Скачать или смотреть What is a Knuckle Joint? | Keys | Types of Keys |

Welcome back MechanicaLEi, did you know that tie rods and tension links in bridge structure that help the bridge stand make use of knuckle joints? This makes us wonder, what is a knuckle joint?
Before we jump in check out the previous part of this series to learn about What a Lathe is?
First, let’s find out what a key is? a key is used to connect a rotating machine element to a shaft. It prevents relative rotation between the two parts and may also enable torque transmission. Parallel keys have a square or rectangular cross-section. Square cross-sections are used for smaller shafts and rectangular cross-sections are used when the wall thickness of the mating hub is constrained. Feather keys are similar to the parallel keys except that they are radiused on both ends and machined to tight tolerances. Woodruff keys are semicircular, fitting partly into a circular segment keyway with the remainder fitting into a longitudinal slot keyway in the mating part. Parallel, woodruff and feather keys are all types of sunk keys. Lastly, Saddle keys are the keys that are attached to the driving member and are used to transmit power to the driven members like couplings.
Now, A knuckle joint is used to connect two rods under tensile load. This joint permits angular misalignment of the rods and may take compressive load if it is guided. In this type of joint, one of the rods has an eye at the rod end and the other one is forked with eyes at both the legs. A pin called knuckle pin is inserted through the rod-end eye and fork-end eyes. It is secured by a collar and a split pin. Knuckle Joint can withstand large tensile loads and has good mechanical rigidity. It is easy to manufacture and setup. However, it cannot withstand large compressive loads and permits angular moment in only one plane. Hence, we first saw what different types of keys are and then went on to see what Knuckle Joint is?
In the next episode of MechanicaLEi find out what couplings are?


Attributions:

Doh De Oh by Kevin MacLeod is licensed under a Creative Commons Attribution licence (https://creativecommons.org/licenses/...)
Source: http://incompetech.com/music/royalty-...
Artist: http://incompetech.com/

Subtle Library by Fabian Measures (http://freemusicarchive.org/music/Fab...) is licensed under a Creative Commons Attribution licence ( https://creativecommons.org/licenses/...)
Source: http://freemusicarchive.org/music/Fab...

Image of Keys:
https://jackdunigan.com/theres-a-reas...