The history of the invention of machine tools

The name of machine tool was given by Chairman Mao. He said it was the production of machine beds, and later called it a machine tool

A Brief History of Development

1.1 Ancient Tree Machine Tools The emergence of the tree lathe in the second millennium B.C. is the earliest prototype of the machine tool. When working, the foot on the lower end of the rope collar, the use of the elasticity of the tree branches so that the workpiece is driven by the rope rotation, hand holding shells or stone chips, etc. as a tool, along the slats to move the tool cutting workpiece. Medieval elastic rod bar lathe using is still this principle.

1.2 Fifteenth-century prototype machine tools In the fifteenth century, due to the need to manufacture clocks and weapons, the emergence of watchmaker's threaded lathes and gear machine tools, as well as water-driven gun barrel boring machine. 1501 around the time of the Italians Leonardo da Vinci had sketches of the conception of the lathe, boring, threading machine tools, and internal grinder, which already had cranks, flywheels, tips and bearings, and other new mechanisms. New mechanisms such as cranks, flywheels, collar points and bearings were already in place. The structure of the grinder is also contained in the Chinese book Tian Gong Kai Wu, published in the Ming Dynasty, where an iron disk was rotated by means of a foot pedal, and sand and water were added to dissect jade.

1.3 The Industrial Revolution led to the creation and improvement of a variety of machine tools The Industrial Revolution of the eighteenth century gave impetus to the development of machine tools In 1774, the Englishman Wilkinson invented the more precise gun barrel boring machine. The following year, he used this gun barrel boring machine to bore out cylinders to meet the requirements of the Watt steam engine. In order to bore larger cylinders, he built a waterwheel-driven cylinder boring machine in 1775, which contributed to the development of the steam engine. From then on, machine tools began to be driven by steam engines through crankshafts.

In 1797, the British Mozley created a lathe by the screw drive tool holder, can achieve motorized feed and turning threads, which is a major change in the structure of the machine tool. Mozley is also known as the "father of the British machine tool industry".

In the 19th century, due to the textile, power, transportation machinery and munitions production, various types of machine tools appeared one after another. 1817, the British Roberts created a gantry planer; 1818 American Whitney made a horizontal milling machine; 1876, the United States made a universal cylindrical grinder; in 1835 and 1897 and successively invented hobbing machine and gear shaping machine.

The nineteenth century the best mechanical technician should be counted Whitworth, he was made in 1834, the length of the measuring machine, the length of the machine can measure the length of the error of about one ten thousandth of an inch. The principle of this length measuring machine and micrometer is the same, by turning the index plate can be in and out of the thread clamped workpiece, use the slide rule to read out the index on the index plate. 1835, Whitworth at the age of 32 when he invented the hobbing machine. In addition to this, Whitworth designed plug and ring gauges to measure the inner and outer circles of cylinders. It was recommended that all machine tool manufacturers adopt the same size of standardized threads. Later, the British Association for the Development of Industrial Standards accepted this recommendation, and from then until today, this thread is used as a standard thread by all countries.

The center of the development of industrial technology quietly moved from Britain to the United States from the nineteenth century. Among those who took Britain's technological prestige away from it, Whitney was a leader. Intelligent and visionary, Whitney pioneered the development of systems as interchangeable parts for mass production. The Whitney Engineering Company, still active today, developed a turret-type hexagonal lathe as early as the 1840s. This lathe was introduced as workpiece making became more complex and refined, and in this lathe, a capstan is fitted with a winch on which the various tools needed are mounted so that by rotating the turret that holds the tool, the tool can be turned to the desired position.

With the invention of the electric motor, machine tools began to be driven first centrally by electric motors and then extensively by separate electric motors.

In the early twentieth century, in order to process higher precision workpieces, fixtures and threading tools, the creation of coordinate boring machines and thread grinding machines. At the same time in order to adapt to the needs of mass production of automobiles and bearings and other industries, and developed a variety of automatic machine tools, profiling machine tools, combined machine tools and automatic production lines.

1.4 1900 into the precision period of the late 19th century to the beginning of the 20th century, a single lathe has gradually evolved out of the milling machine, planer, grinder, drilling machine and so on, these major machine tools have been basically stereotypes, so that for the first half of the 20th century of the precision machine tools and the production of mechanized and semi-automated to create the conditions.

Within the first 20 years of the 20th century, people mainly around the milling machine, grinding machine and assembly line. Due to the automobile, aircraft and its engine production requirements, in the mass processing of complex shapes, high precision and high finish parts, there is an urgent need for precision, automatic milling machines and grinding machines. Due to the introduction of multi-helix blade milling cutter, basically solved the vibration produced by the single-edged milling cutter and the finish is not high and make the milling machine can not be developed difficulties, so that the milling machine has become an important equipment for processing complex parts.

The world known as "the father of the automobile" Ford, put forward: the car should be "light, strong, reliable and cheap". In order to achieve this goal, must develop high-efficiency grinding machine, for this reason, the American Norton in 1900 with emery and corundum stone made of large diameter and wide grinding wheel, as well as the rigidity of large and solid heavy-duty grinding machine. The development of the grinding machine, so that machinery manufacturing technology has entered a new stage of precision.

1.5 1920 into the semi-automatic period in the 30 years after 1920, machinery manufacturing technology entered the semi-automatic period, hydraulic and electrical components in the machine tools and other machinery gradually been applied. 1938, the hydraulic system and electromagnetic control not only contributed to the invention of a new type of milling machine, but also popularized the use of machine tools, such as the gantry planer. 30 years later. Travel switch - solenoid valve system is used in almost all kinds of automatic control of machine tools.

1.6 1950 into the period of automation after the Second World War, the development of machine tools began to enter the period of automation due to the emergence of numerical control and group control of machine tools and automatic lines. The CNC machine tool is a new type of machine tool that uses the principle of digital control after the invention of the electronic computer to store the machining program, requirements, and the operating digital and text codes for changing tools as information, and to control the machine tool according to the commands it sends out, and to machine the machine according to the established requirements.

1.6.1 The world's first CNC machine tool (milling machine) was born (1951) CNC machine program, is the United States of America's Parsons in the development of checking the profile of the aircraft propeller blade profile of the plate leaf processing machine to the U.S. Air Force, in the Massachusetts Institute of Technology to participate in and assist in the success of the final year in 1949. 1951, they formally made the first electronically tube CNC machine prototype, successfully solved the problem of automation of multi-species small batch processing of complex parts. Later, on the one hand, the principle of numerical control from the milling machine to expand to the milling and boring machine, drilling machine and lathe, on the other hand, from the electronic tube to the transistor, integrated circuits direction of transition. 1958. The United States developed into the ability to automatically change tools for multi-process machining centers.

1.6.2 The birth of the world's first CNC production line (1968) In 1968, the British Maurines Machinery Company developed the first CNC machine tools composed of automatic lines, soon, the United States, General Electric put forward the "factory automation prerequisites is the parts processing of CNC and the production process of the program control "So, by the mid-1970s, the emergence of automated workshops, automated factories have begun to build.

Three technological breakthroughs occurred between 1970 and 1974, as minicomputers were widely used for machine tool control. The first is a direct digital controller, so that a small electronic computer to control multiple machine tools at the same time, the emergence of the "group control"; the second is a computer-aided design, with a light pen to design and modify the design and calculation procedures; the third is the actual situation according to the machining and accidental changes in the feedback and automatic changes in processing and cutting speed, the emergence of self-adaptive control system machine tools. The emergence of self-adaptive control system machine tools.

After more than 100 years of wind and rain, the family of machine tools has become increasingly mature, and really become a mechanical field of "workhorses".