Towing -680640051

TM 5-2420-224-20-1

AIR SYSTEM (CONT)

Towing

The valve (16.1) enables fast entry and escape of

air in the trailer brake system and maintains the

The vehicle is equipped with a brake system which

control pressure in the case of leakage in the

permits compressed air supply from the towing

trailer brake line.

vehicle, i.e., the system can be pressurized with

supply air and braked from a towing vehicle,

When the safety valve (33.2a) is actuated, supply

making it possible to maintain almost the same

air also flows to the changeover valve (33.1) on

operating conditions as in the case of an intact

the brake booster.

vehicle.

This valve has the task of disconnecting the outer

In this case, supply air flows via the front

chamber of the brake booster (27.7) as already

connection (35.0) to the large air tank; in this way,

described.

the auxiliary loads are also supplied.

The reduction of the power assistance causes an

Control air flows to the brake valve (A) via the

improvement in braking characteristics during

coupling head (35.1). The shuttle valve (28.3) is

trailer operation.

reversed by connection (2). In this way, the brake

booster (27.7) is actuated via connection (4), i.e.,

The antijackknife brake valve (15.1) is an

only the outer booster chamber is effective.

additional service brake valve which only acts on

the trailer. Its function can be graduated and is

used particularly for braking the trailer on slight

inclines, with the service brake in the tractor unit

not being used along side this brake.

The parking brake in the tractor vehicle acts

mechanically on the rear wheels and has no effect

on the trailer.

When a vehicle with trailer is parked, both the

vehicle and the trailer must be braked by means of

its own parking brake.

Change 1

1-16.7