Ultrasonic welding fixing method and structure based on vibration extreme point

Abstract

This invention belongs to the field of ultrasonic welding technology, specifically relating to an ultrasonic welding fixing method and structure based on vibration extreme points. The method includes the following steps: S1, performing deformation amplitude analysis on the surface of the welding head and selecting the surface farthest from the welding surface as the support connection surface; S2, integrally molding the support tool with the welding head, and through system vibration performance analysis of the welding head with the added support tool, designing a support structure with a smaller amplitude on the corresponding side of the welding head; S3, designing a support base that matches the support tool based on the performance analysis, and implementing a lightweight design for the bottom and sides of the support base. This invention, combined with actual welding requirements, selects a suitable position on the side of the welding head to add the support tool, and through comprehensive analysis and judgment, optimizes the performance of the welding system to the greatest extent; in addition, through the improved design of the support base, the overall performance of the welding system can be further improved.

Description

Technical Field

[0001] This invention belongs to the field of ultrasonic welding technology, specifically relating to an ultrasonic welding fixing method and structure based on vibration extreme points. Background Technology

[0002] The most common fixing points for ultrasonic welding systems are the amplitude transformer or the welding head. Proper fixing ensures optimal dynamic performance and maximizes vibration isolation. For amplitude transformers, composite cross-section amplitude transformers can have a section designed as rectangular, with the amplitude transformer node positioned there. A support ring is then inserted and fixed into this section. For single-section amplitude transformers without a rectangular cross-section, since the support ring cannot be fitted, a flange for fixing is typically machined at the node during manufacturing. The fixing method for the welding head can refer to that of the amplitude transformer. For large welding heads, adding a fixing ring is also difficult; therefore, the welding head and a dedicated support tool can be manufactured as a single unit. After selecting the fixing point, a choice can be made between tight and loose connections. However, existing technologies still have the following defects and shortcomings:

[0003] 1. Loose connections and low rigidity of the welding system may cause changes in the position of the weld head under external loads, affecting the welding quality.

[0004] 2. Tight connection: After fixing using this method, finite element calculations or experimental verification are required to evaluate the vibration characteristics of the welding system and support tools. When designing the support, energy loss caused by large resonance of the support should be avoided.

[0005] 3. In the original design, the transducer housing and the support ring on the transducer were used as fixed positions, and bolts were used to firmly tighten the clamping device onto the frame. During the processing, the bolts often loosened, resulting in poor vibration isolation performance of the system's fixing scheme.

[0006] To address the aforementioned issues, it is essential to redesign a support tool at the welding head and employ a tight connection to secure the welding system. Furthermore, a new base needs to be designed for support, resulting in superior welding performance. Summary of the Invention

[0007] The purpose of this invention is to address the defects and shortcomings in the existing technology and to provide an ultrasonic welding and fixing method and structure based on vibration extreme points.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is: an ultrasonic welding and fixing method based on vibration extreme points, comprising the following steps:

[0009] S1. Perform deformation amplitude analysis on the surface of the welding head and select the surface far away from the welding surface as the supporting connection surface;

[0010] S2. The support tool and the welding head are integrally formed. By analyzing the system vibration performance of the welding head with the added support tool, a support structure with a small amplitude is designed on the corresponding side of the welding head.

[0011] S3. Design a support base that matches the support tool based on performance analysis, and carry out lightweight design on the bottom and sides of the support base.

[0012] Preferably, in step S1, the side of the welding head is selected as the supporting connection surface, and the first position K1 and the second position K2 are selected according to the overall deformation amplitude and longitudinal deformation amplitude of the side of the welding head.

[0013] Preferably, support tools are added at the first position K1 and the second position K2 respectively for amplitude analysis.

[0014] Preferably, the method for analyzing the system vibration performance in step S2 is as follows: after optimizing the Hypermesh mesh, perform finite element analysis, divide the appropriate mesh according to the model shape, or divide the elements according to the force and stress concentration, and after obtaining the element model, import it into ANSYS to establish a finite element model, assign materials, apply constraints according to actual conditions to analyze the modes, and compare the performance with that without support tools to analyze the impact of the maximum amplitude on the performance of the welding system.

[0015] Preferably, in step S3, the support base is designed according to the natural frequency of the support tool to ensure that the vibration of the welding system will not cause resonance of the support base.

[0016] Preferably, the material of the support base in step S3 is No. 45 steel.

