Plastic torsion spring

Could anyone give me any links to images/sites/existing products that show how a lid can pop/spring open about a pivot just using the plastic parts themselves and not a metal torsion spring?

Any help would be much appreciated.

Thanks.

Reply to
will_usher
Loading thread data ...

Sggest you head on over to DuPont's Design & Processing page

formatting link
and that you download document #7 "General Design Principles ... Module I"

formatting link
In chapter 6, pages 36-37, you find lost of info on designing springs on Homo-POM.

This ought to get you started ...

will snipped-for-privacy@yahoo.co.uk wrote:

Reply to
Rolf Wissmann

Take a look at a plastic and aluminium letter plate in your local diy shop, for example Homebase or Wickes. I have one for my front door which consists of a plastic moulded frame

- may be ABS - and an aluminium plate. The plate is retained shut by two torsion springs/pivot rods. These are around 1.5 ~ 2 mm diameter and about 50 mm long. They are injection moulded. One end has a 10 mm long lug which locates in a slot in the letter plate and the other end has a d-shape which is an interference fit in a d-shaped hole in the plastic frame. It worked very well - that is until my postie tried to deliver an overlarge item and busted it! I regret I don't know what the material of the torsion rod is. It is not a polyolefin, but other than that I cannot say. I suspect possibly nylon or acetal. Regards, Bill

Reply to
bill.king

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.