Laser hybrid ultrasonic welded joint and method of use thereof

Abstract

This invention discloses a laser-hybrid ultrasonic welding joint. The joint has a through-hole in the center allowing laser light to pass through. The through-hole is filled with water, and its inner wall is a polished reflective wall. The laser beam can undergo total internal reflection between the water and the polished reflective wall interface within the through-hole. This invention also discloses a laser surface pretreatment and selective curing bonding method for safety tools using the aforementioned laser-hybrid ultrasonic welding joint. First, the laser is guided to penetrate a transparent component and radiate to the interface to be welded, pre-forming a ring-shaped melting zone. Then, the laser-hybrid ultrasonic welding joint is used to cure and bond the transparent component to the safety tool. This invention further discloses a laser-hybrid ultrasonic welding method for electronic tags in safety tools using the aforementioned laser-hybrid ultrasonic welding joint.

Description

Technical Field

[0001] This invention relates to special equipment for power safety, and more particularly to a laser composite ultrasonic welding joint and its application method. Background Technology

[0002] With the continuous development and improvement of national power safety equipment, safety tools and equipment used to prevent accidents such as electric shock, burns, falls, and tumbles are increasingly frequently applied. These include insulated safety tools and equipment such as voltage detectors, insulating rods, insulating covers, insulating gloves, and insulating boots, which prevent injury to operators from contact voltage, step voltage, leakage current, and electric arcs. To prevent accidental injuries, the intelligent management of safety tools and equipment is receiving increasing attention. Currently, intelligent management of safety tools and equipment is achieved by installing electronic tags in the form of plastic-coated chips. The common method for welding electronic tags to safety tools and equipment is ultrasonic welding. In ultrasonic welding, a weld guide line needs to be designed. This weld guide line can increase the quality and strength of the weld, shorten the welding time, improve welding efficiency, and reduce phenomena such as incomplete welds and excess adhesive. However, for electronic tag welding, it is impossible to directly design the weld guide line on its surface, which often leads to problems such as unreliable welds during the welding process. Therefore, there is an urgent need for a welding device and process suitable for electronic tags used in safety tools and equipment to solve the technical problem of not being able to design a weld guide line during ultrasonic welding of electronic tags. The invention disclosed in CN107225327A discloses an ultrasonic-assisted laser brazing method for dissimilar metal assemblies, comprising: (1) clamping a metal column A using a positioning mold; (2) heating the upper end of the metal column A to a softened state; (3) inserting the softened upper end of the metal column A into the contour hole of a metal base B to obtain a dissimilar metal laser-welded pre-assembly; (4) activating an ultrasonic vibration source connected to the positioning mold assembly; turning on the laser, and under the assistance of the ultrasonic vibration composite energy field, performing fusion brazing along the contour line of the connection surface between the metal column A and the metal base B; (5) moving the dissimilar metal laser-welded assembly onto a conveyor belt, and then dropping it into a material box. This invention can achieve a welding effect with large penetration depth and narrow weld seam, resulting in a welded joint with better metallurgical quality. This invention also provides an ultrasonic-assisted laser brazing device for dissimilar metal assemblies. However, the equipment used in this invention is relatively complex and requires the use of brazing filler metal, resulting in higher process costs. Summary of the Invention

[0003] When performing ultrasonic welding on electronic tags, it is impossible to directly design welding guide lines on their surface, which often leads to problems such as unreliable welding during the welding process. To overcome these defects, this invention provides a laser composite ultrasonic welding joint and its application method that can solve the problem of not being able to design welding guide lines on electronic tags and improve the welding strength between safety tools and electronic tags.

