BENDIX SD-13-4793 ユーザーズマニュアル
1
SD-13-4793
DESCRIPTION
There are two Bendix antilock modulators available from
Bendix Commercial Vehicle Systems LLC, the older M-21
Bendix Commercial Vehicle Systems LLC, the older M-21
™
modulator and the newer M-22
™
modulator. Both are
functionally the same.
The M-21
™
and M-22
™
antilock system modulators (Figure
1) are essentially high capacity, on/off air valves that
incorporate a pair of electrical solenoids for control. The
solenoids provide the electro-pneumatic interface or link
between the antilock controller electronics and the air brake
system. The modulator can be used to control the braking
function on an individual wheel or two service actuators.
When used to control both service chambers on an axle
or two chambers on the same side of a tandem axle, the
modulator is sometimes mounted ahead of a quick release
incorporate a pair of electrical solenoids for control. The
solenoids provide the electro-pneumatic interface or link
between the antilock controller electronics and the air brake
system. The modulator can be used to control the braking
function on an individual wheel or two service actuators.
When used to control both service chambers on an axle
or two chambers on the same side of a tandem axle, the
modulator is sometimes mounted ahead of a quick release
valve, which provides quick exhaust of service applications
during normal braking. (Figure 2) In the case of individual
wheel control applications, the modulator is always the
last control valve through which air passes on its way
to the service brake actuator and a solenoid assembly
which contains one normally open solenoid (NOS), one
normally closed solenoid (NCS), and two inlet and exhaust
diaphragm valves. A Packard, three pin, 280 series weather
resistant electrical connector is an integral part of the
modulator solenoid assembly and serves to carry control
commands from the antilock controller to the modulator.
Two, .35 inch diameter, mounting holes are provided for
frame or cross member mounting. The single supply,
delivery and exhaust port on both modulators is identifi ed
with a cast, embossed numeral for positive identifi cation.
during normal braking. (Figure 2) In the case of individual
wheel control applications, the modulator is always the
last control valve through which air passes on its way
to the service brake actuator and a solenoid assembly
which contains one normally open solenoid (NOS), one
normally closed solenoid (NCS), and two inlet and exhaust
diaphragm valves. A Packard, three pin, 280 series weather
resistant electrical connector is an integral part of the
modulator solenoid assembly and serves to carry control
commands from the antilock controller to the modulator.
Two, .35 inch diameter, mounting holes are provided for
frame or cross member mounting. The single supply,
delivery and exhaust port on both modulators is identifi ed
with a cast, embossed numeral for positive identifi cation.
Bendix
®
M-21
™
and M-22
™
AntiLock Modulator Assembly
FIGURE 1 - M-21
™
AND M-22
™
MODULATOR
M-21
™
MODULATOR
M-22
™
MODULATOR
SUPPLY
(CAST-IN ID #1)
SUPPLY
(CAST-IN ID #1)
DELIVERY
SUPPLY
MOUNTING
HOLES
DELIVERY
(CAST-IN ID #2)
SOLENOID
CONNECTOR
SUPPLY
DELIVERY
EXHAUST
(CAST-IN ID #3)
SOLENOID
CONNECTOR
MOUNTING
HOLES
DELIVERY
(CAST-IN ID #2)
EXHAUST
(CAST-IN ID #3)