Patent · US Expired

Retractable running-board, especially for a railway car door

US4188889A · kind A · utility

91Cited by
5References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 8, 1978
Grant dateFeb 19, 1980
Priority date
Expiry dateMay 8, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB61D23/025
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A movable step displaceable by means of an operating mechanism between a withdrawn position and a service position has an extension in the form of two transverse arms associated with two pairs of link-arms which are pivotally mounted on four shafts having horizontal and parallel axes. Two shafts are stationarily fixed on the floor of the railway car, the second shaft being set back from the first with respect to the car wall. The other two shafts are movable and attached respectively to the transverse arms near the point of connection of these arms to the step, and to the transverse arms at the ends which are pivotally attached to the rear link-arms. Stable immobilization of the step is achieved in the service position as a result of abutting application of the articulations of the transverse arms and of the rear link-arms against a stop.

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