Automatic weighing device

The invention discloses an automatic weighing device, comprising a weighting body, wherein a square gap is arranged on an edge of the weighting body, a first slide block and a second slide block are respectively arranged on two adjacent cross sections of the gap, the first slide block driven by a first cylinder makes translational motion relative to a weighing platform, the second slide block driven by a second cylinder makes translational motion relative to the weighing platform; a electronic display screen for weighting material; and a PLC controller, wherein a threshold is preset in the PLC controller, when the weight of a packaging bag is in a range of the threshold, the first slide block pulling the packaging bag out of the gap, and when the weight of a packaging bag is out of a range of the threshold, the second slide block pulling the packaging bag out of the gap. The automatic weighing device, by the preset threshold, can automatically judge whether the material to be measured is qualified or not, whi