BENDIX R-12P PILOT RELAY VALVE Handbuch - Seite 4
Blättern Sie online oder laden Sie pdf Handbuch für Kontrolleinheit BENDIX R-12P PILOT RELAY VALVE herunter. BENDIX R-12P PILOT RELAY VALVE 8 Seiten. Pilot relay valve
LOAD PISTON
RELAY PISTON
SUPPLY PORT
INLET/EXHAUST
VALVE
FIGURE 6 - RAPID EXHAUST
RAPID EXHAUST
Figure 6 shows a rapid service brake release. Air above
the relay piston travels back out the control port to be
exhausted. With the lack of air pressure above the
piston, air pressure below lifts the piston, closing the inlet
and opening the exhaust. Delivery air then exhausts to
atmosphere.
EQUALIZING (SLOW) APPLICATION
When a control signal enters the R-12P
on the relay piston. However, Figure 7 shows the control
signal passing through the valve without causing piston
movement. The air is passing through the relay piston's
equalizing orifi ce, directly through the valve and out the
delivery port to the next valve in the air system. This
situation occurs if air pressure build-up is slow and the
pressure above the relay piston is not strong enough to
open the valve. (Air pressure above the piston must be at
least 3 psi greater than air pressure below the piston to
cause movement.)
In the equalizing application, even though the inlet valve
does not open, the control signal is not decreased because
the equalizing orifi ce allows it to pass directly through the
™
R-12P
valve. Note that this condition exists during very
slow service brake applications.
4
CONTROL PORT
DELIVERY PORT
EXHAUST
FIGURE 7 - EQUALIZING (SLOW) APPLICATION
For example, if a vehicle is traveling over a long downhill
grade, the driver may want to limit speed and maintain
vehicle control through proper gearing, engine speed and
a light service brake application.
™
valve, it acts
FIGURE 8 - EQUALIZING (SLOW) EXHAUST
LOAD PISTON
RELAY PISTON
SUPPLY PORT
INLET/EXHAUST
VALVE
LOAD PISTON
RELAY PISTON
SUPPLY PORT
INLET/EXHAUST
VALVE
CONTROL PORT
DELIVERY PORT
CONTROL PORT
DELIVERY PORT