Ultrasonic generator based on frequency real-time scanning and tracking and working method

Abstract

The invention discloses an ultrasonic generator based on frequency real-time scanning and tracking and a working method.The ultrasonic generator works when the frequency of the ultrasonic generator is tracked at a resonance point with the minimum current, micro-vibration of an ultrasonic transducer is more uniform, the machining quality can reach the best when the ultrasonic generator is matched with an ultrasonic machining tool to machine a workpiece, and the machining efficiency is improved. Compared with other resonance points, the working current acting on the transducer is smaller, the ultrasonic transducer is smaller in loss and less in heat emission, and the continuous working time is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrasonic waves, in particular to the technical field of an ultrasonic wave generator and a working method based on real-time frequency scanning and tracking. Background Art

[0002] With technological advancements, the complexity of industrial products continues to rise, pushing the demands for machining precision and efficiency to unprecedented levels. Traditional machine tools are gradually showing their limitations when processing workpieces made of specialized materials and complex shapes. For example, machining high-hardness materials is challenging, as high cutting forces can lead to severe tool wear. Brittle materials are also prone to cracking and breaking during machining.

[0003] At the same time, the application of ultrasonic technology in machining is gaining increasing attention. Ultrasonic machining utilizes the energy of ultrasonic vibrations to effectively reduce cutting forces, minimize tool wear, and improve machining quality. It is particularly suitable for machining hard and brittle materials, achieving high-precision, low-damage machining results.

[0004] During ultrasonic machining, the ultrasonic generator, which generates and drives the ultrasonic signal, is a very important component of the system. Currently, there are many types of ultrasonic generators on the market, which can be broadly divided into analog signal generators and digital signal generators.

[0005] Ultrasonic analog signal generators are generally used in high-power applications, such as cleaning and welding, where load fluctuations are minimal. By integrating the transducer into the circuit as a component of the signal generator, ultrasonic analog signal generators offer the advantage of real-time frequency tracking. However, their major drawback is their narrow applicable frequency range and the high frequency matching requirements for the transducer. Different transducer types require ultrasonic generators with different frequency ranges.

[0006] Digital signal generators overcome the aforementioned drawback of a narrow frequency range, making them suitable for applications with lower power and varying resonant frequencies. Since the transducer passively receives ultrasonic signals, frequency tracking is not directly related to the transducer itself. Therefore, they can be widely used in various relatively low-power environments. Their final wireless transmission capability offers significant advantages for installation in processing tools unsuitable for wired transmission.

[0007] For low-power transducers used for processing hard and brittle materials, in actual operation, conventional ultrasonic generators used for welding or cleaning all operate at the resonance point where the current is maximum. At this point, the resonant circuit impedance is minimum, so the current reaches its maximum or peak value. When operating at this point, due to the high current, the power consumption of the transducer is also high, inevitably causing heating and excessive losses. Summary of the Invention

[0008] The purpose of the present invention is to solve the problems in the prior art and to propose an ultrasonic generator and working method based on real-time frequency scanning and tracking. The micro-vibration of the ultrasonic transducer is more uniform, the working current acting on the transducer is smaller, the ultrasonic transducer has less loss and heat, and the continuous working time is extended.

[0009] To achieve the above object, the present invention proposes an ultrasonic generator operating method based on real-time frequency scanning and tracking, comprising the following steps: Perform a wide frequency sweep when the ultrasonic generator is unloaded, record the current changes when the frequency changes, find the frequency point when the current is minimum, and record the frequency. After the frequency sweep is completed, preliminarily confirm that the generator is working at this frequency point, which is used as the initial working frequency point. After starting work, since the resonant frequency will change due to changes in load, the actual current value of the ultrasonic generator is monitored at this time. If a change is found, a narrow range frequency scan is performed near the initial operating frequency point to find the frequency point with the minimum current value again. This is the new resonant frequency point; thereafter, the current is continuously monitored based on this frequency. If there is any change, a narrower frequency scan is performed to find the latest resonant point frequency; This method is used to continuously track so that the generator always operates at the resonance point.

