A machine tool, also known as a fabrication machine or machine tool machine, refers to a machine used for manufacturing other machines.
It can be classified into three categories: metal cutting machine tools, forging machine tools, and woodworking machine tools.
According to Wikipedia, a machine tool is defined as a machine used for shaping or machining metal or other rigid materials through processes such as cutting, boring, grinding, shearing, or other forms of deformation.
There are many methods for machining mechanical parts in modern machinery manufacturing, including cutting, casting, forging, welding, stamping, and extrusion. However, for parts with high precision and surface roughness requirements, cutting on a machine tool is typically used for final processing.
Machine tools play a crucial role in the modernization of a nation’s economy.
One example of a machine tool is a lathe, which primarily rotates the workpiece while using a turning tool to shape it. Other tools such as drills, reaming drills, reamers, taps, dies, and knurling tools can also be used in a lathe to complete various processing tasks.
The lathe is primarily used to machine shafts, plates, sleeves, and other workpieces with rotating surfaces. It is the most commonly used machine in machinery manufacturing and repair plants.
Machine Tools Development History
The prototype of the machine tool emerged in the 15th century due to the need for the manufacture of watches and weapons. The first machine tools included the watchmaker’s lathe, gear machining machine, and water-driven barrel boring machine.
In 1501, Italian inventor Leonardo da Vinci created sketches of lathes, boring machines, threading machines, and internal grinders, including new innovations such as cranks, flywheels, tops, bearings, and more. The Ming Dynasty’s “Heavenly Creations” also contained descriptions of grinders, which used pedals to rotate iron plates and used sand and water to cut jade.
The industrial revolution further led to the creation and improvement of various machine tools. During the 18th century, the industrial revolution greatly contributed to the development of machine tools. In 1774, British inventor John Wilkinson created a more advanced barrel boring machine. The following year, he used this machine to bore cylinders for Watt’s steam engine. To bore larger cylinders, Wilkinson also created a water wheel-driven cylinder boring machine in 1775. This marked the beginning of steam engines driving machine tools through crankshafts.
In 1797, British inventor Henry Maudslay made significant changes to the structure of machine tools by creating a lathe with a screw-driven tool holder, which allowed for motor feed and thread turning. Maudslay is considered the “father of the British machine tool industry.
In the 19th century, the promotion of textile, power, transportation machinery, and arms production resulted in the emergence of various types of machine tools.
In 1817, British inventor Roberts created the gantry planer and in 1818, American inventor Eli Whitney developed the horizontal milling machine. In 1876, the United States made the universal cylindrical grinder and hobbing machine and gear shaper were invented in 1835 and 1897 respectively.
From the 19th century, the center of industrial technology development shifted from the United Kingdom to the United States. Among the British technology leaders, Whitney stands out for his intelligence and vision. He was the pioneer of a system for replacing parts and large-scale production. The Whitney Engineering Company, which is still active today, successfully developed the turret hexagonal lathe in the 1940s. This lathe was designed for the complexity and refinement of workpieces and was fitted with a winch that held all the necessary tools. By rotating the turret, the tool could be transferred to the desired position.
With the invention of the motor, machine tools started to use motor drive, and eventually separate motor drive became widely used. At the beginning of the 20th century, to process workpieces, fixtures, and thread processing tools with higher precision, the coordinate boring machine and thread grinder were created. At the same time, to meet the needs of the automobile and bearing industries and other large-scale productions, a variety of automatic machine tools, copying machine tools, combined machine tools, and automatic production lines were developed.
The 20th century marked the period of precision in machinery manufacturing.
From the late 19th century to the early 20th century, single lathes evolved from milling machines, planers, grinders, drilling machines, and other main machine tools, which created the conditions for precision machine tools and production mechanization and semi-automation.
During the first two decades of the 20th century, attention was focused on milling machines, grinders, and assembly lines. The demand for sophisticated and automatic milling machines and grinders for large quantities of complex, high-precision, and high-quality parts arose due to the requirements of automobile, aircraft, and engine production.
