Patent · US Expired

Fiber-reinforced plastic springs with helical fiber wind

US5549370A · kind A · utility

23Cited by
23References
15Claims
0Family size

Inventor

Key dates

Filing dateNov 7, 1994
Grant dateAug 27, 1996
Priority date
Expiry dateNov 7, 2014

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16F1/3665
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

Fiber-reinforced composite springs having a unidirectional fiber wind. The present invention is a cylindrical torsion bar, or a helical tension or compression spring having a core that is either unreinforced or axial-fiber reinforced, and a continuous-fiber-reinforced composite cladding having most or all of its fibers helically arrayed around the core. The core may be solid or hollow. The sense of the helical winding is that which places the fibers in tension when the spring is used as intended. A fiber winding helix angle of approximately 55.degree. is used with a weak and unreinforced core, while larger or smaller helix angles are used only with a cores having sufficient stiffness to resist axial-normal stress. By carefully selecting the materials for the core and cladding, as well as utilizing a fiber winding helix angle appropriate to the application, significant advantages over prior art springs are realized in energy per-unit-volume, energy per-unit-weight, and spring velocity.

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