Patent · US Expired

Actuator for telescopic boom

US4217987A · kind A · utility

20Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 1, 1978
Grant dateAug 19, 1980
Priority date
Expiry dateDec 1, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB66C23/701
  • WIPO fieldHandling
  • WIPO sectorMechanical engineering

Abstract

A telescopic boom comprises a base section, an inner section telescopable within the base section, an outer section telescopable within the inner section, and an actuator mechanism located within the outer section and operable to telescopically move the inner and outer sections relative to each other and to the base section. The actuator mechanism comprises an extendable and retractable elongated hydraulic cylinder or ram in the boom and comprising two relatively movable ram components, such as a cylinder housing and piston rod. One of the ram components (the piston rod) is connected to the base section and the other of the ram components (the cylinder housing) is connected to the inner section. An elongated cable support member is rigidly connected to the base section and extends into the boom. Means are provided to slideably support the first end of the hydraulic ram on the outer section and to slideably support the first end of the cable support member on the ram. First and second pulleys are mounted on the cylinder housing near opposite ends thereof, and first and second cables are reeved around the first and second pulleys, respectively. Each cable has one end anchored to the …

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