Patent · US Expired

Earthworking machine of the loader type

US4376612A · kind A · utility

12Cited by
2References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 12, 1981
Grant dateMar 15, 1983
Priority date
Expiry dateMay 12, 2001

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE02F3/308
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

The invention relates to a hydraulic loader comprising a boom, a balance beam and a bucket for loading material, boom jacks and balance beam jacks being coupled between the frame and the boom and between the boom and the balance beam. A secondary jack is also coupled between the frame and the boom and comprises an active chamber, while a first conduit connects this active chamber to the extension chamber of the balance beam jack and a first cut-off valve is disposed in this first conduit, establishing, in its first position, communication of the two sections of the first conduit which are connected thereto, isolating, on the contrary, in its second position, these two sections. One application of the invention is the production of a powerful and efficient loader.

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