Single-circuit power steering in right steer, function

B46.20-0042-05

Power steering schematic of a circuit when turning the wheel to the right (steering box on the left side)

1a, 1b Stroke control valve

3 Primary shaft

4 Steering worm

5 Torsion Bar

6 Star valve

7 Pressure control valve

8 Steering box

9 Rotor

10 Power steering pump

11 Hydraulic oil reservoir

12 Working piston

13 Distribution cover- above

14 Distribution cover - below

A Cross star valve

a Return groove

B46.20-0043-04

Stroke control valve in gear position to the right (steering box on the left side)

1a, 1b Stroke control valve

12 Working piston

A Lower working chamber

B Upper working chamber

Operation

When turning the wheel to the right, the threaded working piston (12) of the recirculating ball system to the left (wheel to the left) is moved mechanically to the lower working chamber (A).

For hydraulically balancing the mechanical displacement of the working piston (12), the oil is pushed into the upper working chamber (B).

In the wheel rotation transmission to the main shaft (3) or vice versa, the torsion bar (5) of the steering housing (8) elastically deforms (torsion), so that there is relative movement between the rotor (9) and distribution caps (13, 14). This way, the rotor distribution edges (9) to move from the central (neutral) position in relation to the distribution edges of the distribution covers (13, 14).

When turning the wheel to the right (wheel to the left), the oil supply duct to the upper working chamber (B) opens according to the degree of the steering wheel rotation, and allows the oil flow to the upper chamber.

At the same time, the oil return duct of the upper working chamber (B) is reduced or closes according to the degree of rotation of the steering wheel generating the required pressure in the upper chamber.

The oil from the lower working chamber (A) is impelled by movement of the working piston (12) to the oil return duct of the lower working chamber and flows, through the oil return pipe, to the power steering reservoir (11).

The pressure generated in the upper working chamber (B) acting on the working piston (12) provides the hydraulic steering assistance. With the piston movement to the lower working chamber (A), (turning to the right - wheel to the left), the stroke control valve (1a) is actuated when it touches the bottom stop and thus allows oil to flow from the upper working chamber (B) to the lower working chamber (A) and the oil return tube through star valve (6). The oil pressure on the upper working chamber (B) decreases proportionally.