The advent of the multi-helix cutter resolved the difficulties in the development of milling machines, which were caused by the vibration and low smoothness of single-blade cutters. This made milling machines an important piece of equipment for complex parts. Henry Ford, known as the father of the car, stated that “the car should be light, strong, reliable, and cheap,” and efficient grinding machines were needed to achieve this goal. To meet this need, the United States’ Norton created a large diameter and wide grinding wheel made of corundum in 1900 and a heavy grinding machine with high stiffness and strength.
The development of grinding machines marked a new stage of precision in machinery manufacturing technology. In 1920, the semi-automated period began. During the 30 years since 1920, machinery manufacturing technology entered a semi-automated period, and hydraulic and electrical components were gradually applied to machines and other machinery.
In 1938, the introduction of hydraulic systems and electromagnetic control not only led to the invention of new milling machines but also the widespread use of gantry planers and other machine tools. Thirty years later, trip switch-solenoid valve systems were used in a variety of machine automatic controls.
In 1950, the automation period began. After World War II, the development of machine tools entered the automation period due to the emergence of CNC, group control machine tools, and automatic lines.
CNC machines use the principle of digital control, storing processing procedures, and requirements, and replacing the operation of tools with digital and text codes. The machine is controlled according to these instructions and processes according to established requirements.
The world’s first CNC machine tool (a milling machine) was invented in 1951. The CNC machine tool program was developed by John Parsons for the R&D of aircraft propeller blade processing machines and profile inspection with the assistance of the Massachusetts Institute of Technology. In 1951, they officially created the first tube CNC machine tool prototype and successfully solved the automation problems of multi-species small batch complex part processing.
Later, the principle of numerical control was applied from milling machines to milling and boring machines, drilling machines, and lathes, and from tubes to transistors and integrated circuits. In 1958, the United States developed a tool for automatically replacing the tool for multi-process processing centers.
The world’s first CNC production line was created in 1968 by the British Maulinsi machinery company, which developed the first CNC machine tools composed of automatic lines.
Soon after, the United States General Electric Company proposed that “factory automation is a prerequisite for CNC parts processing and program control of the production process.” By the mid-1970s, with the emergence of automated workshops and factories, there were three technological breakthroughs in machine control due to the widespread use of small computers.
The first was the direct digital controller, which allowed a small computer to control more than one machine at the same time, leading to “group control”.
The second was computer-aided design, which used a light pen to design, modify designs, and calculate procedures.
The third was an adaptive control system machine that could change processing and cutting speed based on actual processing conditions and unexpected changes, and provide feedback.
After a hundred years of ups and downs, the machine tool family has become increasingly mature and has truly become the “working machine” in the machinery field.
Common types of machine tools
Lathe
Ancient pulleys and bow-shaped “bow lathes”
As early as ancient Egyptian times, people invented turning technology by rotating wood around its central axis for cutting purposes. They used two stands as a support, placed the wood for turning, and used branches’ elasticity to roll the rope around the wood. They rotated the wood by hand pulling or pedal pulling the rope and held the tool for cutting.
This ancient method evolved into winding two to three circles of rope on pulleys and imposing the rope on the curved arch-shaped elastic rod, which rotated the processing object by pushing back and forth. This is the “bow lathe.”
Medieval crankshaft, flywheel-driven “lathe”
By the middle of the century, a foot pedal was used to rotate the crankshaft and drive the flywheel, which then rotated the spindle on the “lathe.”
In the mid-16th century, a designer named Besson in France designed a lathe that used a screw to slide the tool with a screwdriver, but unfortunately, the lathe was not used.
Eighteenth-century bedside box and chuck
By the 18th century, the foot pedal and connecting rod were used to rotate the crankshaft, which could turn the kinetic energy stored in the flywheel on the lathe. The direct rotation of the workpiece was changed to rotary bed box, which was a chuck used to hold the workpiece.
Britishman Mozzley invented the turret lathe (1797)
In the history of lathe invention, the most notable figure is a British man named Mozzley, who invented the epoch-making turret lathe in 1797, equipped with a precision lead screw and interchangeable gear.
The birth of various special lathes aimed to improve the degree of automation.
In 1845, the United States’ Fitch invented the turret lathe, and in 1848, the drum lathe appeared in the United States.
