There is a component which I've seen most often in car seat headrests which acts as a ratchet. You can pull the headrest forward and it will lock at steps until you pull it too far, and it will reset all the way back.

It's sort of a ratchet mechanism which resets after a certain range of motion.

I don't know what it's called. I've tried "resetting ratchet", "resetting step lock", and many other queries.

Do you know the name of this component?

I tried asking in DIY and they sent me here (https://diy.stackexchange.com/questions/214833/what-is-the-name-of-the-resetting-ratchet-component-found-most-often-in-head-res)

  • So, what do you need to tepair? Which bit is broken - the name won’t change the repair.
    – Solar Mike
    Jan 25, 2021 at 17:31
  • I'm not repairing, but building something from scratch. I need this component for what I'm making.
    – Seph Reed
    Jan 25, 2021 at 17:42
  • Well, try 3 or 4 bar chain - mechanical terms...
    – Solar Mike
    Jan 25, 2021 at 17:44
  • Hmmm... I tried searching both of those and didn't find anything. Would you mind sharing a link?
    – Seph Reed
    Jan 25, 2021 at 19:11
  • 1
    How about a "positioning pawl with end release"
    – John Canon
    Jan 28, 2021 at 6:50

2 Answers 2


I have an Allsop Redmond Notebook Stand that uses a "positioning pawl with end release" at each pivot point. You can raise the tilt angle click-click 6 times. On the seventh click the mechanism releases and the stand lowers back to its bottom position.

A more complex version exists on the tab key mechanism of some typewriters. See patents.google.com/patent/US3441119A/en .


I've found them called "Headrest Hinge" on Amazon and Ebay.


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