PREVOST X3-45 Multiplex, Руководство по обслуживанию

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Section 1
Introduction
Copyright 2002 Maintenance Manual MM-0204
Page 2 ArvinMeritor, Inc. Issued 08-02
Operation
The compressor is driven by the engine. The
compressor’s crankshaft turns continuously while
the engine is running. Compression of air is
controlled by the
governor and by the
compressor’s unloading mechanisms .
The governor maintains the brake system air
pressure at preset maximum and minimum levels.
The governor is mounted apart from the
compressor, either horizontally or vertically. The
governor port is located on the crankcase of the
compressor.
Figure 1.3 .
The unloader mechanisms control the air
compression cycle; an air compression cycle has
three phases:
1. Induction: Air flows from the engine to the
compressor, opening the inlet valves in the
cylinder head of the compressor.
2. Compression: Air pressure is increased,
causing the compressor’s discharge valves to
open.
3. Unloading: Air passes from the cylinders to
the inlet chambers of the cylinder head via a
port controlled by sliding leaf valves.
When system cut-in pressure is reached, air is
exhausted from the unloader ports.
4. After unloading, the unloader pistons return
the sliding leaf valves to the loaded position.
This seals the unloader ports and compression
resumes.
Figure 1.4 .
Maintenance Intervals
The Meritor WABCO System Saver 636 twin
cylinder air compressor receives inlet air, oil and
coolant from the engine, so it is important to
follow the engine manufacturer’s
recommendations and maintenance schedules
regarding fluid levels, air filter and recommended
change intervals.
Cylinder Head
Remove carbon deposits from the discharge cavity
and rust and scale from the cooling passages of
the cylinder head.
Clean carbon and dirt from the inlet and unloader
passages.
Figure 1.3
1 GOVERNOR PORT
4000265b
1
Figure 1.4
1 SLIDING LEAF VALVES
4000266c
1 1