In 1873, the United States’ Spencer made a single-axis automatic lathe, and soon after, he created a three-axis automatic lathe.
At the beginning of the 20th century, a lathe with a gearbox was driven by a separate motor, and with the invention of high-speed tool steel and the application of motors, the lathe was improved to reach a modern level of high speed and high precision.
After World War I, various efficient automatic lathes and specialized lathes developed rapidly to meet the needs of the arms, automobile, and other machinery industries.
To improve productivity for small batches of workpieces, hydraulic profiling lathes were promoted in the late 1940s, and multi-tool lathes were also developed.
In the 1950s, program-controlled lathes were developed using punch cards, plug plates, and dial pads.
CNC technology was introduced to lathes in the 1960s and rapidly developed in the 1970s.
Classification of lathes
Lathes are classified into various types based on their usage and functions. The conventional lathe is versatile in terms of the workpiece it can process and has a large spindle speed and feed adjustment. It can perform internal and external threading and is mainly operated by hand, making it suitable for single or small-batch production and repairs in shops.
The turret lathe and rotary lathe have a turret or reel tool holder that can hold multiple tools and can perform various processes in succession, making it ideal for mass production. The automatic lathe can perform multiple processes automatically for small to medium-sized workpieces and can automatically load and unload for mass production of the same workpiece.
The multi-tool semi-automatic lathes can be single or multi-axis and can be horizontal or vertical. The single-axis horizontal type is similar to a conventional lathe but has two sets of tool holders mounted on the front or rear of the spindle, making it three to five times more productive than a conventional lathe.
The profiling lathe can be modeled after a template or sample and automatically completes the machining cycle of the workpiece, making it suitable for small batches and complex parts. This type of lathe is 10 to 15 times more productive than a conventional lathe and comes in multi-axis, chuck, and vertical varieties.
The vertical lathe has a vertical axis perpendicular to the horizontal plane and the workpiece is clamped on a horizontal rotary table. The tool holder moves on a beam or column, making it suitable for larger and heavier workpieces that are difficult to install in a conventional lathe. It can be single-column or two-column.
The scissor lathe has a periodically reciprocating tool holder and is used for forming tooth surfaces on forklift cutters and hobs. It is usually equipped with a milling tool and a small grinding wheel driven by a separate motor.
Special lathes are designed for specific surfaces of certain types of workpieces such as crankshaft lathes, camshaft lathes, wheel lathes, axle lathes, roll lathes, and steel lathes. The combined lathe is mainly used for turning but can also perform boring, milling, drilling, tapping, grinding and other processes, making it ideal for repair work on construction vehicles, ships, or mobile repair stations.
Boring machine
The handicraft industry in the factory, although relatively backward, has trained and produced many skilled craftsmen. Despite not being experts in machine manufacturing, they are capable of making a variety of hand tools, such as knives, saws, needles, drills, cones, grinders, shafts, and various types of gears and bed frames.
The parts they create are used in the assembly of machines. The first designer of the boring machine was Leonardo da Vinci, and it is referred to as the “mother of machinery.”
Da Vinci is considered the first designer of the boring machine for metalworking. He designed the machine to be powered by water or pedals, with the boring tool rotating close to the workpiece, which was fixed in a crane-driven mobile station. In 1540, another painter depicted a similar boring bed in his “fireworks” painting.
The boring machine was used to finish hollow castings. The first boring machine for the processing of cannon barrels was invented by Wilkinson in 1775. In the 17th century, military needs led to the rapid development of the cannon manufacturing industry, and finding a solution for producing cannon guns became a pressing issue.
Wilkinson’s boring machine was the first real boring machine in the world. It was a precision drilling machine for machining cannon barrels and was a hollow cylindrical boring bar with bearings installed at both ends.
Wilkinson was born in the United States in 1728 and moved to Stafford County, the location of Billston’s first iron furnace, when he was 20 years old. He was referred to as the “Master Blacksmith of Staffordshire.”
In 1775, at the age of 47, Wilkinson finally succeeded in creating a rare precision drill for cannon barrels through tireless efforts at his father’s factory.
