Title:
CONTROL VALVE FOR INDUSTRIAL VEHICLE
Document Type and Number:
Japanese Patent JP3853336
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To solve a problem in general industrial vehicles wherein an unloading pressure is excessively increased when the number of valve blocks or a flow rate is increased though the unloading pressure in the general industrial vehicles is desirable if it is low.
SOLUTION: A plurality of spools 5 to 8 for actuators for bringing a pump port P and a tank port T into a communicated state at a neutral position are disposed in a bypass passage 4. A pilot passage 34 connected to the primary sides of pilot valves controlling the spools from the bypass passage 4 on the upstream side of the upstream-most spool 5 is formed and a tank passage 14 converging a return oil from actuators connected to the control ports of the spools 5 to 8 to the bypass passage 4 on the downstream side of the downstream-most spool 8 is formed. A primary pressure generating valve 37 generating the primary pressures of the pilot valves 26 to 33 for controlling the spools is installed in the bypass passage 4 on the downstream side of the spool 8 on the upstream side of a converging point between the tank passage 14 and the bypass passage 4. A pressure leading passage 38 leading a control pressure to the primary pressure generating valve 37 is connected to the pilot passage on the downstream side of the upstream-most spool.
Inventors:
Noboru Ito
Seiji Aoki
Seiji Aoki
Application Number:
JP2004225440A
Publication Date:
December 06, 2006
Filing Date:
August 02, 2004
Export Citation:
Assignee:
Kawasaki Precision Machinery Co., Ltd.
International Classes:
F15B11/00; B66F9/22
Domestic Patent References:
| JP2002068696A | ||||
| JP2003004002A | ||||
| JP11002202U |
Attorney, Agent or Firm:
Yoshihiro Tsunoda
Yasu Furukawa
Toshio Nishitani
Keiji width
Izumi Uchiyama
Yosuke Koreeda
Yasu Furukawa
Toshio Nishitani
Keiji width
Izumi Uchiyama
Yosuke Koreeda