Filters and welding equipment

Abstract

The present application discloses a filtering device and a welding device, which are applied to the field of welding technology. The filtering device is applied to the welding device, and the filtering device includes a capacitor, one end of the capacitor is connected to the welding head of the welding device, and the other end is connected to the ground terminal, so that the output voltage of the welding head is within a preset voltage range. Through an external filtering device, the welding head is connected to the ground terminal through the capacitor. When the output voltage of the welding head fluctuates instantaneously, the capacitor immediately plays a protective role, thereby avoiding excessive fluctuations in the output voltage of the welding head, so that the output voltage of the welding head is always within the preset voltage range. In this way, even if the welding head contacts the antenna pad of the chip, since the output voltage of the welding head is always within the preset voltage range, the impact on the circuit under the antenna pad is also small, and the performance of the chip will not be affected, thereby avoiding the problem of serious degradation or failure of RF performance during the welding process, and improving the production yield of communication cards.

Description

Technical Field

[0001] The present application relates to the field of welding technology, and in particular to a filtering device and welding equipment. Background Art

[0002] The existing smart card packaging is a soldering mode, such as Figure 1 The figure shows the connection between the coil of a special dual-interface card with a resonant frequency of 13.56MHz and the dual-interface module. The welding machine welds the antenna coil head on the card base to the antenna pads at both ends of the smart card module through discharge. When a card reader with a specific protocol and power is close, normal communication can be carried out.

[0003] However, since the contact electrostatic discharge (ESD) protection of the antenna pad was not considered during chip design, the welding machine impacted the chip circuit under the antenna pad when welding the antenna to the antenna pad, causing the RF performance to seriously degrade or fail, affecting the yield of the smart card. Summary of the invention

[0004] The embodiments of the present application provide a filtering device and a welding device.

[0005] The filtering device of the embodiment of the present application is applied to welding equipment, and the filtering device includes a capacitor, one end of which is connected to the welding head of the welding equipment, and the other end is connected to the ground, so that the output voltage of the welding head is within a preset voltage range.

[0006] In some embodiments, the capacitance value of the capacitor is determined based on an equivalent resistance of the filter device and a frequency of the output voltage, and the equivalent resistance is determined based on a peak voltage of the output voltage.

[0007] In some embodiments, the capacitance value of the capacitor is greater than 8 microfarads, and the rated voltage of the capacitor is greater than the peak voltage.

[0008] In some embodiments, the maximum value of the preset voltage range is less than a preset safety voltage of a communication card welded by the welding device.

[0009] In some embodiments, the filtering device includes an insulating housing, and the capacitor is disposed in the insulating housing.

[0010] In some embodiments, the insulating housing is a plastic housing.

[0011] In some embodiments, the filtering device further includes a first circuit and a second circuit, the first circuit and the second circuit pass through the insulating shell, and the welding head, the first circuit, the capacitor, the second circuit and the grounding terminal are connected in sequence.

[0012] In some embodiments, the total length of the first line and the second line is greater than the maximum distance between the welding head and the ground end when the welding head moves within a preset range of motion.

[0013] In some embodiments, the first line and the second line include at least one of a silicone rubber insulated wire, a fluoroplastic insulated wire, a glass fiber insulated wire, a ceramic fiber insulated wire, a metal braided shielded wire, and a mineral insulated wire.

[0014] The welding equipment of the present application includes a welding head and a filtering device of any one of the above-mentioned embodiments.

[0015] In some embodiments, the welding device further includes a driving component, the welding head is disposed in the driving component, the driving component includes a conductive member, the conductive member is electrically connected to the welding head, and the capacitor is connected to the welding head by connecting the conductive member.

[0016] In some embodiments, the welding device further includes a housing, and the grounding terminal is located in the housing.

[0017] In some embodiments, the welding device is used to weld the antenna and chip of a communication card.

[0018] In some embodiments, the chip includes an antenna pad, the antenna pad is provided with solder, the antenna includes an antenna coil and an enameled wire, and the welding head is used for discharging to melt the solder and the insulating varnish on the surface of the enameled wire so that the solder is connected to the wire in the enameled wire.

