Abstract: A gas supply control device includes a main body, a control valve assembly extending into and received in the main body, a bottom lid attached to a bottom surface of the main body, and a top cover attached to a top surface of the main body. The gas supply control device provides an effect of simplicity and accuracy of gas supply therethrough.

Abstract: The invention relates to a double valve with a valve housing (1), for housing two double-headed actuators (30, 31), whereby the double head actuators have differing head diameters (12, 13) and the flow of a fluid through the both actuators (30, 31) in the valve housing (1) is identical. The valve housing (1) is of one-piece design and a drive function for both actuators (30, 31) is not connected to the inner volume of the valve housing (1) with fluid flowing therein.

Abstract: The invention describes a shut-off valve having a double seat with an upper valve seat (7) of a diameter D1 and a lower valve seat (8) of a diameter D2 different to the diameter D1 (D1<D2), and a double-head setting member (12, 11, 10, 14) which in the closed condition prevents passage therethrough of a medium which is to be sealed off. The annular surface (D2−D1) of the double-head setting member (12, 11, 10, 14), which is acted upon by the medium to be sealed off and affords a closing force, and is formed from the outside diameter D2 and the inside diameter D1, is divided by a diameter D3 (D1<D3<D2) into at least two regions (10, 14) in order to distribute the closing force to the upper valve seat (7) and the lower valve seat (8).