##  [Four-Bar Linkage](/index.php/four-bar-linkage) 

  ##  [Four-Bar Linkage](https://engineering.quantumdictionary.io/four-bar-linkage-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A planar closed kinematic chain consisting of four rigid links connected end-to-end by four revolute (pin) joints, with one link fixed to provide a reference; the assembly constrains relative motion to a single degree of freedom and transmits motion and force between an input link, an output link and an intervening coupler link.