Abstract: A valve having a closure member which is pressed against a valve seat in a closed position and closes an opening, and having a first valve drive for moving the closure member along a first movement path back and/or forth between a maximum open position and an intermediate position, and having a second valve drive for moving the closure member along a second movement path back and/or forth between the intermediate position and the closed position. The first movement path and the second movement path are arranged in an angled manner with respect to one another. The valve additionally includes at least one locking device with at least one locking body which interacts with at least one inclined surface and/or comprises at least one inclined surface, wherein the locking body is movable relative to the closure member along a third movement path between a locking position and a releasing position.

Abstract: A valve having a closure member which is pressed against a valve seat in a closed position and closes an opening, and having a first valve drive for moving the closure member along a first movement path back and/or forth between a maximum open position and an intermediate position, and having a second valve drive for moving the closure member along a second movement path back and/or forth between the intermediate position and the closed position. The first movement path and the second movement path are arranged in an angled manner with respect to one another. The valve additionally includes at least one locking device with at least one locking body which interacts with at least one inclined surface and/or comprises at least one inclined surface, wherein the locking body is movable relative to the closure member along a third movement path between a locking position and a releasing position.

Abstract: The invention relates to a retroreflector or a retroreflector arrangement in which the faces of the retroreflector are directly heated by a heating element. The retroreflector comprises a triple-mirror prism having three isosceles limiting faces and one equilateral limiting face. Also, the retroreflector has at least one heating element in direct contact with each of the faces. The heating elements directly heat the faces. As a result, the effectiveness of the retroreflector is not diminished in extreme weather conditions, for instance, in extremely cold or humid conditions.