BENDIX SD-03-812 Manuel D’Utilisation

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 SD-03-812
DESCRIPTION
The Bendix
®
 E-2
 and E-3
 brake valves are single circuit brake valves 
that provide the driver with single point control of the service braking 
system. The valve can be either treadle operated or fi tted with a lever 
for a linkage connection to a conventional brake pedal. Movement of 
the treadle or pedal controls the graduated application and release of 
air pressure to the vehicle brake actuators, applying or releasing the 
vehicle brakes.
The E-2
 and E-3
 brake valves utilize a rubber spring confi ned in a 
retainer, resulting in reduced plunger travel as compared to previous 
design single circuit brake valves.
The E-3
 brake valve differs from the E-2
 valve in that it employs 
a different piston (see insert Fig. 1), which requires greater plunger 
travel. Because of the greater plunger travel, the E-3
 valve provides 
less sensitivity in the 0-40 psi application range as compared to the 
E-2
 valve. Other than the different pistons, the E-2
 and E-3
 valves 
are identical. An identifi cation washer, located under the retaining ring 
in the valve’s exhaust port, provides a means of identifying the E-2
 
and E-3
 brake valve.
The E-2
 and E-3
 valves have an insert type inlet/exhaust valve 
assembly which can be removed without disconnecting air lines. An 
exhaust check valve in the bottom of the insert prevents contaminants 
from entering the valve through the exhaust port. An optional exhaust 
extension is available should an exhaust carry-off line be required.
Porting consists of two (2) 1/2 inch P.T. supply ports, four (4) 3/8 inch 
or 1/2 inch P.T. delivery ports, and two (2) 1/4 inch P.T. accessory ports 
(in the supply portion of the valve).
OPERATION
Applying
Applying the treadle or pedal exerts a force on the plunger, rubber 
graduating spring and piston. The downward movement of the piston 
causes the piston stem (which is the exhaust seat) to contact the valve, 
closing the exhaust. As the exhaust closes, the inlet valve moves away 
from its seat. Air pressure is then allowed to fl ow by the inlet valve, out 
the delivery ports and to the brake actuators, applying the brakes.
Bendix
®
 E-2
 & E-3
 Brake Valves
FIGURE 1 - 
E-3
 BRAKE VALVE (SECTIONAL VIEW)
RETAINER
O-RING
PISTON 
RETURN 
SPRING
RETAINING
RING
PRELOAD
SPRING
EXHAUST CH.
VALVE SEAT
INLET/EXHAUST 
VALVE
CAP SCREW
INSERT ASS’Y
SPRING SEAT
WASHER
RUBBER SPRING
RETAINER
VALVE SPRING
O-RING
O-RING
DIAPHRAGM
WASHER
SCREW
11
10
6
2
3
1
4
12
8
9
21
20
19
18
17
16
15
14
13
MOUNTING 
PLATE
TREADLE
AUXILIARY
PORTS (2)
DELIVERY
PORTS (4)
EXHAUST
SUPPLY
PORTS (2)
7
PISTON
E-2
 - E-3
 BRAKE VALVE
AUXILIARY
PORTS (2)
DELIVERY
PORTS (4)
EXHAUST
SUPPLY
PORTS (2)