Abstract There is provided a boom extending and retracting apparatus that can improve the convenience of the telescopic 5 boom while reducing the burden on the operator. The boom extending and retracting apparatus of the crane chooses the mode of the fluid circuit between the normal fluid circuit and the differential fluid circuit to slide a plurality of boom members by one telescopic cylinder. After the operating lever is turned 10 to an extension side and the controller starts extending the telescopic boom using the differential fluid circuit, when the operating lever is turned to the extension side again via the neutral position, the controller chooses the normal fluid circuit to extend the telescopic boom using the normal fluid 15 circuit. 31 34 /3 12 14 FRONT END BACK END 56 2 - 59 57 62 4-41 .-- __ 42 53 -44 45 42 58 36 2(2 41 7±3 23 7825(22) OPERATING PART 93 15 rP1 CONTROL PART o0 DEFAULT DATA ,98 DETECTION INTERRUPTION DISPLAY 92' PART FLAG
BOOM EXTENDING AND RETRACTING APPARATUS OF A CRANE
2019-01-31
Patent
Electronic Resource
English
IPC: | B66C Krane , CRANES |