[0004] The technical solution of this invention is as follows: A laser-hybrid ultrasonic welding joint, wherein the ultrasonic welding joint has a through hole in the middle to allow laser light to pass through. The through hole is filled with water, and the inner wall of the through hole is a polished reflective wall. The laser beam can undergo total internal reflection between the water and the polished reflective wall interface within the through hole. This specific structure of the laser-hybrid ultrasonic welding joint allows the laser to be emitted from the water-filled through hole and irradiate the welding interface. Pre-treatment is performed using the advantages of laser welding—non-contact, long-distance, and less constrained by space—before ultrasonic welding. The water filling in the through hole cools the reflective wall. This laser-hybrid ultrasonic welding joint can be used for welding components where it is difficult to set a weld line.

[0005] A laser surface pretreatment and selective curing bonding method for safety tools using the aforementioned laser-hybrid ultrasonic welding joint involves first guiding the laser through a transparent component to radiate onto the interface to be welded, pre-forming a melt-conducting zone, and then using the laser-hybrid ultrasonic welding joint to cure and bond the transparent component to the safety tool. Electronic tags are typically transparent components, making this method suitable for installation on safety tools.

[0006] A method for laser-based ultrasonic welding of electronic tags for safety tools using the aforementioned laser-based ultrasonic welded joint includes the following steps:

[0007] Step 1. Clean and dry the safety tools and the surfaces of the electronic tags to be welded;

[0008] Step 2. Clamp the electronic tag and safety tool together using a clamp to ensure that the electronic tag and the interface to be welded on the safety tool are in contact.

[0009] Step 3. Press the laser composite ultrasonic welding joint onto the electronic tag, introduce the welding laser, and adjust the position of the laser focus in the water so that the laser incident angle meets the total internal reflection condition, so that the laser undergoes continuous total internal reflection at the interface between the water and the reflective wall, and finally use the water to guide the laser through the transparent electronic tag to irradiate the surface of the safety tool.

[0010] Step 4. Adjust the continuous wave laser process parameters. The laser irradiates the surface of the safety tool to form a molten pool. The heat emitted by the molten pool melts the electronic tag, forming a melt-conducting zone.

[0011] Step 5. Adjust the ultrasonic welding parameters to obtain a good welding interface, so that the electronic tag is firmly welded to the surface of the safety tool.

[0012] This safety tool uses a laser-assisted ultrasonic welding method for electronic tags, which primarily uses ultrasound and secondarily uses laser. After forming a pre-conducting melting zone with laser, ultrasonic welding is performed. This method is used to solve the problem that conventional plastic-shell-coated chip electronic tags are difficult to pre-design the melting lines at an acceptable production cost.

[0013] Preferably, the cleaning and drying process in step one is limited to ensuring that there are no visible impurities at the interface to be welded. The interface to be welded must be thoroughly cleaned and dried to ensure full reception of laser energy.

[0014] Preferably, in step two, the contact between the electronic tag and the interface to be welded on the safety tool should be limited to prevent significant misalignment of the interface. This ensures that the electronic tag can be installed correctly.

[0015] Preferably, in step three, the laser is tilted and the laser beam rotates around the axis of the ultrasonic welding joint, ultimately forming a ring-shaped irradiation area on the interface to be welded. The laser beam rotates around the axis of the ultrasonic welding joint, and after reflection, it finally falls on the interface to be welded, melting out a ring-shaped area. This ensures that the electronic tag has weld points in all directions while avoiding an excessively large melting area, thus reducing energy consumption.

[0016] Preferably, in step three, the laser focus is positioned in the water so that the laser incident angle satisfies the total internal reflection condition at the interface between the water and the reflective wall, allowing the laser beam to undergo continuous total internal reflection.

[0017] As a preferred option, the laser process parameters in step four are: laser power of 200W to 300W; defocusing amount of -20mm to 20mm; and the continuous laser spot used is a circular spot.

[0018] As a preferred option, the ultrasonic welding process parameters in step five are: ultrasonic pressure of 0.36MPa to 0.52MPa, ultrasonic time of 0.2s to 0.42s, and pressure holding time of 0.2s to 0.42s.

[0019] The beneficial effects of this invention are:

[0020] Integrating laser welding into ultrasonic welding greatly improves the strength of the weld.

