Infusion device

The utility model discloses an infusion device which comprises a spring bin. Multiple lower tubes are arranged in the spring bin, multiple compressed springs are arranged in each lower tube, in the multiple compressed springs, the lengths of the large-diameter compressed springs are smaller than those of the small-diameter compressed springs, an upper tube is arranged on the spring bin, a piston is disposed in the upper tube, limiting clamps are arranged above the compressed springs of the lower tubes, the piston is upwards connected with a supporting element, the supporting element is provided with a light material bearing pad in a bearing mode, and a pressure upper cover is hinged to the spring bin. According to the infusion device, an external power supply is not needed, pressure output is achieved by means of a spring transmission device of the infusion device, and different pressures are transmitted to the pressure upper cover by weighing infusion bags with different weights to guarantee constant pressur