Ultrasonic generator conditioning device, ultrasonic generator and ultrasonic welding apparatus

Abstract

The application provides an ultrasonic generator adjusting device, an ultrasonic generator and an ultrasonic welding device, and relates to the technical field of ultrasonic waves.The device comprises a first timer, a PID controller and a second timer, the PID controller is connected to the first timer, and the second timer is connected to the first timer.The first timer is used to determine the phase offset of a current zero-crossing signal and a voltage zero-crossing signal.The PID controller is used to generate a phase adjustment signal according to the size of the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.The second timer is used to generate a driving signal of an upper tube of a first bridge arm of the ultrasonic generator and a driving signal of a lower tube of the first bridge arm of the ultrasonic generator, so as to reduce the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.The application has the technical effect that the phase offset between the current signal and the voltage signal is effectively eliminated, the ultrasonic generator is stably operated in a resonant state, and therefore the ultrasonic welding performance and quality are improved.

Description

Technical Field

[0001] This application relates to the field of ultrasonic technology, specifically to an ultrasonic generator adjustment device, an ultrasonic generator, and an ultrasonic welding equipment. Background Technology

[0002] Ultrasonic welding technology is widely used in industrial welding, with the ultrasonic generator being the core device for achieving ultrasonic welding. The ultrasonic generator converts electrical energy into high-frequency electrical energy, which is then converted into mechanical vibrations of the same frequency by a transducer. This mechanical vibration is transmitted to the welding area, causing it to melt and form a weld bond, thus achieving ultrasonic welding of metal materials. However, existing ultrasonic generators suffer from phase shift between the current and voltage signals, which can cause the generator to operate in an unstable state, affecting the quality of ultrasonic welding. Summary of the Invention

[0003] This application provides an ultrasonic generator adjustment device for effectively eliminating the phase shift between current and voltage signals, enabling the ultrasonic generator to operate stably in a resonant state, thereby improving the performance and quality of ultrasonic welding.

[0004] In a first aspect, this application provides an ultrasonic generator adjustment device, the device comprising: a first timer, a PID controller, and a second timer, wherein the PID controller is connected to the first timer, and the second timer is connected to the first timer; the first timer is configured to acquire the current zero-crossing signal and the voltage zero-crossing signal of the ultrasonic generator, and determine the phase offset of the current zero-crossing signal and the voltage zero-crossing signal, and the reset port of the first timer is configured to receive the current zero-crossing signal; the PID controller is configured to generate a phase adjustment signal based on the magnitude of the phase offset of the current zero-crossing signal and the voltage zero-crossing signal, and output it to the first timer; the second timer is configured to generate a drive signal for the upper tube of the first bridge arm of the ultrasonic generator and a drive signal for the lower tube of the first bridge arm of the ultrasonic generator based on the adjustment signal, so as to reduce the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.

[0005] By employing the above technical solution, a first timer, a PID controller, and a second timer are used to achieve digital closed-loop control of the ultrasonic generator. This eliminates the phase shift between the current and voltage zero-crossing signals, ensuring the ultrasonic generator operates stably in a resonant state. The first timer acquires the current and voltage zero-crossing signals from the ultrasonic generator and calculates the phase shift between them. The PID controller outputs a phase adjustment signal to the first timer based on the magnitude of the phase shift. The first timer controls the second timer based on the phase adjustment signal. The second timer ultimately generates the drive signals for the upper and lower pipes of the ultrasonic generator bridge arm. Through this cascaded control, the drive signal of the ultrasonic generator can be dynamically adjusted, gradually reducing the phase shift between the current and voltage zero-crossing signals until it approaches zero, achieving frequency locking. This effectively eliminates the phase shift between the current and voltage signals, ensuring the ultrasonic generator operates stably in a resonant state, thereby improving the performance and quality of ultrasonic welding.

[0006] Optionally, the PID controller is configured to: decrease the value of the phase adjustment signal to increase the phase offset between the drive signal of the first bridge arm transistor and the current zero-crossing signal when the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is greater than 0; and increase the value of the phase adjustment signal to decrease the phase offset between the drive signal of the first bridge arm transistor and the current zero-crossing signal when the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is less than 0.

