| 摘要 |
A dual circuit trailer control valve for pressure medium operated tractor vehicle brake systems has two control pistons (22, 23), connected in series, for the operation of a combined inlet/outlet valve (28), which is arranged between an inlet chamber (11) and an outlet chamber (13) connected to a trailer brake line. The control pistons (22, 23) are each acted upon by one service brake circuit of the brake system respectively. A further control piston (25) is acted upon by a parking brake circuit of the brake system and, when the parking brake is applied, operates the combined inlet/outlet valve (28) in such a way that a brake control pressure is generated in the outlet chamber (13). For forced movement of the first control piston (22), which, in itself, remains motionless when the service brake is intact, a compression spring (53) is arranged between the said piston and the valve housing (10), which holds the control piston (22) in an initial position. The service brake pressure generated in the outlet chamber (13) by operation of the parking brake displaces the first control piston (22) against the force of the compression spring (53). <IMAGE>
|
