Ultrasonic welding head and ultrasonic welding device

Abstract

An ultrasonic welding head comprises a welding head body, the welding head body is configured to be an integrally-formed piece and comprises an acoustic rod, a swing rod and a connecting piece, the acoustic rod is connected with an ultrasonic vibration source or connected with the ultrasonic vibration source through an amplitude-change pole, and the swing rod is perpendicularly arranged relative to the acoustic rod. The swing rod comprises a first swing rod connected with a connecting piece and a second swing rod with a mounting position at the tail end. The welding head terminal is detachably and rigidly installed at the installation position and resonates with the welding head body. The swing rod and the welding head terminal have a bending mode, and the second swing rod and the welding head terminal each comprise at least one acoustic node. The welding head terminal of the ultrasonic welding head can be replaced to prevent the whole ultrasonic welding head from being scrapped after being abraded, so that the use cost of an ultrasonic welding process is reduced. The utility model further provides an ultrasonic welding device.

Description

Technical Field

[0001] The utility model belongs to the field of ultrasonic welding, and in particular relates to an ultrasonic welding head and an ultrasonic welding device. Background Art

[0002] Ultrasonic welding technology has the advantages of low energy consumption, high speed, high precision, high bonding strength, and no sparks. It has been widely used in electronic manufacturing, lithium batteries, automobiles, textiles and other industries. In order to ensure energy conduction efficiency and improve welding quality, the ultrasonic welding head components need to be precisely processed to form various acoustic structures. Figure 1 The wedge-rod type ultrasonic horn shown includes an acoustic rod 31, an upper swing rod 32 and a lower swing rod 33, wherein the end of the lower swing rod 33 is the working surface of the ultrasonic horn, and a mass block 34 is provided at the upper end of the upper swing rod 33 to provide pressure in the direction of arrow a. Once the end of the lower swing rod 33 is worn, the acoustic properties of the ultrasonic horn will change, resulting in a decrease in the welding effect. Such an ultrasonic horn has a high scrapping cost, resulting in a waste of resources. Therefore, providing an ultrasonic horn to reduce the use cost of the ultrasonic horn has a high practical value. Utility Model Content

[0003] The utility model aims to provide an ultrasonic welding head to reduce the replacement cost of the ultrasonic welding head after it is worn. The utility model also provides an ultrasonic welding device.

[0004] According to an embodiment of one aspect of the utility model, an ultrasonic welding head is provided, including a welding head body, the welding head body is configured as an integrally formed part, including an acoustic rod, a swing rod and a connecting piece, wherein the acoustic rod is connected to an ultrasonic vibration source, and the swing rod is vertically arranged relative to the acoustic rod. Wherein, the swing rod includes a first swing rod and a second swing rod, the first swing rod and the second swing rod are coaxially arranged on both sides of the acoustic rod, the end of the first swing rod is connected to the connecting piece, and the end of the second swing rod is provided with a mounting position; the ultrasonic welding head also includes a welding head terminal, the welding head terminal is detachably and rigidly mounted on the mounting position, the natural frequency of the welding head terminal is coupled with the natural frequency of the welding head body and resonates under the action of the ultrasonic vibration source (including an ultrasonic generator and a transducer); the swing rod and the welding head terminal have a bending mode, and the second swing rod and the welding head terminal both contain at least one acoustic node.

[0005] The resonance between the welding head terminal and the welding head body can effectively transmit ultrasonic vibration. After the welding head terminal is worn, only the welding head terminal needs to be replaced, which effectively reduces the use cost of the ultrasonic welding head.

[0006] Furthermore, in some embodiments, the length of the acoustic rod is an integer multiple of half a wavelength and includes at least one acoustic node. The acoustic rod transmits the vibration of the ultrasonic vibration source to the pendulum along the length direction. When the length of the acoustic rod is an integer multiple of half a wavelength and includes an acoustic node, the pendulum is located at the antinode of the acoustic rod vibration, which can fully excite the vibration of the pendulum.

