| 摘要 |
<p>PURPOSE: To maintain a desired load outlet pressure by energizing a movable valve member by a feedback means in the direction the movable valve member is reversely moved and also in the direction the operating fluid inlet is communicated with a selected load outlet. CONSTITUTION: A proportional pressure control valve assembly 10 applies the hydraulic pressure regulated by a load level controller 100 to a control piston 38 or 40 of an operating fluid outlet part 14 by the on/off action of the solenoid operators 90, 92 of a pilot operator part 12, so that a spool 42 is moved right or left to operate a cylinder 16. In this case, the hydraulic pressure introduced into the fluid chambers 20, 22 of the cylinder 16 is fed back onto both ends of the spool 42 via feedback passages 72, 74, so that the spool 42 is energized in the reverse direction to the energizing direction of the control pistons 38, 40, and in the direction the operating fluid inlet 60 is communicated with the load outlet 64 or 66, to maintain the load level applied to the cylinder 16 to a prescribed pressure. Thus, the desired load outlet pressure can be accurately adjusted and maintained.</p> |
