Patent ID: 11867579
Assignee: EUROIMMUN MEDIZINISCHE LABORDIAGNOSTIKA AG
Field: Measurement (Instruments)
Classification: CPC B  G | IPC G

Claim 7:
8. A device for detecting an error state when aspirating a liquid, including
an aspiration needle (AW) having a tip (SP),
an activatable movement device (HT, G) for moving the aspiration needle (AW),
a pressure generating unit (P) for generating a negative pressure in the aspiration needle (AW),
a pressure sensor unit (S) for measuring a sensor signal (SG), which indicates a pressure in the aspiration needle (AN),
an activation and evaluation unit (C) having a first interface (K1) to the pressure generating unit (P), furthermore a second interface (K2) to the pressure sensor unit (S), and a third interface (K3) to the movement device (HT, G),
wherein the activation and evaluation unit (C) is furthermore designed
to activate the movement device (HT, G) in such a way that the tip (SP) of the aspiration needle (AW) is immersed in the liquid (PF),
to continuously acquire a sensor signal curve (SK) via continuous measurement of the sensor signal (SG) during an overall time period (TG), which comprises the predetermined time period (TD) and furthermore a further time period (TW) following the predetermined time period (TD),
to detect the error state in the case in which the sensor signal falls below a first threshold value during the predetermined time period (TD),
to provide a predetermined reference signal curve (RK),

wherein the activation and evaluation unit (C) is characterized in that it is furthermore designed
to determine a deviation measure (IN), which indicates a deviation of the sensor signal curve (SK) from the reference signal curve (RK) for the further time period,
to provide a predetermined second threshold value (SW2),
and to detect the error state in the case that the sensor signal fall below a first threshold value during the predetermined time period (TD) or detecting the error state after expiration of the further time period (TW) in the case that the deviation measure (IN) deviates sufficiently from the second threshold value (SW2).