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