Abstract: An electronically driven control valve, in particular for refrigeration, comprises a main pipe (2) with two end pieces (4, 6) which can be made into inlet and outlet and an elastic center piece (8) which can be loaded externally with pressure to change its shape and hence its flow cross-section. The main pipe is surrounded in the zone of the elastic center piece by a perforated support tube (10) which in turn is surrounded at a distance by an enclosing tube (12), whereby an impermeably sealed enclosing space (16) is formed between the center piece (8) and the enclosing tube (12). A filling medium (18) in the saturated state is present in that enclosing space. This filling medium can be heated by a heater element to generate a desired vapor pressure and to change the shape of the elastic center piece. The change in shape of the elastic center piece is sensed using an inductive or capacitive pickup (25). The measurement signals from the pickup are analyzed to drive the control valve.