Push-pull type ultrasonic vibration system and method based on wavelength adjustment

Abstract

The invention discloses a push-pull type ultrasonic vibration system and method based on wavelength adjustment. The system comprises an ultrasonic generator, a transducer, a vibration transmission component and a tool head. The total acoustic length of the vibration transmission component and the tool head is designed as follows: the working end face of the tool head is positioned at the antinode of a standing wave, and the vibration displacement directions of the two sides are opposite. This can be achieved by increasing half wavelength on the left or right side of the working end face, or decreasing half wavelength on the left or right side. The push-pull effect is generated only through mechanical structure wavelength design and by means of standing wave characteristics of ultrasonic waves, a reverse polarization transducer or a complex anti-phase electric signal does not need to be used, the performance requirement for core components is remarkably lowered, the system structure and control are simplified, and reliability and economical efficiency are improved.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic application technology, specifically to a vibration system for ultrasonic welding or cutting, and in particular to a novel vibration structure that achieves a push-pull effect through structural wavelength design. Background Technology

[0002] In ultrasonic applications, push-pull structures are often used to obtain larger output amplitudes. Traditional push-pull structures mainly rely on the coordinated operation of two vibration sources with opposite phases. There are two main ways to achieve this: one is to manufacture two piezoelectric ceramic transducers with opposite polarization directions, which generate reverse vibrations under the same electrical signal excitation; the other is to use two identical transducers, but driven by two reverse electrical signals with a phase difference of 180° provided by an ultrasonic generator.

[0003] However, the aforementioned traditional methods have significant drawbacks. Method 1 requires extremely high consistency between the two transducers in terms of materials, dimensions, and performance; otherwise, it will lead to vibration imbalance, affecting output efficiency and system stability, and the assembly process is complex. Method 2 places extremely high demands on the output stability of the ultrasonic generator and the consistency of the two signals, increasing the complexity and cost of circuit design.

[0004] Therefore, the industry urgently needs a new solution that can achieve stable and efficient push-pull vibration without relying on special transducer assembly or complex electrical excitation methods.

[0005] Invention content This invention aims to overcome the shortcomings of existing technologies and provide a push-pull ultrasonic vibration system and method based on wavelength adjustment. This solution, by simply designing the wavelength of the vibration system itself, such as the amplitude transformer and tool head, and utilizing the standing wave characteristics of ultrasound, can naturally generate push-pull vibrations with opposite directions and synergistic effects at a specified location, such as a welding head, thereby reducing the stringent requirements on transducers and generators.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A push-pull ultrasonic vibration system based on wavelength adjustment includes an ultrasonic generator, two transducers, a vibration transmission component, and a tool head. The transducers generate initial mechanical vibration under the excitation of a single-phase electrical signal provided by the ultrasonic generator. The vibration transmission component transmits the vibration to the tool head. The core improvement of the system lies in the fact that the combined structure of the vibration transmission component and the tool head is designed such that the working end face of the tool head is located at the antinode (maximum amplitude) of the longitudinal standing wave of the entire system, and the vibration displacement directions are opposite on both sides with this working end face as a symmetrical reference plane.

[0007] Specifically, there are two preferred implementation methods to achieve the above-mentioned structural design of "opposite vibration displacement directions on both sides": Implementation Method 1: Increase Wavelength. Using the working end face of the tool head as a reference, add half a wavelength of acoustic length to the vibration transmission path on its left or right side. This operation is equivalent to introducing an additional vibration nodal surface on the left or right side of the system, causing the vibration phase from the newly added nodal surface to the working end face of the tool head to be opposite to the vibration phase that the working end face should have in the original structure, thus naturally forming a push-pull relationship with the vibration on the right or left side of the system.

[0008] Implementation Method Two: Reduce Wavelength. Using the working end face of the tool head as a reference, reduce the acoustic length by half a wavelength along the vibration transmission path on its left or right side. This operation is equivalent to removing an original vibration nodal surface, causing the vibration phases on both sides of the working end face of the tool head to be directly opposite, thus forming a push-pull relationship.

[0009] The term "half wavelength" refers to half the wavelength of an ultrasonic wave as it propagates through the material that constitutes the vibration transmission component and the tool head.

[0010] The present invention also provides a method for achieving push-pull vibration based on wavelength adjustment, applied to the above-mentioned system, comprising the following steps: S1: Provides two in-phase transducers driven by an ultrasonic generator; S2: Design the total acoustic length of the vibration transmission path so that the working end face of the tool head is located at the antinode of the longitudinal vibration standing wave; S3: By adjusting the acoustic length on one side of the working end face, increasing or decreasing it by half a wavelength relative to the reference design, a push-pull vibration mode with opposite vibration displacement directions is formed on both sides of the working end face.

[0011] (III) Beneficial Effects Compared with the prior art, the advantages of the present invention are as follows: 1. Reduced requirements for transducer consistency: There is no need to use special transducers with opposite polarization directions; identical standardized transducers can be used, simplifying the procurement and assembly process and improving production efficiency and system reliability.