[0019] In some embodiments, the communication card comprises a dual interface smart card.

[0020] In the filtering device and welding equipment of the implementation mode of the present application, the welding head is connected to the ground terminal through a capacitor through an external filtering device. When the output voltage of the welding head fluctuates instantaneously, the capacitor immediately plays a protective role, thereby avoiding excessive fluctuations in the output voltage of the welding head, so that the output voltage of the welding head is always within the preset voltage range.

[0021] In this way, even if the welding head contacts the antenna pad of the chip, since the output voltage of the welding head is always within the preset voltage range, the impact on the circuit under the antenna pad is also small, and the performance of the chip will basically not be affected, thereby avoiding the problem of serious degradation or failure of RF performance during the welding process, and improving the production yield of communication cards.

[0022] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and / or additional aspects and advantages of the embodiments of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0024] Figure 1 It is a plan view of a communication card according to certain embodiments of the present application.

[0025] Figure 2 This is a waveform diagram of the output voltage of the welding head when no filtering device is installed in certain embodiments of the present application.

[0026] Figure 3 It is a schematic diagram of the structure of welding equipment in certain embodiments of the present application.

[0027] Figure 4 This is a waveform diagram of the output voltage of the welding head when a filtering device is installed in certain embodiments of the present application. DETAILED DESCRIPTION

[0028] The following further describes the embodiments of the present application in conjunction with the accompanying drawings. The same or similar reference numerals in the accompanying drawings represent the same or similar elements or elements with the same or similar functions.

[0029] In addition, the embodiments of the present application described below in conjunction with the drawings are exemplary and are only used to explain the embodiments of the present application and should not be construed as limiting the present application.

[0030] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0031] For ease of understanding, the technical background and application scenarios of this application are first introduced below:

[0032] Communication card: usually refers to various smart cards used for data exchange and communication. These cards can be used for a variety of different applications, including but not limited to identity authentication, payment, access control, etc. For example, the Dual Interface Smart Card is a smart card technology that combines contact and contactless communication functions. It contains two independent operating interfaces, one is the traditional contact operating interface, usually based on the 7816 standard, used to handle applications that require physical contact, such as financial transactions; the other is a contactless operating interface, usually based on the ISO 14443 standard, which supports fast data reading and small payment operations, such as public transportation cards, access control systems, etc.

[0033] The packaging form of the existing dual-interface smart card is a touch welding mode, such as Figure 1 The figure shows the connection method between the coil of the dual-interface card with a special resonance frequency of 13.56MHz and the dual-interface module.

[0034] During welding, the present application can weld the antenna coil head on the card base to the antenna pads at both ends of the smart card module. The outside of the antenna is wrapped with insulating paint to form an enameled wire, and the antenna can conduct electricity; there is solder on the antenna pad, and the welding head of the touch welding machine is close to the antenna pad, and then discharges instantly, relying on a large current to melt the solder, and at the same time, the high temperature melts the insulating paint on the enameled wire of the antenna. The solder wraps the conductive part of the antenna during the solidification process, so that the antenna and the chip will form a closed circuit through the antenna pad. When a card reader with a specific protocol and power is close, normal communication can be carried out.

[0035] In production, due to the instantaneous high-frequency and high-voltage power burrs of the welding head, such as Figure 2 The waveform shown is the output voltage of the welding head. The instantaneous peak-to-peak voltage during welding will exceed 180 volts (V) (normal peak-to-peak voltage is about 15V). This instantaneous high voltage will impact the chip and damage the RF function of the chip, which will be manifested as a shortened communication distance of contactless communication (less than 2 centimeters (cm), normally 5cm-10cm) or poor contactless communication. When quality inspection is performed after welding, cards with poor contactless communication will frequently appear, affecting the yield of smart cards. And the machine needs to be stopped for confirmation, which greatly affects the welding efficiency of the welding machine.

[0036] Currently, there are several solutions, but all of them have some problems to a greater or lesser extent.