[0007] By employing the above technical solution, when a positive phase shift is detected between the current zero-crossing signal and the voltage zero-crossing signal, the PID controller will correspondingly decrease the value of the output phase adjustment signal; conversely, when a negative phase shift is detected, the value of the phase adjustment signal will increase. This phase adjustment signal regulates the drive signal of the first bridge arm circuit, thereby changing the phase relationship between the drive signal of the upper tube of the first bridge arm and the current zero-crossing signal. In the case of a positive phase shift, the phase difference between the upper tube drive signal and the current zero-crossing signal is increased; while in the case of a negative phase shift, the phase difference between the upper tube drive signal and the current zero-crossing signal is decreased. Through the phase closed-loop control of the PID controller, the phase adjustment signal can be accurately generated, thereby effectively adjusting the phase shift of the ultrasonic generator and improving the accuracy of phase control. This is one of the key technologies for achieving precise control of the ultrasonic generator in this generator adjustment device.

[0008] Optionally, the first timer is further configured to determine the period of the current zero-crossing signal; the second timer is further configured to set the period of the drive signal of the upper tube of the first bridge arm and the period of the drive signal of the lower tube of the first bridge arm to half the period of the current zero-crossing signal according to the period of the current zero-crossing signal.

[0009] By adopting the above technical solution, the second timer sets the drive signal period of the upper and lower tubes of the first bridge arm to half the period of the current zero-crossing signal detected by the first timer. This is equivalent to setting the drive signal frequency of the bridge arm circuit to twice the current signal frequency. Using a drive signal synchronized with the current signal period ensures the synchronicity between the drive signal and the current signal, thereby improving the control accuracy of the driven bridge arm circuit. The effectiveness of phase closed-loop control depends on accurate drive time; adding a design that generates drive time based on the current signal period can further improve the accuracy of phase closed-loop control. Through the drive time generation method synchronized with the current signal, this technical solution enhances the ultrasonic generator adjustment device's ability to precisely control the generator's phase, improving the phase adjustment effect of the ultrasonic generator.

[0010] Optionally, the processor is configured to: when the output power of the ultrasonic generator is greater than the set power, decrease the value of the power adjustment signal to increase the phase shift between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube; and when the output power of the ultrasonic generator is less than the set power, increase the value of the power adjustment signal to decrease the phase shift between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube.

[0011] By adopting the above technical solution, the processor can calculate the actual power based on the detected output current and voltage of the ultrasonic generator, compare it with the preset power setting, and generate a power adjustment signal based on the comparison result. The power adjustment signal is used to control the driving timing of the second bridge arm circuit, thereby changing the phase relationship between the driving signals of the upper and lower tubes of the second bridge arm. When the output power is too high, the phase difference between the driving signals of the upper and lower tubes is increased; when the output power is too low, the phase difference between the driving signals of the upper and lower tubes is decreased. Through closed-loop power control, the processor can accurately output the power adjustment signal to drive the second bridge arm circuit to change the output power of the ultrasonic generator, bringing it closer to the preset power setting. Combined with the phase closed-loop control of the first bridge arm circuit, dual closed-loop control of the ultrasonic generator's output power and phase is achieved, improving the control accuracy of the ultrasonic generator adjustment device and enhancing the adjustability of the ultrasonic generator's output performance.

[0012] Optionally, the third timer is connected to the first timer; the third timer is used to generate a drive signal for the upper tube of the second bridge arm of the ultrasonic generator and a drive signal for the lower tube of the second bridge arm of the ultrasonic generator according to the adjustment signal, so as to reduce the phase shift of the current zero-crossing signal and the voltage zero-crossing signal.

