What is Mechanism: Definition and 526 Discussions

In engineering, a mechanism is a device that transforms input forces and movement into a desired set of output forces and movement. Mechanisms generally consist of moving components which may include:

Gears and gear trains;
Belts and chain drives;
Cams and followers;
Linkages;
Friction devices, such as brakes or clutches;
Structural components such as a frame, fasteners, bearings, springs, or lubricants;
Various machine elements, such as splines, pins, or keys.The German scientist Franz Reuleaux defines machine as "a combination of resistant bodies so arranged that by their means the mechanical forces of nature can be compelled to do work accompanied by certain determinate motion". In this context, his use of machine is generally interpreted to mean mechanism.
The combination of force and movement defines power, and a mechanism manages power to achieve a desired set of forces and movement.
A mechanism is usually a piece of a larger process, known as a mechanical system or machine. Sometimes an entire machine may be referred to as a mechanism; examples are the steering mechanism in a car, or the winding mechanism of a wristwatch.
However, typically, a set of multiple mechanisms is called a machine.

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  1. entropy1

    I The mechanism of entangled particles

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  2. Uriel

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  3. C

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  4. O

    Can smaller bars be used in redesigning this lever mechanism?

    Hello everyone, I am currently doing an internship and I am working on a part that opens and closes using a pneumatic cylinder as you can see bellow Here is a force diagram I would like to redesign this in order to use a cylinder with a shorter stroke and perhaps a slightly bigger diameter...
  5. MeesterDave

    I in working out forces in a real mechanism

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  6. Daniel Barco

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  7. C

    Help with design for moving a box

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  8. T

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  9. W

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  10. R

    Mechanism for height adjustment of rotating body

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  11. Alistair McCheyne

    Slider Crank Mechanism Magnitude and Direction

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  12. T

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  13. K

    Design a automatic locking mechanism for two concentric cylinders

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  14. T

    Can a Swash Plate Mechanism be Adapted for Radial Displacement Along a Spoke?

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  15. C

    Higgs Mechanism and Lorentz transformation of currents

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  16. B

    Reaction mechanism for ketone and vinyl lithium

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  17. D

    Mechanism for extinction by scattering?

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  18. S

    Designing a Tilting Mechanism for Air Hose, Locking Methods and Resources

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  19. N

    Discovering the Mobility of the Pictured Mechanism: Analysis and Insights

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  20. P

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  21. M

    Velocity-Based Time Dilation: Teen's $400k Video Correct?

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  22. V

    Microwave tube mechanism of heating

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  23. S

    Crank Slider mechanism analysis

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  24. thegreengineer

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    Before starting I want to say that this topic is from a subject I'm taking called vector mechanics. The subtopic dealt is called kinematics of rigid bodies. Homework Statement The wheel rotates around an axis. This point of reference of the center of the wheel is labeled as "A". This wheel...
  25. A

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  26. Raymond Potvin

    B Diffraction of light, the mechanism

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  27. M

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  28. K

    Is the Higgs mechanism a gauge transformation or not?

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  29. whitsona

    Foucault Pendulum: How important is release mechanism?

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  30. A

    Mechanism to move things around

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  31. W

    Vertical alignment mechanism on eccentric shaft

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  32. Y

    Mechanics, degree of freedom question

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  33. L

    What is the definition of the degrees of freedom in a kinematic chain?

    As I know, when a link in a kinematic chain is fixed, the kinematic chain will become a mechanism. And, I only know the definition of the DOF of a mechanism. Is there the definition of the DOF of a kinematic chain ?
  34. stevebenson

    Help identifying this pivoting joint mechanism

    Hello all, I need help identifying the following pivoting joint, and also coming to an understanding of how this particular joint works and is designed... Thanks for your help!
  35. A

    Totally Hypothetical, probably incorrect, Shock Wave Generation Mechanism

    So I was sitting around pondering about forces, and I found myself thinking about shock-waves. Whether they're caused by supersonic travel, or explosions, the pressure at the front of the wave-bow shock pressure is a force. So I started thinking of a way to generate them without having to go...
  36. Richard Roberts

    RichRoberts44/9_00596_24_zpsjjn45ocm.jpg[/URL]Help with Sliding Plate Mechanism

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  37. S

    Offset crank slider mechanism connecting rod analysis

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  38. D

    Feasibility and Advantages of Variable Wing Area Concept in UAV/RC Aircraft

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  39. Glurth

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  40. E

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  41. graceless9

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  42. D

    Hip joint torque in walking mechanism

    Hi everyone, I am making a hexapod ( six legged walking mechanism ) which walking by keeping 3 alternate legs in air and other 3 on ground, pushing the body ahead, also known as tripod gait. The basic structure of model and one leg are shown in the pictures. I want to calculate the torque...
  43. G

    Ebola Virus Disease: Mechanism of infection

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  44. C

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  45. S

    Explaining Universe Expansion Through Gravity & 3D Geometry

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  46. P

    Arm blade mechanism for Cosplay

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  47. N

    Charge of the W bosons in the Higgs Mechanism

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  48. Y

    Angular Velocity and Acceleration for Elevator Mechanism

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  49. M

    Synthesis of a four bar linkage with a ternary couplar

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  50. Vinay080

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