DIFFERENTIAL PRESSURE VALVE FOR CONTROLLING A SYSTEM HAVING A HEAT CARRYING MEDIUM

摘要

PCT No. PCT/DK94/00465 Sec. 371 Date Jun. 7, 1996 Sec. 102(e) Date Jun. 7, 1996 PCT Filed Dec. 13, 1994 PCT Pub. No. WO95/17622 PCT Pub. Date Jun. 29, 1995The invention relates to a differential pressure valve for the control of a plant with a heat carrying medium. The differential pressure valve has a membrane controlled by a differential pressure for the regulation of the flow of the heat carrying medium between an inlet and an outlet, an adjustable closing member between the inlet and the membrane, one or more fixed openings, the areas of which can be changed linearly by the closing member, one or more variable openings, the areas of which are changed by the membrane, and electrically activated members for closing one of the variable openings or fixed openings by force or by time control independently of the flow in the valve. The invention is configured as parts to be inserted in a known differential pressure valve without dismounting it in such a plant. It is the object of the invention in very small steps to control the flow in the whole plant, in a single part thereof or in several sections of a cooling or heating plant, each section being divided into zones.