[0010] Preferably, if the resonance point cannot be found during the continuous monitoring and scanning process, an alarm is issued and an early warning signal is output to the outside world at the same time as the alarm.

[0011] Preferably, the output of the warning signal to the outside world includes a 24V level mode or a 485 communication mode, and communication is carried out with a processing machine controlled by a PLC through the 24V level mode or the 485 communication mode to ensure that when the ultrasonic system cannot operate in a resonant state after frequency tracking fails due to external reasons, appropriate processing is performed on the feed amount of the processing machine.

[0012] Preferably, a wide range frequency scan is performed when the ultrasonic generator is unloaded, and the change in current when the frequency changes is recorded. A frequency point at which the current is maximum is found as the first resonance point, and then a frequency point at which the current is maximum is found again as the third resonance point. A frequency point at which the current is minimum is found between the first resonance point and the third resonance point, and this frequency is recorded as the second resonance point. The ultrasonic generator operates at the second resonance point.

[0013] Another object of the present invention is to provide an ultrasonic generator based on real-time frequency scanning and tracking, comprising: The power supply module is used to convert the mains electricity into a low-voltage stable driving power supply, which is provided to the linear power amplifier module for driving the ultrasonic signal loaded on the transducer; Linear power amplifier module, used for power adjustment; an isolation transformer connected to the linear power amplifier module; a transducer, connected to the isolation transformer, for converting electrical energy into ultrasonic vibrations; The signal generation module is composed of a single-chip microcomputer and a sine wave generation module. The single-chip microcomputer controls the sine wave generation module and digitally adjusts the frequency and amplitude of the sine wave signal. The signal is amplified by the linear power amplifier module and then drives the transducer through an isolation transformer. The current sampling module is provided on the circuit loop between the power supply module and the linear power amplifier module, and is used to collect the circuit current and transmit the collected information to the signal generating module.

[0014] Preferably, the power module outputs a 24V DC power supply.

[0015] Preferably, it further includes a control display module connected to the signal generating module, for providing a control interface to adjust the amplitude of the signal generated by the signal generating module.

[0016] The beneficial effects of the ultrasonic generator and working method based on real-time frequency scanning and tracking of the present invention are as follows: the frequency tracking of the ultrasonic generator of the present invention works at the resonance point with the minimum current, the micro-vibration of the ultrasonic transducer is more uniform, and the processing quality can be optimized when the workpiece is processed in conjunction with an ultrasonic processing tool. Compared with other resonance points, the working current acting on the transducer is smaller, the ultrasonic transducer has smaller loss and less heat, and the continuous working time is extended.

[0017] The features and advantages of the present invention will be described in detail through embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of an ultrasonic generator based on real-time frequency scanning and tracking of the present invention.

[0019] Figure 2 It is a waveform curve showing the relationship between the current value and frequency of the power output of the ultrasonic generator on the transducer used for processing hard and brittle materials.

[0020] in: 1-Power supply module; 2-Linear power amplifier module; 3-Transducer; 4-Signal generation module; 5-Isolation transformer; 6-Current sampling module; 7-Control display module DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and examples. However, it should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the present invention.

[0022] In the description of the present invention, it should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0023] In the description of the present invention, it should be noted that the terms "center", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0024] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0025] The ultrasonic generator is used for processing hard and brittle materials. The relationship between the current value and frequency of its power output is shown in the waveform curve of the instruction manual. Figure 2 As shown in the accompanying drawings of the specification. Figure 2As shown, for a low-power transducer used for processing hard and brittle materials, there will be three resonance points during actual operation, among which the first resonance point and the third resonance point are maximum values, and the second resonance point is the minimum value. Example