Interestingly, after Wilson’s death in 1808, he was buried in a cast iron coffin.
The boring machine made a significant contribution to James Watt’s steam engine. Without the steam engine, the first wave of the industrial revolution would not have been possible.
The development and implementation of the steam engine was not only due to necessary social conditions, but also technical prerequisites. To manufacture the parts of the steam engine, specialized metal shapes with high precision were required, which could not be achieved without the appropriate technical equipment.
For example, the steam engine cylinder and piston required accurate dimensions. The outer diameter of the piston could be cut from the outside margin, but achieving the required accuracy in the diameter of the cylinder was not feasible with conventional processing methods.
Smith was the best mechanical technician of the 18th century. He designed 43 sets of water tankers and windmill equipment.
The most challenging aspect of steam engine production was processing the cylinder. It was difficult to create a large, smoothly rounded inner circle.
To overcome this challenge, Smithton created a special machine for cutting cylinders at Karen Iron Works. This boring machine was powered by a water truck and had a tool attached to the front end of its long axis that could be rotated within the cylinder to process its inner circle.
However, because the tool was attached to the front end of the long axis, there was a risk of shaft deflection. As a result, processing a truly round cylinder was very difficult, and Smithton had to change the position of the cylinder multiple times during processing.
In 1774, Wilkinson solved this problem with his invention of the boring machine. This machine used a water wheel to rotate the material cylinder while aligning it with a fixed, centered tool. The relative movement between the tool and the material allowed for the material to be bored with a cylindrical hole with high precision.
At the time, using a boring machine to make a 72-inch diameter cylinder with an error that did not exceed the thickness of sixpence coins was considered a remarkable achievement. By modern standards, this may seem like a large error, but given the conditions at the time, it was a significant progress.
However, Wilkinson did not patent his invention, and it was widely copied and installed by others. In 1802, Watt mentioned Wilkinson’s invention in his book and imitated it at his Soho iron factory. Later, Watt used Wilkinson’s machine in the manufacture of the steam engine cylinder and piston.
Originally, the size of the piston could be measured while cutting from the outside. However, this was not possible for the cylinder and required the use of a boring machine. At the time, Watt used a water wheel to rotate the metal cylinder so that the center of the fixed tool could cut the inside of the cylinder. This resulted in a cylinder with a diameter of 75 inches that had an error of less than the thickness of a coin. This was a remarkable achievement at the time.
The Workbench Lifting Boring Machine was born (Hutton, 1885). In the following decades, many improvements were made to Wilkinson’s boring machine. In 1885, the British engineer Hutton created the table-lifting boring machine, which became a prototype for modern boring machines.
Milling machine
A milling machine is a machine tool that uses a milling cutter to process various surfaces of a workpiece. The main movement of the milling machine is the movement of the milling cutter, while the movement of the workpiece is the feeding movement.
Milling machines are versatile tools that can be used to process flat surfaces, grooves, gears, and a variety of other shapes. They are more efficient than planers and are widely used in machinery manufacturing and repair departments.
In the 19th century, the British developed boring machines and planers to meet the demands of the industrial revolution, such as for steam engines. Meanwhile, the Americans focused on inventing milling machines to produce large quantities of weapons.
A milling machine can cut into a workpiece to create special shapes, such as spiral grooves and gears, using different shaped milling cutters. The earliest known milling machine was created by British scientist Hook in 1664, which involved cutting using a rotating circular tool. However, it did not receive widespread recognition at the time.
In the 1940s, Pratt designed the so-called Lincoln milling machine. However, the real establishment of the milling machine in the machine manufacturing industry is credited to American inventor Whitney.
Whitney is credited with creating the world’s first ordinary milling machine in 1818, although the patent for the milling machine was granted to British inventor Bodmer in 1839.
Due to the high cost of milling machines, there was limited interest in the invention at the time.
After a period of inactivity, the development of milling machines resumed in the United States. Whitney and Pratt made significant contributions to the invention of the milling machine, but the true credit for the creation of a factory-operable milling machine belongs to American engineer Joseph Brown.
In 1862, Brown created the world’s first universal milling machine, which was a significant milestone in the industry. The universal milling machine featured a table that could be rotated in a horizontal direction and came equipped with a vertical milling head and other accessories.
