Technical data

23
9
The holding function and piston retraction are
achieved by reducing the oil feed on the side
with the largest piston surface area by partly
actuating the proportional valve. The reduced
oil feed decreases the oil pressure, thus
initiating a change in the forces exerted on the
adjustment pistons. The retraction movement
of the adjustment pistons is supported by the
camshafts as they push back the spline shafts
in the hydraulic units due to the helical gearing
in the VANOS gear mechanism.
VANOS gear mechanism
The VANOS gear mechanism connects the
crankshaft with the intake camshafts as well as
the exhaust camshafts. The gear mechanism
also permits "torsion" of the camshafts. The
gear mechanisms for the intake and exhaust
sides differ in terms of the exterior structure of
the gear and chain drive while the adjustment
mechanism on the inner side is identical.
The gear mechanism is driven by the drive
gearwheel that interacts with the helical
gearing on the inner sleeve. The threaded
connections for the gearing connects the
inner sleeve to the outer sleeve. With (wide)
helical gearing, the inner sleeve acts on the
bearing assembly for the drive gearwheel that
is firmly secured to the camshaft with the
central bolt.
11 - Adjustment piston extending
12 - Adjustment piston retracting
13 - VANOS gear mechanism
Index Explanation
1 Exhaust
2 Intake