[0013] By employing the above technical solution, the third timer, based on the phase adjustment signal of the first timer, changes the phase relationship between the drive signals of the upper and lower tubes of the second bridge arm, thereby adjusting the output phase of the ultrasonic generator. When the phase adjustment signal of the first timer detects a positive phase shift between the current zero-crossing signal and the voltage zero-crossing signal, the third timer correspondingly reduces the phase difference between the drive signals of the upper and lower tubes of the second bridge arm to reduce the positive phase shift. When a negative phase shift is detected, the third timer correspondingly increases the phase difference between the drive signals of the upper and lower tubes to reduce the negative phase shift. Position offset. By using a third timer to drive the second bridge arm circuit based on the phase adjustment signal of the first timer, additional phase adjustment can be provided, improving the effect of phase closed-loop control and enhancing the range and accuracy of phase adjustment of the ultrasonic generator.

[0014] Optionally, the third timer is further configured to set the period of the drive signal of the upper tube of the second bridge arm and the period of the drive signal of the lower tube of the second bridge arm to half the period of the current zero-crossing signal, based on the period of the current zero-crossing signal.

[0015] By adopting the above technical solution, the third timer sets the drive signal period of the upper and lower tubes of the second bridge arm to half the period of the current zero-crossing signal detected by the first timer. This is equivalent to setting the drive signal frequency of the second bridge arm to twice the current signal frequency. Using a second bridge arm drive signal synchronized with the current signal period ensures the synchronization between the drive signal and the current signal, thereby improving the control accuracy of the second bridge arm. The effectiveness of phase closed-loop control depends on precise drive timing control. Adding a design to generate the second bridge arm drive timing based on the current signal period can further improve the accuracy of phase closed-loop control. Through the second bridge arm drive timing generation method synchronized with the current signal, this technical solution enhances the ability of the ultrasonic generator adjustment device to precisely control the generator phase and improves the phase adjustment effect of the ultrasonic generator.

[0016] Optionally, the device further includes a detection module, which is connected to the ultrasonic generator, the first timer, and the analog-to-digital converter respectively. The detection module is used to acquire and detect the current output signal of the ultrasonic generator to obtain the current zero-crossing signal and the current DC signal of the ultrasonic generator, and to acquire and detect the voltage output signal of the ultrasonic generator to obtain the voltage zero-crossing signal and the voltage DC signal of the ultrasonic generator.

[0017] By adopting the above technical solution, the detection module directly acquires the raw current and voltage information inside the ultrasonic generator, eliminating intermediate signal transmission links and improving the accuracy and speed of parameter acquisition. The detected current zero-crossing signal is output to the first timer, enabling it to accurately determine the operating status of the ultrasonic generator, which is the foundation for subsequent precise phase control. Simultaneously, the current and voltage DC signals are output to the analog-to-digital converter, allowing it to accurately acquire the output current and voltage of the ultrasonic generator as a basis for calculating the output power. By directly acquiring key parameters of the ultrasonic generator, detection accuracy and speed are improved, providing crucial support for subsequent phase and power closed-loop control and enhancing the control performance and effectiveness of the ultrasonic generator adjustment device.

[0018] Secondly, this application provides an ultrasonic generator, which includes a first upper bridge tube, a first lower bridge tube, a second upper bridge tube, a second lower bridge tube, and an ultrasonic generator adjustment device. A first end of the first upper bridge tube is connected to a first end of the second upper bridge tube, a second end of the first upper bridge tube is connected to a first end of the first lower bridge tube and serves as a first output end of the ultrasonic generator, a second end of the first upper bridge tube is connected to a first end of the first lower bridge tube and serves as a second output end of the ultrasonic generator, and a second end of the first lower bridge tube is connected to a second end of the second lower bridge tube.

[0019] By adopting the above technical solution and designing it from both hardware circuit and control logic aspects, the driving and control of the ultrasonic generator are highly coordinated and unified. The overall effect is to significantly enhance the closed-loop control capability of the ultrasonic generator's phase and power adjustment and improve the output control performance.

[0020] Thirdly, this application provides an ultrasonic welding device, the device including a welding head, an amplitude transformer, a transducer and the ultrasonic generator, the transducer being electrically connected to the ultrasonic generator, and the amplitude transformer being mechanically connected to the transducer and the welding head respectively.

