A, CNC machine tools has the following prominent superiority than traditional machine tool, and these advantages are from the NC system includes computer power.
Complex 1.1 can be processed by conventional machining is not the curve, surface and other parts.
Because the computer has excellent operation ability, can be accurately calculated instantaneous each axis of instantaneous should the amount of exercise movement, it can compound into complex curves or surfaces.
1.2 automated processing can be achieved, but also flexible automation, thus the efficiency can be increased by 3 ~ 7 times than that of traditional machine tool.
Because the computer memory and storage capacity, can be imported and stored procedures remember down, and then press the procedural requirements to implement the order automatically, thus achieving the automation. CNC machine tool as a replacement procedures, automation can be achieved another workpiece processing, so that the single piece and small batch production can be automated, it has been called "flexible automation".
1.3 processing of high precision parts, size dispersion degree is small, easy to assemble, no longer need to "repair".
Concentration of 1.4 can achieve more processes, reducing the frequent handling at machine parts.
1.5 from the above five derived benefits. Such as: reduces the labor intensity of the workers, save the labor force (a person can look after more than one machine), a decrease of tooling, shorten the product development cycle and the production cycle, can quickly respond to market demand and so on.
These advantages are our predecessors can not imagine, was a major breakthrough. In addition, NC machine tools is the implementation of FMC (flexible manufacturing cell), FMS (flexible manufacturing system) and CIMS (Computer Integrated Manufacturing System) based enterprise information-based transformation. Numerical control technology has become the core technology and basic technology of manufacturing automation.
Two, the NC transformation of the content
2.1 to restore the original function, the fault of machine tool, the production line are diagnosis and recovery;
2.2 CNC, digital display device is added in the general machine tool, or NC system, transformed into NC machine, CNC machine tool;
2.3 renovation, in order to improve the precision, efficiency and automation of electrical parts, mechanical, refurbished, re assembly of mechanical parts processing, to restore the original accuracy; on the do not meet the production requirements of the CNC system is updated to the latest cnc;
2.4 updating of technology or technological innovation, to improve performance or quality, or to the use of new technology, new technology, greatly improve the renovation grade level and on the basis of the original.
Three, the characteristics of NC transformation
3.1 less investment, short delivery time
Compared with the purchase of new machine, the general can save 60% to 80% of the cost, low modification cost. Particularly large, especially special machine tool. General large-scale machine tools, only to spend the cost of the new machine purchase 1/3, short delivery time. But in some special cases, such as the manufacture and installation of automatic switching device of high speed spindle, tray, a great deal of money, often raise the cost of 2 to 3 times, compared with the purchase of new machine, can save investment 50%.
3.2 mechanical properties of stable and reliable, the structure is limited
By the use of bed, column and other basic items are heavy and solid casting components, not the kind of welding components of the machine after the high-performance, good quality, can continue to use the new equipment for many years. But by the mechanical structure of the original limit, not to do the transformation of a breakthrough.
3.3 familiar with the equipment, convenient operation and maintenance
The purchase of new equipment, do not understand the new equipment whether can meet the processing requirements. Transformation is not, can accurately calculate the machine processing capacity; in addition, due to many years of use, operator of the machine has long been understood, training in operation and maintenance time is short, quick. Transformation of the machine tools installed, you can achieve full load operation.
3.4 can make full use of the existing conditions
Take full advantage of the existing foundation, not like buying new equipment as necessary to build a foundation.
3.5 can be used to control the latest technology
According to the development speed of technological innovation, in a timely manner to improve the automation level and efficiency of production equipment, improve equipment quality and grade, the old machine will be replaced by the current level of machine.
Four, the choice of numerical control system
CNC system there are three main types, transformation, should be chosen according to the specific situation. 4.1, stepping motor drive the open-loop system (meet the needs of most of the cheap price of machine tool transformation. )
The servo drive system is a stepper motor, stepper motor power, such as electro-hydraulic pulse motor. Pulse feed NC instructions sent by system, controlled by a driving circuit and power amplification, the stepper motor rotate through the gears with ball screw drive execution unit. As long as the controlling quantity and instruction of the pulse frequency and the order of power, can control the displacement, the execution component motion velocity and direction of motion. This system does not need to be measured by the actual position and velocity feedback to the input, so called open-loop system, this system displacement precision mainly decided to angular displacement precision stepper motor, gear screw transmission element pitch precision, so the system displacement precision is low.
The system has the advantages of simple structure, convenient adjustment and maintenance, reliable work, low cost, easy modification of success.
4.2, asynchronous motor or a DC motor drive, grating measurement feedback closed loop control system
4.3, AC / DC servo motor drive, half closed loop control system with encoder feedback |
|