[0007] Furthermore, in some embodiments, the connection position between the first swing rod and the connecting member is an acoustic node. The acoustic node position has the smallest amplitude, so the connection position between the first swing rod and the connecting member basically does not vibrate, avoiding loss when the connecting member is clamped.

[0008] Furthermore, in some embodiments, the mounting position is arranged at the antinode position in the bending mode of the second swing rod. The mounting position is arranged at the antinode position, which can effectively improve the transmission efficiency of the ultrasonic vibration and increase the effective amplitude of the welding head terminal.

[0009] Furthermore, in some embodiments, the end of the welding head terminal is the antinode position of the bending mode. The end of the welding head terminal has the largest amplitude and can effectively transfer energy to the workpiece to be welded.

[0010] Furthermore, in some embodiments, the mounting position is provided with a stud, and the welding head terminal and the second swing arm are connected together via the stud.

[0011] Furthermore, in some embodiments, a wrench groove is provided around the welding head terminal.

[0012] Furthermore, in some embodiments, the mounting position is provided with a boss or a recessed hole, the welding head terminal is provided with a matching recessed hole or boss, and the welding head terminal is clamped in the mounting position and fixed by a connecting bolt or a connecting pin.

[0013] Furthermore, in some embodiments, a second acoustic rod is also included, the length of the second acoustic rod is an integer multiple of a half wavelength and includes at least one acoustic node, and the second acoustic rod and the acoustic rod are coaxially arranged and respectively arranged on both sides of the pendulum rod.

[0014] According to another embodiment of the utility model, an ultrasonic welding device is provided, including an ultrasonic vibration source and an ultrasonic horn, wherein the ultrasonic vibration source drives the ultrasonic horn, wherein the ultrasonic horn is configured as the ultrasonic horn provided in any of the aforementioned embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of an ultrasonic welding head in a pair of ratios;

[0016] Figure 2This is a schematic diagram of the structure of an ultrasonic welding head in an embodiment;

[0017] Figure 3 It is a schematic diagram of the structure of an ultrasonic welding head in another embodiment;

[0018] Figure 4 A schematic diagram of the structure of an ultrasonic welding head in another embodiment;

[0019] Figure 5 A schematic diagram of an ultrasonic welding head mode in an embodiment;

[0020] Figure 6 Schematic diagram of the ultrasonic welding head mode in another embodiment.

[0021] The meaning of the accompanying drawings: 11-acoustic rod; 12-first rocker arm; 13-second rocker arm; 14-connecting piece; 15-second acoustic rod; 21-welding head terminal; 22-wrench slot; 23-bolt hole; 31-acoustic rod; 32-upper rocker arm; 33-lower rocker arm; 34-connecting piece; 41-vibration mode; 42-vibration mode; 43-vibration mode; 44-vibration mode; 45-vibration mode; 46-vibration mode.

[0022] The purpose of the above drawings is to provide a detailed description of the present invention so that those skilled in the art can understand the technical concept of the present invention, but it is not intended to limit the present invention. For the sake of simplicity, the above drawings only schematically depict the structural parts related to the technical features of the present invention, and do not strictly depict the complete structure and all details in accordance with the actual proportion. DETAILED DESCRIPTION

[0023] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0024] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The phrase appearing in various locations in the specification does not necessarily refer to the same embodiment, nor is it limited to mutually exclusive independent or alternative embodiments. Those skilled in the art should be able to understand that the embodiments herein may be combined with other embodiments without causing structural conflicts.

[0025] In the description of this article, unless otherwise clearly specified and limited, the technical terms "installed", "connected", "connected" and the like should be understood in a broad sense, which can be a movable connection, a fixed connection or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

[0026] In the description of this document, terms indicating orientation or positional relationships, such as "up", "down", "left", "right", "horizontal", "vertical", "height", "length", and "width", are intended to accurately describe the embodiments and simplify the description, but are not intended to limit the parts or structures involved to have a specific orientation, be installed or operate in a specific orientation, and should not be construed as a limitation on the embodiments in this document.