[0017] An ultrasonic welding fixing structure based on vibration extreme points includes support tools symmetrically arranged on the left and right sides of the welding head, with the end of the support tool away from the welding head fixed to the support base by a pressure plate.

[0018] Preferably, the support tool includes a first connecting end and a second connecting end that are perpendicular to each other. The first connecting end is integrally designed with the welding head, and the front and rear sides of the second connecting end are respectively connected to a pressure plate and a support base.

[0019] Preferably, the pressure plate and the support base are detachably connected by bolts.

[0020] After adopting the above technical solution, the ultrasonic welding and fixing method and structure based on vibration extreme points provided by the present invention have the following beneficial effects:

[0021] This invention combines actual welding needs and adds support tools at appropriate positions on the side of the welding head. Through comprehensive analysis and judgment, the performance of the welding system is optimized to the greatest extent. In addition, the overall performance of the welding system can be further improved through the improved design of the support base. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the welding head structure in this invention;

[0023] Figure 2 This is a schematic diagram of the support tool structure in this invention;

[0024] Figure 3 This is a schematic diagram of the structure of the support base and welding assembly in this invention;

[0025] Figure 4 This is a schematic diagram of the deformation test of the welding head;

[0026] Figure 5 This is a schematic diagram showing the vibration of the welding head's side.

[0027] Figure 6 This is a diagram showing the placement of the support tools;

[0028] Figure 7 for Figure 6 Vibration performance test diagram of the welding head and the support tool when the support tool is placed at point K1;

[0029] Figure 8 for Figure 6 Vibration performance test diagram of the welding head and the support tool when the support tool is placed at point K2;

[0030] Figure 9 The diagram shows the vibration performance test results for the supporting base.

[0031] The components include: 1. Welding head; 2. Support tool; 3. Pressure plate; 4. Support base; 5. First connecting end; 6. Second connecting end; 7. Bolt. Detailed Implementation

[0032] The present invention will now be described more clearly and completely with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0033] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0034] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0035] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0036] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0037] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0038] like Figure 1-9 As shown, the present invention provides an ultrasonic welding and fixing method based on vibration extreme points, comprising the following steps:

[0039] S1. Perform deformation amplitude analysis on the surface of the welding head, select the surface away from the welding surface as the support connection surface. Specifically, select the side of the welding head as the support connection surface, and select the first position K1 and the second position K2 according to the overall deformation amplitude and longitudinal deformation amplitude of the side of the welding head. Add support tools at the first position K1 and the second position K2 respectively to perform amplitude analysis.

[0040] Adding support tools at K1 and K2 respectively, the maximum amplitude of the overall and longitudinal vibration at K1 is still around 30μm, and the maximum amplitude of the overall and longitudinal vibration at K2 is still around 31μm, and the position of the maximum amplitude is on the welding surface of the welding head. The support tool is located at the position of minimum amplitude of the welding head, and the amplitude distribution of the welding head after adding the support tool is almost unchanged. Therefore, adding support tools on the side has almost no impact on the performance of the welding system.

[0041] The maximum amplitude of the support tool added at K1 is 1.5 μm, and it is located near the second connection end. The average amplitude of its overall amplitude is below 1 μm. During the vibration, the maximum stress of the support tool is about 19 MPa. The longitudinal amplitude of the support reaction force at the first connection end of the support tool is 44.506 N, the lateral amplitude is 69.561 N, and the vertical amplitude is 0.21645 N.

[0042] The maximum amplitude of the support tool added at K2 reached about 3μm and was located near the second connection end. The maximum stress of the support tool was about 36.8MPa. The longitudinal amplitude of the support reaction force at the first connection end of the support tool at point K2 reached 126.13N, the lateral amplitude was 175.76N, and the vertical amplitude was 0.21191N.

[0043] In conclusion, placing a support tool at point K1 is a better choice compared to K2.

[0044] S2. The support tool and welding head are integrally formed. The system vibration performance of the welding head with the added support tool is analyzed. A support structure with a small amplitude is designed on the side of the corresponding welding head. Specifically, after optimization of the Hypermesh mesh, finite element analysis is performed. The appropriate mesh is divided according to the shape of the model, or the elements are divided according to the force and stress concentration. After obtaining the element model, it is imported into ANSYS to establish a finite element model, the material is assigned, and the mode is analyzed by applying constraints according to the actual conditions. The performance is compared with that without the support tool to analyze the impact of the maximum amplitude on the performance of the welding system.

