The ultrasonic plastic welding machine is composed of pneumatic transmission system, control system, ultrasonic generator, sensor, knife head and mechanical device.
1. The pneumatic transmission system includes:
Overflow valve, relief valve, oil mist, commutator, throttle valve, cylinder, etc. Firstly, the vibration system of the ultrasonic sensor which moves up and down the stroke cylinder driven by the air compressor. In the middle and low power ultrasonic welding, the dynamic pressure is adjusted according to the welding requirements.
2. Control system
The control system consists of time relay or integrated circuit timer. Its main functions are as follows: First, control the work of the pneumatic transmission system, open the air valve under the timing control during welding, reduce the cylinder pressure, press the welding object under a certain pressure, hold the pressure for a period of time after welding, and then control the temperature of the system. O Change the direction of the air valve, make the welding joint rise and reset; second, control the working time of the ultrasonic generator, and start the button production only when it is operated. If trigger pulse is generated, the whole welding process can be completed automatically. The sequence of the whole control system is: power start trigger control signal pneumatic transmission system, cylinder pressure welding head drops, welding trigger ultrasonic generator works, start ultrasonic wave and maintain a certain welding time, eliminate ultrasonic emission and maintain a certain pressure time. Decompression, the welding joint rises to the end of the welding.
3. The ultrasonic generator
(1) In the high-power ultrasonic plastic welding machine, the generator signal adopts the phase-locked frequency automatic tracking circuit, so that the output frequency of the generator is basically consistent with the resonance frequency of the sensor.
(2) The generator used in ultrasonic plastic welding machine with power greater than 500W adopts self-excited power oscillator and has certain frequency tracking ability.
4. Acoustic System of Ultrasound Plastic Welding Machine
The acoustic system of the ultrasonic plastic welding machine consists of three parts: one driving part, two fixing parts and three working parts. Among the three components mentioned above, the drive is the core, and the bolt clamped longitudinal vibration sensor is commonly used. A half-wavelength longitudinal oscillator is connected with a quarter-wavelength longitudinal oscillator, a half-wavelength longitudinal oscillator is connected with a half-wavelength acquisition instrument to form a full-wavelength plastic welding sensor, and a quarter-wavelength longitudinal oscillator is connected with a quarter-wavelength acquisition instrument to form a half-wavelength welding sensor. Velength plastic welding sensor. Wavelength sensor.
(2) Knife head
Different welding objects need different tool heads, no matter near-field welding or transmission welding, only half-wavelength tool heads can make the amplitude of the welding end reach saturation value. Knife head, with and without amplitude amplification. The cutter head of the acoustic system of plastic welding machine is usually made of aluminium alloy. The end face is coated with cemented carbide. When the power is high, it is also made of titanium alloy. The fatigue strength of this material is more than twice that of aluminium alloy.