[0027] In the description of this article, the terms "first", "second" and the like are only used to distinguish different objects, and cannot be understood as indicating relative importance or limiting the quantity, specific order or primary and secondary relationship of the described technical features. In the description of this article, the meaning of "plurality" is at least two.

[0028] like Figure 1 The ultrasonic welding head shown includes an acoustic rod 31 and an upper swing rod 32 and a lower swing rod 33 vertically connected to the acoustic rod 31, and the upper swing rod 32 and the lower swing rod 33 are separated by the acoustic rod 31. Among them, one end of the acoustic rod 31 is connected to an ultrasonic vibration source, and the ultrasonic vibration is transmitted along the length direction of the acoustic rod 31 and excites the resonance of the upper swing rod 32 and the lower swing rod 33. The end of the lower swing rod 33 is a free end for performing welding operations; the end of the upper swing rod 32 is connected to a mass block 34, and the mass block 34 applies downward pressure to the integrated welding head in the direction of arrow a through its own weight or an external force. Since the acoustic performance of the ultrasonic welding head is closely related to its own geometric structure, during long-term use, the lower swing rod 33 that is in direct contact with the workpiece to be welded will inevitably wear out, resulting in the attenuation of the overall acoustic performance of the ultrasonic welding head. The overall structure of the ultrasonic welding head is very precise, and the material and processing costs are high. The scrapping of the ultrasonic welding head will significantly increase the operating cost of ultrasonic welding.

[0029] In order to solve the above problems, the embodiments of the present invention provide a Figure 2The ultrasonic horn shown in the figure comprises a horn body, which comprises an acoustic rod 11, a swing rod including a first swing rod 12 and a second swing rod 13, and a connecting piece 14. The first swing rod 12 and the second swing rod 13 are respectively arranged on both sides of the acoustic rod 11 along the same straight line, and the connecting piece 14 is arranged at the end of the first swing rod 12. The horn body is an integrally formed part and has complete acoustic performance of the ultrasonic horn. The acoustic rod 11 is connected to the ultrasonic vibration source. During the working process, the ultrasonic vibration propagates along the length direction of the acoustic rod 11 and transmits the vibration to the first swing rod 12 and the second swing rod 13. A mounting position is arranged at the end of the second swing rod 13, and a stud (not shown) is arranged on the mounting position. The horn terminal 21 is fixedly connected to the end of the second swing rod 13 through the stud. The natural frequency of the horn terminal 21 is coupled with the natural frequency of the horn body. Under the action of the ultrasonic vibration source, the horn terminal 21 and the horn body can resonate. In a preferred embodiment, the cross-sectional area of ​​the second swing arm 13 is not less than the maximum cross-sectional area of ​​the welding head terminal 21 .

[0030] Combination Figure 5 , the first swing rod 12 and the second swing rod 13 have a vibration mode 42, and the welding head terminal has a vibration mode 43. Both the vibration mode 42 and the vibration mode 43 are bending modes (the amplitude direction is perpendicular to the length direction). The length of the second swing rod 13 is an integer multiple of half the wavelength ( Figure 5 In the embodiment shown, the length of the second swing rod 13 is equal to half the wavelength) and includes at least one acoustic node (amplitude is 0). In this way, the installation position of the end of the second swing rod is set at the antinode position in the bending mode (maximum amplitude), which can effectively transmit the vibration to the welding head terminal 21. The length of the welding head terminal 21 is also set to an integer multiple of half the wavelength ( Figure 5 In the illustrated embodiment, the welding head terminal has a length equal to half a wavelength) and includes at least one acoustic node, so that the end of the welding head terminal 21 (that is, the working area of ​​the ultrasonic welding head) is the position with the largest amplitude, which can effectively output the energy generated by ultrasonic vibration to the workpiece to be welded.

