Title:
HYDRAULIC DRIVE SYSTEM FOR CONSTRUCTION MACHINERY
Document Type and Number:
WIPO Patent Application WO/2016/092809
Kind Code:
A1
Abstract:
A hydraulic drive system for construction machinery, comprising: a variable-capacity pump having a changeable tilt angle; a pair of rotation supply lines that connect a rotation control valve and a swing motor; a pair of electromagnetic relief valves provided, facing mutually opposite directions, in a crosslinking path connecting the pair of rotation supply lines; and a control device that controls the pair of electromagnetic relief valves such that the relief pressure becomes a standard pressure at times other than during rotation deceleration, and such that, during rotation deceleration, the relief pressure of the electromagnetic relief valve that releases hydraulic oil from the discharge-side rotation supply line drops significantly from the standard pressure the greater the rotation signal output from a rotation operation valve. The rotation control valve is configured so as to move in accordance with the rotation signal, at times other than during rotation deceleration, and to return to the center position during rotation deceleration.
More Like This:
Inventors:
KONDO AKIHIRO
ITO MAKOTO
ITO MAKOTO
Application Number:
PCT/JP2015/006070
Publication Date:
June 16, 2016
Filing Date:
December 07, 2015
Export Citation:
Assignee:
KAWASAKI HEAVY IND LTD (JP)
International Classes:
F15B11/028; E02F9/22; F15B11/00
Foreign References:
| JP2014095394A | 2014-05-22 | |||
| JP2014025209A | 2014-02-06 |
Attorney, Agent or Firm:
PATENT CORPORATE BODY ARCO PATENT OFFICE (JP)
Patent business corporation Owner old patent firm (JP)
Patent business corporation Owner old patent firm (JP)
Download PDF:
Previous Patent: HYDRAULIC DRIVE SYSTEM FOR CONSTRUCTION MACHINERY
Next Patent: WAVELENGTH-VARIABLE LASER DEVICE
Next Patent: WAVELENGTH-VARIABLE LASER DEVICE