention is an ultrasonic welding method for ultrasonically welding a metal filament to a metal body to be welded using an ultrasonic welding machine. In the welding method, during the ultrasonic welding operation of the metal filament and the welding partner metal body, detecting the amount of change that changes in the ultrasonic welding state of the metal filament and the welding partner metal body, The method is characterized in that the state of ultrasonic welding is determined based on the amount of change.

[Function] In this way, the amount of change that changes in the state of ultrasonic welding between the metal wire and the metal object to be welded (for example, the amount of change in the height of the welded part, the amount of load current of the ultrasonic welding machine, the amount of load current) By detecting the moving average value, power factor, amount of deformation strain, etc.) and determining the state of ultrasonic welding based on the amount of change, it is possible to perform non-destructive inspection during ultrasonic welding work, and moreover, it is possible to inspect all products. It can be performed.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. In the figure, 1 is a workbench, 2 is a body frame, 3 is an ultrasonic oscillator supported by the body frame 2, 4 is an ultrasonic vibrator that is excited by the ultrasonic oscillator 3 and vibrates, and 5 is an ultrasonic vibrator 4 Ultrasonic imaging transducers 6 and 7 are arranged between the ultrasonic vibration transducer 5 and the workbench 1, and are a metal wire body to be ultrasonically welded and a metal body to be welded. be. In this embodiment, a twisted core wire is used as the metal filament 6,
A bus bar is used as the metal body 7 to be welded. ,
8 is a pressure mechanism such as a hydraulic cylinder that is supported by the fuselage frame 2 and pressurizes the metal filament 6 and the metal body 7 to be welded via the ultrasonic imaging transmitter 5; 9 is a load current from the ultrasonic oscillator 3; A change amount detector such as a load current analyzer that detects 10
11 is a determiner which determines the state of ultrasonic welding by inputting the amount of change in the load current output from the amount of change detector 9;
is a recorder such as a printer that records the determination result of the determiner 10.

Therefore, in this embodiment, while applying pressure to the superposed metal wire body 6 and the welding partner metal body 7 using the pressure mechanism 8, a pulse-like input (the pulse width is set so that optimum welding can be achieved) is applied to the ultrasonic oscillator 3. ), and the ultrasound imaging of the ultrasound transducer 4 obtained at this time is transmitted to the ultrasound vibration transmitter 5.
is applied to the metal filament 6 and the metal body 7 to be welded together through the ultrasonic welding process. During this ultrasonic welding work, the change amount detector 9 detects the load current within a predetermined time (0.3 sec in the example) from the start of ultrasonic welding of the ultrasonic oscillator 3 (Q, 1 sec in the example). do. This means that when ultrasonic welding is started, the metal filament 6 and the welding partner metal body 7 are separated within a predetermined time from the start.
Focusing on the fact that the frictional resistance between the The change amount detector 9 detects the change amount depending on the state. If the time period during which the load current is applied is too long, the metal filament 6 may be cut or the frictional resistance may decrease again due to heat, resulting in defective products or making judgment impossible, which is not preferable. do not have. According to experiments, when the ultrasonic welding state is insufficient, the load current A within a predetermined time from the start of ultrasonic welding becomes lower than the load current lower limit set value A1, as shown in Figure 3, and the ultrasonic welding state is insufficient. It has been found that when the load current is sufficient, the load current is located between the load current lower limit setting value A1 and the load current upper limit setting value A2 as shown in FIG.

Note that B indicates the amount of distortion at this time. Therefore, in this embodiment, the load current lower limit setting value A1 and the load current upper limit setting value 1M1Az are preset in the determiner 10 for each time, and the change amount detector 9 outputs the ultrasonic welding start time. The load current of these set values A1. Enter between A2. The determiner 11 determines whether or not 1. If yes, the welded part
If it is not included, record it as a welding failure and record it as @11.

FIG. 2 shows a second embodiment of the invention. Note that the same parts as in FIG. 1 are indicated by the same reference numerals.

In the figure, 12 is a light emitting part that emits laser light toward the surface of the metal filament 6, and 13 is a light emission part that receives the laser beam on the opposite side of the light emitting part 12 with the metal filament 6 in between. .

