Patent · US Expired

Safety belt retractors

US4215830A · kind A · utility

12Cited by
4References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 13, 1979
Grant dateAug 5, 1980
Priority date
Expiry dateJun 13, 1999

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60R2022/4426
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A safety belt retractor of a type including a pair of springs and a spring lock out mechanism enabling only one of the springs to operate when the belt is worn, in order to reduce belt tension, and to enable both of the springs to operate when the belt is released, to ensure reliable belt retraction. The retractor includes a sun and planet gear assembly including a gear ring, a planet gear and a sun gear. A shaft which rotates when the safety belt is retracted is coupled to a main spring by the sun and planet gear assembly. A stop limits orbital motion of the planet gear when the shaft is rotated, whereby the shaft is drivably coupled to the main spring through the gear assembly. A spring lock out mechanism secures the gearing against rotation, after the belt has been extracted, whereby the main springs stores its wound energy and its drive is disconnected from the shaft. An auxiliary spring, which is also coupled to the shaft, then applies a light bias to the belt. The spring lock out mechanism is released in response to orbital motion of the planet gear, when driven by the shaft, after releasing the belt which is retracted by the auxiliary spring.

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