ReChain positive locking mechanism

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An energetic barrier against loosening of a connection.
There are many ways to do this both in basic principle and concrete geometry of design.

– Via cliplocks (may be energetically irreversible snapping or reversible silent opereatable)
– Via van der Waals force at nanoscale possibly simplifying designs (may be combined with commensurately interdigitating surfaces)

Concrete designs

Indexed nut locking mechanisms

How it works

The lock-ring gets pushed up by a spring onto the nut. (Red TPU rubber in pic.)
Thereby reliably preventing the nut from undesired turning and loosening.

The lock-ring is prevented from rotating by rotationally locking to the
(in pic obstructed) spacer below the nut which in turn locks to flat of the screw.

Alternatively the spacer could lock to the the base via a RC/HirthJoint interface.
This seems even better because it does not depend on a flat screw.
(small diamondoid nanoscale screws can't really have their sides cut off)

Indexed nut locking mechanism.

(wiki-TODO: add image of individual parts – add arrows / numbers / text to the pic)

(TODO: Things to improve from this first prototype: …)
– clearance need to be be given not only radially with a cycloid profile
– spring needs improvements: more clearance, more sturdy, make it twist instead of bulging
– earlier nuts where to weak but this one is too beefy – fatter screw or thinner nut?
– change the spacer to lock to base via a Hirth joint interface rather than locking to the screw

Usage

The idea is to avoid using the screw directly for tensioning to:
– avoid application of high torques to the structure
– avoid the necessity to either transmit high forces or complex big gearing mechanisms at an end-effector

{{wikitodo| add scan of paper sketch here …}

This hall work as follows:
– a second nut B in a tool/end-effector gets screwed onto the screw (pushing back the lock-ring)
– a nonlinear high leverage double hinge mechanism pushes screw B and lock-ring (or better base) apart
– …

For details see: ReChain force hydrant

Related

External links