Blood culture instrument

The utility model relates to a blood culture instrument. The blood culture instrument comprises a fixed frame (13) installed on a base (12), a swing frame (8) hinged in the fixed frame (13), as well as a motor (4) and a speed reducer (5) which are fixedly installed on the base (12), wherein the swing frame (8) is of a hollow rectangular structure, the swing frame (8) is installed in the fixed frame (13) in a swinging manner and hinged with a first connection rod (6) hinged on the speed reducer (5) by a second connection rod (7) on the swing frame (8). An optical detection sensor is installed on the swing frame (8) and swings with the swinging of the swing frame (8), thus avoiding the phenomenon of inaccurate detection brought by inaccurate motor displacement and detection hole position difference; moreover, each detection device is independent, and the position does not need to be found by the motor, thus saving the time needed for the displacement of the motor and increasing the detection speed.