Machine element

{{Short description|Elementary components used in the structure, controls, or mechanisms of a machine}} thumb|400px|NSK Support Roller cut (cropped)

'''Machine element''' or '''hardware''' refers to an elementary component of a machine. These elements consist of three basic types: # ''structural components'' such as frame members, bearings, axles, splines, fasteners, seals, and lubricants, # ''mechanisms'' that control movement in various ways such as gear trains, belt or chain drives, linkages, cam and follower systems, including brakes and clutches, and # ''control components'' such as buttons, switches, indicators, sensors, actuators and computer controllers.<ref>Robert L. Norton, '''Machine Design,''' (4th Edition), Prentice-Hall, 2010</ref>

While generally not considered to be a machine element, the shape, texture and color of covers are an important part of a machine that provide a styling and operational interface between the mechanical components of a machine and its users.

''Machine elements'' are basic mechanical parts and features used as the building blocks of most machines.<ref>{{Citation | last1 = Matthews | first1 = Clifford | author2-link = American Society of Mechanical Engineers | last2 = American Society of Mechanical Engineers | title = ASME engineer's data book | page = 249 | publisher = ASME Press | year = 2005 | edition = 2nd | url = https://books.google.com/books?id=dPS2KU0gj-8C&pg=PA249 | isbn = 978-0-7918-0229-8 | postscript =.}}</ref> Most are standardized to common sizes, but customs are also common for specialized applications.<ref name="bhandari">{{Citation | last = Bhandari | first = V. B. | title = Design of machine elements | page = 10 | publisher = Tata McGraw-Hill | year = 2007 | edition = 2nd | url = https://books.google.com/books?id=d-eNe-VRc1oC&pg=PA10 | isbn = 978-0-07-061141-2 | postscript =.}}</ref>

Machine elements may be features of a part (such as screw threads or integral plain bearings) or they may be discrete parts in and of themselves such as wheels, axles, pulleys, rolling-element bearings, or gears. All of the simple machines may be described as machine elements, and many machine elements incorporate concepts of one or more simple machines. For example, a leadscrew incorporates a screw thread, which is an inclined plane wrapped around a cylinder.

Modern kinematics supplanted the theory of simple machines throughout the 19th century with the creation of kinematic chain theory, which mathematically models machine elements as parts of a system of links and joints with constrained relative motion.

Many mechanical design, invention, and engineering tasks involve a knowledge of various machine elements and an intelligent and creative combining of these elements into a component or assembly that serves an application.

==Structural elements== # Beams, # Struts, # Bearings, # Fasteners # Keys, # Splines, # Cotter pin, # Seals # Machine guardings

==Mechanical elements== # Engine, # Electric motor, # Actuator, # Shafts, # Couplings # Belt, # Chain, # Cable drives, # Gear train, # Clutch, # Brake, # Flywheel, # Cam, # follower systems, # Linkage, # Simple machine

==Types== {{Colbegin|colwidth=}} *Shafts<ref name="klebanov">{{Citation | last1 = Klebanov | first1 = Boris M. | last2 = Barlam | first2 = David | last3 = Nystrom | first3 = Frederic E. | title = Machine elements: life and design | publisher = CRC Press | year = 2008 | url = https://books.google.com/books?id=B0GXuJswHfMC&pg=PP1 | isbn = 978-0-8493-9563-5 | postscript =.}}</ref> *Coupling<ref name="klebanov"/> **Key<ref name="bhandari"/> **Spline<ref name="bhandari"/> *Bearing<ref name="bhandari"/> **Roller bearing **Plain bearing **Thrust bearing **Ball bearing **Linear bearing **Pillow block *Gears<ref name="klebanov"/> **Spur gear **Helical gear **Worm gear **Herringbone gear *Fastener<ref name="niemann">Niemann, Gustav; Hirt, Manfred: ''Maschinenelemente'' Springer, Berlin 1975, 1983. {{ISBN|0-387-06809-0}}.</ref> **Screw<ref name="bhandari"/> ***Screw thread **Nut<ref name="bhandari"/> **Clevis fastener **Retaining ring ***Circlip ***E-ring **Split pin cotter pin) **Linchpin **R-clip **Rivet<ref name="bhandari"/> **Tapered pin **O-ring *Belt<ref name="bhandari"/> **Pulleys *Clutch<ref name="sharma">{{Citation | last1 = Sharma | first1 = C. S. | last2 = Purohit | first2 = Kamlesh | title = Design of machine elements | page = vii–ix | publisher = PHI Learning | year = 2004 | url = https://books.google.com/books?id=ZlnYpOtRhNEC&pg=PR7 | isbn = 978-81-203-1955-4 | postscript =.}}</ref> *Brake<ref name="sharma"/> *Chain<ref name="bhandari"/> **Sprocket *Wire rope<ref name="bhandari"/> *Power screw {{colend}}

==References== {{Reflist}}

==External links== *{{Commons category-inline|Machine elements}}

Category:Household hardware Category:Machines Category:Mechanisms (engineering) Category:Mechanical engineering