Engineering:Form-fit connection

From HandWiki
The lid over the teapot is a form-fit connection along the vertical downward direction and any horizontal linear direction. It is not along a rotational direction.

A form-fit, form-locking or form-closed connection is a type of mechanical connection between two parts (example: screw and screwdriver), wherein these parts due to their forms interlock and block each other along at least one defined linear or rotational direction.[1][2][3][4]

Form-fit connections are created by the interlocking of the connecting components. For example, the lid cannot slip sideways away from the pot because both interlock at the edge. On the other hand, a round lid can be rotated while sitting on the pot, because there is no form-fit against the rotation. Towards the bottom, the lid has a stop against the pot. This is a "half form-fit" because upwards it can be removed.

A form-fit acts via the geometric contact of two effective surfaces, and the effective forces are transmitted as normal forces to the effective surfaces of a driver part (surface pressure and Hertzian contact stress). Typically, some manufacturing-related tolerance occurs in the connection during form-fit.

In a form-fit connection, one connection partner blocks the movement of the other. Such "blocking" occurs in at least one direction. If a second pair of surfaces is arranged opposite, the opposite direction is also blocked.

Examples

References

  1. Engineersfield. "Form fit and frictional locking connections" (in en-GB). https://engineersfield.com/form-fit-frictional-locking-connections/. 
  2. Prof. Dr.-Ing. H. Gruss: Maschinenelemente - Formschlüssige Verbindungen, Fachbereich 6, Hochschule Anhalt. In: www.hs-anhalt.de. Retrieved December 2022.
  3. Send, Dietmar; Peter Riegger & Joachim Wokurka, "Packaging with a subsequently moulded form-fit connection", US patent 7665281, published 2010-02-23, assigned to CFS Germany GmbH
  4. Altenbach, Holm; Johlitz, Michael; Merkel, Markus; Öchsner, Andreas (2022-12-02) (in en). Lectures Notes on Advanced Structured Materials. Springer Nature. ISBN 978-3-031-11589-9. https://books.google.com/books?id=0HKfEAAAQBAJ&dq=%22form+fit+connection%22&pg=PA204. 

de:Verbindungstechnik#Formschluss