Understanding the term \"machine\"

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①Various devices constructed using mechanical principles. Levers, pulleys, machines, and guns are all mechanical devices. ②The metaphorical approach is rigid and lacks variation ； It’s not dialectical: the working method is too ~. The word \"machine\" derives from the Greek word \"mechine\" and the Latin word \"mecina\"; it originally referred to a \"clever design\". As a general concept relating to machines, it dates back to ancient Rome, mainly to distinguish them from hand tools. In modern Chinese, the term \" Mechanics \" refers to a general term for mechanisms and machines in English. The characteristics of a mechanism are as follows: A machine is a combination of artificial physical components. There is a definite relative motion between the various parts of the machine. In addition to having the characteristics of mechanisms, machines must also possess a third characteristic: the ability to replace human labor in order to perform useful mechanical work or convert mechanical energy. Therefore, a machine is a mechanism that can convert mechanical energy or carry out useful mechanical work. From the perspectives of structure and motion, there is no difference between mechanisms and machines; they are collectively referred to as machinery. The definitions of mechanisms and machines originate from mechanical engineering and represent the most fundamental concepts in modern mechanics. The modern Chinese term for \"machine\" derives from the Japanese word for the same concept. Japanese mechanical engineering defines a machine as an assembly of objects that remains largely unchanged even when forces are applied to its various parts. These objects must achieve mutual, single, and prescribed motion. Convert the applied energy into its most useful form, or into effective mechanical work. (Explanation): A general term for all machines and mechanisms that possess a definite motion system. Such as machine tools, tractors, etc ； Rigid ； Not flexible. 1. Common explanation: A machine is a simple device that can transfer energy or force from one place to another. It can change the shape and structure of objects to create new items. In our daily lives, there are countless different types of machines working for us. The everyday understanding of machinery is mechanical devices, that is, various machines and instruments. 2. Explanation of importance: From a mechanical engineering perspective, machinery holds a quite important fundamental role. Machinery is one of the five key elements for production and services in modern society (namely, people, capital, energy, materials, and machinery). When Marx talked about industrial society, he referred to it as an era in which machines are used for production, especially in large-scale industrial societies. Whether it’s the various physical devices we encounter in daily life, such as light bulbs, telephones, televisions, refrigerators, elevators, and so on, all of which contain mechanical elements or fall under the category of machinery in a broad sense; or from the perspective of production, various machine tools, automated equipment, airplanes, ships, the Shenzhou-5 and Shenzhou-6 spacecraft, etc., all rely on machinery. Not to mention chemical plants, power plants, etc. Therefore, it is no exaggeration to say that machinery is a foundation of modern society. If someone says that agriculture is also fundamental, that’s understandable. But in modern society, machinery, as the foundation of industry and engineering, can undoubtedly be regarded as a key pillar of society as well. Every modern industry and engineering field relies on the use of machinery, and even in people’s daily lives, various types of machinery are being used more and more often, such as cars, bicycles, clocks, cameras, washing machines, refrigerators, air conditioners, vacuum cleaners, and so on. 3. English explanation: machine, machine tool, mechanical CAD/CAM/CAE/CAPP/CIMS. 4. Related terms: machinery industry, machine, mechanism, mechanical manufacturing and automation, master machine tool, optimal design, modern methods of mechanical design, mechanical design, mechanism design, finite element analysis, reverse engineering. 5. Mechanical Design Manual, Chinese Encyclopedia of Mechanical Design, Chinese Society of Mechanical Engineers, Journal of Mechanical Engineering, Huazhong University of Science and Technology. Machinery is one of the five key elements for production and service in modern society (namely, people, capital, energy, materials, and machinery). Every modern industry and engineering field relies on the use of machinery, and even in people’s daily lives, various types of machinery are being used more and more often, such as cars, bicycles, clocks, cameras, washing machines, refrigerators, air conditioners, vacuum cleaners, and so on. Mechanical engineering is an applied discipline that, based on the relevant natural sciences and technical sciences as its theoretical foundation and combined with the technical experience accumulated through practical production, studies and solves theoretical and practical problems in the development, design, manufacturing, installation, operation, and repair of various machines. The development of various engineering fields requires corresponding progress in mechanical engineering, as all of them need the machinery provided by mechanical engineering. The invention and improvement of certain machines lead to the emergence and development of new engineering technologies and new industries. For example, the successful manufacturing of large-scale power machinery contributed to the establishment of electric power systems ； The invention of the locomotive led to the rise of railway engineering and the railway industry ； The invention and advancement of internal combustion engines, gas turbines, rocket engines, etc., along with the successful development of aircraft and spacecraft, led to the rise of the aviation and aerospace industries ； The development