[0021] By adopting the above technical solution, the ultrasonic generator emits a precisely controlled electrical signal, which is converted into mechanical vibration by the transducer, amplified by the amplitude converter, and transmitted to the welding head. This drives the welding head to output powerful mechanical vibration according to the required characteristics, achieving a high-precision ultrasonic welding process. In summary, this solution effectively improves the output effect of ultrasonic welding equipment, giving it higher precision welding capabilities. Therefore, this application includes at least one of the following beneficial technical effects: 1. Effectively eliminates the phase shift between current and voltage signals, enabling the ultrasonic generator to operate stably in a resonant state, thereby improving the performance and quality of ultrasonic welding; 2. The ultrasonic generator emits a precisely controlled electrical signal, which is converted into mechanical vibration by the transducer, and then amplified by the amplitude converter and transmitted to the welding head, thereby driving the welding head to output powerful mechanical vibration according to the required characteristics, realizing a high-precision ultrasonic welding process. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of an ultrasonic generator adjustment device provided in an embodiment of this application; Figure 2 This is a schematic diagram of another adjustment device for an ultrasonic generator provided in an embodiment of this application; Figure 3 This is a schematic diagram of another adjustment device for an ultrasonic generator provided in an embodiment of this application; Figure 4 This is a structural schematic diagram of an ultrasonic welding device provided in an embodiment of this application. Detailed Implementation

[0023] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0024] In the description of the embodiments in this application, words such as "illustrative," "for example," or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "illustrative," "for example," or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Rather, the use of words such as "illustrative," "for example," or "for example" is intended to present the relevant concepts in a specific manner.

[0025] Please see Figure 1 , Figure 1 This is a schematic diagram of an ultrasonic generator adjustment device provided in an embodiment of this application. The device includes: a first timer, a PID controller, and a second timer, wherein the PID controller is connected to the first timer, and the second timer is connected to the first timer; The first timer is used to acquire the current zero-crossing signal and the voltage zero-crossing signal of the ultrasonic generator, and to determine the phase offset of the current zero-crossing signal and the voltage zero-crossing signal. The reset port of the first timer is used to receive the current zero-crossing signal. The PID controller is used to generate a phase adjustment signal based on the phase offset between the current zero-crossing signal and the voltage zero-crossing signal and output it to the first timer. The second timer is used to generate drive signals for the upper tube of the first bridge arm of the ultrasonic generator and the lower tube of the first bridge arm of the ultrasonic generator according to the adjustment signal, so as to reduce the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.

[0026] In one example, the first timer acquires the current zero-crossing signal (IZC) and voltage zero-crossing signal (VZC) of the ultrasonic generator. These signals are then sent to the PID controller. Upon receiving the IZC and VZC signals from the first timer, the PID controller calculates a phase adjustment control signal using a PID algorithm based on the sign and magnitude of the offset. The PID controller then sends this phase adjustment control signal back to the first timer.

[0027] The phase adjustment control signal can be configured to increase the phase when the offset is positive and decrease the phase when the offset is negative. The control signal carries information about the direction and degree of phase adjustment. The PID algorithm can perform complex calculations to accurately generate the control signal, which is crucial for achieving high-precision control.

[0028] When the first timer receives the phase adjustment control signal from the PID controller, it sends an adjustment signal to the second timer. Upon receiving the adjustment signal from the first timer, the second timer changes the phase of the drive waveforms of the upper and lower pipes of the first bridge arm. When the phase difference is greater than 0, the phase of the upper bridge arm drive waveform is decreased; when the phase difference is less than 0, the phase of the upper bridge arm drive waveform is increased. Through this closed-loop control, the switching time of the upper and lower pipes of the drive bridge arm can be adjusted, thereby changing the output frequency of the ultrasonic generator. By changing the phase of the drive waveforms of the upper and lower pipes of the first bridge arm, the output of the ultrasonic generator can be adjusted, eliminating the phase difference between the current and voltage signals, ultimately completing closed-loop control of the output frequency. This system achieves precise control of the ultrasonic generator frequency through the linkage of the first timer, the PID controller, and the second timer, improving the stability of ultrasonic welding.

[0029] The PID controller is used to: decrease the value of the phase adjustment signal when the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is greater than 0, so as to increase the phase offset between the drive signal of the first bridge arm transistor and the current zero-crossing signal; and increase the value of the phase adjustment signal when the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is less than 0, so as to decrease the phase offset between the drive signal of the first bridge arm transistor and the current zero-crossing signal.