[0021] By using lasers to pre-form a melt-guiding zone at the welding interface between the electronic tag and the safety tool, the problem of not being able to design melt-guiding lines for electronic tags is solved.

[0022] By adjusting the laser and ultrasonic welding parameters, electronic tags can be welded and installed on different types of safety tools. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of one structure of the present invention.

[0024] In the figure, 1-ultrasonic welding joint, 2-laser head, 3-through hole, 4-polished reflective wall, 5-rotating cylinder, 6-electronic tag, 7-safety tool, 8-molten pool. Detailed Implementation

[0025] The present invention will be further described below through specific embodiments and in conjunction with the accompanying drawings.

[0026] Example 1:

[0027] like Figure 1 As shown, a laser-hybrid ultrasonic welding joint includes an ultrasonic welding joint 1 and a laser head 2. The laser head 2 contains a laser source and a focusing lens. The ultrasonic welding joint 1 has a through hole 3 in the middle, which allows the laser to pass through. The through hole 3 is filled with water, and the inner wall of the through hole 3 is a polished reflective wall 4. The laser beam can undergo total internal reflection between the water and the polished reflective wall 4 in the through hole 3. A rotating cylinder 5 is rotatably connected to the top of the ultrasonic welding joint 1. The rotating cylinder 5 is coaxial with the ultrasonic welding joint 1. The laser head 2 is fixed inside the rotating cylinder 5. An external toothed ring is provided on the outer wall of the rotating cylinder 5, so that the rotating cylinder 5 is connected to an external power source through a gear transmission mechanism.

[0028] A laser surface pretreatment and selective curing bonding method for safety tools using the laser-composite ultrasonic welding joint involves first guiding the laser to penetrate the transparent component and radiate to the interface to be welded to pre-form a melting zone, and then using the laser-composite ultrasonic welding joint to cure and bond the transparent component to the safety tool.

[0029] A method for laser-based ultrasonic welding of electronic tags for safety tools using the aforementioned laser-based ultrasonic welded joint includes the following steps:

[0030] Step 1. Clean and dry the surfaces of the safety tools and electronic tags to be welded, ensuring that there are no visible impurities at the welding interface.

[0031] Step 2. Clamp the electronic tag 6 and the safety tool 7 together using a clamp to ensure that the interface to be welded is in contact with the electronic tag 6 and the interface to be welded on the safety tool 7. The degree of contact between the electronic tag 6 and the interface to be welded on the safety tool 7 should be limited to the extent that the interface to be welded does not shift arbitrarily.

[0032] Step 3. Press the ultrasonic welding joint 1 onto the electronic tag 6, start the laser head 2, introduce the welding laser, adjust the position of the laser focus in the water so that the laser incident angle meets the total reflection condition, so that the laser undergoes continuous total reflection at the interface between the water and the reflective wall, and finally use the water to guide the laser through the transparent electronic tag 6 to irradiate the surface of the safety tool 7. The laser focus is in the water so that the laser incident angle meets the total reflection condition at the interface between the water and the reflective wall, and the laser beam undergoes continuous total reflection.

[0033] Step 4. Adjust the continuous wave laser process parameters. The laser irradiates the surface of the safety tool 7 to form a molten pool 8. The heat emitted by the molten pool 8 melts the electronic tag 6, forming a melt-conducting zone. The laser process parameters are: laser power of 250W; laser focal length of 517mm; defocusing amount of -10mm; the continuous laser spot used is a circular spot with a spot diameter of 175μm.

[0034] Step 5. Adjust the ultrasonic welding parameters to obtain a good welding interface, so that the electronic tag 6 is firmly welded to the surface of the safety tool 7. The ultrasonic welding process parameters are: ultrasonic pressure 0.49MPa, ultrasonic time 0.29s, pressure holding time 0.29s, and working frequency 20kHz.

