BENDIX SR-7 SPRING BRK MODULATING VALVE Приложения - Страница 6
Просмотреть онлайн или скачать pdf Приложения для Блок управления BENDIX SR-7 SPRING BRK MODULATING VALVE. BENDIX SR-7 SPRING BRK MODULATING VALVE 9 страниц. Spring brake modulating valve
CONTROL LINE PRESSURE
SECONDARY RESERVOIR
CONSTANT PRESSURE
FIGURE 9 - SERVICE APPLICATION LOSS OF PRIMARY CIRCUIT
SERVICE APPLICATION WITH LOSS OF AIR IN
PRIMARY CIRCUIT (FIGURE 9)
With the parking brakes released (dash valve button in) and
the absence of air in the primary circuit delivery, a service
brake application from the secondary circuit causes the
pressure in the spring brakes to be exhausted proportionally
to this application. This is known as spring brake modulation.
A 30 psi service brake application will exhaust the spring
brake pressure to approximately 60 psi.
CONTROL LINE PRESSURE
IN-LINE SINGLE
CHECK VALVE
SECONDARY RESERVOIR
NO PRESSURE
FIGURE 10 - SERVICE APPLICATION LOSS OF SECONDARY CIRCUIT
6
MAIN PISTON MOVES UP
à
à
INLET VALVE SEATED
à
à
BALANCE PORT - LOSS OF
PRIMARY CIRCUIT PRESSURE
CONTROL PORT - SECONDARY
à
CIRCUIT PRESSURE
AIR EXHAUSTS FROM
à
SPRING BRAKES
SERVICE APPLICATION WITH LOSS OF AIR IN
SECONDARY CIRCUIT (FIGURE 10)
With the parking brakes released (dash valve button in) and
the absence of air in the secondary circuit reservoir, the
external single check valve in the supply port seals to prevent
air leakage to atmosphere from the SR-7
valve delivery air flows through the in-line single check valve
™
and becomes SR-7
valve supply air. This air is delivered to
maintain at least 107 psi (nominal) in the spring brake
chambers.
BALANCE PORT - PRIMARY
à
CIRCUIT PRESSURE
CONTROL PORT - LOSS OF
SECONDARY CIRCUIT PRESSURE
à
DELIVERY TO
SPRING BRAKES
™
valve. The dash