Adjusting device for a flow controller

An adjusting device for adjusting a flow rate of a medical fluid conveying system, said adjusting device comprising a selection wheel for selecting one of a plurality of flow rates, an adjusting disk connected to the selection wheel and provided for adjusting the flow rate, and a detent comprising a pointed tip in engagement with an outer edge of the adjusting disk,

• wherein said adjusting disk has a star shape comprising a plurality of peaks and valleys along the outer edge of the adjusting disk, each valley comprising a point of minimum radius, and
• wherein the adjusting disk is rotatable between a plurality of stable positions, in which the pointed tip engages the outer edge of the adjusting disk at a point of minimum radius in one of the valleys, and a plurality of unstable positions, in which the pointed tip presses obliquely against the outer edge of the adjusting disk to urge the adjusting disk to one of the plurality of stable positions, so as to prevent the adjusting disk from remaining in an intermediate position between adjacent valleys,
• wherein the detent defines a first detent edge and a second detent edge that intersects the first detent edge at the pointed tip, the first detent edge separated from the second detent edge by a first angle,
• wherein each valley defines a first valley edge and a second valley edge that intersects the first valley edge at one of the points of minimum radius, the first valley edge separated from the second valley edge by a second angle, and
• wherein the first angle of the pointed tip is smaller than the second angle of each valley such that the pointed tip directly contacts each and every point of minimum radius when the adjusting disk is rotated.