[0037] For example, surge protection: installing appropriate surge protection devices, such as TVS diodes or suppressors, can absorb energy when the power line is hit by an overvoltage shock and prevent it from being directly transmitted to the chip. However, due to the long response time, it cannot immediately protect the circuit from transient events and the effect is poor.

[0038] Another example is power supply monitoring: by monitoring the power supply voltage, when a glitch is detected, the power supply is automatically adjusted or cut off to avoid continued damage. For mass-produced products, this method will interfere with the continuity of production and greatly reduce the production capacity of the equipment.

[0039] Another example is hardware design optimization: adopting anti-interference design strategies, such as adding a shielding layer to the power line and reducing the close distance between the signal line and the power line. This method will increase the extra circuit area and power consumption, and although it can avoid the impact of the processing process, it is not worth the loss.

[0040] See also Figure 3 The filter device 10 of the present application is applied to a welding device 100. The filter device 10 includes a capacitor 11. One end of the capacitor 11 is connected to a welding head 20 of the welding device 100, and the other end is connected to a ground terminal 30, so that the output voltage of the welding head 20 is within a preset voltage range.

[0041] The capacitor 11 can be used to protect the circuit from the impact of transient voltage by absorbing the transient voltage spike and converting it into heat energy to dissipate it.

[0042] For example, capacitor 11 can realize the functions of ESD protection and overvoltage protection. ESD protection: capacitor 11 is used in the interface circuit to absorb the energy of electrostatic discharge (ESD) to protect sensitive electronic components. Overvoltage protection: capacitor 11 is used at the power input end to absorb transient overvoltage to prevent damage to subsequent circuits.

[0043] During the process of welding the antenna 201 of the smart card to the antenna pad 203 by the welding head 20, if the output voltage of the welding head 20 fluctuates instantaneously, such as from 15V to 180V, at this time, due to the action of the capacitor 11, the capacitor 11 stores additional charge, thereby reducing the voltage output from the welding head 20 to the antenna pad 203, thereby achieving voltage protection, so that the output voltage of the welding head 20 is always within the preset voltage range (such as 0-20V).

[0044] Compared with the disadvantages of the above-mentioned solutions, the present application connects an external filter device 10 to the welding equipment 100, and connects the welding head 20 to the ground terminal 30 through the capacitor 11. When the output voltage of the welding head 20 fluctuates instantaneously, the capacitor 11 immediately plays a protective role, thereby avoiding excessive instantaneous fluctuations in the output voltage of the welding head 20, so that the output voltage of the welding head 20 is always within the preset voltage range.

[0045] In this way, even if the welding head 20 contacts the antenna pad 203 of the chip 202, since the output voltage of the welding head 20 is always within the preset voltage range, the impact on the circuit under the antenna pad 203 is also small, and the performance of the chip 202 is basically not affected, thereby avoiding the problem of serious degradation or failure of radio frequency performance during welding, and improving the production yield of the communication card 200. And the improvement of the yield of smart cards can reduce the probability of shutdown confirmation and improve the welding efficiency of the welding machine. In addition, the filter device 10 only needs to be provided with a capacitor 11 and a wire, and the cost is also low.

[0046] In some embodiments, the capacitance value of the capacitor 11 is determined based on the equivalent resistance of the filter device 10 and the frequency of the output voltage, and the equivalent resistance is determined based on the peak voltage of the output voltage.

[0047] Specifically, in order to ensure that the capacitor 11 can protect the circuit of the smart card, it is necessary to reasonably set the capacitance value of the capacitor 11. The capacitance value of the filter capacitor 11 determines its filtering effect on high-frequency noise. To determine the capacitance value of the filter capacitor 11, the formula: C = To calculate, C represents the capacitance of the filter capacitor 11 (unit: Farad (F), f is the frequency of the high-frequency noise to be filtered out (unit: Hertz 9 Hz), and R is the equivalent resistance of the load resistor and capacitor 11 in the circuit (unit: ohm (Ω)).

