Control of the machine what is it ? Machine commands performs work that contributes to the implementation of certain actions and perform certain processing (said exaggerated, but captures the essence).
Programming CNC machine is a process during which, the machine receives a task for processing of any products. This task (program) is loaded (installed) to the system equipment (rack CNC).
the System provides operation this task is called a control system of the CNC. The process of entering this program into the rack is populated with various electronic media, different drives, or floppy USB media, magnetic tapes, and all kinds of paper tape(punch cards) .
Control mechanisms of the machine can occur by points marked on the coordinate machine. Coordinate of the point is responsible for the location of the tool (actuator) after certain manipulations. This method is used on drilling, jig boring, boring machines using a POS system.
If you use trajectory to move the actuators without breaking the contour of the trajectory, this method is called «continuous control system» or contour. It is used on grinding, milling and turning machines.
But in the same system. allows for the combination as a contour or points together. Combination combination is called universal. And apply to machines combining milling, turning, drilling operations together.
multi-purpose machines with a versatile CNC system
There is an option to control several mechanisms and components of the machine immediately. This type of machine control is applied to a centerless cylindrical grinding machines.
the location of the coordinate system in CNC machines can be determined by right-hand rule (thumb indicates the position of the X-axis, the index finger indicates the axis Y middle finger indicates that the axis Z .
as the input of the program is different from each other. Enter of the control program directly on the machine in the manufacture of the first batch of parts or fabrication of the experimental sample. The program input may be outside the location of the machine via a computer network.
control of electric circuits of the machine answer programmable controllers . This design consisting of several modules. (power supply, programmable memory and CPU block, various modules of inputs and outputs. Supervisors have different types of memory for program storage of the machine. Also, the controller diagnoses the errors in the CPU, battery, memory, inputs and outputs.
control Software is from cyclic and numerical control.
Considering the cyclic system see that the system is simple. It programs a series of processing, the processing mode, the tool change specifies the amount of moving parts of the machine (the Executive) using the limiter stops.
Cyclic system is a closed circuit capable of changing the power-on sequence of the instrument. Electrical, hydraulics, Pneumatics can be switched on at a time. The system is not complicated in design, simple in service is low cost, but time consuming in the dimension setup stops and Cams. Used in repetitive, high-volume, mass production. Used on milling, turret lathe, vertical drilling machines and aggregate.
number system and geometry move by using the native program (specified in an alphanumeric code). The program is responsible for the movement of the Executive bodies, the speed of movement of these bodies, the sequence of the processing cycle cutting data.
Universal CNC system
They are used on different machines while still providing all types of interpolation. Linear, circular, parabolic, etc .
Main operation mode of the device of the CNC — automatic mode .
With the help of programmamatically program is set for working Executive. Programmedical contains technological and geometrical information. Technological information includes information on the sequence of commissioning of different instruments, changing the cutting conditions, coolant. The geometric information is responsible for configuration of parts, dimensions , the position of the tool in space.
Especially the performance of various mechanical processing on CNC machines
With the advent of high precision requirements of manufacturing parts, quality of surfaces, high roughness and increase a wide range of parts led to a massive substitution of universal lathes machines equipped with CNC.
CNC Machines capable of manufacturing the most complex of parts, regardless of complexity, configuration, and demand for high quality products. Such equipment has very high performance. Which allows to obtain a smooth high-quality products. Which means that if you use CNC equipment we need as many as possible to make maximum use of its technical capabilities, when designing the technological process it is necessary to take into account the capabilities and limitations of the equipment. When using CNC machines, the machining of the part extends across the spectrum: turning, milling, drilling. Various boring internal and external surfaces.
chamfer and tapping of different threads, countersinking, reaming, everything is possible on this machine in the solution of complex problems. Excluding the locksmith further improvement. Because the machine equip with tool adjustment with a list of all tools needed for the manufacture of certain items, like cutting and auxiliary tools can be standard and special production. When turning the CNC allows for single setup of the part to produce: exterior rough, interior rough, further exterior and interior finishing, threading, parting. To handle the body of rotation of a multi-stage shape and configuration.
with regard to CNC mills, they have a huge advantage over other milling equipment. Milling machines are considered to be the most popular equipment at the moment, regardless of industry application, whether as metal processing and wood processing. All furniture production is completely dependent on milling machines.