[0026] The present invention provides an ultrasonic generator and a working method based on real-time frequency scanning and tracking, comprising the following steps: Perform a wide frequency sweep when the ultrasonic generator is unloaded, record the current changes when the frequency changes, find the frequency point when the current is minimum, and record the frequency. After the frequency sweep is completed, preliminarily confirm that the generator is working at this frequency point, which is used as the initial working frequency point. After starting work, since the resonant frequency will change due to changes in the load, the actual current value of the ultrasonic generator is monitored at this time. If a change is found, a narrow range frequency scan is performed near the initial operating frequency point to find the frequency point with the minimum current value again. This is the new resonant frequency point; thereafter, the current is continuously monitored based on this frequency. If there is a change, a narrower frequency scan is performed to find the latest resonant point frequency; this method is used for continuous tracking so that the generator always operates at the resonant point. When the ultrasonic generator frequency is tracked at the resonant point with the minimum current in this embodiment, the micro-vibration of the ultrasonic transducer is more uniform, and the processing quality can be optimized when the ultrasonic machining tool is used to process the workpiece. Compared with other resonant points, the working current acting on the transducer is smaller, the ultrasonic transducer has less loss and heat, and the continuous working time is extended.

[0027] When this method is operating, theoretically, the loop impedance reaches its maximum value and the current sampling value reaches its minimum value. In this resonant mode, the quality of the ultrasonic waveform acting on the ultrasonic transducer is better than that at the other two maximum values. In this mode, although the ultrasonic micro-vibration of the transducer is slightly smaller than that at the other two resonance points, its micro-vibration is more uniform, resulting in optimal processing quality. If you want to achieve the same vibration amplitude as the first and third resonance points, you can solve this problem by increasing the ultrasonic amplitude. Because the size of the ultrasonic amplitude has no direct relationship with the resonant frequency during actual use. Example 1

[0028] On the basis of the above, an alarm output function for frequency tracking failure has been added. If the resonance point cannot be found during the continuous monitoring and scanning process, an alarm will be issued and a warning signal will be output to the outside world at the same time. There are two specific methods: one is 24V level mode and the other is 485 communication mode. These two methods are used to communicate with popular PLC-controlled processing machines to ensure that if the ultrasonic system cannot operate in a resonant state due to external reasons after frequency tracking fails, the processing machine feed rate will be appropriately processed to ensure the safety of processing. When used in conjunction with ultrasonic processing machines, the alarm output function for frequency tracking failure can ensure that if the ultrasonic system cannot operate in a resonant state due to external reasons after frequency tracking fails, the processing machine feed rate will be appropriately processed to ensure the safety of processing tools and workpieces. Example 2

[0029] See Figure 1 The present invention discloses an ultrasonic generator based on real-time frequency scanning and tracking, comprising a power supply module 1, a linear power amplifier module 2, an isolation transformer 5, and a transducer 3, which are connected in sequence. The power supply module 1, the linear power amplifier module 2, the isolation transformer 5, and the transducer 3 form a resonant circuit. A current sampling module 6 is provided between the power supply module 1 and the linear power amplifier module 2 in the resonant circuit, for collecting circuit current and transmitting the collected information to the signal generating module 4. The signal generating module 4 is connected to the linear power amplifier module 2. A control and display module 7 is also provided, connected to the signal generating module 4, for providing an interface for controlling the signal generating module 4. In this embodiment, the ultrasonic generator power supply module 1 uses a standard ±24V power supply voltage to provide the linear power amplifier module 2 for driving the ultrasonic signal applied to the transducer 3. The +24V voltage is linearly stepped down and stabilized to produce a +5V power supply for the signal generating module 4 and the control and display module 7. Signal generator module 4 uses a single-chip microcomputer to control the sine wave generator module, digitally adjusting the frequency and amplitude of the sine wave signal. This signal is amplified by linear power amplifier module 2 for amplitude and power before passing through isolation transformer 5 to drive the transducer. The amplitude of the generated signal can be adjusted via control and display module 7, and the frequency is preset and adjusted during operation based on the current sampling value. If the frequency cannot be adjusted to the resonant point, that is, if the frequency cannot be adjusted to the minimum current value, an alarm signal is output.

[0030] The standard parts used in this application document can all be purchased from the market, and the specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the existing technology. The electric slide rail slide, cylinder, welding machine, electric telescopic rod and internal components of the controller all adopt conventional models in the existing technology, and their internal structure belongs to the existing technology structure. Workers can complete normal operation of them according to the existing technical manual. In addition, the circuit connection adopts the conventional connection method in the existing technology, and no detailed description is given here.

