| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydraulic controller capable of being bled of air and preventing a working fluid in a reflux-flow passage from reversely flowing to a pilot chamber. SOLUTION: There is provided a hydraulic controller equipped with a valve housing 1, a spool hole 2 formed in the valve housing 1, a spool 3 built in the spool hole 2 in a freely slidable manner, pilot chambers 5 to which an end of the spool 3 is adjacent, and a reflux-flow hole 17 which neighbors upon the pilot chambers 5 and is made to communicate with the spool hole 2 in the vicinity of both ends of the valve housing. In the hydraulic controller, a communicating spiral groove 21 is formed in an outer circumference of the end of the spool 3 and when the spool 3 is at a neutral position, the pilot chamber 5 and the reflux-flow hole 17 are cut off and pilot pressure is introduced to any of the pilot chambers 5. Then, when the spool 3 has moved a preset amount of distance, the pilot chamber 5 and the reflux-flow hole 17 communicate with each other via the spiral communicating groove 21. COPYRIGHT: (C)2008,JPO&INPIT
|
