BMW S58, Руководство пользователя

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S58�Engine
7.�Oil�Supply
46
Index Explanation
5 Sprocket
6 Control�line,�second-level�control�(emergency�operation)
7 Oil�pump�drive
8 Control�plunger
9 Piston�pressure�side�of�the�axially�movable�impeller
10 Oil�duct�into�the�engine�block�(unfiltered�oil)
12 Second�level�control�pressure
13 Oil�duct�outlet
14 Oil�return�from�piston�to�sump
15 Oil�duct�to�the�piston�pressure�side
Through�the�interaction�of�the�map�control�with�the�control�piston�(8),�the�delivery�rate�of�the�oil�can�be
influenced�via�the�axially�movable�impeller�(3)�by�means�of�the�Digital�Motor�Electronics�(DME).
7.3.3.�Second-level�control�(emergency�operation)
During�normal�operation�or�if�the�map�control�fails,�the�delivery�rate�is�determined�via�the�second�level
control.�The�second-level�control�pressure�(2)�acts�on�the�smaller,�rear�surface�of�the�control�piston�(8).
The�second�level�control�pressure�(2)�presses�against�the�control�piston�spring�and�thus�adjusts�the
control�piston�(8)�toward�minimum�delivery.�By�being�moved�towards�the�minimum�delivery�position,
the�control�piston�(8)�opens�the�oil�duct�to�the�forward�piston�pressure�side�(15).�The�filtered�oil�from
the�oil�duct�(12)�is�now�conveyed�to�the�front�piston�pressure�side�(9)�of�the�axially�movable�impeller
(3).�On�account�of�the�axial�shift�caused�by�the�oil�pressure,�the�planes�of�contact�of�the�external�gear
wheels�are�reduced�and�the�delivery�rate�of�the�filtered�oil�decreases.
7.4.�Map�control�valve
On�the�S58�engine,�the�data-map�control�valve�is�mounted�on�the�crankcase�and�connected�to�the�oil
pump�via�holes�drilled�in�the�crankcase.
The�map-controlled�control�valve�is�a�proportional�valve�which�can�control�the�oil�pressure�steplessly.