[0031] In a preferred embodiment, the length of the acoustic rod 11 is an integer multiple of a half wavelength ( Figure 5 In the embodiment shown, the acoustic rod 11 has a length equal to half a wavelength and includes at least one acoustic node. Thus, as shown in the vibration mode 41, one end of the acoustic rod 11 is connected to the ultrasonic vibration source, and the amplitude is the largest, while the other end of the acoustic rod 11, the connection position of the first pendulum rod 12 and the second pendulum rod 13 is also at the position of the maximum amplitude, so the first pendulum rod 12 and the second pendulum rod 13 can be effectively excited, thereby improving the energy transfer efficiency.

[0032] In a preferred embodiment, if Figure 5As shown in the middle vibration mode 42, the connection position between the first rocker arm 12 and the connecting member 14 is an acoustic node with a minimum vibration amplitude, so that the connecting member 14 basically does not generate horizontal vibration, so that the connecting member 14 can be connected to other parts that do not vibrate.

[0033] In another embodiment, the structure of the ultrasonic horn is as follows: Figure 3 As shown, it includes an integrated welding head body and a detachable welding head terminal 21. The welding head body includes an acoustic rod 11, a first swing rod 12, a second swing rod 13, a connecting piece 14 connected to the end of the first swing rod 12, and also includes a second acoustic rod 15 with a structure similar to the acoustic rod 11. The second acoustic rod 15 is coaxially arranged with the acoustic rod 11 and is respectively arranged on both sides of the swing rod. In some embodiments, the second acoustic rod 15 is arranged to have the same structure as the acoustic rod 11, and the two are symmetrically arranged; in other embodiments, the structure of the second acoustic rod 15 may be different from that of the acoustic rod 11. Under the action of an ultrasonic vibration source, the welding head body and the welding head terminal 21 can resonate. In the resonant state, as Figure 6 As shown, the length of the acoustic rod 11 and the second acoustic rod 15 is respectively equal to half a wavelength, and each includes an acoustic node. As shown in the vibration mode 44, the first swing rod 12 and the second swing rod 13 are connected at the position with the largest amplitude in the vibration mode 44. The first swing rod 12 and the second swing rod 13 have a bending mode as shown in the vibration mode 45, and generate an amplitude perpendicular to the length direction under the excitation of the acoustic rod 11, while the length of the second swing rod 13 is equal to half a wavelength and includes an acoustic node, so the end of the second swing rod 13 is at the position with the largest amplitude. A stud (not shown) is provided at the end of the second swing rod 13, and a matching screw hole is provided on the welding head terminal 21. The welding head terminal 21 is tightened on the stud to achieve a rigid connection with the second swing rod. A wrench groove 22 is provided on the peripheral surface of the welding head terminal 21 so that a torque can be applied to the welding head terminal 21 by a wrench or other tools during the installation or removal of the welding head terminal 21. The welding head terminal 21 is configured as a multi-segment structure consisting of multiple segments of approximately truncated cones, and the cross-sectional area gradually decreases from the connection with the second swing rod 13 to the free end. By arranging the second acoustic rod 15 on the welding head body, the overall acoustic characteristics of the ultrasonic welding head can be changed to better meet the actual production needs; in some embodiments, the end of the second acoustic rod 15 can also be connected to another synchronous ultrasonic vibration source to increase the power of ultrasonic welding.

[0034] In yet another embodiment, Figure 3As shown, there is no stud between the welding head terminal 21 and the second swing arm 13, a cylindrical boss (not shown) is provided at the end of the second swing arm 13, and a matching circular recess (not shown) is provided on the welding head terminal 21, the welding head terminal 21 is plugged into the cylindrical boss at the end of the second swing arm 13, and a rigid connection is achieved by a fastening bolt (not shown) provided in a bolt hole 23 provided radially along the welding head terminal 21. Figure 3 In the illustrated embodiment, the installation and removal of the welding head terminal 21 can be achieved by a crescent wrench. In other embodiments, the fastening bolt can also be replaced by a connecting pin or other structures with a locking function.

