Zwei Ventilanordnungen zur Aufrechterhaltung eines konstanten Druckbereiches in einem Drucksystem

摘要

The invention provides a valve arrangement with a pressure control valve placed on a pressure line extending between a source of fluid under pressure and a pressure system in which a constant pressure is to be maintained. The pressure control valve is able to be operated in response to a pressure sensor which is preferably in the form of a venturi element. This pressure sensor is arranged in the pressure line is placed downstream from the pressure control valve and is connected with at least one control port of a pressure switching valve arrangement subject to switching hysteresis, for the pressure control valve. The pressure control valve arrangement is operated by the pressue measured at the position of the pressure sensor. In order to amplify this signal there is the downstream pressure control valve. Owing to overlapfree switch made possible by the hysteresis long venting cycles are prevented and the number of switching operations reduced.