Title:
PIPE LAYER
Document Type and Number:
WIPO Patent Application WO/2014/188491
Kind Code:
A1
Abstract:
When a winch control valve is in a closed state, a pilot pressure control unit supplies hydraulic oil to the pilot port of a warm-up control valve so that the warm-up control valve is in an open state. When the winch control valve is in an open state, the pilot pressure control unit drains the hydraulic oil from the pilot port of the warm-up control valve so that the warm-up control valve is in a closed state. The length of the stroke of the spool of the warm-up control valve measured from the closing-side end of the stroke of the spool when the meter-out opening of the warm-up control valve is totally closed is greater than the length of the stroke of the spool of the winch control valve measured from the closing-side end of the stroke of the spool when the meter-in opening of the winch control valve is totally closed.
Inventors:
UEMURA TAKUYA (JP)
TAKEUCHI YASUHIKO (JP)
TAKEUCHI YASUHIKO (JP)
Application Number:
PCT/JP2013/063957
Publication Date:
November 27, 2014
Filing Date:
May 20, 2013
Export Citation:
Assignee:
KOMATSU MFG CO LTD (JP)
International Classes:
F16L1/024; F15B21/0427
Domestic Patent References:
| WO2012086695A1 | 2012-06-28 |
Foreign References:
| JPH11108015A | 1999-04-20 | |||
| JP2000074011A | 2000-03-07 | |||
| JPH10274212A | 1998-10-13 | |||
| JP2003239907A | 2003-08-27 |
Attorney, Agent or Firm:
Shinjyu Global IP (JP)
fresh green -- a global IP patent business corporation (JP)
fresh green -- a global IP patent business corporation (JP)
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