BY PASS

INPUT

CIRCULAR VALVE

SHAFT

 

GROOVES

VALVE NUT

 

OIL IN

OIL OUT

ROTARY

 

VALVE

DELIVERY FROM

SUPPLY

ROTARY VALVE

 

OUTPUT

SPINDLE ASSEMBLY W/

ROTARY VALVE (BALL

SHAFT

SCREW ASSEMBLY)

 

PISTON

 

SEAL AND

OIL PASSAGE

 

GLIDE RINGS

DRAIN PLUG

 

 

 

FIGURE 2

 

bar results in the input shaft rotating slightly in advance of the ball screw. The six pairs of grooves that form the rotary control valve are displaced from their neutral flow position. As steering effort increases so does the amount of displacement. Depending on the direction steered, the groove displacement of the input shaft directs hydraulic oil through

the appropriate drilled passages in the ball screw to one side or the other of the piston. Hydraulic pressure acting upon the piston surface eliminates much of the piston’s resistance to movement. Spring force exerted by the torsion bar causes the ball screw to rotate as piston resistance is removed. As the ball screw rotates, the relative groove

BY PASS

INPUT SHAFT

 

VALVE

BEARING

 

OIL INLET

OIL OUTLET

 

CONNECTING POLE

CIRCULAR

GROOVES

 

LONGITUDINAL

 

GROOVES

MECHANICAL

TORSION BAR

MOVEMENT PARTS

 

MECHANICAL-

BALL SCREW

 

HYDRAULIC PARTS

 

PARTS WITH NO

 

MOVEMENT

 

 

 

FIGURE 3

 

4

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BENDIX SD-30-4250 manual Delivery from