Working Principle
Vibration welding is based on the principle of friction welding. Pressed two pieces of plastic welding together, vibration the one relative to one another to do reciprocating displacement, the maximum displacement of up to 1.8mm or 4mm, the peak value and distance between the amplitude and vibration frequency of 240Hz. It’s like two hands put together friction,so as to produce friction heat.
In this plastic vibration welding process, a part of the welding fixture is in the lift, and another by the assembly position on the driving of the fixture. The lifting platform is perpendicular to the vibration head movement by the hydraulic system.The system provides power and pressure control. The two parts must be pressed by the clamping force of the lifting platform together in friction welding and keep the cycle, the clamping force of the continuing role on plastics. Under compression, the vibration head vibrates,after a few seconds, the plastic melting. This time is called the “welding time”. Then melting in a short time under the pressure of plastic is cooled and solidified, this time called “keep time”. “Keep time”after the end of the lifting platform decreased and returned to the unloading position (initial position).
Important parts
Vibration friction welding machine is composed of 9 main parts:
1) The electric control device 2) vibration source 3) frame 4)vibration head 5)hydraulic system/servo system 6) vibration transmission system7) Sound cover 8) base 9) pneumatic system
The electrical control device and the vibration source is installed on the right side of the vibration welders cabinet. Vibration head, hydraulic station and a mechanical drive installed in the framework. Sound insulation cover on the machine, to prevent vibration generated during noise and protect the operator. The front has a soundproof cover along the vertical direction of sliding door. On the back of the enclosures two pair of double doors, allowing maintenance personnel to enter the vibration welding machine for maintenance.
Electrical control device
The electric control device comprises a programmable controller (PLC), relay, transformer and touch screen are used.The user on the touch screen to operate the machine. PLC control of the source of vibration start and stop motion sequence of hydraulic system and all vibration welding machines and equipment functions.
Vibration power supply
The vibration power mainly provides current driving coil of the vibrating head, the vibration head to vibrate, so called vibration dynamic power supply.
After the replacement of the fixture in the initial start-up and operation time, operator must through the touch screen to adjust the vibration power.The source of the output frequency and output voltage. The output frequency for the resonant frequency tuning of the vibrating head, and output voltage.The corresponding amplitude with the tuning of the vibrating head.
There is a closed loop between the induction coil in power and vibration head and magnet for vibration amplitude feedback.The main performance parameters of the electrical part:
Input voltage: 415VAC
control voltage: 24VDC Power consumption: 30KW
machine frame
The vibration welding system frame is welded steel structure and various specifications. In addition to the cabinet, all the rest
of the machinery, hydraulic,pneumatic parts are mounted on the frame.
Vertical stretching vibration head level vibration load and hydraulic system by pressing the workpiece lifting platform complex loading, request frame must have sufficient strength and rigidity.The linear vibration welding machine frame by four with a rubber pad foot, fell on the ground. The foot is adjustable, when the vibration welders are installed when need to adjust the frame height and level, in order to make the work platform on the table to reach the required level degree (≤0.05mm/1000mm).
Vibrating head
The vibration head will be transformed into two-way linear motion vibration AC power. High strength rubber which is installed on the machine frame rubber pad, rubber pad is used for separating the frame vibration and static vibration of the head.
The vibration head is composed of a large cast iron frame, a spring, a set of drive assembly and the two drive coil. Spring is fascicular cantilever, they used the whole high strength alloy steel manufacturing. The top of every spring with screw in the iron frame. The other end, at the bottom of the spring for suspension vibration element (drive assembly and driving clamp).
The vibration head is based on the resonance effect of spring assembly, so the vibration head movement closely with similar pendulum motion.In the spring set system, a spring fixed to its end, the other end connected with the aggregate. If the strike system, system vibration, vibration frequency is a function of the spring mass and stiffness. The spring stiffness is called elastic constant. This frequency is called natural frequency or resonant frequency of the system. In order to make the system work, must to electromagnetic coil alternately applying electric energy. If the natural frequency and the frequency of electric power system applied to match its energy dissipation consumption is the lowest.
The main performance parameters of the vibrating head: Frequency range: 210~250Hz
Vibration range: 0.6~1.8mm
The fixture can drive weight: 30~70kg
Drive plate size: 1000 (L) x 550 (W) mm
Vibration head type: JF-851
Hydraulic system(for hydraulic vibration welding equipment, for servo motor linear vibration welders, it will be servo motor system)
The hydraulic system comprises a hydraulic station and a hydraulic cylinder, hydraulic station by Parker company.。
The hydraulic station is composed of variable axial piston pump, proportional directional control valve, pressure sensor, cooler, filter and a fuel tank.
The main performance parameters:
Tank volume: 25L
Medium: use ISO VG32 high quality anti-wear hydraulic oil The kinematic viscosity at 40℃æ
Motor:2.2kW 1430rpm 50Hz 220V 10A
Variable axial piston pump: 16mL/rev
Maximum working pressure: 20MPa
Normal working pressure: 3~9MPa
Control:proportional pressure control direction
Oil level control
Oil temperature control
Filtration pressure difference control
Hydraulic cylinder: 50mm
Stroke: 500mm
The main function of the hydraulic system is the driving force of the hydraulic cylinder, the lifting worktable is driven to do the vertical direction movement, and can provide a stable pressing force is necessary to two pieces of plastic welding in the welding process.
Drive System
The transmission system comprises a lifting table, two guiding shafts, four linear bearings and a hydraulic cylinder.The lifting table is driven by the hydraulic cylinder, along the guide axis perpendicular to the direction of the rising and falling movement. When welding,the lifting platform is arranged on the lower template, a clamping plastic in the template. Lift movement is determined by the size of the displacement.
Sound ubsulation cover
The soundproof cover shell is made of steel plates, inner lining with sound-absorbing material.
Positive enclosures will also installed an activity called sliding door, security door. The door with 4 wheel and two straight lines the guide shaft installed vertically installed in the enclosures. The stroke is driven by two double acting cylinder. When welding the door is closed. Non welding time, safety door open for assembling and disassembling plastic parts by welding. The inner wall of the safety door also lined sound-absorbing panels, security doors and sound insulation cover is arranged between the sealing material.
Pneumatic System
The pneumatic system by the valve (valve), pneumatic three large, three position five way valve, a one-way
throttle valve, muffler,the cylinder. The pneumatic system is mainly used to drive the safety door of the up
and down movement. The upper and lower limit of safety door the position were determined by two position sensor.The pneumatic system of the air pressure is owned by the user, 0.6MPa.
Safety Devices
Be Careful!
If the Hy-Line vibration welder safety device, the staff of life threatened! If the vibration welder machine maintenance do not take safety measures in the process, you must be very careful. End service immediately after the restoration of security device,and test the role of these safety devices. Only in the work safety device you can operate the linear vibration welding machine.
Emergency Stop System
An emergency stop button on the control panel, second emergency stop button located on the operation box.
Be Careful!
Once the abnormal situation, immediately press the emergency stop button to stop the operation of vibration welding equipment!
Security Door
The safety door is arranged in the front of the unit, a rear door maintenance equipment. The safety door can prevent the operator from welding process contact to the interior of the device, and can isolate noise welding. The automotive vibration welding safety door is by the security door to monitor control.Once the safety door is opened, the lifting platform will be unable to move the safety door closed is controlled by the safety door monitor.
