2. 1 35 kHz Ultrasonic plastic welding equipment structure research requirements
For 35 kHz ultrasonic plastic welding mechanical structure, in order to ensure that its structure reasonable development, the following 5 requirements should be met.
(1) we should ensure that the energy in the ultrasonic can be guided to the welding position, usually can be welded line structure made into a sharp corner, and the tip of the corner is set into a chamfering, chamfering radius should be controlled within 0.1mm, In order to form the energy guide, the sharp Angle can choose 45, 60, 90 and 120 degrees, and the energy guide height needs to be adjusted according to the welding part wall thickness and material, generally speaking, the energy guide height should not be less than 1/2 of the material wall thickness, and in order to avoid the problem of excess energy guide. It shall ensure that the radius of chamfering in other mechanical structures shall be above 0.2mm;
(2) In the mechanical structure welding should ensure that the welding horn can fully contact, welding head should be as close as possible to the welding position, so that the welding head can be fully covered by the welding position;
(3) Welding structure should have support mechanical structure, in order to avoid the loss of force in transfer, we can use tooling to support the mechanical structure protection, support surface should be at least twice as much as the welding line joint, and make the support surface as close to the support surface;
(4) in the welding should avoid welding overflow, for amorphous plastic, can not be sealed, the wall thickness of the welding position should be controlled at 1 mm, when the sealing area is not complete, just open its inner side seal, and one of the surfaces can be sealed, so as to effectively protect the appearance of the material quality, And in the welding adhesion is also more guaranteed;
(5) Weld displacement and volume shall be reserved to allow free flow of the melt within the weld position to avoid blocking of the plastic weldment gap.
2. 2 Common ultrasonic line structure
Common ultrasonic line structure mainly are tongue joint, V groove, step joint and shear joint. For the mechanical welding plastic parts with a wall thickness of more than 1.5mm, the tongue and groove welding line structure is the most suitable, and for the mechanical welding products with a wall thickness of about 1mm, the stage welding line structure can be used. When the wall thickness is less than 1 mm, the inclined section type welding line structure can be used, and if the welding product is small, the accuracy and welding quality is high, the V-groove type welding line structure can be used.
3. conclusion
To sum up, when using 35 kHz ultrasonic plastic welding technology to search mechanical structure, it is necessary to consider the sealing property of welding line structure. Step welding line structure can ensure thin wall thickness of parts. At the same time, the development of this structure can also reduce the complexity of mold injection molding process. Then solve the overflow problem effectively, so that the process instability in the welding process is greatly reduced, so that the production efficiency is greatly improved.
Post time: Mar-15-2022