Brown’s universal milling machine was displayed at the Paris Fair in 1867 and was a huge success.
At the same time, Brown also designed a milling cutter that would not deform after grinding and created a grinding machine to sharpen the cutter. This development brought the grinding machine to its current level of capability.
Planer
In the invention process, many things often complement and interlock each other. The invention of the steam engine led to the development of machine tools, including boring machines, lathes, and planers.
A planer is a machine used for shaping metal.
The development of the grand plane planer (1839) was a result of the need to machine steam valve seats. Starting from 1814, many technical professionals, including Richard Roberts, Richard Pratt, James Fox, and Joseph Clement, began researching this issue. Over the course of 25 years, each of these individuals independently created a planer.
The gantry planer processed objects that were fixed on a reciprocating platform and cut one side of the metal. However, this planer lacked a cutting tool, which was crucial for the mechanical conversion process. In 1839, a British man named Bodmer finally designed a planer with a cutting tool.
In the following 40 years starting from 1831, Smith invented the small plane planing machine, which could fix fabricated material on a bed and had a reciprocating tool movement. Since then, with the improvement of tools, the emergence of motors, and the development of gantry planers, the planing machine has become more efficient, precise, and large-scale.
Grinder
Grinding is an ancient technology that has been known to humans since prehistoric times. In the Paleolithic era, grinding stones were used in this technology. The use of metal equipment later propelled the development of grinding technology.
However, the design of a true grinding machine only appeared in modern times. Even in the early 19th century, people were still using natural grinding stones by rotating them to process objects.
The first grinder was invented in 1864 by the United States. It was a lathe with a grinding wheel mounted on a slide plate and provided with a means for automatic transmission. Twelve years later, the United States invented a universal grinding machine that was similar to a universal grinder.
The demand for artificial grinding stones also rose. In 1892, American Acheson successfully developed silicon carbide abrasive stones from coke and sand, which is now known as a C abrasive artificial stone. Two years later, an abrasive with alumina as the main component was successfully developed, expanding the application of the grinding machine.
With further improvement in the bearing and guide parts, the precision of the grinding machine has continued to increase, leading to the development of various specialized grinding machines, including internal grinding machines, surface grinders, roller grinding machines, gear grinding machines, and universal grinding machines.
Drilling machine
The Ancient Drilling Machine – “Bow Windlass” – has a long history in drilling technology. Archaeologists have found evidence that humans invented a punch with a device as far back as 4000 BC.
In those days, a beam was placed on two columns and a rotating cone was hung from it. The cone was rotated by winding a bowstring, allowing the punch to be used on wood and stones. Soon after, people designed punching devices known as “windlasses” that also used a flexible bowstring to rotate the awl.
The first drilling machine was invented by Whitworth in 1862. By 1850, the Germans had created the metal twist drill. At the international fair held in London in 1862, Whitworth exhibited a power-driven cast iron cabinet drilling machine, which became the prototype of modern drilling machines.
Later, various types of drilling machines were invented, including radial drilling machines, drilling machines with automatic feed mechanisms, and multi-axis drilling machines that could drill multiple holes at the same time. With the improvement of tool materials and bits and the use of electric motors, high-performance, large-scale drilling machines were finally manufactured.
CNC machine tools
A CNC machine is an automated machine with a program control system. The control system is capable of logically processing a program with control code or other symbol instructions and decoding it. This allows the control unit to operate and monitor the movement and processing of the machine tool, all of which are completed within the numerical control unit.
The numerical control unit serves as the brain of the CNC machine tool.
Crankshaft machine tools
The crankshaft high-efficiency specialized machine also has its own processing limitations. Only by applying the appropriate processing machine in a rational manner can the efficiency and specialty of the crankshaft machining machine be fully utilized, thus improving the processing efficiency of the process.
Forging machine tools
The forging machine is a type of cold work equipment used in metal and mechanical fabrication. It only alters the shape of the metal.
Examples of forging machine tools include roll bending machines, plate cutting machines, stamping presses, presses, hydraulic presses, and press brakes.
