Patent · US Expired

Extendible crane boom

US5678708A · kind A · utility

6Cited by
5References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1995
Grant dateOct 21, 1997
Priority date
Expiry dateOct 24, 2015

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB66C23/705
  • WIPO fieldHandling
  • WIPO sectorMechanical engineering

Abstract

An extendible crane boom comprises, in addition to a tubular base boom section (1), a plurality of boom sections (2, 3, 4, 5) telescopically within the base boom section and each composed of a tube and a holder (8, 8', 8", 8"') mounted at an outer end thereof for connecting the tube to a double-acting hydraulic cylinder (9, 9', 9", 9"') with a view to displacing each boom section out of and into an immediately preceding boom section so as to lengthen and shorten, respectively, the crane boom in its entirety. The third and fourth hydraulic cylinders (9", 9"') are located in a first plane which is parallel to the longitudinal extent of the boom and located inwardly of a second plane, in which the first and second hydraulic cylinders (9, 9') are located. This minimizes the overall height of the outermost telescopic boom sections (4, 5), counted as the center distance between the telescopic tube concerned and the associated hydraulic cylinder.

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