[0048] The peak voltage, current, equivalent resistance and frequency of high-frequency noise of the output voltage of the welding machine can be obtained through experimental calibration. For example, the peak voltage is 180V and the current is 10 amperes (A), so the equivalent resistance of the load is 18Ω, and the frequency of the high-frequency noise is 1KHz. Substituting the above formula into the calibrated capacitance value of the filter capacitor 11 is 8.84uF. In this way, you can choose a calibrated capacitance value with a rated voltage greater than 180V (to ensure that the capacitor 11 will not be damaged by the peak voltage) and a capacitance value greater than 8.84uF. In order to further ensure stability, the filter capacitor 11 with a rated voltage of 200V and a capacitance value of 10uF commonly used in the market can be selected.

[0049] Optionally, based on the difference of the actually used welding machine, the calibration capacitance value is also different, such as the calibration capacitance value is greater than or equal to 8uF.

[0050] In some embodiments, the maximum value of the preset voltage range is less than a preset safety voltage of the communication card 200 welded by the welding device 100 .

[0051] Specifically, after the filter device 10 is set, the output voltage can be output when the touch welding of the smart card is actually performed by the touch welding machine to detect the range of the output voltage. If the maximum voltage in the range of the output voltage is less than the preset safety voltage of the communication card 200, it can be determined that the capacitor 11 is set effectively. If the maximum voltage in the range of the output voltage is greater than the preset safety voltage of the communication card 200, it can be determined that the capacitor 11 is set with a problem, and it is necessary to replace the capacitor 11 with a larger capacitance value, thereby ensuring that the output voltage of the touch welding machine of the external filter device 10 is always in the preset voltage range, and the maximum output voltage is less than the preset safety voltage.

[0052] The preset safety voltage of the communication card 200 is the maximum voltage that the antenna pad 203 of the communication card 200 can withstand. If the voltage input to the antenna pad 203 is greater than the preset safety voltage, the communication card 200 will be damaged.

[0053] In some embodiments, the filter device 10 includes an insulating housing 12 , and the capacitor 11 is disposed in the insulating housing 12 .

[0054] Specifically, in order to prevent other electrical components of the welding equipment from affecting the capacitor 11, the filter device 10 can be set in the insulating shell 12, and then the insulating shell 12 is opened to connect the welding head 20 and the grounding terminal 30 through the wire via.

[0055] Optionally, the insulating housing 12 may be sealed to prevent conductive materials in the production environment from entering the insulating housing 12 and affecting the capacitor 11 .

[0056] Optionally, the insulating shell 12 may be made of an insulating material, such as the insulating shell 12 may be a plastic shell.

[0057] In some embodiments, the filter device 10 further includes a first circuit 13 and a second circuit 14, the first circuit 13 and the second circuit 14 pass through the insulating housing 12, and the welding head 20, the first circuit 13, the capacitor 11, the second circuit 14 and the ground terminal 30 are connected in sequence.

[0058] Specifically, in order to achieve the connection of the capacitor 11, the filtering device 10 also includes a first circuit 13 and a second circuit 14. The first circuit 13 is used to connect the capacitor 11 and the welding head 20, and the second circuit 14 is used to connect the capacitor 11 and the ground terminal 30. In this way, the welding head 20, the first circuit 13, the capacitor 11, the second circuit 14 and the ground terminal 30 are connected in sequence to form a conductive loop.

[0059] When the welding head 20 outputs a voltage, the charge is sequentially conducted from the welding head 20, the first line 13, the capacitor 11, the second line 14 and the ground terminal 30 to the ground terminal 30. When the output voltage of the welding head 20 fluctuates instantaneously, the capacitor 11 immediately plays a protective role and stores extra charge, thereby preventing the output voltage of the welding head 20 from fluctuating too much, so that the output voltage of the welding head 20 is always within the preset voltage range.

[0060] Optionally, the total length of the first line 13 and the second line 14 is greater than the maximum distance between the welding head 20 and the ground terminal 30 when the welding head 20 moves within a preset range of motion.

[0061] Specifically, since the welding head 20 is a moving part, in order to prevent the welding head 20 from pulling and breaking the first line 13 and / or the second line 14 during the movement of the welding head 20, the lengths of the first line 13 and the second line 14 need to be reasonably set. For example, by calibrating the maximum distance between the welding head 20 and the ground terminal 30 when the welding head 20 moves within a preset range of motion, the total length of the first line 13 and the second line 14 can be set to be greater than the maximum distance, thereby ensuring the operational stability of the filter device 10.

