gf4220b300101b

Parking brake valve, function

Tipo gf · tema 42.20 · versione 0100 · 2016-02-12

Valido per:

Non disponibile in “it”; mostrato in Inglese.

Collocazione

Gruppo funzionale 2 Telaio › 42 Freni impianto idraulico e meccanico › 42.20 Freno di stazionamento — Serie 384 · Serie 386 · Serie 388 (modelli 019, 024, 025, 364, 366) · Serie 682 (modelli 003, 027, 122, 123, 128, 133, 181, 186, 191, 3**)

EinPAS 21 Freni/impianto di depressione/impianto pneumatico › 21.16 Freno di stazionamento › 21.16.13 Tubazione/flessibile/valvola — Serie 384 · Serie 386 · Serie 388 (modelli 019, 024, 025, 364, 366) · Serie 682 (modelli 003, 027, 122, 123, 128, 133, 181, 186, 191, 3**)

GF42.20-B-3001-01B

Parking brake valve, function

Parking brake valve, function

B42.60-0274-03

Framework

1 Lever (handle)

2 Inlet valve

3 Discharge (exhaust)

4 Outlet valve

5 Valve body

6 Piston

a Inlet chamber

b Outlet chamber

11 Supply connection

21 Outlet connection with pressure to operate the parking brake through the relay valve

Operation

The parking brake application is done with the depressurization of the accumulator springs.

On the running position, the operating lever (1) is released. Chamber (a) is incommunication with chamber (b).

Gradually applying the lever (1), the communication between chambers is interrupted,the pressure in chamber (b) is progressively decreased as a consequence of the exit ofcompressed air from chamber (b) to the atmosphere through the discharge valve (4) and the dischargepipe (3).

Chamber (b) is connected through connector 21 to the relay valve (16.01) of the parkingbrake. In towing vehicles, besides the relay valve, it is also connected to the trailerdistributor valve (18.01).

This way, the parking brake valve allows: The use of the parking brake as auxiliary brake and the use of the parkingbrake in the trailer.

When the lever is applied to the running position until approximately 55th, it finds a higher resistance point that, when reached, allowsreaching the parking position and locking the lever.

The intake valve (2) is closed and the chamber (b) communicates with the atmosphere, the control pressure issued by the valve decreases,depressurizing the cylinders and allowing the expansion of the springs, which equals to the application of the parking brake.