[0030] In another example, the phase shift (phase difference signal) between the current and voltage zero-crossing signals is detected in real time. A phase adjustment control signal is generated based on the sign and magnitude of this difference to adjust the phase of the drive waveform of the upper transistor in the first bridge arm. When the phase difference is positive, the PID controller decreases the phase adjustment signal, causing the upper bridge arm to conduct earlier, resulting in a relatively earlier voltage waveform and reducing the positive phase difference. When the phase difference is negative, the PID controller increases the phase adjustment signal, causing the upper bridge arm to conduct later, resulting in a relatively later voltage waveform and reducing the negative phase difference. Through this closed-loop control method, the time difference between the zero-crossing points of the current and voltage can be continuously corrected, and their phases are continuously adjusted to approximate each other, thereby effectively stabilizing and locking the frequency of the ultrasonic generator's output waveform.

[0031] The first timer is also used to determine the period of the current zero-crossing signal; the second timer is also used to set the period of the drive signal of the upper tube of the first bridge arm and the period of the drive signal of the lower tube of the first bridge arm to half the period of the current zero-crossing signal, based on the period of the current zero-crossing signal.

[0032] In one example, the first timer acts as the output detection module of the ultrasonic generator, acquiring the current zero-crossing signal and calculating its period. This is because the current zero-crossing signal reflects the oscillation frequency of the generator. The second timer acts as the drive signal generation module, which needs to set the period of the bridge arm drive waveform based on the detected current zero-crossing period. According to the full-bridge drive principle, the upper and lower bridge arms alternately conduct for one cycle to form a sine wave with a complete oscillation cycle. Therefore, the conduction periods of both the upper and lower bridge arms should be half of the current zero-crossing period. In this way, the second timer can set the drive period of both bridge arms to half of the current zero-crossing period based on the current zero-crossing period fed back by the first timer.

[0033] Through this coordination, the first timer completes signal detection and feedback, while the second timer completes the corresponding drive generation. The collaboration between the two ensures the synchronization and consistency between the drive signal and the generator output signal, thereby achieving stable frequency tracking and control of the ultrasonic generator.

[0034] like Figure 2 As shown, Figure 2 This is a schematic diagram of another adjustment device for an ultrasonic generator provided in an embodiment of this application.

[0035] The device also includes an analog-to-digital converter (ADC), a processor, and a third timer. The processor is connected to the ADC and the second timer, respectively, and the third timer is connected to the second timer. The ADC is used to acquire the DC current signal and DC voltage signal of the ultrasonic generator and perform analog-to-digital conversion to obtain the current amplitude and voltage amplitude of the ultrasonic generator. The processor is used to calculate the output power of the ultrasonic generator based on the current amplitude and voltage amplitude, and generate a power adjustment signal based on the output power of the ultrasonic generator and output it to the second timer. The third timer is used to generate a drive signal for the upper tube of the second bridge arm and a drive signal for the lower tube of the second bridge arm of the ultrasonic generator based on the power adjustment signal, so as to reduce the difference between the output power of the ultrasonic generator and the set power.

[0036] In one example, to achieve closed-loop control and stable tracking of the ultrasonic generator's output power, this scheme incorporates an analog-to-digital converter (ADC), a processor, and a third timer to form a control loop. The ADC acquires analog signals of the generator's current and voltage in real time, converts them into digital quantities, and transmits them to the processor. The processor calculates the real-time power and compares it with the set value, generating a power control signal. The third timer adjusts the drive waveform of the second bridge arm accordingly based on this power control signal to change the generator's output power. Through the coordinated operation of this digital closed-loop control process, the generator's output power can be continuously monitored, and deviations can be corrected in a timely manner to ensure that the power is stably locked at the set value, effectively suppressing drift caused by load changes and improving the stability and welding quality of the ultrasonic welding process.