of high-pressure equipment has led to the success of many new types of synthetic chemical engineering, and so on. Mechanical engineering gains its driving force from the increasing demands in various fields, and it also possesses the ability to improve and innovate through advancements in various disciplines and technologies. The scope of mechanical engineering: Mechanical engineering serves a wide and diverse range of fields; any sector that utilizes machinery, tools, as well as energy and materials in its production processes relies on the services of mechanical engineering. In general, modern mechanical engineering has five main areas of application: developing and providing machinery for energy conversion, developing and providing machinery for manufacturing various products, developing and providing machinery for carrying out various services, developing and providing machinery for use in household and personal life, and developing and providing various types of military weapons. Regardless of the field it serves, the tasks in mechanical engineering are essentially the same, mainly including: establishing and developing the theoretical foundations of mechanical engineering. For example, engineering mechanics and fluid mechanics that study force and motion ； Engineering materials science that studies the properties of metallic and non-metallic materials and their applications ； Thermodynamics studying the generation, conduction, and conversion of thermal energy ； The study of the principles of mechanics and the theory of mechanical parts, which focuses on the working principles, structure, design, and calculation of various mechanical elements with independent functions ； Metalworking and non-metalworking, such as the study of the forming and cutting of metals and non-metals, etc. Research, design, and develop new mechanical products, continuously improve existing ones, and produce a new generation of mechanical products to meet current and future needs. The production of mechanical products, including: the planning and implementation of production facilities ； Formulation of production plans and production scheduling ； Developing and implementing manufacturing processes ； Designing and manufacturing tools and molds ； Determine labor quotas and material quotas ； Organize processing, assembly, testing, and packaging for shipment ； Effectively control product quality. Operation and management of machinery manufacturing enterprises. Machinery is generally a complex product assembled from many precision parts, each with its own unique forming and processing procedures. Production batches can be single units or small batches, as well as medium and large batches, up to mass production. Sales targets include all industries as well as individuals and families. Moreover, sales volume can experience significant fluctuations due to socioeconomic conditions. Therefore, the management and operation of machinery manufacturing enterprises are particularly complex, and research on production management, planning, and operation in such enterprises also originated primarily in the machinery industry. Applications of mechanical products. This includes the selection, ordering, acceptance, installation, adjustment, operation, maintenance, repair, and renovation of machinery and complete mechanical equipment used in various industries, in order to ensure the reliability and cost-effectiveness of these mechanical products over their long-term use. Study the environmental pollution and excessive consumption of natural resources generated during the manufacturing process of mechanical products, as well as in their use, and the measures to address them. This is a particularly important task in modern mechanical engineering, and its importance is growing day by day. Classification of mechanical engineering: There are a wide variety of machinery, which can be divided into different categories based on various criteria. For example, they can be classified by function into power machinery, material handling machinery, crushing machinery, etc ； Based on the industry sector, they can be classified into agricultural machinery, mining machinery, textile machinery, etc ； Based on their working principle, they can be classified into thermomechanical machines, fluid machinery, biomimetic machines, etc. Furthermore, machinery goes through several stages with different natures of work during its research, development, design, manufacturing, and operation. According to these different stages, mechanical engineering can be further divided into several interrelated and complementary subfields, such as mechanical research, mechanical design, mechanical manufacturing, and the operation and maintenance of machinery. These various sub-disciplinary systems, categorized according to different aspects, intersect and overlap with one another, enabling mechanical engineering to be divided into hundreds of sub-disciplines. For example, power machinery classified by function has complex intersections and overlaps with thermal machinery, fluid machinery, turbine machinery, reciprocating machinery, steam power machinery, nuclear power plants, internal combustion engines, and gas turbines classified by working principle; as well as with central power station equipment, industrial power plants, railway locomotives, marine engineering, automotive engineering, etc., classified by industry. Marine steam turbines are power machines; they are also thermal machines, fluid machinery, and turbine machinery. They belong to ship propulsion systems and steam power systems, and may also be part of nuclear power systems, among others. Analyzing this complex relationship and studying the most rational subfields of mechanical engineering holds certain intellectual value, but it does not have much practical significance. The development history of mechanical engineering: The hallmark of humanity becoming “modern humans” was the creation of tools. The various stone axes and hammers from the Stone Age, along with the simple and rough wooden and