Welding horn design is also an important part of the entire ultrasonic machine design. Using improperly processed or uncoordinated welding horn will bring expensive losses to production — destroying the welding effect, and more seriously, directly causing damage to the transducer and generator.
Therefore, the design of the ultrasonic mold is by no means as simple as its appearance. Instead, it requires a lot of expertise and skills. So, how do you make sure that the welding horn works most economically? How to ensure that the sonotrode can effectively transmit the mechanical vibration converted by the transducer to the workpiece to form a continuous and stable weld?
1. Mold Amplitude Parameters
Since each company chooses different transducers, the amplitude of the transducer output is also different.
By adapting to booster and welding horns with different transformation ratios, the working amplitude of the welding horn can be corrected.
Since each company chooses different transducers, the amplitude of the transducer output is also different.
By adapting amplifiers and welding heads with different transformation ratios, the working amplitude of the welding head can be corrected.
Usually, the output amplitude of the transducer is 10–20μm, and the working amplitude is generally about 30μm. The transformation ratio of the booster and welding horn is related to their shape, the front and rear area ratio, and other factors.
2. Mold Frequency Parameters
All ultrasonic welding machines have a center frequency, such as 20KHz, 40KHz, etc. The working frequency of the welding machine is mainly determined by the transducer, horn and mechanical resonance frequency of the welding machine.
All ultrasonic welding machines have a center frequency, such as 20KHz, 40KHz, etc. The working frequency of the welding machine is mainly determined by the transducer, horn and mechanical resonance frequency of the welding machine.
The frequency of the generator is adjusted according to the mechanical resonance frequency to achieve consistency, so that the welding horn is in a resonance state, and each part is designed as a half-wavelength resonant body. The generator and mechanical resonance frequencies have a resonance operating range, which is generally set to ±0.5KHz. Within this range, the welding machine can almost work normally. When we make each welding head, we will adjust the resonant frequency, requiring the error between the resonant frequency and the design frequency to be less than 0.1KHZ. For example, the frequency of the 20KHz welding head is controlled at 19.90–20.10KHz, with an error of 5‰.
