摘要 |
A power regulation device for a hydraulic pump includes a slidable piston having a first end face with a first diameter and a second, opposite end face with a smaller diameter, the second end face being biased by operating fluid pressure from the hydraulic pump and the first end face being biased by an adjustable fluid pressure for controlling the operation of the hydraulic pump; a compression spring which biases the piston in a direction against that of the adjustable fluid pressure; a measuring spring, one end of which biases the piston in the same direction as the compression spring; a power valve having a control slider member which is biased in one direction by the other end of the measuring spring and by the operating fluid pressure from the pump and in the opposite direction by a compression spring, the control slider member including a transverse channel for supplying the adjustable fluid pressure to the first end face of the piston during idling and normal operations and for connecting the adjustable fluid pressure at the first end face to a pressureless drain when the operating fluid pressure of the pump exceeds a first predetermined level; and a pilot valve including a control slider member biased in one direction by a spring and in the opposite direction by a fluid pressure, the control slider member of the pilot valve including a transverse channel for connecting the adjustable fluid pressure at the first end face of the piston to a pressureless drain during no-load and idling states of the hydraulic pump.
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