URAL Motorcycles URAL-4320-60, Руководство по эксплуатации

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When the service brakes are applied the parking brake system is blocked.
When there is no pressure in the outlet I the piston 3 is in the upper position. The inlet
valve 5 is closed under the action of spring; the outlet valve 4 is opened.
Through the opened outlet valve and outlet II the spring brakes are connected to the at-
mosphere via outlet III. The truck is braked by spring brakes. If the truck is braked by service
brakes system in so doing, then the pressure from the brake valve goes into outlet V and moves
the piston 2 down together with the piston 3. Outlet valve 4 is closed and inlet valve 5 is opened.
So the service brake is protected against the joint effort of service brake diaphragm and spring
brake.
1-upper body; 2-upper piston; 3-lower piston; 4-outlet valve; 5-inlet valve; 6-valve’s body; I-outlet from
the hand operated brake valve; II-outlet from spring brakes; III-outlet to the atmosphere; IV-outlet from air
reservoir; V-outlet from the brake valve
Figure 95 – Parking Brakes Acceleration Valve
5.5.5.4 Return valve is shown in Fig. 96. When the compressed air is delivered into the
outlet I, the valve 2 is opened having overcome the spring 3 effort; due to that the compressed air
goes to the outlet II. When the pressure in the outlet I is reduced, the valve 2 goes to the seat in the
body 1 due to spring 3 effort and pressure difference in the outlets I and II. Reverse flow of the
compressed air from the outlet II to the outlet I is impossible.
1-body; 2-valve; 3-spring; 4- guide bushing; 5-thrust
ring; I-compressed air inlet; II-compressed air outlet
Figure 96 – Return Valve