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Description
In the position shown, fluid under pressure, admitted into the directional valve, is delivered to the power cylinder. A part of the fluid is admitted into the housing of pilot valve spool 2 and from there, through one of the flow-control valves 4, to the right end of spool 3. Fluid from the exhaust end of the cylinder is drained through the valve to the tank. Braking of the machine tool table, linked to the piston of the power cylinder, is accomplished by cones a of spool 3 which throttle the fluid being drained from the cylinder. The velocity of the spool and, consequently, the braking conditions are varied by adjusting flow-control valves 4. At a definite setting of the flow-control valve, the velocity of spool 3 and the braking time are constant for all table travel speeds. When lever 1 is turned about fixed axis A, pilot spool 2 is shifted to the right. At this, a part of the fluid under pressure is admitted to the left end of spool 3, shifting it to the right as well. This delivers fluid under pressure to the other end of the power cylinder. The exhaust end of this cylinder is connected to the tank. $3918$LHP,FC$
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