With the advent of CNC it has been possible to process such new materials as MDF and wood of various species and in different degrees of hardness. There is a possibility to handle 3D thread. Machines are very easy to control, programming and debugging. Details have maximum precision in size, as there may be many coordinate processing. High-speed machines with long working life.
On milling machines with multi-axis simultaneous vertical and horizontal, milling various ledges, ledges with the use of VOSTOCHNOGO and the end of the tool. When performing engraving work the main advantage of these machines is high speed and precision.
the advantages and disadvantages of various types of technological equipment with CNC
Machines of the previous generation not having a control system had disadvantages such as not precision in processing, not accuracy in dimensional proportions. The machine had a large enough kinematic scheme. Labor was exhausting process, as the production demanded increased attention from the staff. With the advent of CNC manufacturing has fundamentally changed its structure. In place of several models of machines in their place came single machining center with CNC. Reduced the number of workers on the machines. So a basic workflow performs the machine itself, and the man has mostly serving an auxiliary function. That fundamentally reduces the complexity of the production process. Faster was the adjustment of the machine, which really sped up the production process. But the CNC equipment has evolved over time.
Modern machines have come a very long way of evolution from the NC tape, passing the tape system with built-in memory and up to all sorts of systems, circuits, and information programming which is hosted on a mini USB media. And mechanical equipment at the machine is also changed. As CNC system demanded high precision from the machine, then all the nodes ,all the components of the lathe spindles, work tables, gears, guides, must meet the new standards to ensure appropriate quality standards for CNC machining. It all revealed that the specified complexity in the manufacture of parts only justifies the very system of the CNC. The more complex and, more detail is required on the output, the more necessary equipment with CNC.
One of the main advantages of CNC is the ability to fast for a drastic adjustment of production to another product line, without spending much from the economic point of view and human resources. That surpasses the main and almost the only disadvantage of CNC is its high cost, which in General is no longer a drawback because the high price is quickly justified. Even the high skilled training of working personnel is not a disadvantage, quite the contrary contributes to the quality of the equipment.
Principles of selection the type and model of process equipment
To select the type and model of process equipment, it is necessary to determine the type of production, rate of production per year, the quantity and quality of products.
There are 5 types of production, and under each type, you can choose certain technological equipment. The production type is characterized by the rate of release, quantity per year and a weight, per garment.
- Unit production series up to 5 pieces with weight up to 10 kg. Average from 5 to 100 pieces, and weight from 10 to 100 kg. Heavy series up to 10 pieces weight from 100 kg.
- limited production series of 5 to 100 pieces and weight up to 10 kg. mid-range from 100 to 500 pieces, and weight from 10 to 100kg. Heavy from 10 to 200 pieces, with weight from 100kg.
- Medium-batch production series of 100 to 300 pieces and weight up to 10 kg. the Average of a series from 500 to 5000 pieces, and weight is from 10 to 100kg. Heavy from 200 to 500 pieces, with weight from 100kg.
- large-scale production series of 300 to 1000. Average from 5000 to 50000 . heavy from 500 to 5000 with the same mass .
- Multi — series easy 1000 . Average of 50000 . Heavy 5000 with the same mass .
Further, we define the processing technology, considering the quality, the accuracy of the surface type of the workpiece. After all enabled moments of an economic issue, performance, cost. Take into account the production cycle, technological requirements imposed on the equipment. And after all the questions choose the production type and under it is determined by the type of equipment that is able to satisfy the range of production.
Possible malfunctions of CNC systems
For the maintenance of CNC equipment in the company, granted special service (service), usually the manufacturer provides service. So as the factory is organizing a training program on the issue of commissioning and further operation of the equipment. The company supplying equipment is required to provide the documents, in the form of a technical passport of the machine, the manual, information on the causes and remedies. Can provided samples of programs for testing the machine that shows that the equipment has no faults and is ready for use.
Test machine is built so that the check occurred gradually, the elements of the machine’s performance. This method of construction provides a fast search resulting malfunction. First machine is maintained by the coordinate (displacement) . Next, it is checked according to the amounts of linear, circular interpolation, over all input modes. Checked the function of the work (supply , drainage) coolant, etc.
since the failure of health happen unexpectedly, failure of the unit chip or module, the gap and circuit the individual circuits, poor conduction of the various of the connector contacts to avoid malfunctions periodically run a test program, if a problem is detected, the malfunction is corrected by experts. The duration of the repair depends on the nature of the fault If the item or block interchangeable the repair occurs without significant loss of production.