Abstract: The invention relates to a fluid delivery device (2, 2?) for delivering a fluid into a human or animal body. The fluid delivery device (2, 2?) comprises a fluid chamber (4, 4?) for receiving a fluid, an oscillator (6, 6?) for imparting oscillations to at least a portion of the fluid and a control for controlling the oscillator (6, 6?). The oscillator (6, 6?) comprises a vibrator (8, 8?) and a resonator (10, 10?). The resonator (10, 10?) has a main body (12, 12?), defining an interior volume (14, 14?), and a neck (16, 16?). The neck (16, 16?) is connected to the main body (12, 12?) and in fluid communication with the interior volume (14, 14?). The vibrator (8, 8?) is configured to impart vibrations to the resonator (10, 10?). The control is configured to control operation of the vibrator (8, 8?) so as to impart vibrations to the resonator (10, 10?) at a resonance frequency of the resonator (10, 10?) or at a frequency which is within ±20% of a resonance frequency of the resonator (10, 10?).

Abstract: An inhalation system comprising an inhalation device and a flowmeter (12) that comprises a flow chamber (15), a resistor body (20) and a flow indicator (21), wherein said flow chamber (15) comprises an inlet opening (17) that can be connected to the surroundings, an outlet opening (18) that can be connected to an interior of the inhalation device, and a flow resistance device, said inhalation system being configured to guide supply air through the inlet opening (17) into the flow chamber (15), through the outlet opening (18) out of the flow chamber (15) and into the interior of the inhalation device, said resistor body (20) being configured to be able to assume different positions in the flow chamber (15), and said flow indicator (21) being configured to indicate a position of the resistor body (20) in the flow chamber (15).