PRESSURE CONTROL DEVICE FOR A TIRE INFLATING SYSTEM WITH A ROTARY FEEDTHROUGH, AND TIRE PRESSURE CHANGING METHOD

摘要

The invention relates to a pressure control device (28) for a tire inflating system (30) of a motor vehicle, said device receiving (134) compressed air via a ventilating inlet (32), activating (142) at least one seal for sealing an air chamber (98) between a stator (90) and a rotor (92) of a rotary feedthrough (14) via a seal actuating outlet (36), and ventilating a tire (12) of the motor vehicle at a ventilating outlet pressure via a ventilating outlet (34) and via the rotary feedthrough (14). The pressure control device (28) has a control valve (38) that can be controlled pneumatically by means of a control pressure, the ventilating outlet (34) being ventilated (156) at the ventilating outlet pressure by means of the control valve only when the control pressure is at least as high as a defined minimum control pressure (158). The pressure control device (28) further has a compressed air duct such that in response to a pressure build-up (136) at the previously ventilated ventilating inlet (32) at least up to the minimum control pressure, the control pressure and the seal actuating pressure are built up (148, 140) for ventilating purposes (156), but the control pressure is built up (148) to said minimum control pressure in a delayed manner with respect to the build-up of the seal actuating pressure to the minimum control pressure. In this manner, an activation (142) of a seal (100, 100') prior to the ventilation (156) of the ventilating outlet (34) is possible without additional actuating channels. The invention further relates to a rotary feedthrough (14), a tire inflating system (30), a motor vehicle, and a tire pressure changing method (128).