The amount of distortion (sinking amount) of the metal filament 6 and the welding partner metal body 7, which is an output signal from the light emitting part 13, is detected by the change amount detector 9 as a change m that changes in the ultrasonic welding state. It has become.

In the case of this embodiment, when ultrasonic welding is started, the amount of strain (sinking amount) between the metal filament 6 and the metal body 7 to be welded increases within a predetermined time from the start of ultrasonic welding. A predetermined period of time (in the example, 0
．． The amount of strain within 4 seconds to 0.7 seconds is detected by the change amount detector 9 as the amount of change that changes in the ultrasonic welding state. According to experiments, the strain f! within a predetermined time after the start of ultrasonic welding. When the ultrasonic welding condition is insufficient, kB becomes lower than the strain amount lower limit set value B1 as shown in FIG. It was found that the distortion amount is located between B1 and the lower limit set value B2. For this reason, in this embodiment, the strain amount upper limit setting value B1 and the strain amount upper limit setting value B2 are preset in the determiner 10 for each time, and the ultrasonic welding starts which is output from the change amount detector 9. The amount of distortion within the subsequent predetermined time is set to these set values B1.
The determining device 11 determines whether the welding temperature falls between B2 or not, and if it does, it is recorded as a welding step, and if it does not, it is recorded as a welding defect.

In addition, other variables that change in the ultrasonic welding state include the moving average value of the load current within a predetermined time from the start of ultrasonic welding, the power factor, etc., and these can also be used to make a determination. can.

. Further, as a method of determination, determination may be made at each of a plurality of specific times during which the load current is applied with an optimal time width, and a comprehensive determination may be made from the results of each determination.

Furthermore, if the judgment results in FIGS. 1 and 2 are used and a comprehensive judgment is made by ANDing them, more accurate judgment can be made.

[Effects of the Invention] As explained above, in the method for ultrasonic welding of metal filaments according to the present invention, changes in the ultrasonic welding state between the metal filament and the metal body to be welded are detected and Since the state of ultrasonic welding between the metal filament and the metal object to be welded is determined based on the amount of change, non-destructive inspection can be performed during ultrasonic welding work, and all products can be inspected. , it is possible to significantly improve product reliability.

[Brief explanation of the drawing]

FIGS. 1 and 2 show the first embodiment of the present invention. A front view showing each configuration of the ultrasonic welding apparatus of the second embodiment, FIGS. 3 to 5 are waveform diagrams showing the principle of determination of the present invention, and FIG. FIG. 3 is a diagram showing the relationship between strength and deformation with respect to a metal body to be welded. DESCRIPTION OF SYMBOLS 1... Workbench, 2... Airframe frame, 3... Ultrasonic oscillator, 4... Ultrasonic vibrator, 5... Ultrasonic vibration transmitter, 6... Metal filament, 7... Welding partner metal body, 8... Pressure mechanism, 9... Change amount detector, 10...
- Judgment device, 11... Recording device. Figure 1 Figure 3'' □Time opening (set)
a, r Figure 5 @ Figure 6 Also, the written amendment of the procedure for determining the amount of compensation (August 25, 1988, Director General of the Japan Patent Office, Yoshi 1) Moon Takeshi 1, Indication of the case, Patent Application No. 62-293196 2, Invention Name: Ultrasonic welding method for metal filaments 3, relationship with the amended case Patent applicant (529) Furukawa Electric Co., Ltd. 4, agent: Shin 14-31-6, Minato-ku, Tokyo Details of the 6th floor of the expenditure building In Column 6 of the Detailed Description of the Invention of the Book, page 4, line 17 of the Specification of Contents of the Amendment, "Rataru., 8 wa" is corrected to "Rataru. 8 wa". That’s all for now ゝh7〕：ゝ、

Claims (1)

[Claims] In an ultrasonic welding method in which a metal filament is ultrasonically welded to a welding partner metal body using an ultrasonic welding machine, the metal filament is A method for ultrasonic welding of metal filaments, characterized in that the amount of change in the state of ultrasonic welding between the metal body and the metal body to be welded is detected, and the state of ultrasonic welding is determined based on the amount of change.