Description:
As the name suggests, the four-circuit protection valve has the job of protecting the individual circuits from each other. They're used to supply the independent circuits with compressed air. In the event of any circuit failing, that circuit is switched off automatically, the others continuing to be supplied with compressed air up to the opening pressures in the defective circuit. It should be prevented that, when in one system there is a pressure loss, other systems are also strongly impaired. The quadruple-circuit protection valves are used with circuits (1) and (2) for dual-circuit braking system, and with circuits (3) and (4) for ancillary consumers.
Working Principle
Connection 1 is the air inlet (connected directly with air dryer via 21), and 21, 22, 23, 24 are air outlets (each outlet is a circuit).
On the basis of the different applications, four circuits have different air inflow ways. Parallel arrangement, all circuits are connected with each other and this means that a limited return flow from the ancillary consumers to primary consumers is possible. Series arrangement, this means that ancillary consumers (circuits 3 and 4) follow the primary consumers (circuits 1 and 2 ). No return flow is possible from the ancillary consumers to the primary consumers.
The compressed air flows into the four-circuit protection valve by way of the compressor, the air dryer and the pressure control valve through the connection 1 and into the four circuits through the bypass-valve (a, b, c, d) and the check valve (h, j, q, r). Meanwhile, valves (g, k, p, s) openonly after a certain pressure (protective pressure)has been reached and diaphragms (f, i, o, t) summon up against the force of springs(e, m, n, u). And then the compressed air fills air reservoirs (1) & (2) of the braking system via 21 & 22 and fills circuits 3 and 4 via 23 & 24. The circuit 3 supplies air to truck's emergency brake and parking brake systems as well as to the trailer. The circuit 4 supplies air to the auxiliary braking system.
E. G. Ifcircuit (21) fails, valve (s) is closed by the force of spring (u). This will initially cause the pressure in circuit (22) to fall below the opening pressure. At this point, it is not possible for circuits (23) and (24) to be affected since the check valves (q) and (j) close immediately. Due to the fall in pressure in circuit (21), the compressor will once again switch to delivery, continuing to feed the intact circuit (22) up to the opening pressure of circuit (21). If the pressure at port (1) exceeds the opening pressure of valve (s), the higher pressure will escape at the defective point of circuit (21). This ensures that the intact circuit (22) continues to receive compressed air.
|
OEM |
HYozma No. |
|
934 714 1090 |
934 714 1090 |
|
934 702 2100 |
934 702 2100 |
|
934 702 2210 |
934 702 2210 |
|
934 702 2500 |
934 702 2500 |
|
934 702 2600 |
934 702 2600 |
|
934 702 3000 |
934 702 3000 |
|
934 714 1100 |
934 714 1100 |