[0037] The processor is configured to, when the output power of the ultrasonic generator is greater than the set power, decrease the value of the power adjustment signal to increase the phase offset between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube; and when the output power of the ultrasonic generator is less than the set power, increase the value of the power adjustment signal to decrease the phase offset between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube.

[0038] In one example, the processor is the core actuator of the power closed-loop control. It monitors the output power of the ultrasonic generator in real time. When it detects a power deviation from the set value, it generates a corresponding power adjustment control signal. This signal decreases when the power is too high and increases when the power is too low, then is transmitted to the third timer. The third timer adjusts the conduction time of the upper and lower tubes of the second bridge arm according to the magnitude and sign of the control signal, thereby changing the phase difference between the upper and lower bridge arms and controlling the generator's output power. If the power is too high, the phase difference is decreased to reduce the power; if the power is too low, the phase difference is increased to increase the power. Through this complete digital closed-loop control process, the processor can detect power deviations in real time and provide corresponding control, dynamically adjusting the output power to stably track the set value, thus enhancing the performance of the ultrasonic generator.

[0039] like Figure 2 As shown, the third timer is connected to the first timer; the third timer is used to generate the drive signal of the upper tube of the second bridge arm of the ultrasonic generator and the drive signal of the lower tube of the second bridge arm of the ultrasonic generator according to the adjustment signal, so as to reduce the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.

[0040] In one example, a third timer is connected to the first timer to obtain real-time phase difference detection information. When a positive phase difference is detected between the current and voltage signals, the third timer advances the phase of the drive waveform of the second bridge arm transistor; when a negative phase difference is detected, the third timer delays the phase of the drive waveform of the second bridge arm transistor. Through this precise adjustment of the phase of the second bridge arm drive waveform, the third timer can dynamically change the phase of the ultrasonic generator output waveform according to the feedback control of the first timer, continuously reducing and correcting the time difference between the zero-crossing points of the current and voltage, making the phase offset of the output signal approach zero, effectively improving the output signal quality and generator performance. Therefore, in this scheme, the third timer plays a closed-loop control role in conjunction with the first timer, jointly responsible for eliminating phase deviation and ensuring accurate frequency tracking.

[0041] The third timer is also used to set the period of the drive signal of the upper tube of the second bridge arm and the period of the drive signal of the lower tube of the second bridge arm to half the period of the current zero-crossing signal, based on the period of the current zero-crossing signal.

[0042] In one example, the third timer needs to be set to synchronize the second bridge arm drive signal period with the current signal to avoid generator detuning. Specifically, the third timer is connected to the first timer to obtain the accurate period of the current zero-crossing signal. Then, the drive waveform periods of both the upper and lower pipes of the second bridge arm are set to half the period of the current zero-crossing signal. In this way, the drive period of the second bridge arm is strictly equal to one period of the current signal. Through this period synchronization setting, it can be ensured that the output waveform of the second bridge arm is synchronized with the resonant current signal of the generator, effectively avoiding generator detuning and ensuring accurate and stable tracking of the output frequency. Therefore, the third timer, in conjunction with the first timer in setting the second bridge arm drive waveform period, forms a dual closed-loop control of the output frequency, jointly improving the control accuracy of the ultrasonic generator's frequency stability.

[0043] like Figure 3 As shown, Figure 3 This is a schematic diagram of another adjustment device for an ultrasonic generator provided in an embodiment of this application.

[0044] The device also includes a detection module, which is connected to the ultrasonic generator, the first timer, and the analog-to-digital converter. The detection module is used to acquire and detect the current output signal of the ultrasonic generator to obtain the current zero-crossing signal and the current DC signal of the ultrasonic generator, and to acquire the voltage output signal of the ultrasonic generator to obtain the voltage zero-crossing signal and the voltage DC signal of the ultrasonic generator.

[0045] In one example, the detection module is connected to the generator output to acquire various necessary output signals as information input for closed-loop control. Specifically, the detection module detects the current output signal, obtaining the zero-crossing signal and DC sample value; simultaneously, it detects the voltage output signal, obtaining the zero-crossing signal and DC sample value. After obtaining these signals, key parameters such as the generator's output frequency, output amplitude, and output power can be calculated, providing control input for subsequent devices such as PID controllers and timers to achieve closed-loop control and stable tracking of the generator's frequency, phase, and amplitude. Therefore, signal acquisition by the detection module is the first step in the entire stable control scheme and the foundation for achieving closed-loop control. By acquiring the necessary information, each component performs precise control based on these signals, ultimately achieving precise and stable output from the ultrasonic generator.

