EP 1600419 A4 20061227 - HYDRAULIC CONTROL DEVICE OF HYDRAULIC WORKING MACHINE

Title (en)

HYDRAULIC CONTROL DEVICE OF HYDRAULIC WORKING MACHINE

Title (de)

HYDRAULISCHE STEUERVORRICHTUNG EINER HYDRAULISCHEN ARBEITSMASCHINE

Title (fr)

DISPOSITIF DE COMMANDE HYDRAULIQUE D'UNE MACHINE DE TRAVAIL HYDRAULIQUE

Publication

EP 1600419 A4 20061227 (EN)

Application

EP 04715501 A 20040227

Priority

JP 2004002380 W 20040227
JP 2003051569 A 20030227

Abstract (en)

[origin: EP1600419A1] Provided are an lift cylinder 7 for causing a free end of a boom in a raising/lowering direction, an attachment pivotallymountedona free end portion of the boom, a tilt cylinder 8 for causing the attachment to turn in a raising/lowering direction relative to the boom, and a level cylinder 9 extendable/retractable in an interlocked relation with an up/down motion of the boom such that responsive to a change in the up/down angle of the boom, an angle of the attachment in a raising/lowering direction is maintained at a preset angle. When an operating pressure for the lift cylinder 7 becomes higher than a preset pressure during a boom raising operation, a line 35 on a side of a bottom chamber of the lift cylinder 7 and a line 33 on a side of a bottom chamber of the level cylinder 9 are brought into communication with each other. This communication is effected by a line 37, which is arranged between the lines 35 and 33, and a first and second selector valves 21,21 which changes over a circuit of this line 37. <IMAGE>

IPC 8 full level

B66F 9/22 (2006.01); B66F 9/065 (2006.01); E02F 3/43 (2006.01)

CPC (source: EP KR)

B66F 9/0655 (2013.01 - EP); B66F 9/22 (2013.01 - EP KR); E02F 3/433 (2013.01 - EP)

Citation (search report)

[A] EP 1195470 A1 20020410 - NEW HOLLAND ITALIA SPA [IT]
[A] DE 3545185 C1 19870723 - KRUPP GMBH
[A] DE 4331777 A1 19950330 - SCHAEFF KARL GMBH & CO [DE]
[A] FR 2731729 A1 19960920 - SOC ET ET D INNOVATION DANS LE [FR]
See references of WO 2004076334A1

Designated contracting state (EPC)

DE FR GB IT NL SE

DOCDB simple family (publication)

EP 1600419 A1 20051130; EP 1600419 A4 20061227; CN 1753831 A 20060329; JP WO2004076334 A1 20060601; KR 20050101351 A 20051021; WO 2004076334 A1 20040910

DOCDB simple family (application)

EP 04715501 A 20040227; CN 200480005323 A 20040227; JP 2004002380 W 20040227; JP 2005502952 A 20040227; KR 20057015504 A 20050822