The pressure regulator automatically maintains the pressure in the pneumatic brake drive system within 620 ... 750 kPa, protects the pneumatic system from exceeding the limit pressure (1000 ... 1350 kPa) and protects the pneumatic system from contamination.
Pressure regulator: a device, b position when the pressure in the system is less than 700 ... 750 kPa, to the position when the regulator valve is activated (pressure in the system is 700 ... outputs, III output to the pneumatic system; I unloader valve, 2 filter, 3 plug of the air sampling channel, 4 exhaust valve, 5 balancing spring, 6 follower piston, 7, 8, II channels, 9 check valve, 10 inlet; valve, 12 relief piston
When the pressure in the system is less than 700 ... 750 kPa, compressed air from the compressor through the input I of the regulator, filter 2, channel 11 is supplied to the annular channel 8 and then through the check valve 9 and output III to the receivers of the vehicle's pneumatic system.
At the same time, through channel 7, compressed air passes into cavity A under piston 6, which is loaded with a balancing spring 5.
At the same time, the outlet valve 4, which connects cavity B above the unloading piston 12 with the atmosphere through outlet 11, is open, and the inlet valve 10, through which compressed air is supplied to cavity B, is closed under the action of a spring.
The unloading valve 1 is also closed by the action of the spring in the piston 12. Piston 12 is held in the top position.
After reaching a pressure of 700 ... 750 kPa in cavity A, the piston 6, having overcome the force of the balancing spring 5, moves upward. In this case, the outlet valve 4 closes, the inlet valve 10 opens and compressed air from cavity A enters cavity B.
The unloader valve 1 opens, allowing compressed air from the compressor through outlet IV to the atmosphere along with the condensate accumulated in the cavity. As a result, the pressure in channel 8 drops and the check valve 9 closes.
The compressor in this case runs unloaded without back pressure.
When the pressure drops to 620 ... 650 kPa in outlet III, piston 6 moves down under the action of spring 5, valve 10 closes, and exhaust valve 4 opens, communicating cavity B with the atmosphere through outlet II.
In this case, the unloading piston 12, under the action of the valve spring 1, occupies the upper position, the valve I is pressed against the seat, separating the input I from the atmosphere, and the compressor again pumps compressed air into the pneumatic system.
If the regulator does not work at a pressure of 700 ... 750 kPa, then the unloading valve 1, upon reaching a pressure of 1000 ... 1350 kPa in the pneumatic system, opens, overcoming the resistance of the springs. In this case, output I communicates with the atmosphere, preventing the pressure from rising above the specified value.
To connect special devices, the pressure regulator has an outlet closed with a screw plug 3.
In addition, there is an air bleed valve for tire inflation, which is closed with a cap.
When screwing on the fitting of the tire inflation hose, the valve is recessed, opening the entrance to the brake system.
Before inflating the tires, the pressure in the receivers should be reduced to the pressure corresponding to the inclusion of the regulator, since air must not be taken during idling.