Patent · US Expired

Telescopic boom apparatus

US5515654A · kind A · utility

30Cited by
15References
3Claims
0Family size

Inventor

Key dates

Filing dateNov 2, 1994
Grant dateMay 14, 1996
Priority date
Expiry dateNov 2, 2014

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE02F3/306
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A telescopic boom including an elongated hollow outer boom, an elongated inner boom telescopically received within the outer boom, and guidance structure for guiding the inner boom for telescopic movement is provided. The guidance structure includes a plurality of guide rails attached to the interior corners of the outer boom, a first roller assembly attached to one end of the inner boom, and a second roller assembly attached to one end of the outer boom. The first roller assembly includes a plurality of wheels mounted on axles for engaging the guide rails. Each of the wheels includes an arcuate rail-engaging portion which presents a radius of curvature equal to the radius of curvature of the guide rails. The second roller assembly includes a pair of roller bars positioned on opposed sides of one end of the outer boom for guiding the inner boom during telescopic movement. Each of the roller bars extends transverse to the longitudinal axis of the outer boom and is rotatably mounted on an elongated shaft.

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