Since the German Rexroth Indramat (the main supplier of drive and control) introduced the shaftless technology into the printing field for the first time in 1994, due to its own advantages, the shaftless technology has been recognized by the printing industry and gradually It showed a strong development trend, especially in the manufacture of large-scale web offset presses, flexo printing presses, and gravure printing presses.
So what is the shaftless transmission technology? The transmission of traditional printing equipment is based on the gears, shafts and other mechanical parts fixed on the machine to drive the motor power to each unit. The so-called non-shaft technology is to use the (virtual) electronic axis driven by the AC motor to replace the traditional, complex mechanical transmission shaft, and some people therefore call the non-shaft technology Gearless transmission technology. The drive and control of this kind of system uses accurate electronic synchronous digital intelligent servo motor, and the drive of intelligent servo motor which relies on precise synchronous control, instead of the mechanical gear box, vertical axis, cardan shaft which has been widely used so far. And cam. This eliminates the need for additional power, such as a dedicated gearbox or setting up the machine.
What is the reason why the axisless technology has developed rapidly since it entered the printing field? Let us first take a look at some of the advantages that the non-shaft technology has and the traditional mechanical shaft technology cannot replace.
The shaftless drive press is an open structure
Modular design of the independent drive unit. For the shaftless printing press, it is no longer necessary to transmit power to each unit through the spindle, no need to transmit torque through a high-precision gear box, no lubrication system of the gear box, and no inaccurate installation and installation Some of the problems that arise are therefore not caused by gear transmission, which affects the accuracy of overprinting, reduces the noise during operation of the machine, improves the energy efficiency, can make better use of space, and can still be used in some printing units. In operation, the job size of another part of the printing component is changed. At present, most of the non-shaft drive technology adopts a serial port real-time communication system that conforms to the international digital transmission interface standard, and synchronously coordinates each transmission device through a noiseless optical fiber cable, thus simplifying personnel training, product support, and internal production management.
Has a high degree of synchronization and coordination
Each drive unit is a photoelectric signal acquisition and transmission, is done through the noise-free fiber optic cable, no longer use the spindle and the gear box to transmit the force. The synchronization of the tension roller of the drive unit is improved, which provides great convenience for adjusting the speed. Each drive unit has an independent register system. The register control reacts quickly and the control signal acts directly on the AC servo motor. The motor directly acts on the phase of the plate cylinder, which provides a reliable guarantee for rapid response.
Minimize costs. For machine builders, the concept of shaftless drive machines means first and foremost the cost of development, production, and commissioning machines. For the user, compared with the traditional printing machine driven by the motor, the main shaft, the gear transmission pair and the clutch, the shaftless printing press greatly reduces the waste generated due to the influence of the mechanical structure of the printing press, thereby minimizing the waste. cost. As each set of printing units is equipped with pre-registration functions, waste generated during initial registration is reduced. At the time of roll change, due to the driving of the independence of each printing unit, the printing waste produced due to the tension change during roll change is greatly reduced. As the drive system AC servo motor has extremely sensitive dynamic response characteristics and its digital adjustment mechanism, as long as the parameters are changed, it can adapt to the production requirements of different jobs. Traditional printing machines need to change the mechanical structure to meet the production requirements of different jobs. This will not only reduce the machining cost of the machine, but also reduce the non-productive preparation time required to change these structures to a greater extent. The application of the electronic axis allows you to enter only one parameter value, and the digital control system can ensure accurate reprinting, thus reducing the scrap rate and reducing the cost.
flexibility
The shaftless drive press can expand your existing equipment and greatly increase the availability of the equipment. At the same time, due to the modular design unit, the ideal combination of equipment can be achieved, which not only reduces your purchasing costs, but also saves precious resource. The reduction of the transmission mechanism makes it easier for the operator to approach the printing press, and the operation and maintenance are more convenient and flexible. The distance between the printing units is reduced, the material removal distance is short, and the chance of errors is reduced.
Long-distance technical support
With the advent of the Internet era, the distance between enterprises and enterprises has been shortened, and the remote diagnosis and technical services of printing presses have become possible. The application of digital control systems for non-shaft drive printing presses has made this possibility a reality. Whether in any corner of the world, as long as inform the shaftless printing press manufacturing company, almost no problem with your machine, the shaftless printer manufacturer can provide technical services for users, which can minimize downtime time.
If we only look at the mechanism of the printing machine without a shaft, we will also find some obvious advantages.
1. The motor has several million pulses per revolution, which can be used for very precise positioning, better control of the ratio and speed, coupled with intelligent drive and high-speed microprocessor, the control of registration accuracy can be large Increased in magnitude. This type of electronic line shafting (ElS) instead of shaft transmission enables the concept of subunit driving.
The so-called ELS advanced control technology uses an ultra-high resolution encoder (installed directly in the motor) and a high-speed microprocessor to specify the correct position of each axis in the system and reset it accurately.
2. In the use of gears and shaft drive systems, the inevitable torque instability and the lag of the gear will cause the registration to drift, especially when accelerating or decelerating. If more and longer drive shafts, more and more gears, the greater the accumulated error coefficient, this error can be avoided in the new drive and control system. Not to mention the mechanical wear of gears inevitably occurs during use, and the error will increase, and gears are the main factor in the occurrence of streaks (or bars) in printing.
3. Without the rotation of the roller on the gear printing machine, it is no longer limited by the gear pitch. There is no fixed limitation on the repeat length of the printed matter, and it can be arbitrarily adjusted. This is suitable for a flexographic printing machine that requires various specifications of the packaging print. Particularly popular. Just switch the circumference of the plate cylinder to the required one and enter the repeat length data into the control center.
4. In addition to saving high-power drive motors and reducing power consumption, it also cancels a series of mechanical transmission mechanisms, including: plate cylinder, impression roller drive gear, gear box, belt pulley, belt, drive shaft, etc. After the simplification of the structure, the spare parts reserves are drastically reduced, and the maintenance downtime is reduced. Moreover, both the AC servo motor and the synchronous motor are of the brushless type, and the maintenance thereof is simpler and more convenient than the brush type motor.
5. The servo motor and the synchronous motor provide a highly constant torque during the whole operation process. In the case of rapid speed change, the inertia or the hysteresis is low. Therefore, the waste defective product resulting therefrom is greatly reduced. Increased efficiency. Especially in the short-lived situation, it shows its superiority.
In general, the application of shaftless transmission presses will have high productivity and processing quality, great flexibility, high speed product processing speed, simple operation, high transparency, low production cost, and reliable system resources. And processing means to make its users' businesses more rapidly develop.