METHOD FOR THE CONTACTLESS DETECTION OF THE POSITION OF A BUTTERFLY VALVE SHAFT OF A BUTTERFLY VALVE CONNECTING PIECE AND BUTTERFLY VALVE CONNECTING PIECE

摘要

The invention relates to a method for the contactless detection of the position of a butterfly-valve shaft of a butterfly valve connecting piece, the butterfly-valve shaft being driven by an electric actuator and having a magnet at one end, which is aligned in a contactless manner with a sensor that is located on a cover. An aim of the invention is to reliably guarantee the detection of the position of the butterfly-valve shaft, even over particularly long periods of time using a contactless position detection device. To achieve this, the sensor has a first and a second magnetoresistive sensor element, an approximately sinusoidal signal being generated in the first sensor element and an approximately cosinusodial signal being generated in the second sensor element by means of the magnet, during the rotation of the butterfly-valve shaft. According to the method, an approximately arc tangential signal is generated in the butterfly-valve connecting signal. The control signal is fed to the actuator that is located in the butterfly-valve connecting piece, to adjust the position of the butterfly-valve shaft.