[0062] Optionally, the first line 13 and the second line 14 include at least one of a silicone rubber insulated wire, a fluoroplastic insulated wire, a glass fiber insulated wire, a ceramic fiber insulated wire, a metal braided shielded wire, and a mineral insulated wire.

[0063] Specifically, in order to further prevent the first line 13 and / or the second line 14 from being pulled and broken, and to ensure that the filter device 10 can stably protect the circuit on the smart card, the first line 13 and the second line 14 can be set as wear-resistant and high-temperature resistant soft wires, such as at least one of silicone rubber insulated wires, fluoroplastic insulated wires, glass fiber insulated wires, ceramic fiber insulated wires, metal braided shielded wires, and mineral insulated wires.

[0064] Optionally, when the filter device 10 is installed, the first line 13 and the second line 14 are kept in a relaxed state and are not bent as much as possible, so as to avoid generating additional inductance and affecting the filtering effect of the filter device 10 .

[0065] The welding device 100 of the present application includes a welding head 20 and a filter device 10 of any of the above embodiments. The welding device 100 is used to weld an antenna 201 and a chip 202 of a communication card 200 to realize a contactless communication function of the communication card 200.

[0066] The filter device 10 can be mounted on the welding device 100 as an external device to improve the flexibility of the welding device 100. The filter device 10 supports multiple disassembly and installation, and after installation, it can provide effective protection for any device that requires voltage protection. Alternatively, the filter device 10 can be used as one of the components of the welding device 100, thereby improving the integrity of the welding device 100.

[0067] Optionally, the welding device 100 includes a plurality of welding heads 20, and the welding and packaging of a plurality of smart cards can be realized simultaneously through the plurality of welding heads 20, thereby improving the welding efficiency of the smart cards.

[0068] In some embodiments, the welding device 100 further includes a driving component 40 , the welding head 20 is disposed in the driving component 40 , the driving component 40 includes a conductive member 41 , the conductive member 41 is electrically connected to the welding head 20 , and the capacitor 11 is connected to the welding head 20 via the conductive member 41 .

[0069] Specifically, the welding device 100 is further provided with a driving assembly 40 for driving the welding head 20 to move. For example, the driving assembly 40 also includes a motor 42, and the driving motor 42 is rotated to drive the welding head 20 to operate. A conductive member 41 is provided in the driving assembly 40, and the welding head 20 is connected to the power source through the conductive member 41 (such as a wire, a component made of a metal material, etc.). If the welding head 20 is connected to the conductive member 41, the conductive member 41 is connected to the power source.

[0070] Optionally, the conductive member 41 may not move with the welding head 20. In this case, the first circuit 13 is connected to the conductive member 41. In this way, when the welding head 20 moves, it will not drive the first circuit 13 and the second circuit 14 to move. As a result, the first circuit 13 and the second circuit 14 only need to be connected to the conductive member 41 and the ground terminal 30. The problem of the circuit being pulled and broken will not occur, thereby ensuring the operating stability of the filtering device 10.

[0071] In some embodiments, the welding device 100 further includes a housing 50 , the driving assembly 40 may be disposed on the housing 50 , and the ground terminal 30 is located on the housing 50 .

[0072] In this way, the housing 50 can be used as the ground terminal 30 , thereby being connected to the second line 14 , so as to realize the filtering function of the filter device 10 on the output voltage.

[0073] Optionally, before installing the filter device 10 , the ground terminal 30 needs to be tested to ensure that the potential point of the ground terminal 30 is grounded normally.

[0074] In some embodiments, the chip 202 includes an antenna pad 203, the antenna pad 203 is provided with solder, the antenna 201 includes an antenna coil and an enameled wire, and the welding head 20 is used for discharging to melt the solder and the insulating paint on the surface of the enameled wire so that the solder is connected to the wire in the enameled wire.

