Abstract: The present invention relates to a detection arrangement, comprising: an actuation element, which is designed to be moved back and forth between at least one first and one second position; a fastening portion, which is designed such that the actuation element can be brought into contact with a tube; a spring element, which interacts with the actuation element such that the spring element exerts a force on the actuation element in the direction of the second position; a retaining element, which interacts with the actuation element such that the actuation element can be moved into the first position by means of the retaining element; and a control element, which is designed to detect at least one parameter of the actuation element and/or of the retaining element and evaluate same so that the control element, on the basis of this evaluation, provides information about the condition of the detection arrangement.

Abstract: The present invention relates to a pump, comprising a pump actuator (2) having at least one electroactive polymer, as well as at least one return element (8, 9) which returns a displacement element (5) of the pump after a pump stroke to a defined position. The invention further relates to a metering unit and to a medical apparatus comprising such a pump.

Abstract: The invention relates to a respiratory air purifier device.