[0046] The ultrasonic generator includes a first bridge arm upper tube, a first bridge arm lower tube, a second bridge arm upper tube, a second bridge arm lower tube, and an ultrasonic generator adjustment device. The first end of the first bridge arm upper tube is connected to the first end of the second bridge arm upper tube. The second end of the first bridge arm upper tube is connected to the first end of the first bridge arm lower tube and serves as the first output end of the ultrasonic generator. The second end of the first bridge arm upper tube is connected to the first end of the first bridge arm lower tube and serves as the second output end of the ultrasonic generator. The second end of the first bridge arm lower tube is connected to the second end of the second bridge arm lower tube.

[0047] In one example, the ultrasonic generator includes an upper bridge arm and a lower bridge arm. The upper bridge arm comprises a first upper tube and a second upper tube, and the lower bridge arm comprises a first lower tube and a second lower tube. One end of the first upper tube is connected to one end of the second upper tube, forming a cross; its other end is connected to one end of the first lower tube, serving as the generator's first output terminal. The other end of the first lower tube is connected to the corresponding end of the second lower tube, forming an H-shaped bridge arm. Thus, when the upper and lower bridge arms are alternately conducting, AC signals can be output from both output terminals, thereby generating ultrasonic waves. The advantage of using an H-bridge topology is that it allows for AC signal output using four tubes, eliminating the need for an additional transformer and simplifying the circuit. The ultrasonic generator using an H-bridge topology can alternately utilize two tubes to output AC signals, simplifying the circuit structure.

[0048] like Figure 4 As shown, Figure 4 This is a structural schematic diagram of an ultrasonic welding device provided in an embodiment of this application.

[0049] The equipment includes a welding head, an amplitude transformer, a transducer, and an ultrasonic generator. The transducer is electrically connected to the ultrasonic generator, and the amplitude transformer is mechanically connected to both the transducer and the welding head.

[0050] Specifically, the equipment includes an ultrasonic generator as the signal source, and three transmission components: a transducer, an amplitude transformer, and a welding head. The transducer is electrically connected to the ultrasonic generator, and its function is to convert the electrical signal into mechanical vibration. The amplitude transformer is mechanically connected to the transducer, and its function is to amplify the amplitude of the mechanical vibration. The welding head is mechanically connected to the amplitude transformer and directly contacts the workpiece for welding. Through this electromechanical-mechanical conversion and transmission, the high-frequency electrical signal from the ultrasonic generator is gradually amplified, ultimately becoming a large-amplitude mechanical vibration sufficient for welding, which is then output to the welding head. In this way, the ultrasonic signal can be efficiently converted from electrical to mechanical signals and amplified to the welding head through this connection method, achieving ultrasonic welding.

[0051] It should be noted that the above embodiments of the apparatus are only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the apparatus and method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0052] The foregoing description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Other embodiments of this disclosure will be readily apparent to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described herein. The specification and embodiments are to be considered exemplary only.

