Global Patent Index - EP 0368811 A1

EP 0368811 A1 19900516 - A reset device for hydraulic load control systems.

Title (en)

A reset device for hydraulic load control systems.

Title (de)

Rückstellgerät für hydraulische Laststeuerungsanlagen.

Title (fr)

Dispositif de réinitialisation pour systèmes hydrauliques de contrÔle de la charge.

Publication

EP 0368811 A1 19900516 (EN)

Application

EP 89830308 A 19890704

Priority

  • IT 4016588 A 19881109
  • IT 4016688 A 19881109

Abstract (en)

The device is intended in particular for cranes provided with hydraulic load control systems piloted by a pressure signal proportional to the overturning moment generated by the load, which produce control signals that block any movement of the crane likely to increase the load; use is made of a three-position bleed-off valve (12) which, in a non-stable position assumed momentarily as the spool shifts back and forth between two stable positions, brings about a reduction in the pilot pressure directed into the control system (10) so as to avoid lock-up of the crane that can occur in certain maximum load conditions. A valve (12) of this type also achieves a significant reduction of the hysteresis that traditionally delays the return of such systems (10) to the passive state.

IPC 1-7

B66C 23/90

IPC 8 full level

B66C 23/90 (2006.01)

CPC (source: EP)

B66C 23/90 (2013.01)

Citation (search report)

[A] GB 2078197 A 19820106 - HIAB FOCO AB

Designated contracting state (EPC)

AT DE ES FR GB IT SE

DOCDB simple family (publication)

EP 0368811 A1 19900516

DOCDB simple family (application)

EP 89830308 A 19890704