Patent · US Active

Plastic spring and method and apparatus for making the same

US8939438B2 · kind B2 · utility

11Cited by
16References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 8, 2010
Grant dateJan 27, 2015
Priority date
Expiry dateAug 31, 2032

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29L2031/7742
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

This invention provides a helical spring formed of plastic material, comprising a pair of end coils situated at respective ends of said helical spring; at least one full pitch active coil between said pair of end coils; a pair of transition coils, each transition coil interconnecting an end of a respective end coil to an end of a respective proximate full pitch active coil, and having a varying pitch.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.