leather tools, were precursors to the machinery that emerged later. It was a long process that evolved from manufacturing simple tools to producing modern machines composed of multiple parts and components. Thousands of years ago, humans already created mortars and mills for threshing and grinding grains, buckets and pulleys for lifting water, vehicles with wheels, boats for sailing on rivers, as well as oars, paddles, and rudders. The power used has evolved from human physical strength to the utilization of animal power, water power, and wind power. The materials used have evolved from natural stones, wood, earth, and leather to synthetic materials. The earliest man-made material was ceramics, and the potter’s wheel used for making ceramic vessels was already a complete machine with three components: power, transmission, and mechanism. The development of blowers used to stoke the fires played an important role as humanity moved from the Stone Age to the Bronze Age, and then on to the Iron Age. A sufficiently powerful blower is needed to enable the metallurgical furnace to reach a high enough temperature in order to extract metal from the ore. In China, blowers for smelting were already in use between 1000 and 900 BC, and they gradually evolved from manual blowing to blowing powered by animals and water. Before the 15th–16th centuries, mechanical engineering developed slowly. However, through millennia of practice, considerable experience and technical knowledge have been accumulated in the field of mechanical development, which became an important source of potential for the subsequent growth of mechanical engineering. After the 17th century, capitalism emerged in England, France, and other Western European countries, and commodity production began to become the central issue of society. In the late 18th century, the use of steam engines spread from the mining industry to sectors such as textiles, flour production, and metallurgy. The main material used for making machinery gradually shifted from wood to metal, which is stronger but more difficult to work with manually. The machinery manufacturing industry began to take shape and became an important sector over the course of several decades. Through continuous expansion of its practices, mechanical engineering has evolved from a fragmented craft that relied primarily on the individual intelligence and skills of craftsmen, into a theoretical, systematic, and independent engineering discipline. Mechanical engineering was the main technical factor that drove the Industrial Revolution in the 18th and 19th centuries, as well as capitalist large-scale mechanical production. Motivation is an important factor in developing production. In the late 17th century, with the improvement and development of various machines, and as the demand for coal and metal ores increased year by year, people realized that relying on human and animal power was not sufficient to take production to a new level. In Britain, industries such as textiles and milling increasingly located their factories by rivers, using water wheels to power machinery. But at that time, the groundwater in mines such as coal mines, tin mines, and copper mines could still only be pumped out and removed using a large amount of animal power. Driven by such production needs, Newcomen’s atmospheric steam engine appeared in the early 18th century to power mine drainage pumps. However, this type of steam engine has a high fuel consumption rate and is basically used only in coal mines. In 1765, Watt invented the steam engine with a separate condenser, which reduced fuel consumption. In 1781, Watt invented a steam engine that provided rotational power, thereby expanding the range of applications for steam engines. The invention and development of the steam engine enabled mechanical power to be used in mining and industrial production, as well as in railways and shipping. The steam engine was almost the only source of power in the 19th century, but it and its boilers, condensers, cooling water systems, etc., were large and bulky, making them inconvenient to use. At the end of the 19th century, power supply systems and electric motors began to develop and be widely adopted. At the beginning of the 20th century, electric motors had replaced steam engines in industrial production, becoming the primary power source for various working machines. Mechanization in production is inseparable from electrification, and electrification in turn exerts its effect on production through mechanization. Power stations initially used steam engines as their power source. In the early 20th century, steam turbines with high efficiency, high speed, and large power capacity emerged, as did turbines suitable for various water resources, which contributed to the rapid development of power supply systems. The internal combustion engine, invented in the late 19th century, underwent continuous improvements over the years, becoming a prime mover that is light and compact, efficient, easy to operate, and capable of starting at any time. It was first used to power land-based machinery that had no electricity supply, and later it was applied to cars, mobile machinery, and ships; by the mid-20th century it began to be used in railway locomotives. Under the competition from turbines and internal combustion engines, the steam engine is no longer an important power machine. The development of internal combustion engines, as well as the gas turbines and jet engines invented later, is one of the key technical factors that enabled the successful development of airplanes, spacecraft, and other such vehicles. Before the Industrial Revolution, most machinery was of wooden construction and made by carpenters by hand. Metals (mainly copper and iron) are used only to manufacture instruments, locks, clocks, pumps, and small parts for wooden machinery. Metal processing relies primarily on the meticulous work of craftsmen to achieve the desired precision. The widespread use of steam engine power systems, along with the development of large-scale