XI Международная студенческая научная конференция Студенческий научный форум - 2019

Studying machine tools and tools, I read about universal machines that can work without an operator, namely about machine tools with numerical control. And I had a question: how has the mechanical engineering industry changed after the introduction of CNC machines?

The development of numerical program control (CNC) has approximately thirty years of history. The founder of the CNC system is considered to be John. T. Parson, professor at the Massachusetts Institute of Technology. In the late 1940s he developed equipment for encoding a control program on metal punch cards. The program controlled the milling machine feed drives.

In 1948 this system was put into operation in the US military aircraft industry. The beginning of the mass operation of CNC machines can be attributed to the end of the 1950s of the 20th century. In the 21st century in most developed countries the annual production of CNC machines exceeds 50%. In Japan this figure is more than 85%.

A controlled machine is commonly understood to be a set of effects on its mechanisms that ensure the execution of a technological processing cycle, and a control system is a device or set of devices that implements these effects. Numerical control (CNC) is a control in which a program is set as an array of information recorded on a medium. Control information for CNC systems is digital. Technological cycles are controlled by programmable logic controllers. CNC systems are almost ousting other types of control systems.

Devices of CNC machines are made on the basis of microprocessor platforms that are compatible with computers, control programs are used as information carriers that are read by the machine and they program it to perform specified operations.

In general, the structure of the “CNC machine” complex can be represented in the form of three blocks, each of which performs its own task: control program (UE), CNC device (CNC) and the machine itself. All the blocks of the complex work are interconnected in a single structure.

The development of CNC machines creates high-performance technological modules, which include: a multi-operational machine with automatic tool change, a transport-storage system that allows replacement of the part with a workpiece, a system for controlling and regenerating waste. Such modules can operate in standalone mode or can be integrated into automatic lines. CNC machines allow machining parts with a large concentration of tool transitions, which improves the accuracy of parts (machining from one technological base), reduces the time for operation and reduces the length of transport flows.

Thus, the share of CNC equipment in the production of all areas is growing from year to year. Today, no one needs a simple machine. CNC is an integral part of any machine. This is due to large economic indicators: a significant reduction in staff and an improvement of the quality of products. In addition, in large industrial enterprises where CNC machines are used in large quantities, the combined control of all machines from a single dispatch console is possible.

Based on the development history of machine tools in machine building, their modernization and improvement to automatic machines and semi-automatic machines, new intelligent generation machines equipped with CNC systems, working according to a given control program, performing the perfectly necessary operations for manufacturing parts of different types and accuracy from materials of different strengths, while the control program is stored in the machine's memory and, if necessary, processing of similar parts is corrected for them and starts up again.

The use of CNC machines is especially appropriate for mass production (i.e., the machine performs a huge number of parts for one already given UE). Accuracy and compliance with the required dimensions are guaranteed, which leads to an improvement in the quality of manufactured products and an increase in value and demand, as well as a corresponding reduction in the cost of unit cost, since there is no need for a personal operator with a high level of qualification for each machine; a single operator can work on three or more CNC machines.

References

1. “Силовая электроника: от простого к сложному“. Семенов Б.Ю., 2005 г.

2. “Разработка программного обеспечения для систем управления электрическими двигателями". А.С. Каракулов, Д.С. Аксенов, Б.В. Арещенко, В.С. Саидов, 2007 г.

3. “Микропроцессорное управление технологическим оборудованием микроэлектроники” А.А. Сазонов, 2001 г.

4. “Машиностроение". Григорьев С.Н., Кохомский М.В., Маслов А.Р., 2006 г.