[0075] like Figure 3 and 4 As shown, the present application can verify whether the filter device 10 meets the requirements by using an oscilloscope to measure the waveform of the output voltage of the welding head 20 before and after the filter device 10 is installed. For example, after the filter device 10 is installed, the peak value of the waveform of the output voltage is significantly suppressed and reduced to below 20V, thereby ensuring that the output voltage of the welding head 20 is always within the preset voltage range (such as 0 to 20V), and it can be determined that the filter device 10 meets the requirements.

[0076] In order to more accurately verify whether the filter device 10 meets the requirements. It can be achieved by verifying whether the yield rate of the smart card welded by the welding equipment 100 after the filter device 10 is installed is significantly improved. For example, a card sealing test can be performed by using a variety of different types of smart cards, each of which is packaged with 10,000 cards, so as to detect the proportion of smart cards whose non-contact communication performance is reduced or failed due to contact welding. When the proportion is less than the preset proportion, it can be determined that the yield rate of the smart card welded by the welding equipment 100 after the filter device 10 is installed is significantly improved, and when the proportion is greater than or equal to the preset proportion, it can be determined that the yield rate of the smart card welded by the welding equipment 100 after the filter device 10 is installed is not significantly improved.

[0077] When the yield rate of smart cards welded by the welding device 100 after the filter device 10 is installed is significantly improved, it is determined that the filter device 10 meets the requirements. When the yield rate of smart cards welded by the welding device 100 after the filter device 10 is installed is not significantly improved, it is determined that the filter device 10 does not meet the requirements. In this case, the filter device 10 is readjusted (such as increasing the capacitance value of the capacitor 11 of the filter device 10, or adding a capacitor 11, etc.) until the filter device 10 meets the requirements.

[0078] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0079] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one feature. In the description of this application, the meaning of "plurality" is at least two, such as two, three, unless otherwise clearly and specifically defined.

[0080] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A welding device, characterized in that: The welding equipment comprises: Welding head; A filtering device, the filtering device comprising: A capacitor, one end of which is connected to a welding head of the welding device, and the other end of which is connected to a ground terminal, so that an output voltage of the welding head is within a preset voltage range; The welding device further comprises a driving assembly, the welding head is arranged on the driving assembly, the driving assembly comprises a conductive member, the conductive member is electrically connected to the welding head, and the capacitor is connected to the welding head by connecting the conductive member; The filtering device further comprises a first circuit and a second circuit, wherein the first circuit connects the conductive member and the capacitor, and the second circuit connects the capacitor and the ground terminal; The driving assembly drives the welding head to move, and the conductive member does not move with the welding head; The maximum value of the preset voltage range is less than the preset safety voltage of the communication card welded by the welding equipment; The welding equipment is used to weld the antenna and chip of the communication card; The chip includes an antenna pad, the antenna pad is provided with solder, the antenna includes an antenna coil and an enameled wire, and the welding head is used for discharging to melt the solder and the insulating varnish on the surface of the enameled wire so that the solder is connected to the wire in the enameled wire.

2. The welding device according to claim 1, characterized in that It also includes a shell, and the grounding terminal is located in the shell.

3. The welding device according to claim 1, characterized in that The communication card comprises a dual-interface smart card.

4. The welding equipment according to claim 1, wherein a capacitance value of the capacitor is determined based on an equivalent resistance of the filter device and a frequency of the output voltage, and the equivalent resistance is determined based on a peak voltage of the output voltage.

5. The welding device according to claim 4, characterized in that The capacitance value of the capacitor is greater than 8 microfarads, and the rated voltage of the capacitor is greater than the peak voltage.

6. The welding device according to claim 1, characterized in that The filter device comprises an insulating shell, and the capacitor is arranged in the insulating shell.

7. The welding device according to claim 6, characterized in that The insulating shell is a plastic shell.

8. The welding device according to claim 1, characterized in that The first line and the second line include at least one of a silicone rubber insulated wire, a fluoroplastic insulated wire, a glass fiber insulated wire, a ceramic fiber insulated wire, a metal braided shielded wire, and a mineral insulated wire.

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