[0035] Example 2:

[0036] The laser process parameters in step four are: laser power of 200W; defocusing distance of -20mm. The ultrasonic welding process parameters in step five are: ultrasonic pressure of 0.36MPa, ultrasonic time of 0.42s, and holding time of 0.42s. The rest are the same as in Example 1.

[0037] Example 3:

[0038] The laser process parameters in step four are: laser power of 300W and defocusing distance of 20mm. The ultrasonic welding process parameters in step five are: ultrasonic pressure of 0.52MPa, ultrasonic time of 0.2s, and pressure holding time of 0.2s.

Claims

1. A method for laser-composite ultrasonic welding of electronic tags for safety tools using laser-composite ultrasonic welding joints, wherein the ultrasonic welding joint has a through hole in the middle allowing laser to pass through, the through hole is filled with water, and the inner wall of the through hole is a polished reflective wall, and the laser beam can undergo total internal reflection between the interface between the water and the polished reflective wall in the through hole, characterized in that... It comprises the following steps: Step one. The safety tool and electronic tag to be welded surface cleaning, drying treatment; Step two. The electronic tag and safety tool with clamps clamped, so that the electronic tag and safety tool to be welded interface fit; Step three. The laser composite ultrasonic welding joint is pressed on the electronic tag, the welding laser is introduced, the position of the laser focus in the water is adjusted, the laser incidence angle meets the total reflection condition, so that the laser occurs continuous total reflection in the water and the reflection wall interface, and finally the water guides the laser to penetrate the transparent electronic tag and irradiate to the safety tool surface, the laser is inclined to irradiate, and the laser beam rotates around the axis of the ultrasonic welding joint, and finally an annular irradiation range is formed on the to-be-welded interface; Step four. Adjust the continuous wave laser process parameters, and the laser irradiates on the safety tool surface to form a molten pool, the heat emitted by the molten pool melts the electronic tag, and an annular molten zone matching the shape of the electronic tag is formed; Step five. Adjust the ultrasonic welding parameters to obtain a good welding interface, so that the electronic tag is firmly welded on the safety tool surface.

2. The electronic tag laser composite ultrasonic welding method for safety tool according to claim 1, characterized in that The cleaning and drying treatment in step one is limited to the case where there is no visible impurities on the to-be-welded interface.

3. The electronic tag laser composite ultrasonic welding method for safety tool according to claim 1, characterized in that The fit of the electronic tag and safety tool to be welded interface in step two is limited to the case where the to-be-welded interface does not deviate greatly.

4. The electronic tag laser compound ultrasonic welding method for safety tool according to claim 1, characterized by, The laser composite ultrasonic welding joint comprises an ultrasonic welding joint and a laser head ultrasonic welding joint, and a rotating cylinder is rotatably connected to the top end of the ultrasonic welding joint, the rotating cylinder is coaxial with the ultrasonic welding joint, the laser head is fixed in the rotating cylinder, and an outer gear ring is arranged on the outer wall of the rotating cylinder, so that the rotating cylinder is in transmission connection with the external power source through a gear transmission mechanism.

5. The electronic tag laser composite ultrasonic welding method for safety tool according to claim 1, characterized in that In step three, the position of the laser focus in the water is limited to the case where the laser incidence angle meets the total reflection condition of the laser in the water and the reflection wall interface, so that the laser beam occurs continuous total reflection.

6. The electronic tag laser composite ultrasonic welding method for safety tool according to claim 1, characterized in that In step four, the laser process parameters are: the laser power is 200W-300W; the defocusing amount is-20mm-20mm; and the continuous laser spot used is a circular spot.

7. The electronic tag laser compound ultrasonic welding method for safety tool according to any one of claims 1 to 6, characterized by In step five, the ultrasonic welding process parameters are: the ultrasonic pressure is 0.36MPa-0.52MPa, the ultrasonic time is 0.2s-0.42s, and the pressure maintaining time is 0.2s-0.42s.

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