[0045] S3. Based on performance analysis, a support base matching the support tool was designed, and the bottom and sides of the support base were designed for lightweighting. Specifically, the support base was designed according to the natural frequency of the support tool in Table 1 to ensure that the vibration of the welding system would not cause resonance in the support base. According to the test results, the maximum deformation of the support base is approximately 0.9 μm, the average amplitude of the contact surface with the support tool does not exceed 0.4 μm, and the maximum stress is approximately 8 MPa. The material of the support base is 45# steel, with a yield strength of approximately 355 MPa. Therefore, the base will not experience resonance failure. In summary, the base has high rigidity during welding vibration, and the welding quality will not be reduced due to deformation of the base during welding.

[0046] Table 1 Natural Frequency of Support Base

[0047]

[0048]

[0049] The present invention also provides an ultrasonic welding fixing structure based on the vibration extreme point. The structure is implemented by the above method and specifically includes support tools 2 symmetrically arranged on the left and right sides of the welding head 1. The end of the support tool 2 away from the welding head 1 is fixed to the support base 4 by a pressure plate 3. Further, the support tool 2 includes a first connecting end 5 and a second connecting end 6 that are perpendicular to each other. The first connecting end 5 is integrally designed with the welding head 1. The front and rear sides of the second connecting end 6 are respectively connected to the pressure plate 3 and the support base 4. The pressure plate 3 and the support base 4 are detachably connected by bolts 7.

[0050] In summary, the ultrasonic welding fixing method and structure based on vibration extreme points provided by this invention, combined with actual welding requirements, selects a suitable position on the side of the welding head to add support tools, and through comprehensive analysis and judgment, optimizes the performance of the welding system to the greatest extent. In addition, the overall performance of the welding system can be further improved through the improved design of the support base.

[0051] The above description is only 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. An ultrasonic welding and fixing method based on vibration extreme points, characterized in that, The ultrasonic welding fixing method includes the following steps: S1. Perform deformation amplitude analysis on the surface of the welding head and select the surface far away from the welding surface as the supporting connection surface; S2. The support tool and the welding head are integrally formed. By analyzing the system vibration performance of the welding head with the added support tool, a support structure with a small amplitude is designed on the corresponding side of the welding head. S3. Design a support base that matches the support tool based on performance analysis, and carry out lightweight design on the bottom and sides of the support base; The method for analyzing the system vibration performance in step S2 is as follows: after optimizing the Hypermesh mesh, perform finite element analysis, divide the appropriate mesh according to the model shape, or divide the elements according to the force and stress concentration, and after obtaining the element model, import it into ANSYS to establish a finite element model, assign materials, apply constraints according to actual conditions to analyze the modes, and compare the performance with that without support tools to analyze the impact of the maximum amplitude on the performance of the welding system. An ultrasonic welding fixing structure based on the vibration extreme point is formed by adopting the above ultrasonic welding fixing method. The ultrasonic welding fixing structure includes support tools (2) symmetrically arranged on the left and right sides of the welding head (1). The end of the support tool (2) away from the welding head (1) is fixed to the support base (4) by a pressure plate (3). The support tool (2) includes a first connecting end (5) and a second connecting end (6) that are perpendicular to each other. The first connecting end (5) is designed integrally with the welding head (1). The front and rear sides of the second connecting end (6) are respectively connected to the pressure plate (3) and the support base (4).

2. The ultrasonic welding and fixing method based on vibration extreme points according to claim 1, characterized in that: In step S1, the side of the welding head is selected as the supporting connection surface, and the first position K1 and the second position K2 are selected according to the overall deformation amplitude and longitudinal deformation amplitude of the side of the welding head.

3. The ultrasonic welding and fixing method based on vibration extreme points according to claim 2, characterized in that: Support tools were added at the first position K1 and the second position K2 respectively to perform amplitude analysis.

4. The ultrasonic welding and fixing method based on vibration extreme points according to claim 1, characterized in that: In step S3, the support base is designed according to the natural frequency of the support tool to ensure that the vibration of the welding system will not cause resonance of the support base.

5. The ultrasonic welding and fixing method based on vibration extreme points according to claim 1, characterized in that: In step S3, the material for the support base is 45 steel.

6. The ultrasonic welding and fixing method based on vibration extreme points according to claim 1, characterized in that: The pressure plate (3) and the support base (4) are detachably connected by bolts (7).

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