Claims

1. An ultrasonic generator adjustment device, characterized in that, The device includes: a first timer, a PID controller, and a second timer, wherein the PID controller is connected to the first timer, and the second timer is connected to the first timer; The first timer is used to acquire the current zero-crossing signal and the voltage zero-crossing signal of the ultrasonic generator, and to determine the phase offset of the current zero-crossing signal and the voltage zero-crossing signal. The reset port of the first timer is used to receive the current zero-crossing signal. The PID controller is used to generate a phase adjustment signal and output it to the first timer based on the magnitude of the phase offset between the current zero-crossing signal and the voltage zero-crossing signal. The second timer is used to generate a drive signal for the upper tube of the first bridge arm of the ultrasonic generator and a drive signal for the lower tube of the first bridge arm of the ultrasonic generator according to the adjustment signal, so as to reduce the phase shift of the current zero-crossing signal and the voltage zero-crossing signal. The PID controller is used to decrease the value of the phase adjustment signal when the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is greater than 0, so as to increase the phase offset between the drive signal of the first bridge arm transistor and the current zero-crossing signal. When the phase offset between the current zero-crossing signal and the voltage zero-crossing signal is less than 0, the value of the phase adjustment signal is increased to reduce the phase offset between the drive signal of the first bridge arm upper transistor and the current zero-crossing signal. The first timer is also used to determine the period of the current zero-crossing signal; The second timer is further configured to set the period of the drive signal of the upper tube of the first bridge arm and the period of the drive signal of the lower tube of the first bridge arm to half the period of the current zero-crossing signal, based on the period of the current zero-crossing signal. The device further includes an analog-to-digital converter, a processor, and a third timer. The processor is connected to the analog-to-digital converter and the second timer, and the third timer is connected to the second timer. The analog-to-digital converter is used to acquire the DC current signal and DC voltage signal of the ultrasonic generator and perform analog-to-digital conversion to obtain the current amplitude and voltage amplitude of the ultrasonic generator; The processor is configured to calculate the output power of the ultrasonic generator based on the current amplitude and the voltage amplitude, and generate a power adjustment signal based on the output power of the ultrasonic generator and output it to the second timer. The third timer is used to generate a drive signal for the upper tube of the second bridge arm of the ultrasonic generator and a drive signal for the lower tube of the second bridge arm of the ultrasonic generator according to the power adjustment signal, so as to reduce the difference between the output power of the ultrasonic generator and the set power.

2. The ultrasonic generator adjustment device according to claim 1, characterized in that, The processor is used for, When the output power of the ultrasonic generator is greater than the set power, the value of the power adjustment signal is reduced to increase the phase offset between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube. When the output power of the ultrasonic generator is less than the set power, the value of the power adjustment signal is increased to reduce the phase offset between the drive signal of the second bridge arm upper tube and the drive signal of the second bridge arm upper tube.

3. The ultrasonic generator adjustment device according to claim 1, characterized in that, The third timer is connected to the first timer; the third timer is used to generate a drive signal for the upper tube of the second bridge arm of the ultrasonic generator and a drive signal for the lower tube of the second bridge arm of the ultrasonic generator according to the adjustment signal, so as to reduce the phase offset of the current zero-crossing signal and the voltage zero-crossing signal.

4. The ultrasonic generator adjustment device according to any one of claims 1-3, characterized in that, The third timer is also used to set the period of the drive signal of the upper tube of the second bridge arm and the period of the drive signal of the lower tube of the second bridge arm to half the period of the current zero-crossing signal, based on the period of the current zero-crossing signal.

5. The ultrasonic generator adjustment device according to claim 1, characterized in that, The device further includes a detection module, which is connected to the ultrasonic generator, the first timer and the analog-to-digital converter respectively. The detection module is used to acquire and detect the current output signal of the ultrasonic generator to obtain the current zero-crossing signal and the current DC signal of the ultrasonic generator, and to acquire the voltage zero-crossing signal and the voltage DC signal of the ultrasonic generator.

6. An ultrasonic generator, characterized in that, The ultrasonic generator includes a first upper bridge tube, a first lower bridge tube, a second upper bridge tube, a second lower bridge tube, and an ultrasonic generator adjustment device as described in any one of claims 1-5. The first end of the first upper bridge tube is connected to the first end of the second upper bridge tube, the second end of the first upper bridge tube is connected to the first end of the first lower bridge tube and serves as the first output end of the ultrasonic generator, the second end of the first upper bridge tube is connected to the first end of the first lower bridge tube and serves as the second output end of the ultrasonic generator, and the second end of the first lower bridge tube is connected to the second end of the second lower bridge tube.

7. An ultrasonic welding device, characterized in that, The device includes a welding head, an amplitude transformer, a transducer, and an ultrasonic generator as described in claim 6, wherein the transducer is electrically connected to the ultrasonic generator, and the amplitude transformer is mechanically connected to both the transducer and the welding head.

Images