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Angular velocity sensors of individual type mounted in the wheels of front and rear axles
operating with the toothed impulse ring which is pressed onto the hub 5 are used for continuous
read of the wheel speed. Received signal is transmitted to the control unit via cables. The gap
between the rotor and the sensor should not exceed 0.7 mm for the normal operation of the sensor.
I.1.3.1.4 Service brake adjustment upon replacement of brake shoes or brake lin-
ings.
Adjust the clearances between the shoe and the drum using the brake shoe pins only
while replacing the friction linings or the brake shoes.
Fix the brake shoe pins in the initial position of face-to-face marking. Insert the probe of
0.2 mm thick and 200 mm long into the gap in the brake drum between the drum and the shoe at
30 mm from the bottom of the shoe lining. By turning the pin 12 of the brake shoe (Fig. I.9)
slightly clamp the probe. Remove the probe by turning the drum and with the help of another
probe and the adjusting cam gear 8 set the clearance of 0.35 mm between the shoe and the drum at
a distance of 30 mm from the upper edge of the lining. Fix the shoe pin and check the clearances
between the shoe and the drum again.
Replace the linings when they are worn out to the rivet hand surface.
When the brake shoes are greasy rinse them with petrol.
If the brake drum is worn out and circular grooves are more than 2 mm deep, bore the
drum working surface and locate the outer rings of the hub bearings off. The runout of the drum
work surface should not exceed 0.25 mm, the drum diameter should not exceed 424.38 mm.
I.1.3.1.5 Combined (air-hydraulic) drive of service brakes (for truck with 6
х
6 wheel
arrangement).
The truck is equipped with a three-circuit air hydraulic brake drive with additional brak-
ing valve, with double-wire trailer drive and ABS.
The compressed air from compressor 22 goes to air preparation unit consisting of oil
separator 2, moisture-and-oil separator with the built-in pressure regulator 4, absorber receiver 3,
shown in Fig. I.11. Passing through the unit the air is purified from moisture and oil; then the air
is distributed to the circuits via four-circuit safety valve:
- the front axle circuit (the first circuit) consists of the air reservoir 8, the upper section of
the brake valve 20, the air hydraulic booster and the wheel cylinders of the front axle;
- the circuit of the left and of the right wheels of the bogie consists of the air reservoir 6,
the lower section of the brake valve 20, the air hydraulic boosters, the wheel cylinders of the left
and right side of the rear bogie;
1-plug; 2-inductive sensor; 3-locking bush; 4-
toothed impulse ring; 5-wheel hub
Fig. I.10 – Speed sensor
