Product Code Database
Mechanization (or mechanisation) is the process of changing from working largely or exclusively by hand or with animals to doing that work with machinery. In an early engineering text, a machine is defined as follows:
In every fields, mechanization includes the use of hand tools. In modern usage, such as in engineering or economics, mechanization implies more complex than hand tools and would not include simple devices such as an ungeared horse or donkey mill. Devices that cause speed changes or changes to or from reciprocating to rotary motion, using means such as , or line shaft and belts, drive shaft, cams and cranks, usually are considered machines. After electrification, when most small machinery was no longer hand powered, mechanization was synonymous with motorized machines.Jerome (1934) gives the industry classification of machine tools as being "other than hand power". Beginning with the 1900 U.S. census, power use was part of the definition of a FACTORY , distinguishing it from a workshop. Extension of mechanization of the production process is termed as automation and it is controlled by a Feedback system in which feedback is provided by the sensors. In an automated machine the work of different mechanisms is performed automatically., Mechanical Engineering Community, retrieved 2018-04-17.
were some of the most complex early mechanical devices. Clock makers were important developers of machine tools including gear and screw cutting machines, and were also involved in the mathematical development of gear designs. Clocks were some of the earliest mass-produced items, beginning around 1830.. Reprinted by McGraw-Hill, New York and London, 1926 (); and by Lindsay Publications, Inc., Bradley, Illinois, ().
Water-powered bellows for blast furnaces, used in China in ancient times, were in use in Europe by the 15th century. De re Metallica contains drawings related to bellows for blast furnaces including a fabrication drawing.
Improved gear designs decreased wear and increased efficiency. Mathematical gear designs were developed in the mid 17th century. French mathematician and engineer Girard Desargues designed and constructed the first mill with epicycloidal teeth ca. 1650. In the 18th century , another mathematical derived design, came into use. Involute gears are better for meshing gears of different sizes than epicycloidal. Gear cutting machines came into use in the 18th century.
Demand for metal parts used in textile machinery led to the invention of many in the late 1700s until the mid-1800s. After the early decades of the 19th century, iron increasingly replaced wood in gearing and shafts in textile machinery. In the 1840s self acting machine tools were developed. Machinery was developed to make nails ca. 1810. The Fourdrinier paper machine for continuous production of paper was patented in 1801, displacing the centuries-old hand method of making individual sheets of paper.
One of the first mechanical devices used in agriculture was the seed drill invented by Jethro Tull around 1700. The seed drill allowed more uniform spacing of seed and planting depth than hand methods, increasing yields and saving valuable seed. In 1817, the first bicycle was invented and used in Germany. Mechanized agriculture greatly increased in the late eighteenth and early nineteenth centuries with horse drawn and horse powered threshing machines. By the late nineteenth century steam power was applied to threshing and steam tractors appeared. Internal combustion began being used for tractors in the early twentieth century. Threshing and harvesting was originally done with attachments for tractors, but in the 1930s independently powered combine harvesters were in use.
In the mid to late 19th century, hydraulic and pneumatic devices were able to power various mechanical actions, such as positioning tools or work pieces. Pile drivers and steam hammers are examples for heavy work. In food processing, pneumatic or hydraulic devices could start and stop filling of cans or bottles on a conveyor. Power steering for automobiles uses hydraulic mechanisms, as does practically all earth moving equipment and other construction equipment and many attachments to tractors. Pneumatic (usually compressed air) power is widely used to operate industrial valves.
After 1900 factories were electrification, and electric motors and controls were used to perform more complicated mechanical operations. This resulted in mechanized processes to manufacture almost all goods.
In mining and excavation, power shovels replaced picks and shovels. Rock and ore crushing had been done for centuries by water-powered , but trip hammers have been replaced by modern ore and .
Bulk material handling systems and equipment are used for a variety of materials including coal, ores, grains, sand, gravel and wood products.
Construction equipment includes cranes, , , and an assortment of power tools.
Many of the early machines and machine tools were hand powered, but most changed over to water or steam power by the early 19th century.
Before electrification, mill and factory power was usually transmitted using a line shaft. Electrification allowed individual machines to each be powered by a separate motor in what is called unit drive. Unit drive allowed factories to be better arranged and allowed different machines to run at different speeds. Unit drive also allowed much higher speeds, which was especially important for machine tools.Bartelt, Terry. Industrial Automated Systems: Instrumentation and Motion Control. Cengage Learning, 2010.
A step beyond mechanization is automation. Early production machinery, such as the glass bottle blowing machine (ca. 1890s), required a lot of operator involvement. By the 1920s fully automatic machines, which required much less operator attention, were being used.
When we compare the costs of using an internal combustion engine to a worker to perform work, we notice that an engine can perform more work at a comparative cost. 1 liter of fossil fuel burnt with an IC engine equals about 50 hands of workers operating for 24 hours or 275 arms and legs for 24 hours. 1 liter of fuel yielding 100 arms for 24 hours, when efficiency is 40% which is neverHome documentary by Yann Arthus Bertrand too stating that 1 liter of fuel yields 100 arms for 24 hours; probably from same calculation
In addition, the combined work capability of a human is also much lower than that of a machine. An average human worker can provide work good for around 0,9 hp (2.3 MJ per hour) while a machine (depending on the type and size) can provide far greater amounts of work. For example, it takes more than one and a half hour of hard labour to deliver only one kWh – which a small engine could deliver in less than one hour while burning less than one litre of petroleum fuel. This implies that a gang of 20 to 40 men will require a financial compensation for their work at least equal to the required expended food calories (which is at least 4 to 20 times higher). In most situations, the worker will also want compensation for the lost time, which is easily 96 times greater per day. Even if we assume the real wage cost for the human labour to be at US $1.00/day, an energy cost is generated of about $4.00/kWh. Despite this being a low wage for hard labour, even in some of the countries with the lowest wages, it represents an energy cost that is significantly more expensive than even exotic power sources such as solar photovoltaic panels (and thus even more expensive when compared to wind energy harvesters or luminescent solar concentrators). Combined work capability of human vs machines
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