machinery such as those used in mining, metallurgy, shipping, and railways, led to an increasing demand for metal parts that required shaping and cutting processes. These parts became larger and larger, and the precision expectations for them also increased. The metal materials used have evolved from copper and iron to steel being the primary material. Mechanical processing, which includes technologies and equipment such as forging, pressing, sheet metal working, welding, and heat treatment, as well as cutting processes along with machine tools, cutting tools, and measuring instruments, has developed rapidly, ensuring the supply of mechanical equipment needed for production in various industries. With the development of the social economy, there has been a surge in demand for mechanical products. The increase in production batches and advancements in precision machining technologies have led to the development of mass production methods, such as interchangeable part production, specialized division of labor and cooperation, assembly lines, and flow-line manufacturing processes. Simple interchangeable parts and specialized division of labor for collaborative production existed already in ancient times. In mechanical engineering, interchangeability was first demonstrated by Mozzoli in 1797 with the bolts and nuts produced using his newly invented thread turning machine. Around the same time, American engineer Whitney used the interchangeability production method to manufacture firearms, demonstrating the feasibility and advantages of interchangeability. This production method was gradually adopted in the United States, giving rise to what is known as the “American production method”. In the early 20th century, Ford invented the assembly line in automobile manufacturing. Mass production techniques, combined with the scientific management methods developed by Taylor at the end of the 19th century, enabled the production efficiency of cars and other mechanically manufactured goods produced in large quantities to reach levels that were unimaginable in the past. In the middle and later years of the 20th century, the main characteristics of machine processing were the continuous improvement in the speed and precision of machine tools, as well as a reduced reliance on manual skills ； Increase the level of mechanization and automation in forming, cutting, and assembly processes ； By utilizing CNC machines, machining centers, cell technology, etc., flexible manufacturing systems are developed to raise the production efficiency of small-to-medium batch sizes and multi-product production to levels close to those of mass production ； Research and improve the forming and machining technologies for new, difficult-to-machine metal and non-metal materials. Before the 18th century, mechanical craftsmen relied solely on experience, intuition, and skill to create machinery, with little connection to science. By the 18th and 19th centuries, driven by the emerging capitalist economy, those who possessed scientific knowledge began to pay attention to production, while the craftsmen who were directly involved in production started to learn scientific and cultural knowledge. The exchange and mutual inspiration between them yielded significant results. Throughout this process, a complete set of fundamental theories surrounding mechanical engineering gradually took shape. Power machinery was first combined with the advanced science of that time. Savery and Watt, the inventors of the steam engine, applied the theories of physicists Papin and Black ； Based on the practical applications of steam engines, physicists Carnot, Rankine, and Kelvin established a new science—thermodynamics. The theoretical foundation of the internal combustion engine was established by Frenchman Rochas in 1862 ； In 1876, Otto applied Losh’s theory to thoroughly improve the crude, bulky, noisy, and low-thermal-efficiency internal combustion engine he had originally created, thereby establishing the importance of internal combustion engines. Others such as steam turbines, gas turbines, and hydroturbines have been developed under the guidance of theory, while the theory itself has also been improved and refined through practice. As early as in the pre-Buddhist era, China employed complex gear systems in compass vehicles, as well as mechanisms such as cross-shaped frames that could maintain a horizontal position in incense burners. Ancient Greece already had records of cylindrical gears, bevel gears, and worm drives. However, theoretical explanations regarding the relationship between the instantaneous speed ratio of gear transmission and the tooth shape, as well as the selection of tooth profile curves, did not appear until after the 17th century. Hand cranks and pedal mechanisms were precursors to the crank-slider mechanism, with a long history in various ancient civilizations; however, the precise analysis and synthesis of the form, motion, and power of the crank-slider mechanism are achievements of modern mechanism theory. As a specialized discipline, mechanics was not included in the curriculum of higher engineering schools (the École des Arts et Métiers in Paris) until the early 19th century. Through theoretical research, it is possible to accurately analyze various mechanisms, including the motion of complex spatial linkage mechanisms, and thereby to develop new mechanisms as needed. The subject of work in mechanical engineering are dynamic machines, whose operating conditions can change significantly. Such changes are sometimes random and unpredictable ； The materials used in practical applications are not entirely uniform either, and may contain various defects ； There is a certain deviation in the machining precision, and so on. Compared to civil engineering, which deals with static structures, various problems in mechanical engineering are more difficult to solve precisely using theory. Therefore, early mechanical engineering relied only on simple theoretical concepts, combined with practical experience, to carry out work. Design calculations rely heavily on empirical formulas ； To ensure safety, a conservative approach is adopted, resulting in machinery that is bulky and large, costly, low in productivity, and highly energy-intensive. Since the 18th century, the continuous emergence of new theories and the development of mathematical methods have led to an increasing precision in design calculations. Entering the 20th century, various experimental stress analysis methods emerged, allowing people to measure the stresses in different parts of models and actual objects using experimental techniques. In the second half of the 20th century, the widespread use of the finite element method and electronic computers made it possible to analyze and calculate forces, moments, stresses, etc., for complex machinery and its components. For machinery or its components for which there is ample practical or experimental data available, statistical techniques can already be employed to carry out mechanical design scientifically, in accordance with the desired reliability level. Future prospects of mechanical engineering: Mechanical engineering aims to develop new mechanical products in order to increase production, boost labor productivity, and improve the economic efficiency of production. In the future, the development of new products will aim to reduce resource consumption, advance clean renewable energy, and manage, mitigate, and ultimately eliminate environmental pollution as its key economic objectives. Machines can perform tasks that humans can accomplish with their hands, eyes, feet, and ears – both those that can be done directly and those that cannot – and do so faster and better. Modern mechanical engineering creates increasingly sophisticated and complex machines and mechanical devices, turning many past fantasies into reality. Humans can now travel into the sky and universe, dive deep into the oceans, gaze across billions of light-years, and examine cells and molecules up close. The emerging science of computer hardware and software has enabled humanity to develop technological tools that enhance and partially replace the human brain – this is artificial intelligence. This new development has already shown tremendous impact, and in the years to come it will continue to create miracles beyond people’s imagination. The growth of human intelligence does not diminish the role of the hands; on the contrary, it requires them to perform more, more delicate, and more complex tasks, thereby further enhancing their functions. The practice of the hands, in turn, promotes the wisdom of the human brain. Throughout human evolution, as well as in the development of each individual, the brain and hands have evolved in tandem and in a mutually reinforcing manner. The relationship between artificial intelligence and mechanical engineering is similar to that between the brain and the hands, with the only difference being that the hardware for artificial intelligence also needs to be manufactured using mechanics. In the past, various machines relied on human operation and control, and their response speed and operational precision were limited by the slowly evolving human brain and nervous system; artificial intelligence will eliminate this limitation. The mutual promotion and parallel progress between computer science and mechanical engineering will enable mechanical engineering to embark on a new phase of development at a higher level. In the 19th century, the body of knowledge related to mechanical engineering was still quite limited; in European universities, it was generally combined with civil engineering as a single discipline known as civil engineering. It was only in the second half of the 19th century that it gradually became an independent discipline. Entering the 20th century, with the development of mechanical engineering technology and the increase in the total amount of knowledge, mechanical engineering began to split up, giving rise to specialized sub-disciplines one after another. This trend of decomposition reached its peak in the mid-20th century, around the time when World War II ended. Since the total volume of knowledge in mechanical engineering has expanded to an extent that no individual can master it entirely, a certain level of specialization is essential. However, excessive specialization leads to an over-segmentation of knowledge, a narrow perspective, and an inability to take an overall view of slightly larger-scale projects; it also narrows the scope of technical exchanges, hinders the emergence of new technologies and overall technological progress, and results in poor adaptability to changes in external conditions. Experts in specialized fields possess overly narrow knowledge and think in a highly specialized manner; this makes it difficult for them to work together effectively, and it also hinders their ability to continue learning and improving on their own. Therefore, starting from the mid-to-late 20th century, a comprehensive trend emerged again. More attention has been paid to fundamental theories, professional fields have been expanded, and overly specialized fields have been merged. The repeated cycle of integration – specialization – reintegration is a rational and inevitable process in the development of knowledge. Experts from different fields possess sophisticated specialized knowledge, as well as sufficient comprehensive knowledge to recognize and understand the issues in other disciplines and the overall picture of engineering projects; only then can they form a cohesive team capable of working together effectively. Comprehensiveness and specialization are multi-level. Within mechanical engineering, there is a conflict between comprehensiveness and specialization ； Comprehensive engineering also involves comprehensive and specialized issues. Within all of human knowledge, including social sciences, natural sciences, and engineering technologies, there are also higher-level, more macroscopic comprehensive and specialized issues. Last edited by Drifting in the north on 2009-1-6 14:42]