Title:
CRANE
Document Type and Number:
WIPO Patent Application WO/2017/175862
Kind Code:
A1
Abstract:
Provided is a crane that is capable of protecting a hydraulic cylinder by suppressing operation of the hydraulic cylinder when the hydraulic cylinder is in poor connection with a hydraulic circuit. A crane (1) provided with a derricking cylinder (15) configured as a detachable hydraulic cylinder is configured in such a manner that: a head side hydraulic sensor (32) and a rod side hydraulic sensor (33) are provided to the derricking cylinder (15); and when the hydraulic pressure Pr of a rod side oil chamber (15F) becomes equal to or higher than the hydraulic pressure Ph of a head side oil chamber (15E) before a prescribed time T elapses after power supply to the head side hydraulic sensor (32) and to the rod side hydraulic sensor (33) is started, and a derricking direct-acting switching valve (28) is switched, by a derricking operation tool (22B), to a state of supplying hydraulic oil to the head side oil chamber (15E), it is determined that the rod side oil chamber (15F) and the derricking direct-acting switching valve (28) are not coupled to each other via a one-side joint (16A).
Inventors:
OKAMOTO TOSHIHIKO (JP)
MAEDA YASUHIRO (JP)
KAWABUCHI NAOTO (JP)
MAEDA YASUHIRO (JP)
KAWABUCHI NAOTO (JP)
Application Number:
PCT/JP2017/014541
Publication Date:
October 12, 2017
Filing Date:
April 07, 2017
Export Citation:
Assignee:
TADANO LTD (JP)
International Classes:
B66C13/20; F15B11/028; F15B20/00
Foreign References:
| JPH08282978A | 1996-10-29 | |||
| JP2002005122A | 2002-01-09 | |||
| JP2013542386A | 2013-11-21 |
Other References:
See also references of EP 3441347A4
Attorney, Agent or Firm:
YANO INTERNATIONAL PATENT ATTORNEYS OFFICE, P.C. (JP)
Download PDF: