Title:
CONSTRUCTION MACHINERY
Document Type and Number:
WIPO Patent Application WO/2018/012264
Kind Code:
A1
Abstract:
Provided is construction machinery that can detect in real time during work that an excess flow control valve is stuck open without decreasing the speed of work. The construction machinery is provided with: an excess flow control valve control unit that outputs a close command to an excess flow control valve when starting an operation for which a control input signal from an operation lever device is detected; a pump discharge control unit that outputs a discharge flow command to a regulator for an open circuit pump; an assist valve control unit that continues output of the previous close command to an assist valve; a stuck detection determination unit that compares a pressure signal and a preset threshold value, determines that the excess flow control valve is stuck open if the pressure signal is less than the threshold value, and determines that the excess flow control valve is normal if the pressure signal exceeds the threshold value; and a stop signal generation unit to which a stuck determination signal is input, and that outputs a control signal to keep the assist valve in a closed state to the assist valve control unit when the valve is stuck open and that outputs a control signal to open the assist valve to the assist valve control unit when the valve is normal.
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Inventors:
SAITOH TEPPEI (JP)
SHIMIZU JURI (JP)
HIRAKU KENJI (JP)
TAKAHASHI HIROMASA (JP)
SUGIKI SHOUHEI (JP)
SHIMIZU JURI (JP)
HIRAKU KENJI (JP)
TAKAHASHI HIROMASA (JP)
SUGIKI SHOUHEI (JP)
Application Number:
PCT/JP2017/023416
Publication Date:
January 18, 2018
Filing Date:
June 26, 2017
Export Citation:
Assignee:
HITACHI CONSTRUCTION MACH CO (JP)
International Classes:
F15B20/00; E02F9/22; E02F9/24; F15B11/02; F15B11/08
Foreign References:
| JP2015048899A | 2015-03-16 | |||
| JP2008291962A | 2008-12-04 | |||
| JP2009121649A | 2009-06-04 | |||
| JP2016035321A | 2016-03-17 |
Other References:
See also references of EP 3486502A4
Attorney, Agent or Firm:
KAICHI IP (JP)
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