DAF CF65, CF75, CF85 Series . Manual — part 960

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200423

2-5

General

STEERING BOX

ΧΦ65/75/85 series

7

3

Wheel deflection limiting
To reduce the system pressure at the maximum

wheel deflection, the piston is equipped with two

wheel deflection limiting valves (3) and (8).

The pins (2) and (9) of the wheel deflection

limiting valves touch their stops before the

maximum wheel deflection is reached. The pin

opens the valve (5) and both cylinder halves

become connected, thus decreasing the system

pressure.

The pin (2) of the wheel deflection limiting

valve (3) touches the cover (1), and the pin (9) of

the wheel deflection limiting valve (8) touches the

adjusting bolt (10).

The wheel deflection limiting valves are automa-

tically adjusted when a new steering box is fitted.

The wheel deflection limiting valves are fitted into

the piston using clamping bushes (4), thus

making it possible for the valves to slide within the

piston.

If a new steering box is fitted, the wheel deflection

limiting valves protrude far enough from the

piston so that they will touch the end stops (the

cover and the adjusting bolt) well before the

maximum wheel deflection is reached.

The first time the steering box is turned to its

maximum steering position (both to the left and to

the right) - with a front axle which is correctly

adjusted for maximum wheel deflection - the

2

9

3 4

5

5

6

7

1

8 4

10

S7 00 017

STEERING BOX

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General

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ΧΦ65/75/85 series

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wheel deflection limiting valves will be depressed

to the correct depth in the piston, resulting in a

correct valve adjustment.

If the wheel deflection is to be reduced (e.g.

because wider tyres have been fitted), the

adjustment of the wheel deflection limiting valves

must be reset. This is done as follows:

Place the steering box in the central position, and

screw adjusting bolt (10) further into the steering

box.

By moving the piston towards the adjusting

bolt (10), the wheel deflection limiting valve (8)

will touch the adjusting bolt (10), thus pushing the

valve (8) deeper into the piston. A distance pin (7)

is fitted between wheel deflection limiting

valves (3) and (8). If the valve (8) is pushed

deeper into the cylinder, the valve will touch the

pin (7), and the pin will subsequently push the

valve (3) partially out of the piston.

By moving the piston in the direction of the

cover (1) to the maximum wheel deflection, the

wheel deflection limiting valve (3) will touch the

cover and the valve will be pushed into the piston

to the correct depth. This completes correct

setting of the valve (3). During this action, the

wheel deflection limiting valve (8) is also pushed

partially out of the piston.

The correct setting of the wheel deflection limiting

valve (8) is finally restored using the adjusting

bolt (10).

1 2

4 5

6 7

8

9

11

3

15

10

12

13

14

16

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General

STEERING BOX

ΧΦ65/75/85 series

7

3

Mechanical linkage
If the hydraulic power steering is cut off, the

torque on the input shaft (2) is mechanically

transferred to the steering rod.

The input shaft (2) and the worm shaft (12) can

rotate in relation to each other. This rotation is

limited by an end stop.

While steering without the hydraulic power

steering, the steering force at the input shaft (2) is

transferred to the worm shaft (12) by the end

stop.

The ball curve (10) converts the rotating

movement of the worm shaft into the linear

movement of the piston (13). The teeth of the

piston (13) rotate the sector shaft (11) with the

pitman arm attached to it.

Gear backlash
Because the gearing of the sector shaft (11) and

the piston (13) are constantly engaged when

driving straight forward, slight wear may occur.

This wear can cause gear backlash. To eliminate

this gear backlash, the sector shaft can be

adjusted axially using an adjusting bolt. The

adjusting bolt pushes the bevelled teeth of the

sector shaft (11) deeper into the teeth of the

piston (13), thus eliminating any play.

The sector shaft gearing (11) is such that the

tooth engaging the piston teeth when the steering

box is in its central position is slightly longer than

the other teeth.

After the play in the central position of the

steering box has been corrected, the piston

should be prevented from jamming in other

positions. As a result play is perceptible outside

the central position.

STEERING BOX

2-8

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200423

General

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ΧΦ65/75/85 series

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