[0012] 2. Simplified ultrasonic generator design: Only a single or multiple standard electrical signals of the same phase are required, eliminating the need to generate and precisely control two highly stable electrical signals with opposite phases, which greatly reduces the circuit complexity and manufacturing cost of the generator.

[0013] 3. Improved system stability: The push-pull effect is determined by the inherent wavelength characteristics of the mechanical structure and is not affected by electrical parameter drift or minor differences in transducers, resulting in a more stable and reliable vibration mode.

[0014] 4. Maintains high performance: Through precise wavelength design, the working end face of the tool head is ensured to be located at the antinode of the wave with the largest amplitude, while obtaining the amplitude superposition advantage brought by the push-pull structure. The output capability is comparable to or even better than that of the traditional push-pull structure.

[0015] 5. Simple structure and easy to implement: Only wavelength calculation and structural modification are required in the design stage of traditional amplitude transformers or tool heads. No additional complex parts are needed, making it easy to implement and promote. Attached Figure Description

[0016] Figure 1 This is a structural diagram of an ultrasonic vibration system according to Embodiment 1 of the present invention (with an added half wavelength).

[0017] Figure 2 This is a schematic diagram of vibration displacement in Embodiment 1 of the present invention (with an added half wavelength).

[0018] Figure 3 This is a structural diagram of the ultrasonic vibration system according to Embodiment 2 (reducing half wavelength) of the present invention.

[0019] Figure 4 This is a schematic diagram of the vibration displacement in Embodiment 2 (reducing half wavelength) of the present invention.

[0020] (In the figure: 1-ultrasonic transducer (with sleeve), 2-full-wavelength amplitude transformer, 3-full-wavelength welding head, 4-half-wavelength amplitude transformer, N-nodal surface (zero displacement), A-antinode (maximum displacement), F-working end face of tool head, the arrow direction indicates the instantaneous vibration displacement direction) Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Example 1: Reference Figure 1 This embodiment employs a method of "adding half a wavelength on the left side." A standard transducer generates the initial vibration. The length of the vibration transmission component (such as the amplitude transformer) is designed to satisfy the following condition with the total length of the tool head: (Refer to...) Figure 2 With the working end face (F) of the tool head as the boundary, the acoustic path on its left side is extended by λ / 2 (half a wavelength) compared to a conventional single-vibration system design. This results in an additional nodal surface (N1) in the left region. Under unidirectional electrical signal excitation, the vibration is transmitted from the transducer and reverses direction after passing through the N1 nodal surface. Therefore, when reaching the working end face F, the vibration displacement direction on its left side (the left-hand arrow in the figure) is exactly opposite to the vibration displacement direction on its right side (the right-hand arrow in the figure). Point F itself is designed to be located at the antinode (A), where the amplitude is maximum, thus achieving efficient push-pull output.

[0023] Example 2: Reference Figure 3 This embodiment employs a "right-side half-wavelength reduction" method. The system also uses a standard transducer. (Refer to...) Figure 4 With the working end face (F) of the tool head as the boundary, the acoustic path on the right side is reduced by λ / 2 compared to the conventional design. This is equivalent to removing a desired nodal face on the right. In the design, point F is directly located at the antinode (A). Because the length on the right side is shortened by half a wavelength, the vibration phase of the region to the right of point F is automatically out of phase compared to the left side. Therefore, the vibration displacement directions to the left and right of point F also form opposite states (as shown by the arrows in the figure), realizing the push-pull effect.

[0024] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A wavelength-adjusted push-pull ultrasonic vibration system comprising an ultrasonic generator, two transducers, a vibration transmission member, and a tool head, characterized by: The combination of the vibration transmission component and the tool head has a total acoustic length designed such that the working end face of the tool head is located at the antinode of the longitudinal vibration standing wave of the whole system, and with the working end face as the symmetrical reference surface, the vibration displacement directions on both sides are opposite.

2. The system of claim 1, wherein, The "vibration displacement directions on both sides are opposite" is realized by one of the following ways: increasing the acoustic length by half a wavelength on the left or right side of the working end face of the tool head; or reducing the acoustic length by half a wavelength on the left or right side of the working end face of the tool head.

3. The system of claim 2, wherein, The "half a wavelength" refers to the half wavelength of the ultrasonic wave when propagating in the materials of the vibration transmission component and the tool head of the system.

4. The system according to any one of claims 1-3, characterized in that, The two transducers are the same type of transducers with the same polarization direction.

5. The system according to any of claims 1-3, characterized in that, The ultrasonic wave generator provides the same phase electric excitation signal to all transducers.

6. A method for adjusting the wavelength-based realization of push-pull oscillation, applied in a system according to any one of claims 1-5, characterized in that, The method comprises the steps of: S1: designing the total acoustic length of the vibration transmission path such that the working end face of the tool head is located at the antinode of the longitudinal vibration standing wave; S2: adjusting the acoustic length on one side of the working end face to increase or decrease half a wavelength relative to the reference design, so as to form a push-pull vibration mode with opposite vibration displacement directions on both sides of the working end face.

7. The method of claim 6, wherein, The adjustment mode is to increase half a wavelength to the left or right side of the working end face of the tool head, or to reduce half a wavelength to the left or right side of the working end face of the tool head.

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