Pipettiervorrichtung und Verfahren zur Detektion der Aufnahme von Spitzen

It is known to use proboscises in clinical analyzers to aspirate and dispense liquid at a dispensing station. These proboscises need positional control to prevent vertical overtravel when picking up disposable tips prior to the aspirating and dispensing steps. This is normally achieved using a sensor arrangement which needs to be re-calibrated every time a part of the proboscis is replaced or there is a variation in the distance over which the proboscis needs to travel for tip pickup. Described herein is a proboscis and method of use which automatically detects whether or not a disposable tip (130) has been properly picked up. The proboscis features a probe (110) supported on a base (150) movable within a driven housing (112), a sensing flag (114) with multiple signalling stations (160, 160') being fixed to the base (150). These allow the sensor (116, 162) cooperating with the flag (114) to be fixed to the frame (122) of an analyzer using this proboscis, rather than to be adjustably attached, so that no adjustment is required for re-calibration to account for any change in position of the sensor (116, 162).