Bendix Commercial Vehicle Systems E-10 DUAL BRAKE VALVES 6/10 - Manual (Page 2)

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delivery ports – the primary piston will mechanically move
the relay piston, allowing the piston to close the secondary
exhaust valve and open the secondary inlet valve, allowing
air to
fl ow out the secondary delivery port.
BALANCED: PRIMARY CIRCUIT
When the primary delivery pressure acting on the piston
equals the mechanical force of the brake pedal application,
the primary piston will move and the primary inlet valve will
close, stopping further
fl ow of air from the primary supply
line through the valve. The exhaust valve remains closed,
preventing any escape of air through the exhaust port.
BALANCED: SECONDARY CIRCUIT
When the air pressure on the secondary side of the relay
piston approaches that being delivered on the primary
side of the relay piston, the relay piston moves, closing the
secondary inlet valve and stopping further
fl ow of air from
the supply line through the valve. The exhaust remains
closed as the secondary delivery pressure balances the
primary delivery pressure.
When applications in the graduating range are made, a
balanced position in the primary circuit is reached as the air
pressure on the delivery side of the primary piston equals
FIGURE 3 - BENDIX ® E-6 ® DUAL BRAKE VALVE
SECTIONAL DIAGRAM
14 30
32
31
33
28
15
9 11 10
25
16
12
13
20
21
24
23
22
27
26
17
19
18
7
8
18
4
5
19
1
2
6
16
17
APPLYING: NORMAL OPERATION -
SECONDARY CIRCUIT
When the primary inlet valve is moved off its seat, air is
permitted to pass through the bleed passage and enters the
relay piston cavity. The air pressure moves the relay piston,
which contains the exhaust seat, and closes the secondary
exhaust valve. As the secondary exhaust valve closes, the
secondary inlet valve is moved off its seat allowing the
secondary air to
fl ow out the secondary delivery port.
Because of the small volume of air required to move the
relay piston, action of the secondary circuit of the valve is
almost simultaneous with the primary circuit portion.
APPLYING: LOSS OF AIR IN THE SECONDARY
CIRCUIT
Should air be lost in the secondary circuit, the primary
circuit will continue to function as described above under
Normal Operation: Primary Circuit Portion.
APPLYING: LOSS OF AIR IN THE PRIMARY
CIRCUIT
Should air be lost in the primary circuit, the function will
be as follows: as the brake treadle is depressed – and no
air pressure is present in the primary circuit supply and
FIGURE 4 - BENDIX ® E-10 ™ DUAL BRAKE VALVE
SECTIONAL DIAGRAM
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