[0035] Another embodiment of the utility model provides an ultrasonic welding device, which adopts the split ultrasonic welding head adopted in any of the above embodiments, and the ultrasonic vibration source is connected to the end of the acoustic rod of the ultrasonic welding head to provide energy input. In different embodiments, the ultrasonic vibration source includes an ultrasonic generator and a transducer, and one or more amplitude modulators can be set between the transducer and the acoustic rod to output ultrasonic vibrations with different waveforms or amplitudes. When the ultrasonic welding head adopts Figure 3 or Figure 4 When the structure with the second acoustic rod 15 is shown, in different embodiments, the ultrasonic welding device may be connected to an ultrasonic vibration source only at the end of the acoustic rod 11, or may be connected to synchronously vibrating ultrasonic vibration sources at the ends of the acoustic rod 11 and the second acoustic rod 15. In some embodiments, the ultrasonic welding device applies vertical pressure to the welding head terminal 21 through the gravity of the connecting member 14 so that the welding head terminal is pressed against the workpiece to be welded; in other embodiments, the ultrasonic welding device is further provided with a pressure device on the connecting member 14, and applies additional pressure to the swing rod and the welding head terminal 21 through the connecting member 14 so that the welding head terminal is pressed against the surface of the workpiece to be welded.

[0036] The purpose of the above embodiments is to further explain the present invention in detail in conjunction with the accompanying drawings so that those skilled in the art can understand the technical concept of the present invention. Within the scope of the present invention, the optimization or equivalent replacement of the structure of the parts involved, and the combination of the implementation methods in different embodiments without conflict of structure and principle, all fall within the protection scope of the present invention.

Claims

1. An ultrasonic welding head, comprising a welding head body, wherein the welding head body is configured as an integrally formed part, comprising an acoustic rod, a swing rod and a connecting piece, wherein the acoustic rod is connected to an ultrasonic vibration source or connected to the ultrasonic vibration source through an amplitude modulator, and the swing rod is vertically arranged relative to the acoustic rod, characterized in that: The swing rod comprises a first swing rod and a second swing rod, the first swing rod and the second swing rod are coaxially arranged on both sides of the acoustic rod, the end of the first swing rod is connected to the connecting member, and the end of the second swing rod is provided with a mounting position; The ultrasonic horn further comprises a horn terminal, which is detachably and rigidly mounted on the mounting position, and the natural frequency of the horn terminal is coupled with the natural frequency of the horn body and resonates under the action of the ultrasonic vibration source; The swing rod and the welding head terminal have a bending mode, and the second swing rod and the welding head terminal each include at least one acoustic node.

2. The ultrasonic horn according to claim 1, characterized in that: The acoustic rod has a length that is an integral multiple of a half wavelength and includes at least one acoustic node.

3. The ultrasonic horn according to claim 1, characterized in that: The connection position between the first swing rod and the connecting member is an acoustic node.

4. The ultrasonic horn according to claim 1, characterized in that: The mounting position is arranged at an antinode position in the bending mode of the second swing rod.

5. The ultrasonic horn according to claim 1, characterized in that: The end of the welding head terminal is the antinode position of the bending mode.

6. The ultrasonic horn according to claim 1, characterized in that: The installation position is provided with a stud, and the welding head terminal and the second swing arm are connected together through the stud.

7. The ultrasonic horn according to claim 6, characterized in that: A wrench groove is arranged around the welding head terminal.

8. The ultrasonic horn according to claim 1, characterized in that: The installation position is provided with a boss or a recessed hole, and the welding head terminal is provided with a matching recessed hole or boss to allow the welding head terminal to be clamped in the installation position and fixed by a connecting bolt or a connecting pin.

9. The ultrasonic horn according to any one of claims 1 to 8, characterized in that: It also includes a second acoustic rod, the length of which is an integral multiple of a half wavelength and includes at least one acoustic node, and the second acoustic rod is coaxially arranged with the acoustic rod and is respectively arranged on both sides of the pendulum rod.

10. An ultrasonic welding device, comprising an ultrasonic vibration source and an ultrasonic welding head, characterized in that: The ultrasonic horn is configured as the ultrasonic horn as claimed in any one of claims 1 to 9.

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