[0031] It should be noted that although the above embodiments have been described herein, this does not limit the scope of patent protection of the present invention. Therefore, based on the innovative concept of the present invention, changes and modifications to the embodiments described herein, or equivalent structural or equivalent process transformations made using the contents of the present invention's description and drawings, and direct or indirect application of the above technical solutions to other related technical fields, are all included in the scope of protection of the present invention's patent.

Claims

1. A method for operating an ultrasonic generator based on real-time frequency scanning and tracking, characterized in that: The following steps are involved: Perform a wide range frequency scan when the ultrasonic generator is unloaded, record the change in current when the frequency changes, find the frequency point when the current is minimum, and record the frequency. After the frequency scan is completed, preliminarily confirm that the generator is working at this frequency point as the initial working frequency point; After starting work, since the resonant frequency will change due to changes in load, the actual current value of the ultrasonic generator is monitored at this time. After the change is found, a narrow range frequency scan is performed near the initial working frequency point to find the frequency point with the minimum current value again. This is the new resonant frequency point; thereafter, the current is continuously monitored based on this frequency. If there is a change, a narrower frequency scan is performed to find the latest resonant point frequency; This method is used to continuously track so that the generator always operates at the resonance point.

2. The ultrasonic generator working method based on real-time frequency scanning and tracking as claimed in claim 1, characterized in that: If the resonance point cannot be found during the continuous monitoring and scanning process, an alarm will be issued and a warning signal will be output to the outside world at the same time.

3. The ultrasonic generator working method based on real-time frequency scanning and tracking as claimed in claim 2, characterized in that: The output of the warning signal to the outside world includes a 24V level mode or a 485 communication mode, and communication with the processing machine controlled by the PLC is carried out through the 24V level mode or the 485 communication mode to ensure that when the ultrasonic system cannot work in a resonant state after frequency tracking fails due to external reasons, appropriate processing is performed on the feed amount of the processing machine.

4. The ultrasonic generator working method based on real-time frequency scanning and tracking as claimed in claim 1, characterized in that: Perform a wide range frequency scan when the ultrasonic generator is unloaded, record the change in current when the frequency changes, find a frequency point when the current is maximum as the first resonance point, then find another frequency point when the current is maximum as the third resonance point, find the frequency point when the current is minimum between the first resonance point and the third resonance point, record this frequency as the second resonance point, and the ultrasonic generator operates at the second resonance point.

5. An ultrasonic generator used in the ultrasonic generator working method based on frequency real-time scanning and tracking as described in any one of claims 1 to 4, characterized in that: include: A power supply module (1) is used to convert the mains electricity into a low-voltage stable driving power supply, which is provided to the linear power amplifier module (2) for driving the ultrasonic signal loaded on the transducer (3); A linear power amplifier module (2), used for adjusting power; An isolation transformer (5) connected to the linear power amplifier module (2); A transducer (3), connected to the isolation transformer (5), for converting electrical energy into ultrasonic vibrations; The signal generating module (4) is composed of a single chip microcomputer and a sine wave generating module. The single chip microcomputer controls the sine wave generating module and adjusts the frequency and amplitude of the sine wave signal in a digital manner. The signal is amplified in amplitude and power by the linear power amplifier module (2) and then drives the transducer (3) to work by means of an isolation transformer (5); A current sampling module (6) is provided on the circuit loop between the power module (1) and the linear power amplifier module (2), and is used to collect the magnitude of the circuit current and transmit the collected information to the signal generating module (4).

6. The ultrasonic generator based on real-time frequency scanning and tracking as claimed in claim 5, characterized in that: The power module (1) outputs a 24V DC power supply.

7. The ultrasonic generator based on real-time frequency scanning and tracking as claimed in claim 5, characterized in that: It also comprises a control display module (7) connected to the signal generating module (4) and used to provide a control interface and adjust the amplitude of the signal generated by the signal generating module (4).

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